MTOR and cardiac hypertrophy: Dysregulation of various signaling pathways including the mitogen-activated protein kinase (MAPK), protein kinase C (PKC), nuclear factor of activated T cells (NFAT), phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB/Akt), mammalian target of rapamycin (mTOR) and insulin-like growth factor (IGF)-1 pathways, may contribute to the progression of cardiac hypertrophy [52,53,64].