Novel Screening Method Identifies PI 3Kα, mTOR , and IGF 1R as Key Kinases Regulating Cardiomyocyte Survival

Background Small molecule kinase inhibitors ( KI s) are a class of agents currently used for treatment of various cancers. Unfortunately, treatment of cancer patients with some of the KI s is associated with cardiotoxicity, and there is an unmet need for methods to predict their cardiotoxicity. Here, we utilized a novel computational method to identify protein kinases crucial for cardiomyocyte viability. Methods and Results One hundred forty KI s were screened for their toxicity in cultured neonatal cardiomyocytes. The kinase targets of KI s were determined based on integrated data from binding assays. The key kinases mediating the toxicity of KI s to cardiomyocytes were identified by using a novel machine learning method for target deconvolution that combines the information from the toxicity screen and from the kinase profiling assays. The top kinases identified by the model were phosphoinositide 3‐kinase catalytic subunit alpha, mammalian target of rapamycin, and insulin‐like growth factor 1 receptor. Knockdown of the individual kinases in cardiomyocytes confirmed their role in regulating cardiomyocyte viability. Conclusions Combining the data from analysis of KI toxicity on cardiomyocytes and KI target profiling provides a novel method to predict cardiomyocyte toxicity of KI s.