Gastric cancer, Helicobacter pylori infection and other risk factors

Gastric cancer incidence is declining. However, it is too early to consider this neoplastic disease as rare and the worldwide mortality rate still remains high. Several risk factors have been identified for non-cardia gastric cancer and primary prevention is feasible since most of the risk factors can be removed. Helicobacter pylori eradication treatment reduces but does not abolish gastric cancer risk. Indeed, gastric cancer is a multifactorial disease and removing one factor does not therefore prevent all cases. Endoscopic surveillance is still needed, especially in subjects at higher risk. The definition of high-risk patients will be the future challenge as well as identifying the best surveillance strategy for such patients.     

幽门螺杆菌感染与结直肠癌相关性的研究

目的:探讨幽门螺杆菌(Helicobacter pylori,Hp)感染与结直肠癌的相关性.方法:分析2015年6月至2020年6月郑州大学第一附属医院诊治的70例结直肠癌患者,选取同期于本院体检的99例健康体检者为对照组,应用13C尿素呼气试验检测结直肠癌组与对照组的Hp感染率.结果:对照组Hp阳性51例,阳性率51...     

幽门螺杆菌感染与胰腺癌发病相关性的Meta分析

目的:探讨幽门螺杆菌(Helicobacter pylori,Hp)感染与胰腺癌发病的相关性。方法:收集1990年-2013年国内外公开发表的关于幽门螺杆菌感染与胰腺癌发病相关性的病例对照研究的文献,应用Review Manager4.2软件Meta分析,计算合并优势比（odd ratio,OR值）及OR值95％可信区间(confidence interval,CI),倒漏斗图法定性评价发表性偏倚。结果:共7篇相关文献入选,总样本量2641例,其中胰腺癌947例,对照组1694例,Meta分析得出幽门螺杆菌感染与胰腺癌发病合并OR值为1.40（95%CI为 1.04-1.89,Z=2.21,P=0.03）。本研究倒漏斗分析图形不对称,但经敏感性分析和计算失安全系数证明,发表性偏倚对结果有一定的影响。结论:幽门螺杆菌感染是胰腺癌发病的危险因素。     

幽门螺杆菌感染与胃癌及癌前病变中P21蛋白的表达

 用LSAB免疫组化法，对20例谓癌、22例异型增生、30例肠化生及13例正常组织进行了P21蛋白表达的检测。结果发现，胃癌、异型增生和肠化生的P21阳性者分别为13例（65.0%）,12例（60.0%）,11例（36.6%）,正常组织全部阴性；三种组织中，HP阳性病人的P21阳性率为41.6%（30/72）,明显高于HP阴性病人的8.3%（6/72）,有显着差别（P<0.01）.说明HP感染与P21过度表达存在着明显的相关性。提示HP感染可能通过ras癌基因的突变而参予致癌作用。     

Role of Helicobacter pylori infection among offspring or siblings of gastric cancer patients

A positive family history is an increased risk factor for gastric cancer within family members, and one of the possible causes of this is the intrafamilial clustering of Helicobacter pylori infection. Our study examined the prevalence of H. pylori infection, serum antibodies to CagA and VacA and atrophic gastritis and/or intestinal metaplasia in the offspring or siblings of gastric cancer patients. A total of 726 subjects included 300 relatives of 300 separate gastric cancer patients and 426 controls. All subjects underwent upper gastrointestinal endoscopic examination with a rapid urease test. Blood samples were obtained to test for the presence of serum antibodies to the CagA and VacA proteins of H. pylori. The prevalence of H. pylori infection was higher in relatives of cancer patients (75.3%) than in controls (60.1%), and the adjusted odds ratio was 2.1 (95% CI 1.5-2.9). When either siblings or 2 or more family members were gastric cancer patients, the prevalence of H. pylori infection was much higher compared to the prevalence in controls. There was no specific relationship between CagA and VacA, and H. pylori infection. Atrophic gastritis and/or intestinal metaplasia were more frequently found in H. pylori-infected relatives of cancer patients (26.1%) than in H. pylori-infected controls (12.9%). These results strongly support a role for H. pylori infection in familial aggregation of gastric cancer. The prophylactic eradication of H. pylori infection in the offspring or siblings of gastric cancer patients may be clinically beneficial.     

Role of Helicobacter pylori infection and chronic inflammation in gastric cancer in the cardia

BACKGROUND: Helicobacter pylori-induced gastritis is an important factor for gastric carcinogenesis. However, it is still controversial whether it is also applicable for cardiac cancer development. Recently, we reported that H. pylori is an important factor for the induction of cardiac inflammation. We examined the status of H. pylori-induced gastritis in patients with cardiac cancer. METHODS: Seventy-five Japanese patients (58 men; mean age, 64.2 years) with cardiac cancer were studied. Cardiac cancer was defined as that mainly located within 2 cm from the squamo-columnar junction (SCJ). Histological gastritis including the cardiac region was evaluated using the biopsy or surgically resected sections. Cardiac inflammation was evaluated at 1 cm distal from SCJ in lesser curvature. Sera were collected and several markers were evaluated. The status of H. pylori infection was evaluated by histology and serum antibodies. Expressions of cytokeratins were examined by immunohistochemical analysis. RESULTS: Out of 75 patients with cardiac cancer, H. pylori was positive in 71 (95%) patients. The cardiac inflammation was examined in 30 patients (26 with H. pylori and four without H. pylori infection) and we found cardiac inflammation was present in all cases with H. pylori infection. Histologically, H. pylori-related gastritis was also found in the gastric corpus and antrum. Serological data were consistent with the presence of chronic atrophic gastritis. Intestinal metaplasia was found in 18 cases in the cardiac mucosa, and their cytokeratin 7/20 pattern was judged as a gastric pattern in all cases. CONCLUSION: H. pylori infection is closely associated with cardiac cancer.     

Severe atrophic gastritis with Helicobacter pylori infection and gastric cancer

Background. We conducted a case-control study to evaluate whether patients with severe gastric atrophy (indicated by serum pepsinogen concentration) have a high risk of gastric cancer. Methods. At the time of diagnosis of gastric cancer, sera from 301 patients (cases) and 602 sex- and age-matched cancer-free individuals (controls) were tested for the presence of anti-Helicobacter pylori IgG antibody (HM-CAP enzyme-linked immunoassay [ELISA] kit; Kyowa Medix, Tokyo, Japan) and serum pepsinogen (PG) levels (PG I and II Riabead Kits; Dainabot, Tokyo, Japan). We defined positivity for pepsinogen a pepsinogen I concentration of less than 70 ng/mL and a PG I/II ratio of less than 3.0. We categorized the subjects according to serum pepsinogen levels and anti-Helicobacter pylori IgG antibody, creating four categories. Results. Of the 301 cancer cases, 177 had positive serum pepsinogen levels, and 172 were positive for anti-Helicobacter pylori IgG antibody. The category in which subjects had positive serum pepsinogen levels and were negative for anti-Helicobacter pylori IgG antibody had the highest proportion (76.9%) of individuals with gastric cancer and the highest odds ratio (4.20) of the four categories. The odds ratios were 2.55 (95% confidence interval; 1.92–3.88) for positive serum pepsinogen levels and 0.93 (95% confidence interval; 0.63–1.27) for positive anti-Helicobacter pylori IgG antibody. Conclusion. These results suggest that patients with positive serum pepsinogen levels who are negative for IgG antibody to Helicobacter pylori, constitute a high-risk group for gastric cancer. Helicobacter pylori infection is associated with the development of gastric cancer by providing a suitable environment i.e., severe gastric atrophy, for carcinogenesis of the gastric mucosa. Received for publication on Mar. 20, 1998; accepted on Aug. 20, 1998     

幽门螺杆菌与大肠癌相关性研究进展

幽门螺杆菌(Hp)感染与大肠癌之间关系的研究发现,大肠癌及其相关腺瘤患者的Hp感染率较高,提示Hp有可能通过自身毒力和升高血浆胃泌素水平等方式作用于局部和远处的大肠黏膜细胞致癌,Hp感染是大肠癌的一种潜在危险因素.     

Serum biomarkers for the differentiation of autoimmune pancreatitis from pancreatic ductal adenocarcinoma

Autoimmune pancreatitis(AIP), a chronic inflammation caused by the immune system attacking the pancreas, usually presents imaging and clinical features that overlap with those of pancreatic ductal adenocarcinoma(PDAC). Serum biomarkers, substances that quantitatively change in sera during disease development, are a promising non-invasive tool with high utility for differentiating between these diseases. In this way, the presence of AIP is currently suspected when serum concentrations of immunogl...     

Epidemiology of Helicobacter pylori and gastric cancer

Findings in epidemiological studies of the relationship between Helicobacter pylori and gastric cancer have been inconsistent: many studies have yielded a positive relationship, whereas several studies have shown no relationship. The inconsistency arises because of the occurrence of seroreversion during the period between the time that H. pylori exerts a carcinogenic effect and the time of blood sampling. When this seroreversion is taken into account, there is an epidemiologically positive association between H. pylori status and the risk for gastric cancer. In addition to the epidemiological evidence, experimental studies using Mongolian gerbils have shown that H. pylori infection elevates the risk for gastric cancer. It is concluded that H. pylori is a causal factor for gastric cancer. In the creation of preventive strategies against gastric cancer by the eradication of H. pylori, determination of the time at which H. pylori plays a role as a carcinogen is important. Three hypotheses have been proposed in regard to this timing: that H. pylori infection in childhood or the teenage years acts as a factor that produces precancerous lesions with irreversible damage in the gastric mucosa, that in adulthood it acts as an initiator, and also in adulthood, that it acts as a promoter. As these hypotheses are not mutually exclusive, the extent to which each hypothesis plays a part in explaining gastric carcinogenesis should be evaluated. Only a small proportion of subjects infected with H. pylori have gastric cancer during their lifetime. Interleukin-1 polymorphism, a host factor, and CagA, a virulence factor of H. pylori, are suspected to be risk factors for gastric cancer in subjects with H. pylori infection. Dietary factors, especially vitamin C, and patterns of precancerous lesions also seem to influence the relationship between H. pylori and gastric cancer. H. pylori seems to reduce the risk for esophageal and for some gastric cardia adenocarcinomas. This finding, as well as determination of the time at which H. pylori exerts this preventive effect, should be considered in the creation of preventive strategies against gastric cancer that target the eradication of H. pylori. Received: June 1, 2001 / Accepted: October 16, 2001     

CagA+ Helicobacter pylori infection and gastric cancer risk in the EPIC-EURGAST study

Helicobacter pylori (H. pylori), atrophic gastritis, dietary and life-style factors have been associated with gastric cancer (GC). These factors have been evaluated in a large case-control study nested in the European Prospective Investigation into Cancer and Nutrition carried out in 9 countries, including the Mediterranean area. Participants, enrolled in 1992-1998, provided life-style and dietary information and a blood sample (360,000; mean follow-up: 6.1 years). For 233 GC cases diagnosed after enrolment and their 910 controls individually-matched by center, gender, age and blood donation date H. pylori antibodies (antilysate and antiCagA) and plasma Pepsinogen A (PGA) were measured by ELISA methods. Severe chronic atrophic gastritis (SCAG) was defined as PGA circulating levels <22 microg/l. Overall, in a conditional logistic regression analysis adjusted for education, smoke, weight and consumption of total vegetables, fruit, red and preserved meat, H. pylori seropositivity was associated with GC risk. Subjects showing only antibodies anti-H. pylori lysate, however, were not at increased risk, while those with antiCagA antibodies had a 3.4-fold increased risk. Overall, the odds ratio associated with SCAG was 3.3 (95% CI 2.2-5.2). According to site, the risk of noncardia GC associated with CagA seropositivity showed a further increase (OR 6.5; 95% CI 3.3-12.6); on the other hand, a ten-fold increased risk of cardia GC was associated with SCAG (OR 11.0; 95% CI 3.0-40.9). These results support the causal relationship between H. pylori CagA+ strains infection, and GC in these European populations even after taking into account dietary habits. This association was limited to distal GC, while serologically defined SCAG was strongly associated with cardia GC, thus suggesting a divergent risk pattern for these 2 sites.     

Helicobacter pylori and Pancreatic Cancer Risk: a Metaanalysis Based on 2,049 Cases and 2,861 Controls

Aim: Helicobacter pylori (H. pylori) have been considered as a risk factor for many cancers. We conducted thismeta-analysis to clarify the association between H. pylori infection and the risk of pancreatic cancer. Methods: Wesearched the Medicine/Pubmed and Embase databases, studies about the association between H. pylori infectionand pancreatic cancer published up to Jan.2014 were included. Finally, a total of 9 studies were used for this ameta-analysis. The odds ratios (ORs) and 95% confidence interval (95%CI) of H. pylori infection on pancreaticcancer with respect to control groups were evaluated. Two authors independently assessed the methodologicalquality and extracted data. This meta-analysis was conducted using software, state (version 12.0) to investigateheterogeneity among individual studies and to summarize the studies. Using the fixed-effects or random-effectsmodel, depending on the absence or presence of significant heterogeneity. Sensitivity analysis was performed toassess the influence of each individual study on the pooled ORs by omitting a single study each time. Publicationbias was evaluated by funnel plot, using Egger’s and Begg’s tests. Results: There was no significant associationbetween H. pylori infection and pancreatic cancer risk in the summary ORs,(OR=1.06, 95%CI: 0.74-1.37)through the random-effect method, but heterogeneity among studies was significant (I2=58.9%), so we putthe studies into two subgraphs (eastern and western). The results about western (OR=1.14 95%CI:0.89, 1.40)showed heterogeneity among the western countries of I2=6.6%, with no significant association between Hp+and pancreatic cancer, but the eastern countries (OR=0.62, 95%CI:0.49, 0.76), I2=0, suggested that decreasingpancreas-cancer risk in subjects with Hp+ infection. Simultaneously, 7 studies examined CagA+ strains was(OR=0.84 95%CI:0.63, 1.04), I2=36% with the random-effect method, subgraphs indicated that CagA+ coulddecrease the risk of pancreatic cancer in the eastern subjects (OR=0.66, 95%CI:0.52-0.80), but the associationwas not statistically significant in the western subjects (OR=0.95, 95%CI:0.73, 1.16). Conclusion: Hp+ andCagA+ infection are associated with a decreased risk of pancreatic cancer in eastern populations but have nosignificant associations in western countries.     

