Hyperthermia-induced nuclear translocation of transcription factor YB-1 leads to enhanced expression of multidrug resistance-related ABC transporters

Item Type:	Article
Title:	Hyperthermia-induced nuclear translocation of transcription factor YB-1 leads to enhanced expression of multidrug resistance-related ABC transporters
Creators Name:	Stein, U. and Juerchott, K. and Walther, W. and Bergmann, S. and Schlag, P.M. and Royer, H.D.
Abstract:	Genotoxic stress leads to nuclear translocation of the Y-box transcription factor YB-1 and enhanced expression of the multidrug resistance gene MDR1. Because hyperthermia is used for the treatment of colon cancer in combination with chemoradiotherapy, we investigated the influence of hyperthermia on YB-1 activity and the expression of multidrug resistance-related genes. Here we report that hyperthermia causes YB-1 translocation from the cytoplasm into the nucleus of human colon carcinoma cells HCT15 and HCT116. Nuclear translocation of YB-1 was associated with increased MDR1 and MRP1 gene activity, which is reflected in strong efflux pump activity. However, a combination of hyperthermia and drug treatment effectively reduced cell survival of the HCT15 and HCT116 cells. These results demonstrate that activation of MDR1 and MRP1 gene expression and increased efflux pump activity after hyperthermia were insufficient to cause an increase in drug resistance in colon cancer cell lines. The ability of hyperthermia to abrogate drug resistance in the presence of an increase in functional MDR proteins may provide an explanation for the efficacious results seen in the clinic in colon cancer patients treated with a combination of hyperthermia and chemotherapy.
Keywords:	Antineoplastic Agents, ATP-Binding Cassette Transporters, CCAAT-Enhancer-Binding Proteins, Cell Nucleus, Cell Nucleus Active Transport, Cell Survival, Chloramphenicol O-Acetyltransferase, Colonic Neoplasms, Complementary DNA, Confocal Microscopy, Cultured Tumor Cells, Cytoplasm, DNA-Binding Proteins, Doxorubicin, Fever, Flow Cytometry, Fluorescence Microscopy, Indirect Fluorescent Antibody Technique, Multidrug Resistance-Associated Proteins, NFI Transcription Factors, P-Glycoprotein, Plasmids, Reporter Genes, Reverse Transcriptase Polymerase Chain Reaction, Rhodamines, RNA, Temperature, Time Factors, Transcription Factors, Transfection, Y-Box-Binding Protein 1
Source:	Journal of Biological Chemistry
ISSN:	0021-9258
Publisher:	American Society for Biochemistry and Molecular Biology
Volume:	276
Number:	30
Page Range:	28562-28569
Date:	1 January 2001
PubMed:	View item in PubMed

Repository Staff Only: item control page