HDAC9 and acute myeloid leukemia: Moreover, multidrug resistance of HDAC inhibitors is associated with BCRP, MPR7, and MRP8. 49, 50, 51The mRNA levels of ABC transporter genes MDR1, BCRP, MRP7, and MRP8 were dramatically increased after exposure to either VPA (3 mM) or TSA (165 nM) for 24 h in AML cell lines and relapsed AML patient samples (#1, #2, and #28).