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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.”

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Cancer Immunotherapy May Get a Boost by Disabling Specific T Cells

Cancer immunotherapy drugs only work for a minority of patients, but a generic drug now used to increase blood flow may be able to improve those odds, a study by Columbia University Medical Center (CUMC) researchers suggests.

In mice with melanoma, the researchers found that the drug – called pentoxifylline – boosts the effectiveness of immune-checkpoint inhibitors, a type of immunotherapy now commonly used in the treatment of melanoma and other cancers.

The study was published today in the online edition of Cell.

Checkpoint-blockade immunotherapy drugs – the first drugs were approved in 2011 – target proteins on tumor cells or cells of the immune system that prevent “killer” T cells from attacking cancer. These drugs have revolutionized cancer care, but do not work for all patients. “In advanced melanoma, for example, the cure rate is only about 20 percent. That’s a remarkable improvement over previous therapies,” says study leader Sankar Ghosh, PhD, Chair and Silverstein and Hutt Family Professor of Microbiology & Immunology. “But why doesn’t it work for the other 80 percent? There must be another mechanism that contributes to the suppression of the immune response.”

Dr. Ghosh and other cancer biologists suspected that a different type of T cell, known as regulatory T cells, or Tregs, may also suppress the immune system’s attack on cancer. Large numbers of these cells are found within several types of tumors. “One possible therapy would be to get rid of Tregs,” he said. “But Tregs are also needed to keep the immune system in check, and shutting down Tregs completely would unleash an attack against the body’s healthy cells and organs.”

This point is underscored by a related study, published today in Immunity, in which Dr. Ghosh and colleagues found that removing NF-kB from Tregs caused widespread and lethal autoimmunity in mice. However, a partial inhibition of NF-kB, achieved by removing only one, specific, NF-kB protein, called c-Rel, changed Treg function without causing widespread autoimmunity.  In the Cell study Ghosh and colleagues showed that these c-Rel deficient Tregs were specifically crippled in their ability to protect cancer cells. As a result, when c-Rel is blocked, killer T cells mounted a more robust attack on cancer cells without causing autoimmunity.

Pentoxifylline is a drug that is used in patients to increase blood flow in the hands and feet of people with poor circulation, but it’s also known to inhibit the c-Rel protein. In the Cell study, the researchers demonstrated that pentoxifylline blocked Treg function and boosted the effectiveness of standard checkpoint-blockade immunotherapies.  As a result, mice treated with both drugs showed significantly reduced melanoma tumor burden, compared to animals that received the standard therapy alone.

“The next step is to test this drug combination in human clinical trials,” Dr. Ghosh says. “If trials are successful, the use of c-Rel inhibitors could become a standard addition to immune checkpoint therapy for many types of cancer.”

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Immune cells may be key to better allergy, infection therapies

By learning how a recently discovered immune cell works in the body, researchers hope to one day harness the cells to better treat allergies and infections, according to new Cornell University research.

Type 1 regulatory (Tr1) cells are a type of regulatory immune cell that help suppress immune responses, including inflammation and tissue damage, but very few details were known about their development and function.

A new study with mice and humans, published in the journal Nature Communications, describes how an enzyme called ITK plays a crucial role in the development of Tr1 cells during an immune response. The enzyme offers an entry point for researchers to manipulate the development of Tr1 cells to enhance them to treat allergies, for instance, or block their development to treat viral and bacterial infections.

“The more we understand about how these cells develop, the signals and pathways they use, the more likely we’ll be able to devise approaches to manipulate them,” said Avery August, professor of microbiology and immunology in Cornell’s College of Veterinary Medicine and the paper’s senior author. Weishan Huang, assistant research professor of microbiology and immunology, is lead author.

Doctors employ antigen immunotherapy to treat allergies by administering a regimen that exposes a patient to increasing doses of an allergen over a period of months. Since allergies are caused by an overactive immune response to an allergen, the treatment works because Tr1 cells help suppress the immune system and lower inflammation. In the future, clinicians may want to enhance the pathway to produce more Tr1 cells, August said.

But when treating viral infections such as the flu, bacterial infections and tumors, clinicians may want to selectively block the pathway to lower the number of Tr1 cells. In experiments with mice, August and colleagues found that Tr1 cells increase when a mouse is infected with viruses or bacteria or when fighting tumors. By tempering the development of Tr1 cells, and carefully reducing their activity to suppress the immune response, patients may recover faster from certain diseases.

“This is a balance because these cells are there for a purpose, and we think their purpose is to make sure the immune system doesn’t destroy and cause pathology in an immune response,” August said.

The danger with flu, for example, is that at a certain point other types of immune system T cells, whose purpose is to kill infected cells, start to destroy tissue. In such cases, an overactive immune response can lead to death.

“We’d have to do experiments to find out whether we can tune the function of Tr1 cells,” August said, “so we balance the beneficial aspects of the immune response with the damaging aspects of the immune response.”

In the study, August, Huang and their colleagues bred genetically altered mice so they carried a gene that makes Tr1 cells glow green when they develop, which allows for easy tracking. They then bred another type of mouse that had fluorescent Tr1 cells and also allowed the researchers to specifically block the enzymatic activity of ITK. Using the same protocol, they created a third type of mouse that lacked ITK.

In both the mice where ITK was inhibited and the mice that lacked ITK, Tr1 cells failed to develop. Using blood cells from anonymous human volunteers, they got the same results.

In a second experiment, the researchers identified a second critical enzyme in the pathway that leads to the development of Tr1 cells. This other enzyme, called IRF4, is a transcription factor that regulates the expression of a number of genes and proved key for controlling whether Tr1 cells developed. The team also confirmed that the same pathway exists in people.

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Scientists create stem cell therapy for lung fibrosis conditions

A team of scientists from the UNC School of Medicine and North Carolina State University (NCSU) has developed promising research towards a possible stem cell treatment for several lung conditions, such as idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), and cystic fibrosis — often-fatal conditions that affect tens of millions of Americans.

In the journal Respiratory Research, the scientists demonstrated that they could harvest lung stem cells from people using a relatively non-invasive, doctor’s-office technique. They were then able to multiply the harvested lung cells in the lab to yield enough cells sufficient for human therapy.

In a second study, published in the journal Stem Cells Translational Medicine, the team showed that in rodents they could use the same type of lung cell to successfully treat a model of IPF – a chronic, irreversible, and ultimately fatal disease characterized by a progressive decline in lung function.

The researchers have been in discussions with the FDA and are preparing an application for an initial clinical trial in patients with IPF.

“This is the first time anyone has generated potentially therapeutic lung stem cells from minimally invasive biopsy specimens,” said co-senior author of both papers Jason Lobo, MD, an assistant professor of medicine at UNC and medical director of lung transplant and interstitial lung disease.

Co-senior author Ke Cheng, PhD, an associate professor in NCSU’s Department of Molecular Biomedical Sciences and the UNC/NCSU Joint Department of Biomedical Engineering, said, “We think the properties of these cells make them potentially therapeutic for a wide range of lung fibrosis diseases.”

These diseases of the lung involve the buildup of fibrous, scar-like tissue, typically due to chronic lung inflammation. As this fibrous tissue replaces working lung tissue, the lungs become less able to transfer oxygen to the blood. Patients ultimately are at risk of early death from respiratory failure. In the case of IPF, which has been linked to smoking, most patients live for fewer than five years after diagnosis.

The two FDA-approved drug treatments for IPF reduce symptoms but do not stop the underlying disease process. The only effective treatment is a lung transplant, which carries a high mortality risk and involves the long-term use of immunosuppressive drugs.

