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Background:Epstein-Barr virus (EBV)is associated with various human lymphoid and epithelial malignancies such as Burkitt's lymphoma,nasopharyngeal carcinoma and gastric carcinoma. LMP2A,a virus-encoded latent membrane protein is expressed in a portion of EBV-associated gastric carcinoma (EBVaGC)and has been shown to be related with the tumorigenesis and progression of EBVaGC. Aims:To explore the effect of LMP2A silencing on growth of EBVaGC cells in vitro by using a lentivirus-mediated RNA interference (RNAi)to inhibit LMP2A gene expression. Methods:A lentivirus vector pGCSIL-LMP2A-shRNA-LV and a negative control vector were constructed and transfected into the EBVaGC cell line GT38. Real-time PCR and Western blotting were used to determine the inhibitory effect of the lentivirus vector;CCK-8 assay,colony formation assay and flow cytometry were employed to assess the cell growth,cell cycle and apoptosis of GT38 cells. Results:In GT38 cells transfected with LMP2A-shRNA-LV,the expression level of LMP2A mRNA was decreased by 65. 4%,and that of LMP2A protein was reduced by 50. 8%;the cell proliferation was inhibited,the colony formation ability was suppressed,the percentage of cells in G0 / G1 phase and apoptotic rate were increased when compared with those transfected with negative control vector or without transfection (P < 0. 05). Conclusions:Lentivirus-mediated RNAi is effective for silencing LMP2A gene expression,subsequently inhibiting the growth of EBVaGC cells,inducing G0 / G1 phase arrest and enhancing cell apoptosis in vitro. LMP2A is supposed to be a potential target for gene therapy of EBVaGC.
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Objective To investigate the value of intervening part (IP)ratio under magnifying endoscopy with narrow-band imaging (ME-NBI )in the diagnosis of early gastric neoplastic lesions. Methods From September 2012 to May 2015 ,a total of 124 patients with suspected superficial gastric neoplastic lesions under white light endoscope (WLI)were enrolled,87 male with mean age of (63.2 ± 7.9)years old and 37 female with mean age of (62.6±8.2)years old.All the enrolled patients received precision endoscopy examination,which were observed under WLI at first followed by ME-NBI.Vessel, surface classification and IP features of the lesions under WLI and ME-NBI were recorded,and targeted biopsies were performed.Patients received endoscopic submucosal dissection (ESD)or surgery according to lesions features,histopathological results.Agreement rate between WLI,VS classification with IP ratio and the histopathological results were analyzed.Chi-square test was performed for rate comparision Receiver operator characteristic (ROC)curve was drawn to compare the diagnostic accuracy in early gastriccancer (EGC)between WLI and ME-NBI.Results Among the 124 patients,a total of 118 patients completed precision endoscopy examination.A total of 162 lesions were detected,and 161 of which were analyzed.A total of 84 low grade intraepithelial neoplasia (LGIN),63 high grade intraepithelial neoplasia (HGIN), seven mucosal cancer and seven submucosal cacinoma were detected. The incidences of demarcation line (32.1 %(27/84)vs 96.1 %(74/77)),irregular microsurface pattern (45 .2%(38/84)vs 87.0%(67/77)),irregular-microvascular pattern (16.7%(14/84)vs 62.3%(48/77 )),increased gland tube density (48.8%(41/84)vs 85 .7%(66/77 ))and increased microvessel density (21 .4%(18/84)vs 80.5 %(62/77))of non-cacinoma lesions (LGIN)were significantly lower than those of cacinoma lesions (including HGIN, mucosa cancer and submucosa cacinoma ), and the differences were statistically significant (χ2 =67.6,29.1 ,33.5 ,22.9,53.7,all P <0.05).The sensitivities of WLI and ME-NBI in EGC diagnosis were 89.6% and 94.8%,respectively;the specificities were 61 .9% and 83.3%, respectively,area under curve (AUC)were 0.84 and 0.93,respectively.The diagnostic accuracy of ME-NBI in early gastric cancer was higher than that of WLI,and the difference was statistically significant (χ2 =49.0, P <0.01).The sensitivities of vessel plus surface (VS)classification and VS classification with IP ratio were 90.9% and 94.8%,respectively;and the specificities were 81 .0% and 83.3%,respectively;AUC were 0.89 and 0.93,respectively.The diagnostic sensitivity of vessel classification with IP ratio was higher than that of simple vessel classification,and the differnce was statistically significant (χ2 =41 .0, P <0.01).Conclusion Compared with WLI,the diagnostic accuracy of ME-NBI is higher in gastric superficial neoplasia lesions,and IP ratio is helpful in diagnosis of gastric superficial neoplasia lesions.
