%0 Journal Article
%T Expression of aromatase and estrogen receptor alpha in chondrosarcoma, but no beneficial effect of inhibiting estrogen signaling both in vitro and in vivo
%A Danielle Meijer
%A Hans Gelderblom
%A Marcel Karperien
%A Anne-Marie Cleton-Jansen
%A Pancras CW Hogendoorn
%A Judith VMG Bov¨¦e
%J Clinical Sarcoma Research
%D 2011
%I BioMed Central
%R 10.1186/2045-3329-1-5
%X We investigated the protein expression of estrogen receptor alpha (ESR1), androgen receptor (AR), and aromatase in tumor specimens of various chondrosarcoma subtypes, and (primary) chondrosarcoma cultures. Dose-response curves were generated of conventional central chondrosarcoma cell lines cultured in the presence of 17¦Â-estradiol, dihydrotestosterone, 4-androstene-3,17 dione, 4-hydroxytamoxifen, fulvestrant and aromatase inhibitors. In a pilot series, the effect of anastrozole (n = 4) or exemestane (n = 2) treatment in 6 chondrosarcoma patients with progressive disease was explored.We showed protein expression of ESR1 and aromatase in a large majority of all subtypes. Only a minority of the tumors showed few AR positive cells. The dose-response assays showed no effect of any of the compounds on proliferation of conventional chondrosarcoma in vitro. The median progression-free survival of the patients treated with aromatase inhibitors did not significantly deviate from untreated patients.The presence of ESR1 and aromatase in chondrosarcoma tumors and primary cultures supports a possible role of estrogen signaling in chondrosarcoma proliferation. However, our in vitro and pilot in vivo studies have shown no effect of estrogen-signaling inhibition on tumor growth.Chondrosarcomas of bone are malignant cartilage-forming tumors which are highly resistant to conventional chemotherapy and radiotherapy [1,2]. However, recently various promising targets were discovered and the exploration of suitable therapies continues [3,4]. Conventional chondrosarcomas represent about 90% of all chondrosarcomas. Most conventional chondrosarcomas are located in the medullar cavity of the bone and are called central chondrosarcoma. About 15% of conventional chondrosarcomas arise from the surface of bone and are designated as peripheral chondrosarcomas. Conventional chondrosarcomas often show local destructive growth and the high-grade tumors commonly metastasize [5].Besides conventional ch
%U http://www.clinicalsarcomaresearch.com/content/1/1/5