Usefulness of autofluorescence imaging for estimating the extent of gastric neoplastic lesions: a prospective multicenter study

BACKGROUND/AIMS

The aim of this study was to determine whether the margin of early to be detected gastric cancer (EGC) and gastric adenoma is easier to be detected with autofluorescence imaging (AFI) than with white-light endoscopy (WLE).

METHODS

A total of 102 lesions (48 EGCs and 54 gastric adenomas) found in 98 patients were removed endoscopically or surgically. The measured length of each pathology specimen was compared with the lengths estimated using WLE, AFI, and chromoendoscopy.

RESULTS

The lesions could be discriminated from surrounding mucosa by AFI in 86 cases (84.3%). The detection rates were similar for elevated lesions (85.1%) and flat/depressed lesions (82.9%, p=0.770). In terms of histology, the detection rate was slightly higher for adenomas (90.7%) than for cancer (77.1%, p=0.058). The estimated length was shorter than the pathologic length in 31.4% of cases when using WLE and 22.1% of cases when using AFI (p=0.168). The resection range was larger for EMR than for AFI in 24 of 80 cases (30.0%).

CONCLUSIONS

WLE tends to underestimate the size of EGCs, whereas AFI tends to overestimate their size.

[A case of Sister Mary Joseph's nodule as a presenting sign of gastric cancer]

The cutaneous metastasis of a visceral malignancy to the umbilicus is known as "Sister Mary Joseph's nodule (SMJN)". It is considered to be a predictor of poor prognosis because it mostly occurs in advanced, metastasizing cancer. However, it is a very rare condition as an initial presenting sign of primary cancer. We recently encountered a 48-year-old man presented with an umbilical lump. The lesion was a firm, ill-delineated, painful nodule with regular surface in the umbilicus. Abdominal computed tomography showed a 2.2 cm sized, ill-defined, delayed enhancing mass at the periumbilical area accounting for umbilical nodule. Diffuse irregular thickening of peritoneum and diffuse wall thickening of stomach implied the diagnosis of gastric cancer. Esophagogastroduodenoscopy revealed diffuse nodular infiltrative lesion from cardia through body of the stomach, compatible with Bormann type 4 advanced gastric cancer. Later, histopathologic confirmation showed a presence of signet ring cell adenocarcinoma from biopsy specimens. We experienced a case presenting with an umbilical metastasis as the first sign of gastric adenocarcinoma. It is thought that direct extension of tumor through the peritoneum might be the route for umbilical metastasis. Careful examination of all umbilical lesions must be needed for the early diagnosis of internal malignancy.

Diagnostic utility of interleukin-6 (IL-6) for primary bile duct cancer and changes in serum IL-6 levels following photodynamic therapy

OBJECTIVES

Difficult diagnoses and a lack of effective therapy complicate biliary tract malignancies. Interleukin-6 (IL-6) is a human bile duct epithelium growth factor correlated with tumor burden. We evaluated the usefulness of serum IL-6 in the diagnosis of primary BDC and measured changes in serum IL-6 levels following photodynamic therapy (PDT).

METHODS

We prospectively measured serum IL-6 levels in patients with BDC (N = 26: 14 patients treated with PDT, 12 with biliary drainage alone), hepatocelluar carcinoma (HCC, N = 26), and healthy adults (N = 23). Serum IL-6 levels were measured by an enzyme-linked immunosorbent assay. Patients with clinical conditions known to increase IL-6 levels were excluded.

RESULTS

IL-6 was detected in all patients with BDC and HCC, and in 6 of 23 healthy adults. Median and mean levels of IL-6 were higher in patients with BDC than in both other groups (P < 0.001). Using a 25.8 pg/mL cutoff, IL-6 provided a diagnostic sensitivity of 73% and a specificity of 92%; positive and negative predictive values were 83% and 87%, respectively. Serum levels of IL-6 were correlated with tumor burden in BDC patients. One month after treatment of BDC with PDT, the mean IL-6 level decreased significantly from 282.1 +/- 121.8 to 38.2 +/- 9.9 pg/mL (P= 0.008).

CONCLUSIONS

Serum IL-6 concentration is a useful addition to the available tests for the differential diagnosis of BDC, and serves as a marker for monitoring the response to treatment of BDC with PDT.

