Initial presentation and management of osteosarcoma, and its impact on disease outcome

OBJECTIVE

To evaluate the initial presenting symptoms and management of osteosarcoma in Hong Kong Chinese children, in relation to any possible impact on disease outcomes.

DESIGN

Retrospective study.

SETTING

A tertiary referral centre of bone cancer in a university teaching hospital in Hong Kong.

PATIENTS

All children aged younger than 18 years with a diagnosis of osteosarcoma who received treatment from March 1994 to October 2005.

RESULTS

A total of 51 children were studied. The median age of onset was 13 (range, 3-20) years; 61% were males. The tumours were located in the distal femur and proximal tibia, which accounted for 45% and 22% of the cases, respectively; 24% of patients had metastatic disease at presentation. Swelling (76%) and pain (90%) were the most common presenting complaints. Approximately one third of the patients had a preceding history of trauma. The median duration of initial symptoms to first medical consultation of any sort was 30 (range, 0-360) days. The median time from the first consultation to a definitive diagnosis was 21 (range, 0-350) days; 25% were diagnosed more than 52 days after presentation. Bonesetters were initially consulted by 37% of these patients. From presentation to diagnosis, the median duration was 61 (range, 4-361) days. Analysis of the duration of pre-diagnosis symptoms did not correlate significantly with the development of metastatic disease, response to chemotherapy, feasibility of limb salvage surgery, relapse rates, or survival rates.

CONCLUSIONS

In Hong Kong, initial consultation to bonesetters was common. A relatively long delay in between symptom onset and diagnosis of osteosarcoma was encountered. The public and medical practitioners should be made aware of this disease, especially in adolescents.

Single nucleotide polymorphisms of complement component 5 and periodontitis

BACKGROUND AND OBJECTIVE

Polymorphisms of host defence genes might increase one's risks for periodontitis. This study investigated whether tagging single nucleotide polymorphisms (SNPs) of the gene encoding complement component 5 (C5) are associated with periodontitis in a Hong Kong Chinese population.

MATERIAL AND METHODS

Eleven tagging SNPs of 229 patients with at least moderate periodontitis and 207 control subjects without periodontitis were genotyped using an i-plexGOLD MassARRAY mass-spectrometry system.

RESULTS

Genotype AG of SNP rs17611 was more prevalent in the group of periodontitis patients than in the controls (54.6% vs. 41.7%, p = 0.007). The haplotype CGCA of the haplotype block consisting of rs1035029, rs17611, rs25681 and rs992670 was significantly associated with periodontitis in a dominant model (p = 0.001). The SNP rs17611 showed high linkage disequilibrium with rs1035029, rs25681 and rs992670. Smoking was also significantly associated with periodontitis (p = 0.006).

CONCLUSION

The tagging SNP rs17611 of the C5 gene and smoking may be associated with periodontitis among the Hong Kong Chinese population.

Identification of retinoic acid-regulated nuclear matrix-associated protein as a novel regulator of gastric cancer

BACKGROUND

Retinoic acid-regulated nuclear matrix-associated protein (RAMP) is a WD40 repeat-containing protein that is involved in various biological functions, but little is known about its role in human cancer. This study aims to delineate the oncogenic role of RAMP in gastric carcinogenesis.

METHODS

RAMP expression was examined by real-time quantitative RT-PCR, immunohistochemistry and western blotting. Inhibition of RAMP expression was performed by siRNA-mediated knockdown. The functional effects of RAMP on cell kinetics were measured by cell viability assay, colony formation assay and flow cytometry. Cell lines stably expressing RAMP were established to investigate the oncogenic effects of RAMP in vitro.

RESULTS

Ramp was readily expressed in all seven gastric cancer cell lines and was significantly increased in human gastric cancer tissues when compared with their adjacent non-cancerous tissues (P<0.001). In keeping with this, expression of RAMP protein was higher in gastric cancer tissues compared with their adjacent non-cancerous tissues, whereas moderate protein expression were noted in intestinal metaplasia. Knockdown of RAMP in gastric cancer cells significantly reduced cell proliferation (P<0.01) and soft agar colony formation (P<0.001), but induced apoptosis and G(2)/M arrest. In additional, knockdown RAMP induced cell apoptosis is dependent on functional accumulation of p53 and p21 and induction of cleaved caspases-9, caspases-3 and PARP. Strikingly, overexpression of RAMP promoted anchorage-independent cell growth in soft agar.

