Serum ARID1A acts as a potential diagnostic biomarker for gastric cancer

Background: AT-rich interactive domain 1A gene (ARID1A) had been reported to act as a tumor suppressor in gastric cancer (GC), and reduced expression of ARID1A is significantly correlated with lymphatic invasion and lymph node metastasis. However, its diagnostic value in GC remains unknown. The aim of this study was to detect the expression of serum ARID1A and investigate its diagnostic value in GC. Methods: ARID1A mRNA and protein expression were assessed in 120 GC serum samples and 70 healthy control samples by quantitative real-time polymerase chain reaction (qRT-PCR) and ELISA, respectively. And the association between ARID1A expression and clinicopathologic parameters was evaluated by Chi-square test. To detect the diagnostic value of serum ARID1A, receiver operating characteristic (ROC) curve were established. Results: The expression of ARID1A was down-regulated in GC serum compared to that in healthy controls both at mRNA and protein level (P<0.001), and its low expression was closely related to tumor size, tumor grade, depth of invasion and lymph node metastasis. Besides, ARID1A expression in serum were significantly correlated with the expression of CA19-9 (P=-0.612, P<0.001) and CEA (P=-0.635, P<0.001) in GC. ROC curve showed the AUC of ARID1A for the diagnosis of GC was 0.846 which was higher than that of CA19-9 (0.626) and carcinoembryonic antigen (CEA) (0.706). Conclusions: ARID1A expression decreases in serum of GC patients, and it can be a useful marker for the diagnosis of GC to distinguish GC patients from noncancerous cohorts.