[Etiologic and laboratory analyses of ascites in patients who underwent diagnostic paracentesis]

BACKGROUND/AIMS

Liver cirrhosis and malignant tumors are two major causes of ascites according to the reports from Western countries, 80% and 10% respectively. Assuming that there might be regional differences in etiologies and changes in their frequency over time, we investigated causes of ascites and the diagnostic usefulness of various laboratory tests.

METHODS

Medical records of 366 patients, who underwent diagnostic paracentesis in the mid-1990s (1996 and 1997) and early 2000s (2001 and 2002), were retrospectively reviewed. The etiology was confirmed by histology, imaging studies, and ascites analyses.

RESULTS

The frequency of cirrhotic ascites was 59.6%, cancer-related 25.7%, tuberculous peritonitis 6.6%, and others 8.1%. Among cirrhotics, the frequency of cases related to hepatitis B decreased significantly from 72% to 55% over time, and alcoholic cirrhosis increased from 18% to 34%. Among cancer-related ascites, peritoneal carcinomatosis type was 75.5% (primary sites: stomach 24.5%, pancreas 15.9%, colon 15.9%, lung 7.4%, etc), metastatic liver cancers 8.5%, hepatocellular carcinoma without cirrhosis 6.4%, etc. The sensitivity of serum-ascites albumin gradient for the diagnosis of cirrhotic ascites was 91.4%, and total protein in ascites also revealed a comparable diagnostic sensitivity, 90%. The diagnostic sensitivity of adenosine deaminase for tuberculous peritonitis was 94.2%, and its positive predictive value was 75%.

CONCLUSIONS

Liver cirrhosis is the leading cause of ascites, especially alcoholic cirrhosis has significantly increased. The next common etiology is cancer-related, and its frequency in Korea is higher than in western countries. Tuberculous peritonitis is still prevalent, and adenosine deaminase could precisely differentiate it from other causes.

Extrahepatic biliary schwannomas: a case report

Benign schwannomas arise in neural crest-derived Schwann cells. They can occur almost anywhere in the body, but their most common locations are the central nervous system, extremities, neck, mediastinum, and retroperitoneum. Schwannomas occurring in the biliary tract are extremely rare and mostly present with obstructive jaundice. We recently experienced a case of extrahepatic biliary schwannomas in a 64-yr-old female patient who presented with intra- and extrahepatic bile duct and gallbladder stones during a screening program. To the best of our knowledge, extrahepatic biliary schwannomas associated with bile duct stones have not been reported previously in the literature.

[Long-term results of endoscopic histoacryl (N-butyl-2-cyanoacrylate) injection for treatment of gastric varices--a 10-year experience]

BACKGROUND/AIMS

Gastric variceal bleeding is an infrequent but serious complication of portal hypertension. Endoscopic injection of Histoacryl (N-butyl-2-cyanoacrylate) has been approved as an effective treatment for gastric variceal bleeding. The aim of this study was to evaluate the long-term efficacy and safety of the endoscopic injection of Histoacryl for the treatment of gastric varices.

METHODS

Between January 1994 and January 2005, eighty-five patients with gastric varices received endoscopic injections of Histoacryl. Among these 85 patients, 65 received the procedure within 1 week after gastric variceal bleeding, and 13 received as a prophylactic procedure. According to the Sarin classification, 32 patients were GOV1 and 53 were GOV2. Most of the varices were large (F2 or F3, 75 patients). The average volume of Histoacryl per each session was 1.43 ml. Among 85 patients, 72 patients were followed-up and the median duration was 24.5 months.

RESULTS

The rate of initial hemostasis was 98.6% and recurrent bleeding occurred in 29.2% (21 of 72). When rebleeding occurred, 76.2% was within 1 year after the initial injection. Treatment failure-related mortality rate was 1.4% (1 of 85). Twenty-seven patients died, mostly due to hepatocelluar carcinoma or liver failure. Two patients experienced pulmonary embolism and one experienced splenic infarction. They recovered without specific treatment. Rebleeding rate had a tendency to increase in patients with hepatocelluar carcinoma (p=0.051) and GOV2 (p=0.061).

CONCLUSIONS

Histoacryl injection therapy is a effective treatment method for gastric varices with high initial hemostasis rate and low major complications.

