C-terminal-truncated HBV X promotes hepato-oncogenesis through inhibition of tumor-suppressive β-catenin/BAMBI signaling

C-terminal-truncated hepatitis B virus (HBV) X (HBx) (ctHBX) is frequently detected in hepatocellular carcinoma (HCC) through HBV integration into the host genome. However, the molecular mechanisms underlying ctHBx-associated oncogenic signaling have not yet been clarified. To elucidate the biological role of ctHBx in hepato-oncogenesis, we functionally analyzed ctHBx-mediated regulation of the activin membrane-bound inhibitor bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) through transforming growth factor-β (TGF-β) or β-catenin (CTNNB1) in HCC cells and in an animal model, and we compared its role to that of the full-length HBx protein. Ectopic ctHBx expression generated more colonies in anchorage-dependent and -independent growth assays than did HBx expression alone. ctHBx downregulated BAMBI to a greater degree than did HBx in HCC cells. HBx activated the Wnt/β-catenin pathway, which positively regulated the BAMBI expression through T-cell factor 1 signaling, whereas ctHBx negatively regulated the Wnt/β-catenin pathway. BAMBI downregulated the β-catenin and TGF-β1 signaling pathways. TGF-β1 positively regulated BAMBI expression thorough Smad3 signaling. Furthermore, knockdown of BAMBI was more tumorigenic in HCC cells. Therefore, downregulation of both β-catenin and TGF-β1 signaling by BAMBI might contribute to tumor suppression in mice xenotransplanted with HepG2 or SH-J1 cells. Taken together, ctHBx may have a more oncogenic role than HBx through its inhibition of tumor-suppressive β-catenin/BAMBI signaling.

Disease Progression in Chronic Hepatitis B Patients under Long-Term Antiviral Therapy

BACKGROUND/AIMS: We investigated factors associated with the disease progression and development of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients during long-term oral nucleos(t)ide analog (NA) therapy. METHODS: This retrospective study included 524 naive CHB patients who received oral NA therapy for more than 48 weeks between January 2003 and December 2007. The primary outcome was 5-year cumulative probability of disease progression and HCC development. Disease progression was defined as cirrhosis development, cirrhotic complications, HCC or liver-related mortality. RESULTS: For the 524 patients, the cumulative probabilities of disease progression and HCC development at 1, 2, 3, 4 and 5 years were 1.1%, 6.3%, 9.0%, 11.6%, and 16.2% and 0.2%, 1.8%, 3.6%, 5.8%, and 9.3%, respectively. In multivariate analysis, age >50 years (hazard ratio [HR], 1.05) and cirrhosis (HR, 2.95) were significant factors for disease progression. Similarly, age >50 years (HR, 1.05), family history of HCC (HR, 5.48), and cirrhosis (HR, 17.16) were significant factors for HCC development. Importantly, longer duration (>12 months) of maintained virological response (<20 IU/mL) reduced the risks of disease progression (HR, 0.19) and HCC development (HR, 0.09). CONCLUSIONS: Longer duration of maintained virological response significantly reduces the risk of disease progression or HCC development in CHB patients undergoing long-term oral NA therapy.

Oncologist Perspectives on Rare Cancer Care: A Nationwide Survey / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In response to the challenges and difficulties imposed by rare cancers, multi-stakeholder initiatives dedicated to improving rare cancer care was launched, and several recommendations were made by professional societies. However, these primarily reflect the view of the advocates and supporters, and may not represent the views of the "average" clinician or researcher. In this study, we sought to investigate perceived difficulties with regard to rare cancer care and potential solutions endorsed by oncologists. MATERIALS AND METHODS: A representative sample of 420 oncologists recruited in 13 cancer centers participated in a nationwide survey. RESULTS: Oncologists faced various difficulties in treatment of patients with rare cancers, including the lack of clinical practice guidelines (65.7%) and personal experience (65.2%), lack of approved treatment options (39.8%), and reimbursement issues (44.5%). They were generally supportive of recent recommendations by multi-stakeholder initiatives as well as professional societies for development of clear clinical practice guidelines (66.0%), flexible reimbursement guidelines (52.9%), and a national rare cancer registry (47.4%). However, there was only moderate endorsement for referrals to high-volume centers (35.5%) and encouragement of off-label treatments (21.0%). CONCLUSION: Insights into the general attitudes of oncologists gained through our nationwide survey of representative samples would be helpful in development of clinical practices and public health policies in rare cancer treatment and research.

