Bioengineered Soft Microfibers Improve T-Cell Production

Columbia engineers bioengineer soft microfibers to improve T-cell production.

T cells play a key role in the body’s immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, chemical-based approaches. These “living drugs” are poised to transform medicine, with a growing number of cellular therapies receiving FDA-approval.

A current bottleneck in these approaches and other Adoptive T-cell Therapies (ACTs) is the production of sufficient numbers of high quality T cells. As a starting material, cells are isolated from the patient and then modified and grown outside the body in a bioreactor. This is still a new manufacturing challenge in medicine, and lack of a therapeutic number of cells is a frequent point of failure in ACT. In addition to technical challenges faced in consistent production of cells, T cells from patients undergoing treatment for cancer often show reduced function due to the disease, and are particularly difficult to grow.

A Columbia Engineering team has developed a new method for improving T-cell manufacture by focusing on the materials involved in this process. The team is a collaboration between Biomedical Engineering faculty Lance C. Kam and Helen H. Lu, whose research programs include immune engineering and smart biomaterial design. Their study, which is published today in Advanced Biosystems, uses a polymer mesh to activate the T cells, a critical step for their production. This approach simplifies processing compared to systems in use today. In addition, making the fibers out of a mechanically soft material improved T-cell growth, outperforming the current gold standard on several fronts.

“Our report shows that this soft mesh material increases the number of functional cells that can be produced in a single step,” Kam says. “In fact, our system provided nearly an order of magnitude more cells in a single process. What’s especially exciting is that we’ve been able to expand cells isolated from patients undergoing treatment for leukemia. These cells are often very difficult to activate and expand, and this has been a barrier to using cellular immunotherapy for the people who need it.”

In testing the effect of a softer material on T-cell production, the team was inspired by the field of mechanobiology. Researchers have known that other cell types can sense the mechanical stiffness of a material. For example, the rigidity of a material used to culture stem cells can direct differentiation, with a softer material promoting production of neuron while a stiffer substrate encourages bone cell differentiation. This effect can be as strong as the chemicals normally used to direct differentiation. However, a similar effect was unexpected in T cells for activation.

“This makes sense for cells normally involved in force-related activities, like muscle cells or fibroblasts that are involved in wound closure and healing. Our group was one of the first to explore this possibility for T cells, which are not associated with such functions,” Kam notes. These early experiments, involving his Microscale Biocomplexity Laboratory group, discovered that T-cells can sense the mechanical rigidity of the materials commonly used in the laboratory. To turn this into a clinically useful system, his group partnered with Lu’s Biomaterials and Interface Tissue Engineering Laboratory to create a microfiber-based platform.

Beyond simplifying the process of cell expansion and improving T-cells expansion, Kam and Lu envision that the mesh platform will have applications beyond immunotherapy. They are refining their platform and exploring how T cells from cancer patients respond to their materials. Says Lu, “It is truly exciting to see how these bioinspired matrices can direct cell function and be successfully used for T-cell therapy.”

Two New Breast Cancer Genes Emerge from Lynch Syndrome Gene Study

The findings suggest that genetic screening for breast cancer should be expanded to include MSH6 and PMS2

Researchers at Columbia University Irving Medical Center and NewYork-Presbyterian have identified two new breast cancer genes. Having one of the genes—MSH6 and PMS2—approximately doubles a woman’s risk of developing breast cancer by age 60.

The study, in collaboration with GeneDx, a genetic testing company, was published online today in Genetics in Medicine.

The two genes were previously known to cause Lynch syndrome, an inherited condition that raises the risk of colorectal, ovarian, stomach, and endometrial cancer. Lynch syndrome is the most common inherited cause of colorectal cancer, accounting for about 3 percent of newly diagnosed cases. One in 440 Americans has a gene variant that causes Lynch syndrome.

Researchers had suspected that Lynch syndrome genes may also cause breast cancer. Some studies had found a link, whereas others had not.

“People with Lynch syndrome aren’t thinking they may also be at risk for breast cancer,” said Wendy Chung, MD, PhD, the Kennedy Family professor of pediatrics (in medicine) at Columbia University Irving Medical Center, clinical geneticist at NewYork-Presbyterian/Columbia, and the study’s senior author. “Given the fact that genomic analysis is becoming more common in patients with a personal or family history of cancer, we have an opportunity to do more targeted breast cancer screening in women who carry any of the genes associated with risk for this disease.”

The researchers analyzed a database of more than 50,000 women who had undergone multi-gene hereditary cancer testing between 2013 and 2015. Of these, 423 women had a mutation in one of the four genes that cause Lynch syndrome: MLH1, MSH2, MSH6, and PMS2.

Additional analyses revealed that women with a mutation in two specific Lynch syndrome genes—MSH6 and PMS2—had a two-fold higher risk of breast cancer compared to women in the general population.

Based on the incidence of cancer in the study population, the researchers calculated that about 31 to 38 percent of women with cancer-causing MSH6 and PMS2 variants will develop breast cancer, compared to around 15 percent of women in the general population.

“The new study suggests MSH6 and PMS2 should be added to the list of genes to screen for when there is a history of breast cancer,” said Dr. Chung, who is also director of the clinical genetics program at NewYork-Presbyterian/Columbia. “Screening for these genes also would give these families potentially life-saving information to prevent colon cancer by encouraging individuals with the genes to increase the frequency of their colonoscopies.”

Currently, testing for Lynch syndrome genes is generally only done when someone has a personal or family history of colon or uterine cancer.

Dr. Chung added, “Given that Lynch syndrome is not rare in the general population, this finding has the potential to impact tens of thousands of people in the U.S. and could change standard practice related to one of the most common cancer predisposition syndromes.”

The study is titled, ‘MSH6 and PMS2 Germline Pathogenic Variants Implicated in Lynch Syndrome are Associated with Breast Cancer.’

Tumor Mutational Burden and Response to Immune Checkpoint Therapy

Predicting how patients will respond to anti-cancer therapies can be vital in informing clinical decisions and improving treatment outcome.  Researchers at Rutgers Cancer Institute of New Jersey examined an association between mutational burden and response to immune checkpoint therapy in several cancer types and found that a mutational burden threshold exists in eight cancers that predict response to an immune checkpoint blockade.

The work’s co-corresponding authors Shridar Ganesan, MD, PhD, associate director for translational science and chief of molecular oncology at Rutgers Cancer Institute, the Omar Boraie Chair in Genomic Science, and  associate professor of medicine and pharmacology at Rutgers Robert Wood Johnson Medical School; and  Rutgers Cancer Institute research member Gyan Bhanot, PhD, professor of molecular molecular biology and biochemistry and professor of physics in the School of Arts and Sciences at Rutgers University, along with lead author Anshuman Panda, MPhil, a Rutgers Physics Department graduate student, share more about the work, published in the December 7 online edition of JCO Precision Oncology (DOI: 10.1200/PO.17.00146): 

Q:  Why is this topic important to explore?

A:  Immune checkpoint blockade therapies have recently been in the news as novel ways to target a variety of cancers. However, these therapies are very expensive and have significant side effects. Furthermore, not all patients respond to such therapy. It is therefore important to identify markers of response for these therapies in relation to the various cancer types to improve treatment efficacy.

Q:  Describe the research and your findings.

A:  We analyzed mutation and gene expression data for more than 9,000 tumor samples from 33 solid tumor types using data from The Cancer Genome Atlas (TCGA) to test whether a high mutational burden is associated with a signature of a blocked immune response. We found that such a mutational burden threshold, which we call the iCAM threshold, exists in eight solid tumors, namely melanoma, lung, colon, stomach adenocarcinoma, endometrial, bladder-urothelial and cervical cancer, and ER+HER2− breast cancer. The efficacy of this threshold in predicting response to anti-immune checkpoint blockade therapy was validated in published data for melanoma, colon and lung adenocarcinoma as well as in a large prospective cohort of 113 samples from Rutgers Cancer Institute and the Vanderbilt Ingram Cancer Center. We also showed that the iCAM threshold is identifiable with high accuracy using routine sequencing assays, such as the FoundationOne and StrandAdvantage assays. Finally, we find that iCAM+ and iCAM- tumors have very distinct mutational profiles, suggesting these are distinct diseases driven by different biological pathways.

