Evaluation of microvessels in colorectal tumors by narrow band imaging magnification: including comparison with magnifying chromoendoscopy.

BACKGROUND/AIMS: Narrow band imaging (NBI) magnification analysis has entered use in clinical settings to diagnose colorectal tumors. Pit pattern analysis with magnifying endoscopy is already widely used to assess colorectal lesions and invasion depth. Our study compared diagnoses by vascular pattern analysis and pit pattern analysis with NBI magnification. METHODS: We examined 296 colorectal lesions-15 hyperplastic polyps (HP), 213 low-grade adenomas (L-Ad), 26 high-grade adenomas (H-Ad), 31 with intramucosal to scanty submucosal invasion (M-Sm-s), and 11 with massive submucosal invasion (Sm-m)-applying the system of Kudo et al. to analyze pit patterns, and the system of Tanaka et al. to analyze and classify vascular patterns by NBI into three categories: type A (hyperplasia pattern), type B (adenomatous pattern), and type C (carcinomatous pattern). Type C cases were subdivided into subtypes C1, C2, and C3. We used this system to examine histology type and invasion depth. RESULTS: Diagnostic sensitivity, specificity, and accuracy were 100% for both type II pit pattern HP and type A HP. Diagnostic sensitivity, specificity, and accuracy were 85.4, 94.5, and 93.2% for Vi and Vn pit pattern cancer and 95.2, 91.7, and 92.2% for type C cancer (no significant differences in sensitivity, specificity, or accuracy). Diagnostic sensitivity, specificity, and accuracy were comparable for Vi high-grade irregularity and Vn pit pattern Sm-m (90.9, 96.8, and 96.7%) and type C2/C3 Sm-m (90.1, 98.2, and 98.0%), with no significant differences in sensitivity, specificity, or accuracy. CONCLUSIONS: Vascular pattern analysis by NBI magnification proved comparable to pit pattern analysis.

Endoscopic submucosal dissection for colorectal neoplasia.

AIM: Endoscopic submucosal dissection (ESD) has been positively applied to and gradually standardized for early gastric cancer; however, it is not widely used in the colorectum because of its technical difficulty. METHODS: To increase the safety and ease of carrying out colon ESD, we developed a new scissors-type device that we call the stag beetle knife (SBK). Here we report on our efforts to assess the efficacy and safety of colon ESD using the SBK. RESULTS: ESD was carried out using SBK in 25 patients with colorectal neoplasia. All lesions were treated safety and easily, without any unexpected incisions. No delayed hemorrhage and perforation occurred. An en-bloc resection and a negative resection margin were obtained in all cases. CONCLUSION: ESD using the SBK can be carried out with greater ease and safety for colorectal neoplasia.

Successful endoscopic procedures for intraductal papillary neoplasm of the bile duct: a case report.

Attention has recently been focused on biliary papillary tumors as the novel disease entity intraductal papillary neoplasm of the bile duct (IPNB), which consists of papillary proliferation of dysplastic biliary epithelium. As even benign papillary tumors are considered as premalignant, some investigators recommend aggressive surgical therapy for IPNB, although no guidelines are available to manage this disease. Few reports have described long-term follow-up of patients with benign IPNB without radical resection. If patients with IPNB who are treated only with endoscopic procedures are noted, clinical profiles and alternative therapies other than resection may be recommended. We report the case of a patient who experienced repetitive cholangitis for 10 years and was finally diagnosed with IPNB. Radical resection could not be recommended because of the age of the patient, therefore, endoscopic sphincterotomy was performed. Although an endoscopic retrograde biliary drainage catheter was placed several times for repetitive cholangitis, the patient has done well during follow-up. Our case may offer insights into the natural course and management decisions for the novel disease entity of IPNB.

Endoscopic ultrasonography can diagnose distal biliary strictures without a mass on computed tomography.

