慢性乙型肝炎肝纤维化患者肝组织基因表达谱和功能分类

Genomic profile and functional characterization of liver fibrosis in patients with chronic hepatitis B

目的采用基因芯片技术分析与慢性乙型肝炎肝纤维化相关的基因表达谱。方法采用AffymetrixU133A基因芯片技术对139份不同纤维化Scheuer分期的肝组织,进行mRNA基因表达谱检测分析,并应用GeneSpring10软件系统行统计分析。结果 139份慢性乙型肝炎肝纤维化样本按S0-S4分期分为5组:(S0:48;S1:23;S2:37;S3:17;S4:14)。差异基因聚类分析显示肝纤维化分期不同,组间的基因表达也存在差异,提示基因表达谱与组织纤维化分期具有较好的一致性。S1-S4组分别与S0组比较,差异基因共有1451个(p≤5×10-6)。S4组与S0组比较,差异倍数大于2倍的上调差异基因共174个,下调差异基因共45个。在上调的174个基因中,从基因功能分类看,结构分子活性(包括细胞外基质,膜或胶原成分)相关基因改变最多为58个,占26.7%;其次是信号传导活性相关基因26个,占12.0%;第三是细胞黏附分子活性相关基因24个,占11.1%;以上3大类共占基因总数的49.8%。结论随着乙型肝炎肝纤维化程度进展,肝组织中大量结构分子,信号转导分子和细胞黏附分子活性相关的基因呈现活跃的表达上调,因而转录和翻译后产生出大量相应具有促纤维化形成活性的蛋白质和酶类。这些活性高度改变的基因是许多炎性反应、免疫反应和细胞增殖/凋亡信号通路的关键酶类和中间产物,诱发或加剧了肝纤维化的发生、发展。

Objective To analyze chronic hepatitis B-related fibrosis gene expression using GeneChip. Methods Liver biopsies were utilized in 139 CHB patients and pathological Scheuer stages were defined. The Affymetrix GeneChipTM Human Genome U133A microarray was used to establish the gene expression signature. Genomic profiles and data analysis were obtained through GeneSpring 10 software. Results Samples were clustered according to Scheuer＇s stage groups （S0： 48; SI ： 23; S2： 37; S3： 17- S4： 14）. Cluster analysis led to result supporting the conclusion that gene expression profiles robustly reflected the fibrosis classification. A Welch t-test, in order to find the significant differentially expressed genes among S0-S4 groups, generated a list of 1,451 genes （p≤5 x 10^-6）. Group-based comparisons for S4 versus S0, it showed over 2 times up-regulated genes （n = 174） and down-regulated genes（n = 45）. Among the 174 up-regulated genes, genes with function in the structural molecular activity were most frequently up-regulated （n = 58, 26.7 %）, and genes involved in signal transduction （n = 26, 12. 0%） or cell adhesion （n = 24, 11. 1%） were less commonly up regulated respectively. These three categories accounted for 49.8% of the total number of genes. Conclusion With the progress of hepatitis B- related liver fibrosis, a large number of structural molecular activity, signal transduction activity and cell adhesion activity- related genes upregulate significantly, thus produce generous proteins and enzymes related to fibrogenensis after transcription and translation. These highly altered genes of many inflammatory response, immune response and cell proliferation/apoptosis signaling pathways critical enzymes and intermediate products, induce or aggravate the development of liver fibrosis.