m6A reading protein RBMX as a biomarker for prognosis and tumor progression in esophageal cancer

Background: As a member of m6A methylated binding protein, RNA binding motif protein X-linked (RBMX) has been reported to be associated with tumor invasion, metastasis and prognosis. However, the prognostic significance of RBMX expression in esophageal cancer (ESCA) remains unclear.Methods: Based on the TIMER database, GEPIA database, cBioPortal database, CIBERSORT deconvolution algorithm, String-DB database, LinkedOmics database, etc., the RBMX expression level, mRNA expression level, prognostic relationship, genetic mutation, immune cell infiltration level, protein interaction network, differential co-expression genes and functional enrichment in esophageal carcinoma were analyzed. Immunohistochemistry was used to detect the expression of RBMX in 53 cases of esophageal carcinoma and adjacent esophageal tissues.Results: The RBMX expression in ESCA tissue was significantly higher than that in the normal tissues. The overall survival (OS) of patients with high RBMX expression was significantly lower than that of patients with low expression (P=0.04). The protein encoded by the RBMX gene appeared to copy number amplification, mutation and deep deletion. The expression level of RBMX was positively correlated with the levels of follicular helper T cells, eosinophils and initial B cells (P<0.05). Genes significantly and positively correlated with RBMX expression included HNRNPA1L2, SFRS13A, HNRNPA1, etc., which were mainly enriched in biological processes (BPs) such as cell division, mRNA splicing, RNA binding and mRNA 3'-UTR binding.Conclusions: RBMX may be as a biomarker of poor prognosis of ESCA. RBMX is closely related to the survival and prognosis, genetic mutation and immune cell infiltration of patients with ESCA.