ABSTRACT
Objective To investigate the modulation for multidrug resistance cell line K562/A02 us- ing a specific siRNA against mdrl,GST?.Methods siRNA were synthesized targeting the coding region se- quences of mdrl(79～99 nt)and GST?(308～327nt)respectively,and cloned to plasmid pSilence2.1-U6.The cloned products pSilenee-mdr1 and pSilence-GST? were transfected into K562/A02 cells.Expression of mdr1 and GST? mRNA were assayed by SYBR Green Ⅰ real-time PCR.The apoptosis of cell line K562/A02 was examined by Flow cytometry,50% inhibition concentration(IC_(50))of doxorubicin on K562/A02 cell was deter- mined by MTT method.Results The siRNA expression vector against mdr1,GST? mRNA was constructed successfully.After transfected with pSilenee-mdr1,the expression of mdr1 mRNA in K562/A02 in was re- duced 71.5 % compared to the mock transfeetion,from(2.8?1.65)?10~8 copy/?g RNA to(3.9?2.37)?10~7 copy/?g RNA(P