Abstract
BACKGROUND: Non-small cell lung cancer (NSCLC) is frequently characterized by poor response to cisplatin (DDP)-based chemotherapy, with increasing evidence suggesting that inflammatory cytokines in the tumor microenvironment contribute to chemoresistance. AIM: To investigate the role of inflammatory cytokines in DDP resistance and to effect of IL-6 inhibition on chemosensitivity in NSCLC. METHODS: Twenty NSCLC patients were grouped into DDP-sensitive or DDP-resistant cohorts based on their clinical response. Cytokine levels in tumor tissues and NSCLC cell lines, including DDP-resistant A549/DDP and SK-MES-1/DDP, were quantified using enzyme-linked immunosorbent assay. To verify the effects of interleukin (IL)-6 on DDP resistance, NSCLC and resistant cells were treated with IL-6 inhibitors tocilizumab (TCZ), followed by DDP treatment. Cell viability, apoptosis, migration and invasion were detected via cell counting kit-8, flow cytometry, scratch assay, and transwell, respectively. RESULTS: IL-6, IL-8, and tumor necrosis factor-α levels were significantly elevated in DDP-resistance tissues and cell models compared to sensitive controls (P < 0.05). TCZ treatment significantly reduced the half-maximal inhibitory concentration of DDP in resistant cells, induced apoptosis, and hindered migration and invasion (P < 0.05). IL-6 and IL-8 were identified as key cytokines associated with DDP resistance. CONCLUSION: These findings demonstrated that IL-6 and related cytokines contribute to DDP resistance in NSCLC. IL-6 inhibition restores chemosensitivity and may serve as a promising therapeutic strategy in resistant NSCLC.