Finding a Key to Unlock Blocked Differentiation in Microrna-Deficient Embryonic Stem Cells

This aids goal to use stem cells in therapy, where an important hurdle is efficient differentiation.

The more than 200 different types of human cells have the same DNA but express different ensembles of genes. Each cell type was derived from embryonic stem cells, which are called pluripotent stem cells because they can differentiate to all those different cell fates.

One very active area of biology is cells that mimic these fountainhead embryonic stem cells, cells that are called induced pluripotent stem cells, or iPSCs. With genetic and biochemical tricks, researchers can reverse a differentiated cell — such as a skin fibroblast — into a pluripotent state.

Such iPSCs have the potential to create tissue for regenerative medicine, such as repair heart attacks, create models of human disease or make cells that enable drug screening. But future progress with iPSCs needs a much greater understanding of the basic biology of pluripotency and differentiation.

“For the goal of using stem cells in therapy, the most important step is differentiation from iPSCs,” said Rui Zhao, Ph.D., an assistant professor of biochemistry and molecular genetics at the University of Alabama at Birmingham. “We need to be able to differentiate the iPSCs into a disease-relevant cell type at high efficiency and high purity.”

In a study published in Stem Cell Reports, Zhao and colleagues have partly solved a long-unanswered basic question about stem cells — why are pluripotent stem cells that have mutations to block the production of microRNAs unable to differentiate?

Zhao and colleagues, including co-corresponding author Kitai Kim, Ph.D., of the Sloan Kettering Institute, have found a key that allows those microRNA-deficient pluripotent stem cells to differentiate into neural cells, including subtypes with markers for dopaminergic, glutamatergic and GABAergic neurons

“For many years, we did not know why these cells did not differentiate,” Zhao said. The answer for neural cell differentiation in the microRNA-deficient cells turned out to be simple — a single microRNA or a single protein.

In the Stem Cell Reports study, Zhao and colleagues show that a microRNA-302 mimic — delivered by a specially constructed lentivirus — was sufficient to enable neural differentiation of mouse embryonic stem cells that lacked Dgcr8, a vital gene for the processing of the more than 2,000 microRNAs in cells.

When they examined gene expression profiles in the differentiated cells, they saw changes in many gene sets regulated by p53, also known as tumor suppressor p53. This tumor suppressor has been called “the guardian of the genome” because of its many roles in preventing DNA damage and cancer.

Zhao, Kim and colleagues showed that microRNA-302 acted to reduce p53 expression in the microRNA-deficient embryonic stem cells by binding to the 3′ untranslated region of p53 mRNA.

They further showed that direct inhibition of p53 with the simian virus large T antigen or short hairpin RNA, or even deleting the p53 gene itself, allowed embryonic stem cells or iPSCs to proceed to neural differentiation without the need for microRNA-302. Thus, the differentiation barrier that prevents the neuronal lineage specification from microRNA-deficient stem cells is expression of p53.

The keys to unlock the paths cells to other cell lineage specifications from microRNA-deficient embryonic stem are still unknown, Zhao says.

Scientists make a major breakthrough to treat fibrotic diseases that cause organ failure

Researchers from Duke-NUS Medical School (Duke-NUS) and the National Heart Centre Singapore (NHCS) have discovered that a critical protein, known as interleukin 11 (IL11) is responsible for fibrosis and causes organ damage. While it is surprising that the importance of IL11 has been overlooked and misunderstood for so long, it has now been very clearly demonstrated by this work.

A protein known as transforming growth factor beta 12 (“TGFB1”) has long been known as the major cause of fibrosis and scarring of body organs, but treatments based on switching off the protein have severe side effects. The scientists discovered that IL11, is even more important than TGFB1 for fibrosis and that IL11 is a much better drug target than TGFB1.

Fibrosis is the formation of excessive connective tissue, causing scarring and failure of bodily organs and the skin. It is a very common cause of cardiovascular and renal disease, where excessive connective tissue destroys the structure and function of the organ with scar tissue. Compared to other Asians, American, and Europeans, Singaporeans have a higher prevalence of coronary artery disease, hypertension, and diabetes, the three most common diseases that lead to heart failure. In addition, kidney failure is an epidemic in Singapore and around the world. Fibrosis of the heart and kidney eventually leads to heart and kidney failure, thus this breakthrough discovery — that inhibiting IL11 can prevent heart and kidney fibrosis — has the potential to transform the treatment of millions of people around the world.

The international team, led by Professor Stuart Cook, Tanoto Foundation Professor of Cardiovascular Medicine, along with Assistant Professor Sebastian Schäfer, both from NHCS and Duke-NUS’ Programme in Cardiovascular and Metabolic Disorders, carried out the translational research to identify the key drivers of chronic fibrotic disease in heart, kidney, and other tissues. The team also includes researchers from Harvard University and University of California, San Diego/UCSD (USA), Max Delbrück Center for Molecular Medicine/MDC-Berlin (Germany), London Institute of Medical Sciences/MRC-LMS and Imperial College London (the UK), and the University of Melbourne (Australia).

“Fibrotic diseases represent a major cause of illness and death around the world. The discovery that IL11 is a critical fibrotic factor represents a breakthrough for the field and for drug development. It is an incredibly exciting discovery,” explained the study’s senior author, Professor Cook, who is also Director, National Heart Research Institute Singapore.

“Currently, more than 225 million people worldwide suffer from heart and kidney failure and there is no treatment to prevent fibrosis. The team is at the stage of developing first-in-class therapies to inhibit IL11 and this offers hope to patients with heart and kidney disease,” shared Professor Terrance Chua, Medical Director, National Heart Centre Singapore.

“This therapeutic target for fibrotic diseases of the heart, kidney and other organs may be exactly what we need to fill the unmet pressing clinical gap for preventing fibrosis in patients. We are proud to announce that the suite of intellectual property arising from this research has been licensed to a newly launched Singapore-funded biotechnology start-up Enleofen Bio Pte Ltd, which is co-founded by Professor Cook and Assistant Professor Schäfer,” said Professor Thomas Coffman, Dean of Duke-NUS Medical School.

