Mechanism of differential sensitivity to cisplatin in nasopharyngeal carcinoma cells.

Cisplatin is used in the treatment of many tumours, including nasopharyngeal carcinoma (NPC). In this study, we studied two nasopharyngeal cancer cell lines with a four-fold difference in sensitivity to cisplatin. Following exposure to cisplatin, the sensitive SUNE1 cell line underwent apoptosis while the relatively resistant CNE1 line died through mitotic cell death. No differences were seen in telomere length or in the cell cycle distribution after cisplatin treatment. However, there was an increase in Bax levels in the sensitive cell line SUNE1, while in the resistant line CNE1 that did not undergo apoptosis, Bax levels fell. Our results suggest that upregulation of Bax is associated with the sensitivity of these NPC cells to cisplatin.