Combination of diet, bacteria, limits cancer progression

A combination of prebiotics, such as dietary fiber, and probiotics reduces the expression of pro-carcinogenic and drug resistance genes, according to a new study published in the journal Cell Reports.

The combination leads to metabolic changes that affect the growth of cancer cells and may help treat diseases such as colorectal cancer, said researchers from the University of Luxembourg.

To study the diet-microbiome-host interactions, researchers worked with Human-Microbial X(cross)-talk (HuMiX), an in vitro model of the gut that allows he cultivation of human intestinal cells together with bacteria under representative conditions. Researchers investigated the effects of dietary regimens and a specific probiotic on colorectal cancer cells.

The diet of a person can have significant effects on the gut microbiome, the populations of microorganisms such as bacteria that live in the human gut. It is well recognized that dietary habits through complex metabolic interactions contribute to cancer prevention. More specifically, diets rich in fiber reduce the risk of developing specific cancers such as colorectal cancer. Although such diets are an effective means of cancer prevention, their possible roles in cancer progression and treatment remains poorly understood.

In contrast to individual fiber-rich or probiotic treatments, researchers found only the combination of fiber and probiotics led to the observed beneficial effects. The researchers integrated a computer-based metabolic model of the interactions between diet, host, and microbiome. They identified the effects of the combined treatment, the downregulation of genes associated with colorectal cancer and drug-resistance, as well as the attenuation of self-renewal capacity of the cancer cells.

Through careful molecular analyses, the researchers also identified the cocktail of molecules produced by the combination, thereby providing a mechanistic basis for the observed beneficial effects.