[Clinical usefulness of DeltaMELD to predict the survival of patients with liver cirrhosis]

BACKGROUNDS/AIMS

The change of MELD (Model for End-stage Liver Disease) score over time (DeltaMELD) has been proposed as a tool to predict the survival in cirrhotic patients. The aims of the study were to assess ability of the DeltaMELD to predict the survival and compare them with the initial MELD and CP score.

METHODS

MELD score was serially determined at least twice with more than two-month interval in 120 cirrhotic patients. We analyzed the clinical factors associated with the variation of MELD score. The predictive power of 6, 12 and 24 months mortality for DeltaMELD, initial MELD and CP score was compared by c-statistics. Patient survival was also compared at 6, 12 and 24 months according to the cut off values of DeltaMELD/month, initial MELD and CP score.

RESULTS

Increased MELD score was associated with biochemical and clinical parameters such as esophageal variceal bleeding and onset of hepatic encephalopathy. The area under receiver operating characteristic (ROC) curve for DeltaMELD/month was 0.928 (P<0.001) compared with 0.575 for MELD score and 0.636 for CP score at 6 month-mortality; the area was 0.727, 0.594 and 0.657 at 12 month-mortality; 0.693, 0.587 and 0.639 at 24 month-mortality, respectively. The patients with DeltaMELD/month more than 1.0 had resulted in the higher mortality at 6, 12 and 24 months. The DeltaMELD/month was associated with mortality and was an independent prognostic predictor with a risk ratio of 1.679 (95% CI: 1.381-2.042, P<0.001).

CONCLUSIONS

Determination of DeltaMELD could be better prognostic predictor for patients with liver cirrhosis than initial MELD and CP score.

Pancreatitis from metastatic small cell lung cancer successful treatment with endoscopic intrapancreatic stenting

Lung cancer metastases can occur in almost any organ. However, metastasis of small cell lung cancer to the pancreas is rare. Moreover, not all cases present with clinically diagnosed pancreatitis. We recently treated a patient with small cell lung carcinoma that invaded the pancreatic duct causing acute pancreatitis. Generally, the treatment for tumor-induced acute pancreatitis is initially supportive followed by aggressive chemotherapy or surgery. If the patient can tolerate the insertion of an endoscopic intrapancreatic stent, this is performed in addition to chemotherapy and surgery; this approach offers a safe and effective treatment modality for such patients.

[Clinical significance of intrahepatic HCV RNA level in chronic HCV infection]

BACKGROUND/AIMS

This study was carried out to identify the correlation between the serum HCV RNA and the liver HCV RNA level in chronic hepatitis C patients and to evaluate the differences of biochemistry, histology, HCV genotype and their response to antiviral therapy according to intrahepatic HCV RNA levels.

METHODS

For thirty-six chronic hepatitis C patients (M:F=22:14, CH:LC=27:9), percutaneous liver biopsy was performed, and serum and liver HCV RNA level were measured. Seventeen patients were treated with IFN-alpha and ribavirin.

RESULTS

There was a significant correlation between intrahepatic and serum HCV RNA levels (intrahepatic HCV RNA: 1.9+/-3.1 x 10(7) copies/g vs. serum HCV RNA: 3.2+/-3.2 x 10(6) copies/mL)(r=0.538, P<0.01). Total histological activity score (r=0.346, P=0.04) and periportal inflammation (r=0.398, P=0.01) were correlated with intrahepatic HCV RNA level. However, serum HCV RNA level was not correlated with histological activity. Serum ALT was not correlated with intrahepatic HCV RNA level. Intrahepatic HCV RNA level was higher in genotype 1 than genotype 2 or 3 (P=0.07). Intrahepatic HCV RNA level was not correlated with response to anti-viral therapy.

CONCLUSION

Intrahepatic HCV RNA level was correlated with serum HCV RNA level and periportal inflammation in patients with chronic hepatitis C. It seems that intrahepatic HCV RNA level is more closely related to histological features than serum HCV RNA level.

[Risk of postoperative infection in patients with inflammatory bowel disease]

BACKGROUND/AIMS

The clinical course of patients with inflammatory bowel disease (IBD) frequently leads to the use of immunosuppressants and immunomodulators. We investigated the risk of postoperative infection in patients with IBD undergoing elective bowel surgery and whether the use of corticosteroid (CS) and/or 6-mercaptopurine/ azathioprine (6-MP/AZA) before surgery was associated with the increased risk of postoperative infection.

