Reversal of drug resistance using hammerhead ribozymes against multidrug resistance-associated protein and multidrug resistance 1 gene

• Published in: International journal of oncology Vol. 21; no. 5; p. 1021
• Main Authors: Nagata, Junko, Kijima, Hiroshi, Hatanaka, Hiroyuki, Asai, Satomi, Miyachi, Hayato, Abe, Yoshiyuki, Yamazaki, Hitoshi, Nakamura, Masato, Watanabe, Norihito, Mine, Tetsuya, Kondo, Takahito, Scanlon, Kevin J, Ueyama, Yoshito
• Format: Journal Article
• Language: English
• Published: Greece 01-11-2002
• Subjects: ATP-Binding Cassette, Sub-Family B, Member 1 - antagonists & inhibitors; Colonic Neoplasms - drug therapy; Colonic Neoplasms - genetics; Colonic Neoplasms - pathology; Drug Resistance, Neoplasm; Genes, MDR; Humans; Multidrug Resistance-Associated Proteins - antagonists & inhibitors; Multidrug Resistance-Associated Proteins - genetics; RNA, Catalytic - pharmacology; RNA, Catalytic - therapeutic use; Tumor Cells, Cultured
• ISSN: 1019-6439
• DOI: 10.3892/ijo.21.5.1021

We examined the effects of suppressing multidrug resistance-associated protein (MRP) and multidrug resistance 1 (MDR1) gene expression in HCT-8DDP human colon cancer cell lines, which showed both cisplatin and multidrug resistance. Hammerhead ribozymes, designed to cleave MRP mRNA (anti-MRP Rz) and MDR1 mRNA (anti-MDR1 Rz), were transfected into the HCT-8DDP cells. Drug sensitivity was estimated by MTT assay in vitro. The HCT-8DDP/anti-MRP Rz cells were more sensitive to doxorubicin (DOX) and etoposide (VP-16) by 2.5- and 4.1-fold, respectively, compared with HCT-8DDP cells. The HCT-8DDP/anti-MDR Rz cells were more sensitive to DOX and VP-16 by 2.3- and 3.8-fold, respectively. The anti-MRP Rz and anti-MDR1 Rz significantly down-regulated resistance to DOX and VP-16, while anti-MRP Rz and anti-MDR1 Rz did not affect resistance to cisplatin, methotrexate and 5-fluorouracil. The hammerhead ribozyme-mediated specific suppression of MRP or MDR1 was sufficient to reverse multidrug resistance in the human colon cancer cell line.