Toshiaki Gunji

Circulating Exosomal microRNAs as Biomarkers of Colon Cancer

Purpose Exosomal microRNAs (miRNAs) have been attracting major interest as potential diagnostic biomarkers of cancer. The aim of this study was to characterize the miRNA profiles of serum exosomes and to identify those that are altered in colorectal cancer (CRC). To evaluate their use as diagnostic biomarkers, the relationship between specific exosomal miRNA levels and pathological changes of patients, including disease stage and tumor resection, was examined. Experimental Design Microarray analyses of miRNAs in exosome-enriched fractions of serum samples from 88 primary CRC patients and 11 healthy controls were performed. The expression levels of miRNAs in the culture medium of five colon cancer cell lines were also compared with those in the culture medium of a normal colon-derived cell line. The expression profiles of miRNAs that were differentially expressed between CRC and control sample sets were verified using 29 paired samples from post-tumor resection patients. The sensitivities of selected miRNAs as biomarkers of CRC were evaluated and compared with those of known tumor markers (CA19-9 and CEA) using a receiver operating characteristic analysis. The expression levels of selected miRNAs were also validated by quantitative real-time RT-PCR analyses of an independent set of 13 CRC patients. Results The serum exosomal levels of seven miRNAs (let-7a, miR-1229, miR-1246, miR-150, miR-21, miR-223, and miR-23a) were significantly higher in primary CRC patients, even those with early stage disease, than in healthy controls, and were significantly down-regulated after surgical resection of tumors. These miRNAs were also secreted at significantly higher levels by colon cancer cell lines than by a normal colon-derived cell line. The high sensitivities of the seven selected exosomal miRNAs were confirmed by a receiver operating characteristic analysis. Conclusion Exosomal miRNA signatures appear to mirror pathological changes of CRC patients and several miRNAs are promising biomarkers for non-invasive diagnosis of the disease.

Endoscopic tissue shielding method with polyglycolic acid sheets and fibrin glue to cover wounds after colorectal endoscopic submucosal dissection (with video).

BACKGROUNDnColorectal endoscopic submucosal dissection (ESD) has made it possible to resect large specimens in an en bloc fashion. However, this can lead to postoperative adverse events, such as perforation and bleeding. Prevention of adverse events after colorectal ESD is therefore an important goal.nnnOBJECTIVEnTo evaluate the utility of a shielding method using polyglycolic acid (PGA) sheets and fibrin glue to manage ulcers after colorectal ESD.nnnDESIGNnProspective, single-arm, pilot study.nnnSETTINGnSingle tertiary care center for colorectal ESD in Japan.nnnPATIENTSnTen patients with 10 colorectal tumors scheduled for ESD were enrolled between September and November 2012.nnnINTERVENTIONSnJust after ESD, we placed PGA sheets on the mucosal defect with biopsy forceps. After the whole defect was covered, we sprayed fibrin glue through a special double-lumen spraying tube. We sprayed fibrinogen through 1 lumen and then thrombin through the other lumen.nnnMAIN OUTCOME MEASUREMENTSnSuccess rate, mean procedure time, and adverse events associated with the covering technique and the persistence of PGA sheets at follow-up colonoscopy.nnnRESULTSnAll 10 tumors were successfully resected. Mean tumor size was 39.7 ± 15.2 mm. All mucosal defects were successfully covered with PGA sheets. Mean procedure time was 18.7 ± 15.9 minutes. No procedure-related adverse events occurred. Upon colonoscopy 9 to 12 days after ESD, the PGA sheets were still fixed on the whole defect in 8 patients.nnnLIMITATIONSnSmall sample size.nnnCONCLUSIONSnOur technique, which uses PGA sheets and fibrin glue, appears to shield mucosal defects, and it may be effective in reducing postoperative adverse events.

An effective training system for endoscopic submucosal dissection of gastric neoplasm.

