CLDN3 and neoplasm: On the other hand, tumor cells may retain and benefit from this binary framework, acquiring a hybrid epithelial/mesenchymal phenotype that was previously observed in OVCAR3 cells, positive for epithelial markers such as Krt18, β-catenin, E-cadherin, and Claudin-3, as well as for the mesenchymal marker Vimentin [44,45].