[Silica induce cell cycle changes by mitogen-activated protein kinases pathway].
OBJECTIVE
To investigate the roles of mitogen-activated protein kinases (MAPK) on silica-induced cell cycle changes.


METHODS
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.


RESULTS
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.


CONCLUSIONS
ERK and JNK, but not p38, mediated silica-induced cell cycle changes in human embryo lung fibroblasts.
National Institute of Occupation Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Xiao-Wei
XW
Jia
Bing-Ci
BC
Liu
Meng
M
Ye
Hai-Feng
HF
Liu
Feng-Mei
FM
Zhang
D002453:Cell Cycle / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000473:pathology*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D011791:Quartz / Q000633:toxicity*
D011791:Quartz; D020928:Mitogen-Activated Protein Kinases