AIM: To assess the diagnostic ability of endoscopic ultrasonography (EUS) for evaluating causes of distal biliary strictures shown on endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP), even without identifiable mass on computed tomography (CT). METHODS: The diagnostic ability of EUS was retrospectively analyzed and compared with that of routine cytology (RC) and tumor markers in 34 patients with distal biliary strictures detected by ERCP or MRCP at Dokkyo Medical School Hospital from December 2005 to December 2008, without any adjacent mass or eccentric thickening of the bile duct on CT that could cause biliary strictures. Findings considered as benign strictures on EUS included preservation of the normal sonographic layers of the bile duct wall, irrespective of the presence of a mass lesion. Other strictures were considered malignant. Final diagnosis of underlying diseases was made by pathological examination in 18 cases after surgical removal of the samples, and by clinical follow-up for > 10 mo in 16 cases. RESULTS: Seventeen patients (50%) were finally diagnosed with benign conditions, including 6 "normal" subjects, while 17 patients (50%) were diagnosed with malignant disease. In terms of diagnostic ability, EUS showed 94.1% sensitivity, 82.3% specificity, 84.2% positive predictive value, 93.3% negative predictive value (NPV) and 88.2% accuracy for identifying malignant and benign strictures. EUS was more sensitive than RC (94.1% vs 62.5%, P = 0.039). NPV was also better for EUS than for RC (93.3% vs 57.5%, P = 0.035). In addition, EUS provided significantly higher sensitivity than tumor markers using 100 U/mL as the cutoff level of carbohydrate antigen 19-9 (94.1% vs 53%, P = 0.017). On EUS, biliary stricture that was finally diagnosed as malignant showed as a hypoechoic, irregular mass, with obstruction of the biliary duct and invasion to surrounding tissues. CONCLUSION: EUS can diagnose biliary strictures caused by malignant tumors that are undetectable on CT. Earlier detection by EUS would provide more therapeutic options for patients with early-stage pancreaticobiliary cancer.

Endoscopic submucosal dissection in 100 lesions with early gastric carcinoma.

BACKGROUND/AIMS: ESD is a new diagnostic and treatment technique for early gastric cancer. This study aimed to evaluate the therapeutic effects observed at our department. METHODOLOGY: The subject group included 95 patients with 100 early-stage gastric cancers. According to the Gastric Cancer Treatment Guidelines published by the Japanease Gastric Cancer Association (JGCA) in 2001. Sixty-seven lesions presented a tumor measuring less than 20 mm and were concave (if not flat) without ulceration (specified indication of the guidelines of the Japanese Gastric Cancer Association), and 33 lesions were expanded indications. We then compared one-piece resection rates, en-bloc resection rates (one-piece resection that is lateral- and vertical-stump negative), curative en-bloc resection rates (en-bloc resection that fulfills the following three criteria: 1. differentiated adenocarcinoma; 2. no lymphtic or venous invasion, 3a. intramucosal cancer regardless of tumor size without ulceration, 3b. intramucosal cancer 30 mm in size with ulceration, 3c. minute submucosal cancer 30 mm in size). RESULTS: Among the specified indications and expanded indications, one-piece resection rates accounted for 97.0% and 75.8%, en-bloc resection rates for 83.6% and 60.6%, and curative en-bloc resection rates for 83.6% and 57.6%. The numbers of accident cases were three (postoperative hemorrhage; n = 1 perforation; n = 2) and four (postoperative hemorrhage; n = 1, perforation; n = 3), respectively. CONCLUSIONS: These studies indicated higher one-piece resection rates, en-bloc resection rates and curative en-bloc resection rates for lesions based on the guidelines than those based on the expanded guidelines.

A randomized prospective trial comparing unsedated endoscopy via transnasal and transoral routes using 5.5-mm video endoscopy.

We performed a randomized prospective trial to compare unsedated endoscopy via transnasal and transoral routes using a small-caliber endoscope. Two hundred patients referred for diagnostic esophagogastroduodenoscopy (EGD) were randomly allocated to two groups: those undergoing transnasal (TN) and transoral (TO) endoscopy. We examined the insertion rate, examination duration, nasal pain, pharyngeal pain, number of occurrences of pharyngeal reflex, severity of discomfort throughout the examination, and rate of adverse events. Patients were asked to rate the severity of their pain or discomfort on a 10-cm visual analog scale (VAS). We identified statistically significant differences between the TN and TO groups in rate of insertion (95% versus 100%, respectively, P < 0.05) and examination duration (9.7 +/- 3.0 min versus 8.4 +/- 2.7 min, respectively, P < 0.005). Severity of discomfort throughout the examination was comparable in the TN and TO groups (3.0 +/- 1.8 versus 2.9 +/- 2.3, NS). Nasal bleeding occurred as an adverse event in 4.1% of patients in the TN group. Patients in the TO group were more likely than those in the TN group to prefer the present method in the subsequent endoscopic examination (99.0% versus 82.1%, P < 0.00005). These results indicated that transoral insertion is superior to transnasal insertion in endoscopy procedures performed with small-caliber endoscope.