No cardiovascular disease reduction with intensive blood pressure lowering treatment

Blood pressure lowering treatment does not reduce death or cardiovascular disease in healthy individuals with a systolic blood pressure below 140. This is shown in a systematic review and meta-analysis from Umeå University. The results, published in JAMA Internal Medicine, support current guidelines and contradict the findings from the Systolic Blood Pressure Intervention Trial (SPRINT).

Blood pressure treatment goals have been intensively debated since the publication of the SPRINT study in 2015. While current guidelines recommend a systolic blood pressure goal < 140 mm Hg, SPRINT found additional mortality and cardiovascular disease reduction with a goal < 120 mm Hg.

A systematic review and meta-analysis from Umeå University, published today in JAMA Internal Medicine, contradicts these findings. The Umeå study shows that treatment does not affect mortality or cardiovascular events if systolic blood pressure is < 140 mm Hg. The beneficial effect of treatment at low blood pressure levels is limited to trials in people with coronary heart disease.

“Our findings are of great importance to the debate concerning blood pressure treatment goals,” says Dr Mattias Brunström, researcher at the Department of Public Health and Clinical Medicine, Umeå University and lead author.

The study is a meta-analysis, combining data from 74 randomized clinical trials, including more than 300 000 patients. The researchers separated primary preventive studies from studies in people with coronary heart disease or previous stroke. The analysis found that the treatment effect was dependent on how high blood pressure was in previously healthy individuals. If systolic blood pressure was above 140 mm Hg, treatment reduced the risk of death and cardiovascular disease. Below 140 mm Hg, treatment did not affect mortality or the risk of first-ever cardiovascular events.

“Several previous meta-analyses have found that blood pressure lowering treatment is beneficial down to levels below 130 mm Hg. We show that the beneficial effect of treatment at low blood pressure levels is limited to trials in people with coronary heart disease. In primary preventive trials, treatment effect was neutral,” says Mattias Brunström.

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.

Immune Cells Mistake Heart Attacks for Viral Infections

A study led by Kevin King, a bioengineer and physician at the University of California San Diego, has found that the immune system plays a surprising role in the aftermath of heart attacks.  The research could lead to new therapeutic strategies for heart disease.

The team, which also includes researchers from the Center for Systems Biology at Massachusetts General Hospital (MGH), Brigham and Women’s Hospital, Harvard Medical School, and the University of Massachusetts, presents the findings in the Nov. 6 issue of Nature Medicine.

Ischemic heart disease is the most common cause of death in the world and it begins with a heart attack. During this process, heart cells die, prompting immune cells to enter the dead tissue, clear debris and orchestrate stabilization of the heart wall.

But what is it about dying cells in the heart that stimulates the immune system? To answer this, researchers looked deep inside thousands of individual cardiac immune cells and mapped their individual transcriptomes using a method called single cell RNA-Seq. This led to the discovery that after a heart attack, DNA from dying cells masquerades as a virus and activates an ancient antiviral program called the type I interferon response in specialized immune cells. The researchers named these “interferon inducible cells (IFNICs).”

When investigators blocked the interferon response, either genetically or with a neutralizing antibody given after the heart attack, there was less inflammation, less heart dysfunction, and improved survival. Specifically, blocking antiviral responses in mice improved survival from 60 percent to over 95 percent. These findings reveal a new potential therapeutic opportunity to prevent heart attacks from progressing to heart failure in patients.

“We are interested to learn whether interferons contribute to adverse cardiovascular outcomes after heart attacks in humans,” said King, who did most of the work on the study while he was a cardiology fellow at Brigham and Women’s Hospital and at the Center for Systems Biology at MGH in Boston.

The immune system has evolved innate antiviral programs to defend against a diverse range of invading pathogens. Immune cells do this by detecting molecular fingerprints of pathogens, activating a protein called IRF3, and secreting interferons, which orchestrate a defense program mediated by hundreds of interferon-stimulated genes. Investigators found that surprisingly, the antiviral interferon response is also turned on after a heart attack despite the absence of any infection. Their results point to dying cell DNA as the cause of this confusion because the immune system interprets it as the molecular signature of a virus.

Surprisingly, the immune cells participating in the interferon response were a previously unrecognized subset of cardiac macrophages. These cells could not be identified by conventional flow sorting because unique markers on the cell surface were not known. By using single cell RNA Seq, an emerging technique that combines microfluidic nanoliter droplet reactors with single cell barcoding and next generation sequencing, the researchers were able to examine expression of every gene in over 4,000 cardiac immune cells and found the specialized IFNIC population of responsible cells.

Future studies will aim to better understand the interferon response and the IFNIC cell type and explore their roles in the infarcted and remodeling heart. The team is also working to understand the interferon response in other tissues and diseases where cell death occurs.

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 Announces First Approval of Targeted Therapy Based on Basket Study

Precision medicine clinical trial leads to approval of first treatment for Erdheim-Chester disease

The US Food and Drug Administration (FDA) has announced that it has approved the drug vemurafenib for the treatment of patients with BRAF V600-mutant Erdheim-Chester disease (ECD). This is the first approval of a targeted therapy based on a basket study and the first-ever drug approved for ECD, a rare blood disorder.

This landmark approval came as a direct result of research at Memorial Sloan Kettering Cancer Center (MSK). MSK researchers, led by Physician-in-Chief José Baselga, MD, PhD, pioneered the concept of a basket study, which harnesses the power of precision medicine by assigning treatments to patients based on the genetic alterations driving their cancers rather than where their tumors originated in the body. This approval is based off of the data of 22 ECD patients enrolled in the phase II VE-BASKET study. 

