Okazaki T, Kato Y, Mochizuki T, Tashima M, Sawada H, Uchino H
Department of Internal Medicine, Faculty of Medicine, Kyoto University, Japan.
Exp Hematol. 1988 Jan;16(1):42-8.
The effect of staurosporine, a novel calcium/phospholipid-dependent protein kinase (protein kinase C) inhibitor, on differentiation of human promyelocytic leukemic HL-60 cells, was investigated. Staurosporine inhibited HL-60-cell proliferation in a concentration-dependent manner, but did not induce HL-60-cell differentiation by itself. When staurosporine was added to HL-60 cells treated with a suboptimal concentration (1 nM) of 1 alpha,25 dihydroxyvitamin D3 (1,25(OH)2D3), cell differentiation was enhanced in a concentration-dependent manner and the percentages of nitro blue tetrazolium reducing ability and nonspecific esterase activity-positive cells increased from 6% to 51% and from 8% to 54%, respectively, on day 4 at a concentration of 5 nM. Staurosporine (5 nM) achieved almost the same enhancement effect in cultures treated with suboptimal concentrations of 1 nM all-trans-beta-retinoic acid (RA), 3 ng/ml actinomycin D (Act D), 100 microM dibutyryl cyclic adenosine 3':5'-monophosphate (dbc AMP), and 50 microM prostaglandin E1 (PG E1). These results suggest that the inhibition of protein kinase C activity by staurosporine exerts an important role in HL-60-cell differentiation induced by various compounds. Moreover, staurosporine (5 nM) completely inhibited optimal concentrations (50 nM) of [12-o-tetradecanoyl phorbol-13-acetate (TPA)]-induced cell differentiation, but enhanced optimal concentrations of dbc AMP (1 mM)-induced cell differentiation. On the other hand, 1-(5-isoquinolinyl-sulfonyl)-2-methylpiperazine, which has been reported to inhibit cyclic adenosine 3':5'-monophosphate-dependent protein kinase (protein kinase A) as much as protein kinase C, completely inhibited both cell differentiations induced by optimal concentrations of TPA (50 nM) and induced by optimal concentrations of dbc AMP (1 mM), and did not significantly enhance HL-60-cell differentiation induced by suboptimal concentrations of 1,25(OH)2D3, RA, and dbc AMP. Therefore, these results suggest that the inhibition of protein kinase C, which is not accompanied by that of protein kinase A, is concerned with the induction of HL-60-cell differentiation.
研究了新型钙/磷脂依赖性蛋白激酶（蛋白激酶C）抑制剂星形孢菌素对人早幼粒细胞白血病HL-60细胞分化的影响。星形孢菌素以浓度依赖性方式抑制HL-60细胞增殖，但自身并不诱导HL-60细胞分化。当将星形孢菌素添加到用次优浓度（1 nM）的1α,25-二羟基维生素D3（1,25(OH)2D3）处理的HL-60细胞中时，细胞分化以浓度依赖性方式增强，在第4天，5 nM浓度下，硝基蓝四氮唑还原能力阳性细胞和非特异性酯酶活性阳性细胞的百分比分别从6%增加到51%和从8%增加到54%。在次优浓度的1 nM全反式维甲酸（RA）、3 ng/ml放线菌素D（Act D）、100 μM二丁酰环腺苷3':5'-单磷酸（dbc AMP）和50 μM前列腺素E1（PG E1）处理的培养物中，星形孢菌素（5 nM）产生了几乎相同的增强作用。这些结果表明，星形孢菌素对蛋白激酶C活性的抑制在各种化合物诱导的HL-60细胞分化中发挥重要作用。此外，星形孢菌素（5 nM）完全抑制了最佳浓度（50 nM）的[12-O-十四烷酰佛波醇-13-乙酸酯（TPA）]诱导的细胞分化，但增强了最佳浓度的dbc AMP（1 mM）诱导的细胞分化。另一方面，据报道可同等程度抑制环腺苷3':5'-单磷酸依赖性蛋白激酶（蛋白激酶A）和蛋白激酶C的1-(5-异喹啉基磺酰基)-2-甲基哌嗪，完全抑制了最佳浓度的TPA（50 nM）诱导的细胞分化和最佳浓度的dbc AMP（1 mM）诱导的细胞分化，并且并未显著增强次优浓度的1,25(OH)2D3、RA和dbc AMP诱导的HL-60细胞分化。因此，这些结果表明，不伴随蛋白激酶A抑制的蛋白激酶C抑制与HL-60细胞分化的诱导有关。
