Knockdown of FANCI suppresses hepatocellular carcinoma development via the PI3K/Akt/GSK-3β pathway.

Abstract

Background: Abnormal expression of Fanconi anaemia complementation group I (FANCI) has been implicated in carcinogenesis. However, the precise role of FANCI in the development of hepatocellular carcinoma (HCC) remains unclear.

Materials & methods: We conducted a comprehensive bioinformatics analysis of FANCI's role based on HCC patient sequencing data in the TCGA and GEO databases. Then, we performed qPCR, Western blotting (WB), and immunohistochemistry (IHC) assays. SiRNA-mediated knockdown of FANCI was conducted, followed by CCK-8, EdU staining, and colony formation experiments to evaluate the impact of FANCI knockdown on HCC cell behaviour. Flow cytometry was employed to explore alterations in the cell cycle after FANCI knockdown in HCC cell lines. Furthermore, RNA sequencing was performed to investigate potential mechanisms following FANCI knockdown, and WB analysis was used to validate the corresponding pathway.

Results: Our bioinformatics analysis revealed elevated expression of FANCI in HCC, which was subsequently validated through qPCR, WB, and IHC assays. High expression of FANCI was significantly associated with a poor prognosis in HCC patients. Univariate and multivariate Cox regression analyses identified FANCI as an independent prognostic risk factor for HCC patients. Additionally, the coexpressed genes of FANCI were found to be associated with multiple cancer pathways. Knockdown of FANCI expression significantly inhibited HCC cell proliferation and colony formation by inducing cell cycle arrest. Further WB analysis revealed that FANCI knockdown suppressed the expression of Cyclin D1 and p-AKT while increasing the expression of GSK-3β in HCC cells. However, no significant differences were observed in the expression levels of AKT and PI3K.

Conclusion: Overall, our research provides substantial proof of FANCI's crucial function as an oncogene in HCC. It could serve as a potential prognostic marker, therapeutic target, and tumorigenic factor in HCC.