title: Differentiation of human breast carcinoma cells by a novel vitamin D analog: 1alpha-hydroxyvitamin D5.
abstract: The active metabolite of vitamin D, 1alpha,25-dihydroxyvitamin D3, can induce differentiation in breast cancer cells; however, it is hypercalcemic in vivo. Therefore, development of non-calcemic analogs of vitamin D has received considerable attention. Recently, we synthesized an analog of vitamin D [1alpha(OH)D5] that exhibits much less calcemic activity than 1alpha,25-dihydroxyvitamin D3. In this study, we evaluated the cell-differentiating action of 1alpha(OH)D5 in breast cancer cells. Following 10 days treatment with 1alpha(OH)D5 [(10-7 M) in UISO-BCA-4], we observed induction of intracytoplasmic casein, intracytoplasmic lipid droplets, ICAM-1, nm23, and specific biomarkers associated with breast cell differentiation. 1alpha(OH)D5 treatment also showed induction of vitamin D receptor and TGFbeta1 proteins. UISO-BCA-4 cells pretreated for 10 days in vitro with 1 microM 1alpha(OH)D5 failed to form tumors when transplanted into athymic mice. Similarly, 4 and 8 ng 1alpha(OH)D5 treatment three times weekly inhibited the growth of UISO-BCA-4 cells injected into athymic mice. These results suggest that this new vitamin D analog may be of significant therapeutic value for breast cancer.
authors.affiliation: Department of Surgical Oncology, University of Illinois at Chicago, M/C 820, Chicago, IL 60612, USA.
authors.forename: R R
authors.initials: RR
authors.lastname: Mehta
authors.forename: L
authors.initials: L
authors.lastname: Bratescu
authors.forename: J M
authors.initials: JM
authors.lastname: Graves
authors.forename: A
authors.initials: A
authors.lastname: Green
authors.forename: R G
authors.initials: RG
authors.lastname: Mehta
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D015415:Biomarkers; D001943:Breast Neoplasms; D002454:Cell Differentiation / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D005260:Female; D006801:Humans; D006887:Hydroxycholecalciferols / Q000494:pharmacology* / Q000627:therapeutic use; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D014407:Tumor Cells, Cultured; D014807:Vitamin D / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: C103958:1-hydroxyvitamin D5; D000970:Antineoplastic Agents; D015415:Biomarkers; D006887:Hydroxycholecalciferols; D014807:Vitamin D