Scientists have been studying the alternative possibility of using stem cells to treat IPF and other lung fibrosis diseases. Stem cells are immature cells that can proliferate and turn into adult cells in order to, for example, repair injuries. Some types of stem cells have anti-inflammatory and anti-fibrosis properties that make them particularly attractive as potential treatments for fibrosis diseases.

Cheng and Lobo have focused on a set of stem cells and support cells that reside in the lungs and can be reliably cultured from biopsied lung tissue. The cells are called lung spheroid cells for the distinctive sphere-like structures they form in culture. As the scientists reported in an initial paper in 2015, lung spheroid cells showed powerful regenerative properties when applied to a mouse model of lung fibrosis. In their therapeutic activity, these cells also outperformed other non-lung-derived stem cells known as mesenchymal stem cells, which are also under investigation to treat fibrosis.

In the first of the two new studies, Lobo and his team showed that they could obtain lung spheroid cells from human lung disease patients with a relatively non-invasive procedure called a transbronchial biopsy.

“We snip tiny, seed-sized samples of airway tissue using a bronchoscope,” Lobo said. “This method involves far less risk to the patient than does a standard, chest-penetrating surgical biopsy of lung tissue.”

Cheng and his colleagues cultured lung spheroid cells from these tiny tissue samples until they were numerous enough – in the tens of millions – to be delivered therapeutically. When they infused the cells intravenously into mice, they found that most of the cells gathered in the animals’ lungs.

“These cells are from the lung, and so in a sense they’re happiest, so to speak, living and working in the lung,” Cheng said.

In the second study, the researchers first induced a lung fibrosis condition in rats. The condition closely resembled human IPF. Then the researchers injected the new cultured spheroid cells into one group of rats. Upon studying this group of animals and another group treated with a placebo, the researchers saw healthier overall lung cells and significantly less lung inflammation and fibrosis in the rats treated with lung spheroid cells.

“Also, the treatment was safe and effective whether the lung spheroid cells were derived from the recipients’ own lungs or from the lungs of an unrelated strain of rats,” Lobo said. “In other words, even if the donated stem cells were ‘foreign,’ they did not provoke a harmful immune reaction in the recipient animals, as transplanted tissue normally does.”

Lobo and Chen expect that when used therapeutically in humans, lung spheroid cells initially would be derived from the patient to minimize any immune-rejection risk. Ultimately, however, to obtain enough cells for widespread clinical use, doctors might harvest them from healthy volunteers, as well as from whole lungs obtained from organ donation networks. The stem cells could later be used in patients as-is or matched immunologically to recipients in much the same way transplanted organs are typically matched.

“Our vision is that we will eventually set up a universal cell donor bank,” Cheng said.

Cheng, Lobo, and their teams are now planning an initial study of therapeutic lung spheroid cells in a small group of IPF patients and expect to apply later this year for FDA approval of the study. In the long run, the scientists hope their lung stem cell therapy will also help patients with other lung fibrosis conditions of which there are dozens, including COPD, cystic fibrosis, and fibro-cavernous pulmonary tuberculosis.

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Study uncovers potential ‘silver bullet’ for preventing and treating colon cancer

In preclinical experiments, researchers at VCU Massey Cancer Center have uncovered a new way in which colon cancer develops, as well as a potential “silver bullet” for preventing and treating it. The findings may extend to ovarian, breast, lung, prostate and potentially other cancers that depend on the same mechanism for growth.

Led by Massey’s Deputy Director Steven Grossman, M.D., Ph.D., a team of scientists targeted the gene CtBP with a drug known as HIPP (2-hydroxy-imino phenylpyruvic acid) and were able to reduce the development of pre-cancerous polyps by half and return a normal lifespan to mice born with a predisposition to intestinal polyps. In humans, this condition is known as familial adenomatous polyposis, a devastating inherited disease that causes pre-cancerous polyps to grow in the intestine at a young age, often leading to the removal of portions of the colon to prevent cancer.

“This work opens up a whole new avenue for anti-cancer therapeutic development, as it shows that CtBP drives the actions of what are known as cancer stem cells, which are keys to cancer metastasis and resistance to chemotherapy,” says Grossman, who is also the Dianne Nunnally Hoppes Endowed Chair in Cancer Research and co-leader of the Developmental Therapeutics research program at Massey as well as professor and chair of the Division of Hematology, Oncology and Palliative Care in the Department of Internal Medicine at the VCU School of Medicine.

In contrast to other cancer-promoting genes, CtBP is not mutated in colon cancer; instead, it is overexpressed to the point where the cancer depends on it for growth. CtBP works to reprogram cells by repressing the expression of genes that typically prevent cancer through a form of cell suicide known as apoptosis while simultaneously promoting the expression of other genes that lead to cancer growth and metastasis.

The researchers found that CtBP can cause normal human cells to become cancerous when inserted into the cell’s DNA. In mouse models of familial adenomatous, treatment with HIPP significantly reduced intestinal polyps and increased survival while mice bred without the CtBP gene lived twice as long as those with it.

“In our experiments, HIPP acted almost as a chemical ‘silver bullet’ to prevent polyp formation, thereby reducing the risk of colon cancer,” says Grossman. “Also, we believe that anti-CtBP therapies such as HIPP may be able to complement current therapies to counter drug resistance and decrease metastasis, ultimately increasing our ability to control and cure colon cancer.”

This study is the latest in a line of research investigating CtBP by Grossman and his colleagues that began in 2010. Moving forward, they plan to continue testing derivatives of HIPP for the treatment of colon cancer and also see if their findings extend to breast, lung, ovarian and prostate cancers.

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Identification of PTPRZ as a drug target for cancer stem cells in glioblastoma

Glioblastoma is the most malignant brain tumor with high mortality. Cancer stem cells are thought to be crucial for tumor initiation and its recurrence after standard therapy with radiation and temozolomide (TMZ) chemotherapy. Protein tyrosine phosphatase receptor type Z (PTPRZ) is an enzyme that is highly expressed in glioblastoma, especially in cancer stem cells.

The research group of Professor Masaharu Noda and Researcher Akihiro Fujikawa of the National Institute for Basic Biology (NIBB) showed that the enzymatic activity of PTPRZ is requisite for the maintenance of stem cell properties and tumorigenicity in glioblastoma cells. PTPRZ knockdown strongly inhibited tumor growth of C6 glioblastoma cells in a mouse xenograft model. In addition, the research team discovered NAZ2329, an allosteric inhibitor of PTPRZ, in collaboration with ASUBIO Pharma Co. Ltd.. NAZ2329 efficiently suppressed stem cell-like properties of glioblastoma cells in culture, and tumor growth in C6 glioblastoma xenografts. These results indicate that pharmacological inhibition of PTPRZ is a promising strategy for the treatment of malignant gliomas.

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Genetically enhanced, cord-blood derived immune cells strike B-cell cancers

Immune cells with a general knack for recognizing and killing many types of infected or abnormal cells also can be engineered to hunt down cells with specific targets on them to treat cancer, researchers at The University of Texas MD Anderson Cancer Center report in the journal Leukemia.

The team’s preclinical research shows that natural killer cells derived from donated umbilical cords can be modified to seek and destroy some types of leukemia and lymphoma. Genetic engineering also boosts their persistence and embeds a suicide gene that allows the modified cells to be shut down if they cause a severe inflammatory response.

A first-in-human phase I/II clinical trial of these cord-blood-derived, chimeric antigen receptor-equipped natural killer cells opened at MD Anderson in June for patients with relapsed or resistant chronic lymphocytic leukemia (CLL), acute lymphocytic leukemia (ALL), or non-Hodgkin lymphoma. All are cancers of the B cells, another white blood cell involved in immune response.

