Published online Feb 28, 2017. doi: 10.3748/wjg.v23.i8.1450
Peer-review started: October 5, 2016
First decision: October 20, 2016
Revised: November 20, 2016
Accepted: January 11, 2017
Article in press: January 11, 2017
Published online: February 28, 2017
To detect the expression of Arpin, and determine its correlation with clinicopathological characteristics and the prognosis of gastric cancer (GC) patients.
A total of 176 GC patients were enrolled as study subjects and classified into groups according to different clinicopathological variables. GC mucosal tissues were obtained via surgery. Another 43 paraffin-embedded tissue blocks of normal gastric epithelium (> 5 cm away from the edge of the tumor) were included in the control group. Immunohistochemistry (IHC) for the Arpin and Arp3 proteins was performed on the formalin-fixed, paraffin-embedded GC tissues. Additionally, expression of the Arpin protein in 43 normal gastric tissues was also determined using IHC.
Expression of the Arpin protein in GC was lower than that in normal gastric mucosa (30.68% vs 60.47%, P < 0.001). A χ2 test of the 176 GC samples used for IHC showed that decreased Arpin expression was associated with advanced TNM stage (P < 0.01) and the presence or absence of lymph node metastasis (80.92% vs 35.56%, P < 0.001). Additionally, a significant correlation was observed between the expression of Arpin and the presence of the Arp2/3 complex in GC tissues (χ2 = 30.535, P < 0.001). Moreover, a multivariate Cox regression analysis revealed that Arpin expression [hazard ratio (HR) = 0.551, P = 0.029] and TNM stage (HR = 5.344, P = 0.001) were independent prognostic markers for overall survival of GC patients. Regarding the 3-year disease-free survival (DFS), the recurrence rate of GC patients with low Arpin expression levels (median DFS 19 mo) was higher than that in the high-Arpin-expression group (median DFS 34 mo, P = 0.022).
Low Arpin levels are associated with clinicopathological variables and a poor prognosis in GC patients. Arpin may be regarded as a potential prognostic indicator in GC.
Core tip: Arpin, a newly found Arp2/3 complex inhibitor reported in Nature, in 2013, was shown to restrict the rate of actin polymerization and control cell migration. However, little is known about whether the expression of Arpin is altered in gastric cancer (GC) tissues, and the detailed mechanisms for invasion and metastasis of GC remain unknown. Our research shows that expression level of Arpin is low in GC, and decreased Arpin expression is associated with the characteristics of clinical pathology and poor prognosis of GC patients. It may be regarded as a potential prognosis indicator for clinical outcomes in GC.