Growth Factor-mediated Tumor Progression and Metastasis in Cholangiocarcinoma / 대한췌담도학회지

Different ligands can lead to the activation of epidermal growth factor receptor, and the subsequent signal transduction leads to an increase in cellular motility, proliferation, invasion, and blocking of apoptosis, and all of this contributes to the development and progression of cancer. Our studies clarified; 1) The EGFR expression level is reduced during tumor progression or during ligand-induced EGFR activation. 2) ANXA8 and its regulatory pathway may well be alternative, strategic targets for inhibiting tumor metastasis. 3) The molecular pathway of EphA2 signaling and provide insight into the mechanisms that control cancer progression and metastatic spread in cholangiocarcinoma (CC). Therefore, therapeutic strategies that target EphA2 and its downstream effectors may be useful to control CC.

Clinical Characteristics and Prognostic Impact of Bacterial Infection in Hospitalized Patients with Alcoholic Liver Disease

Bacterial infection is an important cause of death in patients with liver cirrhosis. The aim of this study was to investigate the clinical characteristics and prognostic impact of bacterial infection in hospitalized patients with alcoholic liver disease (ALD). We retrospectively analyzed data from 409 patients consecutively admitted to a tertiary referral center with ALD diagnosis. Of a total of 544 admissions, 133 (24.4%) cases presented with bacterial infection, of which 116 were community-acquired whereas 17 were hospital-acquired. The common types of infection were pneumonia (38%), biliary tract infection (17%), soft tissue infection (12%), and spontaneous bacterial peritonitis (9%). Diabetes, serum Na or =20 mg/L, systemic inflammatory response syndrome (SIRS) positivity were independently associated with bacterial infection in patients with ALD. Overall 30-day and 90-day mortalities in patients with bacterial infection were significantly (P or =32 (HR, 2.3; 95% CI, 1.036-5.222, P = 0.041), and hemoglobin <12 g/dL (HR, 2.4; 95% CI, 1.081-5.450, P = 0.032) were independent predictors of short-term mortality. In conclusion, bacterial infection and SIRS positivity predicted short-term prognosis in hospitalized patients with ALD. A thorough evaluation at admission or on clinical deterioration is required to detect possible infection with prompt management.

Clinical Features and Risk Factors for Severe Complications among Patients with Acute Hepatitis A Virus Infection in The Jeonbuk Province of Korea / 대한소화기학회지

BACKGROUND/AIMS: The frequency of symptomatic acute HAV infections in adulthood are increasing in Korea. This study analyzes the clinical severity in patients with acute HAV infection and investigates risk factors associated with three severe complications: prolonged cholestasis, acute kidney injury, and acute liver failure. METHODS: We performed a retrospective analysis of 726 patients diagnosed from January 2006 to December 2010 at three tertiary hospitals in Jeonbuk Province, Republic of Korea with acute HAV infection. RESULTS: In the group of 726 patients, the mean age was 30.3 years, 426 (58.6%) were male, and 34 (4.7%) were HBsAg positive. Severe complications from acute HAV infection occurred as follows: prolonged cholestasis in 33 (4.6%), acute kidney injury in 17 (2.3%), and acute liver failure in 16 (2.2%). Through multivariate analysis, age > or =40 years (OR 2.63, p=0.024) and peak PT (INR) > or =1.5 (OR 5.81, p=0.035) were found to be significant risk factors for prolonged cholestasis. Age > or =40 years (OR 5.24, p=0.002) and female gender (OR 3.11, p=0.036) were significant risk factors for acute kidney injury. Age > or =40 years (OR 6.91, p=0.002), HBsAg positivity (OR 5.02, p=0.049), and peak total bilirubin (OR 1.11, p=0.001) were significant risk factors for acute liver failure. CONCLUSIONS: Age > or =40 years, female gender, HBsAg positivity, peak PT (INR) > or =1.5, and peak total bilirubin were significant risk factors for severe complications in acute HAV infections.

