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Espaço de publicação e discussão sobre oncologia. GBM IMMUNOTHERAPY ONCO-VIRUS ONCOLOGY CANCER CHEMOTHERAPY RADIOTHERAPY


Quarta-feira, 19.08.15

ImmunoCellular signs agreement with FDA for phase 3 registrational trial of cancer immunotherapy ICT-107

GLIOBASTOMA GBM

ImmunoCellular signs agreement with FDA for phase 3 registrational trial of cancer immunotherapy ICT-107

Published on August 13, 2015 at 8:32 AM ·

ImmunoCellular Therapeutics, Ltd. ("ImmunoCellular") (NYSE MKT: IMUC) announced today that it has reached agreement with the US Food and Drug Administration (FDA) on a Special Protocol Assessment (SPA) for the phase 3 registrational trial of its cancer immunotherapy ICT-107 to treat patients with newly diagnosed glioblastoma.

The phase 3 trial is designed as a randomized, double-blind, placebo-controlled study of about 400 HLA-A2 positive subjects, which will be conducted at about 120 sites in the US, Canada and the EU. The primary endpoint in the trial is overall survival, which the FDA and EU regulators have stated is the appropriate endpoint for registrational clinical studies in glioblastoma. Secondary endpoints include progression-free survival and safety, as well as overall survival in the two pre-specified MGMT subgroups. Patient enrollment is anticipated to begin in the late third quarter or early fourth quarter of 2015.

A Special Protocol Assessment is a written agreement between the sponsor company and the FDA on the design, clinical endpoints, size and statistical design of a clinical trial intended to form the primary basis of an efficacy claim in the marketing application, such as a biologic licensing application (BLA) or a new drug application (NDA). Final marketing approval depends upon the safety and efficacy results demonstrated in the phase 3 clinical program.

Andrew Gengos, ImmunoCellular's Chief Executive Officer Commented: "We are pleased to have achieved this important milestone, and think that successful completion of the SPA process adds meaningful validation to the ICT-107 phase 3 program and design, especially the use of the gold standard primary endpoint of overall survival. With this SPA in place, we think that ICT-107 is uniquely positioned in the field of immuno-oncology approaches being tested in glioblastoma. We are making significant progress toward establishing our clinical site network and obtaining the necessary institutional review board approvals. We are confident that we are on track to begin patient enrollment in the late third quarter or early fourth quarter of this year."

Source:

ImmunoCellular Therapeutics, Ltd.

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por cyto às 11:37

Quinta-feira, 23.07.15

Magnetic nanoparticles may hold key to bringing immunotherapy into successful clinical use

 

Magnetic nanoparticles may hold key to bringing immunotherapy into successful clinical use

Published on July 16, 2015 at 1:54 AM

In recent years, researchers have hotly pursued immunotherapy, a promising form of treatment that relies on harnessing and training the body's own immune system to better fight cancer and infection. Now, results of a study led by Johns Hopkins investigators suggests that a device composed of a magnetic column paired with custom-made magnetic nanoparticles may hold a key to bringing immunotherapy into widespread and successful clinical use. A summary of the research, conducted in mouse and human cells, appears online July 14 in the journal ACS Nano.

The Johns Hopkins team focused on training and rapidly multiplying immune system white blood cells known as T cells because of their potential as an effective weapon against cancer, according to Jonathan Schneck, M.D., Ph.D., a professor of pathology, medicine and oncology at the Johns Hopkins University School of Medicine's Institute for Cell Engineering. "The challenge has been to train these cells efficiently enough, and get them to divide fast enough, that we could use them as the basis of a therapy for cancer patients. We've taken a big step toward solving that problem," he says.

In a bid to simplify and streamline immune cellular therapies, Schneck, Karlo Perica, a recent M.D./Ph.D. graduate who worked in Schneck's lab, and others worked with artificial white blood cells. These so-called artificial antigen-presenting cells (aAPCs) were pioneered by Schneck's lab and have shown promise in activating laboratory animals' immune systems to attack cancer cells.

To do that, Perica explains, the aAPCs must interact with naive T cells already present in the body, awaiting instructions about which specific invader to target and battle. The aAPCs bind to specialized receptors on the T cells' surfaces and "present" them with distinctive proteins called antigens. This process activates the T cells to ward off a virus, bacteria or tumor, as well as to make more T cells.

In a previous study in mice, Schneck's team found that naive T-cells activated more effectively when multiple aAPCs bound to different receptors on the cells, and then were exposed to a magnetic field. The magnets brought the aAPCs and their receptors closer together, priming the T cells both to battle the target cancer and divide to form more activated cells.

