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Hello Health Rounds readers! The search for effective cancer vaccines has yielded only limited results, but an experimental vaccine tested against the most aggressive form of breast cancer shows promise. We also discuss a potentially cutting-edge laboratory breakthrough in gene therapy, as well as the quality-of-life benefits of preserving a critical nerve during surgery for breast cancer. stomach.
Triple-negative cancer vaccine shows promise in first trial
A small trial of an experimental vaccine has shown promising results for patients with the most aggressive type of breast cancer, according to a report published Thursday in Genome Medicine.
Eighteen patients recently diagnosed with triple-negative breast cancer that had not yet spread to other organs received three doses of the personalized vaccine after undergoing standard chemotherapy and surgery to remove the tumor.
Three years later, 16 patients were still cancer-free. The study did not include a control group, but the researchers note that with standard care, about half of the patients would not have had cancer after three years.
The vaccine is designed to target key genetic mutations in the patient’s tumor, called neoantigens, new proteins that have formed in cancer cells due to mutations in the tumor’s DNA.
The vaccines are also designed to train patients’ immune cells to recognize and attack any cells carrying these mutations.
As noted in another article published in the same journal (), researchers created software to identify the neoantigens most likely to trigger a strong immune response.
Small preliminary studies of this type are designed to test safety, not effectiveness. Still, the results “are better than we expected,” Dr. William Gillanders of Washington University School of Medicine in St. Louis, who led the trial, said in a statement.
louis, who led the trial, said in a statement: “We continue to pursue this vaccine strategy and are currently conducting randomized controlled trials that establish a direct comparison between standard treatment and a vaccine, on the one hand, and standard treatment alone, on the other hand, we are encouraged by what we are seeing in these patients so far.”
New method to replace important muscular dystrophy genes
In studies in mice, experimental technology delivered large, healthy genes to replace dysfunctional genes that cause debilitating muscular dystrophies, researchers reported Thursday in Science.
In muscular dystrophies and some other conditions, the genes responsible are extremely large. Current methods of introducing healthy genes to replace defective genes do not allow such large quantities of genetic material to be transferred into the body.
Elevidys, a gene therapy from Sarepta Therapeutics SRPT.O approved in the United States last year to treat young children with Duchenne muscular dystrophy, delivers a shortened version of the normal gene.
The new technology overcomes this obstacle by delivering the two halves of a gene separately. Once in the cell, the two segments come together.
RNA molecules called ribozymes act like scissors, cutting the gene in two, the researchers explain.
When ribozymes cut RNA, they leave ends that are recognized by the cell’s natural repair pathway, which is then able to put the pieces back together.
The researchers called this process “StitchR,” short for “stitch RNA.” According to the researchers, the stitched genes appear to behave essentially the same way as their full-length natural counterparts, efficiently translating genetic information into functional proteins.
In mice with muscular dystrophy, the treatment restored normal levels of important therapeutic muscle proteins, the researchers reported.
Specifically, StitchR restored the Dystrophin protein, absent in patients with Duchenne muscular dystrophy, and the Dysferlin protein, absent in individuals with a less common form of the disease, known as muscular dystrophy. type 2B/R2 belts.
There are more than 30 types of muscular dystrophies, all of which weaken muscles. Patients often lose the ability to walk, and the disease sometimes affects the heart and respiratory muscles.
“Through StitchR and other tools, we are working to develop treatments for some of the most debilitating genetic diseases on the planet, many of which currently have no treatment or cure,” said Douglas Anderson, director of the University of Rochester School of Medicine and Dentistry, in a press release.
His team plans to collaborate with other researchers to develop StitchR treatments for other diseases caused by large genes.
There are benefits to protecting a nerve during stomach surgery
Preserving an important nerve during surgery for early-stage stomach cancer can improve quality of life afterward, according to the results of a clinical trial.
The study involved 264 patients with early-stage stomach cancer who underwent surgery to remove the lower third of the stomach and reconnect the remaining part to the small intestine.
In half of the patients, surgeons did not cut the vagus nerve, which transmits signals between the brain and the digestive system. Electrophysiological methods and fluorescent dyes were used to monitor the vagus nerve during surgery to ensure it was not damaged, the surgeons said.
Intraoperative neurophysiological monitoring has been used for decades in thyroid and spine surgeries, but few studies have tested it for vagus nerve preservation, the researchers note.
One year after surgery, rates of weakening of the stomach muscles, or gastroparesis, meaning the stomach empties too slowly, were 0.8% in the group having benefited from preservation of the vagus nerve, compared to 7.6% in the group having undergone the usual surgical procedure.
Symptoms of gastroparesis may include bloating, nausea, vomiting, and abdominal pain.
The formation of gallstones, common after this type of intervention, occurred in 6.8% of the group that underwent the usual surgery, but not at all in the group that benefited from preservation of the vagus nerve.
Preservation surgery took longer, but there were no differences in complication rates or rates of cancer progression afterward, according to the report published in JAMA Surgery.
According to an international analysis carried out in 2020, gastric cancer is the fifth most common cancer worldwide and the third leading cause of cancer-related mortality.
