Confocal microscopy and Western blot analysis demonstrate a substantial decrease in PRH protein levels and decreased nuclear localization of PRH in 13 of 13 primary AML (French American British classification M4/M5) and seven of seven blast crisis CML (bcCML) specimens but not in 11 of 11 M1/M2 AML, seven of eight acute lymphoid leukemia (ALL) specimens, or two of two chronic-phase CML [64]. This evidence concerns the gene HHEX and chronic myelogenous leukemia, BCR-ABL1 positive.