微小RNA-133a在肝细胞癌组织的表达及其作用机制

The expression of microRNA - 133a in hepatocellular carcinoma tissue and its contribution to the regulation of biological function in human hepatocellular carcinoma cell line

目的观察微小RNA（miRNA，miR）-133a在肝细胞癌组织中的表达以及对肝癌细胞生物学行为的影响。 方法收集15例患者肝癌组织和癌旁组织，定量聚合酶链反应（PCR）检测miR-133a的表达。采用细胞增殖实验、细胞周期测定、划痕实验以及侵袭实验观察miR-133a过表达对肝癌细胞株Huh7的细胞生物学行为的影响。 结果与癌旁组织比较，miR-133a在肝癌组织中的表达水平显著下降，差异有统计学意义（0.40±0.17比1.10±0.32，P＝0.000）；与正常肝细胞株LO2比较，在肝癌细胞株HepG2和Huh7中miR-133a的表达显著下调，差异有统计学意义（1.00比0.20±0.11比0.28±0.09，P＝0.000）；进一步构建miR-133a过表达Huh7细胞株，细胞增殖实验结果表明，细胞培养36、48、72 h，过表达miR-133a的Huh7细胞增殖能力显著低于对照组，差异有统计学意义（0.40±0.03比0.55±0.03；0.44±0.02比0.66±0.02；0.64±0.04比1.14±0.03，P＝0.000）；细胞周期分析，过表达miR-133a的Huh7细胞分裂阻滞在G1期（41.69±1.22比54.23±4.35，P＝0.000）；划痕实验显示，过表达miR-133a的Huh7细胞较对照组细胞的迁移能力显著下调，48 h划痕距离百分比分别为（80±5）%和（50±12）%，差异有统计学意义（P＝0.016）。对照组细胞与过表达miR-133a的Huh7细胞侵袭能力差异无统计学意义（P＝0.404）。 结论miR-133a在肝癌肿瘤组织中低表达，且其表达与肿瘤细胞株增殖和迁移能力的改变有关，提示miR-133a参与调节肝癌细胞的生物学行为。

Objective To investigate the expression of microRNA （miRNA, miR） - 133a in hepa- tocellular carcinoma （HCC） tissues and its contribution to the regulation of biological function in HCC cell line Huh7. Methods The expression of miR - 133a in HCC tissues and adjacentnon - tumor liver tissues was detected by real -time quantitative polymerase chain reaction （Real -time PCR）. The methyl thiazol tetrazolium （MYr） assay, scrape assay and Transwell assay were used to investigate the contribution of miR - 133a on biological behaviors of HCC cells. Results The expression of miR - 133a was significantly down - regulated in HCC tissues as compared with the adjacent non - tumor liver tissues （0. 40 ± 0. 17 vs. 1.10 ±0. 32, P =0. 000）, Also miR - 133a level was significantly decreased in HCC cell lines relative to the normal hepatic cell line, L02 （0.40 ±0. 17 vs. 1.10 ±0. 32,P =0. 000）. The MTT cell proliferation experiment showed that the proliferation rate of forced expression miR - 133a group was lower than the con- trol after cultured for 36, 48, 72 h （0. 40 ± 0. 03 vs. 0. 55 ± 0. 03 ; 0.44 ± 0. 02 vs. 0. 66 ± 0. 02 ; 0. 64 ± 0. 04 vs. 1.14 ±0. 03 ,P =0. 000）. Cell cycle analysis revealed that forced expression miR- 133a Huh7 cells were arrested in G1 phase （41.69 ± 1.22 vs. 54. 23 ±4. 35, P =0. 000）. In wound healing assay, the number of Huh7 cells was significantly decreased after transfection of miR - 133a （P = 0. 016） , while the invasive ability of Huh7 cells had no significant difference after transfection of miR - 133a. Conclusion The expression of miR - 133a in HCC tissues and HCC cell lines was down - regulated. Forced expression of miR- 133a in HCC cell lines significantly inhibited cell proliferation and migration, suggesting that abnormal expression of miR - 133a in HCC could be involved in the regulation of the tumor biological behaviors and contribute to the tumor progression.