The Research On The Role Of PI3K/Akt Signal Transduction Pathway In Adjustment Of TGF-beta1 Expression And Cell Vitality Induced By Endothelin In Malignant Melanoma In Vitro

PartⅠThe role of endothelins in TGF-β1 expression and growth effect in malignant melanoma in vitroObject To explore the role of endothelin1,3 in TGF-β1 expresssion on protein secretion and mRNA level and the relationship to MM cell growth effect in cell lines A375 and SK-Mel-1.Methods MM cells stimulated by endothelin1,3 on different concentration, MTT method measure the growth effect in two MM cell lines;RT-PCR and ELISA technique was used to detect the TGF-β1 expression simulated by ET-1,ET-3, or combination with BQ123,BQ788,and LY294002.Results ET-3 promoted cell growth both in A375 and SK-Mel-1 cell lines and show the concentration-dependent. ET-1 inhibits cell growth in A375 but not in SK-Mel-1; ET-1 significantly up-regulates the TGF-β1 expression both on protein and mRNA, ET-3 show oppositely effects. Combination treated with BQ123, BQ788, and LY294002 show block effect of ET stimulation to MM cellsConclusion melanoma cells growth was suppress by TGF-β1 induced by ET-1; ET-3 inhibited TGF-β1 expression through activation of PI3K/Akt pathway; the effect of cell growth inhibition induced by TGF-β1 showed a diversity phenomenon between melanoma cell lines. Endothelins; phosphor-Akt; PI3K/Akt pathway; apoptosis; Cisplatin PartⅢEndothelin1 promotes the over-expression of phospho-Smad3 through ETRA pathway in melanomaObject To investigate the roles of ET1, ET-3 and combination treatment with BQ123, BQ788 in overepression of phospho-Smad3 protein in melanoma cells.Methods Westrn blot technique was applied to detect the expression of phosphor-Smad3 under the ET-1, ET-3stimulation or conjoined treatment with BQ123 and BQ788 .Result ET-1 induced phosphor-Smad3 over-expression significantly, and BQ123 but not BQ788 inhibited this phenomenon. Oppositely, ET-3 suppress the expression of it comparing with control.Conclusion ETRA but not ETRB mediated the over-expression of phosphor-Smad3 induced by endothelin in MM A375 cell line.