What gut bacteria can teach us about cancer treatment

At one time, the role of gut bacteria in human health was marginalized as a side note that health experts found interesting but not integral. But as more and more research has made clear, the number and diversity of bacteria in the gut can often make the difference between health and disease. Two new studies have found that gut bacteria can also determine the effectiveness of the treatments that are used to fight cancer, forcing doctors to take a closer look at the lessons they can learn from this once overlooked aspect of human health.

In one experiment, researchers at the University of Lille in France looked at ipilimumab — a cancer drug used to treat advanced melanoma — and found that not only did the medication affect the amount of bacteria that was in the gut, but its own effectiveness went hand-in-hand with the level of bacteria trial participants had in their intestines. So the very drug that needed gut bacteria in order to work was the thing that was destroying participants’ gut bacteria levels. Researchers found that when they gave participants supplemental levels of bacteria along with ipilimumab, they responded better to treatment.

A second study — conducted by researchers at the University of Chicago — confirmed the importance of gut bacteria in cancer treatment. For this study, researchers looked at the growth of tumors in two sets of animal subjects and compared that to the profile of bacteria in their intestines. Researchers found that mice who had the bacteria Bifidobacteria in their guts had slower tumor growth than those who did not. When the team transplanted this bacteria into the intestines of the mice that did not have it, they too experienced slowed tumor growth. And this was without any additional drug or treatment.

The takeaway from these two studies is that gut bacteria is very important in the treatment of disease. Of course, both of these studies were conducted on mice, so more work needs to be done to further define the role of gut bacteria in human health. But even at this stage of the game, many health experts are recommending that health care providers evaluate gut bacteria for their patients before beginning any type of treatment and replenish bacteria as necessary to improve the effectiveness of treatment.

credit: jenn Savegde

Manipulating gut bacteria may cure disease, study shows

Researchers fed volunteers extreme diets of meat and cheese followed by extreme diets of grains and vegetables and found gut bacteria changed greatly according to diet.
I started paying attention to information about gut bacteria after my friend Amanda started educating me about fermenting food. She introduced me to the fact that science is increasingly linking many food-related ailments to our gut bacteria. I’m still learning about it, and I found the results of a recent study interesting.

The scientific study by Harvard University scientists put volunteers on extreme diets to see if consumption of certain foods can significantly alter gut bacteria in a short period of time.

A group of nine volunteers were first put on an extreme diet of meat, eggs and cheese for five days. After a break, the same volunteers were then put on an all plant-based diet of legumes, grains, fruits and vegetables.

During both time periods, the change in gut bacteria was evident after three days. When the gut bacteria of the volunteers during the animal-product only diet was tested, their guts began to make “microbes that ‘love bile’ — the Bilophila.” It’s believed that Bilophila promotes inflammation in the stomach. When the volunteers ate the plant-only diet, there was not an increase in Bilophila.

Of course, the meat diet was extreme, and for many people, the plant-based only diet was extreme also. Most of us, except for vegans, eat a combination of plant and animal products. If so, why should we be interested in the results of this study?

The results are interesting, and I’d also say they’re important, because as study contributor Dr. Lawrence David noted, “Our study is a proof of concept that you can modify the microbiome through diet.” It’s an initial step in figuring out how to treat intestinal diseases with diet.

The researchers admit they are a long way off from being able to “manipulate the community” of bacteria in a person’s stomach to actually treat disease, but it’s a step in the right direction. That’s why the study is important. When the scientific community is working to discover how changing what we eat can treat diseases, instead of just creating drugs that will manage the diseases that our diets may create, it’s important.

Source: Robin Shreeves