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Background:Esophageal cancer is a commonly seen gastrointestinal malignancy. Early detection of superficial neoplastic lesions is critical for improving the prognosis. Therefore,it is of great importance to explore new endoscopic techniques for increasing the detection rate of early esophageal cancer. Aims:To assess the diagnostic accuracy of targeted biopsy guided by magnifying endoscopy combined with narrow-band imaging(ME-NBI)for suspected superficial lesions in esophagus. Methods:In a prospective cross-over designed trial,65 patients with suspected superficial lesions in esophagus detected by conventional gastroscopy were randomly assigned to group A and group B. Patients in group A received primary white light imaging(WLI)with Lugol’s staining followed by ME-NBI 4-6 weeks later,and patients in group B received primary ME-NBI followed by WLI with Lugol’s staining 4-6 weeks later. Random biopsy was performed in WLI with Lugol’s staining,while targeted biopsy was performed in ME-NBI based on Inoue’s intraepithelial papillary capillary loop (IPCL)classification. Results:A total of 58 patients completed the study and 68 lesions were eligible for statistical analysis. More biopsies were taken in WLI with Lugol’s staining than in ME-NBI(3. 7 vs. 2. 2 per lesion,P 0. 05). Conclusions:ME-NBI-guided targeted biopsy is superior to random biopsy by WLI with Lugol’s staining for detection of superficial neoplastic lesions in esophagus with higher sensitivity and less number of biopsy. It might benefit the follow-up endoscopic treatment.
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ObjectiveTo investigate the biological significance and mechanism of VEGF-C in esophageal tumor development,and correlation of CNTN-1 level with VEGF-C.MethodsThe expression of VEGF-C and its receptors in esophageal squamous cancer cell (ESCC) and in corresponding noncancerous esophageal tissue specimens were detected by real-tithe PCR.Esophageal squamous cancer cell line TE-1 was transinfected by VEGF-C overexpression and gene silencing vectors,respectively,and the relative amount of C/EBP bound to CNTN-1 promoter was determined by quantitative ChIP,to explore the possibility that VEGF-C was involved in development of esophageal cancer through mediating transcription of CNTN-1.ResultsThe mRNA levels of VEGF-C was significantly higher in ESCC than in normal esophageal tissues.VEGF-C expression was significantly increased in VEGF-C-overexpressing TE-1 cells compared to untransfected cells (mock).Cells transfected with either of the VEGF-C targeting shRNA vectors,shRNA-1 and shRNA-2,showed reduced VEGF-C transcripts (P ＜ 0.01 ).Expression levels of VEGF-C and CNTN-1 mRNA correlated significantly with each other.The binding site of C/EBP in CNTN-1 was detected by ChIP,and the relative amount of C/EBP binding to CNTN-1 promoter was significantly increased in TE-1 after transfecting by VEGF-C overexpression vector ( P ＜ 0.05).ConclusionVEGF-C and its receptor are highly expressed in esophageal cancer tissues,which may be associated with ESCC carcinogenesis and development.VEGF-C may influence on growth and migration in TE-1 cells through CNTN-1.