ECD is one of an extremely rare form of blood cancers known collectively as histiocytoses that can lead to life-threatening complications, including damage to the heart, lungs, and kidneys. It’s estimated that there are fewer than 300 cases of ECD in the United States. More than 50 percent of people with ECD have BRAF V600-mutant disease, indicating that they would benefit from this drug. Previous treatments for ECD have included off-label use of chemotherapy, radiation, steroids, and the immunotherapy drug interferon, but all of these have limited efficacy based on anecdotal reports and potentially severe side effects.

Based on the work of MSK medical oncologist Paul Chapman, MD, vemurafenib was previously approved for the treatment of advanced melanoma that carries the BRAF V600E mutation. Dr. Chapman led the phase III trial for vemurafenib that led to the drug’s approval for that disease in 2011. In August 2017, vemurafenib was granted FDA Priority Review and Breakthrough Therapy Designation for the treatment of BRAF V600-mutant ECD.

About the Study

This approval is based on data from the phase II VE-BASKET study, a nonrandomized, histology-independent evaluation of the efficacy of vemurafenib, an inhibitor of BRAF V600 kinase, in non-melanoma cancers, including ECD. This first-in-kind study enrolled participants across multiple diseases, based predominantly on genetic profile rather than where the cancer originated. Initial study results were published in the New England Journal of Medicine in August 2015.

Final results for the 22 people with ECD showed a best overall response rate of 54.4 percent by RECIST v1.1. Importantly, responses and disease control were extremely durable. The median duration of response was not estimable at a median follow-up time of 26.6 months. At two years, 83 percent of patients remained progression free. The safety of vemurafenib in ECD patients was similar to that previously reported in patients with melanoma. The most common adverse events were joint pain, rash, hair loss, fatigue, change in heart rhythm and skin tags. 

Precision Medicine at MSK

Experts at MSK have taken the lead in developing clinical trials for a number of promising treatments that are based on tumors’ mutational profiles. Since August 2015, when MSK experts published initial results of the first basket study, histology-agnostic clinical trials have emerged as one important means of systematically testing a targeted therapy across a variety of tumor types. This innovative clinical trial design helps collect data faster and may accelerate the development of medicines for diseases with high unmet need. Basket studies can include many more people than disease-specific trials, allowing researchers to evaluate multiple diseases simultaneously. This is particularly important for diseases such as ECD that are extremely rare, making it difficult to fully enroll a disease or tumor-specific trial.

MSK leadership saw the promise of precision oncology early on and committed to realizing its ability to create better treatment options for all people with cancer. In 2014, the Marie-Josée and Henry R. Kravis Center for Molecular Oncology (CMO) was established to improve cancer care and research through genomic analysis and MSK-IMPACT™ (Integrated Mutation Profiling of Actionable Cancer Targets) was launched. This powerful diagnostic test provides detailed genetic information about a patient’s cancer that can guide treatment and identify clinical trial opportunities. To date, more than 20,000 MSK patients with advanced cancer have had their tumors sequenced through MSK-IMPACT. Most recently, Dr. Baselga and colleagues published a roadmap to precision oncology in the form of a seminal review paper in Cell.  

Breast cancer researchers track changes in normal mammary duct cells leading to disease

Breast cancer researchers have mapped early genetic alterations in normal-looking cells at various distances from primary tumours to show how changes along the lining of mammary ducts can lead to disease.

The findings of the multidisciplinary team of surgeons, pathologists and scientists led by principal investigator Dr. Susan Done are published online today in Nature Communications. Dr. Done, a pathologist affiliated with The Campbell Family Institute for Breast Cancer Research at Princess Margaret Cancer Centre, University Health Network, is also an associate professor in the Department of Laboratory Medicine and Pathobiology, University of Toronto.

“We have found another piece in the cancer puzzle – knowledge that could one day be used for more precision in screening and breast cancer prevention, and also help with therapeutic approaches to block some of the earliest alterations before cancer develops and starts to spread.”

Lead author Moustafa Abdalla writes: “Almost all genomic studies of breast cancer have focused on well-established tumours because it is technically challenging to study the earliest mutational events occurring in human breast epithelial cells.” Instead, this study found a way to identify early changes that preceded the tumour, enabling better understanding of cancer biology and disease development.

“Normal breast epithelium from the duct giving rise to a breast cancer has not been previously studied in this way.”

Dr. Done explains: “Most breast cancer starts in the epithelial cells lining the mammary ducts. But the breast ducts are complex structures, like the branches of a tree. Guesstimating which duct is close to the tumour is not very accurate. Thanks to our surgeons, we were able to obtain samples along normal-looking ducts close to the nipple and close to the tumour, as well as samples on the opposite side of the same breast to study and compare.”

In the operating room, surgeons inserted a fibre-optic scope through the nipple into the ducts below, and then injected dye into cancerous breasts being removed. This ductoscopy technique enabled the pathologists to identify the exact duct leading to the tumour and subsequently classify genetic alterations either increasing or decreasing as they moved nearer to the cancer.

“Cancer is not a switch that happens overnight. Once a patient notices a lump the tumour has been present for some time accumulating genetic changes. It is difficult at that point to identify the first changes that may have had a role in initiating or starting the cancer,” says Dr. Done.

The research further identified genes that seem to be acting together in groups or pathways. “Some of these genes were either increased or decreased in the area of the tumour, no matter the type of breast cancer, and this is important because within the patterns we identified were predictable alterations. This meant we could determine from the sample where it came from in the breast,” says Dr. Done.

“Our research demonstrated and supports earlier research from elsewhere that changes in cells occur before you can see them. The fact that changes are already present in different regions of the breast could be important in the delivery of radiation therapy or surgical margin assessment. We’re a long way from bringing this into clinic, but it is something we will think about as we continue our research.”

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.

Cancer trial led by University of Minnesota Medical School’s Dr. Clark Chen shows promise

New data from a Phase I clinical trial led by Clark Chen, M.D., Ph.D., Lyle French Chair in Neurosurgery and Head of the University of Minnesota Medical School Department of Neurosurgery shows more than a quarter of patients with recurrent high-grade glioma, a form of brain cancer, were alive more than three years after treatment.

