Co-ordinated over-expression of the MRP and gamma-glutamylcysteine synthetase genes, but not MDR1, correlates with doxorubicin resistance in human malignant mesothelioma cell lines.
While human malignant mesothelioma is extremely resistant to chemotherapy, its intrinsic resistance mechanisms remain largely unknown. In this study, we used normal human mesothelial cells and 5 human mesothelioma cell lines not previously exposed to chemotherapeutic agents to demonstrate that the mRNA for the multidrug resistance-associated protein (MRP) and gamma-glutamylcysteine synthetase (gamma-GCSh) heavy subunit genes, but not the P-glycoprotein (MDR1) gene, are co-ordinately over-expressed in mesothelioma cell lines. Expression of MRP as detected with an anti-MRP antibody correlated with decreased doxorubicin accumulation and resistance of mesothelioma cells to this drug. Our results strongly suggest roles for MRP and gamma-GCSh in chemoresistance in mesotheliomas.
Ogretmen
B
B
Department of Experimental Oncology, Medical University of South Carolina, Charleston 29425, USA.
Bahadori
H R
HR
McCauley
M D
MD
Boylan
A
A
Green
M R
MR
Safa
A R
AR
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D004317:Doxorubicin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D004848:Epithelium / Q000378:metabolism; D015870:Gene Expression; D005721:Glutamate-Cysteine Ligase / Q000235:genetics*; D006801:Humans; D008654:Mesothelioma / Q000188:drug therapy / Q000201:enzymology / Q000378:metabolism*; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D014407:Tumor Cells, Cultured
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018528:ATP-Binding Cassette Transporters; D004317:Doxorubicin; D005721:Glutamate-Cysteine Ligase; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm