Development and characterization of two human tumor sublines expressing high-grade resistance to the cyanoguanidine CHS 828.

Abstract

The cyanoguanidine CHS 828 has shown promising antitumor properties and is currently in early clinical trials, although the mechanism of action still is largely unknown. In this study, resistant sublines of the histiocytic lymphoma cell line U-937 GTB and the myeloma line RPMI 8226 were developed by culturing under gradually increasing concentrations of CHS 828 until reaching 25 times the parental line EC50s. The new phenotypes demonstrate more than 400-fold resistance to CHS 828 and cross-resistance to six cyanoguanidine analogs, but no resistance to nine standard drugs of different mechanistic classes or to the cytotoxic guanidines m-iodobenzylguanidine and methylglyoxal-bis(guanylhydrazone). The resistant phenotypes were stable for several months even if cultivated in drug-free medium and no difference in proliferation, ultrastructural or morphologic appearance in the sublines could be detected. Neither was decreased accumulation of tritium-labeled CHS 828 observed. Furthermore, the new U-937 phenotype was not accompanied by changes in differentiation or an altered cell-cycle distribution. In the myeloma cell line, esterase activity was shown to be moderately enhanced. Two-dimensional protein electrophoresis was undertaken to unmask possible resistance-mediating proteins and/or the target molecule(s) for CHS 828. In the myeloma cell line, lambda light chain immunoglobulin (down-regulated) and a fatty acid-binding protein (up-regulated) were identified. The findings presented here indicate that development of specific cellular alterations is responsible for the gained CHS 828 resistance.

• Authors: Joachim Gullbo, Henrik Lövborg, Sumeer Dhar, Agneta Lukinius, Fredrik Oberg, Kenneth Nilsson, Fredrik Björkling, Lise Binderup, Peter Nygren, Rolf Larsson
• Journal: Anti-cancer drugs (Anticancer Drugs) Vol. 15 Issue 1 Pg. 45-54 (Jan 2004) ISSN: 0959-4973 [Print] England
• PMID: 15090743 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Cyanides
• Guanidines
• N-(6-chlorophenoxyhexyl)-N''-cyano-N''-4-pyridylguanidine
• Tritium

Topics

• Antineoplastic Agents (pharmacology, therapeutic use)
• Cell Cycle (drug effects)
• Cell Line, Tumor (cytology, drug effects, ultrastructure)
• Cell Survival (drug effects)
• Cyanides (pharmacology, therapeutic use)
• Drug Resistance, Neoplasm (drug effects, genetics)
• Drug Screening Assays, Antitumor
• Electrophoresis, Gel, Two-Dimensional
• Guanidines (pharmacology, therapeutic use)
• Humans
• Lymphoma, Large B-Cell, Diffuse
• Microscopy, Electron
• Multiple Myeloma
• Phenotype
• Tritium