Dipanjan Ghosh

Girdin silencing enhances mebendazole-mediated anticancer activity: a combinatorial therapeutic strategy for ovarian cancer

Ovarian cancer is among the deadliest gynecological malignancies due to its aggressive nature and limited treatment options. Mebendazole (MBZ), a known antiparasitic drug, has shown anticancer activity in several cancer types, though its mechanisms, particularly in ovarian cancer, remain unclear. Girdin (CCDC88A), a key regulator of Akt signaling and cancer cell invasion, represents a promising therapeutic target. This study explores the combined effect of MBZ and Girdin knockdown in ovarian cancer cell lines OVCAR3 and OAW42. Cells were treated with MBZ and transfected with Girdin-targeting siRNA, either individually or in combination. Biochemical assays (migration, invasion, and clonogenicity) and immunoblotting were used to assess the molecular mechanism and protein expression. Computational techniques, including homology modeling, molecular docking, structural interaction fingerprinting (SIFt), and density functional theory (DFT), were employed to study MBZ-Girdin binding. In addition, protein-protein interaction (PPI) network analysis and KEGG pathway enrichment (visualized using Cytoscape) were conducted to understand broader molecular effects. Our results showed that both MBZ and Girdin knockdown significantly decreased Girdin levels, with the combination yielding a greater inhibitory effect. This dual approach led to marked suppression of ovarian cancer cell migration, invasion, and colony formation. Docking studies confirmed stable MBZ binding to Girdin's catalytic domain, supported by favorable binding energies and molecular interactions. This is the first study to demonstrate that MBZ's anticancer efficacy is significantly enhanced by Girdin silencing, implicating the modulation of critical oncogenic pathways.

Mebendazole Exerts Anticancer Activity in Ovarian Cancer Cell Lines via Novel Girdin-Mediated AKT/IKKα/β/NF-κB Signaling Axis

Mebendazole (MBZ), a benzimidazole anthelmintic and cytoskeleton-disrupting compound, exhibits antitumor properties; however, its action on ovarian cancer (OC) is not clearly understood. This study evaluates the effect of MBZ on OC cell lines OVCAR3 and OAW42, focusing on cell proliferation, migration, invasion, and cancer stemness. The underlying mechanisms, including cytoskeletal disruption, epithelial–mesenchymal transition (EMT), and signaling pathways, were explored. MBZ inhibited OVCAR3 and OAW42 cell proliferation in a dose- and time-dependent manner. Additionally, MBZ significantly impedes migration, spheroid invasion, colony formation, and stemness. In addition, it reduced actin polymerization and down-regulated CSC markers (e.g., CD24, CD44, EpCAM). Moreover, MBZ suppressed MMP-9 activity and inhibited the EMT marker as judged by decreased N-Cadherin and Vimentin and increased E-Cadherin. Furthermore, MBZ induced G2/M cell cycle arrest by modulating Cyclin B1, CDC25C, and WEE1. Also, it triggered apoptosis by disrupting mitochondrial membrane potential. Mechanistic studies revealed a significant downregulation of Girdin, an Akt modulator, along with reduced p-Akt, p-IKKα/β, and p-NF-κB, indicating MBZ’s novel mechanism of action through the Girdin-mediated Akt/IKKα/β/NF-κB signaling axis. Thus, by targeting Girdin, MBZ presents a promising repurposed therapeutic strategy to inhibit cancer cell proliferation and metastasis in ovarian cancer.