Tag Archives: tumor
Chinese researchers have developed biodegradable tumor-targeting nanoparticles, which provides a promising therapy for tumor treatment, according to the Chinese Academy of Sciences (CAS).
A joint research team with scientists from the CAS developed the tumor-targeting nanoparticles as a combination of tumor-infarction therapy and chemotherapy, said the CAS.
It has long been a challenge for researchers to find a safe and effective therapy for vascular thrombosis. Drugs that induce thrombosis in the tumor vasculature have not resulted in long-term tumor eradication.
The CAS research team developed the nanoparticle, a type of DNA nanorobot that can precisely send the thrombin to the tumor-vessel walls and the tumor stroma, leaving the tumor to “starve to death.”
Study results showed that the co-administration of a cytotoxic payload and a protease to elicit vascular infarction in tumors with biodegradable tumor-targeting nanoparticles represented a promising strategy for improving the therapeutic index of coagulation-based tumor therapy.
The study has been published online by the journal Nature Biomedical Engineering.
A drug that could stop cancer cells repairing themselves has shown early signs of working. More than half of the 40 patients given berzosertib had the growth of their tumours halted. Berzosertib was even more effective when given alongside chemotherapy, the trial run by the Institute of Cancer Research (ICR) and the Royal Marsden NHS Trust in UK suggested. The trial was designed to test the safety of the drug. The drug is the first to be trialled of a new family of treatments, which block a protein involved in DNA repair. Blocking this protein prevents cancers from mending damage to their cells. It’s part of a branch of treatment known as “precision medicine“, which targets specific genes or genetic changes.
The study involved patients with very advanced tumours, for whom no other treatment had worked. This was what is known as a “phase one” trial, which is only designed to test the safety of a treatment. But the ICR said the researchers did find some early indications that berzosertib could stop tumours growing. One of the study’s authors, Prof Chris Lord, a professor of cancer genomics at the ICR, said these early signs were “very promising”, adding that it was unusual in phase one trials to see a clinical response. Further trials will be needed to demonstrate the drug’s effectiveness, though.
“This study involved only small numbers of patients…Therefore, it is too early to consider berzosertib a game changer in cancer treatment,” said Dr Darius Widera at the University of Reading. “Nevertheless, the unusually strong effects of berzosertib, especially in combination with conventional chemotherapy, give reasons to be optimistic regarding the outcomes of follow-up studies.”
One patient in the trial, with advanced bowel cancer, had his tumours completely disappear after treatment with berzosertib, and has remained cancer-free for two years. Another, whose ovarian cancer returned following a different course of treatment, saw her tumours shrink after combination treatment with the drug and chemotherapy. Chemotherapy works by damaging cancer cells’ DNA, so using it in conjunction with this new treatment, which stops the cells from repairing themselves, appears to give an even greater benefit. And berzosertib is able to target tumour cells without affecting other healthy cells, Prof Lord said.
“Our new clinical trial is the first to test the safety of a brand-new family of targeted cancer drugs in people, and it’s encouraging to see some clinical responses even in at this early stage,” said Professor Johann de Bono, head of drug development at the ICR and the Royal Marsden.
Two newly published studies are presenting novel diagnostic techniques to help catch the most aggressive forms of prostate cancer at an early stage. A University of East Anglia study presents an innovative way to measure gene expression in tumor samples and predict disease severity, while an Australian study details a new kind of imaging technique promising to detect metastasized prostate cancer with greater accuracy than ever before.
Two new techniques are designed to detect aggressive forms of prostate cancer and catch it when it metastasizes
“Prostate cancer is the most common cancer in men in the UK,” explains Colin Cooper, lead researcher on a new study from the University of East Anglia. “It usually develops slowly and the majority of cancers will not require treatment in a man’s lifetime. However, doctors struggle to predict which tumors will become aggressive, making it hard to decide on treatment for many men.”
In order to develop a way for doctors to better identify the most aggressive tumors the researchers examined different gene expression patterns in nearly 2,000 prostate tumor samples. Applying a mathematical model called Latent Process Decomposition, the study homed in on a particular pattern of gene expression associated with the most aggressive clinical cases.