“Given the deadly nature of this disease, three-year survival is rarely reported in the recurrent setting. It is notable that the survival benefit was seen across a range of patients and not just limited to patients with specific genetic mutations,” said Chen. “This finding indicates that many patients could benefit from this treatment.”

As Chen explained at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics two steps were involved in the treatment of the 56 patients who participated in this clinical trial. First, patients were injected with Toca 511, which is a replicating virus that only infects actively dividing tumor cells. Once inside the cancer cell, the virus delivered a gene for an enzyme, cytosine deaminase (CD). As the virus began to replicate and spread to other cancer cells, it programmed them to make CD. Next, patients received a pill, Toca FC, which is an inert compound. Once inside the cancer cell, CD converted Toca FC into the anticancer drug 5-fluorouracil, which killed the cancer cell. In addition to destroying the cancer cells, 5-fluorouracil killed certain immune suppressive myeloid cells, thus boosting the patient’s immune system to recognize and attack the cancer cells.

“The treatment we tested in this trial delivers local chemotherapy specifically to the brain tumor. Toca 511 and Toca FC work together to turn the brain tumor into a factory that produces an anticancer drug while also activating the immune system through a combination of mechanisms, which together work to attack the cancer,” Chen said.

Dr. Chen also noted that five patients are experiencing a durable complete response with a median of at least 35.7 months. Within a subgroup of 23 patients, there were an additional five patients who achieved stable disease, bringing the number of patients who derived benefit from Toca 511 to 10 (or 43.4 percent of the patients who underwent Toca 511 therapy).

According to Chen, the median survival in this trial is nearly double that of historical data. In the subgroup, median survival was 14.4 months, compared to approximately eight months for historical controls.

“Brain cancer is one of the deadliest cancers, giving urgency to finding an effective treatment,” Chen said. “The 160,000 people diagnosed with high-grade gliomas worldwide each year–and high-profile cases including U.S. Senator John McCain, Senator Edward Kennedy, and Beau Biden–demonstrate the high unmet need of this disease. The data generated in the Toca 511 research provides hope for patients with brain cancer and their families.”

This study was a single arm trial without a control group which acted as a limitation. “The ongoing randomized phase II/III trial will be important to confirm the promising safety and efficacy results reported in this Phase I study,” Chen noted.

Public-Private Consortium Aims to Cut Preclinical Cancer Drug Discovery from Six Years to Just One

Scientists from two U.S. national laboratories, industry and academia today launched an unprecedented effort to transform the way cancer drugs are discovered by creating an open and sharable platform that integrates high-performance computing, shared biological data from public and industry sources and emerging biotechnologies to dramatically accelerate the discovery of effective cancer therapies.

The goal of the consortium – Accelerating Therapeutics for Opportunities in Medicine (ATOM) – is to create a new paradigm of drug discovery that would reduce the time from an identified drug target to clinical candidate from the current approximately six years to just 12 months. ATOM aims to transform cancer drug discovery from a time-consuming, sequential and high-risk process into an approach that is rapid, integrated and with better patient outcomes — using supercomputers to pretest many molecules simultaneously for safety and efficacy.

The consortium comprises the Department of Energy’s Lawrence Livermore National Laboratory (LLNL), GSK, the National Cancer Institute’s Frederick National Laboratory for Cancer Research (FNLCR), and the University of California, San Francisco (UCSF). ATOM welcomes additional public and private partners who share the vision.

“The goals of ATOM are tightly aligned with those of the 21st Century Cures Act, which aims in part to enable a greater number of therapies to reach more patients more quickly,” said FNLCR Laboratory Director David Heimbrook. “Although initially focused on precision oncology – treatments targeted specifically to the characteristics of the individual patient’s cancer – the consortium’s discoveries could accelerate drug discovery against many diseases.”

ATOM will develop, test and validate a multidisciplinary approach to drug discovery in which modern science, technology and engineering, supercomputing simulations, data science and artificial intelligence are highly integrated into a single drug-discovery platform that can untimately be shared with the drug development community at large.

“As we have learned more about what modern supercomputers can do, we’ve gained confidence that this approach can make a big difference in creating medicines,” said John Baldoni, senior vice president, R&D at GSK. “We must do all that we can to reduce the time it takes to get medicines to patients. GSK is working to set a precedent with pharmaceutical companies by sharing data on failed compounds.”

GSK will initially contribute chemical and in vitro biological data for more than 2 million compounds from its historic and current screening collection, as well as preclinical and clinical information on 500 molecules that have failed in development but could help accelerate development of new compounds by providing knowledge about the underlying biology of candidate compounds and that of the human body. Combined with data on successful drugs, GSK’s offering represents a broad base of information for ATOM researchers. In addition, GSK will provide expertise in drug discovery and development, computational chemistry and biology.

The ATOM team will combine data provided by GSK with publicly available data, and that of future consortium members, to generate new dynamic models that can better predict how molecules will behave in the body compared to the current iterative and time-consuming practices. In this effort, LLNL will contribute its best-in-class supercomputers, including its next-generation system Sierra, as well as its expertise and innovative approaches to modeling and simulation, cognitive computing, machine learning and algorithm development. More broadly, by tackling the ambitious challenge of cancer therapies, ATOM will drive technologies vital to the core missions of the Department of Energy and National Nuclear Security Administration (NNSA).

“ATOM is a novel public-private partnership that draws on the lab’s unique capabilities to create a paradigm change in drug development,” said LLNL Director Bill Goldstein. “It will help to strengthen U.S. leadership in high-performance computing and, by speeding the discovery of therapeutics, contribute to biosecurity.”

For its part, FNLCR will contribute from its wealth of scientific expertise in precision oncology, computational chemistry and cancer biology, as well as support for open sharing of data sets and predictive modeling and simulation tools. UCSF will provide expertise from a long history of innovation in drug discovery and medicine to improve the lives of patients.

