Knockdown of CoREST1 decreased tumor cell-mediated macrophage migration and activation.

<p><b>(A)</b> F4/80 immunostaining, a marker of macrophage infiltration, was performed in tumors that grew from shCtrl and shCoREST (shCoR) cells. F4/80 expression (red) was quantified using ImageJ using five high power fields of DAPI positive nuclei (blue) from each tumor. Differences were determined using Student’s t-test (n = 3 tumors/group). <b>(B)</b> Migration of HL-60 macrophages was measured in response to conditioned media (CM) from shCoR cells compared to shCtrl cells. HL-60 cells were differentiated into macrophages as described in Materials and Methods. Transwell migration of macrophages was quantified after 4 hr, and differences were determined by ANOVA analysis (n = 3 experiments in triplicate). <b>(C)</b> Migration of HL-60 macrophages was examined in response to CM from shCtrl cells supplemented with vehicle, a blocking antibody to CCL2, or RS504393, an inhibitor for the CCR2 receptor. Transwell migration of macrophages was quantified after 4 hr, and differences were determined by ANOVA analysis (n = 3 experiments in triplicate). <b>(D)</b> HUVEC tube formation was examined in response to CM collected from HL-60 macrophages activated with CM from either shCoR or shCtrl cells. Tubes from 3 high power fields (HPF) were averaged for each condition tested, and differences were determined by ANOVA analysis (n = 3 experiments). <b>(E)</b> HUVEC cell migration was measured following treatment with CM from macrophages activated with CM isolated from either shCoR or shCtrl cells. Wound closure was measured using ImageJ software 6 hr after scratching confluent cells as described in Materials and Methods. Data is expressed as % of wound closure as determined from an average of 10 replicates per condition (n = 3 experiments). <b>(F)</b> Proliferation of HUVEC cells was not altered in response to treatment with CM from macrophages activated with either shCtrl or shCoR CM. HUVEC were counted after 72 hr (n = 3 experiments). Differences were determined by ANOVA analysis (mean±s.d.). Scale bar = 100μm.