The reactivation of PTEN in response to CK2 blockage was the identified mechanism by which the inhibitor TBB (4,5,6,7-tetrabromobenzotriazole) promotes apoptosis in CML (chronic myeloid leukemia) cells from imatinib resistant patients [85]. This evidence concerns the gene PTEN and chronic myelogenous leukemia, BCR-ABL1 positive.