In addition to confirmation of the increased expression of Dll4, Notch 1, or Notch 3 in ovarian tumor tissues, Wang et al. have found that Dll4 was positively correlated with VEGFR1 expression, and Notch 1 was positively associated with VEGFR2 expression and microvessel density in the ovarian cancer tissues [31]. This evidence concerns the gene DLL4 and ovarian cancer.