“We at UCSF are eager to lend our expertise to this effort,” said UCSF Chancellor Sam Hawgood, MBBS. “UCSF scientists and clinicians have long been leaders in drug discovery, therapeutics, and cancer biology with the UCSF Helen Diller Family Comprehensive Care Center among the top-ranked cancer institutes in the country. Our role with ATOM is therefore in lock step with UCSF’s mission of advancing health worldwide.”

ATOM welcomes additional public and private partners who share the vision of the consortium, which will have physical headquarters in the Mission Bay neighborhood of San Francisco, adjacent to UCSF’s newest campus.

Vanderbilt-Ingram Cancer Center Patients Treated with New FDA-Approved CAR T Therapy

Vanderbilt-Ingram Cancer Center (VICC) has been selected as one of the few authorized treatment centers in the United States approved to administer the first FDA- approved chimeric antigen receptor T cell (CAR T) therapy for treatment of adult patients with a specific type of lymphoma. VICC is the only cancer center in a seven-state region of the Southeast authorized to deliver the new immunotherapy.

On Oct. 18, Kite, a Gilead Company, received FDA approval for its CAR T therapy Yescarta™ (axicabtagene ciloleucel), a breakthrough in hematologic cancer treatment in which a patient’s own immune system T cells are engineered to seek and destroy cancer cells. CAR T therapy is manufactured specifically for each individual patient.

VICC has been administering Kite’s CAR T therapy to adult patients participating in the ZUMA-1 clinical trial.

“We are honored to be selected as one of the first cancer centers in the U.S. approved to administer this groundbreaking immunotherapy to our patients,” said Madan Jagasia, MBBS, M.S., co-leader of the Translational Research and Interventional Oncology Research Program, section chief of Hematology and Stem Cell Transplant, and director of the Outpatient Transplant Program at VICC. “We have a team of experienced clinicians who have specialized knowledge about how to manage care for these patients while they undergo this novel therapy.”

Yescarta is approved for the treatment of adults whose cancer has recurred following at least two other forms of treatment. Specific types include large B-cell lymphoma (DLBCL), primary mediastinal large B-cell lymphoma (PMBCL), high-grade B-cell lymphoma, and DLBCL arising from follicular lymphoma (transformed follicular lymphoma, or TFL).

Diffuse large B-cell lymphoma is the most common aggressive non-Hodgkin lymphoma (NHL). While chemotherapy or stem cell transplant is effective for some patients, the cancer often recurs, and with the current standard of care those patients often have a median overall survival of about six months. Now those patients have another treatment option.

In the ZUMA-1 study, 72 percent of patients treated with a single infusion of Yescarta responded to therapy (overall response rate) including 51 percent of patients who had no detectable cancer remaining (complete remission).

VICC’s first clinical trial patients were treated with Yescarta nearly two years ago and nearly all of them remain in remission from their disease.

Olalekan Oluwole, MBBS, MPH, assistant professor of Medicine, led the clinical trial for VICC.

“I think it is safe to say that these new CAR T therapies will become part of what we do on a day-to-day basis to treat lymphoma. They have clearly made opportunities available for people who normally would have few viable options. Because of the way this new immunotherapy works, this technology has actually moved the field further towards eradicating cancer,” said Oluwole.

Donald Pender, 67, a retired GM auto worker from Spring Hill, Tennessee, was the second patient treated at VICC. He had already been treated with chemotherapy and a stem cell transplant, but his non-Hodgkin lymphoma came back and he decided to take part in the clinical trial for the new CAR T therapy.

“They knew this worked but didn’t know if it would work for me. I wanted to give it a try. I thought I don’t have anything else to lose, let’s go for it,” said Pender.

His cancer is now in remission and he is grateful that the clinicians at VICC offered him the chance to participate in the trial.

“It’s a special place, it really is. If there’s something going on in medicine, they’re doing it,” said Pender.

Because there are potential severe complications involved with this type of therapy, all treatment sites like VICC must have special certification acknowledging that the center is able to handle these risks. The most severe and potentially life-threatening side effects include high fevers, low blood pressure and brain swelling that may require care in the intensive care unit.

“As part of the national team testing this new CAR T therapy, we have developed specific protocols to manage these patients,” said Jagasia. “VICC has a group of highly experienced physicians who work closely with subspecialty care teams and we have immediate access to the intensive care unit.”

This is the second CAR T immunotherapy that will be available to Vanderbilt patients. Monroe Carell Jr. Children’s Hospital at Vanderbilt is part of a select group of health care institutions recently chosen to offer a new FDA-approved immunotherapy for a subset of pediatric acute lymphoblastic leukemia (ALL) patients. Kymriah, which is manufactured by Novartis, was the first gene therapy approved by the FDA.

Proton therapy for prostate cancer is advantageous to imrt according to new study

Proton therapy treatment for prostate cancer is associated with higher survival rates and decreased risk of complications compared to intensity-modulated radiation therapy (IMRT) according to a new study by researchers at the Northwestern Medicine Chicago Proton Center. The study is being presented at the 4th Annual Particle Therapy Co-Operative Group North-America (PTCOG-NA) Conference on October 25 in Chicago.

“This new evidence supports that proton therapy is at least as good as standard radiation therapy and may be significantly better in some areas, especially protecting normal tissue outside of the prostate,” said the study’s lead author William Hartsell, MD, medical director of the Northwestern Medicine Chicago Proton Center. “In addition, the evidence shows that proton therapy is advantageous for younger patients who we are most concerned about developing secondary cancers later in life.”

Proton therapy uses protons – heavy, positively charged atomic particles – instead of the standard X-rays used in conventional radiation therapy. Protons deposit much of their energy, or dose, directly in the tumor and then stop, whereas conventional radiation continues to deposit the dose beyond the tumor.

Dr. Hartsell and colleagues reviewed the records of over 28,000 IMRT patients and 851 proton patients who received treatment from 2006-2012, using the Medicare and SEER (Surveillance, Epidemiology and End-Results Reporting) national databases. The proton patients were matched to IMRT patients in a 1:5 matching process using several parameters, including comorbidity index, cancer stage, tumor grade, adjuvant chemo/hormone therapy, age, zip code and ethnicity.

