SAMD4B: a novel prognostic biomarker of endometrial carcinoma.

Background: Endometrial cancer (EC) is a prevalent gynecologic cancer; however, the EC risk factors based on alterations in individual gene expression require further investigation. Sterile alpha motif domain-containing protein 4 (SAMD4) is an evolutionary conserved gene that has been linked to various cancers. Here, we aimed to investigate the relationship between SAMD4B expression and EC. Methods: Microarray data of SAMD4B were obtained from the Gene Expression Omnibus datasets GSE17025 and GSE29981; RNA sequencing data and clinical and survival data were downloaded from the Cancer Genome Atlas cohort. The datasets were analyzed using Affymetrix GeneChipTM Human Genome U133 Plus 2.0 Array, and the patients were divided into four sub-groups based on DNA polymerase epsilon mutation, microsatellite instability/mismatch repair deficiency, TP53 gene mutation, and microsatellite stability status. Results: SAMD4B expression was higher in EC tissues than that in normal endometrial tissues. SAMD4B overexpression was associated with poor overall survival (OS) of patients with EC [P<0.001, hazard ratio (HR) =2.254, 95% confidence interval (CI): 1.447-3.510]. Cox regression analysis showed that high SAMD4B expression, clinical stage, histologic grade, and positive cytology were independent prognostic factors for poor OS in patients with EC. In the subgroup analysis, SAMD4B mean expression was the highest in the TP53 mutation group, which showed the worst OS. Conclusions: SAMD4B may serve as a novel prognostic biomarker for patients with EC.