Overexpression of G9a and MCM7 in oesophageal squamous cell carcinoma is associated with poor prognosis

Aims Histone methyltransferase G9a has been primarily understood as a co‐repressor of gene expression, but it has been shown that G9a also positively regulates nuclear receptor‐mediated transcription. MCM7, a critical component of the DNA replication licensing complex, is amplified and overexpressed in a variety of human malignancies. The objectives of the present study were to study the relationship between the expression of G9a and MCM7 and the pathological grade, clinical stage and prognosis of oesophageal squamous cell carcinoma (OSCC). Methods and results We collected 139 formalin‐fixed and paraffin‐embedded tissues from patients with OSCC and surveyed them by tissue microarray‐based immunohistochemical staining. Associations between the expression of MCM7 and G9a and clinicopathological parameters and prognosis of OSCC were examined. From tissue microarray immunohistochemistry staining results, we found that nuclear staining intensity for MCM7 and G9a was associated with histological grade (both P