ES-2 and CaoV-3 ovarian cancer cells were transfected with HE4 using gene transfection techniques to generate the stably transfected cell lines ES-2-HE4-H, ES-2-HE4-L, CaoV-3-HE4-H and CaoV-3- HE4-L with high and low HE4 gene and protein expression. This evidence concerns the gene WFDC2 and ovarian cancer.