METHODS

Patients who were diagnosed as Crohn's disease (n=25) or ulcerative colitis (n=19) and underwent elective bowel surgery between 1986 and 2005 were identified. Medical records were retrospectively analyzed including age, sex, duration of disease, indication for surgery, duration of surgery, type of surgery, type of postoperative infection, admission period, usage of CS and 6-MP/AZA, and preoperative laboratory values. There were 27 patients receiving CS alone, 6 patients receiving 6-MP/AZA alone or with CS, and 16 patients receiving neither CS nor 6-MP/AZA.

RESULTS

There were 17 postoperative infections (38.6%) among IBD patients who had undergone surgery and wound infection was the most common type of infection (76.5%). In IBD patients, patients receiving CS had higher postoperative infection rate than those patients receiving neither CS nor 6-MP/AZA (p=0.039). Patients receiving CS in conjunction with 6-MP/AZA did not have significantly higher postoperative infection rate than those with CS only (p=0.415).

CONCLUSIONS

Preoperative use of CS in patients with IBD is associated with the increased risk of postoperative infections. Addition of 6-MP/AZA in patients receiving CS does not increase the risk of postoperative infections.

[Magnifying endoscopy in upper gastrointestinal tract]

For the diagnosis of upper gastrointestinal (GI) lesions, magnification method is usually used in conjunction with chromoscopy, enabling the endoscopist to view subtle mucosal patterns in exquisite detail. Recently published datas have shown that magnifying endoscopy might be a valuable adjunct for the diagnosis, detection, and characterization of inflammatory and neoplastic lesions of the upper GI tract. It is also proven to be an useful surveillance protocol in identifying dysplastic epithelium or early cancer within a segment of Barrett's esophagus. Possible indications for magnifying endoscopy in upper GI tract include screening and surveillance of Barrett's esophagus, defining the extent of esophageal and gastric adenocarcinoma, detecting synchronous/metachronous gastric and esophageal cancers, diagnosing Helicobacter pylori infection, and recognizing minimal mucosal changes in gastroesophageal reflux disease. By grading the quality of evidence for the currently published trials, it is clear that the majority are case series, case reports, and/or observational studies without randomization, control, or blinding. Moreover, other evidence-based criteria such as independent, blind comparisons of magnifying endoscopy with a standard method which evaluates this technology in an appropriate spectrum of patients to whom the test may be applicable, and standardizing methodology would be crucial before magnifying endoscopy becomes a standard procedure in clinical practice. In the future, a uniform classification system for staining and magnifying patterns should be devised and observer agreement should be tested. Futher studies then could be performed based upon consistent, validated, and standardized terminologies and criteria.

[A case of complete regression of hepatocellular carcinoma during administration of COX-2 inhibitor]

Overexpression of cyclooxygenase-2 (COX-2) has been associated with hepatocarcinogenesis. Inhibitors of COX-2 have proapoptotic and antiproliferative effects on malignant tumors and inhibit tumor invasion to the surrounding tissues. We report here a case of complete regression of advanced hepatocellular carcinoma (HCC) during COX-2 inhibitor administration. An eighty-year-old female was diagnosed as an advanced HCC, which was associated with HCV infection. She received COX-2 inhibitor for 3 months due to degenerative arthritis of both knees. Tumor enhancement on arterial phase CT completely disappeared without specific treatment for the HCC, and the tumor size decreased on the follow-up CT scan.

Expression profiling of radiation-induced genes in radiodermatitis of hairless mice

BACKGROUND

Radiation induces many cellular events leading to radiodermatitis.

OBJECTIVES

The aim of this study was to establish a radiodermatitis model using experimental animals, and to examine the expression profile of radiation-induced genes.

METHODS

Hairless mice were irradiated on the dorsal skin; then total RNAs were isolated and microarray hybridizations were performed.

