Synergistic Induction of Dual Transcriptional and Replicative Stress by Etoricoxib and Ciprofloxacin Elicits Potent and Selective Anticancer Activity in Cervical Carcinoma

Objective: This study explored the combined anticancer effects of etoricoxib and ciprofloxacin on HeLa cells, emphasizing their mechanisms involving transcriptional and replicative stress, and assessed their selectivity versus normal cells and cisplatin. Materials and Methods: The cytotoxic potential of etoricoxib, ciprofloxacin, etoricoxib–ciprofloxacin mixture, and cisplatin was evaluated on HeLa cells and normal human foreskin fibroblasts (HFF) utilizing MTT assay. The synergistic interactions were quantified using the Combination Index (CI) and the Dose Reduction Index (DRI). Further mechanistic insights were illustrated by measuring key apoptotic proteins, such as phospho-IκBα and p21, using an enzyme-linked immunosorbent assay (ELISA). Additionally, molecular docking studies targeted IKKβ and topoisomerase IIα to elucidate potential molecular interactions. Results: The mixture showed a significantly enhanced cytotoxic effect against HeLa cells, achieving a much lower IC₅₀ value (37.49 µg/mL at 72 hours) compared to either agent alone or cisplatin. The high selectivity index (>26.67) indicates a preferential targeting mechanism toward cancerous cells. Mechanistic studies revealed that this combination simultaneously inhibits the NF-κB signaling pathway, as evidenced by decreased IκBα phosphorylation, and induces replicative stress by increasing p21 expression. Molecular docking studies further supported these findings, showing favorable binding affinities of etoricoxib to IKKβ and ciprofloxacin to topoisomerase IIα, with docking scores of -6.2 kcal/mol and -7.5 kcal/mol, respectively, thus confirming a dual-targeting therapeutic approach. Conclusion: The combined use of etoricoxib and ciprofloxacin has been shown to synergistically promote apoptosis in cervical cancer cell lines through a dual-stress mechanism. Its significant efficacy and selectivity indicate a promising therapeutic approach that could overcome limitations associated with existing chemotherapy protocols, thereby warranting further investigation in in vivo models and clinical studies.