Targeting z-Crystallin by aspirin restores the sensitivity to cisplatin in resistant A2780 ovarian cancer cells

Abstract

Abstract Purpose Ovarian cancer is the deadliest gynaecologic malignancies worldwide. Platinum based chemotherapy is the mainstay treatment for ovarian cancer; however, frequent recurrence and chemoresistance onset in patients with advanced diseases remain a therapeutic challenge. Although mechanisms underlying the development of chemoresistance are still ambiguous, the B-cell lymphoma-2 (Bcl-2) family is closely associated with chemoresistance in ovarian cancer. We previously disclosed that Zeta-Crystallin (CryZ) is a post-transcriptional regulator of Bcl-2 gene expression, by binding to bcl-2 mRNA and increasing its half-life. Here, we investigated the role of CryZ as a novel therapeutic target in ovarian carcinoma by modulating the protein activity with acetylsalicylic acid (ASA) to restore chemosensitivity.Methods Inhibition of CryZ binding activity to Bcl-2 and Bcl-xl mRNA targets by ASA was evaluated in A375 cells. Cytotoxicity assays were conducted in A2780S and A2780R ovarian cancer cells to evaluate if CryZ binding activity inhibition and CryZ silencing were able to reverse cisplatin resistance.Results ASA inhibits the binding of CryZ to Bcl-2 and Bcl-xl mRNAs. Furthermore, ASA-treatment or CryZ silencing are able to increase and restore the chemosensitivity in both sensitive and resistant A2780 ovarian cancer cell lines, respectively. ​Conclusion In this research article we demonstrated that the pharmacological or genetic inhibition of CryZ restores the sensitivity to cisplatin in a model of sensitive or resistant ovarian cancer cells. These findings suggest a new gene-targeted chemotherapeutic approach to restore the cytotoxicity in drug-resistant ovarian cancers and increase the sensitivity in non-resistant cells.