But naive T cells are as rare in the blood as a "needle in a haystack," Perica says. Because the ultimate goal is to harvest a patient's T cells from a blood sample, then train them and expand their numbers before putting them back into the patient, Schneck's research team looked to magnets as a potential way to separate the naive T cells from others in the blood.

The team mixed blood plasma from mice and, separately, humans with magnetic aAPCs bearing antigens from tumors. They then ran the plasma through a magnetic column. The tumor-fighting T cells bound to aAPCs and stuck to the sides of the column, while other cells washed straight through and were discarded. The magnetic field of the column activated the T cells, which were then washed off into a nourishing broth, or culture, to grow and divide. After one week, their numbers had expanded by an estimated 5,000 to 10,000 times. Because numbers of these cells could be expanded quickly enough to be therapeutically useful, the approach could open the door to individualized immunotherapy treatments that rely on a patient's own cells, says Perica.

Schneck says that the use of naive T cells could make the new technique useful for more patients than another immunotherapy now being tested, which relies on other white blood cells called tumor-infiltrating lymphocytes. Those cells are already "trained" to fight cancer, and researchers have shown some success isolating some of the cells from tumors, inducing them to divide, and then transferring them back into patients. But, Schneck says, not all patients are eligible for this therapy, because not all have tumor-infiltrating lymphocytes. By contrast, all people have naive T cells, so patients with cancer could potentially benefit from the new approach whether or not they have tumor-infiltrating lymphocytes.

"The aAPCs and magnetic column together provide the foundation for simplifying and streamlining the process of generating tumor-specific T cells for use in immunotherapy," says Juan Carlos Varela, M.D., Ph.D., a former member of Schneck's laboratory who is now an assistant professor at the Medical University of South Carolina.

The researchers found that the technique also worked with a mixture of aAPCs bearing multiple antigens, which they say could help combat the problem of tumors mutating to evade the body's defenses. "We get multiple shots on the goal," Schneck says.

While the team initially tested the new method only on cancer antigens, Schneck says it could also potentially work for therapies against chronic infectious diseases, such as HIV. He says that if further testing goes well, clinical trials of the technique could begin within a year and a half.

Source:

Johns Hopkins Medicine

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por cyto às 22:49

Terça-feira, 21.07.15

Scientists elucidate which mechanisms block natural killer cells and how this could be lifted

 

Scientists elucidate which mechanisms block natural killer cells and how this could be lifted

Published on July 8, 2015 at 12:00 PM 

Natural killer cells of the immune system can fend off malignant lymphoma cells and thus are considered a promising therapeutic approach. However, in the direct vicinity of the tumor they lose their effect. Scientists of Helmholtz Zentrum München have now elucidated which mechanisms block the natural killer cells and how this blockade could be lifted. The results were recently published in the European Journal of Immunology.

Natural killer cells (NK cells) are part of the immune system and provide an innate immunity against exogenous and altered endogenous structures. This also appears to apply to tumor cells, against which the body could develop immunity as it does against pathogens, e.g. against viruses. Tumors of the lymph nodes, called lymphomas, are malignant neoplasms that originate from the B cells or T cells of the lymphatic system. B cell lymphomas are very difficult to treat - which is why innovative approaches to therapy are needed. Earlier studies have shown that NK cells have the potential to attack B lymphoma cells and are therefore considered a possible approach to new treatment strategies. In the living organism, however, tumor control by NK cells has been found to be clearly limited.

NK cells become functionally impaired in the tumor microenvironment

In their experiments, the team led by Prof. Dr. Ralph Mocikat of the Institute of Molecular Immunology (IMI) at Helmholtz Zentrum München, found that the NK cells in the immediate vicinity of the tumor showed reduced function. If the cells were placed in a normal environment, their function could be restored within a few hours. This suggests that the factors responsible for the inactivation of the NK cells derive from the tumor itself.

An inflammatory cytokine inactivates NK cells - altered surface molecules block immune activation

The scientists engaged in the research project identified two important tumor-specific factors that are associated with impaired NK cell function. First, a specific inflammatory cytokine (IL-10) is indirectly involved in the inactivation of NK cells. Second, the tumor cells develop protective mechanisms against the NK cells. Thus, the research group showed that specific surface molecules of the tumor cells (NKG2D ligands) which NK cells could bind are down-regulated. Consequently, the NK cells lack an important activation mechanism and are no longer able to carry out cytotoxic activity. Despite the inhibitory strategies of the tumor cells, at an early stage the NK cells produce the cytokine interferon-gamma (IFN-γ), the scientists reported. IFN-γ is essential to activate further immune responses that support the fight against the tumor.

