Inhibition by 1 alpha,25-dihydroxyvitamin D3 of dimethyl sulfoxide-induced differentiation of Friend erythroleukemia cells.

Regulation of erythroid differentiation by vitamin D3 derivatives was examined in Friend erythroleukemia cells. After Friend cells were cultured for 5 days with 1.5% dimethyl sulfoxide (DMSO), as much as 70% of the cells became benzidine-positive and the hemoglobin content increased in parallel with the increase of benzidine-positive cells. The DMSO-induced erythroid differentiation was markedly inhibited by concurrent addition of the active form of vitamin D3, 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3]. Of the vitamin D3 derivatives tested, 1 alpha,25(OH)2D3 was the most potent in inhibiting DMSO-induced erythroid differentiation. 1 alpha,25(OH)2D3 alone was totally ineffective in both cell growth and erythroid differentiation. These results together with our previous reports indicate that 1 alpha,25(OH)2D3 is somehow involved not only in myeloid differentiation, but also in erythroid differentiation.