Soon a Vaccine to Prevent Melanoma

A personalized “cancer vaccine” may help keep a deadly form of skin cancer from growing for years, a small new study in humans suggests. Unlike vaccines that prevent infections, such as measles and influenza, cancer vaccines are a form of immunotherapy that take down cancer cells that already exist. The vaccines train immune cells, called T cells, to better recognize cancer and target it for destruction, while sparing healthy cells in the body. For example, the new experimental vaccine works by training T cells to spot specific proteins on melanoma cells, a type of skin cancer. In the study, scientists found that the T cells continue to “remember” these proteins for at least four years after the vaccination — and they even learn to recognize more melanoma-related proteins over time.

The only way that could have happened is if there was actually killing of the tumor cells. And presumably it was the T cells induced by the vaccine that did that killing,” said study author Dr. Catherine Wu, a physician-scientist with the Dana-Farber Cancer Institute and Harvard Medical School in Boston and the Broad Institute in Cambridge, Massachusetts. That’s because, once killed, tumor cells fall apart and spill their contents; T cells then swoop in to examine these remains and log that information away for future attacks, Wu said.

While the results are promising, the new study only included eight patients, and more trials need to be conducted to pin down exactly how effective the vaccine is, she added. But as of now, the limited data hint that the vaccine triggers a persistent immune response and can help keep cancer under control, especially when combined with other immunotherapies, the authors noted. The new study, published Jan. 21 in the journal Nature Medicine, included patients with advanced melanoma who had recently undergone surgery for the cancer. The researchers took samples of the patients’ removed tumors and used them to craft personalized vaccines for each of the eight participants.

Source: https://www.realclearscience.com/

How To Strengthen Your Immune System

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.”

Source: https://www.mindbodygreen.com/

Injection Of Nanoparticle Effective Against Melanoma

Researchers at Tel Aviv University have developed a novel nano-vaccine for melanoma, the most aggressive type of skin cancer. Their innovative approach has so far proven effective in preventing the development of melanoma in mouse models and in treating primary tumors and metastases that result from melanoma. The focus of the research is on a nanoparticle that serves as the basis for the new vaccine. The study was led by Prof. Ronit Satchi-Fainaro, chair of the Department of Physiology and Pharmacology and head of the Laboratory for Cancer Research and Nanomedicine at TAU‘s Sackler Faculty of Medicine, and Prof. Helena Florindo of the University of Lisbon while on sabbatical at the Satchi-Fainaro lab at TAU. Melanoma develops in the skin cells that produce melanin or skin pigment.

The war against cancer in general, and melanoma in particular, has advanced over the years through a variety of treatment modalities, such as chemotherapy, radiation therapy and immunotherapy; but the vaccine approach, which has proven so effective against various viral diseases, has not materialized yet against cancer,” says Prof. Satchi-Fainaro. “In our study, we have shown for the first time that it is possible to produce an effective nano-vaccine against melanoma and to sensitize the immune system to immunotherapies.

The researchers harnessed tiny particles, about 170 nanometers in size, made of a biodegradable polymer. Within each particle, they “packed two peptides — short chains of amino acids, which are expressed in melanoma cells. They then injected the nanoparticles (or “nano-vaccines“) into a mouse model bearing melanoma. “The nanoparticles acted just like known vaccines for viral-borne diseases,” Prof. Satchi-Fainaro explains. “They stimulated the immune system of the mice, and the immune cells learned to identify and attack cells containing the two peptides — that is, the melanoma cells. This meant that, from now on, the immune system of the immunized mice will attack melanoma cells if and when they appear in the body.”

The results were published recently in Nature Nanotechnology.

Source: https://english.tau.ac.il/

Nanoparticle Targets Tumor-infiltrating Immune Cells, Flips Switch Telling Them To Fight

Immunotherapy’s promise in the fight against cancer drew international attention after two scientists won a Nobel Prize this year for unleashing the ability of the immune system to eliminate tumor cells.

But their approach, which keeps cancer cells from shutting off the immune system’s powerful T-cells before they can fight tumors, is just one way to use the body’s natural defenses against deadly disease. A team of Vanderbilt University bioengineers today announced a major breakthrough in another: penetrating tumor-infiltrating immune cells and flipping on a switch that tells them to start fighting. The team designed a nanoscale particle to do that and found early success using it on human melanoma tissue.

Tumors are pretty conniving and have evolved many ways to evade detection from our immune system,” said John T. Wilson, assistant professor of chemical and biomolecular engineering and biomedical engineering. “Our goal is to rearm the immune system with the tools it needs to destroy cancer cells. “Checkpoint blockade has been a major breakthrough, but despite the huge impact it continues to have, we also know that there are a lot of patients who don’t respond to these therapies. We’ve developed a nanoparticle to find tumors and deliver a specific type of molecule that’s produced naturally by our bodies to fight off cancer.

That molecule is called cGAMP, and it’s the primary way to switch on what’s known as the stimulator of interferon genes (STING) pathway: a natural mechanism the body uses to mount an immune response that can fight viruses or bacteria or clear out malignant cells. Wilson said his team’s nanoparticle delivers cGAMP in a way that jump-starts the immune response inside the tumor, resulting in the generation of T-cells that can destroy the tumor from the inside and also improve responses to checkpoint blockade.

While the Vanderbilt team’s research focused on melanoma, their work also indicates that this could impact treatment of many cancers, Wilson said, including breast, kidney, head and neck, neuroblastoma, colorectal and lung cancer.

The findings are reported in the journal Nature Nanotechnology.

Source: https://news.vanderbilt.edu/