High SLC4A11 expression is an independent predictor for poor overall survival in grade 3/4 serous ovarian cancer.

In this study, we aimed to examine the expression of SLC4A11 in ovarian cancer and in normal ovarian tissues, its prognostic value and the possible mechanism of its dysregulation. Bioinformatic analysis was performed by using data from the GEO datasets, the Cancer Genome Atlas-Ovarian Cancer (TCGA-OV) and the Human Protein Atlas (HPA). Results showed that SLC4A11 was upregulated in ovarian cancer compared with normal ovarian epithelial tissues. In patients with primary serous ovarian cancer in TCGA-OV, the cases with lymphatic invasion (N = 133) had significantly higher SLC4A11 expression than those without lymphatic invasion (N = 77) (p = 0.0069). High SLC4A11 expression was consistently associated with worse overall survival (OS). Univariate and multivariate analysis confirmed that high SLC4A11 expression was an independent prognostic factor for poor OS in grade 3/4 (G3/G4) tumors (HR = 1.416, 95%CI: 1.098-1.824, p = 0.007). 320 out of 578 (55.4%) ovarian cancer cases had SLC4A11 amplification. High methylation group had a significantly lower level of SLC4A11 expression. Based on these findings, we infer that high SLC4A11 expression is an independent predictor for poor OS in grade 3/4 serous ovarian cancer. Both DNA amplification and hypomethylation contribute to its upregulation in ovarian cancer.