Q:  What are the implications for future treatments with checkpoint therapy drugs?

A: The iCAM threshold provides a simple, cost-effective way to identify patients likely to respond to immune checkpoint therapy in eight cancer types using routine sequencing assays currently used in clinical practice.

Phase III Immunotherapy Trial for Migraine Shows Positive Results

An antibody therapy against a key inflammatory molecule involved in migraines reduces the number of headaches that chronic migraine patients experience per month in a phase III trial.

A new study of fremanezumab, an immunotherapy that counteracts one of the molecules released during migraine, was found successful in reducing the number of days that chronic migraine sufferers experienced headaches. The results of the phase III clinical trial were published November 29, 2017 in the New England Journal of Medicine.

The World Health Organization estimates that between 127 and 300 million people around the world experience chronic migraine, defined as 15 or more headaches per month for at least three months. The disease can be debilitating and although a number of interventions exist, many only work for a certain time before they fail to prevent or relieve pain.

“This therapeutic approach offers new hope for people whose migraines cannot be treated with existing medicine,” says Stephen D. Silberstein, M.D., principal investigator of the HALO CM trial, Professor of Neurology and Director of the Jefferson Headache Center at the Vickie & Jack Farber Institute for Neuroscience at Thomas Jefferson University Hospital. “Our worldwide effort to evaluate this novel therapeutic approach has shown positive results and was safe in patients.”

Fremanezumab, a monoclonal antibody developed by Teva Pharmaceuticals, is a biological agent that binds to and blocks the action of a migraine-associated protein called calcitonin gene-related peptide (CGRP). Mounting evidence of its importance in migraines has made CGRP a focal point of research and drug development. The peptide is released at high levels during migraine in response to inflammation, and triggers a cascade effect that stimulates more CGRP release. This results in increasing sensitivity of the brain to pain. By blocking this peptide, doctors hope to break the cycle of increasing inflammation and increased pain sensitivity that contributes to migraine headaches.

Researchers from 132 sites across nine countries enrolled 1130 patients and randomly assigned them to one of three groups: one that received quarterly treatments, a group that received one treatment per month, and one that received placebo injections. The trial lasted for 16 weeks, with a 12-week treatment window.

The results of the trial show that treatment with fremanezumab reduced the number of days patients experience headache by an average of 4.3 days with quarterly treatment and 4.6 days with monthly treatment. “We saw some patients with 100 percent reduction in migraine, others with 75 percent reduction,” says Dr. Silberstein. The level of response varied between patients.

The researchers also looked at how well the therapy worked relative to each patient’s headache burden. They calculated the percent of patients who had more than a 50 percent reduction in the number of days they experienced either a severe or moderate headache per month. Using this measure, the researchers saw that 37.6 percent of patients on the monthly regimen, and 40.8 percent on the quarterly regimen had at least a 50 percent reduction in the number of moderate headaches per month, compared to 18.1 percent in the placebo group.

The therapy had a favorable safety profile with the most common adverse event reported as irritation at injection site, which was reported in the placebo group as well.

“If approved, this treatment would provide physicians with an important new tool to help prevent migraine, reduce a patient’s migraine load, and potentially help patients return to normal” says Dr. Silberstein.

2-Drug Combination May Boost Immunotherapy Responses in Lung Cancer Patients

Johns Hopkins Kimmel Cancer Center researchers and colleagues have identified a novel drug combination therapy that could prime nonsmall cell lung cancers to respond better to immunotherapy. These so-called epigenetic therapy drugs, used together, achieved robust anti-tumor responses in human cancer cell lines and mice.

During the study, published Nov. 30, 2017, in the journal Cell, a team of researchers led by graduate student Michael Topper; research associate Michelle Vaz, Ph.D.; and senior author Stephen B. Baylin, M.D., combined a demethylating drug called 5-azacytidine that chemically reignites some cancer suppressor genes’ ability to operate, with one of three histone deacetylase inhibitor drugs (HDACis). The HDACis work against proteins called histone deacetylases that are involved in processes, such as cell copying and division, and can contribute to cancer development. The combination therapy triggered a chemical cascade that increased the attraction of immune cells to fight tumors and diminished the work of the cancer gene MYC. Based on these findings, investigators have launched a clinical trial of the combination therapy in patients with advanced, nonsmall cell lung cancer.

The development of therapeutic approaches for patients with lung cancer has been a critical medical need, says Baylin, the Virginia and Daniel K. Ludwig Professor of Cancer Research at the Kimmel Cancer Center. While immune checkpoint therapy has been “a tremendous step forward, less than half of patients with lung cancer have benefited to date,” he says.

“In our study, the two-drug epigenetic therapy combination worked exceedingly well, even before putting in the immune checkpoint inhibitors,” Baylin says. “In animal models of lung cancer, the two agents either prevented cancer from emerging or blunted the effects of more aggressive cancers. In both scenarios, a large component of the results involved an increase in immune recognition of the tumors.”

In a series of experiments, researchers studied the combination of 5-azacytidine with the HDACis entinostat, mocetinostat or givinostat in human cancer cell lines and in mouse models of nonsmall cell lung cancers. The treatments were found to alter the tumor microenvironment. In cancer cell lines, 5-azacytidine worked against the cancer gene MYC, causing down regulation of the entire MYC signaling program. Adding the HDACis further depleted MYC, and together the drugs subsequently caused actions that prevented cancer cell proliferation, simultaneously attracted more immune system T cells to the area of the tumor and activated these cells for tumor recognition.

In mouse models, the strongest response was observed when using 5-azacytidine plus givinostat. In one mouse model with a mutant form of nonsmall cell lung cancer, this drug combination given for three months yielded prevention of benign, precursor tumors from becoming cancers and caused 60 percent reduction of overall area of benign tumor appearance in the lungs. By contrast, a group of mice with the same form of lung cancer that were given a mock treatment universally developed large, cancerous lesions in the lungs.

In a second model of mice with established, aggressive, nonsmall cell lung cancer, treatment with an alternating schedule of 5-azacytidine with givinostat and of 5-azacytidine with mocetinostat not only reduced the growth of established, rapidly growing primary tumors but also dramatically reduced metastatic occurrence.

Baylin and colleagues at Memorial Sloan Kettering Cancer Center in New York and Fox Chase Cancer Center in Philadelphia have started a phase I/Ib clinical trial to evaluate if giving mocetinostat with a 5-azacytidinelike drug called guadecitabine can boost immune checkpoint therapy responses in patients with advanced, nonsmall cell lung cancers. The trial is part of the Van Andel Research Institute–Stand Up To Cancer Epigenetics Dream Team and is funded by Merck through the Stand Up To Cancer  (SU2C) Catalyst program, an initiative led by SU2C to bring innovative cancer treatments to patients quickly. Matthew Hellmann, M.D., an author on the paper, will lead this trial at Memorial Sloan Kettering, and Jarushka Naidoo, M.B.B.Ch., assistant professor of oncology, will lead at Johns Hopkins. For more information, click here.

Researchers show stress suppresses response to cancer treatments

New research shows that chronic stress suppresses the immune system’s response to cancer, reducing the effectiveness of immunotherapy treatments.

University of Queensland scientists say they are investigating dual therapies for patients to reduce stress signalling and improve their response to treatments.

UQ Diamantina Institute researcher Dr Stephen Mattarollo said lymphoma progressed more rapidly in mouse models when stress pathways were induced to reflect chronic psychological stress.

“When we used immunotherapies on these mice they were not able to respond as effectively as those which had not been stressed,” Dr Mattarollo said.

“This is because the stress led to poor function against the cancer by T-cells, which are very important in the immune system’s control and surveillance of tumours and are a major target in many immunotherapy treatments.”

Dr Mattarollo said increased anxiety was natural with a cancer diagnosis, and it should be managed to ensure the best possible outcome for patients.

“Absolutely there is now pre-clinical evidence to suggest that treatments and lifestyle interventions to manage or reduce stress levels will improve the chances of these patients responding to therapies,” he said.

“This applies particularly to immunotherapies, but many conventional therapies such as chemotherapy also rely on components of the immune system for their effectiveness.

“It is quite possible that by increasing the immune function in patients they will also respond better to some other therapies.”

