胃泌素及丙谷胺对胃癌细胞株MKN45增殖及EGF表达的影响

目的:观察五肽胃泌素(PG)及其受体拮抗剂丙谷胺(PGL)对人胃癌细胞株MKN45增殖及表皮生长因子(EGF)表达的影响。方法:MTT法检测人胃癌细胞株MKN45增殖;放射免疫法(RIA)测定表皮生长因子(EGF)的表达。结果:PG(10-6mol/L)明显促进人胃癌细胞株MKN45增殖,24、48h的促细胞增殖率分别为11.24%、17.63%,丙谷胺(2.0～10.0mmol/L)能阻断这一促增殖作用,并可剂量依赖性地抑制胃癌细胞的生长,且随作用时间延长而增强。同时,在胃癌细胞株MKN45培养液中可检测到EGF,且随培养时间延长EGF含量增加;PG(10-6mol/L)可显著增加MKN45培养液中EGF的含量,丙谷胺(6.0mmol/L)不仅明显阻断PG诱导的EGF增加,并且能够减少胃癌细胞MKN45培养液EGF的含量。结论:五肽胃泌素能促进胃癌细胞株MKN45增殖及EGF表达,而其受体拮抗剂丙谷胺不仅能阻断这一的促进作用,并可抑制胃癌细胞株MKN45增殖及EGF的表达。提示PG的促胃癌细胞增殖作用可能与促进EGF表达有关。

Effects of gastrin and Proglumide on cell proliferation and epidermal growth factor secretion in gastric cancer cell lines MKN45 in vitro

objective:To investigate the effects of pentagastrin(PG)and its receptor antagonist proglumide(PGL)on cell proliferation and secretion of epidermal growth factor(EGF)in MKN45 cell lines in vitro.Methods:Cell validity was assayed by MTT method.And the concentration of EGF was examined by radioimmunoassay(RIA).Results PG significantly stimulated cell proliferation at the concertration of 10-6 mol/L,and the rate of cell proliferation were 11.24% and 17.63% for 24,48h,respectively.PGL(2.0～10.0 mol/L)significantly not only blocked the pentagastrin-induced MKN45 cell proliferation,but also inhibited the proliferation of MKN45 cells dose-dependently in vitro.The inhibition of PGL on the proliferation of MKN45 cells at 48 hour was stronger than that at 24 hour.EGF could be found in cultured medium with MKN45 cells,and the concentration of EGF was increased with time.PG significantly increased the concentration of EGF at the concertration of 10-6 mol/L,while PGL(6.0 mmol/L)significantly not only attenuated the PG-induced EGF increase,but also reduced EGF auto-secretion in gastric cancer cell lines MKN45 in vitro.Conclusions:PG can promote the proliferation and EGF secretion of MKN45 cells,while PGL may inhibit the proliferation and EGF secretion,and block the effect of PG in MKN45 cell lines in vitro.Its mechanism may be due to promoting EGF secretion of gastric cancer cells.