Integrative functional-genomics analysis identifies CCT3 as a prognostic biomarker in osteosarcoma, involving the beta-catenin/c-MYC axis in malignant progression

Objective Osteosarcoma prognosis remains challenging, and reliable molecular determinants are lacking. We integrated multi-dimensional functional genomic and transcriptomic data to construct a prognostic model and investigated the key candidate gene CCT3 in osteosarcoma malignancy. Methods We intersected CRISPR-Cas9 dependency genes with differentially expressed genes to derive a 64-gene candidate pool, followed by stepwise Cox regression to build a risk model. Model performance was validated in training and external cohorts. Immune microenvironment, drug sensitivity, and experimental validation were performed following CCT3 knockdown. Results An 8-gene risk model was constructed and significantly stratified overall survival. The high-risk group showed lower immune scores, reduced immune-cell infiltration, and downregulation of multiple immune checkpoint genes, indicating an immune-poor phenotype. Among 7 drugs with differential sensitivity, the high-risk group was more sensitive to 6 agents, including AZ6102, while showing resistance to Entospletinib. CCT3 was overexpressed in osteosarcoma tissues and cell lines; its knockdown suppressed proliferation and clonogenicity. Mechanistically, CCT3 depletion attenuated Wnt/beta-catenin signaling and reduced stemness markers CD24 and c-MYC. Conclusion Our integrative approach establishes an effective prognostic model for osteosarcoma and identifies CCT3 as a pro-tumorigenic gene, likely through the beta-catenin/c-MYC axis, representing a promising prognostic biomarker and therapeutic vulnerability.