转化生长因子调控表皮生长因子受体在雄激素非依赖型前列腺癌细胞中表达的意义

目的 :探讨转化生长因子 (TGF)α对前列腺癌雄激素非依赖型细胞系中表皮生长因子受体 (EGFR)表达的调控。　方法 :采用逆转录 多聚酶链式反应和Western印迹法对TGFα刺激前列腺癌雄激素非依赖型细胞系PC3、ARCaP后EGFRmRNA表达及其蛋白水平进行定量分析。　结果 :TGFα引起PC3、ARCaP的EGFRmRNA表达升高 ,分别为 5 .0 1± 0 .4 5和 9.0 5± 0 .6 3,明显高于对照组 (P <0 .0 5 )。PC3细胞系TGFα治疗后EGFR蛋白水平为 2 .2 8±0 .5 3,明显高于对照组 (P <0 .0 5 ) ;而ARCaP细胞系TGFα治疗后EGFR仅为 1 .2 4± 0 .2 2 ,和对照组比较无差别 (P >0 .0 5 )。　结论 :TGFα可以明显提高前列腺癌细胞的EGFR表达量 ;TGFα EGFR自分泌环参与雄激素非依赖型前列腺癌的形成

Regulation of EGF-Receptor Expression by TGFα in Human Prostate Androgen-unresponsive Cancer Cells

OBJECTIVE: To elucidate the regulation of epidermal growth factor receptor (EGFR) expression by transforming growth factor (TGFalpha) and epidermal growth factor (EGF) in human prostate androgen-unresponsive cancer cells. METHODS: EGFR mRNA expression and its protein level were measured by means of RT-PCR and Western blot respectively in human prostate cancer androgen-unresponsive cell lines, ARCaP and PC3, all treated with exogenous TGFalpha. RESULTS: In the TGFalpha group, the levels of EGFR mRNA were 5.01 0.45 and 9.05 0.63 in PC3 and ARCaP respectively, significantly higher than in the control group (P < 0.05). The level of EGFR protein in PC3 treated with TGFalpha was 2.28 0.53, higher than in the control group (P < 0.05); however, the level of EGFR protein in ARCaP treated with TGFalpha was only 1.24 0.22, not different from the control (P > 0.05). CONCLUSION: TGFalpha/EGF-EGFR pathway serves as a key growth regulator in prostate cancer. TGFalpha, but not EGF, preferentially maintains an autocrine loop in human androgen-unresponsive prostate cancer.