Glypican 4, a membrane binding protein for bactericidal/permeability-increasing protein signaling pathways in retinal pigment epithelial cells.

PURPOSE: Originally identified as a lipopolysaccharide binding protein with Gram-negative bactericidal activity in the leukocytes, bactericidal/permeability-increasing protein (BPI) has been shown to induce various effects in retinal cells in vivo and in vitro. METHODS: The authors recently reported that BPI can induce ERK1/2 and Akt activity and that it increases DNA synthesis in the bovine retinal pigment epithelial (RPE) and pericyte cells. The authors have extended the characterization of BPI interaction with membrane proteins from bovine RPE. Crude membrane pools from RPE were isolated, solubilized, and bound to rBPI(21) affinity column. Bound proteins were separated by SDS-PAGE and stained with Coomassie blue, which showed an intense band at 36 kDa consistently displaced by rBPI(21). RESULTS: Tandem mass spectrometry of the 36-kDa band suggested that cell surface protein glypican 4 (GPC4) serves as a putative BPI-binding protein. Heparitinase, phosphatidylinositol-specific phospholipase C, and anti-GPC4 antibody suppressed BPI-induced ERK and Akt phosphorylation in bovine RPE. Moreover, heparitinase also inhibited BPI actions on VEGF and PDGF-B mRNA expression induced by H(2)O(2). CONCLUSIONS: These new findings suggest that GPC4 is a specific binding protein for BPI on RPE to mediate the activation of ERK1/2, Akt, and the mRNA expressions of PDGF-B and VEGF.

[Prevalence and incidence of NSAID-induced gastrointestinal ulcers and bleeding].

Helicobacter pylori infection and non-steroidal anti-inflammatory drugs (NSAID) have been accepted as major causes of upper gastrointestinal (GI) ulcers and bleeding. As patients with Helicobacter pylori infection have decreased, upper GI disorders related to NSAID have been relatively increasing. Among patients taking low-dose aspirin, the prevalence of upper GI ulcers is 10-40% and aspirin increases the risk of upper GI bleeding up to 2-fold. Among patients taking nonaspirin NSAID, the prevalence of upper GI ulcers is around 20% and nonaspirin NSAID increases the risk of upper GI bleeding up to 4- to 6-fold. Since the prevalence of GI disorders related to NSAID is very high, endoscopic examination might be considered to monitor GI lesions for patients taking NSAID.

[Guideline for prophylaxis and treatment of NSAID-associated gastric ulcerations].

Both Helicobacter pylori (H. pylori) infection and non-steroidal anti-inflammatory drug (NSAID) administration independently and significantly increase the risk of peptic ulceration and ulcer bleeding as its complication. Because of increasing ratio of the senior generation in Japan, the relative role of NSAID including low-dose aspirin as an anti-platelet therapy, will be more important in the pathogenesis of peptic ulcerations. In order to prevent peptic ulcerations, one of the major adverse events of NSAID, a series of selective COX-2 inhibitors has been developed and some of them have been widely used clinically. However, long-term use of a COX-2 inhibitor may be associated with higher risk of cardiovascular events and strokes. Herein, we focus on prophylaxis and treatment of NSAID-associated gastric ulcerations.

[Role of Helicobacter pylori eradication in the prevention of peptic ulcer in NSAID users].

Helicobacter pylori (H. pylori) and non-steroidal anti-inflammatory drug (NSAID) are independent risk factors for peptic ulcers and ulcer complications and they have additive or synergistic effects. A meta-analysis showed that the OR for the incidence of peptic ulcer was 61.1 in patients infected with H. pylori and also taking NSAID when compared to patients uninfected with H. pylori and not taking NSAID. H. pylori eradication may prevent NSAID-induced ulcers in NSAID naive patients. In patients receiving long-term NSAID, proton pump inhibitor(PPI) is more effective in the prevention of ulcer recurrence and bleeding. However, H. pylori eradication should be considered in patients receiving long -term PPI maintenance treatment to prevent the development of corpus gastritis and gastric atrophy.

