关键词: 肝细胞癌, FAM72基因家族, 预后, 免疫浸润, 生物信息学分析

Abstract: Objective To analyze the expression, prognostic and immune infiltrationroles of FAM72 gene family （FAM72s） in hepatocellular carcinoma （HCC）. Methods TCGA was used to analyze the expression of FAM72s in patients with HCC, the differences among different clinical characteristics, and independentprognostic values. The relationships of FAM72s expression and overall survival （OS） were assessed using TCGA and Kaplan-Meier plotter. STRING was used to detect the protein-proteininteraction （PPI） networks forFAM72s. The relationship of FAM72s expression and immune infiltration was performed by the ssGSEA. We used GEPIA to evaluate the correlation of FAM72s expression with biomarkers of immune cells and immune checkpoints in HCC. Results The expressions of FAM72A-D in HCC were significantly increased compared with those in normal liver tissues （P<0.05）. The OS in the high FAM72A-D expression group were shorter than those in the low expression group （P<0.05）. Univariate/multivariate regression analysisand ROC curve indicated that FAM72A-D could be used as an independent risk factor affecting the prognosis of HCC patients （P<0.05）. PPI networks showed that FAM72A-D compared with various proteinsparticipated in the progression of HCC. The results of immune infiltration analysis showed that the expression level of FAM72A-D was significantly correlated with the levels of mostinfiltrating immune cells and various biomarkers of immune cells. PD-1, PD-L1, and CTLA-4 levels were positively correlated with FAM72A-D expression. Conclusions FAM72s were highly expressed in HCC tissues and were associated with immune infiltration and poor prognosis. FAM72s may be significant biomarkers of HCC.

Key words: hepatocellular carcinoma, FAM72 gene family, prognosis, immune infiltration, bioinformatics analysis