[Experimental study of adenovirus-mediated p53 gene on the reversal of multidrug resistance in breast cancer].
OBJECTIVE
To explore the effects of adenovirus-mediated wild-type p53 gene (Ad-p53) on the reversal of multidrug resistance (MDR) and multidrug resistance gene-1 (MDR1) in adriamycin (ADM) resistant human breast cancer cell.


METHODS
Ad-p53 was transfected into the human breast cancer cells of the line MCF-7/ADM. p53 protein expression was detected by flow cytometry (FCM). The cell proliferation was assessed by trypan blue dye exclusion. The effects of Ad-p53 on ADM mediated drug resistance were observed by MTT assay. The expression levels of MDR1 mRNA were detected with real-time RT-PCR.


RESULTS
The expression rate of p53 protein of the MCF-7/ADM cell was increased from 10.24% to 36.20% after transfected by MOI(50) Ad-p53 for 48 hours. The growth inhibition rate was 7.4 % (P = 0.003). The chemosensitivity of MCF-7/ADM to ADM increased by 11.6 times (P = 0.001). The result of real-time RT-PCR reveales that MDR1 mRNA was decreased from 1.25 +/- 0.01 to 0.91 +/- 0.01 (P = 0.011) after the MCF-7/ADM cells were transfected by Ad-p53.


CONCLUSIONS
Ad-p53 can inhibit the expression of MDR1 gene and partially reverse the MDR of MCF-7/ADM cells, thus enhancing the chemosensitivity of human breast cancer cells to ADM.
He
Shi-zhi
SZ
Cancer Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
Qi
Xiao-dong
XD
Zhang
Xiao-ming
XM
Wang
Yu
Y
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics; D000256:Adenoviridae / Q000235:genetics*; D000970:Antineoplastic Agents / Q000494:pharmacology; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D016158:Genes, p53 / Q000235:genetics*; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D012333:RNA, Messenger; D004317:Doxorubicin