BIRC5 knockdown ameliorates hepatocellular carcinoma progression via regulating PPARγ pathway and cuproptosis.

Background: Hepatocellular carcinoma (HCC) with complex molecular carcinogenesis represents a kind of prevalent neoplasm occurring in the liver. The objective of this study is to illustrate the function of baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5) and underlying action mechanisms in HCC progression.

Methods: Comprehensive bioinformatics methods were conducted to screen differentially expressed genes (DEGs), cuproptosis-associated DEGs, and hub genes. The correlation between BIRC5 and immune cell infiltration, prognosis value was evaluated. The specific effects of BIRC5 silencing on HCC cells was validated by functional assays, and the impact on tumorigenicity and cuproptosis was also elucidated in vivo. Additionally, the effects of BIRC5 deficiency on PPAR pathway were determined using Oroxin A in vitro.

Results: A total of 45 cuproptosis-associated DEGs and 9 hub genes were discovered through bioinformatics. Then 6 core genes were confirmed in Hep-3B and SK-Hep-1 cells with 4 genes upregulated and 2 genes downregulated. Therein, BIRC5 was positively correlated with the infiltration of CD8 T cells, macrophages, and highly expressed BIRC5 exhibited poor prognosis of overall survival in HCC. Furthermore, BIRC5 deletion inhibited the PPARγ pathway, thereby restraining the malignant phenotypes of HCC cells and tumorigenesis in vivo. Additionally, silencing of BIRC5 contributed to the initiation of cuproptosis in HCC.

Conclusions: BIRC5 silencing attenuated HCC through blocking PPARγ pathway and regulating cuproptosis, which may offer therapeutic implications against HCC.