MCM2 and breast cancer: In our current study we aimed to further investigate the correlation between these nuclear protein markers either expressed throughout (Ki67, MCM2), from post G1 (Cyclin A) or in M-phase (PHH3) of the cell cycle and the routinely examined clinicopathological factors of breast cancers undergoing PST (i.e. histological type, tumor grade, cTNM stage, biological behavior and tumor subtypes).