Deletion of STAT3 reduces cell proliferation, migration, and spheroid formation of ovarian cancer cells in vitro. (A). The proliferation rate of SKOV3, OVCAR3, OVCAR8 and HEY WT/ STAT3 KO cells was evaluated by a cell proliferation assay. The graph displays the cell numbers versus time in h. (B). Migration capability of WT and STAT3 KO cells was determined in a wound-healing assay. The panels on the left show the wound at 0 h after the scratch and the right panels show the wound after 24 h. Scale bar, 100 μm. A bar diagram with statistical analysis is provided in Supplemental Figure S2A. (C). Spheroid formation capability of WT and STAT3 KO cells was determined in a 3D spheroid assay. Spheroid growth was imaged at Days 2, 4 and 6. Scale bar, 100 μm. Luminescence representing cell viability of the same experiment was measured using the CellTiter-Glo® 3D Cell Viability Assay and is presented with statistical analysis in Supplemental Figure S2B.