Abstract
BACKGROUND: Background. Pancreatic adenocarcinoma (PAAD) is a malignancy with a very poor prognosis. The clinical significance of cuproptosis in PAAD combining single cell data with The Cancer Genome Atlas (TCGA) data is unclear. MATERIALS AND METHODS: In this study, we first identified gene modules associated with cuproptosis by performing single-cell analysis and weighted co-expression network analysis (WCGNA). According to TCGA data, Cox regression and LASSO regression analysis were used to establish prognostic models, and PAAD patients were divided into high-risk and low-risk groups according to cuproptosis-related risk score. Then 7 algorithms were used to evaluate cancer immune microenvironment, followed by the mutation analysis. The expression levels and prognostic significance of the 8 model genes were analysed using single-gene analysis, Kaplan-Meier survival plots, and quantitative PCR (qPCR) validation. Finally, the biological function of CEP55 in PAAD was verified by in vitro experiments. RESULTS: We identified cuproptosis-related genes (CRG) in PAAD by performing single-cell analysis and WCGNA, and constructed a cuproptosis-related prognostic model of PAAD by comprehensive bioinformatics analyses. Based on cuproptosis-related risk score, there were significant differences in survival time between two groups. We further constructed a cuproptosis-related risk score-based nomogram to accurately assess PAAD patient prognosis. Immune infiltration analysis revealed that PAAD samples with higher cuproptosis-related scores exhibited significantly lower immune infiltration levels, which may mechanistically underlie their poorer clinical outcomes. Furthermore, the high-risk group had a higher mutation rate of the same mutated gene, which means that they are more likely to benefit from immunotherapy. Finally, we identified that CEP55 was significantly overexpressed in PAAD and correlated with poor patient prognosis. In vitro knockdown of CEP55 effectively suppressed proliferation and invasion capabilities in pancreatic cancer cell lines. CONCLUSIONS: In this study, a novel prognostic model of PAAD was constructed to evaluate the prognosis and immune microenvironment of PAAD patients, and CEP55 was identified as a central gene of PAAD. In vitro studies verified the biological function of CEP55, providing a new potential target for the treatment of PAAD.