CONCLUSION

Our findings demonstrate that RAMP plays an oncogenic role in gastric carcinogenesis. Inhibition of RAMP may be a promising approach for gastric cancer therapy.

Exploring the oral bacterial flora: current status and future directions

OBJECTIVE

The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods.

DESIGN

Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed.

METHODS

The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised.

RESULTS

Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species.

CONCLUSION

Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.

Predicting mortality in patients with bleeding peptic ulcers after therapeutic endoscopy

BACKGROUND & AIMS

Despite advances in management of patients with bleeding peptic ulcers, mortality is still 10%. This study aimed to identify predictive factors and to develop a prediction model for mortality among patients with bleeding peptic ulcers.

METHODS

Consecutive patients with endoscopic stigmata of active bleeding, visible vessels, or adherent clots were recruited, and risk factors for mortality were identified in this deprivation cohort by using multiple stepwise logistic regression. A prediction model was then built on the basis of these factors and validated in the evaluation cohort.

RESULTS

From 1993 to 2003, 3220 patients with bleeding peptic ulcers were treated. Two hundred eighty-four of the patients developed rebleeding (8.8%); emergency surgery was performed on 47 of these patients, whereas others were managed with endoscopic retreatment. Two hundred twenty-nine of these sustained in-hospital death (7.1%). In patients older than 70 years, presence of comorbidity, more than 1 listed comorbidity, hematemesis on presentation, systolic blood pressure below 100 mm Hg, in-hospital bleeding, rebleeding, and need for surgery were significant predictors for mortality. Helicobacter pylori-related ulcers had lower risk of mortality. The receiver operating characteristic curve comparing the prediction of mortality with actual mortality showed an area under the curve of 0.842. From 2004 to 2006, data were collected prospectively from a second cohort of patients with bleeding peptic ulcers, and mortality was predicted by using the model developed. The receiver operating characteristic curve showed an area under the curve of 0.729.

CONCLUSIONS

Among patients with bleeding peptic ulcers after endoscopic hemostasis, advanced age, presence of listed comorbidity, multiple comorbidities, hypovolemic shock, in-hospital bleeding, rebleeding, and need for surgery successfully predicted in-hospital mortality.

Bactericidal and sporicidal performance of a polymer-encapsulated chlorine dioxide-coated surface

Aims:  To investigate the physical characteristics and the bactericidal and sporicidal potential of a polymer‐encapsulated ClO₂ coating.

Methods and Results:  An antimicrobial coating based on polymer‐encapsulated ClO₂ was developed. A low viscosity, water/oil/water double emulsion coating was formulated for easy on‐site application. Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus were applied onto the coating to study the bactericidal capabilities of the coating. The bactericidal performance of the coating increased when the contact time with the tested bacteria increased. Over 99% of the E. coli, Ps. aeruginosa, B. subtilis were killed with a contact time of 30 min. Although endospores of B. subtilis are more resistant, about 75% of the spores were killed after 72 h on the coating. Moreover, a sustained release of gaseous ClO₂ was achieved to maintain about 90% removal of B. subtilis with a 10‐min contact time during a 28‐day study period. The coating also exhibits antiadhesive properties against bacteria.

Conclusions:  A polymer‐encapsulated ClO₂ coating with sustained release of ClO₂ and promising bactericidal and sporicidal features was tested for 28 days.

Significance and Impact of the Study:  This study provides a new direction for developing polymer‐encapsulated ClO₂ coatings that possess persistent bactericidal and sporicidal properties.

One man, one disease?

We report the case of a 12-year-old girl with a strong family history of malignancy who presented with immature teratoma and gliomatosis peritonei. Despite first and second line chemotherapy, the disease ran an unusually refractory course. Although the presentation was not the typical tumour presentation of Li-Fraumeni syndrome (LFS), we proceeded to undertake tumour genetic testing of the patient and her parents. LFS was diagnosed in this patient and her father with a sequence variation of CGG>TGG, R248W, which is one of the most common transcriptionally inactive mutations detected in LFS. Genetic counselling was offered to the father. A tumour screening programme and genetic screening for the p53 gene mutation for the surviving family members can be offered once consent is obtained from the father. This case illustrates the importance of cancer genetic study, even if the tumour presentation is not typical for any familial cancer syndrome.

Functional role of the KLF6 tumour suppressor gene in gastric cancer

Gastric cancer is the second most common cancer and a leading cause of cancer-related death worldwide. The Kruppel-like factor 6 (KLF6) tumour suppressor gene had been previously shown to be inactivated in a number of human cancers through loss of heterozygosity (LOH), somatic mutation, decreased expression and increased alternative splicing into a dominant negative oncogenic splice variant, KLF6-SV1. In the present study, 37 gastric cancer samples were analysed for the presence of loss of heterozygosity (LOH) of the KLF6 locus and somatic mutation. In total, 18 of 34 (53%) of the gastric cancer samples analysed demonstrated KLF6 locus specific loss. Four missense mutations, such as T179I, R198G, R71Q and S180L, were detected. Interestingly, two of these mutations R71Q and S180L have been identified independently by several groups in various malignancies including prostate, colorectal and gastric cancers. In addition, decreased wild-type KLF6 (wtKLF6) expression was associated with loss of the KLF6 locus and was present in 48% of primary gastric tumour samples analysed. Functional studies confirmed that wtKLF6 suppressed proliferation of gastric cancer cells via transcriptional regulation of the cyclin-dependent kinase inhibitor p21 and the oncogene c-myc. Functional characterisation of the common tumour-derived mutants demonstrated that the mutant proteins fail to suppress proliferation and function as dominant negative regulators of wtKLF6 function. Furthermore, stable overexpression of the R71Q and S180L tumour-derived mutants in the gastric cancer cell line, Hs746T, resulted in an increased tumourigenicity in vivo. Combined, these findings suggest an important role for the KLF6 tumour suppressor gene in gastric cancer development and progression and identify several highly cancer-relevant signalling pathways regulated by the KLF6 tumour suppressor gene.

Sjögren's syndrome sufferers have increased oral yeast levels despite regular dental care

AIM

To investigate the prevalence and quantity of oral yeasts and their association with oral candidiasis in Sjögren's syndrome (SS) patients receiving regular dental care.

MATERIALS AND METHODS

Yeasts in oral rinse and full-mouth supra-gingival plaque samples from 25 primary SS, 27 secondary SS and 29 control subjects were selectively cultured. All yeasts except single-species isolates were genotyped using pulsed field gel electrophoresis (PFGE).

RESULTS

Ten (19%) SS sufferers had symptomless candidiasis. SS subjects had a higher prevalence (73%vs 7%) and quantity of yeasts than controls in both oral rinse and plaque samples (P < 0.05). The prevalence of yeasts in plaque was associated with candidiasis regardless of denture wearing (P < or = 0.04). Candida albicans was the predominant yeast isolated. PFGE showed 20 (66% of total) C. albicans isolate pairs, i.e. C. albicans species isolated from plaque and oral rinse samples of the same individual, were of closely related genetic clonal types (P < 0.01).

CONCLUSIONS

Despite effective oral hygiene, more SS subjects than controls had detectable levels of oral yeasts and their presence in supra-gingival plaque was associated with candidiasis. Candida albicans colonized supra-gingival biofilm even in well-maintained SS individuals, posing a challenge to the control of oral candidiasis.

