Intracellular trafficking as a determinant of AS-DACA cytotoxicity in rhabdomyosarcoma cells

BMC Cell Biology

Research Article

Tony Huynh¹  Daniel R Catchpoole¹  Steven J Wolf¹  Trevor W Hambley²  Nicole S Bryce²  Laurence PG Wakelin³  Bernard W Stewart⁴ 

[1] Biospecimens Research and Tumour Bank, Children's Cancer Research Unit, The Children's Hospital at Westmead, 2774, Westmead, NSW, Australia;School of Chemistry, University of Sydney, 2006, Sydney, NSW, Australia;School of Medical Sciences, University of New South Wales, 2052, Sydney, NSW, Australia;School of Medical Sciences, University of New South Wales, 2052, Sydney, NSW, Australia;Cancer Control Program, South East Sydney & Illawarra Public Health Unit, 2031, Randwick, NSW, Australia;

关键词: Acidic Vesicle;    Major Vault Protein;    MRP1 Expression;    RH30 Cell;    Rhabdomyosarcoma Cell Line;   

DOI  :  10.1186/1471-2121-12-36

 received in 2011-04-12, accepted in 2011-08-24,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundRhabdomyosarcoma (RMS) is a malignant soft tissue sarcoma derived from skeletal muscle precursor cells, which accounts for 5-8% of all childhood malignancies. Disseminated RMS represents a major clinical obstacle, and the need for better treatment strategies for the clinically aggressive alveolar RMS subtype is particularly apparent. Previously, we have shown that the acridine-4-carboxamide derivative AS-DACA, a known topoisomerase II poison, is potently cytotoxic in the alveolar RMS cell line RH30, but is 190-fold less active in the embryonal RMS cell line RD. Here, we investigate the basis for this selectivity, and demonstrate in these RMS lines, and in an AS-DACA- resistant subclone of RH30, that AS-DACA-induced cytotoxicity correlates with the induction of DNA double strand breaks.ResultsWe show that inhibition of the multidrug-resistance associated protein (MRP1) has no effect on AS-DACA sensitivity. By exploiting the pH-dependent fluorescence properties of AS-DACA, we have characterized its intracellular distribution, and show that it concentrates in the cell nucleus, as well as in acidic vesicles of the membrane trafficking system. We show that fluorescence microscopy can be used to determine the localization of AS-DACA to the nuclear and cytoplasmic compartments of RMS cells grown as spheroids, penetrance being much greater in RH30 than RD spheroids, and that the vesicular signal leads the way into the spheroid mass. EEA1 and Rab5 proteins, molecular markers expressed on early-endosomal vesicles, are reduced by > 50% in the sensitive cell lines.ConclusionTaking the evidence as a whole, suggests that endosomal vesicle trafficking influences the toxicity of AS-DACA in RMS cells.

【 授权许可】

Unknown   
© Wolf et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.