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Mis-regulated RNA modifications promote the processing and translation of oncogenic mRNAs to facilitate cancer progression, while the molecular mechanisms remain unclear. Here we reveal that tRNA m7G methyltransferase complex proteins METTL1 and WDR4 are significantly up-regulated in esophageal squamous cell carcinoma (ESCC) tissues and associated with poor ESCC prognosis. In addition, METTL1 and WDR4 promote ESCC progression via the tRNA m7G methyltransferase activity in vitro and in vivo. Mechanistically, METTL1 or WDR4 knockdown leads to decreased expression of m7G-modified tRNAs and reduces the translation of a subset of oncogenic transcripts enriched in RPTOR/ULK1/autophagy pathway. Furthermore, ESCC models using Mettl1 conditional knockout and knockin mice uncover the essential function of METTL1 in promoting ESCC tumorigenesis in vivo. Our study demonstrates the important oncogenic function of mis-regulated tRNA m7G modification in ESCC, and suggest that targeting METTL1 and its downstream signaling axis could be a promising therapeutic target for ESCC treatment. Deregulation of METTL1-mediated N7- methylguanosine tRNA modification can promote oncogenesis. Here, the authors report that this modification regulates the translation of proteins in both the mTOR and negative regulators of autophagy pathways, resulting in the progression of esophageal squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

Background: Accurate estimation of the long-term risk of recurrence in patients with non-metastatic colorectal cancer (CRC) is crucial for clinical management. Histology-based deep learning is expected to provide more abundant information for risk stratification. Methods: We developed and validated a weakly supervised deep-learning model for predicting 5-year relapse-free survival (RFS) to stratify patients with different risks based on histological images from three hospitals of 614 cases with non-metastatic CRC. A deep prognostic factor (DL-RRS) was established to stratify patients into high and low-risk group. The areas under the curve (AUCs) were calculated to evaluate the performances of models. Results: Our proposed model achieves the AUCs of 0.833 (95% CI: 0.736–0.905) and 0.715 (95% CI: 0.647–0.776) on validation cohort and external test cohort, respectively. The 5-year RFS rate was 45.7% for high DL-RRS patients, and 82.5% for low DL-RRS patients respectively in the external test cohort (HR: 3.89, 95% CI: 2.51–6.03, P < 0.001). Adjuvant chemotherapy was associated with improved RFS in Stage II patients with high DL-RRS (HR: 0.15, 95% CI: 0.06–0.38, P < 0.001). Conclusions: DL-RRS has a good predictive performance of 5-year recurrence risk in CRC, and will better serve the clinical decision-making. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to estimate the detection rates of adenomas and serrated polyps and to identify proximalization and associate risk factors in patients from Southern China. Methods: Consecutive patients undergoing colonoscopy from 2004 to 2013 in Guangzhou were included. The proportions of proximal adenomas to advanced adenomas and serrated polyps were compared and potential predictors were evaluated. Results: Colonoscopies ( n = 62,560) were performed, and 11,427 patients were diagnosed with polyps. Detection rates for adenomas, hyperplastic polyps, and serrated adenomas were 12.0, 2.5, and 0.2 patients per 100 colonoscopies. When comparing the 1st (2004-2008) to the 2nd period (2009-2013), adenoma and serrated polyp detection in proximal and distal colon both increased significantly (proximal colon [adenoma 3.9 vs. 6.1 patients/100 colonoscopies, P < 0.001; serrated polyp 0.4 vs. 1.1 patients/100 colonoscopies, P < 0.001]; distal colon [adenoma 6.6 vs. 7.2 patients/100 colonoscopies, P = 0.003; serrated polyp 1.2 vs. 2.4 patients/100 colonoscopies, P < 0.001]). Advanced adenoma detection increased over these two periods only in proximal colon (1st vs. 2nd period: 1.5 vs. 2.4 patients/100 colonoscopies, P < 0.001), not the distal colon ( P = 0.114). Multivariate analyses showed that diagnostic period was an independent predictor for adenoma proximalization (OR = 1.36, 95% CI 1.25-1.48, P < 0.001), but not for advanced adenomas ( P = 0.117) or serrated polyps ( P = 0.928). Conclusions: Adenomas and serrated polyps were increasingly detected throughout the colon, whereas advanced adenomas were only in proximal colon. A proximal shift tendency detected by colonoscopy was observed for adenomas, but not advanced adenomas or serrated polyps, in Southern China. The screening for proximal polyps should be emphasized and colonoscopy might be a preferred initial screening tool. [ABSTRACT FROM AUTHOR]

BACKGROUND . Use of upper gastrointestinal (UGI) series to diagnose UGI obstruction in neonates and infants has raised concern about increased radiation sensitivity of developing organs. OBJECTIVE . The purpose of this study was to assess the diagnostic performance of saline-aided ultrasound (US) in comparison with UGI series in evaluation for UGI obstruction in neonates and infants. METHODS . In this prospective multicenter study at three hospitals, inpatients were enrolled who were younger than 1 year and had suspected UGI obstruction between June 2015 and May 2018; patients with US evidence of malrotation or pyloric stenosis were ineligible. Enrolled patients underwent both saline-aided US (saline solution administered through a nasogastric tube) and UGI series. Surgical findings or at least 1-year of clinical follow-up findings served as the reference for presence of UGI obstruction. UGI obstruction was classified in terms of level (proximal vs distal) and cause. Two radiologists independently interpreted saline-aided US examinations to assess interobserver agreement and then reached consensus. Two other radiologists assessed upper GI series in consensus. Diagnostic performance for the presence and level of UGI obstruction was compared between modalities. Causes of obstruction were assessed with saline-aided US. RESULTS . A total of 209 neonates were included (116 boys, 93 girls; median age, 5 days; 124 (59.3%) patients had UGI obstruction (proximal in 108 patients). Saline-aided US had strong interobserver agreement for presence (κ = 0.87) and level (κ = 0.85) of obstruction. For presence of UGI obstruction, accuracy, sensitivity, and specificity were 94.7%, 98.4%, and 89.4% for saline-aided US and 89.5%, 95.2%, and 81.2% for UGI series. For obstruction level, accuracy, sensitivity, and specificity were 90.3%, 97.2%, and 56.3% for saline-aided US versus 87.1%, 92.6%, and 50.0% for UGI series. Accuracy for presence was significantly higher for saline-aided US ( p = .02); otherwise, these metrics were not different between tests ( p > .05). For causes of UGI obstruction (annular pancreas, duodenal web, duodenal atresia, and duodenal stenosis), the accuracy of saline-aided US ranged from 75.0% to 95.2%. CONCLUSION . Saline-aided US has high diagnostic performance for presence and level of UGI obstruction in neonates and infants, comparing favorably with UGI series. Saline-aided US may have additional utility in evaluating causes of obstruction. CLINICAL IMPACT . Saline-aided US may serve as an initial screening modality for UGI obstruction in neonates and infants. TRIAL REGISTRATION . Chinese Clinical Trial Registry ChiCTR-DCC-15006232.