PTTG1 and breast cancer: Previous studies suggested that UBE2C expression was accompanied by that of other biomarkers such as AZGP-1, prolactin-inducible protein, and S100A8 [29] or with pituitary tumor-transforming 1 (PTTG1), Survivin and thymidin kinase 1 [30], which might improve outcome prediction in breast cancer.