A Case of Colonic Adenocarcinoma in a Patient with Wilson's Disease

Wilson's disease (WD) is an autosomal recessive inherited disorder of copper metabolism that results in the accumulation of copper in the body and primarily in the liver, brain, and cornea. Copper is a toxic metal and might be associated with cancer induction. Most malignancies associated with WD are hepatocellular carcinoma and cholangiocarcinoma. Other intra-abdominal malignancies have been only rarely reported. To our knowledge, this is the first report to suggest that patients with WD may be vulnerable to a malignant change in the colonic mucosa during long-term copper chelating therapy. We report a case of colonic adenocarcinoma in a patient with WD and review the related literature.

Parthenolide-induced apoptosis of hepatic stellate cells and anti-fibrotic effects in an in vivo rat model

Parthenolide (PT), a sesquiterpene lactone derived from the plant feverfew, has pro-apoptotic activity in a number of cancer cell types. We assessed whether PT induces the apoptosis of hepatic stellate cells (HCSs) and examined its effects on hepatic fibrosis in an in vivo model. The effects of PT on rat HSCs were investigated in relation to cell growth inhibition, apoptosis, NF-kappaB binding activity, intracellular reactive oxygen species (ROS) generation, and glutathione (GSH) levels. In addition, the anti-fibrotic effects of PT were investigated in a thioacetamide-treated rat model. PT induced growth inhibition and apoptosis in HSCs, as evidenced by cell growth inhibition and apoptosis assays. PT increased the expression of Bax proteins during apoptosis, but decreased the expression of Bcl-2 and Bcl-XL proteins. PT also induced a reduction in mitochondrial membrane potential, poly(ADP-ribose) polymerase cleavage, and caspase-3 activation. PT inhibited TNF-alpha-stimulated NF-kappaB binding activity in HSCs. The pro-apoptotic activity of PT in HSCs was associated with increased intracellular oxidative stress as evidenced by increased intracellular ROS levels and depleted intracellular GSH levels. Furthermore, PT ameliorated hepatic fibrosis significantly in a thioacetamide-treated rat model. In conclusion, PT exhibited pro-apoptotic effects in rat HSCs and ameliorated hepatic fibrosis in a thioacetamide-induced rat model.

Pro-oncogenic potential of NM23-H2 in hepatocellular carcinoma

NM23 is a family of structurally and functionally conserved proteins known as nucleoside diphosphate kinases (NDPK). There is abundant mRNA expression of NM23-H1, NM23-H2, or a read through transcript (NM23-LV) in the primary sites of hepatocellular carcinoma (HCC). Although the NM23-H1 protein is implicated as a metastasis suppressor, the role of NM23-H2 appears to be less understood. Thus, the aim of this study was to examine whether NM23-H2 is associated with hepatocarcinogenesis. The level of NM23-H2 expression in tumor tissues and the surrounding matrix appeared to be independent of etiology and tumor differentiation. Its subcellular localization was confined to mainly the cytoplasm and to a lesser extent in the nucleus. Ectopic expression of NM23-H2 in NIH3T3 fibroblasts and HLK3 hepatocytes showed a transformed morphology, enhanced focus formation, and allowed anchorage-independent growth. Finally, NIH3T3 fibroblasts and HLK3 hepatocytes stably expressing NM23-H2 produced tumors in athymic mice and showed c-Myc over-expression. In addition, NF-kappaB and cyclin D1 expression were also increased by NM23-H2. Lentiviral delivery of NM23-H2 shRNA inhibited tumor growth of xenotransplanted tumors produced from HLK3 cells stably expressing NM23-H2. Collectively, these results indicate that NM23-H2 may be pro-oncogenic in hepatocarcinogenesis.

Long-Term Treatment Efficacy and Safety of Clevudine Therapy in Naive Patients with Chronic Hepatitis B

BACKGROUND/AIMS: Clevudine (CLV) has potent antiviral activity against chronic hepatitis B (CHB) virus infection. The long-term efficacy and safety of CLV therapy in naive patients with CHB were investigated. METHODS: In this retrospective study, 152 naive Korean patients with CHB who received 30 mg of CLV once daily for at least 12 months were investigated. RESULTS: The cumulative rates at months 12, 24, and 36, respectively, were 65.8%, 74.7%, and 74.7% for undetectable serum hepatitis B virus (HBV) DNA ( or =6 log10 IU/mL (p=0.032) and detectable serum HBV DNA (> or =12 IU/mL) at week 24 (p=0.023) were independently associated with the development of viral breakthrough. During follow-up, CLV-induced myopathy developed in 5.9% of patients. CONCLUSIONS: The results of long-term CLV therapy for the treatment of naive patients with CHB showed a high frequency of antiviral resistance and substantial associated myopathy. Therefore, we advise that CLV should not be used as a first-line treatment for naive patients given the availability of other more potent, safer antiviral agents.