RESULTS

Irradiation with a total of 40 Gy (10 Gy day-1 for four consecutive days) provokes radiodermatitis in the hairless mouse. After microarray analysis, 130 genes that showed upregulation by radiation were selected and organized into four different clusters, depending on the time-kinetic pattern. Classification of these genes into several functional categories revealed that various biological processes were globally affected by radiation. These include transcription regulation, signal transduction, cell communication, cell death regulation and metabolism.

CONCLUSIONS

These results demonstrate the complexity of the transcriptional profile of the radiation response, providing important clues on which to base further investigations of the molecular events underlying radiodermatitis.

[Detection of Intrahepatic HBV DNA in HBsAg-negative liver diseases]

BACKGROUNDS/AIMS

Occult HBV infection is characterized by the presence of HBV infection with undetectable HBsAg. This study was carried out to find out the frequency of HBV infection in HBsAg- negative patients.

METHODS

Fifty-six HBsAg-negative patients including 17 anti-HCV positive patients were evaluated. Patients were grouped according to their serological status; group A (anti-HBc+, anti-HBs-, n=16), B (anti-HBc+, anti-HBs+, n=26), and C (anti-HBc-, anti-HBs+/-, n=14). DNA was extracted from frozen liver biopsy specimen, and HBV DNA level was measured with real-time PCR.

RESULTS

Overall frequency of detectable intrahepatic HBV DNA was 34% (19/56). The frequency was 56% (9/16) in group A, 31% (8/26) in group B and 14% (2/14) in group C (P=0.01). Intrahepatic HBV DNA levels were as follows; 2,010 +/- 6,660 copies/mg in group A, 6,180 +/- 29,530 copies/mg in group B and 350 +/- 1,220 copies/mg in group C. The frequency of occult HBV infection was not increased in anti-HCV positive patients.

CONCLUSIONS

Intrahepatic HBV DNA is frequently detected in anti-HBc positive, HBsAg-negative patients, although the concentration is low.

[A case of stump MALT lymphoma after partial gastrectomy]

Gastrectomy is known to be a risk factor for adenocarcinoma in remnant stomach. It is suggested that reflux of bile juice or duodenal secretion to remnant stomach induces atrophic gastritis, intestinal metaplasia, and gastric adenocarcinoma. Malignant lymphoma in remnant stomach after gastrectomy is very rare. Only about thirty cases are reported in the world, and there is no case report in Korea. Gastric MALT (mucosa-associated lymphoid tissue) lymphoma is associated with Helicobacter pylori infection but the mechanism of lymphoma development in remnant stomach is still unknown. We report a case of low grade gastric MALT lymphoma of gastric stump after 10 years from partial gastrectomy.

A case of santorinicele without pancreas divisum: diagnosis with multi-detector row computed tomography

A santorinicele is defined as a focal cystic dilatation of the terminal portion of the dorsal pancreatic duct at the minor papilla. Most cases reported previously were associated with pancreas divisum and a santorinicele without pancreas divisum is known to be rare. We recently experienced a typical case of a santorinicele without pancreas divisum in a 67-yr-old woman with abdominal pain and hematochezia, subsequently proven to be the result of an ischemic colitis. The santorinicele was diagnosed incidentally with multi-detector row computed tomography using a minimum intensity projection technique, which clearly showed a cystic dilatation of the terminal portion of the dorsal pancreatic duct and a communication between the ventral and dorsal pancreatic ducts. This finding was also confirmed by a magnetic resonance cholangiopancreatography.

[The role of smoking as a risk factor in inflammatory bowel diseases: single center study in Korea]

BACKGROUND/AIMS

Cigarette smoking is the most significant environmental factor identified in inflammatory bowel disease (IBD). Smoking has a beneficial effect on ulcerative colitis (UC) patients. In contrast, Crohn's disease (CD) is associated with smoking, and a detrimental effect of smoking on the course of CD has been demonstrated. The aim of this study was to explore the prevalence in smoking in CD and UC at the time of diagnosis compared with the general population in a single center study.

METHODS

Prevalence of smoking at the time of IBD diagnosis were compared between CD and UC patients in Kyung-Hee Medical Center with healthy general population at age-, gender-, and time period-adjusted rates. We investigated the smoking status of IBD patients at the time of diagnosis by telephone interview. There were 178 IBD patients (98 UC patients and 80 CD patients) between January 1995 and December 2004.

