T-3861174 is an inhibitor of prolyl-tRNA synthetase ( PRS , Aminoacyl-tRNA Synthetase ) without completely inhibiting its translation process. T-3861174 activates the GCN2-ATF4 pathway and induces death in multiple tumor cell lines, including SK-MEL-2. T-3861174 demonstrated significant antitumor activity in multiple xenograft models without significantly affecting body weight.