Overexpression of TC2N is associated with poor prognosis in gastric cancer

Abstract

<jats:title>Abstract</jats:title> <jats:p>Background Tac2-N (TC2N) is a tandem C2 domain-containing protein, acting as a novel oncogene or suppressor in different kinds of cancers. However, the status of <jats:italic>TC2N</jats:italic> expression and its significance in gastric cancer (GC) is still unclear. The present study is aimed to elucidate the clinicopathological significance and prognostic value of TC2N level in GC. Methods We used sequencing data from the Cancer Genome Atlas (TCGA) database to analyze <jats:italic>TC2N</jats:italic> expression in GC by UALCAN database and Gene Expression Profiling Interactive Analysis tools (GEPIA). <jats:italic>TC2N</jats:italic> expression level in 12 pairs of fresh GC tissues and adjacent nontumorous tissues was detected by quantitative real-time reverse-transcription polymerase chain reaction(RT-PCR)and Western blot(WB) assays. Immunohistochemical (IHC) staining was used to detect TC2N protein expression in Paraffin-embedded tissues in our center. In vitro proliferation, migration and invasion assays were used to evaluate the effect of <jats:italic>TC2N</jats:italic> on functional capability of gastric cancer cells. LinkedOmics was used to identify gene expressions associated with <jats:italic>TC2N</jats:italic>. Results The mRNA and protein expression of <jats:italic>TC2N</jats:italic> in gastric cancer were both significantly higher than normal gastric mucosa. It was also elevated in gastric cancer cells compared with normal gastric epithelium cell. In vitro assays suggested that <jats:italic>TC2N</jats:italic> facilitated proliferation, migration and invasion of gastric cancer cells. Bioinformatic analysis showed a widespread impact of <jats:italic>TC2N</jats:italic> on the transcriptome and a strong interaction with tumor associated genes. We also found that TC2N was an independent prognostic factor for long-term survival in GC patients and its high expression was significantly associated with poor overall survival and recurrence-free survival. Conclusions Our results show that high level of TC2N correlates with poor prognosis in patients with gastric cancer and promotes the development of gastric cancer. Thus, TC2N expression can serve as a prognostic biomarker for patients with gastric cancer.</jats:p>