A healthier gut may be key to cancer care
A Healthier Gut May Be Key to Cancer Care
A healthier gut may be key – In the early 1990s, Dr. Marcel van den Brink, a leading expert in bloodborne cancers such as leukemia, faced a critical challenge in his medical practice. Many of his patients endured complex procedures to restore their immune systems after devastating chemotherapy treatments. These procedures, known as allogenic hematopoietic cell transplants, involved eliminating the patient’s existing immune system to make way for donor cells. However, the transition period left patients highly susceptible to infections and other complications, with roughly a quarter of them succumbing to issues like graft-versus-host disease during that time.
Van den Brink and his colleagues began to realize that their aggressive treatments might be causing unintended harm. “We were causing a lot of collateral damage with our intense therapies,” he noted. This insight sparked a shift in medical research, focusing on the intricate relationship between gut microbiota and immune function. The discussion gained momentum recently when U.S. Health and Human Services Secretary Robert F. Kennedy Jr. attended a symposium at the City of Hope Cancer Center in Duarte, California, where van den Brink has served as president since 2023. During the event, Dr. Jay Bhattacharya, director of the National Institutes of Health, described the latest findings in microbiome research as “mind-blowing.” The symposium was titled “the next frontier of cancer prevention and care,” underscoring the growing importance of this field.
A recent publication by the American Society of Clinical Oncology highlights nearly 100 ongoing studies exploring how gut microbiota can be manipulated to enhance cancer treatment. These investigations have revealed that the microbiome plays a pivotal role in immunotherapy, a method that leverages the body’s own immune system to target cancer cells. Now, a groundbreaking trial is set to begin at the University Hospitals Seidman Cancer Center in Cleveland, where a kidney cancer patient will be the first to receive probiotics as part of a late-phase study. This trial, funded by the National Cancer Institute, will test CBM588, a strain of Clostridium butyricum bacteria, which is already a widely used dietary supplement in Japan for digestive health.
“We’re hoping to change the standard of care,” said Dr. Pedro Barata, one of the principal investigators in the Cleveland study. The trial aims to determine whether CBM588 can amplify the effectiveness of immunotherapy for patients with advanced renal cell carcinoma. Over the next few years, nearly 700 participants will take capsules of CBM588 alongside their standard treatments, marking a significant step in integrating microbiome-based therapies into oncology protocols.
The concept of using gut bacteria to influence disease outcomes has roots in unexpected places. Dr. Sumanta Pal, who led a key study at the City of Hope Cancer Center in Los Angeles, first became interested in this area over a decade ago. At the time, he was engaged in discussions with Dr. Paul Frankel, a biostatistician at the same facility. Frankel shared observations from the poultry industry, where farmers noticed that healthier animals often had more resilient gut bacteria. “If their chickens are [thriving and growing well], they’ll limit how often they clean the litter when introducing new stock,” Frankel explained. This correlation between microbiota and animal health inspired Pal to explore similar connections in human disease.
Further evidence emerged from livestock practices, where probiotics and prebiotics are routinely used to support gut health. For instance, pigs are often fed inulin, a fiber that acts as a prebiotic to encourage the growth of beneficial bacteria like Bifidobacteria. These real-world applications demonstrated that manipulating the microbiome could have tangible benefits, prompting researchers to investigate whether such strategies might also improve outcomes for cancer patients. The Cleveland trial is one of several studies building on this foundation, following smaller experiments with kidney and lung cancers that showed promising results.
Van den Brink’s journey reflects the broader evolution of this field. In the 1990s, patients undergoing transplants were often confined to sterile environments, sometimes spending months in air-controlled suites to minimize infection risks. Nurses and families would interact with them through gloves that extended beyond the plastic barriers, a stark reminder of the fragility of the post-transplant period. Even with these precautions, many patients still faced life-threatening complications, which led to a reevaluation of treatment approaches.
The growing emphasis on the microbiome has transformed how cancer care is conceptualized. Researchers now understand that the gut’s microbial ecosystem can modulate immune responses, potentially influencing the success of therapies. For example, the gut microbiota may enhance the body’s ability to recognize and attack cancer cells, making it a critical factor in immunotherapy. This realization has driven initiatives like the Cleveland trial, which seeks to harness the power of probiotics to improve patient survival and recovery rates.
As the field advances, the microbiome is increasingly viewed as a therapeutic target rather than just a byproduct of digestion. The collaboration between institutions like the City of Hope Cancer Center and the National Cancer Institute exemplifies the cross-disciplinary efforts needed to unlock its potential. With nearly 700 participants in this new trial, the hope is that manipulating the gut microbiome could become a standard component of cancer treatment, offering a more personalized and effective approach to combating the disease.
The implications of this research extend beyond oncology, touching on broader health and wellness trends. From livestock to human patients, the role of gut bacteria in disease prevention and treatment is becoming undeniable. As studies continue to uncover its mechanisms, the microbiome may one day redefine how we understand and manage chronic illnesses, including cancer. For now, the focus remains on translating these insights into practical therapies, with the Cleveland trial representing a pivotal moment in that endeavor.
