Remodeling of the Gut Microbiota in Colorectal Cancer and its Association with Obesity

The considerable burden of colorectal cancer and the increasing prevalence in young adults emphasizes the necessity of understanding its underlying mechanisms and risk factors as well as providing more effective treatments. There is growing evidence of a positive relationship between obesity and colorectal cancer. Furthermore, the prominent role of gut microbiota dysbiosis in colorectal carcinogenesis is becoming more evident. Sequencing studies demonstrate an altered composition and ecology of intestinal microorganisms in both colorectal cancer and obese patients and have pinpointed some specific bacteria as the key role players. The purpose of this review is to provide a general outlook of how gut microbiota may impact the initiation and promotion of colorectal cancer and describes probable links between gut microbiota and obesity. We also provide evidence about targeting the microbiota as an intervention strategy for both ameliorating the risk of cancer and augmenting the therapy efficacy.