Regulation of DLL4 by miR-30b and miR-30c has relevance in pathophysiologic settings. (A) DLL4 mRNA expression in LECs or KLECs infected with miR-30b and miR-30c–expressing lentiviruses measured by qRT-PCR (means + SEM, n = 3). Expression is relative to LECs infected with empty vector, pSIN_MCS. Differences between pSIN_MCS-infected and pSIN_30b/30c-infected KLECs were significant (*P < .05). (B) DLL4 protein expression in LECs measured by Western blotting. Values indicate intensity of DLL4 antibody ECL plus signal normalized to GAPDH antibody ECL signal and relative to KSHV−/pSIN_MCS+. (C) Left panels: Representative photographs at indicated time points of HUVEC spheroids embedded in matrigel. HUVECs were transfected with mimic before being induced to form spheroids. Photographs were taken on an Axiovert 100 microscope (Zeiss) using an AxioCam (Zeiss) at 5× magnification in phase contrast. Images were acquired using AxioVision (Zeiss). Middle panels: Quantification of total sprouts per spheroid (y-axis) at indicated time points (n = 60). Box plot indicates inter-quartile range, whiskers indicate total range, black line denotes median. Sprouts were counted using Adobe Photoshop CS2. The difference between NTC-transfected and miR-30b–transfected cells was significant (***P < .001). Right panels: Quantification of average sprout length (y-axis; means + SEM, n = 20). Average sprout length was measured using the segmented lines tool in Image J (National Institutes of Health) and are displayed on the y-axis as ×100 μm. Five sprouts were measured per spheroid. The difference between NTC-transfected and miR-30b–transfected cells was significant (***P < .001).