Immunotherapy possible using NK cells - with optimization potential

"Our results show that the transfer of NK cells is a possible strategic option to treat B cell lymphoma. According to our findings, this therapeutic approach can be optimized when transferred NK cells are already activated in vitro prior to their injection, thus bypassing the missing activation potential in the tumor microenvironment. An additional injection of IFN-γ or of antibodies against IL-10 could further support the immune activity," said study leader Mocikat.

Source:

Helmholtz Zentrum München - German Research Center for Environmental Health

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por cyto às 18:20

Terça-feira, 21.07.15

Ludwig, CRI launch clinical trials to evaluate immunotherapies for treatment of GBM and solid tumors

 

Ludwig, CRI launch clinical trials to evaluate immunotherapies for treatment of GBM and solid tumors

Published on July 8, 2015 at 11:50 PM 

Ludwig Cancer Research (Ludwig) and the Cancer Research Institute (CRI) have launched clinical trials evaluating an immunotherapy for the treatment of the brain cancer glioblastoma multiforme (GBM), and a combination of immunotherapies for a variety of solid tumors.

The trials are being conducted through the CVC Clinical Trials Network in collaboration with MedImmune, the global biologics research and development arm of AstraZeneca. The CVC Clinical Trials Network -- jointly managed by Ludwig and CRI -- is a coordinated global network of basic and clinical immunologists with expertise in devising and developing immunotherapies for the treatment of cancer. The CVC Clinical Trials Network is led by Jedd Wolchok, Ludwig member and director of the Ludwig Collaborative Laboratory at Memorial Sloan Kettering Cancer Center, as well as associate director of the CRI Scientific Advisory Council.

The GBM trial is a nonrandomized, multicenter Phase 2 trial testing the effects of MedImmune's checkpoint blockade antibody durvalumab (MEDI4736) in patients with GBM, which is the most aggressive and deadly type of adult brain cancer. The study will be conducted using three cohorts of patients - newly diagnosed, recurrent patients and those with tumors which have become unresponsive to standard treatment of care.

"GBM is an inevitably lethal cancer that has so far eluded every therapy in the pharmaceutical arsenal," said Jonathan Skipper, Ludwig's executive director of technology development. "We are hopeful that adding a promising immunotherapy to the treatment regimen for this brain cancer will yield significant benefits for patients who today have a median life expectancy of roughly 15 months, even with the best treatment available."

Durvalumab is an investigational human monoclonal antibody directed against programmed cell death ligand 1 (PD-L1). Signals from PD-L1 help tumors avoid detection by the immune system. Durvalumab blocks these signals, countering the tumor's immune-evading tactics. The antibody belongs to an emerging class of immunotherapies commonly referred to as checkpoint inhibitors because they remove checks the body places on immune activation.

"Checkpoint inhibitors have deservedly stirred considerable excitement in the oncology community as their application yields notable results against a growing variety of cancers," said Adam Kolom, managing director of CRI's venture fund and Clinical Accelerator, which organizes and provides philanthropic funding and clinical resources for this and other promising immunotherapy trials. "This will be the first time the immunotherapeutic agent will be tested against this difficult-to-treat cancer, and its outcomes are eagerly anticipated by the GBM patient community."

The other trial, which Ludwig and CRI launched in 2013, is a Phase 1 nonrandomized multicenter trial evaluating the combination of durvalumab with another checkpoint blockade therapy (tremelimumab, anti-CTLA-4) for the treatment of a variety of advanced solid tumors including ovarian cancer, non-small cell lung cancer, colorectal cancer, head and neck cancer, cervical cancer and kidney cancer.

Both clinical trials, which are now under way, are part of a larger clinical research program supported by Ludwig and CRI to speed the evaluation of novel cancer immunotherapies, alone or in combination with other cancer drugs. All of the studies will include collection of genetic and immunologic data derived from clinical samples obtained from patients. Such information will provide clues to the impact of the evaluated therapies and suggest refined or new strategies for treating cancer.

Source:

Ludwig Institute for Cancer Research

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por cyto às 18:12

Terça-feira, 21.07.15

Patients' own genetically engineered immune cells show significant success against multiple myeloma

 

Patients' own genetically engineered immune cells show significant success against multiple myeloma

Published on July 21, 2015 at 2:37 AM 

In recent years, immunotherapy has emerged as a promising treatment for certain cancers. Now this strategy, which uses patients' own immune cells, genetically engineered to target tumors, has shown significant success against multiple myeloma, a cancer of the plasma cells that is largely incurable. The results appeared in a study published online today in Nature Medicine.

