Effects of pectins on colorectal cancer: targeting hallmarks as a support for future clinical trials

The intake of dietary fibers has been associated with a reduction in the risk of colorectal cancer. Pectins - a class of dietary fibers - are polysaccharides that have a complex structure with a wide range of direct and indirect biological beneficial effects on humans. Direct effects include dilution of carcinogens, reduction in cholesterol levels, and interaction with immune cells. Indirect effects include the fermentation and production of short-chain fatty acids. All these biological effects have implications for colon cancer development; however, the exact mechanisms are not fully understood. In this review, we explore the clinical trials regarding dietary fibers and colorectal cancer, thus indicating the potential anti-cancer effects of pectins and modified pectins. We focused on the emerging biological effects of pectins through targeting colorectal cancer hallmark effects and the enabling characteristics. We provide an overview of the mechanisms for each hallmark capability and how the different pectins might exert that anti-cancer effect, such as induction of apoptosis, reduction in cancer cell proliferation and metastasis. The data compilation described herein can guide future clinical trials to investigate how to target specific pectin structures to act as an adjuvant in colon cancer treatment.