BACKGROUND AND STUDY AIMSnA standard training system for endoscopic submucosal dissection (ESD) remains to be established. In this study, we evaluated the validity of our training program for gastric ESD.nnnPATIENTS AND METHODSnFour trainees performed gastric ESD for a total of 117 lesions in 107 patients (27 to 30 consecutive lesions per trainee) at a tertiary referral center during 2 years in the training program. Trainees, who already had the fundamental skills and knowledge needed for ESD, each assisted at 40 gastric ESD procedures, then in 20 cases applied post-ESD coagulation (PEC) to gastric mucosal defects; they then began to perform ESD, starting with gastric antral lesions. Treatment outcomes, including mean procedure time, and rates of en bloc resection, en bloc plus R0 resections, complications, and self-completion, were evaluated, for the initial 15 and subsequent 12 to 15 cases.nnnRESULTSnOverall rates of en bloc resection and en bloc plus R0 resection were as high as 100 % and 96.6 %, respectively. Regarding complications, seven cases of delayed hemorrhage (6.0 %) and three cases of perforation (2.6 %) occurred; all complications were solved endoscopically. The most frequent reason for operator change was lack of submucosal dissection skill. The self-completion rate was more than 80 % even in the early period, and did not increase for later cases.nnnCONCLUSIONSnOur training system enabled novice operators to perform gastric ESD without a decline in clinical outcomes. Key features of this training are prior intensive learning and actual ESD during the learning period under expert supervision.

Magnifying endoscopy with narrow-band imaging helps determine the management of gastric adenomas

BackgroundThere are no clear clinical criteria for the management of gastric lesions diagnosed as adenomas (Vienna classification category 3) by pre-treatment biopsy. In the present study, we examined the feasibility of magnifying endoscopy with narrow-band imaging (ME–NBI) in discriminating early gastric cancers (Vienna classification category 4 or 5) from adenomas in lesions diagnosed as adenomas by pre-treatment biopsy.MethodsThis was a single-center cross-sectional retrospective study at a tertiary referral center. One hundred thirty-seven consecutive cases of gastric lesions diagnosed as adenomas in pre-treatment forceps biopsy were examined with conventional non-magnifying endoscopy under white light, non-magnifying chromoendoscopy, and ME–NBI. We investigated the association between the final pathological diagnoses (carcinoma or adenoma) and the following factors: lesion size (mm), color (red or white), macroscopic type (depressed or others), presence of ulceration, and positive ME–NBI finding. The presence of an irregular microvascular pattern or an irregular microsurface pattern with a demarcation line between the lesion and the surrounding area was regarded as a positive ME–NBI finding.ResultsLesion size was significantly larger in carcinomas than adenomas (Pxa0=xa00.005). Depressed lesion (Pxa0=xa00.011), red color (Pxa0<xa00.001), and positive ME–NBI finding (Pxa0<xa00.001) were significant predictive factors for carcinoma. Multivariate logistic regression confirmed that red color (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.26–7.34, Pxa0=xa00.14) and a positive ME–NBI finding (OR 13.68, 95% CI 5.69–32.88, Pxa0<xa00.001) were independent predictive factors for carcinomas. A positive ME–NBI finding was the strongest predictive factor.ConclusionsME–NBI is useful in planning the management of lesions diagnosed as adenomas by pre-treatment forceps biopsy.

The waist circumference-adjusted associations between hyperuricemia and other lifestyle-related diseases

BackgroundFew studies have assessed the associations between hyperuricemia and lifestyle-related diseases after adjusting for waist circumference (WC) and sex.MethodsThis cross-sectional study included 33,498 Japanese individuals, and was conducted at the Center for Preventive Medicine, NTT Kanto Medical Center, Tokyo, from May 2006 to March 2015. Hyperuricemia was defined as a uric acid level ofxa0>7xa0mg/dl in men;xa0>6xa0mg/dl in women. Metabolic syndrome (Mets) components were defined using the Japanese criteria for Mets. The subjects were stratified into quartiles according to their WC as follows: males:xa0<78.4, 78.4 to <83.5, 83.5 toxa0<89, andxa0≥89xa0cm; females:xa0<71.6, 71.6 to <77, 77 to <83.2, andxa0≥83.2xa0cm. The relationships between these quartiles and the presence ofxa0≥2 components of Mets or hyperuricemia were then evaluated using Chi square analysis. The presence ofxa0≥2 components of Mets were then determined using multivariate logistic regression analysis adjusting for age, the presence of hyperuricemia, WC, and lifestyle habits.ResultsHyperuricemia was found to be an independent predictor of lifestyle-related diseases after adjusting for age, WC, and lifestyle in both sexes. Males: a uric acid level ofxa0>7xa0mg/dl (odds ratio [OR]: 1.70, 95% confidence interval [CI]: 1.57–1.83), Females: a uric acid level ofxa0>6xa0mg/dl (OR: 2.35, 95% CI 1.83–2.99).ConclusionHyperuricemia was found to be an independent predictor of several lifestyle-related diseases, even after adjusting for WC which is closely related with insulin resistance. Hyperuricemia might require greater attention during the prevention of lifestyle-related diseases and future cardiovascular disease.

