IP3 receptor antagonist, 2-APB, attenuates cisplatin induced Ca2+-influx in HeLa-S3 cells and prevents activation of calpain and induction of apoptosis
Article first published online: 29 JAN 2009
2007 British Pharmacological Society
British Journal of Pharmacology
Volume 151, Issue 8, pages 1176–1186, August 2007
How to Cite
Splettstoesser, F., Florea, A.-M. and Büsselberg, D. (2007), IP3 receptor antagonist, 2-APB, attenuates cisplatin induced Ca2+-influx in HeLa-S3 cells and prevents activation of calpain and induction of apoptosis. British Journal of Pharmacology, 151: 1176–1186. doi: 10.1038/sj.bjp.0707335
- Issue published online: 29 JAN 2009
- Article first published online: 29 JAN 2009
- (Received January 11, 2007, Revised April 18, 2007, Accepted May 9, 2007)
- anticancer drugs;
- calcium signalling;
- calcium stores;
Background and purpose:
Cisplatin drives specific types of tumour cells to apoptosis. In this study we investigate the involvement of intracellular calcium ([Ca2+]i) in triggering apoptosis in two different cell lines. As cisplatin is used for the treatment of several forms of cancer we choose HeLa-S3 and U2-OS as two examples of tumour cell lines.
Cisplatin (1nM–10μM) was applied to HeLa-S3 and U2-OS cells and [Ca2+]i measured with fluo-4, using laser scanning microscopy. Inositol-1,4,5-trisphosphate (IP3) receptors were visualized with immunostaining. Membrane conductances were measured with patch-clamp techniques. Levels of calpain and caspases were assessed by western blots and apoptotic cells were stained with Hoechst 33342 and counted.
Cisplatin increases [Ca2+]i concentration-dependently in HeLa-S3 but not in U2-OS cells. This elevation of [Ca2+]i depended on extracellular Ca2+ but was reduced by the IP3 receptor blocker, 2-APB. This effect was not due to a Ca2+ release triggered by Ca2+ entry. Immunostaining showed IP3-receptors (type1-3) at the cellular membrane of HeLa-S3 cells, but not in U2-OS cells. Electrophysiological experiments showed an increased membrane conductance with cisplatin only when Ca2+ was present extracellularly. Increase of [Ca2+]i was related to the activation of calpain but not caspase-8 and triggered apoptosis in HeLa-S3 but not in U2-OS cells.
Conclusions and implications:
Our observations on the activation of IP3-receptors, calcium entry and apoptotic rate by cisplatin in specific carcinogenic cells might open new possibilities in the treatment of some forms of cancer.
British Journal of Pharmacology (2007) 151, 1176–1186; doi:10.1038/sj.bjp.0707335