Patients received an infusion of altered immune cells known as T-cells - roughly 2.4 billion of them - after undergoing a stem cell transplantation of their own stem cells. In 16 of 20 patients with advanced disease, there was a significant clinical response. The scientists found that the T-cell therapy was generally well-tolerated and that modified immune cells traveled to the bone marrow, where myeloma tumors typically are found, and showed a long-term ability to fight the tumors. Relapse was generally associated with a loss of the engineered T-cells.

"This study suggests that treatment with engineered T-cells is not only safe but of potential clinical benefit to patients with certain types of aggressive multiple myeloma," says first author Aaron P. Rapoport, MD, the Gary Jobson Professor in Medical Oncology at the University of Maryland School of Medicine. "Our findings provide a strong foundation for further research in the field of cellular immunotherapy for myeloma to help achieve even better results for our patients."

The trial is the first published use of genetically modified T-cells for treating patients with multiple myeloma. The approach has been used to treat leukemia as well as lymphoma, according to Dr. Rapoport, who is the Director of the Blood and Marrow Transplant Program at the University of Maryland Marlene and Stewart Greenebaum Cancer Center.

More than 77,000 people in the United States have multiple myeloma, with about 24,000 new cases diagnosed each year. Patients are treated with chemotherapy and in many cases an autologous stem cell transplant, but long-term response rates are low, and median survival is three to five years.

"The majority of patients who participated in this trial had a meaningful degree of clinical benefit," Dr. Rapoport notes. "Even patients who later relapsed after achieving a complete response to treatment or didn't have a complete response had periods of disease control that I believe they would not have otherwise experienced. Some patients are still in remission after nearly three years."

The research is a collaboration between the University of Maryland School of Medicine, the Perelman School of Medicine at the University of Pennsylvania and Adaptimmune, a clinical stage biopharmaceutical company which owns the core T-cell receptor technology and funded the study. Dr. Rapoport and co-authors Edward A. Stadtmauer, MD, of the University of Pennsylvania Abramson Cancer Center, and Gwendolyn K. Binder-Scholl, PhD, of Adaptimmune, contributed equally to the research. Dr. Rapoport is the study's principal investigator.

In the clinical study, patients' T-cells were engineered to express an affinity-enhanced T-cell receptor (TCR) specific for a type of tumor antigen, or protein, known as a cancer-testis antigen (CT antigen). The target CT antigens were NY-ESO-1 and LAGE-1. Up to 60 percent of advanced myelomas have been reported to express NY-ESO-1 and/or LAGE-1, which correlates to tumor proliferation and poorer outcomes. According to Adaptimmune, the trial is the first published study of lentiviral vector mediated TCR gene expression in humans.

Of the 20 patients treated, 14 (70 percent) had a near complete or complete response three months after treatment. Median progression-free survival was 19.1 months and overall survival was 32.1 months. Two patients had a very good partial response three months post treatment. Half the patients were treated at the University of Maryland Greenebaum Cancer Center and half at the University of Pennsylvania Abramson Cancer Center. Researchers note that the response rate was better than would be expected for a standard autologous stem cell transplant. In addition, patients did not experience side effects which have been associated with another type of genetically engineered T-cells (chimeric antigen receptors, or CARS) used to treat other cancers.

The study was originally developed by Carl H. June, MD, of the University of Pennsylvania Abramson Cancer Center, and Dr. Rapoport, who have been research collaborators for 18 years.

"Multiple myeloma is a treatable but largely incurable cancer. This study reveals the promise that immunotherapy with genetically engineered T-cells holds for boosting the body's ability to attack the cancer and provide patients with better treatments and control of their disease," says E. Albert Reece, MD., PhD, MBA, vice president for medical affairs at the University of Maryland and the John Z. and Akiko K. Bowers Distinguished Professor and dean of the University of Maryland School of Medicine. "This trial is also an excellent example of significant scientific advances that result from collaborations between academic medical institutions and private industry."

Source:

University of Maryland Medical Center

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por cyto às 18:10

Terça-feira, 21.07.15

Single molecule appears to be central regulator driving cancer metastasis

 

Single molecule appears to be central regulator driving cancer metastasis

Published on July 14, 2015 at 6:21 AM · 

Cancer is a disease of cell growth, but most tumors only become lethal once they metastasize or spread from their first location to sites throughout the body. For the first time, researchers at Thomas Jefferson University in Philadelphia report a single molecule that appears to be the central regulator driving metastasis in prostate cancer. The study, published online July 13th in Cancer Cell, offers a target for the development of a drug that could prevent metastasis in prostate cancer, and possibly other cancers as well.

