In vitro anticancer effects of recombinant anisoplin through activation of SAPK/JNK and downregulation of NFκB

• Published in: Toxicology in vitro 2024-02, Vol.94, p.105737-105737, Article 105737
• Main Authors: Patra, Arupam, Kandasamy, Thirukumaran, Ghosh, Siddhartha Sankar, Saini, Gurvinder Kaur
• Format: Article
• Language: English
• ISSN: 0887-2333; 1879-3177
• DOI: 10.1016/j.tiv.2023.105737

Emerging chemotherapeutic resistance is considered as one of the major obstacles in breast cancer therapy. Fungal ribotoxins possess promising therapeutic potential against cancer owing to their ribosome-targeted protein synthesis inhibitory action. Though the entomopathogenic ribotoxin anisoplin was characterized in the earlier study, its therapeutic efficacy against cancer cells remained unexplored. In the current study, recombinant anisoplin has been successfully produced in Escherichia coli BL21(DE3) expression system and further purified and validated by in silico, biophysical and functional characterizations. Recombinant anisoplin significantly reduced the viability of MCF-7 breast cancer cells in a dose-dependent manner. It exhibited an IC50 value of 4 μM with concurrent 3.5 fold elevation in the intracellular reactive oxygen species. Anisoplin also resulted in depolarization of the mitochondrial membrane and subsequently induced apoptosis, as evident from flow cytometric analyses. In addition, MCF-7 cells significantly lost their self-renewal capability for clonal expansion and regeneration upon treatment. Immunoblotting experiments further confirmed activation of downstream JNK-dependent MAP kinase signaling pathway due to ribotoxic stress response generated by anisoplin through upregulation of phospho-SAPK/JNK expression. This upregulation was further correlated with the NFκB expression profile, leading to cell death, highlighting therapeutic potential of the recombinant anisoplin.