title: 25-hydroxyvitamin D-1alpha-hydroxylase in normal and malignant colon tissue.
abstract: Vitamin D affects calcium metabolism and prevents proliferation of colon cells in vitro. In human beings the main circulating form of vitamin D is 25-hydroxyvitamin D; to regulate calcium homoeostasis, this form must be converted to 1alpha, 25-dihydroxyvitamin D by 1alpha-hydroxylation in the kidney with 25-hydroxyvitamin D-1alpha-hydroxylase. Cultured transformed colon cancer cells can convert 25-hydroxyvitamin D(3) to 1alpha,25-dihydroxyvitamin D(3). We identified messenger RNA (mRNA) for 25-hydroxyvitamin D-1alpha-hydroxylase in normal colon tissue and in malignant and adjacent normal colon tissue. These findings support the notion that vitamin D might have a role in cell growth regulation and cancer protection, and might be the explanation for why the risk of dying from colorectal cancer is highest in areas with the least amount of sunlight.
authors: V
authors: V
authors: Tangpricha
authors: J N
authors: JN
authors: Flanagan
authors: L W
authors: LW
authors: Whitlatch
authors: C C
authors: CC
authors: Tseng
authors: T C
authors: TC
authors: Chen
authors: P R
authors: PR
authors: Holt
authors: M S
authors: MS
authors: Lipkin
authors: M F
authors: MF
authors: Holick
mesh_terms: D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000235:genetics*; D002118:Calcium / Q000378:metabolism; D002423:Cause of Death; D002455:Cell Division / Q000235:genetics; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000401:mortality / Q000473:pathology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics*; D012016:Reference Values; D013472:Sunlight; D016019:Survival Analysis; D014807:Vitamin D / Q000502:physiology
chemical_list: D012333:RNA, Messenger; D014807:Vitamin D; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase; D002118:Calcium