Somatic stem cells maintain tissue homeostasis by organizing themselves in such a way that they can maintain proliferative output while simultaneously protecting themselves from DNA damage that may lead to oncogenic transformation. There is considerable debate about how such stem cell compartments are organized. Burgeoning evidence from the small intestine and colon provides support for a two-stem cell model involving an actively proliferating but injury-sensitive stem cell and a rare, injury-resistant pool of quiescent stem cells. Parallel with this evidence, recent studies have revealed considerable plasticity within the intestinal stem cell (ISC) compartment. We discuss the evidence for plasticity and hierarchy within the ISC compartment and how these properties govern tissue regeneration and contribute to oncogenic transformation leading to colorectal cancers.

成体干细胞通过组织自身来维持组织稳态，使它们能够维持增殖输出，同时保护自身免受可能导致致癌转化的 DNA 损伤。关于这些干细胞区室是如何组织的存在相当大的争论。来自小肠和结肠的新兴证据支持两种干细胞模型，包括活跃增殖但对损伤敏感的干细胞和罕见的抗损伤静止干细胞库。与此证据平行的是，最近的研究表明肠道干细胞 (ISC) 隔室内具有相当大的可塑性。