酪酪肽对胰腺癌Miapaca-2细胞凋亡的影响

目的 观察酪酪肽(PYY)对体外培养的胰腺癌Miapaca-2细胞凋亡的影响。方法 不同浓度(0.01、0.005、0.0025、0.00125 mmol/L) PYY分别作用于体外常规培养的Miapaca-2细胞48 h后,流式细胞仪检测细胞凋亡率、细胞周期;RT-PCR法检测Survivin mRNA,Western blotting法检测Survivin、Caspase-3蛋白的表达。结果 PYY处理48 h后细胞凋亡率明显升高,并呈浓度依赖性;G₀/G₁期细胞数明显增多,S、G₂/M期细胞数明显减少,G₁期前出现亚二倍体凋亡峰;PYY明显抑制Survivin蛋白和mRNA表达(P<0.01),上调Caspase-3蛋白表达(P<0.01)。结论 PYY能诱导胰腺癌Miapaca-2细胞凋亡,参与细胞周期调控,其机制可能与抑制Survivin蛋白和mRNA表达、上调Caspase-3蛋白表达有关。

Effects of peptide YY on apoptosis of human pancreatic cancer cell line Miapaca-2 in vitro

Objectives To observe the effects of peptide YY(PYY)on inducing apoptosis of human pancreatic cancer cell line Miapaca-2. Methods The pancreatic cancer cell line Miapaca-2 was treated with PYY of different concentrations(0.01, 0.005, 0.0025 and 0.00125 mmol/L) for 48 h.The apoptosis and cell cycle were evaluated by flow cytometry, the expression of survivin mRNA was detected with RT-PCR, and the expressions of survivin and Caspase-3 protein were detected with Western blotting. Results After intervention with PYY for 48 h, celluar apoptosis rate was significantly increased in a dose-dependent manner. The cells of G₀/G₁ stage were significantly increased, but the cells of S and G₂/M stages were significantly decreased. The hypodiploid apoptotic peak before the G₁ stage was detected. PYY inhibited survivin protein and survivin mRNA expressions but increased Caspase-3 protein expression notably in a dose dependent manner(P<0.01). Conclusion PYY can induce apoptosis in a dose-dependent manner. PYY maybe block cell cyclein G₀/G₁ stage, downregulate survivin mRNA and protein expressions, increase Caspase-3 protein expression and finally induce apoptosis.