c-Src regulates cell cycle proteins expression through protein kinase B/glycogen synthase kinase 3 beta and extracellular signal-regulated kinases 1/2 pathways in MCF-7 cells  

作　　者：Xiang Liu Liying Du Renqing Feng 

机构地区：[1]Department of Biochemistry and Molecular Biology, College of Life Sciences, Peking University, Beijing 100871, China [2]present address: Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institute of Health,Bethesda, MD 20892, USA

出　　处：《Acta Biochimica et Biophysica Sinica》2013年第7期586-592,共7页生物化学与生物物理学报（英文版）

基　　金：We thank Professor Yuxian Zhu and Zhenquan Guo （College of Life Sciences, Peking University, Peking, China） for guidance in accomplishing this work and Dr Zachary Klase （National Institutes of Health, Bethesda, USA） for critical reading of the manuscript.This work was supported by the grants from the National Natural Science Foundation of China （81272379） and Beijing Natural Science Foundation （5092012）.

摘　　要：We have demonstrated that c-Src suppression inhibited the epithelial to mesenchymal transition in human breast cancer cells. Here, we investigated the role of c-Src on the cell cycle progression using siRNAs and small molecule inhibitor 4-amino-5-（4-chlorophenyl）-7-（t-butyl）pyrazolo [3,4-d]pyrimi-dine （PP2）. Western blot analysis demonstrated the down- regulation of cyclin D1 and cyclin E and up-regulation of p27 Kipl after c-Src suppression by PP2. Incubation of cells in the presence of PP2 significantly blocked the phosphoryl- ation of extracellular signal-regulated kinases 1/2 （ERK1/2）, protein kinase B （AKT）, and glycogen synthase kinase 3 beta （GSK3β）. Specific pharmacological inhibitors of MEK1/2/ERK1/2 and phosphatidylinositide 3-kinase/AKT pathways were used to demonstrate the relationship between the signal cascade and cell cycle proteins expression. The ex-pression of cyclin D1 and cyclin E were decreased after in-hibition of ERK1/2 or AKT activity, whereas the p27 Kipl expression was increased. In addition, knockdown of c-Src by siRNAs reduced cell proliferation and phosphorylation of ERK1/2, AKT, and GSKβ After c-Src depletion by siRNAs, we observed significant down-regulation of cyclin D1 and cyclin E, and up-regulation of p27 Kipl. These results suggest that c-Src suppression by PP2 or siRNAs may regulate the progression of cell cycle through AKT/ GSK3β and ERK1/2 pathways.We have demonstrated that c-Src suppression inhibited the epithelial to mesenchymal transition in human breast cancer cells. Here, we investigated the role of c-Src on the cell cycle progression using siRNAs and small molecule inhibitor 4-amino-5-（4-chlorophenyl）-7-（t-butyl）pyrazolo [3,4-d]pyrimi-dine （PP2）. Western blot analysis demonstrated the down- regulation of cyclin D1 and cyclin E and up-regulation of p27 Kipl after c-Src suppression by PP2. Incubation of cells in the presence of PP2 significantly blocked the phosphoryl- ation of extracellular signal-regulated kinases 1/2 （ERK1/2）, protein kinase B （AKT）, and glycogen synthase kinase 3 beta （GSK3β）. Specific pharmacological inhibitors of MEK1/2/ERK1/2 and phosphatidylinositide 3-kinase/AKT pathways were used to demonstrate the relationship between the signal cascade and cell cycle proteins expression. The ex-pression of cyclin D1 and cyclin E were decreased after in-hibition of ERK1/2 or AKT activity, whereas the p27 Kipl expression was increased. In addition, knockdown of c-Src by siRNAs reduced cell proliferation and phosphorylation of ERK1/2, AKT, and GSKβ After c-Src depletion by siRNAs, we observed significant down-regulation of cyclin D1 and cyclin E, and up-regulation of p27 Kipl. These results suggest that c-Src suppression by PP2 or siRNAs may regulate the progression of cell cycle through AKT/ GSK3β and ERK1/2 pathways.

关 键 词：breast cancer cell cycle proteins c-Srcsuppression PP2 SIRNAS 

分 类 号：Q463[生物学—生理学] Q253