1,25-Dihydroxyvitamin D3-induced growth restriction of cultured epithelial cells derived from a murine hepatic tumor.
Recent evidence suggests that 1,25-dihydroxyvitamin D3 can accumulate in certain presumed non-target tissues, although the mechanism of action of the vitamin in such cells is not understood. Exposure of 77-1/3a mouse hepatic tumor cells, which derived from a non-target tissue of vitamin D action, to 1,25-dihydroxyvitamin D3 in chemically-defined serum-free medium resulted in a dose-dependent decline in cellular growth rate and maximal culture population density but did not adversely affect cell viability. Culture of 77-1/3a cells in defined medium containing 10(-7) or 10(-6) M 1,25-dihydroxyvitamin D3 for 150 hr reduced the growth rate to 64 and 50% of control values respectively. Albumin secretion was unaffected by 1,25-dihydroxyvitamin D3 exposure; in contrast, the cellular content of the proliferation-associated protein p35 was reduced by 39%, a decline similar in trend and degree to that observed in other tumor cells exposed to differentiation-inducing agents. It appears that 1,25-dihydroxyvitamin D3 regulates cellular p35 content (within a specific restricted range) as a consequence of proliferative perturbation, rather than differentiated status, of cultured hepatic tumor cells.
Tanaka
Y
Y
Veterans Administration Medical Center, Albany, NY 12208.
Higgins
P J
PJ
Jubiz
W
W
D000818:Animals; D002117:Calcitriol / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D003470:Culture Media; D004848:Epithelium / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000473:pathology*; D051379:Mice; D014407:Tumor Cells, Cultured
D003470:Culture Media; D002117:Calcitriol