Objective: To explore the characteristic genomics of syndrome of liver-kidney yin deficiency in peripheral blood mononuclear cells of hepatocellular carcinoma (HCC) patients.
Methods: HCC patients with or without syndrome of liver-kidney yin deficiency were enrolled into the experimental group and the control group, respectively; their gene expression profiles were evaluated by a whole-genome Affymetrix GeneChip Human Genome U133 Plus 2.0 Array. The differentially expressed mRNAs were then selected by Gene Ontology (GO) and pathway analyses, respectively. Based on the results of GO and pathway analyses, gene coexpression networks were built according to the normalized signal intensity of specifically expressed genes. Finally, the results from microarray were confirmed by real-time fluorescence quantitative polymerase chain reaction and Western blot methods.
Results: The results showed that a set of 615 mRNAs were differentially expressed in the HCC patients with syndrome of liver-kidney yin deficiency. By GO enrichment analysis, the genes for anti-apoptosis, regulation of cell cycle, transmembrane transport, etc. were up-regulated or down-regulated in the experimental group. Another functional analysis of mRNAs by KEGG revealed that 10 signal transduction pathways were up-regulated and 16 were down-regulated, such as antigen processing and presentation, cell cycle, and protein export. Based on the above results, we constructed coexpression networks to determine which genes may play pivotal role in HCC patients with syndrome of liver-kidney yin deficiency. Some critical genes, including SEC62 (SEC62 homolog (S. cerevisiae)), CCNB1 (cyclin B1) and BIRC3 (baculoviral IAP repeat-containing 3), which rank the top 3 in |δ normalized degree| were chosen. Of another 60 samples, we found that the mRNA expressions of SEC62, CCNB1 and BIRC3 were significantly lower in HCC patients with syndrome of liver-kidney yin deficiency than those without syndrome of liver-kidney yin deficiency (P<0.01). Also, the protein expressions of SEC62, CCNB1 and BIRC3 were significantly lower (P<0.01).
Conclusion: Gene chip technique allows rapid and high-throughput screening for different gene expression in HCC patients with or without liver-kidney yin deficiency syndrome. The results of this study further confirm the hypothesis on the essence of syndrome, namely, a kind of deviation from the normal state in multigene style on the levels of both mRNA and protein.