The pattern relates to a subtype of cells the team has labeled DESNT, and suggest the more tumor cells in a sample that are of that DESNT subtype, the faster a patient will progress through the disease. The hope is that this can act as a biomarker to stratify prostate cancer patients, identifying those needing more urgent invasive treatments.
“If you have a tumor that is majority DESNT you are more likely to get metastatic disease, in other words it is more likely to spread to other parts of your body,” says Daniel Brewer, co-lead researcher on the project. “This is a much better indication of aggressive disease.”
Identifying when prostate cancer has metastasized is obviously of vital importance in guiding treatment. A team of Australian researchers just published the results of a clinical trial evaluating the efficacy of a new imaging technique developed to provide detailed data on the spread of the disease.
“Around one in three prostate cancer patients will experience a disease relapse after surgery or radiotherapy,” says Declan Murphy, senior author on the new imaging study. “This is partly because current medical imaging techniques often fail to detect when the cancer has spread, which means some men are not given the additional treatments they need.”
Researchers at Mount Sinai have developed last year a novel approach to cancer immunotherapy, injecting immune stimulants directly into a tumor to teach the immune system to destroy it and other tumor cells throughout the body.
The “in situ vaccination” worked so well in patients with advanced-stage lymphoma that it is also undergoing trials in breast and head and neck cancer patients, according to a study published in Nature Medicine in April.
The treatment consists of administering a series of immune stimulants directly into one tumor site. The first stimulant recruits important immune cells called dendritic cells that act like generals of the immune army. The second stimulant activates the dendritic cells, which then instruct T cells, the immune system’s soldiers, to kill cancer cells and spare non-cancer cells. This immune army learns to recognize features of the tumor cells so it can seek them out and destroy them throughout the body, essentially turning the tumor into a cancer vaccine factory.
“The in situ vaccine approach has broad implications for multiple types of cancer,” said lead author Joshua Brody, MD, Director of the Lymphoma Immunotherapy Program at The Tisch Cancer Institute at the Icahn School of Medicine at Mount Sinai. “This method could also increase the success of other immunotherapies such as checkpoint blockade.”
After testing the lymphoma vaccine in the lab, it was tested in 11 patients in a clinical trial. Some patients had full remission from months to years. In lab tests in mice, the vaccine drastically increased the success of checkpoint blockade immunotherapy, the type of immunotherapy responsible for the complete remission of former President Jimmy Carter’s cancer and the focus of the 2018 Nobel Prize in Medicine.
Tumors are hogs, gobbling nutrients to fuel their runaway growth, and for decades researchers have tried to develop drugs that cut off their food supply. A study out today shows that an updated version of a failed cancer drug can not only prevent tumor cells from using an essential nutrient, but also spur immune cells to attack the growths.
“It’s a pretty striking paper,” says cancer biologist Ralph DeBerardinis of the University of Texas Southwestern Medical Center in Dallas, who wasn’t connected to the study. “With a single drug, you can in effect starve the tumor and beef up the immune cells.”
Cancer cells eat to obtain molecules vital for survival and replication, but their gluttony also turns their surroundings into an acidic, oxygen-deprived moat that stymies immune cells trying to eliminate them. One of the nutrients many tumors need in abundance is the amino acid glutamine, which provides the building blocks for fabricating molecules such as DNA, proteins, and lipids. “Glutamine is incredibly important for cellular metabolism,” says immunologist Jonathan Powell of the Johns Hopkins School of Medicine in Baltimore, Maryland.
Starting in the 1950s, researchers tried to turn tumors’ glutamine dependence against them, developing drugs to block its metabolism. A bacteria-derived compound called DON, for instance, kills tumors by inhibiting several enzymes that allow cancer cells to use glutamine. In clinical trials, however, the drug provoked severe nausea and vomiting, and it was never approved.
Now, Powell and colleagues have crafted a new version of DON that may be easier to stomach. It carries two chemical groups that keep it inert until it reaches the tumor’s neighborhood. There, enzymes that normally loiter around tumors remove these molecular handcuffs, unleashing the drug on the cancerous cells. With this approach, “the vast majority of the active drug is where we want,” Powell says.
