Volume 10 Supplement 1

16th Scientific Symposium of the Austrian Pharmacological Society (APHAR)

Open Access

Long-term regulation of ATP-binding cassette transporters on mRNA and protein level by simvastatin in human rhabdomyosarcoma and neuroblastoma cells

  • Bihter Atil1,
  • Martin Werner1,
  • Evelyn Sieczkowski1,
  • Peter Chiba2 and
  • Martin Hohenegger1Email author
BMC Pharmacology201010(Suppl 1):A12

https://doi.org/10.1186/1471-2210-10-S1-A12

Published: 16 November 2010

Background

Resistance against chemotherapeutics is still a major problem in cancer therapy. One of the mechanisms of multidrug resistance is up-regulation of ATP-binding cassette (ABC) transporters. HMG-CoA reductase inhibitors have been shown to directly inhibit the main representative, ABCB1 (P-glycoprotein). We have previously shown in rhabdomyosarcoma (RD) and neuroblastoma (SH-SY5Y) cells that simvastatin enhanced the intrinsic apoptotic potential of the anthracycline doxorubicin [1, 2]. The aim of the study presented here is to investigate the long-term effect of simvastatin on the expression of ABC-transporters in order to evaluate an adjuvant therapeutic potential of statins in chemotherapy.

Methods

FACS analysis was performed to quantify the accumulation of doxorubicin in RD cells in combinations with simvastatin or verapamil. Several ABC transporters were analysed on mRNA and protein level using real-time PCR and Western blotting in human RD and SH-SY5Y cells. The endogenous level of ABC transporters was also investigated from the livers of simvastatin treated mice.

Results

Here we show that simvastatin led to enhanced accumulation of doxorubicin in RD cells. This was comparable to the effect which was observed for the coadministration of verapamil, a first generation ABCB1 inhibitor, with doxorubicin. ABCB1 was monitored by Western blot analysis of RD and SH-SY5Y cells upon continuous application of simvastatin. In a time and concentration-dependent manner the ABCB1 transporter was less expressed in both cell lines. Interestingly, real-time PCRs revealed a compensatory elevation of mRNAs for various ABC transporters (ABCB1, ABCC1, ABCC6 and ABCG2). Moreover, the augmented mRNA levels of ABCB1 do not result in more transporters on protein level. In vivo, the down-regulation of ABCB1 was confirmed in the liver of simvastatin-treated mice.

Conclusions

Based on our findings, we conclude that simvastatin is able to directly inhibit ABC transporters immediately, but also leads to a long-term down-regulation of various transporters. This feature makes simvastatin a promising candidate for adjuvant chemotherapy to impair transporter-mediated multidrug resistance.

Declarations

Acknowledgements

This work was supported by the Herzfeldersche Familienstiftung and FWF (project P-22385).

Authors’ Affiliations

(1)
Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna
(2)
Institute of Medical Chemistry, Medical University of Vienna

References

  1. Werner M, Sacher J, Hohenegger M: Mutual amplification of apoptosis by statin-induced mitochondrial stress and doxorubicin toxicity in human rhabdomyosarcoma cells. Br J Pharmacol. 2004, 143: 715-724. 10.1038/sj.bjp.0705928.PubMed CentralView ArticlePubMedGoogle Scholar
  2. Sieczkowski E, Lehner C, Ambros PF, Hohenegger M: Double impact on p-glycoprotein by statins enhances doxorubicin cytotoxicity in human neuroblastoma cells. Int J Cancer. 2010, 126: 2025-2035.PubMedGoogle Scholar

Copyright

© Hohenegger et al; licensee BioMed Central Ltd. 2010

This article is published under license to BioMed Central Ltd.

Advertisement