MKI67 and ductal breast carcinoma in situ: As a result, NEK2A mRNA expression was associated with certain molecular subtypes, like Estrogen Receptor (ER), Progesterone Receptor (PR), and Ki-67 immunoreactivity (P < 0.05) in breast ductal carcinoma in situ (DCIS) tissue; moreover, in IDC tissue, NEK2A expression was associated with histological grade, lymph node metastasis, molecular subtypes, C-erbB-2 expression, and Ki-67 expression (P < 0.05) [49].