Smad4在人前列腺癌细胞系LNCaP和ARCaP中的差异表达及意义

目的:探讨TGF-β/Smads信号转导的核心Smad4在前列腺癌转移潜能获得中的作用及可能的机制。方法:用Millicell体外侵袭试验观察LNCaP和ARCaP系IF-11、IA-8细胞株转移潜能的差异情况,分别应用Western印迹法和逆转录PCR鉴定这3种细胞株中Smad4蛋白及mRNA的差异表达。结果:ARCaP系IF-11、IA-8细胞株的体外侵袭潜能明显高于LNCaP细胞(P<0.01);但Smad4蛋白在低转移潜能的LNCaP细胞中高表达,而在高转移潜能的IF-11、IA-8中表达缺失(P<0.01),Smad4 mRNA表达结果与蛋白一致。结论:Smad4在转移潜能不同的前列腺癌细胞系间存在差异表达,Smad4表达缺失可能是晚期前列腺癌发生侵袭转移的机制之一。

Expression of Smad4 in Prostate Cancer LNCaP and ARCaP Cell Lines with Different Metastatic Potentials and Its Significance

Objective： To observe the expression of Smad4, the core of TGF-β/Smads signal transduction pathway in different prostate cancer cell lines, and explore their molecular mechanism of bone metastatic potential. Methods： The Millicell polycarbonate filter coated with matrigel was used to confirm the invasive potency of LNCaP and ARCaP cell lines （ IF11 and IA8 ）. The expressions of the Smad4 protein and mRNA in these prostate cancer cells with different metastatic potentials were detected by Western blotting and RT- PCR, respectively. Results ： ARCaP cell lines （ IF11 and IA8） exhibited a stronger potency of invasion than LNCaP （P 〈 0.01 ）. The Smad4 protein and mRNA highly expressed in the LNCaP cell line that was well-known with a low metastatic potential, but not in the ARCaP （IF11 or IA8） cells with high metastatic potentials （P 〈 0.01 ）. Conclusion： Smad4 expresses differently in LNCaP and ARCaP cell lines with different metastatic potentials and, as a tumor suppressive gene, its deficient expression may play an important role in the invasion and metastasis of advanced prostate cancer.