“Natural killer cells are the immune system’s most potent killers, but they are short-lived and cancers manage to evade a patient’s own NK cells to progress,” said Katy Rezvani, M.D., Ph.D., professor of Stem Cell Transplantation and Cellular Therapy.

“Our cord-blood derived NK cells, genetically equipped with a receptor that focuses them on B-cell malignancies and with interleukin-15 to help them persist longer — potentially for months instead of two or three weeks — are designed to address these challenges,” Rezvani said.

Moon Shots Program funds project

The clinical trial is funded by MD Anderson’s Moon Shots Program™, designed to more rapidly develop life-saving advances based on scientific discoveries.

The chimeric antigen receptor (CAR), so-called because it’s added to the cells, targets CD19, a surface protein found on B cells.

In cell lines and mouse models of lymphoma and CLL, CD19-targeted NK cells killed cancer cells and extended survival of animals compared to simply giving NK cells alone. Addition of IL-15 to the CD19 receptor was crucial for the longer persistence and enhanced activity of the NK cells against tumor cells.

NK cells are a different breed of killer from their more famous immune system cousins, the T cells. Both are white blood cells, but T cells are highly specialized hunters that look for invaders or abnormal cells that bear a specific antigen target, kill them and then remember the antigen target forever.

Natural killers have an array of inhibitory and activating receptors that work together to allow them to detect a wider variety of infected, stressed or abnormal cells.

“By adding the CD19 CAR, we’re also turning them into guided missiles,” said Elizabeth Shpall, M.D., professor of Stem Cell Transplantation and Cell Therapy.

Using a viral vector, the researchers transduce NK cells taken from cord blood with the CD19 CAR, the IL-15 gene, and an inducible caspase-9-based suicide gene.

Cell line tests found the engineered NK cells to be more efficient killers of lymphoma and CLL cells, compared to unmodified NK cells, indicating the engineered cells’ killing was not related to non-specific natural killer cell cytotoxicity.

Another experiment showed the engineered cord blood NK cells killed CLL cells much more efficiently than NK cells taken from CLL patients and engineered, highlighting the need to transplant CAR-engineered NK cells from healthy cord blood rather than use a patient’s own cells.

Suicide gene to counter cytokine release syndrome

Mouse model lymphoma experiments using a single infusion of low dose NK cells resulted in prolongation of survival. At a higher, double dose, none of the mice treated with the CD19/IL-15 NK cells died of lymphoma, with half surviving for 100 days and beyond. All mice treated with other types of NK cells died by day 41.

A proportion of mice treated with the higher dose of engineered NK cells died of cytokine release syndrome, a severe inflammatory response that also occurs in people treated with CAR T cells.

To counteract this toxicity, the researchers incorporated a suicide gene (iC9) that can be activated to kill the NK cells by treatment with a small-molecule dimerizer. This combination worked to swiftly reduce the engineered NK cells in the mouse model.

Subsequent safety experiments were conducted in preparation for the clinical trial. Rezvani, the principal investigator of the clinical trial, says the protocol calls for vigilance for signs of cytokine release syndrome, treatment with steroids and tocilizumab for low-grade CRS with AP1903 added to activate the suicide gene for grade 3 or 4 CRS.

NK CARs available off the shelf

T cells modified with chimeric antigen receptors against CD19 have shown efficacy in clinical trials. In these therapies, a patient’s own T cells are modified, expanded, and given back to the patient, a process that takes weeks. Finding a matched donor for T cells would be a challenge, but would be necessary because unmatched T cells could attack the recipient’s normal tissue – graft vs. host disease.

Rezvani and Shpall have given patients cord-blood derived NK cells in a variety of clinical trials and found that they do not cause graft vs. host disease, therefore don’t have to be matched. NK cells can be an off-the-shelf product, prepared in advance with the necessary receptor and given promptly to patients.

“CAR NK cells are scalable in a way that CAR T cells are not,” Rezvani noted.

A strength of T cells is the development of memory cells that persist and repeatedly attack cells bearing the specific antigen that return. NK cells do not seem to have a memory function, but Rezvani says the experience of the longer-lived mice, which are now more than a year old, raises the possibility that a prolonged NK cell attack will suffice.

Shpall, Rezvani and colleagues are developing cord blood NK CARs for other targets in a variety of blood cancers and solid tumors.

MD Anderson and the researchers have intellectual property related to the engineered NK cells, which is being managed in accordance with the institution’s conflict-of-interest rules.

Shpall founded and directs MD Anderson’s Cord Blood Bank, originally established to provide umbilical cord blood stem cells for patients who need them but cannot get a precise donor match. Donated by mothers who deliver babies at seven Houston hospitals and two others from California and Michigan, the bank now has 26,000 cords stored. MD Anderson researchers pioneered the extraction and expansion of NK cells from umbilical cords.

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Targeted drug shows promise in rare advanced kidney cancer

Some patients with a form of advanced kidney cancer that carries a poor prognosis benefited from an experimental drug targeted to an abnormal genetic pathway causing cancerous growth, according to research led by a Dana-Farber Cancer Institute scientist.

The drug, savolitinib, showed clinical activity in patients with metastatic papillary renal cell carcinoma (PRCC) whose tumors were driven by overactivity of the MET signaling pathway, but was not effective for patients whose tumors lacked the MET abnormality, said the investigators, led by Toni Choueiri, MD, director, Lank Center for Genitourinary Oncology, and director, Kidney Cancer Center, both of Dana-Farber.

These results from a single-arm, multicenter phase II clinical trial, reported in the Journal of Clinical Oncology, suggest that savolitinib holds promise as a personalized treatment for a subgroup of patients with metastatic papillary renal cell carcinoma, the researchers said.

In the US alone, about 6,400 cases of PRCC are expected to be diagnosed in 2017, compared to a total of 64,000 cases of kidney cancers. The majority of them are classified as clear cell renal cell cancers. Papillary renal cell carcinoma are non-clear cell kidney cancers. No good treatments exist for advanced or metastatic PRCC.

The current trial tested savolitinib, a potent and selective MET inhibitor, in 109 patients with locally advanced or metastatic PRCC. Of the 109 patients, 40 percent had tumors driven by MET, 42 percent had tumors that did not rely on MET, and MET status was unknown in 17 percent of patients.

When the results were analyzed, 18 percent of patients with MET-driven cancers had significant shrinkage of their tumors, and 50 percent had stable disease. By contrast, none of the patients with MET-independent tumors had shrinkage response, and only 24 percent had stable disease.

In addition, the length of time after treatment before the cancer began growing was significantly longer in the MET-driven tumor group – 6.2 months versus 1.4 months.

“These data support the hypothesis that savolitinib has antitumor activity in patients with MET-driven papillary renal cell carcinoma,” the authors wrote. “Our study identified a defined molecular group and highlights the prevalence of MET-driven disease in this rare population of RCC patients.”

Although some patients had their dosage of savolitinib reduced and two patients discontinued treatment because of side effects, the researchers said the drug was generally well-tolerated.

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Genetic modifier for Huntington’s disease progression identified

A team led by UCL and Cardiff University researchers has developed a novel measure of disease progression for Huntington’s disease, which enabled them to identify a genetic modifier associated with how rapidly the disease progresses.

“We’ve identified a gene that could be a target for treating Huntington’s disease. While there’s currently no cure for the disease, we’re hopeful that our finding could be a step towards life-extending treatments,” said Dr Davina Hensman Moss (UCL Huntington’s Disease Centre, UCL Institute of Neurology), one of the lead authors of the Lancet Neurology study.

