GCNT2 and breast cancer: Upregulation of GCNT2 was associated with poor prognosis in breast cancer, prostate cancer, and esophageal carcinoma, with the functions of promoting proliferation, migration, and invasion, acting as an oncogene (23, 24, 26), on the other hand, evidence from other studies supposed the tumor suppressive function of GCNT2 in melanoma (25), endometrial carcinoma (29), and adult T-cell lymphoma/leukemia (28).