Overexpression of ZNF24 in human breast cancer cells leads to decreased VEGF levels and inhibition of tumor angiogenesis. (A) Protein extracts of control MDA-MB-231 cells and cells overexpressing ZNF24 were analyzed by immunoblot. (B) ELISA assays were performed using conditioned medium (left) and cell extracts (right) from control MDA-MB-231 cells or cells overexpressing ZNF24. ***P < .001. (C) In vivo angiogenesis assays were performed by injecting control MDA-MB-231 cells or cells overexpressing ZNF24. Images of tumor nodules were taken 3 days after injection. (D) Numbers of vessels induced by tumor nodules were quantified. pLenti: n = 23 tumor nodules; ZNF24: n = 17 tumor nodules. Data represent means ± SEM. *P < .05. Images were obtained at room temperature using a Leica MZ16F stereomicroscope equipped with a 4× objective with full-open aperature (Meyer Instruments), Retiga EXi camera (QImaging), and Openlab modular imaging software (PerkinElmer).