Huntington’s disease (HD) is a fatal neurological disease caused by a genetic mutation. Larger mutations are linked to rapidly progressing disease, but that does not account for all aspects of disease progression. Understanding factors which change the rate of disease progression can help direct drug development and therapies.

The research team used the high quality phenotypic data from the intensively studied TRACK-HD cohort of people with the HD gene mutation. They established that different symptoms of disease progress in parallel, so they were able to combine the data from 24 cognitive, motor and MRI brain imaging variables to generate their progression score for genetic analysis.

They then looked for areas of the genome associated with their progression measure, and found a significant result in their sample of 216 people, which they then validated in a larger sample of 1773 people from a separate cohort, the European Huntington’s Disease Network (EHDN) REGISTRY study.

The genetic signal is likely to be driven by the gene MSH3, a DNA repair gene which has been linked to changes in size of the HD mutation. The researchers identified that a variation in MSH3 encodes an amino acid change in the gene. MSH3 has previously been extensively implicated in the pathogenesis of HD in both mouse and cell studies. The group’s findings may also be relevant to other diseases caused by repeats in the DNA, including some spinocerebellar ataxias.

Dr Hensman Moss said: “The gene variant we pinpointed is a common variant that doesn’t cause problems in people without HD, so hopefully it could be targeted for HD treatments without causing other problems.”

Professor Lesley Jones (Cardiff University), who co-led the study, said: “The strength of our finding implies that the variant we identified has a very large effect on HD, or that the new progression measure we developed is a much better measure of the relevant aspects of the disease, or most likely, both.”

The researchers say their study demonstrates the value of getting high quality data about the people with a disease when doing genetic studies.

Professor Sarah Tabrizi (UCL Huntington’s Disease Centre), who co-led the study said: “This is an example of reverse translation: these novel findings we observed in people with HD support many years of basic laboratory work in cells and mice. Now we know that MSH3 is critical in the progression of HD in patients, we can focus our attention on it and how this finding may be harnessed to develop new therapies that slow disease progression.”

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International study identifies new genetic risk factors for testicular cancer

Testicular cancer is relatively rare with only 8,850 cases expected this year in the United States. A majority of testicular cancer, 95 percent of all cases, begins in testicular germ cells, which are the cells responsible for producing sperm. Testicular germ cell tumors (TGCT) are the most common cancer in men aged 20 to 39 years in the U.S. and Europe. Peter Kanetsky, Ph.D., M.P.H., chair of the Cancer Epidemiology Department at Moffitt Cancer Center, and colleagues from the International TEsticular CAncer Consortium (TECAC), launched a large analysis of five major testicular cancer studies to investigate genetic risk factors linked to TGCT. Their results, which uncovered eight new genetic markers associated with TGCT, were published in the June 12 issue of Nature Genetics.

The incidence of TGCT has been increasing around the world throughout the past 50 years. Between 1973 and 2003, the number of men diagnosed with TGCT rose by 54 percent. TGCT is also more prevalent in certain populations. Men who are of Northern European ancestry have the highest incidence of TGCT, while men of African decent have the lowest incidence.

Scientists are unsure why the incidence of TGCT has been increasing or why it is more prevalent in certain populations. Their goal is to identify risk factors for TGCT to increase their understanding of how it arises and to identify those patients who may develop TGCT to prevent progression and treat the disease earlier.

It is believed that some TGCT risk factors may be inherited. Men who have a father with TGCT are four times more likely to develop it, and the risk increases eight-fold if they have a brother with TGCT. Approximately 30 genetic risk factors have been identified so far, but these do not completely account for all of the potential heritable risks.

TECAC combined data from five previous genome-wide association studies, providing researchers with more than 3,500 TGCT cases internationally to review. Their analysis identified eight new genetic markers that are associated with an increased risk of developing TGCT and refined four previously reported susceptibility regions.

“Our findings substantially increase the number of known susceptibility genes associated with TGCT. This moves the field closer to a comprehensive understanding of the underlying genetic architecture and development of the disease,” Kanetsky said.

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Altered virus may expand patient recruitment in human gene therapy trials

For many patients, participating in gene therapy clinical trials isn’t an option because their immune system recognizes and fights the helpful virus used for treatment. Now, University of Florida Health and University of North Carolina researchers have found a solution that may allow it to evade the body’s normal immune response.

The discovery, published May 29 in the Proceedings of the National Academy of Sciences, is a crucial step in averting the immune response that prevents many people from taking part in clinical trials for various disorders, said Mavis Agbandje-McKenna, Ph.D., a professor in the University of Florida College of Medicine department of biochemistry and molecular biology and director of the Center for Structural Biology.

During gene therapy, engineered viruses are used to deliver new genes to a patient’s cells. While the recombinant adeno-associated virus, or AAV, is effective at delivering its genetic cargo, prior natural exposure to AAV results in antibodies in some people. As many as 70 percent of patients have pre-existing immunity that makes them ineligible for gene therapy clinical trials, Agbandje-McKenna said.

The findings provide a road map for designing virus strains that can evade neutralizing antibodies, said Aravind Asokan, Ph.D., an associate professor in the department of genetics at the University of North Carolina, who led the study. At UF Health, the structural “footprints” where pre-existing antibodies interact with the virus were identified using cryo-electron microscope resources provided by the UF College of Medicine and the UF Office of Research’s Division of Sponsored Programs. The UNC researchers then evolved new viral protein shells. Using serum from mice, rhesus monkeys and humans, the researchers showed that the redesigned virus can slip past the immune system.

“This is the blueprint for producing AAV strains that could help more patients become eligible for human gene therapy. Now we know how to do it,” Agbandje-McKenna said.

While the findings prove that one variation of AAV can be evolved, further study in preclinical models is needed before the approach can be tested in humans. Next, the immune profile of one particularly promising virus variant will need to be evaluated in a larger number of human serum samples, and dose-finding studies are needed in certain animal models. Researchers may also need to study whether the same virus-manipulating technique can be used in a broader range of gene therapy viruses, Agbandje-McKenna said.

Although human gene therapy remains an emerging field and has yet to reach patients on a wide scale, researchers elsewhere have used AAV therapy to successfully treat hemophilia, a blood-clotting disorder, in a small trial. It has also been or is now being studied as a way to treat hereditary blindness, certain immune deficiencies, neurological and metabolic disorders, and certain cancers.

The latest findings are the result of more than 10 years of studying the interactions between viruses and antibodies and a long-standing collaboration with Asokan, who heads the synthetic virology group at the UNC Gene Therapy Center, according to Agbandje-McKenna.

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Alectinib halts lung cancer growth more than a year longer than crizotinib

Findings from a phase III clinical trial point to a more effective initial treatment for patients with ALK-positive non-small cell lung cancer (NSCLC). Compared to the current standard of care crizotinib (Xalkori), the newer ALK inhibitor alectinib (Alecensa) halted cancer growth for a median of 15 months longer and caused fewer severe side effects.

The study was featured in a press briefing today and presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting.

“This is the first global study to compare alectinib with crizotinib in ALK-positive lung cancer and establishes alectinib as the new standard of care for initial treatment in this setting,” said lead study author Alice T. Shaw, MD, PhD, Director of Thoracic Oncology at Massachusetts General Hospital Cancer Center in Boston, MA. “Alectinib was especially beneficial in controlling and preventing brain metastases, which can have a major impact on patients’ quality of life.”

About 5% of NSCLCs are ALK-positive, meaning they have a genetic rearrangement where the ALK gene is fused with another gene. In the United States, about 12,500 people are diagnosed with ALK-positive NSCLC each year.

