Reversal of multidrug resistance property of carcinoma cells by down-regulating transcription of mdr-1.
- Author:
Peng GAO
1
;
Geng-yin ZHOU
;
Gang YIN
;
Zhi-fu WANG
;
Wen-jun LIU
;
Xiao-yan LIN
Author Information
- Publication Type:Journal Article
- MeSH: ATP-Binding Cassette, Sub-Family B, Member 1; genetics; Breast Neoplasms; genetics; metabolism; pathology; Cell Line, Tumor; Down-Regulation; Drug Resistance, Multiple; genetics; Drug Resistance, Neoplasm; genetics; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Oligonucleotides, Antisense; genetics; metabolism; RNA, Messenger; genetics; metabolism; Reverse Transcriptase Polymerase Chain Reaction; Transcription, Genetic; genetics
- From: Chinese Journal of Pathology 2003;32(6):563-566
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo reverse the multidrug resistance (MDR) property of carcinoma cells by blocking transcription of activating sites of mdr-1.
METHODSBreast carcinoma cells were transinfected with several antisense oligonucleotide (ASODN) complementary to mdr-1 by lipofectin. RT-PCR was used to detect the production of mdr-1mRNA. The expression of P-glycoprotein (gp) was then detected by immunohistochemistry and the function of P-gp was detected by rhodamine123 retention.
RESULTSForty-eight hours after transfection, mdr-1 index of cells treated by ASODN complementary to MA zone (major initiation start zone), MI (minor initiation start zone), C zone (CAAT box), G zone (GC box) of mdr-1 gene was 1.4, 1.9, 1.6 and 2.1 respectively. The rate of P-gp protein expression in treated cells was 14%, 43%, 26% and 39% respectively. The intracellular Rh123 retention in treated cells was 125%, 83%, 102% and 77% respectively. There was significant difference between cells treated by ASODN complementary to MA zone and C zone and drug-resistant cells.
CONCLUSIONSThe ASODN complementary to MA zone and C zone of mdr-1 gene can reverse MDR of drug-resistant cells to various extent, amongst which the former is more effective. Down-regulating transcription of mdr-1 by blocking transcription activating sites can reduce the expression of mdr-1mRNA and P-gp, and thus reversing MDR of carcinoma cells. The ASODN complementary to MI zone, G zone of mdr-1 however do not significantly reverse the MDR property.
