1 alpha,25-Dihydroxyvitamin D3 and 1 alpha-hydroxyvitamin D3 prolong survival time of mice inoculated with myeloid leukemia cells.
Syngeneic SL mice inoculated with murine myeloid leukemia cells (M1) all died of leukemia within 30 days. Treatment three times a week with 12.5-50 pmol per mouse of either 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3], the active form of vitamin D3, or its synthetic analog, 1 alpha-hydroxyvitamin D3 [1 alpha(OH)D3], considerably prolonged the survival time of mice inoculated with M1 cells. 1 alpha(OH)D3 was more effective than 1 alpha,25(OH)2D3 in increasing the survival time of the mice. 1 alpha(OH)D3 also increased the survival time of nude mice inoculated with M1 cells. The 1 alpha(OH)[3H]D3 administered intraperitoneally to tumor-bearing mice was converted very rapidly to 1 alpha,25(OH)2-[3H]D3. The chronic administration of 25 pmol of 1 alpha(OH)D3 to tumor-bearing mice for 30 days caused no appreciable hypercalcemia. These results indicate clearly that 1 alpha,25(OH)2D3 is effective not only in inducing differentiation of M1 cells in vitro, as previously reported [Abe, E., Miyaura, C., Sakagami, H., Takeda, M., Konno, K., Yamazaki, T., Yoshiki, S. & Suda, T. (1981) Proc. Natl. Acad. Sci. USA 78, 4990-4994], but also in prolonging the survival time of mice inoculated with M1 cells.
D000818:Animals; D002117:Calcitriol / Q000627:therapeutic use; D002118:Calcium / Q000097:blood; D002762:Cholecalciferol / Q000627:therapeutic use*; D006887:Hydroxycholecalciferols / Q000378:metabolism / Q000627:therapeutic use; D007942:Leukemia, Experimental / Q000188:drug therapy*; D051379:Mice; D009368:Neoplasm Transplantation; D010758:Phosphorus / Q000097:blood
D006887:Hydroxycholecalciferols; D002762:Cholecalciferol; D010758:Phosphorus; D002117:Calcitriol; D002118:Calcium