Expression of heat-shock proteins (HSPs) in acute myeloid leukemia (AML)

4431 Resistance to chemotherapy-induced apoptosis and a multidrug-resistance phenotype is the major problem in the treatment of AML. HSPs are responsible for chaperoning a vast array of client proteins that are involved in cell signalling, proliferation and survival. To identify prognostic factors alternative or additional to drug-resistance and apoptosis proteins, we studied the impact of the expression of HSPs (HSP27, HSP60, HSP70, HSP90, and HSP110) in newly diagnosed AML. 98 AML patients were studied before induction chemotherapy. HSP27 was expressed in 38 cases (39%), HSP60 in 25 cases (26%), HSP70 in 57 cases (58%), HSP90 in 40 cases (41%), and HSP110 in 29 cases (30%). There were significant correlations between the expression of the 5 HSPs, mostly between HSP90 and HSP110 (r=0.73). HSP expressions were correlated with that of differentiation antigens (CD34, CD14, CD15, CD33). A correlation was found between the expression of all HSPs and that of MRP (p