Abstract
BACKGROUND: CANT1, as calcium-activated protein nucleotidase 1, is a kind of phosphatase. It is overexpressed in some tumors and related to poor prognosis, but few studies explore its function and carcinogenic mechanism in hepatocellular carcinoma (HCC). METHODS: The expression of CANT1 mRNA and protein was analyzed by the Cancer Genome Atlas (TCGA) database and immunohistochemistry(IHC) staining. The relationship between CANT1 expression and clinicopathology was evaluated by various public databases. The receiver operating characteristic (ROC) curve was used to assess the diagnostic accuracy of CANT1 by the area under curve (AUC). Univariate, multivariate Cox regression and Kaplan-Meier curves were applied to evaluate the predictive value of CANT1 on the prognosis of HCC. Methsurv was used to analyze gene changes and DNA methylation, and its impact on prognosis. The enrichment analysis of DEGs associated with CANT1 revealed the biological process of CANT1 based on Gene Set Enrichment Analysis (GSEA). The relationship between immune cell infiltration level and CANT1 expression in HCC was investigated using the single-sample GSEA (ssGSEA) method and the Tumor Immune Estimation Resource (TIMER) database. Finally, the association between CANT1 and immune checkpoints and drug sensitivity was also analyzed. RESULTS: CANT1 was highly expressed in 22 cancers, including HCC, and CANT1 overexpression in HCC was confirmed by IHC. The expression of CANT1 was correlated with clinical features, such as histologic grade. Highly expressed CANT1 caused poor overall survival (OS) of HCC patients. Univariate and multivariate regression analysis suggested that CANT1 was an independent prognostic marker. Of the 31 DNA methylation at CpG sites, three CpG sites were associated with the prognosis of HCC. GSEA indicated that CANT1 was mainly involved in the cell cycle, DNA replication, and etc. Moreover, CANT1 expression was correlated with immune cell infiltration and independently associated with the prognosis of HCC patients. Finally, CANT1 expression was correlated with most immune checkpoints and drug sensitivity. CONCLUSION: CANT1 may be a latent oncogene of HCC, and associated with immune cells and immune checkpoints, which may assist in HCC treatment.