Prognostic Significance of TM4SF1 and DDR1 Expression in Ovarian Cancer

Abstract Background: TM4SF1 and DDR1 are expressed in many cancers, but their expression in ovarian cancer and the relationship between their expression and patient prognosis are still unclear. The present study aimed to explore the expression of TM4SF1 and DDR1 as well as their relationship with the prognosis of ovarian cancer.Methods: The Oncomine database and gene expression profile interactive analysis (GEPIA) were used to compare the different expression levels of TM4SF1 and DDR1 in ovarian cancer, and Kaplan–Meier plotter was used to analyse the relationship between gene expression and patient prognosis. The interacting proteins of TM4SF1 and DDR1 were analysed by STRING, which is an online protein interaction analysis tool, and enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathways was conducted for these interacting proteins. Immunohistochemical staining was performed to detect the expression of TM4SF1 and DDR1 protein in ovarian cancer tissue and to analyse the relationship between the expression and prognosis.Results: Database and clinical sample analyses showed that the expression levels of TM4SF1 and DDR1 were significantly higher in ovarian cancer and that TM4SF1 and DDR1 were coexpressed in some cases. STRING analysis found that the TM4SF1 and DDR1 proteins had an interaction relationship. The overall survival (OS) and progression-free survival (PFS) of ovarian cancer patients with TM4SF1 and DDR1 coexpression were significantly shorter than those of patients lacking TM4SF1 and DDR1 coexpression. Multivariate analysis showed that TM4SF1 and DDR1 protein coexpression was an independent prognostic factor.Conclusions: TM4SF1 and DDR1 proteins were coexpressed in some ovarian cancer tissues and were considered adverse prognostic factors for ovarian cancer. Our findings suggested that there might be an interaction or mutual regulatory mechanism of TM4SF1 and DDR1.