Signet-Ring Cell Carcinoma Mimicking Gastric Gastrointestinal Stromal Tumor Confirmed by Endoscopic Ultrasound-Guided Trucut Biopsy

A submucosal gastric adenocarcinoma, especially the signet ring cell type, is rare. The histologic evaluation techniques for this lesion has not been established; however, histologic confirmation is very important for decision of treatment method. Here, we report a 57-year-old man with a 12-cm gastric submucosal signet ring cell type adenocarcinoma, diagnosed by an endoscopic ultrasound-guided Trucut biopsy and immunochemical studies. This case suggests that the endoscopic ultrasound-guided Trucut biopsy might be a useful diagnostic method in cases of gastric adenocarcinoma with features of gastrointestinal stromal tumor.

Antineoplastic effect of endogenous peroxisome proliferator-activated receptor gamma ligand, 15-deoxy-delta(12,14)-prostaglandin J2, on cholangiocarcinoma cells / 대한내과학회지

BACKGROUND/AIMS: Peroxisome proliferator-activated receptor (PPAR)-gamma ligand is known to inhibit the growth of several kinds of cancer cells, yet its effect on cholangiocarcinoma is indecisive. We investigated the effect of an endogenous ligand of PPAR-gamma, 15-deoxy-delta (12,14)-prostaglandin J2 (15-deoxy-PGJ2) on cholangiocarcinoma cells that were established from intrahepatic cholangiocarcinoma tissue of Korean patients. METHODS: Four cholangiocarcinoma cell lines, Cho-CK, Choi-CK, JCK and SCK, were studied. The mRNA expression of PPAR-gamma, bcl-2, and bax were examined by RT-PCR. Cell viability was determined by MTT assay. The cell cycle was analyzed by flow cytometry, and apoptosis by cell death detection ELISA kit. Caspase activity was measured by colorimetric assay. The effect of caspase inhibitors on 15-deoxy-PGJ2-induced apoptosis was determined by measuring cell viability using the MTT assay. RESULTS: PPAR-gamma mRNA was expressed in all cholangiocarcinoma cells. 15-deoxy-PGJ2 inhibited proliferation of all cells in a dose- and time-dependent manner. All cells treated with 15-deoxy-PGJ2 showed increased dose-dependent apoptosis. Caspase 3 was activated in all cells and caspase 9 was activated in all but JCK cells after 15-deoxy-PGJ2 treatment. Caspase 8 activity showed no significant change. The pan-caspase inhibitor, Z-VAD-FMK, and the caspase-3 inhibitor, Z-DEVD-FMK, blocked 15-deoxy-PGJ2-induced apoptosis in all cells dose-dependently. The expression of bcl-2 was decreased in Cho-CK, Choi-CK and SCK cells, and bax expression was not changed significantly after 15-deoxy-PGJ2 treatment. CONCLUSIONS: PPAR-gamma mRNA was expressed in all Korean cholangiocarcinoma cells. Our data suggest that 15-deoxy-PGJ2 exerts an antineoplastic effect against cholangiocarcinoma cells by inducing apoptosis through caspase activation.

A Case of Rectal Cancer in a Patient with X-linked Agammagloubulinemia / 대한소화기내시경학회지

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency disorder caused by germline mutation of the Bruton tyrosine kinase (BTK) gene. Most of the patients diagnosed X-LA suffer from recurrent infections of the respiratory and gastrointestinal tracts. Increased risk of malignancy in X-LA patients include lymphoma, gastric cancer, colorectal cancer. We report a case of 32-years-old male patient with X-linked agammagolbulinemia and rectal cancer. Agammaglobulinemia was diagnosed at 13 years old. He underwent colonoscopy for hematochezia. An ulceroinfiltrative mass was found during colonscopy and biopsy revealed moderately differentiated adenocarcinoma. Subsequently, he underwent a anterior resection.

