Researchers in Russia have reported that three specific bacteria are linked to better outcomes in melanoma when patients undergo immunotherapy. The information came from the press service of the Russian Science Foundation (RNF).
Immunotherapy stands as one of the most hopeful approaches in cancer treatment. It leverages the body’s own defenses, activating immune responses through targeted drugs to fight tumors. Compared with chemotherapy or radiotherapy, immunotherapy generally causes fewer and less severe side effects. Yet its effectiveness is not guaranteed for every patient. A key challenge is that cancer cells can undermine the immune attack by manipulating immune checkpoints. These checkpoints are molecules on the surface of cells that communicate with immune cells, sometimes convincing them that a cancer cell is a friendly target. To counter this, doctors can block these checkpoints with specialized inhibitors, but such treatments often come with a spectrum of side effects. Many of these adverse effects are thought to be tied to individual variations in the gut microbiome. This area of study has opened new possibilities for personalizing cancer therapy by considering microbiome health as part of the treatment plan.
University researchers from the Yu M. Lopukhin Federal Scientific and Clinical Center for Physical and Chemical Medicine and collaborators from other institutions carried out a genetic analysis of stool samples from 449 volunteers receiving immunotherapy for melanoma. They then compared the microbiome profiles with treatment outcomes. The team reported that three bacterial types correlated with successful immunotherapy in about 85 percent of cases. One of these is a member of the bifidobacteria group, commonly found in dairy products and widely used in probiotic supplements. The researchers suggest that, for patients facing melanoma, incorporating probiotics that support a healthy gut flora could enhance the effectiveness of immunotherapy. This finding has potential implications for clinical practice, guiding nutritional and microbial interventions alongside standard cancer care.
In addition, the scientists identified biomarkers that could help forecast how well a patient might respond to immunotherapy. They found certain bacterial genes present in stool samples that were associated with effective treatment. Patients whose metagenomes contained genes involved in the metabolism of bacterial polysaccharides, fatty acids, and other microbial compounds tended to respond better to therapy. Conversely, treatment effectiveness declined in those whose samples carried genes linked to pathogenic bacteria that can exhibit antibiotic resistance. These biomarkers offer a possible path toward predicting treatment success and tailoring regimens to individual microbiome profiles.
The researchers hope that their work will lead to safer and more effective cancer care by integrating microbiome-aware strategies into immunotherapy. By identifying beneficial bacterial signatures and relevant biomarkers, clinicians may optimize patient selection and supportive care, potentially reducing unnecessary side effects and improving overall outcomes. The findings underscore the growing interest in how microbial communities influence immune responses and cancer treatment, and they pave the way for future trials that combine microbiome modulation with immunotherapy.
In related science news, zoologists recently documented a curious behavior involving water spouting in a species of freshwater mussels, captured on video. These observations remind readers that the natural world continues to reveal unexpected phenomena alongside medical advances.