Primary research

Preclinical evaluation of the antineoplastic action of 5-aza-2'-deoxycytidine and different histone deacetylase inhibitors on human Ewing's sarcoma cells

Annie Hurtubise¹ , Mark L Bernstein² and Richard L Momparler¹

¹  Département de pharmacologie, Université de Montréal, Centre de recherche pédiatrique, and Service d'hématologie-oncologie, Hôpital Sainte-Justine, 3175 Côte Sainte-Catherine, Montréal, Québec, H3T 1C5, Canada

²  Hematology-Oncology, IWK Health Center and Dalhousie University, Halifax, Nova Scotia, Canada

author email corresponding author email

Cancer Cell International 2008, 8:16doi:10.1186/1475-2867-8-16

Published:	17 November 2008

Abstract

Background

Most patients with advanced Ewing's sarcoma (EWS) respond poorly to conventional chemotherapy, indicating the need for new treatment approaches. Epigenetic events, such as promoter hypermethylation and chromatin histone deacetylation, silence the expression of tumor suppressor genes (TSGs) and play an important role in tumorigenesis. These epigenetic changes can be reversed by using 5-aza-2'-deoxycytidine (5AZA-CdR), a potent inhibitor of DNA methylation, in combination with an inhibitor of histone deacetylase (HDAC).

Results

Here, we used a clonogenic assay to evaluate the in vitro antineoplastic activity of 5AZA-CdR in combination with different HDAC inhibitors on EWS cells. We observed that the HDAC inhibitors, MS-275, trichostatin-A, phenylbutyrate, LAQ824 and depsipeptide, enhanced the antineoplastic action of 5AZA-CdR on EWS cells. The combination of 5AZA-CdR and MS-275 showed marked synergy, and was correlated with significant reactivation of the expression of two TSGs, E-cadherin and tumor suppressor lung cancer-1 (TSLC1), in a EWS cell line.

Conclusion

These results suggest the value of future clinical studies investigating the combination of 5AZA-CdR and MS-275 in patients with advanced EWS.