This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Meurette, O. Articles by Dimanche-Boitrel, M.-T. Search for Related Content PubMed PubMed Citation Articles by Meurette, O. Articles by Dimanche-Boitrel, M.-T.

Role of Intracellular Glutathione in Cell Sensitivity to the Apoptosis Induced by Tumor Necrosis Factor –Related Apoptosis-Inducing Ligand/Anticancer Drug Combinations

Authors' Affiliation: Institut National de la Santé et de la Recherche Médicale U620, Détoxication et Réparation Tissulaire, Faculté de Pharmacie, Université Rennes 1, Rennes, France

Requests for reprints: Marie-Thérèse Dimanche-Boitrel, Institut National de la Santé et de la Recherche Médicale U620, 2 Av du Pr Léon Bernard, 35043 Rennes Cedex, France. Phone: 33-2-2323-4837; Fax: 33-2-2323-4794; E-mail: marie-therese.boitrel{at}rennes.inserm.fr.

Purpose: We have recently shown that combination of tumor necrosis factor –related apoptosis-inducing ligand (TRAIL) with anticancer drugs induced an apoptotic cell death pathway involving both caspases and mitochondria. The present work further explores the role of intracellular reduced glutathione (GSH) level in cell sensitivity to this cell death pathway.

Experimental Design: Intracellular GSH level was measured by high-performance liquid chromatography. Cell death was detected by immunofluorescence after Hoechst 33342/propidium iodide staining. Reactive oxygen species production was evaluated by flow cytometry after dihydroethidium probe labeling. Western blot analysis was done to study stress-activated protein kinase/c-jun NH₂-terminal kinase (SAPK/JNK) phosphorylation. The Student's t test was used to determine significance of the results. Three to six experiments were done.

Results: GSH depletion enhanced apoptosis induced by TRAIL/cisplatin (CDDP) or TRAIL/5-fluorouracil (5-FU) combinations in both human HT29 colon carcinoma and HepG2 hepatocarcinoma cells, whereas it enhanced cytotoxicity induced only by TRAIL/CDDP in human primary hepatocytes. Our results further suggested that GSH depletion enhanced SAPK/JNK phosphorylation upon TRAIL/5-FU exposure and likely reduced the detoxification mechanisms of CDDP in HT29 cells. Resistance of Bcl-2–expressing HT29 and HepG2 cells to combined treatment was not overcome by GSH depletion, thus indicating that Bcl-2–mediated antiapoptotic effect occurs independently of intracellular GSH level.

Conclusion: GSH depletion could be useful to increase the therapeutic efficacy of cancer treatment by TRAIL/anticancer drug combinations. Furthermore, TRAIL/5-FU combination might be a potential anticancer treatment of human tumors, being ineffective on human primary hepatocytes and thus could be of interest in clinical cancer treatment. Nevertheless, Bcl-2 expression remains an important resistance factor.

Key Words: tumor cells • GSH • Bcl-2 • TRAIL/5-FU • hepatocytes

This article has been cited by other articles:

				H.-Y. Zhang, H.-Q. Wang, H.-M. Liu, Y. Guan, and Z.-X. Du Regulation of tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis by DJ-1 in thyroid cancer cells Endocr. Relat. Cancer, June 1, 2008; 15(2): 535 - 544. [Abstract] [Full Text] [PDF]

				A. Lemarie, E. Bourdonnay, C. Morzadec, O. Fardel, and L. Vernhet Inorganic Arsenic Activates Reduced NADPH Oxidase in Human Primary Macrophages through a Rho Kinase/p38 Kinase Pathway J. Immunol., May 1, 2008; 180(9): 6010 - 6017. [Abstract] [Full Text] [PDF]

				A. Yoshida, H. Takemura, H. Inoue, T. Miyashita, and T. Ueda Inhibition of Glutathione Synthesis Overcomes Bcl-2-Mediated Topoisomerase Inhibitor Resistance and Induces Nonapoptotic Cell Death via Mitochondrial-Independent Pathway Cancer Res., June 1, 2006; 66(11): 5772 - 5780. [Abstract] [Full Text] [PDF]