Pancreatic cancer is associated with an extremely poor prognosis, so new biomarkers that can detect the initial stages are urgently needed. The significance of serum microRNA (miR) levels in pancreatic neoplasm such as pancreatic cancer and intraductal papillary mucinous neoplasm (IPMN) diagnosis remains unclear. We herein evaluated the usefulness of miRs enclosed in serum exosomes (ExmiRs) as diagnostic markers. The ExmiRs from patients with pancreatic cancer (n = 32) or IPMN (n = 29), and patients without neoplasms (controls; n = 22) were enriched using ExoQuick-TC™. The expression of ExmiRs was evaluated using a next-generation sequencing analysis, and the selected three miRs through this analysis were confirmed by a quantitative real-time polymerase chain reaction. The expression of ExmiR-191, ExmiR-21 and ExmiR-451a was significantly up-regulated in patients with pancreatic cancer and IPMN compared to the controls (p < 0.05). A receiver operating characteristic curve analysis showed that the area under the curve and the diagnostic accuracy of ExmiRs were 5–20% superior to those of three serum bulky circulating miRs (e.g.; ExmiR-21: AUC 0.826, accuracy 80.8%. Circulating miR-21: AUC 0.653, accuracy 62.3%). In addition, high ExmiR-451a was associated with mural nodules in IPMN (p = 0.010), and high ExmiR-21 was identified as a candidate prognostic factor for the overall survival (p = 0.011, HR 4.071, median OS of high-ExmiR-21: 344 days, median OS of low-ExmiR-21: 846 days) and chemo-resistant markers (p = 0.022). The level of three ExmiRs can thus serve as early diagnostic and progression markers of pancreatic cancer and IPMN, and considered more useful markers than the circulating miRs (limited to these three miRs).

Backgrounds. The efficacy of clipping for preventing the delayed bleeding after the removal of colon polyps is still controversial. In order to clarify this efficacy, a randomized controlled study was performed.Methods. One hundred and fifty-six patients with colon neoplasms (288 lesions) were enrolled in the study. The patients were randomly divided into two groups: clipping or nonclipping groups using a sealed envelope method before the endoscopic resections. Eight specialists and nine residents were invited to perform this procedure. The risk factors and the rates of delayed bleeding after the endoscopic resections in each group were investigated.Results. There were no significant differences in the bleeding rate between the clipping and nonclipping groups, while the length of the procedure was significantly longer and the cost was higher in the clipping group than in the nonclipping group. The rate of bleeding was significantly higher in cases with polyps 2 cm or larger and with a longer procedure time, while none of the other factors affected the bleeding rate.Conclusions. This randomized controlled study revealed no significant effect of prophylactic clipping for preventing delayed bleeding after the endoscopic resection of colon polyps.

We compared the diagnostic accuracy of the fecal calprotectin (FCP) test vs the fecal immunochemical blood test (FIT) in determining the endoscopic severity and predicting outcomes of patients with ulcerative colitis (UC). We performed a nationwide study of 879 patients with UC, enrolled at medical centers across Japan, from March 2015 to March 2017. We collected data on fecal biomarkers, endoscopic severities, and other clinical indices from Cohort 1 (n = 427) and assessed the diagnostic accuracy of FCP measurement and FIT results in determining clinical severity, based on Mayo score, and endoscopic remission, based on Mayo endoscopic sub-score (MES) or UC endoscopic index of severity. We also followed 452 patients in clinical remission from UC (Cohort 2) for 12 months and evaluated the associations of FCP levels and FIT results with clinical recurrence. The levels of FCP and FIT each correlated with the MES and UC endoscopic index of severity. There were no significant differences in the areas under the curve of FCP vs FIT in distinguishing patients with MES≤1 from those with MES≥2 (P = .394) or in distinguishing patients with MES=0 from those with MES≥1 (P = .178). Among 405 patients in clinical remission at baseline, 38 (9.4%) had UC recurrences within 3 months and 90 (22.2%) had recurrences within 12 months. FCP≥146 mg/kg (hazard ratio [HR], 4.83; 95% confidence interval [CI], 2.80-8.33) and FIT≥77 ng/mL (HR, 2.92; 95% CI, 1.76-4.83) were independently associated with clinical recurrence within 12 months. UC recurred within 12 months in 69% of patients with levels of FCP≥146 mg/kg and FIT ≥77 ng/mL; this value was significantly higher than the rate of recurrence in patients with levels of FCP≥146 mg/kg and FIT <77 ng/mL (31.5%, P < .001) or patients with levels of FCP<146 mg/kg and FIT ≥77 ng/mL (30.0%, P < .001). In a nationwide study of patients with UC in Japan, we found that the level of FCP and FIT could each identify patients with endoscopic markers of disease severity (MES≥2). The combination of FCP and FIT results can identify patients in remission who are at risk for disease recurrence. Clinical Trials Registry no: UMIN000017650 (http://www.umin.ac.jp/ctr/).