Crizotinib, the first medicine to specifically target ALK, was approved by the FDA in 2011. Although the majority of patients initially benefit from crizotinib, the cancer typically starts growing again within a year. Alectinib is a more potent, next-generation inhibitor of ALK. It was initially approved in 2015 for use in patients with advanced NSCLC that worsens despite crizotinib.

“The fact that this second-generation targeted treatment halted advanced lung cancer growth for more than two years while preventing brain metastases is a remarkable result in this difficult disease,” said ASCO Expert John Heymach, MD, PhD. “Thanks to this advance, we are on the road to helping these patients live longer and better.”

About the Study

In this open label clinical trial (ALEX), researchers randomly assigned 303 patients with stage IIIB or IV, ALK-positive NSCLC to receive alectinib or crizotinib. The patients had not received prior systemic therapy for advanced NSCLC.

Key Findings

Alectinib reduced the risk of cancer progression or death by 53% compared with crizotinib. Based on independent review, alectinib extended the median time to progression by about 15 months (median progression-free survival was 25.7 months with alectinib and 10.4 months with crizotinib).

“Nobody imagined it would be possible to delay advanced lung cancer progression by this much. Most targeted therapies for lung cancer are associated with a median progression-free survival of roughly 12 months,” said Dr. Shaw.

While both treatments cross the blood-brain barrier, alectinib was more effective in preventing brain metastases than crizotinib, because it can better penetrate into the brain. At 12 months, the incidence of brain metastases was much lower with alectinib than with crizotinib (9% vs. 41%).

Overall, severe side effects were less common with alectinib than with crizotinib, occurring in 41% vs. 50% of patients. The most common side effects of alectinib were fatigue, constipation, muscle aches, and swelling, whereas crizotinib caused gastrointestinal problems and liver enzyme abnormalities.

Next Steps

The researchers will continue to follow patients on this study to see if those treated with alectinib live longer than those treated with crizotinib. Meanwhile, several ongoing clinical trials are comparing other next-generation ALK inhibitors to crizotinib in the first-line setting.

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Clinical trial shows experimental drug’s ability to knock down pancreatic cancer’s defense

By adding an experimental drug to a standard chemotherapy regimen, a subset of patients with metastatic pancreatic cancer had a significantly longer period before the cancer progressed as compared with those who received the standard treatment, according to a Phase 2 clinical trial led by an investigator at Fred Hutchinson Cancer Research Center.

The randomized, controlled trial found that when the experimental therapy was given to participants whose tumors had a lot of the drug’s target molecule, they had four months more of progression-free survival than participants in the control group who only had the chemo.

For anyone not familiar with the rapid deadliness of pancreatic cancer, it may be hard to see the significance of the few additional months before disease progression. But time is precious for patients with this cancer: Only about 8 percent of all pancreatic cancer patients survive five years after diagnosis.

Dr. Sunil Hingorani, the faculty member at Fred Hutch who led the trial, is scheduled to present the findings at 10:24 a.m., June 4, at the American Society of Clinical Oncology annual meeting in Chicago. ASCO abstract number 4008.

Hingorani said that the results reassure him that it was the right move to advance the drug, called PEGPH20, into the worldwide Phase 3 trial that opened last year.

“We still haven’t fully proven anything yet, strictly speaking, but I think [this strategy] is very rational,” he said. “Let me put it this way: I think it would be irresponsible not to finish the global Phase 3 trial as the most rigorous test of this hypothesis. I think we’re obligated now to answer the question.”

Hingorani consults for Halozyme, the PEGPH20 drugmaker and the sponsor of these trials. The company began this year to provide funding through Fred Hutch to support Hingorani’s research on the drug.

Hingorani’s earlier research led him to the drug because he believed it could address a challenge posed by many pancreatic cancers: The tumors have very high internal pressures that collapse local blood vessels and prevent cancer-killing drugs from getting in. PEGPH20 reduces those pressures so chemotherapies circulating in the blood can penetrate tumors.

The experimental drug, which was created from the blueprint of a naturally occurring enzyme, breaks down a molecule called hyaluronic acid that is produced in bulk by many pancreatic cancers.

Hyaluronic acid, or HA, is naturally found in the human body; it readily binds water to create a gel fluid, making it an excellent shock-absorber in your knees, for example. But in pancreatic tumors, it spells trouble. As the gel fluid builds up, it raises the tumor’s internal pressure, squeezing local blood vessels shut. Patients whose tumors have a lot of HA also tend to have a poor prognosis.

Hingorani and his team first conducted studies in mice that showed how PEGPH20, in combination with chemo, permanently reduced the amount of pressure-boosting HA inside the mouse tumors. It caused the tumors to shrink and increased the mice’s survival time.

In the Phase 2 trial, patients with late-stage pancreatic cancer were randomly assigned to receive a standard-of-care, first-line combination chemotherapy either with or without PEGPH20. When the results of all 234 evaluable patients on Halo 202 were grouped together, the apparent benefit of PEGPH20 was small ? a matter of just a couple extra weeks of progression-free survival.

“If this was all the potential that this strategy represented, I wouldn’t pursue this [research further],” Hingorani said. “That’s not enough for me.”

But a stark difference emerged when the results were divided up by how much of the drug’s target, HA, patients’ tumors contained: In the subset of 80 patients whose tumors had high levels of HA, adding PEGPH20 to chemo resulted in an average of 9.2 months before disease progression; with chemo alone, this timespan was just 5.2 months.

Hingorani also reported that the unexpected, elevated risk of blood clots associated with PEGPH20 ? which resulted in a temporary halt of the trial in 2014 ? equalized between the patients receiving PEGPH20 and those in the control group, and dropped overall, after the study was restarted, due to the addition of a blood thinner to all patients’ regimens.

“These are the real take-home messages to me, namely, the progression-free survival in target-rich [high-HA] patients and the ability to give the enzyme safely,” Hingorani said.

Because the Phase 2 trial results suggest that the benefit of the experimental drug is restricted to the patients with high levels of HA in their tumors, only patients with such tumors qualify for the new Phase 3 trial. And the Phase 3 trial is designed to offer a more stringent test of the benefits of the new drug than its predecessor: Aimed at advancing the drug toward potential FDA approval, the trial’s goal is to determine whether PEGPH20 actually increases participants’ lifespans, not just their time to disease progression. (It’s possible a treatment could achieve the latter without impacting the former.)

The investigators’ exploratory analysis of the Phase 2 trial data suggested that the experimental drug boosted the lifespans of patients with high-HA tumors to an average of nearly a year after diagnosis ? which, if shown definitively in the Phase 3 trial, could be a new benchmark for this cancer, Hingorani said.

Hingorani launched the Phase 3 trial before handing off its leadership to two other colleagues in the field, Dr. Margaret Tempero of the University of California, San Francisco and Dr. Eric Van Cutsem at the University of Leuven in Belgium. As he steps back from his leadership role on this project, Hingorani is satisfied by the solid scientific foundation the investigators have lain to justify moving forward with the development of this drug.

In light of the grim timelines associated with a pancreatic cancer diagnosis, he said, patients have no time to waste on anything less.

“Patients get one shot on goal, if that, with this cancer,” he said. “No cancer is more daunting than pancreas cancer.”

Treatment-related adverse events for trial participants included peripheral edema (63 percent of those receiving PEGPH20 vs. 26 percent for the control group), muscle spasms (56 percent vs 3 percent), neutropenia (34 percent vs 19 percent), and myalgia (26 percent vs. 7 percent).

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Cancer therapy shows promise for psoriasis treatment

HDAC inhibitors, already widely used to treat cancer, may be an effective therapy for psoriasis as well, scientists report.

