Figure 6. Analysis of DBT overexpression in sunitinib-resistant RCC cell Lines. (A) Cell Viability Assessment: Comparative analysis of cell viability in sunitinib-resistant RCC cell lines, 786(R)-O and A498(R) following transfection with OE-DBT and control plasmid (pCDNA3.1). (B) Wound Healing and Tumor Sphere Formation Assays: Post-24-hour scraping, this figure illustrates the reduced migration rate in DBT-overexpressing cells compared to control RCC cells. Additionally, a decrease in tumor sphere formation diameter is highlighted. (C) RT-qPCR Analysis: Validation of transfection efficiency and assessment of gene expression changes related to copper apoptosis and cell function in DBT-overexpressed RCC cell lines. (D) Western Blot Analysis: Confirmation of successful transfection and evaluation of protein expression alterations corresponding to cellular functions in DBT-overexpressed cells. (E) Intracellular Copper Ion Levels: Depiction of copper ion concentrations within the cells, emphasizing the effect of DBT overexpression. (F) GSH/GSSG Ratio Assay. (G, H) Combination Treatment Efficacy: Demonstrating the impact of combination treatments on re-sensitizing drug-resistant cells. This includes reductions in both tumor sphere formation diameter and cell viability in DBT-overexpressed RCC cell lines. (*p < 0.05, **p < 0.01).