"Finding a way to halt or prevent cancer metastasis has proven elusive. We discovered that a molecule called DNA-PKcs could give us a means of knocking out major pathways that control metastasis before it begins," says Karen Knudsen, Ph.D., Director of the Sidney Kimmel Cancer Center at Thomas Jefferson University, the Hilary Koprowski Professor and Chair of Cancer Biology, Professor of Urology, Radiation Oncology, and Medical Oncology at Jefferson.

Metastasis is thought of as the last stage of cancer. The tumor undergoes a number of changes to its DNA - mutations - that make the cells more mobile, able to enter the bloodstream, and then also sticky enough to anchor down in a new location, such as the bone, the lungs, the liver or other organs, where new tumors start to grow. Although these processes are fairly well characterized, there appeared to be many non-overlapping pathways that ultimately lead to these traits.

Now, Dr. Knudsen and colleagues have shown that one molecule appears to be central to many of the processes required for a cancer to spread. That molecule is a DNA repair kinase called DNA-PKcs. The kinase rejoins broken or mutated DNA strands in a cancer cell, acting as a glue to the many broken pieces of DNA and keeping alive a cell that should normally self-destruct. In fact, previous studies had shown that DNA-PKcs was linked to treatment resistance in prostate cancer, in part because it would repair the usually lethal damage to tumors caused by radiation therapy and other treatments. Importantly, Dr. Knudsen's work showed that DNA-PKcs has other, far-reaching roles in cancer.

The researchers showed that DNA-PKcs also appears act as a master regulator of signaling networks that turn on the entire program of metastatic processes. Specifically, the DNA-PKcs modulates the Rho/Rac enzyme, which allows many cancer cell types to become mobile, as well as a number of other gene networks involved in other steps in the metastatic cascade, such as cell migration and invasion.

In addition to experiments in prostate cancer cell lines, Dr. Knudsen and colleagues also showed that in mice carrying human models of prostate cancer, they could block the development of metastases by using agents that suppress DNA-PKcs production or function. And in mice with aggressive human tumors, an inhibitor of DNA-PKcs reduced overall tumor burden in metastatic sites.

In a final analysis that demonstrated the importance of DNA-PKcs in human disease, the researchers analyzed 232 samples from prostate cancer patients for the amount of DNA-PKcs those cells contained and compared those levels to the patients' medical records. They saw that a spike in the kinase levels was a strong predictor of developing metastases and poor outcomes in prostate cancer. They also showed that DNA-PKcs was much more active in human samples of castrate-resistant prostate cancer, an aggressive and treatment-resistant form of the disease.

"These results strongly suggest that DNA-PKcs is a master regulator of the pathways and signals that lead to the development of metastases in prostate cancer, and that high levels of DNA-PKcs could predict which early stage tumors may go on to metastasize," says Dr. Knudsen.

"The finding that DNA-PKcs is a likely driver of lethal disease states was unexpected, and the discovery was made possible by key collaborations across academia and industry," explains Dr. Knudsen. Key collaborators on the study, in addition to leaders of the Sidney Kimmel Cancer Center's Prostate Program, included the laboratories of Felix Feng (University of Michigan), Scott Tomlins (University of Michigan), Owen Witte (UCLA), Cory Abate-Shen (Columbia University), Nima Sharifi (Cleveland Clinic) and Jeffrey Karnes (Mayo Clinic), and contributions from GenomeDx.

Although not all molecules are easily turned into drugs, at least one pharma company has already developed a drug that inhibits DNA-PKcs, and is currently testing it in a phase 1 study (NCT01353625). "We are enthusiastic about the next step of clinical assessment for testing DNA-PKcs inhibitors in the clinic. A new trial will commence shortly using the Celgene CC-115 DNA-PKcs inhibitor. This new trial will be for patients advancing on standard of care therapies, and will be available at multiple centers connected through the Prostate Cancer Clinical Trials Consortium, of which we are a member," explained Dr. Knudsen.

"Although the pathway to drug approval can take many years, this new trial will provide some insight into the effect of DNAP-PKcs inhibitors as anti-tumor agents. In parallel, using this kinase as a marker of severe disease may also help identify patients whose tumors will develop into aggressive metastatic disease, so that we can treat them with more aggressive therapy earlier," says Dr. Knudsen. "Given the role of DNA-PKcs in DNA repair as well as control of tumor metastasis, there will be challenges in clinical implementation, but this discovery unveils new opportunities for preventing or treating advanced disease."

