Abstract
OBJECTIVE: Ring finger protein 145 (RNF145), an E3 ubiquitin ligase, is significantly upregulated in hepatocellular carcinoma (HCC). However, its role in HCC remains unknown. The study aimed to investigate the functions and underlying mechanisms of RNF145 in HCC. METHODS: The role of RNF145 in HCC was investigated using data from The Cancer Genome Atlas (TCGA) and in vitro experimental assays. Its oncogenic functions were assessed using the transwell migration assay and the wound-healing assay. The molecular mechanism was explored through protein immunoprecipitation and western blot analyses. Data from public databases were analyzed to correlate RNF145 expression with clinicopathological features. Univariate and multivariate Cox analyses established RNF145 as an independent prognostic factor. Subsequently, a prognostic nomogram was constructed. RESULTS: RNF145 was upregulated in HCC. The expression level of RNF145 in HCC showed significant correlations with histological grade, pathological stage, and vascular invasion. Functionally, knockdown of RNF145 effectively abolished the migratory and invasive capacities of HCC cells. This pro-metastatic effect is mediated through the RNF145-driven ubiquitination and subsequent degradation of protocadherin 9 (PCDH9). CONCLUSION: Our findings confirm the significant upregulation of RNF145 in HCC and promote metastasis by facilitating PCDH9 ubiquitination and degradation, highlighting its role as a prognostic biomarker and a potential therapeutic target.