Up-regulation of TFF1 (pS2) expression by TNF-alpha in gastric epithelial cells.

BACKGROUND AND AIM: TFF1 (pS2) is expressed at a high level in gastric epithelial cells and plays an important role in protecting the gastric mucosa. However, the regulatory mechanisms of TFF1 expression are not fully understood. The aim of this study was to investigate the effect of TNF-alpha, a representative proinflammatory cytokine, on TFF1 expression. METHODS: MKN45 and AGS cells, derived from human gastric carcinoma, were used. Endogenous TFF1 mRNA expression was analyzed by real-time quantitative RT-PCR. The sequences of the human TFF1 promoter were cloned into the pGL3-basic vector and reporter gene assays were performed. Nuclear factor (NF)-kappaB activity was monitored using a reporter vector that contained multiple copies of NF-kappaB responsive element upstream of the luciferase gene. Interaction between NF-kappaB and TFF1 cis-element was examined by electophoretic mobility shift assay (EMSA). RESULTS: TNF-alpha activated NF-kappaB and up-regulated endogenous TFF1 mRNA expression as well as the transcription of the TFF1 reporter genes in a dose-dependent manner. IL-1beta, another proinflammatory cytokine, also up-regulated TFF1 expression. TNF-alpha responsive element was mapped between -342 and -147 of the human TFF1 promoter and a putative NF-kappaB binding site was identified at -231. When this element was deleted, the reporter genes became almost insensitive to TNF-alpha treatment. EMSA showed binding of NF-kappaB to this element. CONCLUSIONS: Inflammatory stimuli that activate NF-kappaB appear to up-regulate TFF1 expression in gastric epithelial cells. This mechanism may aid in the protection of the gastric mucosa under inflammatory conditions.

Peroxisome proliferator-activated receptor gamma (PPARgamma) regulates trefoil factor family 2 (TFF2) expression in gastric epithelial cells.

Although trefoil factor family 2 (TFF2) plays a critical role in the defense and repair of gastric mucosa, the regulatory mechanism of TFF2 expression is not fully understood. In this study, we investigated the regulation of TFF2 expression by peroxisome proliferator-activated receptor gamma (PPARgamma) in gastric epithelial cells. MKN45 gastric cells were used. TFF2 mRNA expression was analyzed by real-time quantitative RT-PCR. The promoter sequence of the human TFF2 gene was cloned into pGL3-basic vector for reporter gene assays. Ciglitazone was mainly used as a specific PPARgamma ligand. MKN45 cells expressed functional PPARgamma proteins. Endogenous TFF2 mRNA expression and TFF2 reporter gene transcription was significantly up-regulated by ciglitazone in a dose-dependent manner. Reporter gene assays showed that two distinct cis-elements are involved in the response to PAPRgamma activation. Within one of these element (nucleotides -558 to -507), we identified a functional peroxisome proliferator responsive element (PPRE) at -522 (5'-GGGACAAAGGGCA-3'). Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay confirmed the binding of PPARgamma to this sequence. Another element (nucleotides -407 to -358) appeared to be a composite enhancer element indirectly regulated by PPARgamma and a combination of these two cis-elements was required for the full response of the human TFF2 gene expression to PPARgamma. These data demonstrate that human TFF2 gene is a direct target of PPARgamma in gastric epithelial cells. Since TFF2 is a critical gastroprotective agent, PPARgamma may be involved in the gastric mucosal defense through regulating TFF2 expression in humans.

Regulation of TFF3 expression by homeodomain protein CDX2.

Although trefoil factor family 3 (TFF3) plays an important role in protecting the intestinal mucosa, the regulatory mechanisms of its expression are not fully understood. Since homeodomain protein CDX2 has been reported to be critically involved in the development and differentiation of intestinal epithelium, we examined whether CDX2 affects the expression of TFF3. The transcription of human TFF3 reporter genes was significantly up-regulated by the transient overexpression of CDX2 in COS-7 cells and AGS gastric cells. Electrophoretic mobility shift assay revealed the presence of at least two CDX-binding sites within the human TFF3 promoter. Deletion analysis showed the relative importance of the proximal CDX-binding site at -63. We also detected the up-regulation of endogenous TFF3 mRNA expression in AGS cells stably transfected with CDX2 expression vectors. These results suggest that CDX2 plays a key role in the expression of TFF3 in the intestine and perhaps in intestinal metaplasia of the stomach.

