LGR5 and intestinal neoplasm: Several signaling pathways are involved in ISCs homeostasis, including the Wnt and Notch signaling pathways.[4] The leucine-rich repeat containing the G-protein-coupled receptor 5 (LGR5) gene has been identified as a specific intestinal stem cell marker and plays a crucial role in Wnt/β-catenin signaling, which eventually catalyzes the self-renewal of ISCs.[4,5] Thus, disruption of Wnt signaling might result in abnormal proliferation of the intestinal epithelium and development of intestinal tumors.[6]