They have shown that HDAC3 inhibitors are particularly adept at increasing expression of aquaporin-3, or AQP3, a channel that transports glycerin, a natural alcohol and water attractor, which helps skin look better and aids healthy production and maturation of high-turnover skin cells.

“We’ve found that HDAC3 normally inhibits expression of AQP3 and we think we can use this knowledge to treat patients with psoriasis,” said Dr. Vivek Choudhary, molecular biologist and physiologist in the Department of Physiology at the Medical College of Georgia at Augusta University.

MCG scientists knew that AQP3 levels were lower in psoriasis than in healthy skin, said Choudhary, corresponding author of the study in the Journal of Investigative Dermatology. The protein helps skin cells proliferate, differentiate into the right kind of cells and get to the right location in the body. It also aids the skin’s hydration, wound recovery and elasticity. Histone deacetylase, which they found suppresses AQP3, helps regulate gene expression and protein function.

Since the immune system is believed to play a key role in psoriasis, many current treatments generally suppress the immune response, which increases the risk of infections, even cancer. MCG scientists hope they can one day instead directly enhance the presence of AQP3 or maybe its key cargo glycerin.

Psoriasis is one of the most common skin disorders, with red, flaky patches most often erupting on the elbows, knees, scalp and back, said Dr. Wendy B. Bollag, cell physiologist in the MCG Department of Physiology and the study’s senior author.

Like cancer, inflammation and excessive proliferation of cells are a psoriasis hallmark. That common ground and other emerging clues got the scientists thinking about the treatment potential of HDAC inhibitors. But first they had to establish a relationship.

When they introduced a broad-acting HDAC inhibitor to normal skin cells, or keratinocytes, – both mouse and human – they found expression of AQP3 went up within 24 hours, the first time the relationship had been noted.

They reiterated that AQP3 was critical because when it was missing, there was no commensurate increase in glycerin. AQP3 knockout mice also further clarified AQP3’s role in skin hydration, elasticity and wound healing and that it is glycerin – rather than water – that is most key to these healthy functions.

They also found that p53, a known, natural tumor suppressor that also supports cell differentiation, helps the HDAC inhibitors enable more AQP3 and ultimately more glycerin, Choudhary said. HDACs also are known to inhibit p53 activity. However overexpressing p53 by itself did not result in increased functional levels of AQP3, the scientists found.

The MCG scientists first used the HDAC inhibitor, suberoylanilide hydroxamic acid, or SAHA, which was approved by the Food and Drug Administration more than a decade ago to treat cutaneous T cell lymphoma, which has symptoms that can include dry, itchy skin as well as enlarged lymph nodes.

“We think this is one of the ways it works,” Bollag said of SAHA and their new findings. They also used several other HDAC inhibitors and found the ones that suppressed HDAC3 were also most effective at increasing AQP3.

AQP3 is adept at hauling glycerin, the backbone of many lipids and typically a key ingredient in skin lotion. Bollag’s lab reported in the Journal of Investigative Dermatology in 2003 that glycerin helps skin cells mature properly. Inside skin cells, phospholipase D – an enzyme that converts fats or lipids in the external protective cell membrane into cell signals – and AQP3 interact. AQP3 hands off glycerin, which produces phosphatidylglycerol, which, in turn, aids skin cell differentiation.

“We think phosphatidylglycerol is the key,” Bollag said of the positive results. “If you don’t have enough, you may have psoriasis.”

The Bollag lab and others also had found that AQP3, which is present in psoriasis, appears rather immature and out of place, largely inside the cell cytoplasm instead of on the protective, outer cell membrane. The inner location puts quite a damper on its normal mature function of transporting glycerin, water and other substances through the membrane.

“If you use antibodies to visualize where AQP3 is in the keratinocytes, you will see it nicely outlining the cells because it’s right there on the plasma membrane,” Bollag said. “So clearly it’s normally expressed in keratinocytes but the fact that we can upregulate it even more with an HDAC3 inhibitor suggests that normally HDAC3 keeps it in check.”

Cambridge, Massachusetts-based biotech company Shape Pharmaceuticals Inc., currently has a topical version of an HDAC inhibitor in clinical trials for cutaneous T cell lymphoma. If psoriasis patients end up taking HDAC inhibitors, low doses or a topical application likely would help avoid some side effects, including nausea, Bollag said.

One way HDAC inhibitors help fight cancer is by temporarily loosening DNA, increasing the expression of tumor-suppressing genes and making the tumor more vulnerable. HDAC inhibitors also are being explored for their potential in treating neurological diseases such as Huntington’s.

Others have provided evidence that dysregulation of AQP3 contributes to psoriasis and AQP3 is linked to other skin diseases as well like atopic dermatitis – the most common type of eczema and vitiligo, which results in white patches on the skin.

Interestingly, even though psoriatic cells are known for their propensity to replicate, it’s hard to grow an adequate number of cells for scientific study: they increase a certain amount then go quiet. There also is no real animal model of psoriasis. Moving forward, the MCG scientists may try developing a model using a topical drug for genital warts since some patients who take it develop psoriasis.

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Engineers design a new weapon against bacteria

Over the past few decades, many bacteria have become resistant to existing antibiotics, and few new drugs have emerged. A recent study from a U.K. commission on antimicrobial resistance estimated that by 2050, antibiotic-resistant bacterial infections will kill 10 million people per year, if no new drugs are developed.

To help rebuild the arsenal against infectious diseases, many scientists are turning toward naturally occurring proteins known as antimicrobial peptides, which can kill not only bacteria but other microbes such as viruses and fungi. A team of researchers at MIT, the University of Brasilia, and the University of British Columbia has now engineered an antimicrobial peptide that can destroy many types of bacteria, including some that are resistant to most antibiotics.

“One of our main goals is to provide solutions to try to combat antibiotic resistance,” says MIT postdoc Cesar de la Fuente. “This peptide is exciting in the sense that it provides a new alternative for treating these infections, which are predicted to kill more people annually than any other cause of death in our society, including cancer.”

De la Fuente is the corresponding author of the new study, and one of its lead authors along with Osmar Silva, a postdoc at the University of Brasilia, and Evan Haney, a postdoc at the University of British Columbia. Timothy Lu, an MIT associate professor of electrical engineering and computer science, and of biological engineering, is also an author of the paper, which appears in the Nov. 2 issue of Scientific Reports.

Improving on nature

Antimicrobial peptides, produced by all living organisms as part of their immune defenses, kill microbes in several different ways. First, they poke holes in the invaders’ cell membranes. Once inside, they can disrupt several cellular targets, including DNA, RNA, and proteins.

These peptides also have another critical ability that sets them apart from traditional antibiotics: They can recruit the host’s immune system, summoning cells called leukocytes that secrete chemicals that help kill the invading microbes.

Scientists have been working for several years to try to adapt these peptides as alternatives to antibiotics, as bacteria become resistant to existing drugs. Naturally occurring peptides can be composed of 20 different amino acids, so there is a great deal of possible variation in their sequences.

“You can tailor their sequences in such a way that you can tune them for specific functions,” de la Fuente says. “We have the computational power to try to generate therapeutics that can make it to the clinic and have an impact on society.”

In this study, the researchers began with a naturally occurring antimicrobial peptide called clavanin-A, which was originally isolated from a marine animal known as a tunicate. The original form of the peptide kills many types of bacteria, but the researchers decided to try to engineer it to make it even more effective.

Antimicrobial peptides have a positively charged region that allows them to poke through bacterial cell membranes, and a hydrophobic stretch that enables interaction with and translocation into membranes. The researchers decided to add a sequence of five amino acids that would make the peptides even more hydrophobic, in hopes that it would improve their killing ability.

