title: Intestinal stem cells - types and markers.
abstract: Intestinal epithelium is a rapidly cycling tissue, always renewing every 4-5 days under normal conditions, which is maintained by intestinal stem cells (ISCs). Using the fluorescence labelling trace, ISCs can be divided into two different types: active intestinal stem cells (A-ISCs) located in bottom of the intestinal crypt and the quiescent intestinal stem cells (Q-ISCs) in the +4 position of the crypt. There is a complex signal regulation net between the ISCs and other intestinal cells, such as Wnt and Notch pathways. ISCs have an intimate relationship with the colorectal cancer (CRC). However, a deficiency of stem cells markers severely limits research on the biological characteristics of ISCs. We have reviewed several ISCs markers, including Lgr5, PHLDA1, Bmi1 and Lrig1. These markers have widely different biological functions, but also have a close relationship with cancers, especially CRC. Our hypothesis concerns the reasons for ISCs having two distinct types and why endless ISCs markers have emerged.
authors.affiliation: Cancer Institute, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China. zhigangzhang87@yahoo.cn
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology*; D008562:Membrane Glycoproteins / Q000378:metabolism; D063150:Polycomb Repressive Complex 1 / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C069077:BMI1 protein, human; D015415:Biomarkers; C116884:LGR5 protein, human; C484445:LRIG1 protein, human; D008562:Membrane Glycoproteins; C491923:PHLDA1 protein, human; D043562:Receptors, G-Protein-Coupled; D014157:Transcription Factors; D063150:Polycomb Repressive Complex 1