| Background:Hepatocellular carcinoma(HCC)is a common malignant tumor with high mortality in China.The most important cause is the infection of hepatitis B virus(HBV).It’s necessary to work on the carcinogenic mechanism of HBV and the characteristics of HBV-related HCC.Genome-wide association study(GWAS)finds many HBV and HCC susceptibility-related SNPs through high-throughput SNP detection,which contributes to genetic understanding of the disease.In the post-GWAS era,the in-depth data mining including the functional research of SNPs has become the main direction.Our previous study found that the genotypes of six SNPs(rs1419881,rs7453920,rs3997872,rs7768538,rs2275959)were correlated with the overall survival of HBV-related HCC patients.This study aims to screen functional genes by combining clinical pathological features and bioinformatics methods to perform functional analysis of these prognosis-related SNPs.Materials and Method:1.Retrospectively analyze the clinical and pathological data of the 330 patients included in the previous study.The relationship between the genotypes of SNPs located in the human leukocyte antigen(HLA)region and the index of immune inflammation(neutrophil lymphocyte ratio)was analyzed to investigate the relationship among SNP,immune response,systemic inflammatory response,and survival of HCC.2.The clinical and pathological data of 344 HCC patients undergoing radical hepatectomy were retrospectively analyzed.The relationship between the ratio of baseline neutrophil lymphocyte ratio and survival and recurrence was analyzed,and the effect of genetic factors on immune response was preliminarily explored.3.According to bioinformatics methods,search for genes related to prognosis-related SNPs and preliminary screening for potential functional genes based on literature searches.4.Immunohistochemical methods were used to monitor the expression of the selected genes in hepatocellular carcinoma tissues and paracancerous tissues,and to analyze the correlation of expression levels with SNP genotypes and prognosis of HCC.5.Validate relevant functions of SNP potential functional gene in liver cancer cell lines.Result:1.The genotypes of rs7453920 G>A,rs3997872 T>A,rs7768538 A>C located in the HLA gene region is related to the level of neutrophil/lymphocyte ratio(NLR),and NLR is an independent predictor of overall survival.The absence of the minor allele of rs7453920,rs3997872,rs7768538 promotes systemic inflammatory responses and has an adverse effect on the OS of HBV-related HCC patients.2.The baseline NLR levels after radical surgery are still closely related to the prognosis of HCC patients,and are related to the early recurrence and late recurrence of HCC,suggesting that the balance of immune response and systemic inflammation may be affected by genetic factors.3.According to bioinformatics methods,11 genes(ZNF703,EGFL8,RNF5,PBX2,BRF2,BTNL2,SLC39A7,MDC1,TUBB,VARS2,AIF1)may have potential functions in liver cancer.Previous studies have found that these genes have functions in malignant tumors.4.Immunohistochemical analysis revealed that the expression of MDC1 is associated with the prognosis of HCC,and is closely related to the SNP genotypes,and may be a potential functional gene of rs 1419881.5.In Huh7 hepatoma cells,MDC1 expression was significantly reduced after siRNA interference,suggesting that MDC1 can promote the proliferation of hepatoma cells.Conclusions:In the post-GWAS era,there is no best method for the study of SNP function.Our study found that the genotypes of some SNPs located in the HLA gene region,may be related to systemic inflammatory response,and this correlation can be reflected by NLR.rs1419881 may affect the prognosis of HCC by affecting the expression of MDC1 gene.The specific mechanism is unknown,and more in-depth research is of great significance. |
