Endoplasmic reticulum targeting in Ewing’s sarcoma by the alkylphospholipid analog edelfosine
Metrics: PDF 1636 views | HTML 2126 views | ?
Ximena Bonilla1, EL-Habib Dakir1,3, Faustino Mollinedo1,2 and Consuelo Gajate1,2
1 Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
2 Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
3 Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast, UK
Consuelo Gajate, email:
Faustino Mollinedo, email:
Keywords: Ewing’s sarcoma; endoplasmic reticulum; apoptosis; xenograft animal model; ether phospholipid; edelfosine
Received: November 04, 2014 Accepted: April 10, 2015 Published: May 09, 2015
Ewing’s sarcoma (ES) is the second most common bone cancer in children and young people. Edelfosine (1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine) is the prototype of a family of synthetic antitumor compounds, collectively known as alkylphospholipid analogs (APLs). We have found that APLs ranked edelfosine>perifosine>erucylphosphocholine>miltefosine for their capacity to promote apoptosis in ES cells. Edelfosine accumulated in the endoplasmic reticulum (ER) and triggered an ER stress response that eventually led to caspase-dependent apoptosis in ES cells. This apoptotic response involved mitochondrial-mediated processes, with cytochrome c release, caspase-9 activation and generation of reactive oxygen species. Edelfosine-induced apoptosis was also dependent on sustained c-Jun NH2-terminal kinase activation. Oral administration of edelfosine showed a potent in vivo antitumor activity in an ES xenograft animal model. Histochemical staining gave evidence for ER stress response and apoptosis in the ES tumors isolated from edelfosine-treated mice. Edelfosine showed a preferential action on ES tumor cells as compared to non-transformed osteoblasts, and appeared to be well suited for combination therapy regimens. These results demonstrate in vitro and in vivo antitumor activity of edelfosine against ES cells that is mediated by caspase activation and ER stress, and provide the proof of concept for a putative edelfosine- and ER stress-mediated approach forES treatment.
All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 License.