Hegemann L, Wevers A, Bonnekoh B, Mahrle G
Department of Dermatology, University of Köln, Germany.
J Dermatol Sci. 1992 Mar;3(2):103-10. doi: 10.1016/0923-1811(92)90043-b.
Several lines of evidence show protein kinase C as being involved in various regulatory processes in keratinocyte biology, e.g. proliferation and differentiation. In the present study, we investigated the effects of three different inhibitors of protein kinase C, staurosporine, CP 46'665-1, and tiflucarbine, on cell morphology and keratin expression in a non-tumorigenic human keratinocyte cell line (HaCaT cells). Staurosporine, being the most potent inhibitor of protein kinase C activity in vitro, and CP 46'665-1 induced morphological transformation to a fibroblast-like cell shape. In contrast, no changes in cell morphology were observed after exposure to tiflucarbine. The investigation of keratin expression in HaCaT cells grown in the presence of the different compounds revealed the following changes: After 72 h of cultivation, keratins 8 and 18 were still expressed in treated cells, whereas expression of keratin 13 was decreased as compared to control cells. Immunoblotting to detect vimentin demonstrated its absence in treated and control cells. Since tiflucarbine is known as a dual protein kinase C/calmodulin inhibitor whereas staurosporine and CP 46'665-1 do not antagonize calmodulin function, it might be possible that not only protein kinase C but also calmodulin is involved in the process leading to the morphological changes.
多项证据表明蛋白激酶C参与角质形成细胞生物学中的各种调节过程，例如增殖和分化。在本研究中，我们研究了三种不同的蛋白激酶C抑制剂，即星形孢菌素、CP 46'665-1和替氟卡宾，对非致瘤性人角质形成细胞系（HaCaT细胞）的细胞形态和角蛋白表达的影响。星形孢菌素是体外蛋白激酶C活性最有效的抑制剂，CP 46'665-1诱导细胞形态转变为成纤维细胞样形状。相比之下，暴露于替氟卡宾后未观察到细胞形态变化。对在不同化合物存在下生长的HaCaT细胞中的角蛋白表达进行的研究揭示了以下变化：培养72小时后，处理过的细胞中仍表达角蛋白8和18，而与对照细胞相比，角蛋白13的表达降低。检测波形蛋白的免疫印迹显示其在处理过的细胞和对照细胞中均不存在。由于替氟卡宾是一种双重蛋白激酶C/钙调蛋白抑制剂，而星形孢菌素和CP 46'665-1不拮抗钙调蛋白功能，不仅蛋白激酶C而且钙调蛋白可能参与导致形态变化的过程。
