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ObjectiveEsophagogastroduodenoscopy (EGD) is the pivotal procedure in the diagnosis of upper gastrointestinal lesions. However, there are significant variations in EGD performance among endoscopists, impairing the discovery rate of gastric cancers and precursor lesions. The aim of this study was to construct a real-time quality improving system, WISENSE, to monitor blind spots, time the procedure and automatically generate photodocumentation during EGD and thus raise the quality of everyday endoscopy.DesignWISENSE system was developed using the methods of deep convolutional neural networks and deep reinforcement learning. Patients referred because of health examination, symptoms, surveillance were recruited from Renmin hospital of Wuhan University. Enrolled patients were randomly assigned to groups that underwent EGD with or without the assistance of WISENSE. The primary end point was to ascertain if there was a difference in the rate of blind spots between WISENSE-assisted group and the control group.ResultsWISENSE monitored blind spots with an accuracy of 90.40% in real EGD videos. A total of 324 patients were recruited and randomised. 153 and 150 patients were analysed in the WISENSE and control group, respectively. Blind spot rate was lower in WISENSE group compared with the control (5.86% vs 22.46%, p<0.001), and the mean difference was −15.39% (95% CI −19.23 to −11.54). There was no significant adverse event.ConclusionsWISENSE significantly reduced blind spot rate of EGD procedure and could be used to improve the quality of everyday endoscopy.Trial registration numberChiCTR1800014809; Results.

Deregulated miRNAs participate in colorectal carcinogenesis. In this study, miR-218 was found to be downregulated in human colorectal cancer (CRC) by miRNA profile assay. miR-218 was silenced or downregulated in all five colon cancer cells (Caco2, HT29, SW620, HCT116 and LoVo) relative to normal colon tissues. miR-218 expression was significantly lower in 46 CRC tumor tissues compared with their adjacent normal tissues (P < 0.001). Potential target genes of miR-218 were predicted and BMI1 polycomb ring finger oncogene (BMI-1), a polycomb ring finger oncogene, was identified as one of the potential targets. Upregulation of BMI-1 was detected in CRC tumors compared with adjacent normal tissues (P < 0.001) and in all five colon cancer cell lines. Transfection of miR-218 in colon cancer cell lines (HCT116, HT29) significantly reduced luciferase activity of the wild-type construct of BMI-1 3' untranslated region (3'UTR) (P < 0.001), whereas this effect was not seen in the construct with mutant BMI-1 3'UTR, indicating a direct and specific interaction of miR-218 with BMI-1. Ectopic expression of miR-218 in HCT116 and HT29 cells suppressed BMI-1 mRNA and protein expression. In addition, miR-218 suppressed protein expression of BMI-1 downstream targets of cyclin-dependent kinase 4, a cell cycle regulator, while upregulating protein expression of p53. We further revealed that miR-218 induced apoptosis (P < 0.01), inhibited cell proliferation (P < 0.05) and promoted cell cycle arrest in the G2 phase (P < 0.01). In conclusion, miR-218 plays a pivotal role in CRC development through inhibiting cell proliferation and cycle progression and promoting apoptosis by downregulating BMI-1.

Background and study aims: Qualified esophagogastroduodenoscopy (EGD) is a prerequisite for detecting upper gastrointestinal lesions especially early gastric cancer (EGC). Our previous report showed that artificial intelligence system could monitor blind spots during EGD. Here, we updated the system to a new one (named ENDOANGEL), verified its effectiveness on improving endoscopy quality and pre-tested its performance on detecting EGC in a multi-center randomized controlled trial. Patients and methods: ENDOANGEL was developed using deep convolutional neural networks and deep reinforcement learning. Patients undergoing EGD examination in 5 hospitals were randomly assigned to ENDOANGEL-assisted (EA) group or normal control (NC) group. The primary outcome was the number of blind spots. The second outcome includes performance of ENDOANGEL on predicting EGC in clinical setting. Results: 1,050 patients were recruited and randomized. 498 and 504 patients in EA and NC groups were respectively analyzed. Compared with NC, the number of blind spots was less (5.382±4.315 vs. 9.821±4.978, p<0.001) and the inspection time was prolonged (5.400±3.821 min vs. 4.379±3.907 min, p<0.001) in EA group. In the 498 patients from EA group, 196 gastric lesions with pathological results were identified. ENDOANGEL correctly predicted all 3 EGC (1 mucosal carcinoma and 2 high-grade neoplasia) and 2 advanced gastric cancer, with a per-lesion accuracy of 84.69%, sensitivity of 100% and specificity of 84.29% for detecting GC. Conclusions: The results of the multi-center study confirmed that ENDOANGEL is an effective and robust system to improve the quality of EGD and has the potential to detect EGC in real time.

BackgroundmiR-18a is one of the most up-regulated miRNAs in colorectal cancers (CRC) based on miRNA profiling. In this study, we examined the functional significance of miR-18a in CRC.MethodsExpression of miR-18a was investigated in 45 CRC patients. Potential target genes of miR-18a were predicted by in silico search and confirmed by luciferase activity assay and Western blot. DNA damage was measured by comet assay. Gene function was measured by cell viability, colony formation and apoptosis assays.ResultsThe up-regulation of miR-18a was validated and confirmed in 45 primary CRC tumors compared with adjacent normal tissues (p<0.0001). Through in silico search, the 3′UTR of Ataxia telangiectasia mutated (ATM) contains a conserved miR-18a binding site. Expression of ATM was down-regulated in CRC tumors (p<0.0001) and inversely correlated with miR-18a expression (r = -0.4562, p<0.01). Over-expression of miR-18a in colon cancer cells significantly reduced the luciferase activity of the construct with wild-type ATM 3′UTR but not that with mutant ATM 3′UTR, inferring a direct interaction of miR-18a with ATM 3′UTR. This was further confirmed by the down-regulation of ATM protein by miR-18a. As ATM is a key enzyme in DNA damage repair, we evaluated the effect of miR-18a on DNA double-strand breaks. Ectopic expression of miR-18a significantly inhibited the repair of DNA damage induced by etoposide (p<0.001), leading to accumulation of DNA damage, increase in cell apoptosis and poor clonogenic survival.ConclusionmiR-18a attenuates cellular repair of DNA double-strand breaks by directly suppressing ATM, a key enzyme in DNA damage repair.

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Highly fluorogenic tetrazine bioorthogonal probes emitting at near‐infrared wavelengths are in strong demand for biomedical imaging applications. Herein, we have developed a strategy for forming a palette of novel Huaxi‐Fluor probes in situ, whose fluorescence increases hundreds of times upon forming the bioorthogonal reaction product, pyridazine. The resulting probes show large Stokes shifts and high quantum yields. Manipulating the conjugate length and pull–push strength in the fluorophore skeleton allows the emission wavelength to be fine‐tuned from 556 to 728 nm. The highly photo‐stable and biocompatible probes are suitable for visualizing organelles in live cells without a washing step and for imaging of tumors in live small animals to depths of 500 μm by two‐photon excitation.

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