title: Cancer stem cell subsets and their relationships.
abstract: Emerging evidence suggests that cancer stem cells account for the initiation and progression of cancer. While many types of cancer stem cells with specific markers have been isolated and identified, a variety of differences among them began to be appreciated. Cancer stem cells are hierarchical populations that consist of precancerous stem cells, primary cancer stem cells, migrating cancer stem cells and chemoradioresistant cancer stem cells, playing different roles in cancer initiation and progression. Here we propose a new concept "horizontal hierarchy of cancer stem cells" to distinguish them from vertical hierarchy cancer stem cells, cancer transient-amplifying cells and cancer differentiated cells, and summarize our current understanding of these subsets of cancer stem cells with the aim to open up novel therapeutic strategies for cancer based on this understanding.
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Hai-Guang
authors.initials: HG
authors.lastname: Liu
authors.forename: Chong
authors.initials: C
authors.lastname: Chen
authors.forename: Han
authors.initials: H
authors.lastname: Yang
authors.forename: Yi-Fei
authors.initials: YF
authors.lastname: Pan
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002465:Cell Movement; D019008:Drug Resistance, Neoplasm; D006801:Humans; D014411:Neoplastic Stem Cells / Q000473:pathology*; D011230:Precancerous Conditions / Q000473:pathology*; D011836:Radiation Tolerance