Objective To investigate the upregulation of BceIlspecific Moloney murine leukemia virus integration site1 (BMI1) in hepatocellular carcinoma (HCC) and its relationship with prognosis. Methods Bioinformatics was used to analyze the correlation between BMI1 and clinical data of patients with liver cancer.Realtime quantitative PCR was used to verify the expression of BMI1 in HCC tissues

and the relationship between BMI1 expression level and clinicopathological features was analyzed.The liver cancer gene expression data GSE56140 was downloaded from GEO database to analyze the biological function of BMI1 high expression in HCC. Results The online analysis of linkedomics showed that BMI1 was associated with pathological N stage

race and overall survival of 377 patients with HCC(P<0.05);BMI1 was mainly expressed in the nucleus.The KaplanMeier plotter analysis showed:HR=1.46

95%CI:1~2.13 and log rank P=0.048.The difference between the BMI1 high expression group and the low expression group was statistically significant(P<0.05).At the same time

the high expression group of BMI1 was significantly associated with tumor size

vascular invasion

TNM stage

Edmonson classification

tumorfree capsule

and the difference was statistically significant(P<0.05).KaplanMeier results showed that patients with high expression of BMI1

the prognosis was worse than that of patients with low BMI1 expression.Gene enrichment analysis indicated that BMI1 may promote malignant transformation of liver cancer cells via cell cycle

RNA degradation

splice

DNA replication

oxidative phosphorylation

mismatch repair and other biological processes.Conclusion BMI1 may be involved in the occurrence and development of HCC and is associated with disease prognosis in HCC patients.