The YY1-based prognostics of breast cancers were affected both in terms of OS and DFS by CP2c expression levels, rendering patients with YY1 high and CP2c low expression to have the most favorable prognosis, suggesting that the combination of YY1 and CP2c expression at protein level could also be used as a prognostic biomarker that can effectively predict the disease progression in patients with primary breast cancer. The gene discussed is YY1; the disease is breast carcinoma.