CXCR6 predicts poor prognosis in gastric cancer and promotes tumor metastasis through epithelial-mesenchymal transition.

Chemokines and their receptors have been confirmed to be involved in several types of cancer. However, little is known concerning the role of CXCL16 and its receptor CXCR6 in gastric cancer (GC) progression and metastasis. In the present study, expression of CXCL16 and CXCR6 in GC tumor and peritumoral tissues was detected by immunohistochemistry (IHC) in a cohort of 352 GC patients who underwent gastrectomy, and the correlation between CXCL16/CXCR6 expression and clinicopathological characteristics was further analyzed. To evaluate the function of CXCR6, we overexpressed and knocked down CXCR6 in GC cell lines. Results showed that expression of CXCR6, but not CXCL16, was significantly upregulated in GC tumor tissues, and was significantly correlated with lymph node and distant metastases, and advanced clinical stage in the GC patients. Survival analysis showed that large tumor size (>5 cm), elevated preoperative serum carcinoembryonic antigen (CEA) level, advanced TNM stage and high CXCR6 expression indicated worse overall survival (OS) and disease-free survival (DFS) in GC, and CXCR6 was an independent predictor for both OS and DFS in GC. In vitro experiments showed that CXCR6 overexpression induced cell migration and invasion ability, and promoted epithelial-mesenchymal transition of GC cells by upregulation of mesenchymal markers and inhibition of epithelial markers. In contrast, knockdown of CXCR6 in GC cells resulted in inhibition of cell proliferation, migration and invasion ability, and reversal of epithelial-mesenchymal transition (EMT) phenomenon. Our results demonstrated that CXCR6 is an independent prognostic factor for poor survival in GC patients, and may promote GC metastasis through EMT.

CtBP2 overexpression promotes tumor cell proliferation and invasion in gastric cancer and is associated with poor prognosis.

C-terminal binding protein-2 (CtBP2), a transcriptional corepressor, has been reported to correlate with tumorigenesis and progression and predict a poor prognosis in several human cancers. However, few studies on CtBP2 in gastric cancer (GC) have been performed. In this research, we evaluated the correlations between CtBP2 expression and the clinicopathological characteristics, as well as prognosis of GC patients. The effects of silencing CtBP2 expression on GC cells biology activity were also assessed. The results showed that CtBP2 was overexpressed in GC tissues and closely correlated with poor differentiation, advanced tumor stage and poor prognosis in GC patients. CtBP2 induced epithelial-to-mesenchymal transition (EMT) and repressed PTEN to increase proliferation rate, migration, and invasion in GC cells. Silencing CtBP2 inhibited GC growth in nude mice model. In conclusion, CtBP2 is overexpressed in GC and may accelerate GC tumorigenesis and metastasis, which could represent an independent prognostic marker and promising therapeutic target for GC.

Marital status and survival in patients with gastric cancer.

The objective of this study is to examine the impact of marital status on incidence of metastasis at diagnosis, receipt of surgery, and cause-specific survival (CSS) in patients with gastric cancer (GC). Research data is extracted from The Surveillance, Epidemiology, and End Results (SEER) database, and 18,196 patients diagnosed with GC from 2004 to 2010 are involved. Effects of marital status on incidence of metastasis at diagnosis, receipt of surgery, and CSS are determined using multivariable logistic regression and multivariable Cox regression models, as appropriate. Single GC patients have a higher incidence of metastasis at diagnosis than married patients, while the differences between divorced/separated patients or widowed patients and married patients are not significant. Among those without distant metastasis, single patients, divorced/separated patients, and widowed patients are much less likely to accept surgery compared with married patients. Finally, in the whole group of 18,196 GC patients, single patients, divorced/separated patients, and widowed patients have shorter CSS compared with married patients, even in each of the TNM stage. Marriage had a protective effect against undertreatment and cause-specific mortality (CSM) in GC. Spousal support may contribute to higher rate of surgery receipt and better survival in patients with GC.

Prognostic factors and survival in patients with gastric stump cancer.

AIM: To elucidate the clinicopathological characteristics and prognostic factors of gastric stump cancer (GSC). METHODS: The clinical data for 92 patients with GSC were collected at Fudan University Shanghai Cancer Center. The prognostic factors were analyzed with Cox proportional hazard models. RESULTS: GSC tended to occur within 25 years following the primary surgery, when the initial disease is benign, whereas it primarily occurred within the first 15 years post-operation for gastric cancer. Patients with regular follow-up after primary surgery had a better survival rate. The multivariate Cox regression analysis revealed that Borrmann type I/II (HR = 3.165, 95%CI: 1.055-9.500, P = 0.040) and radical resection (HR = 1.780, 95%CI: 1.061-2.987, P = 0.029) were independent prognostic factors for GSC. The overall 1-, 3-, and 5-year survival rates of the 92 patients were 78.3%, 45.6% and 27.6%, respectively. The 1-, 3-, and 5-year survival rates of those undergoing radical resection were 79.3%, 52.2%, and 37.8%, respectively. The 5-year survival rates for stages I, II, III, and IV were 85.7%, 47.4%, 16.0%, and 13.3%, respectively (P = 0.005). CONCLUSION: The appearance of GSC occurs sooner in patients with primary malignant cancer than in patients with a primary benign disease. Therefore, close follow-up is necessary. The overall survival of patients with GSC is poor, and curative resection can improve their prognosis.

Three-port laparoscopic exploration is not sufficient for patients with T4 gastric cancer.

Gastric cancer continues to be a leading cause of cancer death. The majority of patients with gastric adenocarcinoma in China present with advanced disease. Ruling out unresectable cancers from an unnecessary ''open'' exploration is very important. The aim of this study was to assess the value of five-port anatomical laparoscopic exploration in T4 gastric cancer in comparison with three-port laparoscopic exploration and laparotomy exploration. We conducted a retrospective study on 126 patients with T4 stage scheduled for D2 curative gastrectomy based on computed tomography (CT) staging at Department of Gastric Cancer and Soft Tissue Sarcoma, Fudan University Shanghai Cancer Center, from Apr. 2011 to Apr. 2013. Laparotomy exploration (Group I), three-port laparoscopic exploration (Group II) or five-port anatomical laparoscopic exploration (Group III) were performed prior to radical gastrectomy. Accuracy rate for feasibility of D2 curative gastrectomy in laparotomy exploration and five-port anatomical laparoscopic exploration groups was higher than that in the three-port laparoscopic exploration group. Five-port anatomical laparoscopic exploration group had the highest accuracy resection rate (Group I vs Group II vs Group III,92.6% vs78.6% vs 97.7%; p<0.05) and shorter length of hospitalization (Group I vs Group II vs Group III, 9.58±4.17 vs 6.13±2.85 vs 5.00±1.81; p<0.001). Three-port laparoscopic exploration has low accuracy rate for assessing feasibility of D2 curative gastrectomy and five-port anatomical laparoscopic exploration should be performed on patients with T4 gastric cancer.