Caecal metastasis from a primary small-cell lung carcinoma

Small bowel metastases from a primary lung carcinoma are rare. We report a case of a 59-year-old male with a primary small-cell lung carcinoma who developed anaemia and bowel symptoms. On colonoscopic examination he was found to have a tumour in the caecum near the ileocaecal valve, which was biopsied, revealing small neuroendocrine tumour cells. The patient then underwent systemic chemotherapy, which achieved a reduction in the size of the primary lung tumour and an improvement in his bowel symptoms. It is important that such a rare condition be recognised early as complicated intestinal metastases from a lung carcinoma can lead to high mortality rates and poor short-term outcome. With advances in chemotherapy and palliative care, patients with metastatic lung carcinoma can sometimes survive more than a year with reasonable quality of life.

Comparison of EUS and ERCP in the investigation with suspected biliary obstruction caused by choledocholithiasis: a randomized study

BACKGROUND

EUS may be used to reduce the need of diagnostic ERCP.

OBJECTIVE

Our purpose was to investigate the benefits and safety of an EUS-guided versus an ERCP-guided approach in the management of suspected biliary obstructive diseases caused by choledocholithiasis, in whom a US study is not diagnostic.

DESIGN

A randomized study.

SETTING

A university medical unit.

PATIENTS

Patients with clinical, biochemical, or radiologic suspicion of biliary obstruction.

INTERVENTIONS

In the EUS group, therapeutic ERCP was performed at the same EUS session if a lesion was found. In the ERCP group, therapeutic treatment was carried out at the discretion of the endoscopist.

MAIN OUTCOME MEASUREMENTS

The number of ERCPs avoided, procedure-related complications, and recurrent biliary symptoms on follow-up at 1 year.

RESULTS

Thirty-three patients were randomized to EUS and 32 to ERCP. Three patients (9.4%) had failed ERCPs, whereas all EUS procedures were successful. Nine (27.3%) patients in the EUS group were found to have biliary lesions that were all treated by ERCP. In the ERCP group, 7 (22%) patients had biliary lesions detected that were treated in the same session. More patients had serious complications (bleeding, acute pancreatitis, and umbilical abscess) in the ERCP group. One patient in each group had recurrent biliary symptoms during follow-up. With EUS used as a triage tool, diagnostic ERCP and its related complications could be spared in 49 (75.4%) patients.

CONCLUSIONS

In patients suspected to have biliary obstructive disease, EUS is a safe and accurate test to select patients for therapeutic ERCP.

Phospholipase, proteinase and haemolytic activities of Candida albicans isolated from oral cavities of patients with type 2 diabetes mellitus

The aim of this study was to biotype and characterize phospholipase, proteinase and haemolytic activities of oral Candida albicans isolates from 210 Chinese patients with type 2 diabetes mellitus (DM) and 210 age- and sex-matched healthy controls. Seventy-six and 50 C. albicans isolates were obtained from type 2 DM patients and controls, respectively, using the oral rinse technique. The isolates were characterized with a biotyping system based on enzyme profiles, carbohydrate assimilation patterns and boric acid resistance of the yeasts, and the isolates were further tested for in vitro phospholipase, proteinase and haemolytic activities. The major biotypes of C. albicans isolates from the type 2 DM and control groups were A1R (42.1 %) and J1R (36.0 %), respectively. Significantly higher proteinase and haemolytic activities were found in the isolates from the type 2 DM group (P<0.05). Proteinase activity was higher in isolates from patients with > or =10 years of DM history than those with <10 years (P<0.05). Haemolytic activity was significantly higher in isolates from female DM patients than in those from male counterparts (P<0.05). These data provide evidence of increased extracellular enzyme activity in Candida isolates taken from DM patients.

The efficacy of cevimeline hydrochloride in the treatment of xerostomia in Sjögren's syndrome in southern Chinese patients: a randomised double-blind, placebo-controlled crossover study

Cevimeline hydrochloride, a specific agonist of the M3 muscarinic receptor, is beneficial in the treatment of symptoms of xerostomia and xerophthalmia associated with Sjögren's syndrome (SS). Cevimeline has not been evaluated in southern Chinese patients. Furthermore, the effects of cevimeline on health-related quality of life and oral health status are not known. In this randomised, double-blind, placebo-controlled crossover study, patients received cevimeline 30 mg or matched placebo three times per day over 10 weeks followed by a 4-week washout period before treatment crossover. Participants self-completed the following questionnaires: Xerostomia Inventory (XI), the General Oral Health Assessment Index (GOHAI), the Ocular Surface Disease Index (OSDI) and the Medical Outcomes Short Form (SF-36). Clinical assessments included sialometry, examination of the oral cavity for the degree of xerostomia and dental complications of xerostomia. Fifty patients (22 primary SS and 28 secondary SS) were enrolled in the trial. Forty-four patients completed the study. There was a significant improvement in the XI and GOHAI scores as well as the objective rating of xerostomic signs of the oral cavity after treatment with cevimeline. However, there was no improvement in salivary flow rates and dry eye symptoms. SS patients had lower SF-36 scores, but these did not improve after treatment with cevimeline.

Frequent epigenetic inactivation of secreted frizzled-related protein 2 (SFRP2) by promoter methylation in human gastric cancer

The role of secreted frizzled-related protein (SFRP) genes in gastric cancer remains largely unknown. We determined the frequency and functional significance of SFRPs hypermethylation in human gastric cancer. The expression and methylation status of four SFRP members (SFRP1, 2, 4, and 5) in primary gastric cancer samples was screened. The biological effects of SFRP were analysed by flow cytometry, cell viability assay and in vivo tumour growth in nude mice. Among the four SFRPs, only SFRP2 was significantly downregulated in gastric cancer as compared to adjacent non-cancer samples (P<0.01). Promoter hypermethylation of SFRP2 was detected in 73.3% primary gastric cancer tissues, 37.5% of samples showing intestinal metaplasia and 20% adjacent normal gastric tissues. Bisulphite DNA sequencing confirmed the densely methylated SFRP2 promoter region. Demethylation treatment restored the expression of SFRP2 in gastric cancer cell lines. Forced expression of SFRP2 induced cell apoptosis, inhibited proliferation of gastric cancer cells and suppressed tumour growth in vivo. Moreover, methylated SFRP2 was detected in 66.7% of serum samples from cancer patients but not in normal controls. In conclusion, epigenetic inactivation of SFRP2 is a common and early event contributing to gastric carcinogenesis and may be a potential biomarker for gastric cancer.

Supra-gingival microbiota in Sjögren’s syndrome

The aim of this study was to investigate the microbiota of noncaries associated supra-gingival plaque (SGP) microbiology in Sjögren's syndrome (SS). Stimulated whole saliva (SWS) and full-mouth SGP on intact tooth surfaces were collected from 26 primary (p) SS, 27 secondary (s) SS, and 29 control subjects for selective culture of lactobacilli, mutans streptococci, and aerobic and facultatively anaerobic gram-negative rods (AGNR). Predominant cultivable anaerobes from SGP of 11 randomly selected subjects from each group were investigated. Clinical and sialometric data were also collected. SS sufferers had significantly lower SWS flow rate and higher mean DMFT (decayed, missing, filled teeth), while pSS subjects also had lower SWS pH and fewer standing teeth. Lactobacillus acidophilus levels in SWS (P = 0.012) and SGP (P < 0.0001) were significantly elevated in pSS sufferers compared with sSS individuals and controls. AGNR isolation was uncommon. SS sufferers had significantly lower proportion of gram-negative species (P = 0.047). Non-oral species were isolated in greater proportions from pSS SGP (P = 0.007). Subjects with pSS harbored increased levels of L. acidophilus and non-oral species, while SS sufferers generally had lower proportions of gram-negative species. The microbial composition of noncaries associated SGP indicates a potential source of increased caries risk in SS.

Combination of a cyclo-oxygenase-2 inhibitor and a proton-pump inhibitor for prevention of recurrent ulcer bleeding in patients at very high risk: a double-blind, randomised trial

BACKGROUND

Guidelines on pain management recommend that patients at risk of ulcers receive either a cyclo-oxygenase (COX 2) inhibitor or a non-steroidal anti-inflammatory drug (NSAID) with a proton-pump inhibitor (PPI). These two treatments have similar effectiveness, but they are insufficient for protection of patients at very high risk for ulcer bleeding. We aimed to test the hypothesis that in patients with previous ulcer bleeding induced by non-selective NSAIDs, combined treatment with the COX 2 inhibitor celecoxib and the PPI esomeprazole would be better than celecoxib alone for prevention of recurrent ulcer bleeding.

METHODS

441 consecutively presenting patients who were taking non-selective NSAIDs for arthritis were recruited to our single-centre, prospective, randomised, double-blind trial after admission to hospital with upper-gastrointestinal bleeding. Patients were enrolled after their ulcers had healed and a histological test for Helicobacter pylori was negative. All patients were given 200 mg celecoxib twice daily. 137 patients were randomly assigned to receive 20 mg esomeprazole twice daily (combined-treatment group), and 136 to receive a placebo (control group) for 12 months. The primary endpoint was recurrent ulcer bleeding during treatment or within 1 month of the end of treatment. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00365313.

FINDINGS

Combination treatment was more effective than celecoxib alone for prevention of ulcer bleeding in patients at high risk. The 13-month cumulative incidence of the primary endpoint was 0% in the combined-treatment group and 12 (8.9%) in the controls (95% CI difference, 4.1 to 13.7; p=0.0004). The median follow-up was 13 months (range 0.4-13.0). Discontinuation of treatment and the incidence of adverse events were similar in the two treatment groups.

INTERPRETATION

Patients at very high risk for recurrent ulcer bleeding who need anti-inflammatory analgesics should receive combination treatment with a COX 2 inhibitor and a PPI. Our findings should encourage guideline committees to review their recommendations for patients at very high risk of recurrent ulcer bleeding.

Tooth loss in treated periodontitis patients responsible for their supportive care arrangements

AIM

To identify risk indicators associated with tooth loss and periodontitis in treated patients responsible for arranging supportive periodontal care (SPC).

MATERIALS AND METHODS

Ninety-seven Chinese subjects (34-77 years) who showed favourable responses to periodontal therapy provided in a teaching hospital 5-12 years previously were recalled. They were advised to seek regular SPC on discharge. Background information, general health status, smoking, oral hygiene habits, follow-up dental care, tooth loss, and periodontal parameters were investigated. Multiple regression analysis was performed.

RESULTS

Two hundred and fifty-six teeth had been lost, 195 because of self-reported periodontal reasons. Up to 26.8% sites were with pockets > or =6 mm. Positive correlations were found between total/periodontal tooth loss and (i) smoking pack-years, (ii) time spent on oral hygiene, (iii) years since therapy's conclusion, (iv) age, and negative correlations with (v) inter-dental brush use, and (vi) education levels. Tooth loss by arch was correlated with wearing of removable partial denture in that arch. Percentage sites with pockets > or =6 mm were significantly negatively correlated with percentage sites without bleeding on probing.

CONCLUSIONS

Smokers, more elderly patients, removable partial denture wearers, and patients with lower education levels or not using inter-dental brushes ought to be targeted for clinic-based SPC.

Effect of celecoxib on experimental liver fibrosis in rat

BACKGROUND/AIM

Cyclooxygenase-2 (COX-2), an inducible enzyme that catalyzes prostaglandin synthesis, has been implicated in a number of hepatic stellate cell (HSC) functions. In the current study, we assessed the in vivo effect of celecoxib, a COX-2-selective inhibitor, in experimental liver fibrosis in rats.

METHODS

Male Sprague-Dawley rats received experimental treatments for 5 weeks. Serum alanine transminase at the time of sacrifice was measured. Quantitative assessment of liver fibrosis was performed by computerized morphometry. Expression of COX-2, alpha smooth muscle actin and connective tissue growth factor (CTGF) was evaluated by immunohistochemistry. Real-time quantitative PCR was used to determine the expression of genes associated with fibrogenesis and extracellular matrix degradation.