This new peptide, which they called clavanin-MO, was very potent against many bacterial strains. In tests in mice, the researchers found that it could kill strains of Escherichia coli and Staphylococcus aureus that are resistant to most antibiotics.

Suppressing sepsis

Another key advantage of these peptides is that while they recruit immune cells to combat the infection, they also suppress the overactive inflammatory response that can cause sepsis, a life threatening condition.

“In this single molecule, you have a synthetic peptide that can kill microbes — both susceptible and drug-resistant — and at the same time can act as an anti-inflammatory mediator and enhance protective immunity,” de la Fuente says.

The researchers also found that these peptides can destroy certain biofilms, which are thin layers of bacterial cells that form on surfaces. That raises the possibility of using them to treat infections caused by biofilms, such as the Pseudomonas aeruginosa infections that often affect the lungs of cystic fibrosis patients. Or, they could be embedded into surfaces such as tabletops to make them resistant to microbial growth.

Other possible applications for these peptides include antimicrobial coatings for catheters, or ointments that could be used to treat skin infections caused by Staphylococcus aureus or other bacteria.

If these peptides are developed for therapeutic use, the researchers anticipate that they could be used either in stand-alone therapy or together with traditional antibiotics, which would make it more difficult for bacteria to evolve drug resistance. The researchers are now investigating what makes the engineered peptides more effective than the naturally occurring ones, with hopes of making them even better.

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The calling card of aggressive thyroid cancer

A new discovery from University of Alberta scientists represents an important milestone in the fight against thyroid cancer. In a study published in EBioMedicine and recently presented at the American Thyroid Association annual meeting, the team has identified a marker of aggressive disease for papillary thyroid cancer, which comprises about 90 per cent of all thyroid cancers. The marker–a protein known as Platelet Derived Growth Factor Receptor Alpha, or PDGFRA–could also be used as a therapeutic target for future treatments.

Todd McMullen, senior author and associate professor of surgery with the U of A‘s Faculty of Medicine & Dentistry, believes the findings will have a significant clinical impact.

“The big problem for individual patients and physicians is knowing if the patient has the disease that is easy to treat or if they have a more aggressive variant. A lot of patients get over-treated simply because we don’t want to miss the one case in five that may spread to other sites,” says McMullen.

“The only way to be sure it doesn’t spread is to undertake a larger surgery which can have lifelong consequences. Most of these patients are young. They have children. The majority tend to opt for the surgery because until now we haven’t had another tool to help them know when it is needed.”

Each year approximately 6,300 Canadians will be diagnosed with thyroid cancer. More than three quarters of those patients are women. Treatments for the disease include radioactive iodine therapy and surgery. Those who opt for aggressive surgery can see their speech affected, have trouble eating, swallowing and even breathing as a result.

“We came up with a tool to identify aggressive tumours so that people can have just the right amount of surgery. No more, no less,” says McMullen. “What we’re really excited about is that this is both a diagnostic tool and a therapy. It can be used to do both. We’ve identified the mechanism of how this protein actually drives metastasis in thyroid cancer. And not only that, we found out that it also makes the cancer resistant to radioactive iodine therapy.”

McMullen says that by identifying the mechanism, the team is able to predict which people will have recurrent disease and which patients will respond to radioactive iodine therapy–both tools that are currently lacking in the medical community.

The foundation of the work stems from previous efforts in which McMullen’s team examined thyroid cancer patient specimens. In a study published in 2012 they looked at genetic signatures showing which patients experienced metastasis and which patients did not. Through their efforts at that time they discovered PDGFRA was linked to metastatic disease. According to McMullen, this latest research significantly advances that work.

In the very near future the team hopes to begin two separate clinical trials. The first will investigate a new way to treat thyroid cancers using a cancer drug that specifically targets PDGFRA. The second will work on a new diagnostic tool to give patients an early indicator of whether their thyroid cancer will be aggressive or not.

“We hope within the next 18 months that we can prove the utility of this approach and change the way thyroid cancers are managed for those patients that have the worst disease,” says McMullen. “We were lucky enough to find something that we think is important for thyroid cancer. It will be put to the test now.”

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Heart disease, leukemia linked to dysfunction in nucleus

We put things into a container to keep them organized and safe. In cells, the nucleus has a similar role: keeping DNA protected and intact within an enveloping membrane. But a new study by Salk Institute scientists, detailed in the November 2 issue of Genes & Development, reveals that this cellular container acts on its contents to influence gene expression.

“Our research shows that, far from being a passive enclosure as many biologists have thought, the nuclear membrane is an active regulatory structure,” says Salk Professor Martin Hetzer, who is also holder of the Jesse and Caryl Philips Foundation chair. “Not only does it interact with portions of the genome to drive gene expression, but it can also contribute to disease processes when components are faulty.”

Using a suite of molecular biology technologies, the Salk team discovered that two proteins, which sit in the nuclear envelope, together with the membrane-spanning complexes they form, actively associate with stretches of DNA to trigger expression of key genes. Better understanding these higher-level functions could provide insight into diseases that appear to be related to dysfunctional nuclear membrane components, such as leukemia, heart disease and aging disorders.

Historically, the nuclear membrane’s main purpose was thought to be keeping the contents of the nucleus physically separated from the rest of the cell. Complexes of at least thirty different proteins, called nucleoporins, form gateways (pores) in the membrane, controlling what goes in or out. But as the Hetzer lab’s work on nucleoporins shows, these nuclear pore complexes (NPCs), beyond being mere gateways into the nucleus, have surprising regulatory effects on the DNA inside.

“Discovering that key regulatory regions of the genome are actually positioned at nuclear pores was very unexpected,” says Arkaitz Ibarra, a Salk staff scientist and first author of the paper. “And even more importantly, nuclear pore proteins are critical for the function of those genomic sites.”

Curious about all the regions of DNA with which nucleoporins potentially interact, the team turned to a human bone cancer cell line. The scientists used a molecular biology technique called DamID to pinpoint where two nucleoporins, Nup153 and Nup93, came into contact with the genome. Then they used several other sequencing techniques to understand which genes were being affected in those regions, and how.

The Salk team discovered that Nup153 and Nup93 interacted with stretches of the genome called super-enhancers, which are known to help determine cell identity. Since every cell in our body has the same DNA, what makes a muscle cell different from a liver cell or a nerve cell is which particular genes are turned on, or expressed, within that cell. In the Salk study, the presence of Nup153 and Nup93 was found to regulate expression of super-enhancer driven genes and experiments that silenced either protein resulted in abnormal gene expression from these regions. Further experiments in a lung cancer cell line validated the bone cancer line results: Nucleoporins in the NPC were found to interact with multiple super-enhancer regions to drive gene expression, while experiments that altered the NPC proteins made related gene expression faulty, even though the proteins still performed their primary role as gatekeepers in the cell membrane.

“It was incredible to find that we could perturb the proteins without affecting their gateway role, but still have nearby gene expression go awry,” says Ibarra.

The results bolster other work indicating that problems with the nuclear membrane play a role in heart disease, leukemia and progeria, a rare premature aging syndrome.

“People have thought the nuclear membrane is just a protective barrier, which is maybe the reason why it evolved in the first place. But there are many more regulatory levels that we don’t understand. And it’s such an important area because so far, every membrane protein that has been studied and found to be mutated or mis-localized, seems to cause a human disease,” says Hetzer.

