It has been shown that the serum concentration of VEGF correlates with the concentration of EPCs in cancer tissue.38 We recently observed a correlation of serum VEGF and cEPC in lung cancer patients.14 Fürstenberger et al. observed in patients with primary breast cancer that Ang-2 and VEGF were concomitantly increased with cEPC, suggesting a mobilization by neoadjuvant chemotherapy.39 Here, ANGPT2 is linked to cancer.