Regulation of EGF-receptor expression by TGFalpha in human prostate androgen-unresponsive cancer cells
Chen, W.; Yan, C.; Pu, J.; Hou, J.; Wen, D.; Guo, Z.
Zhonghua Nan Ke Xue 10(8): 595-597
2004
ISSN/ISBN: 1009-3591 PMID: 15362522 Document Number: 569231
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. 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. 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). 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.