Cross-regulation between protein L-isoaspartyl O-methyltransferase and ERK in epithelial mesenchymal transition of MDA-MB-231 cells  

作　　者：Jiyeon RYU Jihyeok SONG Jieun HEO Yongwoo JUNG Sang-Jin LEE Sungyoul HONG Jae Youl CHO 

机构地区：[1]Department of Genetic Engineering, Sungkyunkwan University, Suwon 440-746, Korea

出　　处：《Acta Pharmacologica Sinica》2011年第9期1165-1172,共8页中国药理学报（英文版）

摘　　要：Aim： Protein L-isoaspartyl O-methyltransferase （PIMT） regulates cell adhesion in various cancer cell lines through activation of integrin av and the PI3K pathway. The epithelial mesenchymal transition （EMT） enables epithelial cells to acquire the characteristics of mesenchymal cells, and to allow them to migrate for metastasis. Here, we examined the relationship between PIMT and EMT with attached or detached MDA-MB 231 cells. Methods： Human breast cancer cell line MDA-MB-231 cells were maintained in a suspension on poly-HEMA in the presence or absence of PIMT siRNA or ERK inhibitor PD98059. The mRNAs and proteins were analyzed using RT-PCR and immunoblotting, respectively. Results： During cellular incubation under detached conditions, PIMT, integrin av and EMT proteins, such as Snail, Slug and matrix met- alloproteinase 2 （MMP-2）, were significantly increased in correlation with the phosphorylation of ERK1/2. The ERK inhibitor PD98059 （25 pmol/L） strongly suppressed the expression of the proteins and PIMT. Interestingly, PIMT siRNA blocked the phosphorylation of ERK and the expression of the EMT proteins. Additionally, PIMT and ERK phosphorylation were both co-activated by treatment with TGF-β （10 ng/mL） and TNF-α （10 ng/mL）. Conclusion： A tight cross-regulation exists between ERK and PIMT in regards to their activation and expression during the EMT.Aim： Protein L-isoaspartyl O-methyltransferase （PIMT） regulates cell adhesion in various cancer cell lines through activation of integrin av and the PI3K pathway. The epithelial mesenchymal transition （EMT） enables epithelial cells to acquire the characteristics of mesenchymal cells, and to allow them to migrate for metastasis. Here, we examined the relationship between PIMT and EMT with attached or detached MDA-MB 231 cells. Methods： Human breast cancer cell line MDA-MB-231 cells were maintained in a suspension on poly-HEMA in the presence or absence of PIMT siRNA or ERK inhibitor PD98059. The mRNAs and proteins were analyzed using RT-PCR and immunoblotting, respectively. Results： During cellular incubation under detached conditions, PIMT, integrin av and EMT proteins, such as Snail, Slug and matrix met- alloproteinase 2 （MMP-2）, were significantly increased in correlation with the phosphorylation of ERK1/2. The ERK inhibitor PD98059 （25 pmol/L） strongly suppressed the expression of the proteins and PIMT. Interestingly, PIMT siRNA blocked the phosphorylation of ERK and the expression of the EMT proteins. Additionally, PIMT and ERK phosphorylation were both co-activated by treatment with TGF-β （10 ng/mL） and TNF-α （10 ng/mL）. Conclusion： A tight cross-regulation exists between ERK and PIMT in regards to their activation and expression during the EMT.

关 键 词：protein L-isoaspartyl O-methyltransferase （PIMT） breast cancer METASTASIS epithelial mesenchymal transition extracellularsignal-regulated kinase （ERK） siRNA 

分 类 号：Q26[生物学—细胞生物学] Q51