PhD candidate Michael Nissen said as immunotherapies became more widely available, it was important to build on the knowledge of factors which influence their effectiveness.

“The more we know, the better chance we have of designing them effectively and efficiently to work in cancer patients,” Mr Nissen said.

Dr Mattarollo said the lab was hoping to combine immunotherapy treatments with commonly used blood pressure drugs that block the effects of stress hormones.

“We hope this will reduce the stress-induced neural signalling and improve immune function,” Dr Mattarollo said.

“We are about to test this combination in animal models.”

Dr Mattarollo said psychoneuroimmunology – or the interaction between the mind, the nervous system and the immune system – is a rapidly growing discipline and is becoming an increasing focus of the lab’s cancer research.

The research is published in Cancer Immunology Research.

Dr Mattarollo’s lab is located at the Translational Research Institute.

New strategy for multiple myeloma immunotherapy

In recent decades monoclonal antibody-based treatment of cancer has been established as one of the most successful therapeutic strategies for both solid tumors and blood cancers. Monoclonal antibodies (mAb), as the name implies, are antibodies that are made by clonal cells derived from a single parent cells and therefore share the identical amino acid sequences.

One of the leading technologies to emerge in mAb-based treatment is CAR-T, where CAR stands for “chimeric antigen receptor”, and T represents T cells, a type of white blood cells that have pivotal roles in immune defenses. CARs are produced by combining together the gene for an antibody that recognizes a tumor antigen with the gene for a receptor that resides on the surface of the T cells; insert this new gene into a T cell and it will be precisely targeted at the tumor.

Theoretically, new antigens – molecules capable of inducing an immune response to produce an antibody – that arise from cancer-specific mutations of cell-surface proteins are excellent targets. However, mAb therapy targeting such antigens is impractical because of these proteins’ vast diversity within and between individual tumors, which renders identifying new cancer-specific target antigens difficult.

However, such challenges have driven researchers centered at Japan’s Osaka University to think outside of the box; cancer-specific antigen formed by the modification of proteins during or after synthesis, such as glycosylation (attachment of sugar moieties to protein) or conformational changes, might have been missed in previous analyses. The team believed new antigen epitopes, which is the part of an antigen recognized by the immune cells, could be discovered by thoroughly searching for cancer-specific mAbs and characterizing the antigens they recognize.

“We applied this strategy to identify novel therapeutic targets for multiple myeloma (MM), a cancer that forms in a type of white blood cell called a plasma cell,” explains Naoki Hosen, lead author of the study, which was recently published in Nature Medicine. “Despite advances in MM treatment, relapse remains common. As such, there is an ongoing need for new therapeutic approaches, including mAb-based therapies.”

The team screened more than 10,000 anti-MM mAb clones and identified MMG49 as an MM-specific mAb specifically recognizing a subset of integrin β7, a cell-surface receptors that facilitate cell-extracellular matrix adhesion. MMG49 reacted to MM cells, but not other bone marrow cell types in MM patient samples. This prompted the researchers to design a CAR that incorporates a fragment derived from MMG49. The resulting MMG49 CAR T was found to have anti-MM effects without damaging normal blood cells.

“Our results also demonstrate that the active conformer of integrin β7 can serve as an immunotherapeutic target against MM, even though the expression of the protein itself is not specific to MM,” study coauthor Yukiko Matsunaga says. “Therefore it’s highly plausible that there are other cancer immunotherapeutic targets that have yet to be identified in many cell-surface proteins that undergo conformational changes, even if the expression of the proteins themselves is not cancer-specific.”

Over the Counter Pain Medication as Effective as Opioids in ER Patients-Study

Emergency rooms are where many patients are first introduced to powerful opioid painkillers, but what if doctors offered over-the-counter pills instead? A new study tested that approach on patients with broken bones and sprains and found pain relievers sold as Tylenol and Motrin worked as well as opioids at reducing severe pain.

The results challenge common ER practice for treating short-term, severe pain and could prompt changes that would help prevent new patients from becoming addicted.

The study has limitations: It only looked at short-term pain relief in the emergency room and researchers didn’t evaluate how patients managed their pain after leaving the hospital.

But given the scope of the U.S. opioid epidemic — more than 2 million Americans are addicted to opioid painkillers or heroin — experts say any dent in the problem could be meaningful.

Results were published Tuesday in the Journal of the American Medical Association.

Long-term opioid use often begins with a prescription painkiller for short-term pain, and use of these drugs in the ER has risen in recent years. Previous studies have shown opioids were prescribed in nearly one-third of ER visits and about 1 out of 5 ER patients are sent home with opioid prescriptions.

“Preventing new patients from becoming addicted to opioids may have a greater effect on the opioid epidemic than providing sustained treatment to patients already addicted,” Dr. Demetrios Kyriacou, an emergency medicine specialist at Northwestern University, wrote in an accompanying editorial.

The study involved 411 adults treated in two emergency rooms at Montefiore Medical Center in New York City. Their injuries included leg and arm fractures or sprains. All were given acetaminophen, the main ingredient in Tylenol, plus either ibuprofen, the main ingredient in Motrin, or one of three opioids: oxycodone, hydrocodone or codeine. They were given standard doses and were not told which drug combo they received.

Patients rated their pain levels before taking the medicine and two hours later. On average, pain scores dropped from almost 9 on a 10-point scale to about 5, with negligible differences between the groups.

Ibuprofen and acetaminophen affect different pain receptors in the body so using the two drugs together may be especially potent, said Dr. Andrew Chang, an emergency medicine professor at Albany Medical College in upstate New York, who led the study.

He noted that a pill combining ibuprofen and acetaminophen is available in other countries; his findings echo research from Canada and Australia testing that pill against opioids for pain relief.

For cancer patients with HIV, immunotherapy appears safe

A new category of immunotherapies called checkpoint inhibitors that has been highly effective against many different cancers appears safe to use in patients with both advanced malignancies and HIV, a population excluded from earlier trials of such therapies, according to an early-phase trial.

Study Principal Investigator, Dr. Thomas Uldrick of the HIV & AIDS Malignancy Branch at the National Cancer Institute, will present late breaking results from the first 17 patients on a phase I study of pembrolizumab in patients with HIV and advanced cancers Friday at the Society for Immunotherapy of Cancer’s annual meeting in National Harbor, Maryland. The ongoing, multi-site study is being conducted by the NCI-funded Cancer Immunotherapy Trials Network, which is headquartered at Fred Hutchinson Cancer Research Center.

Cancer has become the leading cause of death for people with HIV. But until now, they and their physicians have had little data to guide them on whether they can safely use powerful new anti-cancer drugs called immune checkpoint inhibitors.

“During the development of these drugs, people with HIV were routinely excluded from studies due to concerns that they would not tolerate these medications or perhaps not benefit from them because of their underlying HIV and associated immune dysfunction,” Uldrick said. “The most important first step was to show that this class of drug would be safe in cancer patients with HIV.”

Study participants — who were on standard antiretroviral therapy to control their HIV infections and had various cancers that had failed to respond to standard therapies — received pembrolizumab (Keytruda), known since 2015 as “the Jimmy Carter drug” after it swiftly beat back melanoma that had spread to the former president’s brain and liver.

Pembrolizumab belongs to a type of immunotherapy that blocks a braking system cancers use to tamp down the immune response. Checkpoint inhibitors have been extremely effective in some patients with advanced cancers otherwise thought untreatable. The treatments have received U.S. Food and Drug Administration approval for melanoma, lung cancer, head and neck cancer, Hodgkin’s lymphoma, and kidney and bladder cancers.

“These drugs are the backbone of cancer immunotherapy at present and have been shown to be effective in subsets of virtually every different kind of cancer,” said Fred Hutch immunotherapy researcher Dr. Martin “Mac” Cheever, who leads the Cancer Immunotherapy Trials Network and is senior author of the new study. “For patients with HIV who are using effective antiretroviral therapy and have cancers for which these drugs are approved, there’s no reason not to consider these drugs as standard therapy.”