Background: Some patients under close colonoscopic surveillance still develop colorectal cancer, thus suggesting the overlook of colorectal adenoma by endoscopists. AFI detects colorectal adenoma as a clear magenta, therefore the efficacy of AFI is expected to improve the detection ability of colorectal adenoma. The aim of this study is to determine the efficacy of AFI in detecting colorectal adenoma. Methods: This study enrolled 88 patients who underwent colonoscopy at Asahikawa Medical University and Kushiro Medical Association Hospital. A randomly selected colonoscopist first observed the sigmoid colon and rectum with conventional high resolution endosopy (HRE). Then the colonoscopist changed the mode to AFI and handed to the scope to another colonoscopist who knew no information about the HRE. Then the second colonoscopist observed the sigmoid colon and rectum. Each colonoscopist separately recorded the findings. The detection rate, miss rate and procedural time were assessed in prospective manner. Results: The detection rate of flat and depressed adenoma, but not elevated adenoma, by AFI is significantly higher than that by HRE. In less-experienced endoscopists, AFI dramatically increased the detection rate (30.3%) and reduced miss rate (0%) of colorectal adenoma in comparison to those of HRE (7.7%, 50.0%), but not for experienced endoscopists. The procedural time of HRE was significantly shorter than that of AFI. Conclusions: AFI increased the detection rate and reduced the miss rate of flat and depressed adenomas. These advantages of AFI were limited to less-experienced endoscopists because experienced endoscopists exhibited a substantially high detection rate for colorectal adenoma with HRE.

The oncogenic properties of heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1) have been reported, although the tumor-promoting mechanism remains unclear. We herein report the mechanism underlying colorectal cancer cell progression mediated by hnRNP H1. The growth of colorectal cancer cells was suppressed by hnRNP H1 downregulation. A terminal deoxynucleotidyl transferase dUTP nick-end labeling assay revealed the anti-apoptotic effect of hnRNP H1 in colorectal cancer cells. An RNA immunoprecipitation assay revealed that hnRNP H1 bound to sphingosine-1-phosphate lyase 1 (SGPL1). Reverse transcription-polymerase chain reaction revealed the high expression of hnRNP H1 mRNA in colorectal cancer cells and Spearman’s rank correlation coefficient showed a strong positive correlation between hnRNP H1 mRNA and SGPL1 mRNA. An siRNA of hnRNP H1 decreased SGPL1 mRNA expression in colorectal cancer cells, but not in non-tumorous cells. These findings suggested that hnRNP H1 increased SGPL1 mRNA expression specifically in cancer cells through direct binding. Targeted knockdown of hnRNP H1 or SGPL1 with siRNAs upregulated p53 phosphorylation and p53-associated molecules, resulting in cell growth inhibition, while hnRNP H1 upregulated the mRNA of SGPL1 and inhibited p53 activation, thereby promoting tumor cell growth. This is a novel mechanism underlying colorectal cancer cell progression mediated by hnRNP H1–SGPL1 mRNA stabilization.

Previous investigations have indicated that RNA-binding proteins (RBPs) are key molecules for the development of organs, differentiation, cell growth and apoptosis in cancer cells as well as normal cells. A bioinformatics analysis based on the mRNA expression and a somatic mutational database revealed the association between aberrant expression/mutations of RBPs and cancer progression. However, this method failed to detect functional alterations in RBPs without changes in the expression, thus leading to false negatives. To identify major tumor-associated RBPs, we constructed an siRNA library based on the database of RBPs and assessed the influence on the growth of colorectal, pancreatic and esophageal cancer cells. A comprehensive analysis of siRNA functional screening findings using 1198 siRNAs targeting 416 RBPs identified 41 RBPs in which 50% inhibition of cell growth was observed in cancer cells. Among these RBPs, 12 showed no change in the mRNA expression and no growth suppression in non-cancerous cells when downregulated by specific siRNAs. We herein report for the first time cancer-promotive RBPs identified by a novel functional assessment using an siRNA library of RBPs combined with expressional and mutational analyses.