Expression of the multidrug-resistance-associated protein (MRP) gene in human colorectal, gastric and non-small-cell lung carcinomas.
MRP has been identified as another multidrug-resistance (MDR) gene and may be involved in an alternative MDR mechanism in some solid tumors. We investigated the expression of MRP mRNA in multidrug-resistance KB sublines (KB-8-5, KB-C2, C-A40 and C-A120), human non-small-cell lung carcinomas (NSCLC), gastric and colorectal carcinomas, and compared it with that in drug-sensitive human KB cells. MRP gene expression was elevated in 8 of 9 (89%) squamous-cell carcinomas of the lung. Furthermore, MRP expression in 4 squamous-cell carcinomas (L13, 18, 19 and 20) was more than 3.6 times higher than in KB-3-1 cells, and the average MRP mRNA expression level of all squamous-cell carcinomas was significantly higher than that of adenocarcinoma of the lung and of colorectal and gastric carcinomas. These results suggested that the MRP is responsible, at least in part, for drug resistance in some squamous-cell carcinomas of the lung.
Chuman
Y
Y
Institute for Cancer Research, Faculty of Medicine, Kagoshima University, Japan.
Sumizawa
T
T
Takebayashi
Y
Y
Niwa
K
K
Yamada
K
K
Haraguchi
M
M
Furukawa
T
T
Akiyama
S
S
Aikou
T
T
D018528:ATP-Binding Cassette Transporters / Q000032:analysis / Q000235:genetics*; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D018432:Drug Resistance, Multiple / Q000235:genetics*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger / Q000032:analysis; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D018528:ATP-Binding Cassette Transporters; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger