Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Hong Kong Med J ; 21(1): 23-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25634931

ABSTRACT

OBJECTIVE: To determine factors predicting complications caused by colonoscopy. DESIGN: Prospective cohort study. SETTING: A private hospital in Hong Kong. PATIENTS: All patients undergoing colonoscopy in the Endoscopy Centre of the Hong Kong Sanatorium & Hospital from 1 June 2011 to 31 May 2012 were included. Immediate complications were those that were recorded by nurses during and up to the day after the examination, while delayed complications were gathered 30 days after the procedure by way of consented telephone interview by trained student nurses. Data were presented as frequency and percentage for categorical variables. Logistic regression was used to fit models for immediate and systemic complications with related factors. RESULTS: A total of 6196 patients (mean age, 53.7 years; standard deviation, 12.7 years; 3143 women) were enrolled and 3657 telephone interviews were completed. The incidence of immediate complications was 15.3 per 1000 procedures (95% confidence interval, 12.3-18.4); 50.5% were colonoscopy-related, including one perforation and other minor presentations. Being female (odds ratioadjusted=1.6), use of monitored anaesthetic care (odds ratioadjusted=1.8), inadequate bowel preparation (odds ratioadjusted=3.5), and incomplete colonoscopy (odds ratioadjusted=4.5) were predictors of risk for all immediate complications (all predictors had P<0.05 by logistic regression). The incidence of delayed complications was 1.6 per 1000 procedures (95% confidence interval, 0.3-3.0), which comprised five post-polypectomy bleeds and one post-polypectomy inflammation. The overall incidence of complications was 17.8 per 1000 procedures (95% confidence interval, 13.5-22.1). The incidences of complications were among the lower ranges across studies worldwide. CONCLUSION: Inadequate bowel preparation and incomplete colonoscopy were identified as factors that increased the risk for colonoscopy-related complications. Colonoscopy-related complications occurred as often as systemic complications, showing the importance of monitoring.


Subject(s)
Colonoscopy/adverse effects , Adult , Aged , Cathartics/administration & dosage , Consciousness Monitors/statistics & numerical data , Female , Humans , Intestinal Perforation/etiology , Logistic Models , Male , Middle Aged , Odds Ratio , Prospective Studies , Risk , Sex Factors , Surveys and Questionnaires
2.
Hong Kong Med J ; 19(1): 61-8, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23378357

ABSTRACT

UNLABELLED: OBJECTIVE; With the increasing use of biologics in patients with inflammatory bowel disease, the Hong Kong IBD Society developed a set of consensus statements intended to serve as local recommendations for clinicians about the appropriate use of biologics for treating inflammatory bowel disease. PARTICIPANTS: The consensus meeting was held on 9 July 2011 in Hong Kong. Draft consensus statements were developed by core members of the Hong Kong IBD Society, including local gastroenterologists and colorectal surgeons experienced in managing patients with inflammatory bowel disease. EVIDENCE: Published literature and conference proceedings on the use of biologics in management of inflammatory bowel disease, and guidelines and consensus issued by different international and regional societies on recommendations for biologics in inflammatory bowel disease patients were reviewed. CONSENSUS PROCESS: Four core members of the consensus group drafted 19 consensus statements through the modified Delphi process. The statements were first circulated among a clinical expert panel of 15 members for review and comments, and were finalised at the consensus meeting through a voting session. A consensus statement was accepted if at least 80% of the participants voted "accepted completely or "accepted with some reservation". CONCLUSIONS: Nineteen consensus statements about inflammatory bowel disease were generated by the clinical expert panel meeting. The statements were divided into four parts which covered: (1) epidemiology of the disease in Hong Kong; (2) treatment of the disease with biologics; (3) screening and contra-indications pertaining to biologics; and (4) patient monitoring after use of biologics. The current statements are the first to describe the appropriate use of biologics in the management of inflammatory bowel disease in Hong Kong, with an aim to provide guidance for local clinical practice.


Subject(s)
Immunologic Factors/therapeutic use , Inflammatory Bowel Diseases/drug therapy , Practice Patterns, Physicians' , Delphi Technique , Drug Monitoring/methods , Hong Kong , Humans , Immunologic Factors/administration & dosage , Immunologic Factors/adverse effects , Inflammatory Bowel Diseases/physiopathology
3.
Hong Kong Med J ; 18(5): 388-94, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23018066

ABSTRACT

OBJECTIVES. Although Picolax (sodium picosulphate and magnesium citrate) has been widely documented for use in bowel preparation, there is limited literature on its efficacy in the treatment of constipation. Refractory constipation is a more difficult situation with limited treatment options available. The primary objective of this study was to investigate the efficacy of Picolax in the treatment of refractory constipation. DESIGN. Prospective single-centre cohort study. SETTING. The Gastroenterology and Hepatology Centre of a major private hospital in Hong Kong. PATIENTS. Patients aged 18 years or more with chronic constipation refractory to tegaserod or polyethylene glycol and attending the centre in the period of July 2009 to June 2010. RESULTS. A total of 20 patients completed this 6-week single-centre study, with a 2-week baseline assessment and 4-week treatment period. Complete data sets were available for analysis from 17 of these patients. The mean (standard deviation) age of the cohort was 50 (9) years, of which 94% were female. Treatment consisted of half-a-sachet of Picolax taken orally on alternate days, 3 times a week. Patients were required to fill in daily and weekly diary entries of their bowel habit. The mean (standard deviation) number of weekly complete spontaneous bowel movements increased from 0.5 (0.9) to 2.4 (2.6) times per week (P=0.02) after initiation of the treatment, which was a clinically and statistically significant difference; with a mean change of +1.9 (95% confidence interval, 0.3 to 3.4) per week. As a secondary endpoint, 11 patients recorded the use of rescue medication before and after the 4-week treatment. The ratio of patients who took rescue medication decreased significantly from 73% (n=8) to 0% (n=0) [P=0.008]. The mean reduction in the frequency of resorting to rescue medication was 2.6 times (95% confidence interval, -4.2 to -1.1) per week. CONCLUSIONS. Picolax improved the number of complete spontaneous bowel movements and significantly reduced resorting to rescue medication. This formulation could therefore be considered as a treatment option in patients with chronic constipation who are refractory to conventional treatment regimens.


Subject(s)
Cathartics/therapeutic use , Citric Acid/therapeutic use , Constipation/drug therapy , Organometallic Compounds/therapeutic use , Picolines/therapeutic use , Adult , Cathartics/administration & dosage , Chronic Disease , Citrates , Citric Acid/administration & dosage , Cohort Studies , Drug Combinations , Female , Follow-Up Studies , Humans , Indoles/therapeutic use , Male , Middle Aged , Organometallic Compounds/administration & dosage , Picolines/administration & dosage , Pilot Projects , Polyethylene Glycols/therapeutic use , Prospective Studies , Treatment Outcome
4.
Ann Acad Med Singap ; 39(3): 185-90, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20372753

ABSTRACT

INTRODUCTION: The angiographic findings and prognosis of patients with complete atrioventricular block (AVB) complicating acute inferior myocardial infarction (MI) remain unclear. MATERIALS AND METHODS: The clinical and angiographic findings of 70 consecutive patients with complete AVB were compared with those of 319 patients with inferior MI without AVB (control group) admitted within the same study period. RESULTS: Patients with complete AVB were older (68 +/- 12 vs 63 +/- 13 years; P = 0.004) and clustered with clinical features indicative of larger infarct size, such as right ventricular infarction, cardiogenic shock, or low left ventricular ejection fraction (LVEF). The onset of the complete AVB was observed within 24 hours in 62 (88.6%), preceded by second-degree AVB in 26 (37.1%) and the escape QRS complex was wide in 8 (11.4%) patients. In patients with complete AVB, a dominant right coronary artery occlusion was found in >95% of cases and in-hospital mortality was increased (27.1% vs 10.7%; P = 0.000), especially in those with widen QRS escape rhythm (75.0%). Reperfusion therapy had a positive impact on the natural course of complete AVB. CONCLUSIONS: Complete AVB in acute inferior MI was associated with advanced age and larger infarct size. Complete AVB was virtually always caused by dominant right coronary artery occlusion. The in-hospital mortality was significantly higher, but improved by reperfusion therapy. No permanent pacemaker is performed at a mean follow-up of 47 months.


Subject(s)
Atrioventricular Block/complications , Atrioventricular Block/diagnostic imaging , Coronary Angiography , Inferior Wall Myocardial Infarction/complications , Inferior Wall Myocardial Infarction/diagnostic imaging , Age Factors , Aged , Aged, 80 and over , Atrioventricular Block/mortality , Electrocardiography , Female , Hong Kong/epidemiology , Hospital Mortality , Humans , Inferior Wall Myocardial Infarction/mortality , Kaplan-Meier Estimate , Male , Middle Aged
5.
J Gastroenterol Hepatol ; 24(5): 896-9, 2009 May.
Article in English | MEDLINE | ID: mdl-19646018

ABSTRACT

BACKGROUND AND METHODS: Upper endoscopy records from 1998 to 2003 were reviewed. The demographic data, endoscopic diagnosis, results of rapid urease test and the absence or presence of intestinal metaplasia (IM) in histology were reviewed, to evaluate the prevalence of IM and Helicobacter pylori (Hp) infection over time in Hong Kong. RESULTS: Among 1805 endoscopies performed, 1751 had both rapid urease test and histology available. A significant drop in the prevalence of duodenal ulcers from 17.9% in 1998 to 9.8% in 2003 was found (P = 0.015). Prevalence of IM was 13.9%, 5.9% and 9.4% in Hp positive, Hp negative and overall respectively (P < 0.05). The prevalence of IM increased with age, and the patterns were similar amongst subjects in 1998-2000 and those in 2001-2003. There was progressive decrease in Hp prevalence from 58% in 1998 to 40% in 2001 (P = 0.014), but no further decrease was seen in 2002-3. There was no corresponding decrease in IM prevalence. Instead IM prevalence in 2002-2003 was significantly higher than the prevalence in previous few years (P = 0.04). CONCLUSION: The prevalence of IM did not change in the period from 1998 to 2003 despite a drop in the prevalence of Hp infection since 1994.


Subject(s)
Esophageal Neoplasms/epidemiology , Helicobacter Infections/epidemiology , Helicobacter pylori/pathogenicity , Precancerous Conditions/epidemiology , Stomach Neoplasms/epidemiology , Stomach Ulcer/epidemiology , Adolescent , Adult , Age Distribution , Age Factors , Aged , Aged, 80 and over , Breath Tests , Duodenal Ulcer/epidemiology , Duodenal Ulcer/microbiology , Duodenal Ulcer/pathology , Endoscopy, Gastrointestinal , Esophageal Neoplasms/microbiology , Esophageal Neoplasms/pathology , Esophagoscopy , Female , Helicobacter Infections/microbiology , Helicobacter Infections/pathology , Hong Kong/epidemiology , Humans , Male , Metaplasia , Middle Aged , Precancerous Conditions/microbiology , Precancerous Conditions/pathology , Prevalence , Sex Distribution , Sex Factors , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Stomach Ulcer/microbiology , Stomach Ulcer/pathology , Time Factors , Young Adult
6.
Cancer ; 115(23): 5441-9, 2009 Dec 01.
Article in English | MEDLINE | ID: mdl-19685530

ABSTRACT

BACKGROUND: This study aimed to determine the potential diagnostic value of migration-inhibitory factor (MIF) for gastric cancer in patients presenting with dyspepsia and its prognostic value for gastric cancer. METHODS: A cohort of 97 patients with histologically confirmed gastric adenocarcinoma and 222 patients with dyspepsia were recruited. Enzyme-linked immunosorbent assay was used to measure serum MIF and carcinoembryonic antigen (CEA). RESULTS: The serum MIF concentrations were 6554.0 +/- 204.1 pg/mL and 1453.7 +/- 79.9 pg/mL, respectively, in gastric cancer patients and dyspeptic patients (P < .001). Serum MIF levels increased with the advancing gastric pathologies (P < .001). With the cutoff value of 3230 pg/mL, serum MIF had sensitivity, specificity, and accuracy of 83.5%, 92.3%, and 89.7%, respectively, in diagnosing gastric cancer, whereas the rates were 60.8%, 83.3%, and 76.5%, respectively, for serum CEA. Gastric cancer patients with serum MIF levels above 6600 pg/mL had a lower 5-year survival rate than those with serum MIF level below that level (P = .012). Higher serum CEA levels were also associated with poor survival. The prediction for 5-year survival was even better (P = .0001), using a combination of serum MIF and CEA. CONCLUSIONS: Serum MIF level, which correlates with gastric MIF expression, is a better molecular marker than CEA in diagnosing gastric cancer in patients presenting with dyspepsia. A combination of serum MIF and CEA predicts 5-year survival better than the individual test.


Subject(s)
Biomarkers, Tumor/blood , Macrophage Migration-Inhibitory Factors/blood , Stomach Neoplasms/blood , Aged , Dyspepsia/pathology , Female , Humans , Male , Middle Aged , Prognosis , Stomach Neoplasms/diagnosis , Stomach Neoplasms/mortality
7.
J Clin Gastroenterol ; 43(1): 13-8, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18698264

ABSTRACT

BACKGROUND: Chest pain is common and data regarding noncardiac chest pain (NCCP) in Asia are lacking. AIM: To determine the differences in clinical presentations, psychologic impact, and quality of life between patients with NCCP and cardiac chest pain (CCP), and to identify any factors that impacted on these patients. METHODS: Consecutive patients undergoing coronary angiography for the evaluation of chest pain were recruited in Hong Kong and Wuhan, China. One hundred and forty patients with abnormal and 141 patients with normal angiography were included in the study. The validated gastroesophageal reflux disease questionnaire, the Hospital Anxiety-Depression Scale, and the 12-item Short Form Health Survey (SF-12) were used for assessment. RESULTS: NCCP patients reported similar days-off work and impairment of their social life compared with those with CCP. No difference was found in the anxiety and depression scores between the 2 groups. NCCP patients with reflux symptoms had higher anxiety score (7.19 vs. 5.74, P=0.044), reported more interruption of their social life (26% vs. 5%, P<0.0001), and had taken more sick leaves (17% vs. 5%, P=0.018) compared with those without gastroesophageal reflux disease. CONCLUSIONS: The quality of life and psychologic impact of patients with NCCP were as significant as those with CCP. NCCP patients with reflux symptoms were more anxious and were impaired in their productivity and social life.


Subject(s)
Chest Pain/psychology , Gastroesophageal Reflux/psychology , Quality of Life , Absenteeism , Adult , Aged , Chest Pain/diagnosis , Chest Pain/etiology , China/epidemiology , Coronary Angiography , Efficiency , Female , Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/physiopathology , Hong Kong/epidemiology , Humans , Male , Middle Aged , Prospective Studies , Psychiatric Status Rating Scales , Sick Leave , Social Behavior , Surveys and Questionnaires
8.
Helicobacter ; 13(1): 20-9, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18205662

ABSTRACT

BACKGROUND: Helicobacter pylori infection is a major cause of gastritis and gastric carcinoma. Aspirin has anti-inflammatory and antineoplastic activity. The aim of the present study was to determine the effects of aspirin on H. pylori-induced gastritis and the development of heterotopic proliferative glands. METHODS: H. pylori strain SS1 was inoculated into the stomachs of Mongolian gerbils. Two weeks after inoculation, the animals were fed with the powder diets containing 0 p.p.m. (n = 10), 150 p.p.m. (n = 10), or 500 p.p.m. (n = 10) aspirin. Mongolian gerbils were killed after 36 weeks of infection. Uninfected Mongolian gerbils (n = 10) were used as controls. Histologic changes, epithelial cell proliferation and apoptosis, and prostaglandin E(2) (PGE(2)) levels of gastric tissue were determined. RESULTS: H. pylori infection induced gastric inflammation. Administration of aspirin did not change H. pylori-induced gastritis, but alleviated H. pylori-induced hyperplasia and the development of heterotopic proliferative glands. Administration of aspirin accelerated H. pylori-associated apoptosis but decreased H. pylori-associated cell proliferation. In addition, the increased gastric PGE(2) levels due to H. pylori infection were suppressed by treatment with aspirin, especially at the dose of 500 p.p.m. CONCLUSIONS: Aspirin alleviates H. pylori-induced hyperplasia and the development of heterotopic proliferative glands. Moreover, aspirin increases H. pylori-induced apoptosis. We demonstrated the antineoplastic activities of aspirin in H. pylori-related gastric carcinogenesis.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Aspirin/pharmacology , Choristoma/prevention & control , Gastric Mucosa/drug effects , Helicobacter Infections/pathology , Helicobacter pylori/physiology , Inflammation/prevention & control , Animals , Anti-Inflammatory Agents/administration & dosage , Apoptosis , Aspirin/administration & dosage , Choristoma/pathology , Dinoprostone/analysis , Epithelial Cells/pathology , Gastric Mucosa/chemistry , Gastric Mucosa/pathology , Gerbillinae , Helicobacter Infections/microbiology , Hyperplasia/prevention & control , Inflammation/pathology , Male
9.
Digestion ; 75(2-3): 128-34, 2007.
Article in English | MEDLINE | ID: mdl-17671381

ABSTRACT

BACKGROUND: Previous studies suggested that Chinese have a milder spectrum of gastro-oesophageal reflux disease and a lower dose of proton pump inhibitors (PPI) is sufficient for the control of symptoms as compared with the Western population. AIMS: To determine if 8 weeks of esomeprazole 20 mg daily would be adequate for both symptom resolution and oesophagitis healing in Chinese patients and the predictive factors for the response. METHODS: 66 patients with oesophagitis were included. Oesophagitis severity was graded by Los Angeles (LA) classification. 61 patients underwent 24-hour ambulatory pH study at baseline. All were given esomeprazole 20 mg daily for 8 weeks. Symptom response and healing of oesophagitis was assessed at the end of the treatment period. RESULTS: 75.8% of the patients had complete reflux symptom resolution but only 48% had complete healing of the oesophagitis at endoscopy after 8 weeks of treatment. LA classification grading at baseline endoscopy (p < 0.0001) and total number acid reflux episodes on 24-hour pH monitoring prior to treatment (p = 0.007) were both good predictors of oesophagitis healing but not for symptom resolution. CONCLUSIONS: Our results suggested that 8 weeks of lower dose PPI is not sufficient for oesophagitis healing. Symptom resolution with PPI does not predict oesophagitis healing in Chinese.


Subject(s)
Anti-Ulcer Agents/therapeutic use , Esomeprazole/therapeutic use , Esophagitis/drug therapy , Esophagitis/ethnology , Chi-Square Distribution , China , Esophagoscopy , Female , Gastric Acidity Determination , Humans , Hydrogen-Ion Concentration , Logistic Models , Male , Manometry , Middle Aged , Risk Factors , Severity of Illness Index , Surveys and Questionnaires , Treatment Outcome
10.
Am J Gastroenterol ; 102(1): 149-52, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17037990

ABSTRACT

OBJECTIVES: Clinical observation showed that there is family aggregation in constipated subjects, but formal data are lacking. This prompted us to conduct a formal family study in constipated subjects. METHODS: Constipated subjects (probands) were identified according to the Rome II and Chinese constipation questionnaire criteria, healthy subjects were chosen as controls. Living first-degree relatives (parents, siblings, and children) and spouses (as internal controls) from both groups were identified. The questionnaire on Rome II criteria was given to the relatives either through the index subjects or by mail. The questionnaire was received by mailing back or through the index subjects. Any nonresponders were chased. RESULTS: There were 132 probands with constipation and 114 controls. The Rome II questionnaire was sent to a total of 677 relatives of the probands and 591 of the controls. Relatives were comparable in mean age, sex distribution, family size, and marital status in the two groups. Constipation prevalence was 16.4% in probands' relatives versus 9.1% in controls' relatives, i.e., 13% in the relatives from both proband and controls. Among the constipated relatives, 6.3%versus 9.3% of the relatives were spouses of the probands and controls (P = 0.5). Subjects with more family members having constipation will have higher risk of constipation: OR 2.02, CI 1.14-3.65, P = 0.0177 for at least one family member; OR 3.99, CI 1.86-9.23, P = 0.0006 for at least two family members. CONCLUSIONS: Familial aggregation of constipation occurs, supporting a genetic or intrafamilial environment component.


Subject(s)
Constipation/genetics , Case-Control Studies , Chi-Square Distribution , Constipation/epidemiology , Female , Gastrointestinal Transit , Genetic Predisposition to Disease , Hong Kong/epidemiology , Humans , Male , Middle Aged , Prevalence , Surveys and Questionnaires
11.
World J Gastroenterol ; 12(31): 5010-6, 2006 Aug 21.
Article in English | MEDLINE | ID: mdl-16937497

ABSTRACT

AIM: To investigate the optimal strategy to treat dyspeptic patients in primary care. METHODS: Dyspeptic patients presenting to primary care outpatient clinics were randomly assigned to: (1) empirical endoscopy, (2) H pylori test-and-treat, and (3) empirical prokinetic treatment with cisapride. Early endoscopy was arranged if patients remained symptomatic after 2 wk. Symptom severity, quality-of-life (SF-36) as well as patient preference and satisfaction were assessed. All patients underwent endoscopy by wk 6. Patients were followed up for one year. RESULTS: Two hundred and thirty four patients were recruited (163 female, mean age 49). 46% were H pylori positive. 26% of H pylori tested and 25% of empirical prokinetic patients showed no improvement at wk 2 follow-up and needed early endoscopy. 15% of patients receiving empirical cisapride responded well to treatment but peptic ulcer was the final diagnosis. Symptom resolution and quality-of-life were similar among the groups. Costs for the three strategies were HK dollar 4343, dollar 1771 and dollar 1750 per patient. 66% of the patients preferred to have early endoscopy. CONCLUSION: The three strategies are equally effective. Empirical prokinetic treatment was the least expensive but peptic ulcers may be missed with this treatment. The H pylori test-and-treat was the most cost-effective option.


Subject(s)
Dyspepsia/diagnosis , Endoscopy/methods , Helicobacter Infections/diagnosis , Helicobacter pylori/metabolism , Primary Health Care/methods , Adolescent , Adult , Aged , Cost-Benefit Analysis , Endoscopy/economics , Female , Humans , Male , Middle Aged
12.
Digestion ; 73(2-3): 84-8, 2006.
Article in English | MEDLINE | ID: mdl-16788289

ABSTRACT

BACKGROUND: The incidence of colorectal cancer (CRC) in Hong Kong is rising. The trend of colonoscopy demand is uncertain. AIM: To investigate colonoscopy demand and practice in a Hong Kong regional hospital over the past nine years. METHODS: Colonoscopy data from 1st January 1997 to 31st August 2005 were retrieved and divided into two equal periods for comparison. Colonoscopy practice and findings between the two periods were compared. RESULTS: There was no change in the number of endoscopists and colonoscopy sessions in the two periods. The number of colonoscopy done in the two periods was 2,681 and 2,871, respectively. The indications for screening of CRC/polyp (9.3 vs. 24.7%, p < 0.0001) and surveillance of CRC/polyp (4.7 vs. 10.9%, p < 0.0001) were increased, but decreased for diarrhea (18 vs. 10.2%, p < 0.0001) and per rectal bleeding (19 vs. 8.1%, p < 0.0001). The waiting time was lengthened from 2 to 4 weeks (p < 0.0001). The percentage of colonic adenomas (19.9 vs. 27.2%, p < 0.0001) was increased. A right-shift was observed in both CRC (37 vs. 50%, p = 0.018) and adenoma (21.6 vs. 38.1%, p < 0.0001). CONCLUSION: The number of colonoscopies performed was governed by capacity partly through lengthening of waiting time to cope with demand. Ways to improve capacity for colonoscopies is needed.


Subject(s)
Colonoscopy/statistics & numerical data , Colorectal Neoplasms/epidemiology , Mass Screening , Adolescent , Adult , Aged , Aged, 80 and over , Chi-Square Distribution , Female , Health Services Needs and Demand , Hong Kong/epidemiology , Humans , Incidence , Male , Middle Aged , Waiting Lists
13.
Digestion ; 73(2-3): 75-83, 2006.
Article in English | MEDLINE | ID: mdl-16641552

ABSTRACT

BACKGROUND/AIM: Inhibition of cyclooxygenase-2 has been proposed to be a potential mechanism for the chemoprevention of gastrointestinal tumors by nonsteroidal anti-inflammatory drugs. This study investigates the mechanisms by which the cyclooxygenase-2 inhibitor SC236 induces apoptosis of gastric cancer cell lines and its downstream signaling pathway. METHODS: Two gastric cancer cell lines, AGS and MKN28, were treated with SC236 and assessed for cell growth and apoptosis. The involvement of mitogen-activated protein kinase and Akt kinase/protein kinase B (Akt/PKB) pathways and their downstream signalings were studied in the AGS cell line. RESULTS: SC236 treatment induced apoptosis in gastric cancer cells and caused activation of p38 and stress-activated protein kinase/jun kinase, but down-regulated Akt/PKB. The specific p38 inhibitor SB203580 and the dominant-negative stress-activated protein kinase/jun kinase both failed, while the constitutively active form of Akt/PKB was able to block SC236-induced apoptosis. SC236-induced apoptosis was coupled with release of cytochrome c and activation of caspases. CONCLUSION: One of the pathways involved in SC-236-induced apoptosis in gastric cancer cells is through downregulation of Akt and then release of cytochrome c.


Subject(s)
Adenocarcinoma/pathology , Apoptosis/drug effects , Cyclooxygenase 2 Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Pyrazoles/pharmacology , Stomach Neoplasms/pathology , Sulfonamides/pharmacology , Acridine Orange , Blotting, Western , Caspases/metabolism , Cytochromes c/metabolism , Down-Regulation , Enzyme Activation , Humans , Mitogen-Activated Protein Kinases/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Transfection , Tumor Cells, Cultured
14.
J Infect Dis ; 193(7): 1037-46, 2006 Apr 01.
Article in English | MEDLINE | ID: mdl-16518767

ABSTRACT

BACKGROUND: Cyclooxygenases (COXs) play important roles in inflammation and carcinogenesis. The present study aimed to determine the effects of COX-1 and COX-2 gene disruption on Helicobacter pylori-induced gastric inflammation. METHODS: Wild-type (WT), COX-1 and COX-2 heterozygous (COX-1+/- and COX-2+/-), and homozygous COX-deficient (COX-1-/- and COX-2-/-) mice were inoculated with H. pylori strain TN2 and killed after 24 weeks of infection. Uninfected WT and COX-deficient mice were used as controls. Levels of gastric mucosal inflammation, epithelial cell proliferation and apoptosis, and cytokine expression were determined. RESULTS: COX deficiency facilitated H. pylori-induced gastritis. In the presence of H. pylori infection, apoptosis was increased in both WT and COX-deficient mice, whereas cell proliferation was increased in WT and COX-1-deficient, but not in COX-2-deficient, mice. Tumor necrosis factor (TNF)-alpha and interleukin-10 mRNA expression was elevated in H. pylori-infected mice, but only TNF-alpha mRNA expression was further increased by COX deficiency. Prostaglandin E2 levels were increased in infected WT and COX-2-deficient mice but were at very low levels in infected COX-1-deficient mice. Leukotriene (LT) B4 and LTC4 levels were increased to a similar extent in infected WT and COX-deficient mice. CONCLUSIONS: COX deficiency enhances H. pylori-induced gastritis, probably via TNF-alpha expression. COX-2, but not COX-1, deficiency suppresses H. pylori-induced cell proliferation.


Subject(s)
Cyclooxygenase 1/physiology , Cyclooxygenase 2/physiology , Gastric Mucosa/pathology , Gastritis/enzymology , Gastritis/microbiology , Helicobacter Infections/enzymology , Helicobacter pylori/pathogenicity , Animals , Apoptosis , Cell Proliferation , Cyclooxygenase 1/deficiency , Cyclooxygenase 1/genetics , Cyclooxygenase 2/deficiency , Cyclooxygenase 2/genetics , Dinoprostone/analysis , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Gastric Mucosa/immunology , Gastric Mucosa/microbiology , Gastritis/immunology , Gastritis/pathology , Gene Expression Regulation , Helicobacter Infections/immunology , Helicobacter Infections/microbiology , Helicobacter Infections/pathology , Interleukin-10/genetics , Leukotriene B4/analysis , Leukotriene C4/analysis , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/analysis , Tumor Necrosis Factor-alpha/genetics
15.
Gastroenterology ; 130(3): 747-58, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16530516

ABSTRACT

BACKGROUND & AIMS: X-linked inhibitor of apoptosis protein (XIAP)-associated factor 1 (XAF1) is a novel tumor suppressor and interferon (IFN)-stimulated gene. All-trans retinoic acid (ATRA) exerts an antiproliferative effect on tumor cells through up-regulation of IFN regulatory factor 1 (IRF-1) and the downstream IFN-stimulated genes. The aim of this study was to determine the effect and mechanism of ATRA on XAF1 expression and the role of XAF1 in ATRA-induced growth inhibition in colon cancer. METHODS: Gene expression is detected by reverse-transcription polymerase chain reaction and immunoblotting. The transcription activity of XAF1 promoter is examined by luciferase reporter assay. The activity of IFN regulatory factor binding element (IRF-E) is assessed by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Cell growth is evaluated by both in vitro and in vivo in nude mice xenografts. RESULTS: IFN-alfa stimulates XAF1 promoter activity in the colon cancer cells Lovo and SW1116 dose-dependently. An IRF-1 binding element (IRF-E-XAF1) is found in the -30 to -38 nucleotide region upstream of the ATG initiator codon of the XAF1 gene. Site-directed mutagenesis of IRF-E-XAF1 abrogates native and IFN-induced promoter activity and binding capacity. ATRA induces XAF1 expression both in vitro and in vivo through interaction with IRF-E-XAF1. Overexpression of XAF1 increases cell susceptibility to ATRA-induced growth suppression both in vitro and in vivo. Furthermore, the effect of ATRA on XAF1 expression is independent of the promoter methylation and the subcellular distribution of XIAP. CONCLUSIONS: XAF1 participates in ATRA-induced growth suppression through IRF-1-mediated transcriptional regulation.


Subject(s)
Colonic Neoplasms/metabolism , Interferon Regulatory Factor-1/physiology , Neoplasm Proteins/genetics , Tretinoin/pharmacology , Adaptor Proteins, Signal Transducing , Animals , Apoptosis Regulatory Proteins , Cell Line, Tumor , Colonic Neoplasms/drug therapy , CpG Islands , DNA Methylation , Gene Expression Regulation/drug effects , Humans , Intracellular Signaling Peptides and Proteins , Mice , Mutagenesis, Site-Directed , Neoplasm Proteins/physiology , Promoter Regions, Genetic , Transcription Initiation Site
16.
Cancer ; 106(6): 1243-9, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16444744

ABSTRACT

BACKGROUND: Telomerase activation, which is observed in most human cancers, plays an important role in carcinogenesis. Human telomerase reverse transcriptase (hTERT) is a subunit of telomerase that is essential for telomerase activity. The aim of the study was to investigate whether nonsteroidal antiinflammatory drugs (NSAIDs) inhibit telomerase activity and hTERT. METHODS: Four colon carcinoma cell lines, HT-29, COLO205, CRL-2134, and SW1116, were used in the experiments. Polymerase chain reaction-based telomeric repeat amplification (TRAP) enzyme-linked immunosorbent assay (ELISA) was used to measure telomerase activity in the cells after treatment with aspirin, indomethacin, or SC-236 (a specific cyclooxygenase-2 [COX-2] inhibitor). Expression of hTERT mRNA and protein was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively. The dual luciferase reporter assay was performed to identify the potential cis-response elements to NSAIDs in the promoter region of hTERT. RESULTS: Aspirin, indomethacin, and SC-236 inhibited telomerase activity in HT-29, COLO205, and CRL-2134 cell lines, but not in the SW1116 cell line. NSAIDs inhibited hTERT mRNA and protein expression through suppression of hTERT transcriptional activity. The hTERT promoter fragment -145 to -330 basepairs (bp) upstream of the ATG starting site was sufficient to respond to the NSAID-induced inhibitory effect and the inhibition was COX-2-independent. CONCLUSION: NSAIDs inhibit telomerase activity at hTERT transcriptional, mRNA, and protein levels in colon carcinoma cells. The hTERT promoter fragment -145 to -330 bp may be the cis-response element to NSAIDs.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aspirin/pharmacology , Colonic Neoplasms/drug therapy , DNA-Binding Proteins/antagonists & inhibitors , Indomethacin/pharmacology , Pyrazoles/pharmacology , Sulfonamides/pharmacology , Telomerase/antagonists & inhibitors , Adenocarcinoma/drug therapy , Adenocarcinoma/enzymology , Adenocarcinoma/genetics , Blotting, Western , Colonic Neoplasms/enzymology , Colonic Neoplasms/genetics , Cyclooxygenase 2/chemistry , Cyclooxygenase 2/metabolism , Cyclooxygenase Inhibitors/pharmacology , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Neoplastic , Humans , Luciferases/metabolism , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm , Response Elements , Telomerase/genetics , Telomerase/metabolism , Transcription, Genetic , Tumor Cells, Cultured
17.
Cancer Lett ; 241(2): 268-74, 2006 Sep 28.
Article in English | MEDLINE | ID: mdl-16337741

ABSTRACT

The c-Jun NH(2)-terminal kinase (JNK) is activated in several tumor cell lines. The aim of this study was to determine the effects of SP-600125, a specific JNK inhibitor, on the viability, apoptosis, cell cycle distribution of gastrointestinal cancer cells, and the potential anti-tumor mechanisms. Three gastric cancer cell lines, AGS, BCG-823 and MKN-45, and three colorectal cancer cell lines, SW1116, COLO205 and HT-29, were used. Cells were treated with SP-600125, and cell viability, apoptosis and cell cycle distribution, caspase-3 activity, expression of JNK and apoptosis related proteins were detected. SP-600125 inhibited cell proliferation by 10-80% for the different cell lines, and increased apoptosis by 1.5-4.5 folds for COLO205, BCG-823, MKN-45, AGS cells. Caspase-8 and caspase-3 were involved in the induction of apoptosis. SP-600125 caused G2/M cell cycle arrest and elevation of cyclin B1 and p27(kip). The differential response in cells to SP-600125 was associated with the basal level of phosphorylated JNK2. It is concluded that SP-600125 inhibits proliferation, induces apoptosis and causes cell cycle arrest in gastrointestinal cancer cells, indicating that JNK inhibitors have an anti-tumor effect and are potential therapeutic agents for cancers.


Subject(s)
Anthracenes/pharmacology , Apoptosis/drug effects , Cell Division/drug effects , Enzyme Inhibitors/pharmacology , G2 Phase/drug effects , Gastrointestinal Neoplasms/drug therapy , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , Caspases/metabolism , Cell Proliferation/drug effects , Humans , JNK Mitogen-Activated Protein Kinases/genetics , JNK Mitogen-Activated Protein Kinases/metabolism , RNA, Messenger/metabolism , Tumor Cells, Cultured
18.
J Gastroenterol Hepatol ; 20(6): 935-40, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15946144

ABSTRACT

BACKGROUND: Rabeprazole in combination with amoxicillin and metronidazole (RAM) has been shown to be an effective second-line treatment of Helicobacter pylori infection. The effects were compared of 7-day low-dose and high dose rabeprazole in RAM for the primary treatment of H. pylori infection in Chinese patients. METHODS: Helicobacter pylori-positive dyspeptic patients were randomized to receive either (i) rabeprazole 10 mg, amoxicillin 1000 mg and metronidazole 400 mg (RAM-10) or (ii) high-dose rabeprazole 20 mg, amoxicillin 1000 mg and metronidazole 400 mg (RAM-20), each given twice daily for 7 days. Helicobacter pylori eradication was confirmed by (13)c-urea breath test 5 weeks after stopping medications. side-effects of treatments were documented. RESULTS: A total of 120 patients were eligible for analysis. By intention-to-treat and per-protocol analysis, the eradication rates were 83% and 86% in the RAM-10 group and 75% and 76% in the RAM-20 group, respectively (P = 0.26 and P = 0.17). Both regimens were well-tolerated and compliance was >98% in both groups. CONCLUSIONS: Low-dose rabeprazole in combination with amoxicillin and metronidazole is an effective, economical and well-tolerated therapy for the treatment of H. pylori infection in Chinese population.


Subject(s)
Amoxicillin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Benzimidazoles/therapeutic use , Enzyme Inhibitors/therapeutic use , Helicobacter Infections/drug therapy , Metronidazole/therapeutic use , Omeprazole/analogs & derivatives , 2-Pyridinylmethylsulfinylbenzimidazoles , Adolescent , Adult , Aged , Aged, 80 and over , Amoxicillin/administration & dosage , Anti-Bacterial Agents/administration & dosage , Benzimidazoles/administration & dosage , Biopsy , Dose-Response Relationship, Drug , Drug Therapy, Combination , Dyspepsia/drug therapy , Dyspepsia/epidemiology , Dyspepsia/etiology , Endoscopy, Gastrointestinal , Enzyme Inhibitors/administration & dosage , Female , Helicobacter Infections/complications , Helicobacter Infections/epidemiology , Helicobacter pylori/isolation & purification , Humans , Male , Metronidazole/administration & dosage , Middle Aged , Omeprazole/administration & dosage , Omeprazole/therapeutic use , Prevalence , Proton-Translocating ATPases/antagonists & inhibitors , Pyloric Antrum/microbiology , Pyloric Antrum/pathology , Rabeprazole , Retrospective Studies , Treatment Outcome
19.
World J Gastroenterol ; 11(13): 1946-50, 2005 Apr 07.
Article in English | MEDLINE | ID: mdl-15800984

