Our previous study showed that ovarian cancer cells induced to have mesenchymal phenotype either by overexpression of EMT transcription factors (ZEB1, SNAI1, and SNAI2), oncogenes (H-Ras v12), or by drug resistance were all consistently more deformable than cells with epithelial phenotype (Qi et al., 2015). This evidence concerns the gene ZEB1 and ovarian cancer.