Protection of platinum-DNA adduct formation and reversal of cisplatin resistance by anti-MRP2 hammerhead ribozymes in human cancer cells

Int J Cancer. 2005 Jun 20;115(3):393-402. doi: 10.1002/ijc.20899.

Abstract

Resistance to platinum-containing antineoplastic drugs is the major limitation in their clinical use. To elucidate the role of the ABC transporter MRP2 in platinum drug resistance, its expression was analyzed in human cisplatin-resistant cell lines: the ovarian carcinoma line A2780RCIS, the adrenocortical carcinoma line D43/86RCIS and the melanoma line MeWoCIS1. All these cells showed overexpression of MRP2. For reversal of platinum resistance, 2 anti-MRP2 hammerhead ribozymes were introduced into A2780RCIS cells. Both ribozymes showed gene-silencing activities and reversed the drug-resistant phenotype. Moreover, formation of platinum-induced intrastrand cross-links was measured in DNA. The level of DNA platination corresponded inversely to the level of MRP2 expression and was accompanied by increased caspase-3-dependent apoptosis. Kinetics of formation and elimination of platinum-DNA adducts suggest that the DNA repair capacity was not altered; the decrease in platinum-DNA adduct formation was rather a reflection of the protecting activity of MRP2. In conclusion, functional inhibition of MRP2 might be a promising strategy in the reversal of resistance to platinum-based anticancer drugs. This was reflected by the specific inhibition of MRP2 by ribozyme technology, indicating that this gene therapeutic approach may be applicable as a specific means to overcome platinum resistance in human neoplasms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / antagonists & inhibitors
  • ATP Binding Cassette Transporter, Subfamily B / genetics*
  • ATP Binding Cassette Transporter, Subfamily B / metabolism
  • ATP-Binding Cassette Transporters / antagonists & inhibitors
  • ATP-Binding Cassette Transporters / genetics*
  • ATP-Binding Cassette Transporters / metabolism
  • Adrenocortical Carcinoma / genetics
  • Adrenocortical Carcinoma / metabolism
  • Adrenocortical Carcinoma / pathology
  • Antineoplastic Agents / metabolism
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Base Sequence
  • Caspase 3
  • Caspases / metabolism
  • Cisplatin / metabolism
  • Cisplatin / pharmacology*
  • Cross-Linking Reagents
  • DNA Adducts / metabolism*
  • DNA Repair
  • Drug Resistance, Multiple
  • Drug Resistance, Neoplasm*
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Silencing*
  • Humans
  • Kinetics
  • Melanoma / genetics
  • Melanoma / metabolism
  • Melanoma / pathology
  • Molecular Sequence Data
  • Ovarian Neoplasms / genetics
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology
  • Platinum / metabolism
  • Platinum / pharmacology
  • RNA, Catalytic / pharmacology*
  • Skin Neoplasms / genetics
  • Skin Neoplasms / metabolism
  • Skin Neoplasms / pathology
  • Tumor Cells, Cultured / drug effects
  • Tumor Cells, Cultured / pathology

Substances

  • ATP Binding Cassette Transporter, Subfamily B
  • ATP-Binding Cassette Transporters
  • Antineoplastic Agents
  • Cross-Linking Reagents
  • DNA Adducts
  • RNA, Catalytic
  • hammerhead ribozyme
  • Platinum
  • multidrug resistance protein 3
  • CASP3 protein, human
  • Caspase 3
  • Caspases
  • Cisplatin