Treatment Outcomes of Clevudine versus Lamivudine at Week 48 in Naive Patients with HBeAg Positive Chronic Hepatitis B

The authors assessed the efficacy and antiviral resistance of 48-week clevudine therapy versus lamivudine in treatment of naive patients with HBeAg positive chronic hepatitis B. In this retrospective study, a total of 116 HBeAg positive patients, who received 30 mg of clevudine once daily (n=53) or 100 mg of lamivudine once daily (n=63) for 48 weeks, were included. At week 48, clevudine therapy produced a significantly greater mean reductions in serum HBV DNA levels from baseline than lamivudine therapy (-5.2 vs. -4.2 log(10)IU/mL; P=0.005). Furthermore, a significantly higher proportion of patients on clevudine achieved negative serum HBV DNA by PCR (<13 IU/mL) at week 48 (60.4% vs. 38.1%; P=0.025). The incidence of virologic breakthrough in the clevudine group was significantly lower than in the lamivudine group (9.4% vs. 25.4%; P=0.031). However, rates of alanine aminotransferase normalization and HBeAg loss or seroconversion were similar in the two groups (83.0% vs. 81.0%, 11.3% vs. 11.1%; P=0.813, 1.000, respectively). In conclusion, clevudine is more potent for viral suppression and lower for antiviral resistance at week 48 than lamivudine in treatment of naive patients with HBeAg positive chronic hepatitis B.

Enhancement of parthenolide-induced apoptosis by a PKC-alpha inhibition through heme oxygenase-1 blockage in cholangiocarcinoma cells

Cholangiocarcinoma (CC) is a chemoresistant intrahepatic bile duct carcinoma with a poor prognosis. The aims of this study were to identify molecular pathways that enhance sesquiterpene lactone parthenolide (PTL)-induced anticancer effects on CC cells. The effects of PTL on apoptosis and hemoxygenase-1 (HO-1) induction were examined in CC cell lines. The enhancement of PTL-mediated apoptosis by modulation of HO-1 expression and the mechanisms involved were also examined in an in vitro cell system. Low PTL concentrations (5 to 10 micrometer) led to Nrf2-dependent HO-1 induction, which attenuated the apoptogenic effect of PTL in Choi-CK and SCK cells. PTL-mediated apoptosis was enhanced by the protein kinase C-alpha inhibitor Ro317549 (Ro) through inhibition of expression and nuclear translocation of Nrf2, resulting in blockage of HO-1 expression. Finally, HO-1 silencing resulted in enhancement of apoptotic cell death in CC cells. The combination of PTL and Ro efficiently improved tumor growth inhibition compared to treatment with either agent alone in an in vivo subcutaneous tumor model. In conclusion, the modulation of HO-1 expression substantially improved the anticancer effect of PTL. The combination of PTL and Ro could prove to be a valuable chemotherapeutic strategy for CC.

A Case of Afferent Loop Syndrome after Inserting a Double-Layered Pyloric Stent for Gastric Outlet Obstruction in a Patient with Stump Gastric Cancer after Undergoing Billroth II Radical Subtotal Gastrectomy / 대한소화기내시경학회지

Stent insertion is an effective method for treating a patient with gastric outlet obstruction that's caused by recurred cancer at the anastomosis site. There are some complications associated with stent insertion, such as perforation, bleeding, ulceration and obstruction. There are only rare Korean case reports of afferent loop syndrome after stent insertion. We report here on a case of afferent loop syndrome that occurred after insertion of a double-layered pyloric stent for gastric outlet obstruction in a patient with stump gastric cancer after undergoing Billroth II radical subtotal gastrectomy.

