title: Identification and expansion of human colon-cancer-initiating cells.
abstract: Colon carcinoma is the second most common cause of death from cancer. The isolation and characterization of tumorigenic colon cancer cells may help to devise novel diagnostic and therapeutic procedures. Although there is increasing evidence that a rare population of undifferentiated cells is responsible for tumour formation and maintenance, this has not been explored for colorectal cancer. Here, we show that tumorigenic cells in colon cancer are included in the high-density CD133+ population, which accounts for about 2.5% of the tumour cells. Subcutaneous injection of colon cancer CD133+ cells readily reproduced the original tumour in immunodeficient mice, whereas CD133- cells did not form tumours. Such tumours were serially transplanted for several generations, in each of which we observed progressively faster tumour growth without significant phenotypic alterations. Unlike CD133- cells, CD133+ colon cancer cells grew exponentially for more than one year in vitro as undifferentiated tumour spheres in serum-free medium, maintaining the ability to engraft and reproduce the same morphological and antigenic pattern of the original tumour. We conclude that colorectal cancer is created and propagated by a small number of undifferentiated tumorigenic CD133+ cells, which should therefore be the target of future therapies.
authors.affiliation: Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome 00161, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Ricci-Vitiani
authors.forename: Dario G
authors.initials: DG
authors.lastname: Lombardi
authors.forename: Emanuela
authors.initials: E
authors.lastname: Pilozzi
authors.forename: Mauro
authors.initials: M
authors.lastname: Biffoni
authors.forename: Matilde
authors.initials: M
authors.lastname: Todaro
authors.forename: Cesare
authors.initials: C
authors.lastname: Peschle
authors.forename: Ruggero
authors.initials: R
authors.lastname: De Maria
mesh_terms: D000071916:AC133 Antigen; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D009368:Neoplasm Transplantation; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology*; D010455:Peptides / Q000378:metabolism*; D010641:Phenotype; D014183:Transplantation, Heterologous
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; C000606024:Prom1 protein, mouse