WFDC2 and atypical endometrial hyperplasia: In the first study, Deng et al. [61] evaluated the co-expression of HE4 protein and Annexin A2 (ANXA2), a protein significantly increased in malignant tumors, in 84 endometrial cancer samples, 30 cases of atypical endometrial hyperplasia, and 18 healthy endometrial specimens.