Effects of anticancer agents and scavengers on CMV-promoter-driven exogenous gene expression in genetically modified cells

Abstract

Objectives: This study aimed to investigate whether the levels of rsGFP mRNA and the fluorescence levels of cytomegalovirus (CMV)-promoter-driven rsGFP (red-shifted green fluorescent protein) could be changed by using anticancer agents and also to examine the effects of co-treatment with anticancer agents and scavengers. Methods: The pQBI25 vector, which encodes the CMV promoter and the cDNA for rsGFP, was transfected into FR cells (rat skin fibroblast cell line). FR-pQBI25 cells were then exposed to doxorubicin, 5-fluorouracil, methotrexate or paraquat with or without scavengers such as N-acetyl cysteine (NAC) and edaravone for 48 h. Key findings: The levels of rsGFP mRNA were found to be significantly higher following doxorubicin, 5-fluorouracil and paraquat treatment but were not changed by methotrexate. These levels of rsGFP mRNA were found to be significantly lower after paraquat/edaravone co-treatment compared with paraquat alone. The fluorescence levels of rsGFP were found to be significantly higher following doxorubicin and paraquat treatment but were not changed by 5-fluorouracil and methotrexate. The levels were also found to be significantly lower after paraquat/edaravone co-treatment compared with paraquat alone and also after doxorubicin/NAC co-treatment compared with doxorubicin alone. Conclusions: These findings suggest that CMV-promoter-driven exogenous gene expression may be partly regulated by reactive oxygen species. © 2009 The Authors.