Source:

Thomas Jefferson University

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por cyto às 18:05

Sábado, 04.07.15

way to stop growth of cancer cells by targeting the Warburg Effect

SLU researchers find way to stop growth of cancer cells by targeting the Warburg Effect

Published on June 26, 2015 at 10:55 PM 

In research published in Cancer Cell, Thomas Burris, Ph.D., chair of pharmacology and physiology at Saint Louis University, has, for the first time, found a way to stop cancer cell growth by targeting the Warburg Effect, a trait of cancer cell metabolism that scientists have been eager to exploit.

Unlike recent advances in personalized medicine that focus on specific genetic mutations associated with different types of cancer, this research targets a broad principle that applies to almost every kind of cancer: its energy source.

The Saint Louis University study, which was conducted in animal models and in human tumor cells in the lab, showed that a drug developed by Burris and colleagues at Scripps Research Institute can stop cancer cells without causing damage to healthy cells or leading to other severe side effects.

The Warburg Effect

Metabolism -- the ability to use energy -- is a feature of all living things. Cancer cells aggressively ramp up this process, allowing mutated cells to grow unchecked at the expense of surrounding tissue.

"Targeting cancer metabolism has become a hot area over the past few years, though the idea is not new," Burris said.

Since the early 1900s, scientists have known that cancer cells prefer to use glucose as fuel even if they have plenty of other resources available. In fact, this is how doctors use PET (positron emission tomography) scan images to spot tumors. PET scans highlight the glucose that cancer cells have accumulated.

This preference for using glucose as fuel is called the Warburg effect, or glycolysis.

In his paper, Burris reports that the Warburg effect is the metabolic foundation of oncogenic (cancer gene) growth, tumor progression and metastasis as well as tumor resistance to treatment.

Cancer's goal: to grow and divide

Cancer cells have one goal: to grow and divide as quickly as possible. And, while there are a number of possible molecular pathways a cell could use to find food, cancer cells have a set of preferred pathways.

"In fact, they are addicted to certain pathways," Burris said. "They need tools to grow fast and that means they need to have all of the parts for new cells and they need new energy."

"Cancer cells look for metabolic pathways to find the parts to grow and divide. If they don't have the parts, they just die," said Burris. "The Warburg effect ramps up energy use in the form of glucose to make chemicals required for rapid growth and cancer cells also ramp up another process, lipogenesis, that lets them make their own fats that they need to rapidly grow."

If the Warburg effect and lipogenesis are key metabolic pathways that drive cancer progression, growth, survival, immune evasion, resistance to treatment and disease recurrence, then, Burris hypothesizes, targeting glycolysis and lipogenesis could offer a way to stop a broad range of cancers.

Cutting off the energy supply

Burris and his colleagues created a class of compounds that affect a receptor that regulates fat synthesis. The new compound, SR9243, which started as an anti-cholesterol drug candidate, turns down fat synthesis so that cells can't produce their own fat. This also impacts the Warburg pathway, turning cancer cells into more normal cells. SR9243 suppresses abnormal glucose consumption and cuts off cancer cells' energy supply.

When cancer cells don't get the parts they need to reproduce through glucose or fat, they simply die.

Because the Warburg effect is not a feature of normal cells and because most normal cells can acquire fat from outside, SR9243 only kills cancer cells and remains non-toxic to healthy cells.

The drug also has a good safety profile; it is effective without causing weight loss, liver toxicity, or inflammation.

Promising Results So far, SR9243 has been tested in cultured cancer cells and in human tumor cells grown in animal models. Because the Warburg pathway is a feature of almost every kind of cancer, researchers are testing it on a number of different cancer models.

"It works in a wide range of cancers both in culture and in human tumors developing in animal models," Burris said. "Some are more sensitive to it than others. In several of these pathways, cells had been reprogramed by cancer to support cancer cell growth. This returns the metabolism to that of more normal cells."

In human tumors grown in animal models, Burris said, "It worked very well on lung, prostate, and colorectal cancers, and it worked to a lesser degree in ovarian and pancreatic cancers."

It also seems to work on glioblastoma, an extremely difficult to treat form of brain cancer, though it isn't able to cross the brain/blood barrier very effectively. The challenge for researchers in this scenario will be to find a way to allow the drug to cross this barrier, the body's natural protection for the brain, which can make it difficult for drug treatments to reach their target.