RESULTS

The male to female ratio in CD and UC were 2:1 and 1:1.4, respectively. The onset of age was 28.2 years and 38.8 years, respectively. The prevalence of smoking was significantly lower in CD and UC patients than in the general population (CD; odds ratio 0.21, 95% confidence interval 0.12-0.41, p<0.001, UC; odds ratio 0.06, 95% confidence interval 0.03-0.14, p<0.001). After statistical adjustment for gender and age at the diagnosis of IBD, the odds ratio of a current smoker diagnosed as UC was 73% lower than that of CD (adjusted odds ratio 0.27, 95% confidence interval 0.12-0.59, p<0.001). In contrast, being a former smoker showed a risk of approximate 1.27-fold higher likelihood of having UC diagnosis (adjusted odds ratio 1.27, confidence interval 0.41-3.95, p=0.68).

CONCLUSIONS

Cigarette smoking is protective against developing UC at any age, but is not associated with the development of CD in Korean population. Former smoking is not the high risk factor in developing UC.

[A case of idiopathic colitis developed after barium enema]

It has been reported that colitis may be associated with intrarectally administered drugs or chemicals. Colonotoxicity may results from conventional medical therapy, herbal or other illicit drugs, contrast materials, and detergents. Clues that a colitis may be due to an intrarectally administered agent include perianal excoriation, segmental distal colitis due to a concentration gradient from enema administration, and recent diagnostic or therapeutic administration of high risk solutions such as hypertonic contrast agents or detergent enemas. Barium is a highly viscous contrast agent that is insoluble in water. Barium enemas are usually very safe. Also, no case report of barium-induced chemical colitis has been reported yet. We report a case of chemical colitis with colonic stricture occurring after the barium enema for diagnostic purpose.

[The incidence and clinical significance of paraneoplastic syndromes in patients with hepatocellular carcinoma]

BACKGROUND/AIMS

Patients with hepatocellular carcinoma (HCC) may manifest paraneoplastic syndromes such as hypercholesterolemia, hypoglycemia, hypercalcemia and erythrocytosis. This study was aimed at evaluating the incidence and clinical significance of paraneoplastic syndromes in Korean HCC patients.

METHODS

The medical records of 165 HCC patients who were diagnosed and died in the Kyung Hee University Hospital, were reviewed retrospectively. The following variables were analyzed: age, gender, hepatitis markers, platelet, liver function test, alpha-fetoprotein (AFP), Child-Pugh score, tumor features, and the duration of their survival.

RESULTS

In total, paraneoplastic syndromes were presented in 43.6% of the HCC patients during the course of their disease. Hypercholesterolemia was solely presented in 14.5%, hypoglycemia in 12.7% and hypercalcemia in 7.8%. The patients who presented with more than 2 syndromes were 8.5%. While 80% of erythrocytosis (4/5) and 51.6% of hypercholesterolemia (16/31) was presented at the time of HCC diagnosis, hypoglycemia and hypercalcemia mainly occurred as terminal events. The patients with paraneoplastic syndromes were younger and had higher rates of portal vein thrombosis, bi-lobar tumor involvement and tumor more of more than 10 cm in diameter, compared to those patients without them. The proportion of patients with a serum AFP more than 400 ng/mL tended to be higher in the patients with paraneoplastic syndromes. The HCC patients with paraneoplastic syndromes, except for erythrocytosis, had a shorter survival than those patients without them.

CONCLUSIONS

Paraneoplastic syndromes are not infrequently presented in HCC patients, especially at an advanced stage, and the survival of these patients is relatively shorter.

[Saccharomyces boulardii activates expression of peroxisome proliferator-activated receptor-gamma in HT-29 cells]

BACKGROUND/AIMS

Saccharomyces boulardii (S. boulardii) has been reported to be beneficial in the treatment of inflammatory bowel disease, however, little is known about its mechanism of action. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is recently found to regulate inflammation in intestinal epithelial cells. We hypothesized that the anti-inflammatory effects of S. boulardii are mediated, in part, through PPAR-gamma. To test this hypothesis, we examined the ability of S. boulardii to modulate the expression of PPAR-gamma in human colon cells.

METHODS

Effects of S. boulardii on survival and proliferation of HT-29 human colon cells were assessed by MTT and [3H]thymidine incorporation assays. PPAR-gamma expression was assessed by Western blot and RT-PCR. Induction of interleukin-8 (IL-8) expression by tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), or lipopolysaccharide (LPS) was assessed by RT-PCR.

