Synergistic antiproliferative effects of the cisplatin and nimotuzumab combination through modulation of EGFR/MEK/ERK signaling in neuroblastoma

This study investigated the synergistic cytotoxic effect of cisplatin and nimotuzumab combination in neuroblastoma cells and their impact on EGFR/MEK/ERK signaling. Human neuroblastoma cells (SH-SY5Y) were treated with cisplatin (1, 3, and 10 µM), nimotuzumab (10 µM), and their combinations (1 µM Cis + 10 µM NMTZ, 3 µM Cis + 10 µM NMTZ, and 10 µM Cis + 10 µM NMTZ) for 48 h. Cell viability was assessed using a proliferation assay, while western blot analysis measured protein expression levels. Quantitative RT-PCR was performed to determine EGFR mRNA expression. Cisplatin monotherapy reduced cell viability with survival rates of 82% (1 µM), 71% (3 µM), and 60% (10 µM) (p<0.05). The combination therapy resulted in enhanced cytotoxicity, with viability decreasing to 54% (1 µM Cis + 10 µM NMTZ), 44% (3 µM Cis + 10 µM NMTZ), and 25% (10 µM Cis + 10 µM NMTZ) (p<0.05, compared to control and single-agent treatments). Western blot data showed a significant decrease in EGFR expression in the combination groups (p<0.05), whereas p-EGFR levels were increased. ERK1/2 expression increased in cisplatin-treated groups but decreased with combination treatment (p<0.01). p-ERK1/2 levels increased in the nimotuzumab-treated groups, suggesting a compensatory activation of survival pathways. Nimotuzumab enhanced cisplatin-induced cytotoxicity in neuroblastoma cells by modulating EGFR/MEK/ERK signaling. Combination therapy reduced cell viability, downregulated EGFR expression, and disrupted ERK1/2-mediated survival mechanisms. Nimotuzumab may mitigate cisplatin resistance by preventing EGFR upregulation, offering a potential strategy to improve neuroblastoma treatment outcomes.