HIV and cancer

From the earliest days of the AIDS pandemic, Kaposi sarcoma — a rarely seen cancer until then — was one of a trio of cancers known as AIDS-defining malignancies. It, non-Hodgkin lymphoma and, in women, cervical cancer, often signaled that a person’s HIV infection had progressed to full-blown AIDS. People did not die of AIDS, per se. They died of one of these cancers or of infections like pneumocystis pneumonia and toxoplasmosis that took advantage of a weakened immune system.

Since the advent of antiretroviral therapy for HIV in 1996, full-blown AIDS and AIDS deaths have dropped dramatically. But the association between HIV and cancer remains, and not just with the traditional AIDS-defining malignancies. A large study published in the journal Annals of Internal Medicine in 2015 found higher cancer incidence across the board in HIV patients, including lung cancer and Hodgkin lymphoma.

“Globally, more than 35 million people are infected with HIV, and cancer is the number one reason they are dying,” Uldrick said. “Establishing proven effective regimens to manage cancer in people with HIV is critically important.”

The ongoing study will enroll up to 36 patients, and there are plans to include more patients with Kaposi sarcoma, a cancer for which checkpoint inhibitors have not been studied. It is one of the leading causes of cancer deaths in sub-Saharan Africa — where HIV rates are high — and new treatments are sorely needed.

Further study in Kaposi sarcoma

Kaposi sarcoma is caused by the Kaposi sarcoma herpes virus (also known as human herpesvirus 8, or HHV-8) and most commonly appears as lesions on the skin. KSHV can also cause two other B-cell tumors, primary effusion lymphoma and a form of multicentric Castleman disease. Additionally, it can infect blood cells and spread through the bloodstream to infect other cells in the body, Uldrick said.

Also to be presented Friday is the death of one patient later in the study who had Kaposi sarcoma. The death is still being evaluated but was likely due to dissemination of KSHV. Uldrick and Cheever said review of the case suggests the patient had a history of symptomatic KSHV viremia, and the study has been changed to exclude such patients in the future and provide specific guidelines for management should new symptomatic KSHV viremia be observed.

Six other study participants with Kaposi sarcoma or primary effusion lymphoma have been treated on this study. None has experienced similar problems, and some have benefitted from therapy, Uldrick said.

“We do not believe that this takes away from the safety message in patients with HIV and other, better studied cancers,” Uldrick said. “However, more experience is clearly needed in treating KSHV-associated diseases with checkpoint inhibitors.”

A passion to ‘change the culture’

Although the NCI has recommended including people with HIV in immunotherapy clinical trials for a decade, virtually every industry-sponsored study over the last five years excluded them, according to a review by Uldrick and others published in the Journal of Clinical Oncology. Uldrick believes that reluctance to include people with HIV in cancer immunotherapy studies dates back to a time when patients were still dying of opportunistic infections and antiretroviral therapies were more toxic than they are today.

As a physician-scientist who focuses on immunology, virology and cancer, Uldrick became frustrated with the lack of data.

“The culture was slow to change,” he said. “It was preventing the advance of appropriate clinical therapies.”

Dr. Holbrook Kohrt, a Stanford oncologist and researcher, shared that frustration. Kohrt instigated the current clinical trial, according to Cheever, driven by his boyhood experience being one of only two hemophiliacs in a special summer camp who did not die of AIDS. (The genetic disorder impairs the blood’s clotting ability and requires infusions of lifesaving clotting factor, which at that time was made from the pooled blood of tens of thousands of donors. Before a test was developed to detect HIV in blood, about half the hemophiliacs in the United States died of AIDS from infected clotting factor.)

“Holbrook had three patients early on with malignancies that he thought would benefit from [checkpoint inhibitors] and could not get access to the drug because they had HIV,” Cheever said. “He was passionate about this study because he was a passionate individual and physician. But he was also influenced by his experience as someone with hemophilia who lost so many peers to HIV.”

Kohrt died in 2016 from complications of hemophilia. He is named as an author of the study.

“He would have predicted these results,” Cheever said.

Getting out the message

The ongoing study is now being conducted at eight sites, each of which includes physician-researchers with expertise in both cancer and HIV. A majority of the early patients were enrolled on the trial through Uldrick’s group at the NCI Intramural Research Program in Bethesda, Maryland.

Uldrick will continue to lead the study after he leaves the NCI to become deputy head of Fred Hutch Global Oncology on Dec. 1.

He and Cheever are hoping that these early results lead to additional studies of checkpoint inhibitors in people with HIV and malignancies, especially those cancers that are more prevalent in people with HIV such as Kaposi sarcoma and cancers caused by another virus, human papillomavirus, such as cervical cancer.

In the meantime, the researchers intend to talk about their findings at multiple scientific communities so that people with HIV and their physicians become aware of the data.

“We’d recommend that patients with HIV and malignancy be considered for this therapy if it’s approved for their particular cancer,” Uldrick said.

Trained T-Cells to Target Toxic Viruses in Pediatric Patients New Cellular Therapy Approach for Children with Compromised Immune Systems

Michael Pulsipher, MD, of the Children’s Center for Cancer and Blood Diseases at Children’s Hospital Los Angeles, along with Michael Keller, MD from Children’s National Health System in Washington, DC, have been awarded $4.8 million by the California Institute for Regenerative Medicine (CIRM) to study the use of a new T-cell therapy to help fight active viral infections in children with severe immune deficiencies. In what will be the largest multi-center pediatric clinical trial of this kind to date, investigators will test the feasibility of using “viral specific” T-cells that are engineered to target three common and potentially toxic viruses: Epstein-Bar virus (EBV), cytomegalovirus (CMV) and adenovirus.

In healthy individuals infections with EBV, CMV and adenovirus cause fatigue, sore muscles, sore throat and swollen glands, but after a short period they recover. For children with weakened immune systems, however, infection with these viruses can lead to severe organ damage or death.

“When patients have severe inherited immune deficiencies or are intensely immune suppressed after a bone marrow transplant, standard antiviral medications are sometimes not enough and patients can die from common viral infections,” explained Pulsipher. “Patients often need at least some function of their own immune systems in addition to antiviral medications in order to clear these infections, but sometimes the patient’s own T-cells are not up to the task.”

Previous studies have demonstrated success in restoring immunity against a particular virus by using donor T-cells that are engineered to target a specific virus for therapy following BMT.

For the new clinical trial, Pulsipher, Keller and their collaborators will use T-cells from healthy donors that have been trained and expanded to target the viruses, then preserved in a donor “bank” for use in the trial. The cells are then individually matched to specific patients based upon their genetic make-up and the viral infection they are experiencing, and shipped to individual centers for infusion. After infusion, the virus-specific targeted T-cells can not only control the active infection, but can help prevent other infections.

“It is our hope that with these trained T-cells, we can help the most vulnerable patients fight off life-threatening viral infections,” said Keller. “By offering a ‘donor’ bank, we are significantly expanding the reach of this therapy and increasing access to even more children, which is extremely exciting.”

“Our study design is to use a multi-virus T-cell therapy to reconstitute immunity against all three of these viruses,” said Pulsipher. “Restoring immunity against multiple viruses simultaneously provides patients with protection from severe viral infections and reduces the need for continued prophylaxis with pharmacotherapy drugs after transplant which can have adverse effects.”

The study, which is expected to include up to 30 centers, will be run through the Pediatric Blood and Marrow Transplant Consortium (PBMTC) Operations Center at CHLA and was developed and is being performed in collaboration with the Primary Immune Deficiency Treatment Consortium (PIDTC). Cell manufacturing for use in the clinical trial will be conducted by the Program for Cell Enhancement and Technologies for Immunotherapy (CETI) of the Children’s National Health System.

FDA Approves the Roll-Over Combination Study with Checkpoint Inhibitor Immunotherapies to Allow Continued Access to BriaVax™ in Patients with Advanced Breast Cancer

The FDA has approved the roll-over combination study of the investigational breast cancer vaccine, BriaVax™ with pembrolizumab {Keytruda; manufactured by Merck & Co., Inc. or ipilimumab {Yervoy; manufactured by Bristol-Myers Squibb Company for patients previously treated with BriaVax™ from the ongoing Phase I/IIa Clinical Trial in Advanced Breast Cancer.

BriaVax™ is a whole-cell breast cancer vaccine genetically engineered to release granulocyte-macrophage colony-stimulating factor (GM-CSF), a substance that activates the immune system by allowing the body to recognize and eliminate cancerous cells by inducing tumor-directed T cell and potentially antibody responses.