Using the matched patient cohort, the 5-year overall survival rate for proton therapy was 93.25% compared to 88.43% for IMRT. For the matched group of intermediate risk patients, the gap was slightly greater with a 5-year overall survival for proton therapy patients of 93.65% compared to 88.27% for IMRT.

The study also reviewed the incidence of complications and found significantly more patients with bladder, endocrine or “other” complications with IMRT compared to protons. In addition, there were greater numbers of patients with secondary malignancies with IMRT. 10.5% for IMRT compared to 6.1% for proton therapy at 5 years.

“This study is a significant update on the efficacy of proton therapy for prostate cancer. Many insurance companies are relying on outdated and incorrect data to determine coverage,” said Dr. Hartsell.

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.

Intermountain Healthcare Researchers Launch Major Three-Year Genomics Breast Cancer Study

Cancer researchers at Intermountain Medical Center and the Intermountain Healthcare Precision Genomics Program in Salt Lake City are launching a three-year study to determine if a blood test that looks for DNA from a cancer tumor can be used to complement mammography to improve the way breast cancer is diagnosed.

The goal of this new genomics study is to show whether screening patients for the presence of circulating tumor DNA, known as ctDNA, can successfully detect breast cancer using a blood draw.

Breast cancer is the second-leading cause of cancer deaths in women, behind only lung cancer, with an estimated 40,610 deaths each year from the disease. Nearly 253,000 new cases of invasive breast cancer are diagnosed each year, along with about 60,000 non-invasive, early-stage cases, according to the American Cancer Society.

The Intermountain study is unique in that researchers will also help develop a specific test to check for ctDNA, and will have access to both mammography results and the DNA blood test results, which will allow a direct comparison of the “liquid-based biopsy” to be made.

The idea behind the science is simple, though researchers say the execution is not yet proven: Little pieces of DNA that come from dying cells end up in the peripheral blood stream, including circulating tumor cells. The goal of researchers is to use those markers to identify breast cancer, perhaps even before mammography can detect it, said Lincoln Nadauld, MD, PhD, co-lead investigator of the study and executive director of the Intermountain Healthcare Precision Genomics Program.

“As a tumor is growing, some of the cells will die and their DNA will end up in the peripheral blood stream,” Dr. Nadauld said. “We’re able to distinguish DNA from cancer vs. DNA from normal cells. The idea is to leverage DNA to see if we can detect that it comes from a tumor.”

In the study, patients with known breast cancer will be compared with those in a screening group.

“We don’t know what we’ll see yet,” said Brett Parkinson, MD, co-lead investigator of the study, who is also imaging director and medical director of the Intermountain Medical Center Breast Care Center in Murray. “We might find those who have breast cancer will have a negative blood test and learn it’s not a good screening tool.”

Even a successful blood test isn’t expected to replace mammography outright. If it detects the circulating tumor DNA, imaging would be needed to find the tumor. But it could help eliminate unneeded biopsies, Dr. Parkinson added.

Dr. Nadauld said cancers have mutations in their DNA that aren’t always unique.

“Sometimes those are the same whether it’s a breast cancer or a colon cancer. If we do create a blood test, it’s possible it would detect mutant DNA, but it might look so similar it would be hard to tell what kind of cancer it came from,” he said. “That’s part of what this trial is going to accomplish. We want to determine the signature for early breast cancer.”

If successful, a liquid biopsy might also be used to monitor a breast cancer survivor for recurrence, Dr. Nadauld said. It might even lead to development of similar tests for different types of cancer. But that would be a challenge for the future.

“We want to approach this with laser-like focus,” he said. “It’s needed to help us diagnose breast cancer. We need to detect it earlier, when it’s curable.”

Breast cancer survival depends largely on finding the disease early —and mammography is the only screening exam that’s been shown by multiple randomized clinical trials to reduce the mortality rate for breast cancer. Since 1991, the death rate from breast cancer is down 38 percent, largely because mammography screening tests lead to early detection.

Although mammography finds most breast cancers, it may not detect malignancy in women who have dense breast tissue, especially premenopausal women, or those under 50.

“We pick up most breast cancer in women with average breast density,” said Dr. Parkinson. “When breast tissue is denser, we can miss up to 30 percent of breast cancers.”

Mammography also has a false-positive or call-back rate of 10 percent, which may subject women to additional imaging and emotional duress. Plus, a mammogram can be uncomfortable, since breast tissue is compressed for imaging, which also exposes a woman to a small amount of radiation. Mammography may also be inconvenient, often requiring women to take time off work, he noted.

For those, and perhaps other reasons, mammography screening rates in the United States are low. In Utah, only about 65 percent of eligible women are screened, despite Intermountain Healthcare’s recommendations that women over 40 undergo yearly screening mammography. All major medical and advocacy organizations agree that screening every year after a woman is 40 saves more lives. About 20 percent of breast cancers occur in women under 50.

Dr. Nadauld said the unusual confluence of three factors weigh in Intermountain’s favor on this quest, starting with access to a lot of patients in one place who are getting mammograms, which are the gold standard screening test for breast cancer. Second, the researchers have access to the results of those mammograms; they know if the results were positive or negative. The third major factor is Intermountain’s genomic technology capability.

“This is the big conversation right now in all of oncology — the use of liquid biopsy to determine how to screen for breast cancer, a woman’s risk of recurrence, and how to monitor their treatment,” Dr. Nadauld said.

The study is being made possible by a generous donation from the Beesley Family Foundation.

Moffitt Researchers Discover New Targets for Approved Cancer Drug

New study shows ALK inhibitor ceritinib may have the ability to be used for more than ALK-rearranged non-small cell lung cancer

Developing new drugs to treat cancer can be a painstaking process taking over a decade from start to Food and Drug Administration approval. Scientists are trying to develop innovative strategies to identify and test new drugs quicker and more efficiently. A team of researchers at Moffitt Cancer Center used cellular drug screening, functional proteomics and computer-based modeling to determine whether drugs with well-known targets may be repurposed for use against other biological targets. They found that an FDA approved drug for non-small cell lung cancer called ceritinib has anti-cancer activity against previously unknown targets. Their results were published today in the journal, Nature Chemical Biology.

