BCAT1 and chronic myelogenous leukemia, BCR-ABL1 positive: Following the observation that mice with BP CML display higher levels of proline and BCAAs, Hattori et al. found a significant upregulation of branched chain amino acid aminotransferase 1 (BCAT1) at the mRNA and protein levels in BP-CML as compared to CP-CML or healthy mice [126].