To test their new compound, he and colleagues injected four types of cancer cells into mice, inducing tumors. They then dosed some of the animals with their next-generation DON. The drug worked against all four kinds of tumors, the scientists report today in Science. In untreated mice, for example, colon cancer tumors had grown more than five times larger after about 3 weeks. But in rodents that received DON, the tumors shrank and almost disappeared. The researchers found that the drug wasn’t just throttling glutamine metabolism. It was also disrupting other aspects of the cells’ biochemistry, such as their ability to use the sugar glucose.
There’s another reason to celebrate the gut microbiome—a healthy gut might actually be able to save lives. According to scientists at the Lawson Health Research Institute, all it takes to strengthen your immune system is to improve your gut health, a process that we know is as easy as increasing your ingestion of probiotics and dietary fiber. How’s that for functional food?
These Lawson Health Research Institute scientists are implementing a preliminary study that would discover whether a fecal transplant of a healthy microbiome can help patients with melanoma become more receptive to immunotherapy treatments. During immunotherapy treatments, patients take certain drugs to stimulate their immune systems in order to attack tumors in their bodies. A fecal transplant, according to these researchers, would make their immune systems more receptive to the drugs and, in turn, could help more people successfully fight their cancer.
“We know that some people’s immune systems don’t respond well, and it seems to be associated with the microbes within your gut,” Michael Silverman, M.D., a Lawson associate scientist, said in a video filmed by the research institute. “The goal is to give people healthy microbes to replenish the microbes in their gut so that their immune system responds optimally, and they’re able to control the tumor.”
Breast cancer is one of the most common cancers, and one of the leading causes of death in women globally. Breast cancer is a disease where cells located in the breast grow out of control. Although a majority of breast cancers are discovered in women at the age of 50 years or older, the disease can affect anyone, including men and younger women, according to the Centers for Disease Control and Prevention (CDC). Last year there were 9.6 million deaths and 18.1 million new cases of breast cancer diagnosed globally according to the latest report from the International Agency for Research on Cancer (IARC) released in September 2018.
In 2019 alone, the U.S. National Cancer Institute estimates that there will be 268,600 new female breast cancer cases and 41,760 fatalities. Earlier this month, researchers based in Switzerland published in Cell their study in using applied artificial intelligence (AI) machine learning to create a comprehensive tumor and immune atlas of breast cancer ecosystems that lays the foundation for innovative precision medicine and immunotherapy.
The study was led by professor Bernd Bodenmiller, Ph.D. at the Institute of Molecular Life Sciences at the University of Zurich in Switzerland. Bodenmiller is a recipient of the 2019 Friedrich Miescher Award, Switzerland’s highest distinction for outstanding achievements in biochemistry. His team worked in collaboration with the Systems Biology Group at IBM Research in Zurich led by María Rodríguez Martínez, Ph.D. with the shared goal to produce a foundation for more targeted breast cancer treatment through precision medicine.
A new immunotherapy screening prototype developed by University of California, Irvine (UCI) researchers can quickly create individualized cancer treatments that will allow physicians to effectively target tumors without the side effects of standard cancer drugs. UCI’s Weian Zhao and Nobel laureate David Baltimore with Caltech led the research team that developed a tracking and screening system that identifies T cell receptors with 100-percent specificity for individual tumors within just a few days.
In the human immune system, T cells have molecules on their surfaces that bind to antigens on the surface of foreign or cancer cells. To treat a tumor with T cell therapy, researchers must identify exactly which receptor molecules work against a specific tumor’s antigens. UCI researchers have sped up that identification process.
“This technology is particularly exciting because it dismantles major challenges in cancer treatments,” said Zhao, an associate professor of pharmaceutical sciences. “This use of droplet microfluidics screening significantly reduces the cost of making new cancer immunotherapies that are associated with less systemic side effects than standard chemotherapy drugs, and vastly speeds up the timeframe for treatment.”
Zhao added that traditional cancer treatments have offered a one-size-fits-all disease response, such as chemotherapy drugs which can involve systemic and serious side effects.
Research findings appear in Lab on a Chip.