Silica induce cell cycle changes by mitogen-activated protein kinases pathway / 中华劳动卫生职业病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the roles of mitogen-activated protein kinases (MAPK) on silica-induced cell cycle changes.</p><p><b>METHODS</b>After cells were treated with 200 microg/ml silica, Western blot and Immunofluorescence assays were utilized to detect the expression of cyclin D1, CDK4 and E2F-4, Flow cytometry was used to detect cell cycle progression, the dominant negative mutants techniques were used to investigate silica-induced signal pathway and the effects of which in silica-induced cell cycle changes.</p><p><b>RESULTS</b>After cells were exposed to 200 microg/ml silica 24 h, the results of present study showed the proportion of cells in G1 phases was decreased. Silica-induced cell cycle alternation was markedly impaired by stable expression of a dominant negative mutants of ERK or JNK, but not p38. It was found that ERK and JNK were involved in silica-induced cyclin D1 and CDK4 overexpression and the decreased expression of E2F-4.</p><p><b>CONCLUSION</b>ERK and JNK, but not p38, mediated silica-induced cell cycle changes in human embryo lung fibroblasts.</p>