Involvement of GADD153 and cardiac ankyrin repeat protein in cardiac ischemia-reperfusion injury

Oxidative stress is critical for causing cardiac injuries during ischemia-reperfusion (IR), yet the molecular mechanism for this remains unclear. In the present study, we observe that hypoxia and reoxygenation, a component of ischemia, effectively induces apoptosis in the cardiac myocytes from neonatal rats and it concomitantly leads to induction of GADD153, an apoptosis-related gene. Furthermore, IR injury of rat heart showed a GADD153 overexpression in the ischemic area where the TUNEL reaction was positive. A downregulation of cardiac ankyrin repeat protein (CARP) was also observed in this ischemic area. Promoter deletion and reporter analysis revealed that hypoxia transcriptionally activates a GADD153 promoter through the AP-1 element in neonatal cardiomyocytes. Ectopic overexpression of GADD153 resulted in the downregulation of CARP expression. Accordingly, the induction of GADD153 mRNA were followed by the CARP down-regulation in an in vivo rat coronary ischemia/reperfusion injury model. These results suggest that GADD153 over-expression and the resulting downregulation of CARP may have causative roles in apoptotic cell death during cardiac IR injury.

A Case of Intrahepatic Choledochal Web That Was Diagnosed by Percutaneous Transhepatic Cholangioscopy and It Was Treated with Balloon Dilatation: Review of the Korean Cases / 대한소화기내시경학회지

Choledochal web is an extremely rare disease and it is frequently associated with bile duct stone that causes biliary obstruction and cholangitis. Most cases of choledochal web have been found incidentally during a surgical procedure or on autopsy because of its rare incidence and the absence of specific clinical manifestations. Yet making an early diagnosis has become feasible with the development of radiologic studies. All twelve cases of choledochal web, reported in Korea, were located in the extrahepatic duct, and were diagnosed with an operation, endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography. We report here on a case of intrahepatic choledochal web that was well visualized by percutaneous transhepatic choledochoscopy and it was treated with balloon dilatation.

Genetic and expression alterations in association with the sarcomatous change of cholangiocarcinoma cells

Cholangiocarcinoma (CC) is an intrahepatic bile duct carcinoma with a high mortality rate and a poor prognosis. Sarcomatous change/epithelial mesenchymal transition (EMT) of CC frequently leads to aggressive intrahepatic spread and metastasis. The aim of this study was to identify the genetic alterations and gene expression pattern that might be associated with the sarcomatous change in CC. Previously, we established 4 human CC cell lines (SCK, JCK1, Cho-CK, and Choi-CK). In the present study, we characterized a typical sarcomatoid phenotype of SCK, and classified the other cell lines according to tumor cell differentiation (a poorly differentiated JCK, a moderately differentiated Cho-CK, and a well differentiated Choi-CK cells), both morphologically and immunocytologically. We further analyzed the genetic alterations of two tumor suppressor genes (p53 and FHIT) and the expression of Fas/FasL gene, well known CC-related receptor and its ligand, in these four CC cell lines. The deletion mutation of p53 was found in the sarcomatoid SCK cells. These cells expressed much less Fas/FasL mRNAs than did the other ordinary CC cells. We further characterize the gene expression pattern that is involved in the sarcomatous progression of CC, using cDNA microarrays that contained 18,688 genes. Comparison of the expression patterns between the sarcomatoid SCK cells and the differentiated Choi-CK cells enabled us to identify 260 genes and 247 genes that were significantly over-expressed and under-expressed, respectively. Northern blotting of the 14 randomly selected genes verified the microarray data, including the differential expressions of the LGALS1, TGFBI, CES1, LDHB, UCHL1, ASPH, VDAC1, VIL2, CCND2, S100P, CALB1, MAL2, GPX1, and ANXA8 mRNAs. Immunohistochemistry also revealed in part the differential expressions of these gene proteins. These results suggest that those genetic and gene expression alterations may be relevant to the sarcomatous change/EMT in CC cells.

A Case of Dieulafoy-like Lesion with Massive Bleeding at Ileocecal Valve Following Acute Infectious Colitis in a Pediatric Patient / 대한소화기내시경학회지

The common causes of lower gastrointestinal bleeding in children are intussusception, rectal juvenile polyp, chronic inflammatory colitis and Meckel's diverticulum. Bleeding from Dieulafoy's ulcer at the lower gastrointestinal tract is rare, but this often occurs in the rectum. So far, there has been no report that a Dieulafoy lesion in the ileocecal valve might be formed after acute colitis in a pediatric patient. In this case report, a Dieulafoy-like lesion at the ileocecal valve caused lower gastrointestinal bleeding in an asymptomatic 14-year-old woman. A careful history taking and medical examination are mandatory to identify the bleeding focus in the GI tract and this can be treated by endoscopy.