TGFα和EGF对前列腺癌细胞系EGFR表达的调控作用

Regulation of EGF-receptor expression by TGFα and EGF in human pros tate cancer cells

目的 探讨转化生长因子 (TGF)α和表皮生长因子 (EGF)对前列腺癌细胞系中表皮生长因子受体 (EGFR)表达的调控作用。 方法 采用RT PCR和Western印迹法分别对TGFα和EGF刺激前列腺癌细胞系LNCaP、PC3、ARCaP后EGFRmRNA表达及其蛋白水平进行定量分析。 结果 EGF引起前列腺癌细胞系LNCaP、PC3、ARCaP的EGFRmRNA升高 2～ 5倍 ,TGFα引起各细胞系EGFRmRNA升高 2～ 10倍。TGFα使各细胞系EGFR不同程度升高 ;EGF处理的LNCaPEGFR蛋白水平略升高 ,PC3、ARCaPEGFR蛋白水平降低。 结论 TGF/EGF EGFR通路在前列腺癌发生发展中起重要作用 ;非依赖型前列腺癌中TGFα EGFR自分泌环的作用可能强于EGF

Objective To elucidate the regulation of e pidermal growth factor receptor (EGFR) expression by transforming growth factor (TGF)α and epidermal growth factor (EGF) in human prostate cancer cells. Methods EGFR mRNA expression and its protein level were measur ed by means of RT-PCR and Western blot respectively in three human prostate can cer cell lines,the androgen-responsive (LNCaP) and the nonresponsive (ARCaP and PC3), all being treated with exogenous EGF or TGFα. Results TGFα enhanced EGFR mRNA two-to tenfold in all three cell lines, whereas EGF increased EGFR mRNA two-to sixfold.In all the three cell lines, TGFα induc ed total EGFR protein levels were higher than EGF. Conclusions These data indicate that TGFα/EGF-EGFR path-way serves as a key growth regulator in prostate cancer.TGFα, but not EGF, would preferentially maintain an autocrine loop in human androgen-nonresponsive prostate cancer.