And, in even more promising news, it appears that when SR9243 is used in combination with existing chemotherapy drugs, it increases their effectiveness, in a mechanism apart from SR9243's own cancer fighting ability.

Source:

Saint Louis University

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por cyto às 11:25

Sábado, 04.07.15

Nanoparticles packed with chemotherapy drug and coated with chitosan target cancer stem-like cells

 

Nanoparticles packed with chemotherapy drug and coated with chitosan target cancer stem-like cells

Published on July 1, 2015 at 7:35 AM ·

Nanoparticles packed with a clinically used chemotherapy drug and coated with an oligosaccharide derived from the carapace of crustaceans might effectively target and kill cancer stem-like cells, according to a recent study led by researchers at The Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC - James). Cancer stem-like cells have characteristics of stem cells and are present in very low numbers in tumors. They are highly resistant to chemotherapy and radiation and are believed to play an important role in tumor recurrence. This laboratory and animal study showed that nanoparticles coated with the oligosaccharide called chitosan and encapsulating the chemotherapy drug doxorubicin can target and kill cancer stem-like cells six times more effectively than free doxorubicin.

"Our findings indicate that this nanoparticle delivery system increases the cytotoxicity of doxorubicin with no evidence of systemic toxic side effects in our animal model," says principal investigator Xiaoming (Shawn) He, PhD, associate professor of Biomedical Engineering and a member of the OSUCCC - James Translational Therapeutics Program.

"We believe that chitosan-decorated nanoparticles could also encapsulate other types of chemotherapy and be used to treat many types of cancer."

This study showed that chitosan binds with a receptor on cancer stem-like cells called CD44, enabling the nanoparticles to target the malignant stem-like cells in a tumor.

The nanoparticles were engineered to shrink, break open, and release the anticancer drug under the acidic conditions of the tumor microenvironment and in tumor-cell endosomes and lysosomes, which cells use to digest nutrients acquired from their microenvironment.

He and his colleagues conducted the study using models called 3D mammary tumor spheroids (i.e., mammospheres) and an animal model of human breast cancer.

The study also found that although the drug-carrying nanoparticles could bind to the variant CD44 receptors on cancerous mammosphere cells, they did not bind well to the CD44 receptors that were overexpressed on noncancerous stem cells.

Source:

Ohio State University Wexner Medical Center

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por cyto às 11:21

Sexta-feira, 26.06.15

Vaxon Biotech receives new patent in Japan for cancer vaccine candidates

Vaxon Biotech receives new patent in Japan for cancer vaccine candidates

Published on June 22, 2015 at 9:21 AM ·

The company’s worldwide cancer vaccines patent portfolio, made up of ten patent families, now comprises 24 issued patents

Vaxon Biotech, a company specialized in anti-tumor immunotherapy, today announces that it has been granted a new patent in Japan. This patent (JP application n°2012-502822) covers a series of optimized cryptic peptides to be used in the design of the Vbx-026, a new cancer vaccine for solid tumors.

This patent gives Vaxon exclusive rights in Japan and raises its worldwide portfolio to 24 issued patents.

The patent will support the development of Vbx-026, a vaccine dedicated to the treatment of cancer patients expressing the HLA-A24 molecule. This molecule is widely expressed in the Asian population, mainly in Japan, with more than 40% of the Japanese population expressing HLA-A24. The initiation of preclinical development of the Vbx-026 vaccine is planned for 2016.

“This new patent will strengthen our position in Japan, a promising market for the development of the Vbx-026 vaccine,” said Dr. Kostas Kosmatopoulos, CEO of Vaxon Biotech. “With four cancer vaccines under development, ranging from lead optimization to phase II, we have built a strong patent portfolio and we now cover the three major HLA molecules, corresponding to around 80% of cancer patients.”

Vaxon Biotech develops therapeutic vaccines against cancer, based on its proprietary technology of optimized cryptic peptides, which are protected by ten patent families. All vaccines developed by Vaxon target universal tumor antigens and therefore have wide-ranging applications in cancer treatment.

Vx-001 and Vx-006 are already in clinical trials (Vx-001 in an ongoing randomized phase II trial in eight European countries and Vx-006 in an ongoing phase I trial). Vbx-016 has successfully completed its preclinical development and is ready to enter clinical trials and Vbx-026 is at the final stage of lead optimization.

Vx-001 and Vx-006 can be used for the treatment of patients expressing HLA-A2, the most common HLA molecule in humans (40-45% of the world population). Vx-001 and Vx-006 are fully protected by a total of 17 patents granted in Europe, the US, Canada, China and Japan. These patents belong to four patent families and cover peptide optimization technology, the products derived from this technology and their use. Six of these patents belong to INSERM/IGR and have been licensed to Vaxon Biotech, while the remaining 11 are Vaxon’s own property.

