Phenotypic and functional characterization of endothelial progenitor cells isolated from peripheral blood of renal cell carcinoma patients

Endothelial progenitor cells (EPCs) are mobilized from either bone marrow or arterial walls to restore blood perfusion to ischemic organs and establish the vascular network within growing tumors [1]. The Ca2+ machinery plays a key role in EPC activation and might serve a molecular target for novel therapies of highly angiogenic tumors, such as renal cell carcinoma (RCC) [1]. The Ca2+ toolkit is remodelled in EPCs isolated from RCC patients (RCC-EPCs) as respect to healthy donors [2]. The present study was undertaken to evaluate for the first time the functional properties of EPCs isolated from tumor patients by focusing on RCC-EPCs. We extended our analysis at microscopic level by monitoring the sub-cellular structure of RCC-EPCs relative to their Ca2+ signalling fingerprint. Our results showed a striking functional and ultrastructural difference between RCC-EPCs and their normal counterparts, which might be the basis for designing novel, more specific anti-angiogenic treatments.