HBx通过上调前列腺素E_2受体2的表达增强HL-7702肝细胞的侵袭能力

HBx Enhances the Invasion of HL-7702 Liver Cells Through Increasing Prostaglandin E2 Receptor 2 Expression

目的:以HL-7702肝细胞为研究对象,探讨HBx的表达对EPs的影响以及与侵袭转移的相关性。方法:建立表达HBx的HL-7702人正常肝细胞(HL-7702/HBx),采用HBxRNAi载体构建抑制HBx的HL-7702肝细胞株(HL-7702/HBx-siRNA),检测抑制HBx前后细胞培养上清PGE_2浓度的变化、细胞表达EPs mRNA和基质金属蛋白酶(MMPs)mRNA的变化,并进一步采用EP2-siRNA瞬时转染、Western-blot、明胶酶谱和Transwell小室等技术观察EP2表达的抑制对MMPs活性以及细胞侵袭和转移能力的影响。结果:与对照细胞相比,PGE_2、EP2和MMP-2的mRNA相对表达值在HL-7702/HBx细胞明显增高(P<0.05),分别为(123.9+9.9)Pg·mL^(-1)、(0.445+0.025)Pg·mL^(-1)和(0.226+0.016)Pg·mL^(-1),在抑制HBx表达后则明显下调(P<0.05),分别为(78.0±5.9)Pg·mL^(-1)、(0.336+0.007)Pg·mL^(-1)和(0.117+0.012)pg·mL^(-1);对照细胞HL-7702的EP2表达抑制前后,MMP2活性、细胞侵袭和移动能力变化不明显;而HL-7702/HBx细胞的EP2表达受抑制后,其MMP2活性和细胞侵袭能力则明显下降(P<0.05),侵袭细胞数由(64.4+3.4)个/视野下降为(55.2+2.2)个/视野,细胞的移动能力变化不大。结论:HBx可以促进EP2表达和增加MMP2活性,并通过EP2上调HL-7702肝细胞的侵袭能力。抑制EP2表达可能对HBV感染的肝癌侵袭转移治疗研究具有潜在的应用价值。

Objective： To investigate the impact of HBx on EP expression in HL-7702 cells and its correlation with invasion and metastasis. Methods： Based on established HL-7702 cells with HBx expression （ HL-7702/HBx ）, HBx RNAi vector was used to construct the HL-7702 cell line with inhibited HBx expression （ HL-7702/HBx-siRNA ） and measured the change of the PGE2 concentration in the supernatant expression of EPs and MMPs mRNA in this cell line, as well as the control cell lines. The change of MMPs activities of invasion and metastasis upon inhibition of EP2 expression using the methods of transient transfection of EP2-siRNA, West- ern-blot, Gelatin zymography, and Transwell chamber technology were also detected. Results： （1） PGE2 concentration, EP2, and MMP2 relative expression in HL-7702/HBx ceils significant increased （ P 〈 0.05 ） compared with the control cells. The values were 123.9 ± 9.9 pg/mL, 0.445± 0.025 pg/mL, and 0.226 4- 0.016 pg/mL, respectively. Consequently, the values decreased after the HBx expression was inhibited （ P 〈 0.05 ）, and the resulting values were 78.0 4- 5.9 pg/ml, 0.336 4- 0.007 pg/mL, and 0.117 4- 0.012 pg/mL. （2） After EP2 expression was inhibited, the MMP2 and MMP9 activity, the ability of cell invasion, and migration were not changed in HL-7702 cells, however, the MMP2 activity, and the cell invasion ability decreased significantly in HL-7702/HBx cells （ P 〈 0.05 ）. The amount of invasion cell was from 64.4 4- 3.4/field to 55.2 4- 2.2/field. Conclusion： HBx could promote the EP2 expression and MMP2 activity and may increase the invasion ability of HL-7702 cells by upregulating the EP2 expression. The inhibition of EP2 is of potential value for the treatment research on invasion and metastasis of liver cancer with HBV infection.