MARS1 and cancer: Of the various ARSs, leucyl-tRNA synthetase (LRS), threonyl-tRNA synthetase, methionyl-tRNA synthetase (MARS), and glutamyl-prolyl-tRNA synthetase interact with proteins in the mTORC1, GCN2, CDK4, and VEGFR signaling pathways that play critical roles in cancer growth [6].