Comprehensive analysis of genomic and immunological profiles in Chinese and Western hepatocellular carcinoma populations

In this study, we explored the genomic and immune cell infiltration profiles among four distinct Hepatocellular carcinoma (HCC) types. This study included 100 patients (all tumors and adjacent liver tissues received WES sequencing) with HCC from the West China Hospital (WCH) and patients were divided into WCH-HBV-HCC group and WCH-NonHBV-HCC group. Additionally, this study included 106 HBV-related HCC (TCGA-HBV-HCC) and 69 alcoholic HCC (TCGA-Alcol-HCC) patients from the TCGA. We analyzed the high-frequency gene mutation, copy number variation (CNV), mutation spectrum, signatures and immune cell infiltration of these four groups. This study showed significant differences in gene mutation and CNV level among four HCC groups. Compared to genomic level, there is no significant difference between TCGA-HBV-HCC and TCGA-Alcol-HCC groups in fractions of tumor-infiltrating immune cells. According to the status of immune cell infiltration, patients were classified into immune-HIGH, immune-MIX and immune-LOW group, respectively. In the WCH-HBV-HCC and TCGA-HBV-HCC groups, more patients in the Immune-LOW group had TP53 mutation. Except for TP53, neither the other gene mutation nor tumor mutation burden was found to be associated with immune cell infiltration in the WCH-HBV-HCC, TCGA-HBV-HCC and TCGA-Alcol-HCC groups. In the CNV level, we found that samples with low immune infiltrate had higher number of deleted or amplified genes in the TCGA-HBV-HCC and TCGA-Alcol-HCC groups. We found comprehensive genomic heterogeneity among four HCC groups. The total gene CNV level, not the mutational burden of HCC, is associated with immune cell infiltration in HCC. TP53 mutation may injury the immune response of the HBV-related HCC.