title: Expression of HOX homeobox genes in the adult human colonic mucosa (and colorectal cancer?).
abstract: We studied the expression of several homeobox genes of the HOX family in the adult human intestinal mucosa. HOX genes are regulatory genes homologous to the homeotic genes controlling the body plan of the fruit fly Drosophila melanogaster. The HOX genes are distributed in four homologous HOX loci termed HOX-A, B, C and D, located on four different chromosomes. They have been found to be expressed in many embryonic tissues and axial structures like the central nervous system, the spine and in selected adult cells. The expression of 39 HOX genes belonging to HOX-A, B, C and D was studied by in situ hybridization on specimens of mucosa from normal adult colon. All the genes studied were shown to be expressed in these tissues, but the genes belonging to the four loci showed different localization within the colonic mucosa: HOX-A genes are expressed in undifferentiated proliferating cells at the base of the crypts, HOX-C genes in differentiated cells at the apex of the crypts and HOX-B and HOX-D genes are weakly expressed along the entire crypt length. Expression of some of these genes was also studied in differentiating CaCo-2 cells and tumoral tissues. In particular, in colonic adenocarcinomatous cells, some HOX-A genes appear to be abundantly expressed confirming the presence of these gene products in normal.
authors.affiliation: Department of Surgical Pathology, University of Florence, Italy. giancarlo.freschi@unifi.it
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Freschi
authors.forename: Antonio
authors.initials: A
authors.lastname: Taddei
authors.forename: Paolo
authors.initials: P
authors.lastname: Bechi
authors.forename: Antonio
authors.initials: A
authors.lastname: Faiella
authors.forename: Massimo
authors.initials: M
authors.lastname: Gulisano
authors.forename: Clemente
authors.initials: C
authors.lastname: Cillo
authors.forename: Giorgio
authors.initials: G
authors.lastname: Bucciarelli
authors.forename: Edoardo
authors.initials: E
authors.lastname: Boncinelli
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000473:pathology; D000328:Adult; D018938:Caco-2 Cells; D003106:Colon / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology; D015870:Gene Expression; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D017403:In Situ Hybridization; D007413:Intestinal Mucosa / Q000378:metabolism*; D005810:Multigene Family / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D018398:Homeodomain Proteins; D012333:RNA, Messenger