This roll-over combination study allows the patients who did not respond to BriaVax™ (monotherapy) treatment to be treated and continue to receive the potential clinical benefits of the vaccine in combination with either pembrolizumab or ipilimumab. This approach is based on the hypothesis that both pembrolizumab and ipilimumab may improve the anti-tumor activity of vaccine in patients with advanced breast cancer. Safety and efficacy data will be evaluated.

“We are very excited to evaluate the effects of BriaVax™ with other approved anti-tumor immunotherapeutic agents. We expect this study to extend and potentiate the clinical benefits of BriaVax™ in advanced breast cancer patients,” stated Dr. Williams, BriaCell’s President & CEO in a press release. “We look forward to expanding our clinical study and exploring potential immunotherapy partnerships with leading pharmaceutical companies in the future, and we are pleased with the FDA decision,” Dr. Williams added.

The clinical investigators will work closely with Cancer Insight, LLC, BriaCell’s contract research organization, to manage the clinical and regulatory aspects of the clinical trial for the roll-over combination study of BriaVax™ on behalf of BriaCell. More information on the roll-over combination study of BriaVax™ with either ipilimumab or pembrolizumab will be available on ClinicalTrials.gov (Study identifier: BRI-ROL-001).

Manufactured by Merck & Co., Inc., KEYTRUDA® (pembrolizumab) is a prescription medicine that may treat certain cancers by working with the immune system. It has been approved for the treatment of a number of cancer indications excluding breast cancer.

Manufactured by Bristol-Myers Squibb Company, YERVOY® (ipilimumab) is a prescription medicine used in adults and children 12 years and older to treat melanoma (a kind of skin cancer) that has spread (metastatic) or cannot be removed by surgery (unresectable). It is a monoclonal antibody that works to activate the immune system and enabling them to recognize and destroy cancer cells.

BriaVax™ is a whole-cell breast cancer vaccine genetically engineered to release granulocyte-macrophage colony-stimulating factor (GM-CSF), a substance that activates the immune system. Previously, a small Phase I study documented very prompt and near complete regression of metastatic breast cancer deposits in the breast, lung, soft tissue, and even the brain.

The ongoing open-label Phase I/IIa study will evaluate BriaVax™ in up to 40 advanced breast cancer patients. This trial is listed in ClinicalTrials.gov as NCT03066947. The trial is being conducted along with the co-development of BriaDx™, our companion diagnostic test. The interim data for the first 10 patients is expected by the first quarter of 2018.

BriaCell is an immuno-oncology focused biotechnology company developing a targeted and safe approach to the management of cancer. BriaCell’s mission is to serve late-stage cancer patients with no available treatment options.

Immunotherapy has come to the forefront of the fight against cancer, harnessing the body’s own immune system in recognizing and selectively destroying the cancer cells while sparing normal ones. Immunotherapy, in addition to generally being more targeted and less toxic than commonly used types of chemotherapy, is also thought to be a strong type of approach aimed at preventing cancer recurrence.

The results of two previous Phase I clinical trials (one with the precursor cell line not genetically engineered to produce GM-CSF and one with BriaVax™) have been encouraging in patients with advanced breast cancer. Most notably, one patient with metastatic breast cancer responded to BriaVax™ with substantial reduction in tumor burden including lung and brain metastases. The company is currently conducting a Phase I/IIa clinical trial for BriaVax™ in patients with advanced breast cancer whose disease has progressed following at least one prior treatment course.

This trial is listed in ClinicalTrials.gov as NCT03066947.  The trial is being conducted along with the co-development of BriaDx™, our companion diagnostic test. The interim data for the first 10 patients is expected by the first quarter of 2018.

In a previous Phase I setting, a patient with metastatic breast cancer responded to BriaVax™ with objective reduction in tumor burden. To expand on this finding, after updating the clinical protocol of the original investigational new drug (IND) application, an open-label Phase I/IIa clinical trial enrolling up to 40 late stage breast cancer patients with recurrent and/or metastatic disease has been launched. Patients will be administered BriaVax™ every two weeks for the first month of treatment, then monthly up to one year.

The primary objective of the Phase I/IIa clinical trial is to evaluate the safety of BriaVax™ in study subjects, and the principal secondary objective is an evaluation of the tumor size reduction. Tumor response will be monitored every three months during the study. The trial will also evaluate progression-free survival (PFS) and overall survival (OS).

For additional details regarding the clinical trial, please visit:
https://www.clinicaltrials.gov/ct2/show/NCT03066947

New molecule shows promise in HIV vaccine design

Researchers at the University of Maryland and Duke University have designed a novel protein-sugar vaccine candidate that, in an animal model, stimulated an immune response against sugars that form a protective shield around HIV. The molecule could one day become part of a successful HIV vaccine.

“An obstacle to creating an effective HIV vaccine is the difficulty of getting the immune system to generate antibodies against the sugar shield of multiple HIV strains,” said Lai-Xi Wang, a professor of chemistry and biochemistry at UMD. “Our method addresses this problem by designing a vaccine component that mimics a protein-sugar part of this shield.”

Wang and collaborators designed a vaccine candidate using an HIV protein fragment linked to a sugar group. When injected into rabbits, the vaccine candidate stimulated antibody responses against the sugar shield in four different HIV strains. The results were published in the journal Cell Chemical Biology on October 26, 2017.

The protein fragment of the vaccine candidate comes from gp120, a protein that covers HIV like a protective envelope. A sugar shield covers the gp120 envelope, bolstering HIV’s defenses. The rare HIV-infected individuals who can keep the virus at bay without medication typically have antibodies that attack gp120.

Researchers have tried to create an HIV vaccine targeting gp120, but had little success for two reasons. First, the sugar shield on HIV resembles sugars found in the human body and therefore does not stimulate a strong immune response. Second, more than 60 strains of HIV exist and the virus mutates frequently. As a result, antibodies against gp120 from one HIV strain will not protect against other strains or a mutant strain.

To overcome these challenges, Wang and his collaborators focused on a small fragment of gp120 protein that is common among HIV strains. The researchers used a synthetic chemistry method they previously developed to combine the gp120 fragment with a sugar molecule, also shared among HIV strains, to mimic the sugar shield on the HIV envelope.

Next, the researchers injected the protein-sugar vaccine candidate into rabbits and found that the rabbits’ immune systems produced antibodies that physically bound to gp120 found in four dominant strains of HIV in circulation today. Injecting rabbits with a vaccine candidate that contained the protein fragment without the sugar group resulted in antibodies that primarily bound to gp120 from only one HIV strain.

“This result was significant because producing antibodies that directly target the defensive sugar shield is an important step in developing immunity against the target and therefore the first step in developing a truly effective vaccine,” Wang said.

Although the rabbits’ antibodies bound to gp120, they did not prevent live HIV from infecting cells. This result did not surprise Wang, who noted that it usually takes humans up to two years to build immunity against HIV and the animal study only lasted two months.

“We have not hit a home run yet,” Wang noted. “But the ability of the vaccine candidate to raise substantial antibodies against the sugar shield in only two months is encouraging; other studies took up to four years to achieve similar results. This means that our molecule is a relatively strong inducer of the immune response.”

The researchers’ next steps will be to conduct longer-term studies in combination with other vaccine candidates, hone in on what areas of gp120 the antibodies are binding to and determine how they can increase the antibodies’ effectiveness at neutralizing HIV.

Fred Hutch researchers engineer complex immunotherapy that may target relapsing leukemia

Researchers at Fred Hutchinson Cancer Research Center and the University of Washington have developed a novel way to genetically engineer T cells that may be effective for treating and preventing leukemia relapse.

The findings, published online in the journal Blood, provide the basis for launching a first-in-human clinical trial of this new immunotherapy, which relies on engineered T-cell receptors, or TCRs. This immunotherapy represents a different method of genetic engineering than the CAR T-cell therapies that were recently approved by the U.S. Food and Drug Administration.

Relapse occurs in about one-third of patients with acute leukemia who undergo stem cell transplantation to rebuild cancer-free blood cells, and more than 90 percent of these patients die after an average survival of about four months.

