Integration of Single-cell Sequencing Analysis Reveals Disulfidptosis Related Molecular Subtype and Novel Prognosis System for Osteosarcoma.

BACKGROUND

Osteosarcoma (OS) is one of the most common primary malignancies in children and adolescents. Disulfidptosis, a newly identified form of metabolically induced programmed cell death triggered by disulfide stress, has not yet been explored in OS.

METHODS

We integrated data from public databases and applied a series of bioinformatics approaches, including clustering analysis to classify OS subtypes, and Cox and LASSO regression analysis to identify prognostic disulfidptosis-related genes (DRGs). Enrichment analysis was performed to explore the biological pathways associated with DRG-related molecular subtypes. The immune infiltration landscape was assessed to understand the tumor microenvironment in different risk subgroups. Additionally, drug sensitivity analysis was conducted to evaluate the potential clinical therapeutic strategies of the identified DRG score subgroups. The distribution of DRG expression across OS cell subtypes was further analyzed using single-cell RNA sequencing. In vitro assays, including Western blotting, qRT-PCR, and cell migration and invasion assays, were conducted to validate POLR1D expression and function in OS cells.

RESULTS

We established a DRG-based prognostic model that effectively stratifies OS patients into distinct risk groups with different survival outcomes. The model also revealed significant differences in immune cell infiltration between high and low DRG scores group, suggesting a link between disulfidptosis and the OS immune microenvironment. Drug sensitivity analysis indicated that the DRG signature could guide personalized therapeutic strategies. Single-cell RNA sequencing revealed heterogeneous expression of DRG signature across OS cell subtypes. Functional assays confirmed that POLR1D was aberrantly overexpressed in OS cells and promotes their migration and invasion, supporting its role as a potential oncogenic driver in OS.

CONCLUSION

Our study is the first to investigate the role of DRGs for risk stratification in OS, providing new insights and targets into OS pathogenesis.