Objective: To study the expression and effect of small nuclear ribonucleoprotein-associated protein B (SNRPB) on proliferation and metastasis of liver cancer tissues and cells. Methods: The bioinformatics database starBase v3.0 and GEPIA were used to analyze the expression of SNRPB in liver cancer tissue and normal liver tissue, as well as the survival and prognosis of liver cancer patients. The expression of SNRPB mRNA and protein in liver cancer cell lines were analyzed by qRT-PCR and Western blot. RNA interference technique (siRNA) was used to determine SNRPB protein expression down-regulation. The proliferation effect on hepatocellular carcinoma cells was observed by MTT assay. Transwell invasion and migration assay was used to detect the changes in the metastatic ability of liver cancer cells after SNRPB down-regulation. Western blot was used to detect the changes of epithelial mesenchymal transition (EMT) markers in liver cancer cells after down-regulation of SNRPB expression. Data were compared between two groups and multiple groups using t-test and analysis of variance. Results: The expression of SNRPB was significantly higher in liver cancer tissue than normal liver tissue, and its expression level was correlated with the prognosis of liver cancer patients. Compared with the immortalized hepatocyte LO(2), the expression of SNRPB was significantly increased in the liver cancer cells (P < 0.01). siRNA-SNRPB had significantly inhibited the expression of SNRPB mRNA and protein in liver cancer cells. MTT results showed that the absorbance value was lower in SNRPB knockdown group than negative control group, and the difference at 96 h after transfection was most significant (P < 0.01). Transwell assay results showed that compared with the negative control group, the SNRPB knockdown group (MHCC-97H: 121.27 ± 8.12 vs. 46.38 ± 7.54; Huh7: 126.50 ± 6.98 vs. 41.10 ± 8.01) invasion and migration (MHCC-97H: 125.20 ± 4.77 vs. 43.18 ± 7.32; Huh7: 132.22 ± 8.21 vs. 38.00 ± 6.78) ability was significantly reduced (P < 0.01) in liver cancer cells. Western blot showed that the expression level of epithelial phenotype marker E-cadherin was decreased after down-regulation of SNRPB, while the expression levels of mesenchymal phenotype markers N-cadherin and vimentin was increased, suggesting that down-regulation of SNRPB inhibited EMT in liver cancer cells. Conclusion: SNRPB expression is significantly increased in liver cancer tissues and cells, and it is involved in regulating the proliferation, metastasis and EMT of liver cancer cells.
目的： 研究小核糖体核蛋白B（SNRPB）在肝癌组织及细胞中的表达情况，以及SNRPB对肝癌细胞增殖与转移的作用。 方法： 通过生物信息数据库starBase v3.0和GEPIA分析SNRPB在肝癌组织和正常肝脏组织中的表达，并进行肝癌患者预后生存分析；qRT-PCR和蛋白质印迹法（Western blot）分析SNRPB mRNA和蛋白在肝癌细胞系中的表达；利用RNA干扰技术（siRNA）下调SNRPB蛋白的表达，通过MTT实验观察其对肝癌细胞增殖的作用；Transwell侵袭迁移实验检测下调SNRPB后肝癌细胞转移能力的变化；利用Western blot技术检测下调SNRPB表达后肝癌细胞上皮-间质转化（EMT）标志物的改变。数据两组间比较采用t检验，多组间比较采用方差分析。 结果： SNRPB在肝癌组织中的表达明显高于正常肝脏组织，且其表达水平并与肝癌患者预后相关。与永生化肝细胞LO(2)相比，SNRPB在肝癌细胞系中的表达显著升高（P值均< 0.01）。siRNA-SNRPB显著抑制肝癌细胞内SNRPB mRNA和蛋白表达。MTT结果显示SNRPB敲低组的吸光度值较阴性对照组降低，其中转染96 h的差值最显著（P值均< 0.01）。Transwell实验结果显示，与阴性对照组相比，SNRPB敲低组肝癌细胞的侵袭（MHCC-97H：121.27±8.12对比46.38±7.54；Huh7：126.50±6.98对比41.10±8.01）和迁移（MHCC-97H：125.20±4.77对比43.18±7.32；Huh7：132.22±8.21对比38.00±6.78）能力显著降低（P值均< 0.01）。Western blot显示下调SNRPB后上皮表型标志物E-钙黏蛋白表达水平下降，间质表型标志物N-钙黏蛋白和波形蛋白的表达水平上升,表明下调SNRPB抑制肝癌细胞EMT。 结论： SNRPB在肝癌组织及细胞中表达显著升高，并且参与调控肝癌细胞的增殖与转移及EMT。.
Keywords: Epithelial-mesenchymal transition; Hepatocellular carcinoma; Metastasis; Proliferation; Small nuclear ribonucleoprotein polypeptides B.