“New therapies are desperately needed to prevent and treat relapse of leukemia in patients who have undergone hematopoietic stem cell transplantation,” said pediatric oncologist Dr. Marie Bleakley, the paper’s senior author, who is a member of Fred Hutch’s Clinical Research Division.

T cells, a linchpin of the immune system, have a variety of molecules on their surface, known as receptors, that recognize cells that are foreign or diseased and kill them. To boost the immune system’s ability to recognize and attack these “invaders,” researchers may transfer genes for a tumor-specific T-cell receptor into the T cells collected from a patient’s transplant donor.

In this work, Bleakley and colleagues exploited a specific “minor histocompatibility antigen,” or minor H antigen, found on the surface of leukemia cells in some patients. Using this group of antigens as targets is being re-examined now that the basic principles of cancer immunotherapy are better understood and potent T-cell immunotherapy is a clinical reality. Because these antigens are expressed predominantly on blood-forming cells, targeting them could provide a potent and selective anti-leukemia treatment with little risk to other cells.

TCR therapy differs from CAR T-cell therapy in that the latter involves creating receptors that are not found in nature. The former occurs naturally in humans, though the receptors we have can vary. While CAR T-cell therapies are known to be effective in treating B-cell acute lymphoblastic leukemia, or ALL, it has not yet been successful in acute myeloid leukemia or T-cell ALL.

Bleakley’s team broke new ground by identifying T-cell receptors that were especially potent in their targeting of a minor H antigen found on the surface of leukemia cells. Using these genetic blueprints, they then were able to extract these receptors from select blood samples provided by donors. Next, they inserted these receptors into T cells from donors for patients who could perhaps benefit from having such “supercharged” T cells to seek and destroy cancer cells with the targeted antigen.

Although no patients have yet received these TCRs, the engineered T cells efficiently and specifically killed target cells in laboratory tests.

“T-cell receptors isolated from minor H antigen-specific T cells represent an untapped resource for developing targeted T-cell immunotherapy to manage leukemia relapse,” Bleakley said, adding that the construct used in this study could serve as a prototype for others targeting similar antigens. Her research team has established a new technique to discover antigens that may be exploited as targets and has identified and characterized five novel minor H antigens.

Bleakley is aiming to launch a Phase 1 clinical trial in December 2017. If results from the lab are borne out in clinical trials, this form of adoptive T-cell therapy could join a growing immune-based arsenal. Fred Hutch researchers and clinicians are pioneers in the development of a variety of T-cell therapies for blood-related and other cancers.

Good-Guy Bacteria May Help Cancer Immunotherapies Do Their Job

Individuals with certain types of bacteria in their gut may be more likely to respond well to cancer immunotherapy, researchers at the Harold C. Simmons Comprehensive Cancer Center found in a study of patients with metastatic melanoma.

The incidence of melanoma has been increasing over the past 40 years. Immunotherapies have dramatically improved the outlook for patients with metastatic melanoma in the past half-dozen years, but still only about half of these patients go into remission.

UT Southwestern cancer researchers analyzed the gut bacteria of 39 melanoma patients who were treated with immunotherapies and found a strong association between a good response and the presence of particular bacteria.

“Our research suggests there were certain good-guy bacteria that are needed to optimize the effectiveness of checkpoint inhibitors. These bacteria somehow prime your immune system so that it’s better able to attack cancer cells and kill them,” said senior author Dr. Andrew Koh, Associate Professor of Pediatrics and Microbiology with the Simmons Cancer Center.

Rick Spurr, former CEO of Zix, a company that provides email encryption services for banks and health care facilities, volunteered for the study that helped identify the link. The grandfather of six was diagnosed with metastatic melanoma, which was discovered on his lungs while he was fighting off a bout of pneumonia.

Mr. Spurr was treated with an every-other-week infusion of nivolumab, an immunotherapy drug that acts by lifting a brake on the immune system, allowing the body’s natural defenses to go into overdrive.

“I felt virtually no side effects from the treatment,” he said. “I started the treatment in the summer and I was skiing in November.”

Researchers found he had the beneficial gut bacteria and suspect this microbiome contributed to the outcome. As a group, patients who responded well to the immunotherapy had three specific bacteria:

  • Bacteroides thetaiotaomicron
  • Faecalibacterium prausnitzii
  • Holdemania filiformis

All three are common normal flora in the human intestinal tract.

After identifying the link, researchers looked for a potential reason for the association between the helper bacteria and immunotherapy effectiveness. “Is it something the bacteria are making? We examined metabolites in these subjects and found the strongest correlation between anacardic acid, present in cashews and mangoes, and the beneficial bacteria,” Dr. Koh said.

Researchers plan to follow up on the current research, which appears in the journal Neoplasia, with larger clinical studies.

“While these preliminary observations do not establish a firm causal connection between gut microbes and immunotherapy efficacy, they may lead eventually to a probiotic cocktail that could be given along with immunotherapy to enhance the chance of response,” said Dr. Koh, Director of Pediatric Hematopoietic Stem Cell Transplantation at UT Southwestern.

The research was supported by the Roberta I. and Norman L. Pollock Fund, the Melanoma Research Fund, the T. Boone Pickens Cancer Research Fund, the Cancer Prevention and Research Institute of Texas, and the National Institutes of Health.

The Harold C. Simmons Comprehensive Cancer Center is the only NCI-designated Comprehensive Cancer Center in North Texas and one of just 49 NCI-designated Comprehensive Cancer Centers in the nation. Simmons Cancer Center includes 13 major cancer care programs. In addition, the Center’s education and training programs support and develop the next generation of cancer researchers and clinicians. Simmons Cancer Center is among only 30 U.S. cancer research centers to be designated by the NCI as a National Clinical Trials Network Lead Academic Participating Site.

About UT Southwestern Medical Center

UT Southwestern, one of the premier academic medical centers in the nation, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty has received six Nobel Prizes, and includes 22 members of the National Academy of Sciences, 18 members of the National Academy of Medicine, and 14 Howard Hughes Medical Institute Investigators. The faculty of more than 2,700 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in about 80 specialties to more than 100,000 hospitalized patients, 600,000 emergency room cases, and oversee approximately 2.2 million outpatient visits a year.

Confronted with bacteria, infected cells die so others can live, Penn study finds

The immune system is constantly performing surveillance to detect foreign organisms that might do harm. But pathogens, for their part, have evolved a number of strategies to evade this detection, such as secreting proteins that hinder a host’s ability to mount an immune response.

In a new study, a team of researchers led by Igor E. Brodsky of the University of Pennsylvania, identified a “back-up alarm” system in host cells that responds to a pathogen’s attempt to subvert the immune system.

“In the context of an infection, the cells that are dying are talking to the other cells that aren’t infected,” said Brodsky, an assistant professor in the Department of Pathobiology in Penn’s School of Veterinary Medicine and senior author on the study. “I don’t think of it as altruistic, exactly, but it’s a way for the cells that can’t respond any longer to still alert their neighbors that a pathogen is present.”

The findings address the long-standing question of how a host can generate an immune response to something that is designed to shut off that very response. A potential future application of this new understanding may enable the cell-death pathway triggered by bacteria to be harnessed in order to target tumor cells and encourage their demise.

The work appears in the Journal of Experimental Medicine.

A major way that the immune system recognizes pathogens is by detecting patterns that are shared among microbes but are distinct from a host’s own cells. Pathogens, however, don’t make it easy for immune cells to destroy them. Some can inject proteins into host cells that interfere with this detection, allowing an infection to become established.

Yersinia bacteria, certain species of which cause plague and gastrointestinal disease in humans, is one such pathogen. These bacteria inject a protein, YopJ, into immune cells, that interferes with key signaling pathways, thereby blocking the production of cytokines that could otherwise communicate with other cells about the infection and inducing apoptosis, a form of cell death, which had generally been thought to be non-inflammatory — in other words, a quiet death.

Yet humans and mice can survive Yersinia infections because somehow their immune systems become aware of the presence of an invader.

To understand how host cells overcome Yersinia’s insidious strategy, Brodsky’s team focused on the activity of an enzyme called RIPK1. RIPK1 was known to play a key role in signaling in respose to an immune cell detecting pathogen-associated patterns as well as inducing cell death.