For the past 20 years, there has been an emphasis on targeted cancer therapy – targeting a specific driver of cancer development to minimize side effects typically seen with chemotherapy. This personalized approach has been successful in certain types of cancer that are primarily driven by a single DNA alteration, such as found in chronic myeloid leukemia. However, the majority of cancers are not caused by a single mutation; rather, cancer is more commonly caused by a large network of mutations and alterations. Some researchers, including those from Moffitt, are beginning to rethink the targeted approach to cancer therapy. They believe that developing drugs that act on multiple targets, called a polypharmacology approach, may more effectively treat those cancers that have a network of alterations.

In order to identify drugs that act on multiple targets, Moffitt researchers screened 240 drugs that are either FDA approved or in clinical development. They noticed that the drug ceritinib acts differently than other drugs in its class. Ceritinib targets a protein called ALK, and is approved to treat patients with ALK-rearranged metastatic non-small cell lung cancer. Their research found that ceritinib also inhibits the growth of lung cancer cells that do not have genetic alterations in the ALK gene.

After an extensive set of experiments to learn how ceritinib worked in cells without ALK rearrangements, they discovered the drug inhibits several other previously unknown targets, and that these signals converge onto a protein known to be responsible for causing drug resistance to paclitaxel. Importantly, the researchers showed that ceritinib combined with paclitaxel was more effective than either agent alone at reducing cell viability.

These findings suggest that ceritinib together with paclitaxel may be effective against other cancers that do not have ALK rearrangements, and that this drug combination may be used to target a network of changes in cancer.

“The results also demonstrate the benefits of using a combined screening, proteomics and computer-based modeling approach to identify drugs that act on multiple targets and to determine how they function,” said study lead author Uwe Rix, Ph.D., assistant member of the Drug Discovery Program at Moffitt. “In the future, this strategy may facilitate further drug repurposing efforts and lead to an increase in new therapy options for patients with difficult-to-treat diseases.”

Bariatric surgery lowers cancer risk for severely obese patients

Severely obese patients who undergo bariatric surgery lower their risk of developing cancer by at least a third, according to a University of Cincinnati (UC) College of Medicine researcher leading a large retrospective cohort study of patients in the western United States.

“We found having bariatric surgery is associated with a reduced risk of cancer, especially obesity-associated cancers including postmenopausal breast cancer, endometrial cancer, pancreatic cancer and colon cancer,” explains Daniel Schauer, MD, associate professor in the UC Division of General Internal Medicine and lead researcher. “What’s surprising is how great the risk of cancer was reduced.”

The findings were recently published online in the Annals of Surgery.

The study reviewed medical data of 22,198 individuals who had bariatric surgery and 66,427 nonsurgical patients between 2005 and 2012 with follow-up through 2014. It pulled data from large integrated health insurance and health care delivery systems from five study sites operated by Kaiser Permanente–Southern California, Northern California, Oregon, Colorado and Washington.

More than 80 percent of patients in the study were women.

Patients undergoing bariatric surgery had a 33 percent lower risk of developing any cancer during follow-up, according to the published findings. Schauer says the benefit is greatest among obesity-associated cancers. The risk of postmenopausal breast cancer dropped by 42 percent and while the risk for endometrial cancer dropped 50 percent in severely obese patients. The risk of colon cancer dropped 41 percent while the risk of pancreatic cancer was lowered by 54 percent.

“Cancer risks for postmenopausal breast cancer and endometrial cancer are closely related to estrogen levels,” says Schauer. “Having weight loss surgery reduces estrogen level.”

Bariatric surgery helps reduce the risk of diabetes and insulin levels which may be a risk factor for pancreatic cancer, while the mechanisms for colon cancer are more complicated, says Schauer.

“I think considering cancer risk is one small piece of the puzzle when considering bariatric surgery, but there are many factors to consider. Reductions in diabetes, hypertension and improvements in survival and quality of life are reason enough,” says Schauer. “The study provides an additional reason to consider bariatric surgery.”

The study found no significant association between bariatric surgery and cancer risk among men. Schauer says that may be because the vast majority of study patients are female and at least two of the cancers most impacted by bariatric surgery, postmenopausal breast cancer and endometrial cancer, affect women only.

Multivariable Cox proportional-hazards models were used to examine the incidence of cancer up to 10 years after bariatric surgery compared to the matched nonsurgical patients. After a mean follow-up of 3.5 years, researchers identified 2,543 incident cancers.

About 15 million adults in the United States suffer from severe obesity, which is defined as having a body mass index of greater than 35 kg/m2. Obesity and cancer are closely linked. Obesity is associated with up to 40 percent of all cancers diagnosed in the United States, says Schauer.

Tests with topical treatment strategy for fighting skin cancer yield positive results

Researchers at the University of São Paulo (USP), in Brazil, are testing a technique in mice that combines low-intensity electric current with a formulation containing nanoencapsulated chemotherapy to treat skin cancer.

Applying a low-intensity unidirectional current is one of the ways to ensure that chemical substances penetrate the skin, pushed into the bloodstream through the electric field using a technique known as iontophoresis.

According to preliminary results of the study, cancer-induced mice which received the formulation combined with iontophoresis presented a significantly greater reduction in the size of the tumor than those that received it through injection.

“One of the challenges involved in this type of topical treatment is ensuring that the drug penetrates the stratum corneum – the outermost layer of the epidermis, composed mainly of dead cells. It is an important tissue barrier against the entry of microorganisms, but it also makes it more difficult for medicines to penetrate,” explained Renata Fonseca Vianna Lopez, who supervises the Thematic Project supported by the São Paulo Research Foundation – FAPESP and is also a at the School of Pharmaceutical Sciences of Ribeirão Preto (FCFRP-USP).

