Circulating endothelial progenitor cells in gynaecological cancer

Objectives: To compare the frequency and absolute numbers of circulating endothelial progenitor cells (EPCs) in healthy control subjects and patients with gynaecological cancer, and to test the hypothesis that cancer treatment lowers EPC numbers. Methods: Patients with cervical or ovarian cancer and healthy control subjects provided peripheral blood samples for the isolation of mononuclear cells. EPCs were identified by quadruple immunofluorescence staining and flow cytometry as CD45^-/CD34⁺/CD133⁺/vascular endothelial growth factor receptor 2 (VEGFR2)⁺ cells. Results: In total, 28 participants were enrolled. Circulating EPCs were present at higher frequencies (and in greater absolute numbers) in patients with cervical or ovarian cancer (n=14) than in controls (n=14). Concurrent chemoradiation therapy or surgery significantly reduced the frequency and number of EPCs in patients with gynaecological cancer, compared with pretreatment levels. Conclusions: EPC levels decline throughout cancer treatment; their measurement may therefore be a useful surrogate marker to monitor treatment response.