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Doctors Look to Combination Drug to Treat Osteoarthritis Pain and Hypertension

Approximately half, or an estimated 13.5 million, of the 27 million Americans living with osteoarthritis pain also suffer from high blood pressure. Many of these 13.5 million people cannot take the standard drugs used to treat osteoarthritis pain, nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs raise the risk of further increasing blood pressure (hypertension), and potentially causing stroke or heart attacks. In July of 2015 the FDA issued a safety warning stating the risk of heart of attack associated with NSAIDs can occur as early as the first weeks of using an NSAID and the risks may increase with longer use. This leaves prescribing doctors in a difficult spot.

Non-compliance on the part of patients is also a large challenge for the healthcare system. Two-thirds of people living with hypertension lack proper control of their blood pressure due to not taking medication as prescribed. This leads to health risks and higher costs associated with hospitalization. Hospitalization costs were $3,500 more per non-compliant hypertension patient, as compared to compliant patients.

Kitov Pharmaceuticals’ combination drug KIT-302, which treats both osteoarthritis pain and hypertension in one pill, is a solution that doctors are now considering. It is designed to be a safer drug that virtually eliminates harmful side effects. The drug has completed a successful Phase 3 trial and is slated for NDA submission in the coming months. KIT-302 is comprised of two FDA-approved drugs, celecoxib (Celebrex®) for the treatment osteoarthritis pain and amlodipine besylate (amlodipine), a drug designed to treat hypertension.

In a recent market assessment, commissioned by Kitov, a third party payor which insures millions of covered lives, stated the following regarding KIT-302, “The actual idea that pain is a stimulant for compliance in brilliant.” Most payors were intrigued by the idea that people would be motivated to take their hypertension drug because it is in one tablet with their pain drug. Osteoarthritis pain relief drugs have a higher compliance rate due to the obvious reason: pain is a motivator to take a pill.

Of the 110 Key Opinion Leaders and high volume prescribers interviewed, including general practitioners, internal medicine, pain specialists, rheumatologists and orthopedic surgeons, doctors stated they would prescribe KIT-302 to 40% of their patients currently treated with celecoxib. They also reported they would prescribe KIT-302 to 25% of their osteoarthritis patients who are not being treated with celecoxib. The physicians’ predicted prescribing behavior was based on KIT-302’s target product profile from its Phase 3 clinical data.

Following submission of its NDA, Kitov hopes to get FDA clearance to market KIT-302 by the end of 2017 or beginning of 2018. Patients and doctors will have an alternative that is safe, effective and promotes higher compliance.

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University Of Southern California To Show How Wearable Technology Can Improve Cancer Treatment

Researchers at the University of Southern California will demonstrate how using wearable technology and smartphones can improve cancer treatment at a White House event on Oct. 3.

“South by South Lawn: A White House Festival of Ideas, Art and Action” (SXSL) is a gathering inspired by South by Southwest, the annual gathering of film, interactive media and conferences in Texas. It brings together creators, innovators and organizers who work to improve the lives of their fellow Americans and people around the world.

The USC project will be one of the participants in the Cancer Moonshot exhibit championed by Vice President Joe Biden. Researchers aim to provide doctors with real-time patient data from wearable technology and patient-reported experiences so that physicians can base their treatment decisions on objective measures rather than just subjective and episodic observations. The project is called Analytical Technologies to Objectively Measure Human Performance (ATOM-HP).

Jorge Nieva, ATOM-HP’s co-lead researcher and an associate professor of clinical medicine at the Keck School of Medicine of USC, said this approach will create a safety net for patients who have the hardest time with cancer treatments.

“Using technology to observe the experiences of our cancer patients while they are at home humanizes the impact of the therapy by making it visible in analytic form to the doctor,” Nieva said. “At a glance, we can see the days spent in bed, the impact of treatment on lifestyle and, in some cases, see those moments when we wish we had intervened before things got worse.”

Current cancer treatment is based on episodic encounters. Even during chemotherapy, patients generally see their physician for maybe eight to 10 minutes every three weeks, said Peter Kuhn, ATOM-HP’s co-lead researcher and a professor of medicine, biomedical engineering, and aerospace and mechanical engineering at the USC Dornsife College of Letters, Arts and Sciences.

“The more than 30,000 minutes between visits are a missed opportunity,” Kuhn said. “Technology can be leveraged to fill this gap and provide a comprehensive picture. The collected data can lead to better treatment decisions, better survival rates, and better understanding between physician and patient.”

ATOM-HP is a convergent science initiative bringing together collaborators from the USC Norris Comprehensive Cancer Center, the Keck School of Medicine, the USC Viterbi School of Engineering, USC Dornsife and the USC Jimmy Iovine and Andre Young Academy.

“As a university, we are making headway on multiple fronts to address the cancer crisis,” USC Provost Michael Quick said. “We have faculty, researchers and students across disciplines who are working collaboratively to fast track the detection of cancer and, ultimately, to find a cure for this disease. We strongly support this type of convergent science at USC, and we know we will have an impact on this widespread and devastating disease.”

The real-time data ATOM-HP provides likely will fast-track cancer research.

“One of the great barriers to solving the complicated cancer puzzle is a lack of timely information,” Kuhn said. “Analyses of cancer data usually become available years after the information was first collected. Having access to real-time data will be invaluable for scientists.”

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Changes Uncovered in the Gut Bacteria of Patients with Multiple Sclerosis

A connection between the bacteria living in the gut and immunological disorders such as multiple sclerosis have long been suspected, but for the first time, researchers have detected clear evidence of changes that tie the two together. Investigators from Brigham and Women’s Hospital (BWH) have found that people with multiple sclerosis have different patterns of gut microorganisms than those of their healthy counterparts. In addition, patients receiving treatment for MS have different patterns than untreated patients. The new research supports recent studies linking immunological disorders to the gut microbiome and may have implications for pursuing new therapies for MS.

“Our findings raise the possibility that by affecting the gut microbiome, one could come up with treatments for MS – treatments that affect the microbiome, and, in turn, the immune response,” said Howard L. Weiner, MD, director of the Partners MS Center and co-director of the Ann Romney Center for Neurologic Disease at Brigham Women’s Hospital, . “There are a number of ways that the microbiome could play a role in MS and this opens up a whole new world of looking at the disease in a way that it’s never been looked at before.”

Weiner and colleagues conducted their investigations using data and samples from subjects who are part of the CLIMB (Comprehensive Longitudinal Investigation of Multiple Sclerosis) study at Brigham and Women’s Hospital. The team analyzed stool samples from 60 people with MS and 43 control subjects, performing gene sequencing to detect differences in the microbial communities of the subjects.

Samples from MS patients contained higher levels of certain bacterial species – including Methanobrevibacter and Akkermansia – and lower levels of others – such as Butyricimonas – when compared to healthy samples. Other studies have found that several of these microorganisms may drive inflammation or are associated with autoimmunity. Importantly, the team also found that microbial changes in the gut correlated with changes in the activity of genes that play a role in the immune system. The team also collected breath samples from subjects, finding that, as a result of increased levels of Methanobrevibacter, patients with MS had higher levels of methane in their breath samples.

The researchers also investigated the gut microbe communities of untreated MS patients, finding that MS disease-modifying therapy appeared to normalize the gut microbiomes of MS patients. The researchers note that further study will be required to determine the exact role that these microbes may be playing in the progression of disease and whether or not modifying the microbiome may be helpful in treating MS. They plan to continue to explore the connection between the gut and the immune system in a larger group of patients and follow changes over time to better understand disease progression and interventions.

“This work provides a window into how the gut can affect the immune system which can then affect the brain,” said Weiner, who is also a professor of Neurology at Harvard Medical School. “Characterizing the gut microbiome in those with MS may provide new opportunities to diagnose MS and point us toward new interventions to help prevent disease development in those who are at risk.”