CIP2A在不同肝病组织中表达及其协同表达基因的生物信息学分析

Expression of CIP2A in different liver disease tissues and bioinformatics analysis of CIP2A co-expressed genes

目的分析蛋白磷酸酶的癌性抑制因子(CIP2A)在不同肝病组织中表达,探索CIP2A协同表达基因网络中的潜在干预靶点。方法采用组织芯片免疫组织化学染色明确CIP2A在不同肝病组织中的表达,应用权重基因共表达网络分析(WGCNA),探索CIP2A基因同肝细胞癌差异表达基因的基因模块之间的关系,在DAVID数据库中进行相关功能富集分析及信号转导通路富集分析。结果组织芯片上60例肝细胞癌组织标本中,49例肝癌组织中CIP2A蛋白表达阳性或强阳性,阳性率为81.67%,7例肝硬化组织标本中有2例间质纤维明显增生的肝组织,可见CIP2A蛋白在肝细胞胞浆中存在弱阳性表达,阳性率为28.56%,而5例正常肝脏组织、8例慢性活动性肝炎组织标本中均未见CIP2A蛋白阳性表达。肝癌组织中CIP2A阳性率表达率明显高于肝硬化组织、慢性活动性肝炎组织及正常肝组织,差异有统计学意义(P<0.05)。CIP2A在晚期肝癌(Ⅲ～Ⅳ级)阳性表达率为88.89%(16/18),在早中期(Ⅰ～Ⅱ级)阳性表达率为42.86%(18/42),晚期肝癌组织中CIP2A阳性率表达率明显高于早中期肝癌组织,差异有统计学意义(P=0.05)。权重基因共表达网络分析(WGCNA)结果显示,CIP2A与MEturquoise模块中其他438个基因密切相关,通过计算两两之间的Pearson相关系数,在36种相关性最显著的基因中,CIP2A与其他大部分基因(31/35,88.6%)的相关系数>0.4。KEGG通路富集分析结果提示,与CIP2A密切相关基因集中在3条信号通路,包括细胞周期、DNA复制及p53信号通路。GO生物学功能通路富集分析显示,与CIP2A密切相关基因主要集中在15种生物学功能通路,包括细胞分裂、核有丝分裂、DNA复制等。结论 CIP2A与肝癌的发生发展密切相关,涉及多个生物学过程和信号转导通路。

Objective To analyze the expression of CIP2A in different liver diseases, and to explore potential intervention targets in CIP2A co-expression gene network. Methods Immunohistochemical staining of tissue microarray confirmed the expression of CIP2A in different liver diseases. Weighted gene co-expression network analysis(WGCNA) was applied to explore the relationship between CIP2A gene and the gene modules of differentially expressed genes in hepatocellular carcinoma, and the GO and KEGG pathway enrichment analysis was conducted with DAVID database. Results Of 60 cases of hepatocellular carcinoma tissue specimens, 49 cases whose CIP2A protein expression were positive, or strong positive, overall positive rate was 81.67%;among 7 cases of cirrhosis of the liver tissue samples there were 2 cases of hyperplasia with interstitial fibers being obviously visible;CIP2A proteins in the liver tissue of weakly positive expression is found in the cytoplasm of liver cells, positive rate was 28.56%;and 5 cases of normal liver tissue, 8 cases of chronic active hepatitis CIP2A protein positive expression was not found in the tissue samples. The expression rate of CIP2A in liver cancer tissues was significantly higher than that in cirrhotic tissues, chronic active hepatitis tissues and normal liver tissues, and the difference was statistically significant(P<0.05). CIP2A in advanced liver cancer(Ⅲ-Ⅳ) the positive expression rate was 88.89%(16/18), in the early and middle stage liver cancer(Ⅰ-Ⅱ) positive expression rate was 42.86%(18/42), advanced liver cancer tissues CIP2A positive expression rate is significantly higher than early metaphase cancer of the liver tissue, difference was statistically significant(P=0.05). WGCNA analysis show that CIP2A was closely related to 438 other genes in MEturquoise module. By calculating Pearson correlation coefficient, among the 36 genes with the most significant correlation, the correlation coefficient between CIP2A and most other genes(31/35, 88.6%) is more than 0.4. The results of KEGG pathway enrichment analysis indicated that CIP2A genes were closely related to three signaling pathways, including cell cycle, DNA replication and p53 signaling pathways. The enrichment analysis of GO biological functional pathway showed that genes closely related to CIP2A were mainly concentrated in 15 biological functional pathways, including cell division, nuclear mitosis and DNA replication. Conclusion CIP2A is closely related to the occurrence and development of hepatocellular carcinoma, and it involves multiple biological processes and signal transduction pathways.