CLDN3 and ovarian cancer: Taken together, these results indicated that the expression of claudins, including claudin-3, -4 and -7, is higher in chemoresistant than in chemosensitive ovarian cancer cells and that their high expression is associated with increased resistance to chemotherapy in ovarian cancer, highlighting the fact that targeting these claudins using CPE or siRNA may increase the sensitivity of ovarian cancer cells to chemotherapy.