The implication of Synemin gene on expression and prognostic significance in gastric cancer based on bioinformatics

Abstract Objective： Here, we explored the expression of SYNM by means of Gene Expression Omnibus (GEO) and investigated its prognostic significance as well as potential functions in gastric cancer (GC). Methods： Toward this goal, differential gene expression analysis, univariate Cox regression, Lasso regression, best subset regression, Gene Set Enrichment Analysis (GSEA) and multivariate Cox regression were employed in GEO. For further verification, the pathological tissues of patients with gastric cancer were collected and analyzed. The expression of SYNM in GC tissues was verified by qRT-PCR, Western blotting and immunohistochemistry. Kruskal-Wallis test was used to analyze the correlation between SYNM expression and clinical characteristics. Kaplan-Meier analysis, univariate and multivariate Cox regression analysis were applied to analyzed prognostic. Results： SYNM is underexpressed in GC in public datasets and clinical samples ( P < 0.01); Its expression was significantly correlated with Lauren typing, T, N, M and clinical staging ( P < 0.05). Patients with high SYNM expression had poor prognosis ( P < 0.01) and it was an independent prognostic factor for GC (p = 0.01). The high expression of SYNM mRNA was enriched in Extracellular matrix (ECM) receptor interaction, leukocyte transendothelial migration and Transforming growth factor β (TGF – β) signaling pathway, and CD4+ memory T cells resting were abundant. Conclusion： SYNM was low expression in GC and it might promote the malignant development and immune evasion of GC, and patients with high expression of SYNM predicted a good prognosis.