下调AnnexinA2的表达在促前列腺癌进展中的作用

Down-regulating AnnexinA2 Expression could Promote Invasion and Metastasis of Prostate Cancer

目的探讨AnnexinA2(ANXA2)的异常表达在前列腺癌(prostate cancer,PC)进展中的作用机制。方法采用免疫组织化学化检测ANXA2在85例PC标本中的表达水平,Western blot检测不同转移潜能的前列腺癌细胞LNCaP、C4-2B和PC-3、PC-3M中ANXA2的表达水平;siRNA技术干扰PC-3细胞中ANXA2表达后,MTT检测细胞增殖,Western blot检测MMP-2、MMP-9表达水平的改变,Transwell小室和划痕试验检测PC-3细胞体外侵袭能力及迁移能力的变化。结果 ANXA2阳性率在Gleason评分为5~6、7、8~10分中的阳性率分别是77.5%(31/40)、58.3%(21/36)、11.1%(1/9),三者之间表达差异有统计学意义(P<0.05),随着前列腺癌细胞转移潜能升高而ANXA2表达水平依次降低(P<0.01);siRNA技术干扰AnnexinA2表达后,PC-3-ANXA2-siRNA生长速度增加(P<0.05),Western blot检测到PC-3-ANXA2-siRNA细胞的ANXA2表达水平明显降低,而MMP-2、MMP-9表达水平上调,Transwell小室和划痕实验分别发现PC-3-ANXA2-siRNA细胞体外侵袭及迁移能力增加。结论下调AnnexinA2的表达能够促进前列腺癌进展,机制上可能是通过上调MMP-2和MMP-9的表达来实现的。

Objective To analyze the mechanism of AnnexinA2 abnormal expression in invasion and metastasis of prostate cancer(PC). Methods A total of 85 PC specimens were paraffin-embedded and confirmed pathologically. AnnexinA2 expression in these specimens was determined by immunohistochemical staining. Western blot assay was conducted to detect AnnexinA2 expression in LNCaP and PC-3 with low metastasis potency, as well as and C4-2B and PC-3M with high metastasis potency. After siRNA was successfully performed in PC-3 cells to down-regulate AnnexinA2 expression, cell proliferation assay was performed by MTT method. Expression of MMP-2 and MMP-9 were detected by Western blot. Invasive abilities of PC-3 were detected by Transwell cabinet test in vitro. Migration abilities of PC-3 cells were detected by scratch test. Results The positive rates of AnnexinA2 expression were 77.5%(31/40), 58.3%(21/36), 11.1%(1/9) in the cases of Gleason scores 5~6, 7 and 8~10 in PC, respectively, with significant difference(P< 0.05). AnnexinA2 expression in C4-2B and PC-3M groups with high metastasis potency were lower than those in LNCaP and PC-3 groups with low metastasis potency(P<0.05). After siRNA was successfully performed in PC-3 cells to down-regulate AnnexinA2 expression, the growth speed in PC-3-ANXA2-siRNA cells was faster than those in PC-3, PC-3-Lip and PC-3-empty vector cells(P<0.05). AnnexinA2 expression in PC-3-ANXA2-siRNA cells was decreased while the expression of MMP-2 and MMP-9 were increased. Invasive ability of PC-3-ANXA2-siRNA cells detected by Transwell cabinet test was increased in vitro, and migrate abilities of PC-3-ANXA2-siRNA cells detected by scratch test was increased in vitro. Conclusion Down-regulating AnnexinA2 expression could promote invasion and metastasis of PC by up-regulating MMP-2 and MMP-9 expression.