RESULTS

Liver fibrosis was significantly worse in rats that received both carbon tetrachloride (CCl4) and celecoxib, compared with rats that received CCl4 and gavage of water (P = 0.037). There was also more HSC activation, and upregulation of collagen alpha1(I), heat-shock protein 47, alphaB crystallin, matrix metalloproteinase (MMP)-2, MMP-9 and tissue inhibitor of MMP (TIMP)-2. The expression of TIMP-1 and CTGF was not significantly different between the two groups. The pro-fibrogenic effect of celecoxib in toxin-induced liver fibrosis in rats was further confirmed in thioacetamide model of liver injury.

CONCLUSIONS

Celecoxib potentiates experimental liver fibrosis; further studies are warranted to investigate the potential pro-fibrogenic effect of celecoxib in other animal models of liver fibrosis and in patients with chronic hepatitis.

Peroxisome proliferator-activated receptor-gamma Pro12Ala polymorphism, Helicobacter pylori infection and non-cardia gastric carcinoma in Chinese

BACKGROUND

Peroxisome proliferator-activated receptor gamma inhibits the growth and induces apoptosis of gastric cancer cells. A common polymorphism at codon 12 of this gene (Pro12Ala) has been shown to confer protection against diabetes and colorectal cancer.

AIM

To study the association between peroxisome proliferator-activated receptor gamma gene polymorphism, Helicobacter pylori infection and gastric cancer in Chinese.

METHODS

One hundred and four consecutive patients with non-cardia gastric adenocarcinoma and 104 matched controls were examined. Peroxisome proliferator-activated receptor gamma Pro12Ala polymorphism was analysed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

The frequency of peroxisome proliferator-activated receptor gamma G (Ala12) allele was significantly higher among cancer patients (19.2%) than in control (8.7%; OR 2.5, 95% CI 1.1-5.8). While H. pylori infection was more prevalent in gastric cancer patients (OR 3.0; 95% CI 1.6-5.7), the combination of peroxisome proliferator-activated receptor gamma G allele and H. pylori infection further increased the risk of gastric cancer (OR 12.8, 95% CI 3.2-50.5). The presence of the Ala12 did not increase the risk of gastric cancer in H. pylori-negative subjects.

CONCLUSION

Our study suggests the potential association between peroxisome proliferator-activated receptor gamma polymorphism and H. pylori infection in the development of non-cardia gastric cancer.

Increasing incidence of colorectal cancer in Asia: implications for screening

Many Asian countries, including China, Japan, South Korea, and Singapore, have experienced an increase of two to four times in the incidence of colorectal cancer during the past few decades. The rising trend in incidence and mortality from colorectal cancer is more striking in affluent than in poorer societies and differs substantially among ethnic groups. Although changes in dietary habits and lifestyle are believed to be the reasons underlying the increase, the interaction between these factors and genetic characteristics of the Asian populations might also have a pivotal role. Non-polypoidal (flat or depressed) lesions and colorectal neoplasms arising without preceding adenoma (de novo cancers) seem to be more common in Asian than in other populations. The absence of polypoid growth preceding malignancy has posed difficulties in screening for early colorectal cancer by radiological imaging or even endoscopic techniques. Although epidemiological data are scanty, most Asian populations are not aware of the growing problem of colorectal cancer. More work is needed to elucidate the magnitude of the problem in Asia.

Increasing incidence of colorectal cancer in Asia: implications for screening

Many Asian countries, including China, Japan, South Korea, and Singapore, have experienced an increase of two to four times in the incidence of colorectal cancer during the past few decades. The rising trend in incidence and mortality from colorectal cancer is more striking in affluent than in poorer societies and differs substantially among ethnic groups. Although changes in dietary habits and lifestyle are believed to be the reasons underlying the increase, the interaction between these factors and genetic characteristics of the Asian populations might also have a pivotal role. Non-polypoidal (flat or depressed) lesions and colorectal neoplasms arising without preceding adenoma (de novo cancers) seem to be more common in Asian than in other populations. The absence of polypoid growth preceding malignancy has posed difficulties in screening for early colorectal cancer by radiological imaging or even endoscopic techniques. Although epidemiological data are scanty, most Asian populations are not aware of the growing problem of colorectal cancer. More work is needed to elucidate the magnitude of the problem in Asia.