BACKGROUND: Resistance to radiation therapy remains a serious impediment to @entity5 therapy. We previously reported heterogeneity for clonogenic survival when testing in vitro radiation resistance among single-cell derived clones from a @entity1 @entity5 stem cell model (hMSC). Here we aimed to determine whether this heterogeneity persisted in @entity5 established from these clones, and whether the response to radiation treatment was principally governed by cell-intrinsic qualities or by factors pertaining to the @entity5 microenvironment, such as the degree of @entity519 and vascularization. METHODS: Immune-deficient female @entity19 were implanted on the backs with cells from one of the clones. The subsequent @entity5 were subjected to either radiation treatment or had the @entity5 microenvironment assayed, when they reached 400 mm  . Radiation was given as a single fraction of 0-15 Gy and the degree of @entity5 control and time to three times the treatment volume were noted. Tumours used for the microenvironmental assay had intratumoral @entity519 measured by the Eppendorf @entity26 electrode and @entity12184 staining, and the extent of vascularization determined by a microvasculature density assay using endothelial-specific staining. RESULTS: All microenvironmental assays indicated a similar degree of @entity519 and vascularization for the selected clones. Nonetheless, the @entity5 responded differently to radiation treatment since the @entity69864 clone displayed @entity5 control at 5, 10 and 15 Gy, whereas @entity5 control was not seen below 15 Gy with the CE8 clone. CONCLUSION: For @entity5 that displayed similar degrees of oxygenation and vascularization, the clone-specific in vitro radiation resistance could predict the in vivo response to radiation treatment. These results favor the hypothesis that intrinsic genetic factors can govern radiation resistance in this @entity5 stem cell model.

Tumour microenvironment and radiation response in sarcomas originating from tumourigenic XXXX mesenchymal stem cells.

@entity1 :: ('9606', 'Species') :: ['human'] @entity69864 :: ('680', 'Gene') :: ['BB3'] @entity5 :: ('MESH:D009369', 'Disease') :: ['mesenchymal cancer', 'cancer', 'tumours', 'tumour'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity519 :: ('MESH:D000860', 'Disease') :: ['hypoxia'] @entity12184 :: ('MESH:C033815', 'Chemical') :: ['pimonidazole']
@entity1 :: (9606,Species) :: ['human']
