TNNI3 and heart failure: In agreement with other reports [35, 40–43] we detected elevation in cTn I level after doxorubicin administration that could be linked with cardiomyocytes death [44] might as a result of a massive rise in reactive oxygen species and their effects on cardiomyocytes leading to cellular necrosis, evidenced histopathologically in the heart section of Doxorubicin group, and cardiac insufficiency.