title: 25-hydroxyvitamin D3-1alpha-hydroxylase expression in normal and malignant human colon.
abstract: 1,25-dihydroxyvitamin D(3) has anti-mitotic, pro-differentiating, and pro-apoptotic activity in tumor cells. We demonstrated that the secosteroid can be synthesized and degraded not only in the kidney but also extrarenally in intestinal cells. Evaluation of 1,25-dihydroxyvitamin D(3)-synthesizing CYP27B1 hydroxylase mRNA (real-time PCR) and protein (immunoblotting, immunofluorescence) showed enhanced expression in high- to medium-differentiated human colon tumors compared with tumor-adjacent normal mucosa or with colon mucosa from non-cancer patients. In high-grade undifferentiated tumor areas expression was lost. Many cells co-expressed CYP27B1 and the vitamin D receptor. We suggest that autocrine/paracrine antimitotic activity of 1,25-dihydroxyvitamin D(3) could prevent intestinal tumor formation and progression.
authors.affiliation: Department of Pathophysiology, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna, Austria.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Bises
authors.forename: Enikö
authors.initials: E
authors.lastname: Kállay
authors.forename: Tina
authors.initials: T
authors.lastname: Weiland
authors.forename: Friedrich
authors.initials: F
authors.lastname: Wrba
authors.forename: Etienne
authors.initials: E
authors.lastname: Wenzl
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Bonner
authors.forename: Stefan
authors.initials: S
authors.lastname: Kriwanek
authors.forename: Peter
authors.initials: P
authors.lastname: Obrist
authors.forename: Heide S
authors.initials: HS
authors.lastname: Cross
mesh_terms: D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000096:biosynthesis* / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis
chemical_list: D012333:RNA, Messenger; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase