Testicular cancer, generally very responsive to CDDP, has low level of ERCC1, providing further correlative evidence

for the importance of ERCC1 in CDDP resistance [34]. Given its involvement in the NER DNA repair pathway, we paid special attention to ERCC1. A previous study has proved that the suppression of ERCC1 expression in human cancer cells leads to an increased sensitivity to CDDP, and ERCC1 has been presumed to be an attractive target to confer increased cellular sensitivity to CDDP-based chemotherapy [35]. The results of this study suggest that the expression of ERCC1 CA-4948 chemical structure is significantly down-regulated with the transfection of Fas in H446/CDDP cells, which may contribute to the decreased resistance to CDDP. Increased glutathione (GSH) may cause resistance by binding/inactivating cisplatin, enhancing DNA repair, or reducing cisplatin-induced oxidative stress [36]. Glutathione-S-transferase (GST), particularly GST-π [37, 38], may augment drug resistance by catalyzing GSH-drug binding.

Clinically, GST-π gene amplification [39], immunostaining [40], and plasma levels [41] have been correlated with cisplatin resistance, suggesting that platinum detoxification by GSH and GST may be clinically important. The results of this study suggest that the expression of GST-π is significantly down-regulated with the transfection of Fas in H446/CDDP cells, which may contribute to the decreased resistance to CDDP. Conclusion Selleckchem AZD1390 Our results show that Fas gene transduction can reverse the multidrug resistance (MDR) of human drug resistant SCLC cell H446/CDDP, for which the enhanced cell sensitivity to apoptosis and decreased expression of GST-π and ERCC1 may be responsible. Although the biological function of Fas in SCLC needs to be further investigated, the present results of our study provide a framework for the illumination of the resistance to CDDP GSK-3 inhibitor mediated by Fas, and will aid in the effective use of CDDP in SCLC treatment. Acknowledgements This work was supported by

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