ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The fusion oncoprotein BCR-ABL is a key driver of continuous cell proliferation in CML, activating downstream signaling pathways such as PI3K/AKT signal transducer and MAPK.293,294 Despite BCR-ABL inhibitors transforming life-threatening CML into a manageable chronic condition, issues like resistance and lifelong medication persist.