“RIPK1 sits at a key decision point for the cell,” Brodsky said. “Depending on the stimuli the cells see, this protein can transduce a signal to activate gene expression, programmed cell death, or apoptosis, or it can activate another form of cell death called programmed necrosis.”

Two recent papers in Nature Cell Biology describe the mechanism of how RIPK1 helps a cell switch between pro-survival and pro-death functions. And while it was known that interfering with this pathway can induce cells to die, there had never been a good physiological explanation for why that should be the case.

The researchers relied upon a strain of mouse, created by GlaxoSmithKline, that possesses a specific mutation in RIPK1 that renders the enzyme unable to trigger the apoptosis pathway upon encountering Yersinia bacteria.

“This mouse was really useful for us to be able to distinguish between the inflammatory response and apoptosis,” Brodsky said.

When these mice were infected with Yersinia, their cells did not undergo apoptosis. Instead, these animals became extremely sensitive to infection, succumbing to an infection that normal mice almost always survive. Bacteria could be found dispersed throughout the body, whereas in normal mice Yersinia was typically confined to the lymph nodes, spleen and liver.

“They were unable to control the bacterial burden,” Brosky said. “The bacteria disseminated systemically, including to the lungs.”

While apoptosis is normally considered non-inflammatory, the researchers showed that RIPK1-induced apoptosis itself promotes cytokine production, presumably by uninfected bystander cells, which helps in recruiting an inflammatory response and plays a role in promoting survival of the host.

The researchers also noticed that the infected lymph nodes from mice that could not undergo RIPK1-induced apoptosis were unable to form granulomas, areas of organized immune cells that can form in response to many infectious or inflammatory stimuli, and are thought to be places of bacterial containment. This suggested that RIPK1-induced apoptosis might promote containment of the bacteria by allowing the immune system to form these granulomas.

Though Brodsky said the research is still at an early stage, one possible therapeutic implication of the work could serve as a way to push cancer cells, which typically grow and thrive without hindrance from the immune system, to their own death.

“We could imagine that modifying bacteria that trigger these pathways, or delivering this bacterial protein to tumor cells, could be potentially useful as an anti-cancer therapeutic,” he said.

In future work, Brodsky and colleagues will further investigate the signals that infected cells release in order to start cytokine production by bystander cells. They hope to decipher which molecular pathways are most important in the process. The researchers would also like to develop a more detailed understanding of how granulomas form.

Drug Combo Gangs Up to Take on Triple-Negative Breast Cancer

Researchers find novel combination disrupts multiple factors in aggressive type of cancer

In the hunt for novel treatments against an aggressive form of breast cancer, researchers combined a new protein inhibitor with a chemotherapy drug to create a powerful combination that resulted in cancer cell death.

Triple-negative breast cancer is a subtype that does not express hormone receptor or HER2. It occurs in approximately 15 percent of patients with breast cancer. This subtype tends to be more aggressive and targeted therapeutic treatment options are lacking.

In this work, the drugs studied were each tested separately in triple-negative breast cancer cell lines and in mice with the disease. The researchers then implemented the treatments in combination. The combination produced a synergistic effect that was more effective than either drug alone. The cancer cells treated with the drug combination were less likely to multiply or spread in cell culture and were less viable in an animal model.

Preliminary data had shown that inhibiting proteins called cyclin dependent kinases, or CDKs, might be effective against triple negative breast cancer. In this study, researchers tested a pharmaceutical grade CDK inhibitor called CYC065. Additionally, researchers used the chemotherapy drug eribulin, which had shown promise in prior clinical trials for the treatment of triple-negative breast cancer.

“In this pre-clinical study, we showed that the combination of CYC065 and eribulin had a synergistic effect against the growth and progression of triple-negative breast cancer. New therapeutic targets and treatment strategies are crucial to improve outcomes for women with this aggressive breast cancer subtype,” says study author Jacqueline S. Jeruss, M.D., Ph.D., director of the Breast Care Center at the University of Michigan Comprehensive Cancer Center.

From the early days of her career, Jeruss was interested in how signaling pathway alterations could impact the development of breast cancer. What makes a mammary cell change to allow for lactation but then regress when that function is no longer needed? What orchestrates cell regulation to allow for such carefully mediated physiologic changes? And what processes occur over time that cause the cellular deregulation leading to cancer development in certain patients, but not in others?

Her work led her to the implementation of CDK inhibitors for the treatment of triple negative breast cancer. She found that these drugs could help to block the harmful impact of overexpression of cancer promoting cyclin E/CDKs, proteins that were inhibiting the tumor suppressant action of the TGF-beta/SMAD3 pathway. CDK inhibitors can block the impact of cyclin E/CDK action, helping to restore the beneficial effects of the TGF-beta/SMAD3 pathway, and thus facilitating cancer cell death.

In the current study, published in Oncotarget, the combination treatment of the CDK inhibitor CYC065 with the chemotherapy eribulin, resulted in less viable triple negative breast cancer cells, smaller tumor colonies, decreased cell migration, and small tumor size in an animal model.

Researchers also identified specific transcription factors that were impacted by CYC065. These processes likely work together to promote cancer cell death.

“We have begun to identify a network of vulnerable and targetable signaling components within the triple negative cancer cells that can be exploited with CDK inhibitor and chemotherapy treatment to promote triple negative breast cancer cell death,” Jeruss says.

The research was done with triple negative breast cancer cells in culture and in an animal model. The next step is for researchers to develop a clinical trial to test the drug combination in patients with triple-negative breast cancer.

Drug targeting technique could aid therapies for immune diseases

A new technique that targets drugs to specific cells could lead to improved therapies for diseases caused by an overactive immune response.

The approach could help people affected by conditions such as arthritis and inflammatory bowel diseases, where the body’s own immune system mistakenly attacks healthy tissues.

Researchers focused on a group of immune cells called macrophages – some of which help the body heal after injury, while others can promote harmful inflammation.

The team at the University of Edinburgh sought to devise a new therapy to remove harmful macrophages while leaving healing cells unaffected

They coupled a drug compound to a carrier molecule that only becomes active in acidic conditions, such as those found inside harmful macrophages.

A fluorescent tag attached to the molecules enabled the team to track the cells affected by the drug.

Lab tests on human macrophages showed the treatment preferentially affected inflammatory macrophages and did not affect healing cells.

Studies with zebrafish, which share features of their immune system with people, found the treatment helped to improve the recovery of tissues after injury.

The team hopes their approach could lead to more effective therapies, with fewer side effects, for the treatment of immune-related diseases.

Their research was published in the journal ACS Central Science.

Dr Marc Vendrell, of the Medical Research Council Centre for Inflammation Research at the University of Edinburgh, who led the study, said: “This is an important step forward in the design of more precise drugs with fewer side effects. In future studies, we want to exploit this technology to improve the treatment of diseases in which macrophages and immune cells are important.”

Immune cells may heal bleeding brain after strokes

While immune cells called neutrophils are known to act as infantry in the body’s war on germs, a National Institutes of Health-funded study suggests they can act as medics as well. By studying rodents, researchers showed that instead of attacking germs, some neutrophils may help heal the brain after an intracerebral hemorrhage, a form of stroke caused by ruptured blood vessels. The study suggests that two neutrophil-related proteins may play critical roles in protecting the brain from stroke-induced damage and could be used as treatments for intracerebral hemorrhage.

“Intracerebral hemorrhage is a damaging and often fatal form of stroke for which there are no effective medicines,” said Jaroslaw Aronowski, M.D., Ph.D., professor, department of neurology, at the University of Texas Health Science Center at Houston, and senior author of the study published in Nature Communications. “Our results are a hopeful first step towards developing a treatment for this devastating form of stroke.”

Accounting for 10 to 15 percent of all strokes, intracerebral hemorrhages happen when blood vessels rupture and leak blood into the brain, often leading to death or long-term disability. Chronic high blood pressure is the leading risk factor for these types of strokes. The initial phase of damage appears to be caused by the pressure of blood leaking into the brain. Over time, further damage may be caused by the accumulation of toxic levels of blood products, infiltrating immune cells, and swelling.

Decades of research suggest that neutrophils are some of the earliest immune cells to respond to a hemorrhage, and that they may both harm and heal the brain. In this study, the researchers found that interleukin-27 (IL-27), a protein that controls the activity of immune cells, may shift the role of neutrophils from harming the brain to helping with recovery.

