ATP binding cassette subfamily B member 9 (ABCB9) is a prognostic indicator of overall survival in ovarian cancer

Ovarian cancer (OC) is one of the most common gynecological malignancies and owns the highest mortality rate among all gynecological malignant tumors. ATP binding cassette subfamily B member 9 (ABCB9) is an antigen processing-like (TAPL) transporter that has been found to be involved in the development and progression of various malignant tumors in accumulating reports. However, the potential role of ABCB9 in OC has never been reported. In this study, ABCB9 expression was evaluated in normal ovarian tissues and ovarian cancer tissues using The Cancer Genome Atlas (TCGA) database. And the associations between ABCB9 expression and clinical parameters of patients of OC were evaluated by Chi-square tests. Kaplan-Meier analysis and Cox regression analysis were performed to evaluate the prognostic significance of ABCB9. GSEA was performed to explore related signaling pathway. ABCB9 expression levels were significantly decreased in OC compared with normal ovarian tissues (P<.001). Low ABCB9 expression was associated with survival status (P=.0148) in OC. Kaplan-Meier analysis showed that low ABCB9 expression was associated with poor overall survival in OC (P=.0032). Multivariable Cox regression analysis indicated that low ABCB9 expression was an independent prognostic factor (HR 0.64; P=.01) in OC patients. Besides, epithelial mesenchymal transition, UV response, and TGF-beta signaling were enriched in low ABCB9 expression phenotype, respectively, examined by gene set enrichment analysis. These results suggest that ABCB9 is an independent prognostic indicator in OC with certain clinical significance.