RESULTS

S. boulardii did not affect viability and proliferation of HT-29 cells. S. boulardii up-regulated PPAR-gamma expression at both mRNA and protein levels. Pretreatment of HT-29 cells with S. boulardii blocked PPAR-gamma down-regulation by TNF-alpha, IL-1beta, or LPS, whereas it ameliorated IL-8 response to these proinflammatory factors.

CONCLUSIONS

S. boulardii stimulates PPAR-gamma expression and reduces response of human colon cells to proinflammatory cytokines.

[Frequent epigenetic inactivation of XAF1 by promotor hypermethylation in human colon cancers]

BACKGROUND/AIMS

X-linked inhibitor of apoptosis (XIAP) is the most potent member of the IAP family that exerts antiapoptotic effects. Recently, XIAP-associated factor 1 (XAF1) and two mitochondrial proteins, Smac/ DIABLO and HtrA2, have been identified to negatively regulate the caspase-inhibiting activity of XIAP. We explored the candidacy of XAF1, Smac/DIABLO and HtrA2 as a tumor suppressor in colonic carcinogenesis.

METHODS

Expression and mutation status of the genes in 10 colorectal carcinoma cell lines and 40 primary tumors were examined by quantitative PCR analysis.

RESULTS

XAF1 transcript was not expressed or present at extremely low levels in 60% (6/10) of cancer cell lines whereas Smac/DIABLO and HtrA2 are normally expressed in all cell lines examined. Tumor-specific loss or reduction of XAF1 was also found in 35% (14/40) of matched tissue sets obtained from the same patients. XAF1 transcript was reactivated in all the low expressor cell lines by treatment with the demethylating agent 5-aza-2'-deoxycytidine. Moreover, bisulfite DNA sequencing analysis for 34 CpG sites in the promoter region revealed a strong association between hypermethylation and gene silencing. Restoration of XAF1 expression resulted in enhanced apoptotic response to etoposide and 5-flurouracil, whereas knockdown of XAF1 expression by siRNA transfection significantly inhibited chemotherapeutic drug-induced apoptosis.

CONCLUSIONS

XAF1 undergoes epigenetic gene silencing in a considerable proportion of human colon cancers by aberrant promoter hypermethylation, suggesting that XAF1 inactivation might be implicated in colonic tumorigenesis.

[Positive predictability and predictive factors of the third generation anti-hepatitis C virus (HCV) ELISA test for HCV infection]

BACKGROUND/AIMS

Anti-HCV positivity suggests past or present infection of HCV, or false positivity. The positive predictability of this test can differ according to the subjects. This study examines the positive predictability of the third generation anti-HCV ELISA and factors predicting HCV infection with special emphasis on the significance of the anti-HCV sample/cut-off (S/CO) ratio.

METHODS

One hundred and ninety patients who were anti-HCV positive were enrolled, from November 1998 to January 2002 in Kyung Hee University Hospital. RT-PCR was performed to confirm HCV infection.

RESULTS

One hundred and seven patients were RT-PCR positive (56.3% positive predictability). The positive predictability changed with the S/CO ratio: 17.9% in cases below 6, 58.3% between 6 and 50, 78.6% between 51 and 75, and 60% over 75. Those with the S/CO ratio more than 6 showed significantly higher predictability, but it did not increase further when the ratio got higher. Factors predicting HCV infection were the presence of liver cirrhosis (OR 5.5, p=0.000), hepatocellular carcinoma (OR 11.67, p=0.004), liver diseases (OR 2.99 p=0.001), and increase of AST (OR 2.49, p=0.002), ALT (OR 2.32, p=0.005), alpha-FP (OR 3.49, p=0.040), and the S/CO ratio of more than 6 (OR 7.82, p=0.000). However, liver cirrhosis was the sole factor in multivariate analysis (OR 8.32, p=0.02).

CONCLUSIONS

The positive predictability of the third generation anti-HCV test was 56.3% with a significant difference between those with the S/CO ratio below 6 (18%) and above 6 (63%). In liver cirrhosis, positive predictability of anti-HCV test was relatively high as 85%.