Serum TFF1 and TFF3 but not TFF2 are higher in women with breast cancer than in women without breast cancer

Breast cancer remains a common malignancy in women, but the take-up for breast cancer screening programs in Japan is still low, possibly due to its perceived inconvenience. TFF1 and TFF3 are expressed in both breast cancer tissue and normal breast. Serum trefoil proteins were reported as cancer screening markers for gastric, prostate, lung, pancreatic cancer and cholangio carcinoma. The purpose of this study was to examine whether serum trefoil proteins could be screening biomarkers for breast cancer. Serum trefoil proteins in 94 breast cancer patients and 84 health check females were measured by ELISA. Serum TFF1 and TFF3 were significantly higher and serum TFF2 was significantly lower in breast cancer patients. Area under the curve of receiver operating characteristic of TFF1, TFF2, and TFF3 was 0.69, 0.83, and. 0.72, respectively. AUC of the combination of TFF1, TFF2, and TFF3 was 0.96. Immunohistochemically, TFF1 expression was positive in 56.5% and TFF3 was positive in 73.9% of breast cancers, while TFF2 was negative in all tumors. Serum TFF1 had positive correlation with expression of TFF1 in breast cancer tissue. Serum concentrations of TFF1 and TFF3 but not TFF2 are higher in women with breast cancer than in women without breast cancer.

The Relationships between Metabolic Disorders (Hypertension, Dyslipidemia, and Impaired Glucose Tolerance) and Computed Tomography-Based Indices of Hepatic Steatosis or Visceral Fat Accumulation in Middle-Aged Japanese Men.

Background Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA. Methods The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm2 at the level of the navel. Metabolic disorders were defined using Japan’s metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups. Results Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01). Conclusions It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are needed to reveal the relationships between the components of metabolic disorders and HS/VFA.

Utility of 75-g oral glucose tolerance test results and hemoglobin a1c values for predicting the incidence of diabetes mellitus among middle-aged Japanese men -a large-scale retrospective cohort study performed at a single hospital.

OBJECTIVEnThe aim of this study was to investigate the associations between the incidence of diabetes and the accumulation of markers of impaired glucose metabolism; i.e., pre-diabetes.nnnMETHODSnThis retrospective cohort study recruited 1,631 men without diabetes at baseline who attended more than two routine health check-ups at our institution between 2006 and 2012. The participants were divided into four groups based on the number of markers of impaired glucose metabolism exhibited at the initial examination. The following markers of impaired glucose metabolism were defined as risk factors for diabetes: a fasting plasma glucose level of ≥110 mg/dL, 2-hour plasma glucose level of ≥140 mg/dL and glycated hemoglobin (HbA1c) value of ≥6.0% (42 mmol/moL). The risk of developing diabetes was assessed using a multivariate analysis.nnnRESULTSnThe median examination interval was 1,092 days. The incidence of diabetes rose in association with the number of markers. The subjects with two markers displayed a multivariate-adjusted odds ratio (OR) for diabetes of 19.43 [95% confidence interval (CI): 9.70-38.97] and the subjects with three markers displayed an OR of 48.30 (95% CI: 20.39-115.85) compared with the subjects with one or no markers.nnnCONCLUSIONnThe present results demonstrate the impact of accumulating markers of impaired glucose metabolism on the risk of developing diabetes. Anti-diabetes intervention strategies should aim to comprehensively assess an individuals risk of developing diabetes at the pre-diabetes stage.

Antithrombotic drug does not affect the positive predictive value of an immunochemical fecal occult blood test

Antithrombotic drugs may affect the diagnostic performance of immunochemical fecal occult blood test (iFOBT) for colorectal cancer (CRC) screening. The aim of the present study was to assess the effect of antithrombotic drugs on the diagnostic performance of iFOBT.