In the case of skin cancer, however, the intent is not that the drug penetrates the tissue to get into the bloodstream, but rather that it becomes concentrated in the area below the stratum corneum that requires treatment. This is the reason why, in the study led by Lopez, she chose to place the chemotherapeutic agent inside nanoparticles.

In vivo tests

Using mice, the researchers induced the formation of a tumor associated with one of the most common types of skin cancer – squamous cell carcinoma – through a subcutaneous injection of human tumor cells that overexpress the epidermal growth factor receptor (EGFR). Lopez explained that the presence of this protein causes the tumor to become more aggressive.

The treatment was conducted using a formulation containing chemotherapy agent 5-fluorouracil encapsulated in a nanoparticle (liposome) that functions as an anti-EGFR antibody. The malignant cells are able to capture a larger quantity of the drug encapsulated in these liposomes.

One group of rodents received the tumor formulation through subcutaneous injections and another group received it through topical application combined with iontophoresis. Lopez compared both methods and thus assessed:

“In addition to reducing the size of the tumor, the topical treatment left the tumor less aggressive. We believe that this method combined with iontophoresis allows the drug to be dispersed over the entire area of the tumor, whereas the subcutaneous application causes it to be concentrated in a single location,” Lopez noted.

Versatile technique

In another study, Lopez’ group used a stiffer type of polymeric nanoparticle, one containing the anti-inflammatory dexamethasone associated with iontophoresis for the treatment of uveitis – an inflammation of the eye tissue. The results, published in 2015 in the Journal of Controlled Release, is the outcome of the doctoral thesis of Joel Gonçalves Souza, winner of the 2015 Capes Thesis Award in Pharmacy.

“When we apply the medicine directly to the eye, it is quickly eliminated through the defense mechanisms, such as tears. Increased penetration and better results are obtained by using the application method combined with iontophoresis,” Lopez said.

Currently, in dissertation research by Camila Lemos, the group plans to test a method that uses iontophoresis in the treatment of chronic wounds such as those that develop in patients with diabetes.

“In this case, we are not dealing with the stratum corneum barrier. We use iontophoresis to assess its influence on release of the substance of interest in a formulation, and to investigate its effect on the growth of microorganisms,” Lopez explained.

The strategy consists of placing a peptide having anti-inflammatory properties on a film made of fibers extracted from the cocoon of a silkworm (fibroin). The film is placed on the wound as a dressing, to which an electric current is then applied.

“When we placed the peptide directly on the wound, it degraded very quickly. When placed on the film, however, release occurs in a slower and more sustained way. Iontophoresis allows a larger amount of the peptide to be released from the film at the start of treatment to accelerate healing,” the researcher explained.

Lopez went on to say that preliminary results suggest that iontophoresis also stops the proliferation of some types of microorganisms (particularly gram-positive bacteria) that could aggravate wounds.

KEYNOTE-040 evaluates pembrolizumab in head and neck cancer

Immunotherapy with the checkpoint inhibitor pembrolizumab may be a better option than standard treatments for patients whose head and neck cancer has spread, or recurred after an initial round of chemotherapy, according to results of the Keynote-040 trial presented at the ESMO 2017 Congress in Madrid. (1)

Although the 19% improvement in overall survival among patients treated with pembrolizumab did not meet the prespecified difference for statistical significance, it was nevertheless a clinically meaningful difference for this population who only lived seven to eight months, on average, after initiating treatment, said lead investigator Dr. Ezra Cohen, from the University of California, San Diego Moores Cancer Center, in La Jolla, California.

“Even though the study did not meet its primary endpoint, I still think it is a positive trial,” he said. “It reinforces that pembrolizumab should continue to be offered as an important option for all patients with this devastating disease.”

The KEYNOTE-040 trial was a global, open-label, phase 3 study which included patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) after a platinum-based chemotherapy.

Patients were randomised to receive either pembrolizumab (n=247) or standard of care (SOC) treatment (n=248), which was the investigator’s choice of either methotrexate, docetaxel, or cetuximab.

Median overall survival (OS) was only marginally higher in the pembrolizumab compared to standard treatment arm (8.4 versus 7.1 months, hazard ratio [HR] 0.81 95% CI 0.66-0.99, P= .0204), however for a subset of patients who had PD-L1-expressing tumours, pembrolizumab was associated with dramatic and significantly improved outcomes.

Specifically, among patients with combined tumour and immune cell PD-L1-expression (CPS) of at least 1%, median OS was 8.7 months with pembrolizumab versus 7.1 months with standard treatments (HR 0.75; 95% CI 0.59-0.95, P=.0078), and among patients with PD-L1-expression in more than 50% of their cancer cells, median OS was 11.6 versus 7.9 months respectively (HR 0.54; 95% CI 0.35-0.82, P=.0017).

Compared to the other treatments, pembrolizumab measured up well in terms of side-effects.

“In almost every category it had a better side-effect profile, meaning a lower incidence of toxicity, versus standard treatments,” said Cohen. “The exception is hypothrodism, which occurred in 13% of those treated with pembro versus only 1% of those given other treatments.”

Overall, Cohen said the KEYNOTE-040 trial reinforces what is already known about anti-PD therapy in head and neck cancer. “From a clinician’s perspective I would feel the same in any country. This is a meaningful therapy that improves survival.”

Asked to comment for ESMO, Dr. Amanda Psyrri, from the University of Athens Medical School, and Attikon University Hospital in Athens said: “Keynote-040 did not reach its primary endpoint of overall survival; however, pembrolizumab was superior to investigator’s choice in terms of toxicity, an important consideration in treatment decisions for these poor-prognosis patients with recurrent/metastatic platinum-refractory HNSCC. As the authors point out, subsequent immunotherapy in the SOC arm may have confounded OS analysis. The magnitude of treatment effect was greater in patients with PD-L1 combined positive score (CPS) ? 1%, especially those with CPS ?50%,suggesting that pembrolizumab may represent the preferable treatment option for this subset of patients.”