Bactericidal/permeability-increasing protein's signaling pathways and its retinal trophic and anti-angiogenic effects.

Bactericidal/permeability-increasing protein (BPI) was originally identified as a lipopolysaccharide (LPS) binding protein with gram-negative bactericidal activity in the leukocytes. In this study, we characterized the previously unknown effects of BPI in the eye and the molecular mechanisms involved in its action. BPI mRNA was detected in bovine retina; retinal pigment epithelium; and primary cultures of bovine retinal pigment epithelial cells (RPE), pericytes (RPC), and endothelial cells (REC); while BPI protein was measured in human vitreous and plasma. BPI, but not control protein thaumatin, activated extracellular regulated kinase (ERK) and AKT, and increased DNA synthesis in RPE and RPC but not in REC. A human recombinant 21 kDa modified amino-terminal fragment of BPI (rBPI21) reduced H2O2-induced apoptosis in RPE and inhibited vascular endothelial growth factor (VEGF)-stimulated ERK phosphorylation in REC when preincubated with VEGF. Intraperitoneal (i.p.)-injected rBPI21 reduced ischemia-induced retinal neovascularization and diabetes-induced retinal permeability. Since BPI has unusual dual properties of promoting RPC and RPE growth while suppressing VEGF-induced REC growth and vascular permeability, the mechanistic understanding of BPI's action may provide novel therapeutic opportunities for diabetic retinopathy and age-related macular degeneration.

"Duodenal intussusception" due to adenoma of the papilla of Vater.

The case of a 55-year-old woman with a pedunculate adenoma of the papilla of Vater is presented. Diagnostic imaging modalities including ultrasonography, CT scan, magnetic resonance of cholangiopancreatography, simultaneous duodenography and cholangiography, and angiography showed a giant tumor protruding intraluminally and moving forward in the duodenum by peristalsis. It had a duodenal intussusception-like appearance, with remarkable left-lower deviation of the common bile duct and major pancreatic duct in the papilla of Vater as far as the left side of the aorta. Episodes of jaundice or ileus were absent, probably because the tumor was mobile in the duodenum. As biopsy specimens showed no malignancy and intraductal ultrasonography in the common bile duct revealed no intraductal invasion of the tumor in the papilla of Vater, the patient underwent transduodenal papillectomy with papilloplasty with pancreatic ductoplasty. Pathological diagnosis of consecutive specimens was a papillary adenoma with moderate atypia and occasional tubular structure. There seems to be an exceptional subtype of the tumor in the papilla of Vater, like this case, demonstrating the duodenal intussusception-like appearance without prominent clinical symptoms.

Cyclins and cyclin-dependent kinases: comparative study of hepatocellular carcinoma versus cirrhosis.

Increasing evidence has indicated that perturbation of cyclins is one of the major factors leading to cancer. The aim of this study was not only to investigate various cell cycle-related kinase activities in hepatocellular carcinoma (HCC), but also to analyze the difference of cell cycle-related kinase activity levels between hepatitis C virus (HCV)-induced HCC and HCV-induced cirrhosis. The protein levels of cyclins D1, E, A, and H, and of cyclin dependent kinase 1 (Cdk1), Cdk2, Cdk4, Cdk6, and Cdk7 in HCC and in surrounding nontumorous cirrhosis were determined by Western blot. The enzymatic activities of cyclins D1, E, A, Cdk1, Cdk4, Cdk6, Cdk7, and Wee1 were measured using in vitro kinase assays. Protein levels and kinase activities of cyclin D1, Cdk4, cyclin E, cyclin A, and Wee1 were significantly elevated in HCC compared with surrounding cirrhotic tissues. The enhanced cyclin D1-related kinase activity in HCC was accompanied by the up-regulation of Cdk4 activity, but not Cdk6 activity. The kinase activities of Cdk6, Cdk7, and Cdk1 did not differ between HCC and surrounding cirrhotic tissues. In addition, the protein levels and kinase activities of cyclin D1, Cdk4, and cyclin E were higher in poorly differentiated HCC and advanced HCC. In conclusion, the increases of cyclin D1, Cdk4, cyclin E, cyclin A, and Wee1 play an important role in the development of HCC from cirrhosis. Cyclin D1, Cdk4, and cyclin E activation may be closely related to the histopathologic grade and progression of HCC.