Expressions of P?glycoprotein(P?gp) and mdr1 mRNA were downregulated in differentiated cells,meanwhile,a significant decrease of DNR IC??50? in the AML cells with down?expression mdr1 gene was revealed and their sensitivity to anti?cancer drugs increased.

• 结果：分化后的细胞mdr1/P?gp表达水平较分化前明显下降，并且随mdr1/P?gp下降，细胞对柔红霉素敏感性明显增加。