Injections of IL-27 after a hemorrhage helped mice recover. Days after the strokes, the treated mice had better mobility, including walking, limb stretching and navigating holes in a floor. In contrast, injections of an antibody that blocked natural IL-27 activity slowed recovery. The brains of the mice treated with IL-27 also showed less damage. They had less swelling around the hemorrhages and lower levels of iron and the blood protein hemoglobin, both of which are toxic at high levels.

“This study shines a spotlight on the critical role the immune system may play in helping the brain heal after a hemorrhage or stroke and opens new avenues for stroke treatment strategies,” said Jim Koenig, Ph.D., program director at the NIH’s National Institute of Neurological Disorders and Stroke.

Neutrophils are born in bone marrow and carry chemicals in hundreds of densely filled packets called granules, which look like dark spots under a microscope. Typically, when the body senses bacteria or an injury, neutrophils rush to the invasion site and release germ killing chemicals from the granules. This appears to happen minutes after a hemorrhagic stroke.

In this study, the researchers suggested that after a hemorrhagic stroke the brain secretes high levels of IL-27, which leads to a second wave of neutrophils arriving with granules filled with higher amounts of healing molecules. IL-27 levels were elevated in the brain and blood of the mice an hour after hemorrhages and stayed high for three days, peaking at 24 hours later. Further experiments suggested that brain cells called microglia produced the IL-27 in response to the presence of red blood cells.

Once released, IL-27 molecules appeared to travel to the bones of the mice, infiltrated the marrow, and changed the role newborn neutrophils played in response to a stroke. When the researchers extracted newborn neutrophils from the bones of mice and treated them with IL-27, the chemical raised the activity of genes associated with healing, especially lactoferrin, while reducing the activity of genes associated with killing cells. Conversely, treating mice with an IL-27 neutralizing antibody after a hemorrhage lowered lactoferrin gene activity.

“Our results suggested that IL-27 links the brain to the bones,” said Dr. Aronowski. “We can use these results as a source for ideas for developing potential treatments for hemorrhagic stroke.”

Finally, the researchers showed the iron binding protein lactoferrin may protect the brain from intracerebral hemorrhagic strokes. Mice and rats injected with lactoferrin 30 minutes after hemorrhages recovered faster and had reduced brain damage as compared to animals given placebos. In one set of experiments, the researchers found that giving mice lactoferrin 24 hours after a stroke was also effective.

“Lactoferrin appears to have a long treatment window,” said Dr. Aronowski. “This means lactoferrin might one day be used to help patients recover from intracerebral hemorrhage.”

Dr. Aronowski’s team is taking the next steps towards testing lactoferrin treatment in patients.

Immunotherapy treatment option for selected breast cancer patients, genetic study suggests

Immunotherapy drugs could help some breast cancer patients based on the genetic changes in their tumours, researchers at the Wellcome Trust Sanger Institute and their collaborators find. Published today (13 September) in Cancer Research, scientists identify particular genetic changes in a DNA repair mechanism in breast cancer.

The results open up the possibility to another therapy option for around 1,000 breast cancer patients in the UK, who could benefit from existing drugs.

Breast cancer is the most common cancer in the UK, affecting nearly 55,000 women a year. Globally it accounts for nearly 1.7 million cancer cases.

In the study, scientists found that a particular group of breast cancer patients have genetic changes, or mutations, that occur because of an abnormality of a DNA repair mechanism known as mismatch repair*. These mutations are found in other cancers, such as colorectal cancer, but are rarely looked for in breast cancer.

Colorectal cancers with deficient mismatch repair have recently been treated with immunotherapies called checkpoint inhibitors in the US**, including the drug pembrolizumab. Immunotherapies exploit the fact that, under the influence of check point inhibitors, highly mutated tumour cells can be recognised as ‘foreign’ by the patient’s immune system.

The results of this new study suggest that these immunotherapies could also be effective for some breast cancer patients based on the same mutation patterns seen in their tumours. Therefore clinical trials are required to determine if immunotherapies could help selected breast cancer patients.

In the study, the team analysed the whole genome sequences of 640 breast cancer tumours. They looked for patterns in the mutations, known as mutational signatures, which indicated abnormalities in the mismatch repair mechanism. From the mutational signatures, the team identified 11 tumours that had the mismatch repair defects causing the breast cancer.

Dr Serena Nik-Zainal, lead author from the Wellcome Trust Sanger Institute, said: “We’ve unequivocally found mismatch repair deficient breast cancers. As these tumours have the same mutational signatures as those of other cancers, like colorectal cancer, they should in theory respond to the same immunotherapy drugs. Our results suggest expanding the cohort of cancer patients that could possibly be treated with checkpoint inhibitors to include these mismatch repair deficient breast cancer patients.”

Dr Helen Davies, first author from the Wellcome Trust Sanger Institute, said: “Using whole genome sequencing we can start to stratify breast cancer patients into different categories based on their mutational signatures. Current clinical criteria means these tumours would not have been detected as being deficient in the mismatch repair pathway. We have shown that there is in fact another category of breast cancers – those with defective mismatch repair.”

Professor Karen Vousden, Cancer Research UK’s chief scientist, said: “Immunotherapies have shown promise for some cancer patients, but the challenge for doctors has been predicting which patients they are likely to help. This study, using a technique called whole genome sequencing, reveals more about the genetic patterns that could show which women with breast cancer are more likely to respond to immunotherapy treatments. The next step will be to test this approach in clinical trials to find out if identifying these patterns and using them to tailor breast cancer treatments helps to improve survival.”

Modulating T-Cell Metabolism Uncovers New Technology for Enhancing Immunotherapy

T lymphocytes found in tumors and implicated in killing tumor cells cope with the shortage of oxygen and nutrients in the tumor microenvironment by using fat as the main source of energy. Promoting a switch from glucose to fatty acid to generate energy enhances T cell antitumor activity. These findings from a study conducted at The Wistar Institute were published in the journal Cancer Cell.

The presence of tumor infiltrating T lymphocytes (TILs) in solid tumors is often associated with better clinical outcomes and better patient responses to some immunotherapeutic treatments. These cells can be isolated from a cancer patient, manipulated ex vivo, and infused into the same patient to treat her/his own cancer. However, the effectiveness of TILs antitumor responses is limited by their progressive loss of functions. Metabolic stress plays a central role in the exhaustion of T cells as they compete with tumor cells for oxygen and nutrients in the tumor microenvironment. In these unfavorable conditions, the function of TILs is impaired, reducing their potency against the tumor and the efficacy of T cell-based immunotherapy.

“The mechanisms behind TILs exhaustion are poorly understood,” said lead author of the study Hildegund C.J. Ertl, M.D., Caspar Wistar Professor in Vaccine Research and member of Wistar’s Vaccine & Immunotherapy Center. “Considering the central importance of TILs for cancer immunotherapy, we believe that our findings may have critical implications to boost the efficacy of T cell-based therapies.”

This study by Ertl and colleagues shows that low oxygen levels combined with low glucose availability cause TILs to adapt their metabolism and change their source for energy production from glucose to fatty acids, the building blocks of fat. Further inducing this metabolic shift instructs the T cells to increase their use of fatty acids for energy production, thus improving TILs’ effector functions and their ability to delay tumor progression.

The Ertl lab studied the effectiveness of metabolic manipulations to improve TIL functions in two melanoma mouse models and in the context of two different immunotherapy approaches. Ertl and colleagues confirmed the clinical relevance of these observations by showing that T cells isolated from metastases of melanoma patients have increased fatty acid metabolism compared with circulating lymphocytes from healthy donors. Furthermore, using fibrates, a class of FDA approved drugs used to lower cholesterol levels, they promoted the breakdown of fatty acids and observed that this enforced metabolic switch is associated with improved T cell functions within tumors. Importantly, these drugs can also synergize with immune checkpoint blockade therapy, improving the efficacy of this melanoma immunotherapy.

“Pharmacological interventions aimed at promoting the metabolic adaptation of TILs towards fatty acid metabolism may have a broad implication for T cell-based immunotherapy for different cancer types,” added Ertl.