title: Cilengitide inhibits metastatic bone colonization in a nude rat model.
abstract: Integrins αvβ3 and αvβ5 are considered to play an important role in the pathogenesis of breast cancer bone metastases. This study investigates the effects of the αvβ3/αvβ5 integrin-specific inhibitor cilengitide during early metastatic bone colonization. The impact of cilengitide on the migration, invasion and proliferation of MDA-MB-231 human breast carcinoma cells as well as on bone resorption by osteoclasts was investigated in vitro. For in vivo experiments, nude rats were treated with cilengitide for 30 days starting one day after site-specific tumor cell inoculation in the hind leg, and the course of metastatic changes in bone was followed using flat-panel volumetric computed tomography (VCT) and magnetic resonance imaging (MRI). Vascular changes in bone metastases were investigated using dynamic contrast-enhanced (DCE-) MRI-derived parameters amplitude A and exchange rate coefficient kep. In vitro, cilengitide treatment resulted in a decrease in proliferation, migration and invasion of MDA-MB-231 cells, as well as of osteoclast activity. In vivo, the development of bone metastasis in the hind leg of rats was not prevented by adjuvant cilengitide treatment, but cilengitide reduced the volumes of osteolytic lesions and respective soft tissue tumors of developing bone metastases as assessed with VCT and MRI, respectively. DCE-MRI revealed significant changes in the A and kep parameters including decreased relative blood volume and increased vessel permeability after cilengitide treatment indicating vessel remodeling. In conclusion, during early pathogenic processes of bone colonization, cilengitide treatment exerted effects on tumor cells, osteoclasts and vasculature reducing the skeletal lesion size of experimental skeletal metastases.
authors: Department of Medical Physics in Radiology, German Cancer Research Center, 69120 Heidelberg, Germany.
authors: Maren
authors: M
authors: Bretschi
authors: Maximilian
authors: M
authors: Merz
authors: Dorde
authors: D
authors: Komljenovic
authors: Martin R
authors: MR
authors: Berger
authors: Wolfhard
authors: W
authors: Semmler
authors: Tobias
authors: T
authors: Bäuerle
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000517:prevention & control* / Q000556:secondary*; D001862:Bone Resorption / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009361:Neoplasm Invasiveness; D010010:Osteoclasts / Q000378:metabolism / Q000473:pathology; D051381:Rats; D011923:Rats, Nude; D012910:Snake Venoms / Q000494:pharmacology*; D023041:Xenograft Model Antitumor Assays
chemical_list: D012910:Snake Venoms; C422910:Cilengitide