2-(1-Hydroxethyl)-4,8-dihydrobenzo[1,2-b:5,4-b′]dithiophene-4,8-dione (BTP-11) enhances the ATRA-induced differentiation in human leukemia HL-60 cells

2-(1-Hydroxethyl)-4,8-dihydrobenzo[1,2-b:5,4-b′]dithiophene-4,8-dione (BTP-11) is a potent enhancer for all-trans retinoic acid (ATRA)-induced differentiation in HL-60 cells. Combination of BTP-11 and ATRA cut down the concentration of ATRA significantly, and that BTP-11 promoted the progression of ATRA-induced into the terminal granulocytic differentiation. Further, Western blot analysis revealed that combination of BTP-11 and ATRA decreased cyclin D/CDK4 and increased C/EBPɛ protein expression to arrest the cells into G0/G1 phase leading to granulocytic maturation. These results confirmed that BTP-11 is a potent enhancer for ATRA-induced differentiation of HL-60 cells, and the great developmental potential of BTP-11 will be expected.