Vbx-016 can be used for the treatment of patients expressing HLA-B7, a common HLA molecule (25% of the population). Vbx-016 is already protected by three patent families. Five patents are already granted in Europe, the US, China and South Korea. Additional patents are still under review. All these patents are Vaxon’s own property.

The global market for cancer vaccines is expected to grow to $4.3 billion (€3.8 billion) by 2019, with a five-year compound annual growth rate (CAGR) of 1.3%. Technological advancements, new product launches and unmet treatment needs are predicted to drive consistent growth in this market for the foreseeable future.

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por cyto às 00:58

Terça-feira, 23.06.15

NW Bio releases promising new data on DCVax-Direct Phase I trial for inoperable solid tumors

NW Bio releases promising new data on DCVax-Direct Phase I trial for inoperable solid tumors

Published on June 2, 2015 at 10:00 AM · 

Northwest Biotherapeutics (NASDAQ: NWBO) ("NW Bio"), a U.S. biotechnology company developing DCVax® personalized immune therapies for solid tumor cancers, over the weekend in Chicago released promising new data on their Phase I trial of DCVax-Direct for direct injection into all types of inoperable solid tumors.

The patients enrolled in the trial had late stage cancers, with an average of three inoperable tumors. The patients had failed multiple prior therapies and had a poor prognosis.

The trial enrolled 40 patients, and 39 were evaluable. A conservative treatment regimen was used. Although the patients had multiple inoperable tumors, only 1 tumor was injected with DCVax-Direct. The treatments included only 3 injections in the first 2 weeks (Day 0, 7 and 14), and up to 3 additional injections spaced months apart thereafter (Weeks 8, 16 and 32), over a total period of 8 months.

Patients typically received their first injection about 1-1/2 months after recruitment. Four patients are still in the process of completing the study visits, and data collection is ongoing on all of the patients.

The trial tested three different dose levels of DCVax-Direct, two different methods of activating the dendritic cells that comprise DCVax-Direct, and a dozen different cancers. Findings to date include encouraging survival data and substantial induction of immune checkpoint expression (PDL-1).

The webcast and presentation by Dr. Bosch can be found on the Company's website at nwbio.com/webcast

Findings to date include the following:

  • 27 of 39 patients are still alive at up to 18 months after first injection.
  • Patient survival correlates with the method of dendritic cell activation used. With the preferred method, 18 of 21 patients are still alive.
  • Treatment effects have been observed in diverse cancers, including lung, breast, colorectal, pancreatic, sarcoma, melanoma, neuro-endocrine and other cancers.
  • Patient survival correlates with the number of DCVax-Direct injections.
  • Patient survival also correlates with stabilization of disease at Week 8 (4th injection visit). Among patients treated with the preferred method of dendritic cell activation, 16 of 19 achieved stable disease (i.e., less than 25% increase in tumor size from baseline) at Week 8.

Findings to date relating to immunological responses include the following:

  • Induction of PDL-1 immune checkpoint expression was seen in 64% of evaluable patients (14 of 22) following DCVax-Direct treatment. This suggests that the tumors are putting up defenses against the immune responses induced by DCVax-Direct, and marks these patients as potential candidates for treatment with checkpoint inhibitor therapies.
  • An increase in T-cell infiltration into tumors, by functionally active T-cells, was seen following DCVax-Direct treatment.
  • Both local effects (in the injected tumor) and systemic effects were observed.

Based on the findings from the Phase I trial, the Company plans to enhance its Phase II trials in several ways, including by:

  • Using only the preferred activation method of the DCVax dendritic cells.
  • Injecting multiple inoperable tumors at each treatment visit, not just one.
  • Providing more frequent treatments and a larger total number of treatments.

The Company plans to pursue Phase II trials in non-small cell lung cancer and sarcoma, as well as a Phase II trial for multiple diverse types of cancers similar to the Phase I study. The Company also plans to expand the trial sites to include countries beyond the U.S.

"We are quite encouraged to see these results across diverse types of cancers, in late stage patients with multiple inoperable tumors who have exhausted other treatment options, and with quite a conservative DCVax-Direct treatment regimen," commented Linda Powers, CEO of NW Bio. "We are looking forward to proceeding with Phase II trials applying the lessons learned from this informative Phase I trial."

Source:

Northwest Biotherapeutics, Inc.

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por cyto às 17:20


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