Dr. Rick Jacobson, a surgical oncologist specializing in gastrointestinal and soft tissue tumors, has a gut feeling that postbiotics can support gastrointestinal cancer patients’ recovery.
There are as many bacterial cells in the gut as there are human cells in the body. Of the more than 5,000 different species of bacteria in that area, many are commensal organisms — the health-promoting bacteria that break down fiber into helpful substances. One such substance produced by commensal bacteria is short-chain fatty acids, which play an important role in the maintenance of health and the development of disease.
Bad bacteria compete with the good. Dr. Jacobson explains, “Bad bacteria are kind of the ‘bully of the gut playground,’ and the challenge, especially with people who are undergoing surgery for gastrointestinal cancers, is to keep those bullies at bay.”
Preparation for surgery can require many medications—including oral antibiotics, IV antibiotics, and bowel prep. While necessary, all of these can upset the gut’s good bacteria. In addition, surgery itself changes the amount of oxygen in the colon. Dr. Jacobson notes, “Most of these bacteria are anaerobes, so oxygen is toxic to them.”
Bacterial battles
He adds, “We inadvertently kill those good bacteria in order to minimize the risk of infections, but we have no control over what grows back.” The bad bacteria are often resistant to the antibiotics and can overgrow, creating an imbalance in the gut, as well as overgrowth of specific pathogens. Dr. Jacobson adds, “The one bacterium that I study the most is called Enterococcus, and it goes absolutely wild after surgery in a healthy individual.”
The bad bacteria can inflame the gut, creating an imbalance called dysbiosis, which after surgery can last for six months to a year. Dysbiosis can cause bloating and pain, and for some people, a lifetime of bowel-related issues. Another effect is that the gut can become “leakier.” Dr. Jacobson explains, “Usually, the lining of the colon is able to keep the bacteria on the inside. If they were able to escape or leak into the body, it could cause a bloodstream or belly infection or systemic inflammation.”
Gummies Helping Tummies
Taking postbiotics may be the key to encouraging good bacterial growth and discouraging the bad. In his clinical trial, Dr. Jacobson is focusing on how postbiotics improve the immune system, while reducing the pain and severity of gut dysbiosis caused by colon cancer surgery. He is the principal investigator for a clinical trial called “Postbiotics for Mitigation of Postoperative Dysbiosis in Colon Cancer Surgery” sponsored by the University of South Florida in Tampa.
As a part of the trial, patients receive one postbiotic gummy, called PoZibio® each day, seven days before surgery to promote the good bacteria and 90 days after surgery to help the good bacteria to grow back. The intent of the study is to prepare the colon for surgery by bolstering the good bacteria, so they have more opportunity to regrow quickly after surgery, hopefully outnumbering the bad bacteria.
Patients in the trial receive the postbiotics for free and also need to mail a stool sample five times over the pre-and-post surgery period in an easy-to-use, hands-free kit made by the University of South Florida Microbiome Center. Shipping is pre-labeled and pre-paid.
After surgery, the clinical trial team will track infection rates to determine if the immune system is functioning better to prevent postoperative infections. If the initial trial is successful, then the team hopes to open a large scale multi-institutional trial for other gastrointestinal cancers as well.
The trial is based on previous observations of postbiotics on mice. Dr. Jacobson says, “We’ve observed this to be safe and effective in our in our mouse models. And this is the next step for us.”
Improving long-term cancer outcomes
And it’s not just for symptomatic relief – Dr. Jacobson believes improved gut health can improve long-term cancer outcomes. “The immune system in our gut is constantly sampling the bacteria, and the presence of healthy bacteria in the colon helps our immune system function. If the bad bacteria are allowed to overgrow, the result can be immune dysfunction, and the immune system is one of the most important factors in in keeping cancer from returning.”
Several different types of “biotics” are used for gut health, and they act in different ways.
- Prebiotics are fermentable fibers, such as high fiber foods. As food for the bacteria, the good commensals digest them and use them to multiply and expand.
- Probiotics are a type of live bacteria contained in either yogurt or foods like kimchi or kombucha. These live bacteria engraft and grow in the gut, helping the body digest food.
- Postbiotics have all the benefits of live bacteria, but the bacteria are dead (killed with heat) and can’t multiply and grow in the gut. This is especially beneficial after surgery. Patients are so vulnerable that it may be too taxing to introduce a live strain into the gut when there is no control over what type of bacteria may grow back. Some reported findings suggest that postbiotics may play a role in maintaining the immune system, supporting digestion, lowering inflammation, and regulating blood sugar levels. The goal is to give all of these factors the boost they need to thrive.
“The postbiotic creates fertile ground for the good bacteria,” says Dr. Jacobson, “creating a mucus layer in the colon that promotes the growth of the bacteria that we want.” He adds, “After surgery is such a vulnerable time — 95% of the gut bacteria are dead, and the gut is delicate. We can’t flood the system with a live strain of bacteria like a probiotic. With a postbiotic, we can get the good effects without the potential bad.”
Boosting the gut microbiome is also important in improving response for those who are receiving immunotherapy.
Dr. Jacobson notes that taking a gummy once a day is easier than other ways of changing the gut microbiome. “In an ideal world, people would change their diets. Because it is thought that a plant-based diet helps people recover faster from surgery, it also prevents them from getting infections, and even some data suggests that it can keep your cancer from coming back. But, it’s so hard to change your diet on a long-term basis. From past experience, it has been very difficult to ask people to stick to a specific diet, even with upcoming surgery.”
“Patients have so many appointments for cancer care and are experiencing many side effects, but improving their gut health is an individual choice, and this gives them a little bit more control over what’s going on with their body.” Dr. Jacobson adds, “And besides, I’ve taken them myself, and those gummies are delicious.”
