Identification of novel cardioprotective molecules for anti-cancer combination therapy

Abstract

Do an improvement in cancer treatments, cancer survivors can develop treatment-related cardiotoxicity. The aim of this project is to identify new compounds able to protect the cardiomyocytes from cell death to avoid cardiotoxicity. A screening of 1.600 compounds (Prestwick and CEA Saclay libraries) was performed to identify potential cardioprotective compounds by methylene-blue cell survival assay. For this, a necrosis model induced by H 2 O 2 and an apoptosis model induced by camptothecin were developped. The screening allowed us to identify 21 molecules able to increase cell survival (> average + 3 standard deviation (SD)). Then, these molecules were validated as cardioprotective using permeability membrane tests: lactate deshydrogenasse (LDH) colorimetric assay and Propidium Iodid fluorescence assay. Mechanisms involved in the cardioprotective effect of the identified molecules are being investigated. Western-blots were performed in order to verify our hypothesis for autophagy activation. We showed that some of the 21 compounds tested increased LC3-II, a protein marker of autophagy. Rapamycin, known as autophagy activator trough inhibition of mTOR was used as positive control. Indeed, it has been shown that under stress condition, autophagy is activated, promoting cell survival by releasing energy substrates via degradation of the cellular components and by eliminating defective or damaged organelles. In addition, we verified that the molecules do not induce cancer cells proliferation during 48h using 3 cancer cell lines, e.g. A549, HepG2 and HeLa, which is crucial in the perspective of drug development. Among the 21 molecules identified, we chose to focus only on 5 more potent molecules to pursue the project. In order to complete the study on autophagy pathway, we plan to perform transcriptomic studies by RNA-seq method.