Over-expression of caveolin-1 inhibits proliferation and invasion of pancreatic carcinoma cells in vitro

Abstract

To investigate the effects of caveolin-1 on the biologic behavior of pancreatic carcinoma cell line panc1 cells in vitro. Eukaryotic expression vectors containing human caveolin-1 gene was stably transfected into panc1 cells with Lipofectamine2000. The clones stably overexpressing caveolin-1 were identified by real-time PCR and Western plotting. The cell growth activity was examined by MTT assay. Anchorage-independent growth was detected by colony formation assay in soft agar. Flow cytometry was used to analyze the cell cycle and apoptosis. Cell invasion assay was used for evaluating cell invasion capacity. The relative phosphorylation level of EGFR, c-Raf, Mek, Erk, p38 and SAPK/JNK were detected by Western blotting. Three transfected cell clones overexpressing caveolin-1 were obtained. Comparing with the panc1 cells, the transfected cells exhibited a slower growth rate and formed fewer colonies in soft agar. The results of flow cytometry showed that over-expression of caveolin-1 resulted in the cell cycle arrest at G(0)/G(1) phase and increased the apoptotic cell fraction. Cell invasion assay showed that overexpression of caveolin-1 significantly inhibited the panc1 cell invasion. Western blotting results showed that overexpression of caveolin-1 reduced the phosphorylation of EGFR, c-Raf, Mek and Erk while did not affect the activity of p38 and SAPK/JNK. Over-expression of caveolin-1 inhibits the growth and invasion of pancreatic carcinoma cells in vitro. These phenotypes may be correlated with the inhibition of EGFR-c-Raf-Mek-Erk signaling pathway.