CBS and chronic myelogenous leukemia, BCR-ABL1 positive: However, Wang and colleagues argue that the increased production of sulfides as by-products of CBS activity is tumorigenic; thus the inhibition of CBS activity in K562 and mononuclear cells isolated from the bone marrows of CML patients using the CBS-inhibitor aminooxy acetic acid (AOAA) lead to an overall reduction in proliferation and the induction of apoptosis in these cells (21).