LGR5 and obesity due to melanocortin 4 receptor deficiency: Numerous epidemiological studies have established strong evidence that many cancers including colon cancer have substantial risk proportions attributed to extrinsic factors such as diet, smoking and obesity.1 High fat diet (HFD)-induced obesity augments stemness and tumorigenicity of intestinal progenitors.2 In addition, epithelial colonic leucine-rich repeat-containing G-protein-coupled receptor 5-positive (Lgr5)+ stem cells respond to HFD3 and genotoxic carcinogen, for example, AOM,4 during the cancer initiation stage.