G9a overexpression in omental metastatic lesions compared with the corresponding primary tumors. A. Kaplan–Meier plot of the overall survival of 208 OCa patients, stratified by G9a expression. Low G9a: score of 0 or 1; high G9a: score of 2 or 3. Censored data marked in the plot as short vertical lines. B. Representative microphotographs of immunohistochemical staining of G9a in matched specimens of primary ovarian tumors and metastases from omentum, peritoneum, and lymph node. Scale bar: 100 μm. C. Plots depicting scores according to the immunohistochemical expression of G9a in primary ovarian tumors and metastases. 24 pairs of omental metastases, 7 pairs of peritoneal metastases, and 6 pairs of lymph node metastases were included in the analysis. The scores were calculated by intensity × percentage of stained cells. The association between G9a expression level and metastasis was analyzed using a paired t-test and displayed by box-plot.