表皮生长因子促进胰腺癌细胞侵袭和转移的实验研究

Role of Epidermal Growth Factor in Invasion and Metastasis of Pancreatic Cancer Cells

目的探讨表皮生长因子(epidermal growth factor,EGF)促进胰腺癌细胞侵袭和转移的分子机理。方法EGF对胰腺癌细胞系NOR-P1的增殖、黏附及侵袭能力的影响分别用WST-1细胞增殖实验、细胞黏附实验和Transwell体外侵袭实验检测;MMP-9和MMP-2的活性及表达分别用明胶酶谱分析和Western印迹、RT-PCR检测;NF-κB活性用凝胶电泳迁移实验检测。结果EGF能够明显促进胰腺癌细胞的侵袭能力,但对胰腺癌细胞的黏附力及增殖并无明显影响;EGF明显上调胰腺癌细胞的NF-κB和MMP-9的活性及表达,但对MMP-2活性及表达无影响;NF-κB抑制物四氢化吡咯二硫代氨基甲酸盐(PDTC)能够明显抑制EGF所诱导的NF-κB活性,同时也抑制EGF所诱导的MMP-9表达及胰腺癌细胞的侵袭力。结论EGF通过活化NF-κB促进胰腺癌细胞的MMP-9的表达和侵袭力,采用NF-κB抑制剂PDTC阻断NF-κB通路能够降低胰腺癌细胞的侵袭力。

Objective Overexpressions of epidermal growth factor （EGF） and EGF receptor have been associated with progression and invasive phenotype of pancreatic cancer. However, the underlying molecular mechanism by which EGF worked in pancreatic cancer cells has not been completely understood. In this study, effect of EGF on the invasion and metastasis of pancreatic cancer cells and its regulatory mechanism were investigated. Methods The effects of EGF on the proliferation, adhesion and invasion of pancreatic cancer cells were detected by WST-1 proliferation assay, adhesion assay and invasive assay, respectively, The activity and expression of MMP-2 and MMP-9 were examined by zymography, Western blot and RT-PCR, respectively. The activity of NF-κB was examined by EMSA, Results EGF could significantly promote the invasiveness of pancreatic cancer cells but did not affect cell proliferation or adhesion, The expressions of NF-κB and MMP-9 were significantly increased by EGF, but EGF did not affect the activity and expression of MMP-2, Furthermore, EGF stimulated the NF-κB binding activity. Pretreatment with NF-κB inhibitors, pyrrolidine dithiocarbamate （PDTC）, could significantly inhibit the activity of NF- κB induced by EGF, Meanwhile, the EGF-induced expression and activity of MMP-9, as well as cell invasiveness were also inhibited by NF-κB inhibitor, Conclusion EGF could increase the expression and promote the invasiveness of MMP-9 via the activation of NF-κB in pancreatic cancer cells, which implies that NF-κB inhibitant, such as PDTC, may diminish the invasiveness of pancreatic cancer cells