Expression of Lysine-specific demethylase 1 in human epithelial ovarian cancer

Lysine-specific demethylase 1(LSD1) is implicated in the tumorigenesis and progression in various cancers. However, the expression of LSD1 in epithelial ovarian cancer and its clinical significance has not been examined in detail. Immunohistochemical was used to detect the expression of LSD1 in normal ovarian epithelial tissues, cystadenoma, borderline cystadenoma, and cystadenocarcinoma. Next, the correlations between expression of LSD1 and clinicopathological features was assessed in 96 species of serous cystadenocarcinoma and 36 species of mucinous cystadenocarcinoma. Immunohistochemical results showed that the expression of LSD1 was gradually increased from benign cystadenoma and borderline cystadenoma to cystadenocarcinoma. The positive ratio of LSD1 expression was 50% in normal ovarian epithelial tissues, 72% in serous cystadenoma, 73% in mucinous cystadenoma, 82% in borderline serous cystadenoma, 83% in borderline mucinous cystadenoma, 94% in serous cystadenocarcinoma and 92% in mucinous cystadenocarcinoma, respectively. LSD1 expression levels were associated with International Federation of Gynecology and Obstetrics stage and lymphatic metastasis in both serous and mucinous cystadenocarcinoma samples. Kaplan-Meier curves suggested that overall survival time of patients with high LSD1 expression was significantly shorter than that of patients with low LSD1 expression. Multivariate Cox proportional hazard regression indicated that higher LSD1 expression was a significant independent predictor of poor survival of EOC patients (P = 0.016). These results suggest that LSD1 may be involved in carcinogenesis and progression with promising therapeutic potential for epithelial ovarian cancer.