ABSTRACT

AIM: Helicobacter pylori (H pylori) is associated with increased gastric inflammatory and epithelial expression of macrophage migration inhibitory factor (MIF) and gastric epithelial cell proliferation. This study aimed at determining whether H pylori directly stimulates release of MIF in monocytes, whether the cag pathogenicity island (PAI) is involved for this function, and whether MIF stimulated by H pylori increases gastric epithelial cell proliferation in vitro. METHODS: A cytotoxic wild-type H pylori strain (TN2), its three isogenic mutants (TN2Deltacag, TN2DeltacagA and TN2DeltacagE) were co-cultured with cells of a human monocyte cell line, THP-1, for 24 h at different organism/cell ratios. MIF in the supernatants was measured by an ELISA. Cells of a human gastric cancer cell line, MKN45, were then co-cultured with the supernatants, with and without monoclonal anti-MIF antibody for 24 h. The cells were further incubated for 12 h after addition of 3H-thymidine, and the levels of incorporation of 3H-thymidine were measured with a liquid scintillation counter. RESULTS: The wild-type strain and the isogenic mutants, TN2DeltacagA and TN2 DeltacagE, increased MIF release at organism/cell ratios of 200/1 and 400/1, but not at the ratios of 50/1 and 100/1. However, the mutant TN2delta cag did not increase the release of MIF at any of the four ratios. 3H-thymidine readings for MKN-45 cells were significantly increased with supernatants derived from the wild-type strain and the mutants TN2DeltacagA and TN2DeltacagE, but not from the mutant TN2Deltacag. Moreover, in the presence of monoclonal anti-MIF antibody, the stimulatory effects of the wild-type strain on cell proliferation disappeared. CONCLUSION: H pylori stimulates MIF release in monocytes, likely through its cag PAI, but not related to cagA or cagE. H pylori-stimulated monocyte culture supernatant increases gastric cell proliferation, which is blocked by anti-MIF antibody, suggesting that MIF plays an important role in H pylori-induced gastric epithelial cell proliferation.


Subject(s)
Helicobacter Infections/pathology , Helicobacter pylori , Macrophage Migration-Inhibitory Factors/metabolism , Monocytes/microbiology , Stomach/microbiology , Antibodies, Monoclonal/pharmacology , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Cell Division/physiology , Cell Line , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Epithelial Cells/pathology , Helicobacter pylori/genetics , Humans , In Vitro Techniques , Macrophage Migration-Inhibitory Factors/immunology , Monocytes/cytology , Mutation , Stomach/pathology
20.
Gastroenterology ; 128(2): 361-75, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15685548

ABSTRACT

BACKGROUND AND AIMS: Reactivation of survivin expression is involved in carcinogenesis and angiogenesis in colon cancer. Previous in vitro studies showed that mutation of the cysteine residue at position 84 (Cys84Ala) of survivin generates a dominant-negative mutant that triggers mitotic catastrophe and apoptosis. We investigated the therapeutic effect of the adeno-associated virus (AAV)-mediated survivin mutant (Cys84Ala) on colon cancer. METHODS: Survivin mutant (Cys84Ala) (Sur-Mut(Cys84Ala)) was cloned into the AAV expression vector pAM/CAG-WPRE.poly(A) to generate recombinant AAV-Sur-Mut(Cys84Ala) virus. Cell proliferation, apoptosis, mitotic catastrophe, and tumor growth were measured in vitro and in vivo. RESULTS: Transduction of colon cancer cells with rAAV-Sur-Mut(Cys84Ala) inhibited cell proliferation and induced apoptosis and mitotic catastrophe in vitro. rAAV-Sur-Mut(Cys84Ala) sensitized colon cancer cells to chemotherapeutic drugs. Furthermore, expression of survivin mutant mediated by AAV inhibited tumorigenesis in colon cancer cells. Intratumoral injection of rAAV-Sur-Mut(Cys84Ala) significantly induced apoptosis and mitotic catastrophe and inhibited angiogenesis and tumor growth in a colon cancer xenograft model in vivo. No obvious cytotoxicity to other tissues was observed. More importantly, rAAV-Sur-Mut(Cys84Ala) expression strongly enhanced the antitumor activity of 5-Fluorouracil (5-FU), resulting in regression of established tumors. CONCLUSIONS: Our results showed that rAAV-Sur-Mut(Cys84Ala) induced apoptosis and mitotic catastrophe and inhibited tumor angiogenesis and tumor growth. Thus, use of AAV-mediated survivin mutant (Cys84Ala) is a promising strategy in colon cancer gene therapy.


Subject(s)
Colonic Neoplasms/genetics , Colonic Neoplasms/therapy , Dependovirus/genetics , Genetic Therapy/methods , Microtubule-Associated Proteins/genetics , Mutation, Missense , Alanine , Amino Acid Substitution , Apoptosis , Cell Division , Cell Line, Tumor , Colonic Neoplasms/pathology , Cysteine , Gene Transfer Techniques , Genetic Vectors , Humans , Inhibitor of Apoptosis Proteins , Mitosis , Neoplasm Proteins , Survivin
SELECTION OF CITATIONS
SEARCH DETAIL
...