Prevalence of Helicobacter pylori infection in gastric remnant after distal gastrectomy for primary gastric cancer

Background. The development of a second primary cancer in the gastric remnant after gastrectomy for early gastric carcinoma is a problem, and eradication of Helicobacter pylori after the operation has been recommended. However, to date, practical indications for H. pylori eradication after gastric cancer surgery have not yet been reported. Methods. We examined H. pylori infection in the gastric remnant after distal gastrectomy for primary gastric cancer. One hundred and nine patients who had had a gastrectomy were studied. Endoscopic findings and results from the urease test, bacteriologic assessment, serological test, and histopathological examination were analyzed. Results. Seventy-one patients (65.1%) were judged to be positive for H. pylori infection. The prevalence of H. pylori infection was found to be significantly decreased in older patients, patients in whom the operation had been performed a long time before examination, patients with symptoms, and patients with severe reflux gastritis. On the other hand, histologically, chronic and acute gastritis correlated significantly with H. pylori infection. H. pylori prevalence was highest in mildly atrophic mucosa and decreased with more extensive atrophic changes of the mucosa. Conclusions. The persistence of H. pylori -related active gastritis in the gastric remnant after gastric cancer surgery was suggested in younger patients with mild atrophic gastritis and without reflux gastritis. These patients may be the best candidates for H. pylori eradication therapy. Received: April 13, 2001 / Accepted: June 18, 2001     

Interaction of cyclooxygenase-2 promoter polymorphisms with Helicobacter pylori infection and risk of gastric cancer

Overexpression of cyclooxygenase (COX)-2 has been implicated in the development of cancer. This study aimed to evaluate the relationship between genetic variants in COX-2 promoter interacting with Helicobacter pylori and the susceptibility to gastric cancer (GC). Three COX-2 polymorphisms -1290A>G (rs689465), -1195G>A (rs689466), and -765G>C (rs20417) were genotyped in 323 GC patients and 944 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression model. In GC patients, the ORs were 2.33 (95% CI = 1.50-3.63) and 2.70 (95% CI = 1.68-4.33) for -1195AA and -765CG genotype carriers, respectively. Haplotype analysis showed all -1195A allele-containing haplotypes, except G(-1290)-A(-1195)-G(-765), were associated with increased risk for GC, compared with the A(-1290)-G(-1195)-G(-765) haplotype. Moreover, significant multiplicative and additive interactions were observed between H. pylori infection and all these three polymorphisms, and H. pylori-infected subjects carrying the variant allele of -1290A>G, -1195G>A, or -765G>C had increased risk of GC compared with non-H. pylori-infected subjects with wild-type allele (OR = 4.10, 95% CI = 1.90-8.83; OR = 3.46, 95% CI = 1.31-9.11; and OR = 3.32, 95% = 1.27-8.73, respectively). Our results suggested that the COX-2 promoter polymorphisms were associated with increased risk of GC, especially interacting with H. pylori infection.     

Helicobacter pylori infection and gastric cancer: facing the enigmas

At an individual level Helicobacter pylori was associated with the occurrence of gastric cancer but in some African and Asian countries its prevalence runs with low gastric cancer rates, the so-called African and Asian enigmas. We assessed whether the association between gastric cancer and H. pylori prevalence at an area level is modified by the level of exposure to fruits and vegetables, alcohol or tobacco. Regression models were fitted to data from 58 countries using as dependent variable log transformed gastric cancer rates and as independent covariables the H. pylori prevalence, fruits and vegetables consumption, cigarette smoking, alcohol intake and interaction terms. The levels of alcohol consumption or cigarette smoking modified the association between gastric cancer and H. pylori infection. Models including H. pylori prevalence, alcohol consumption, cigarette smoking and the interaction terms H. pylori x alcohol or H. pylori x tobacco were used to compute gastric cancer incidence multiplying regression coefficients by a H. pylori prevalence of 85% (the approximate median in African countries) and the median figures observed in each continent for alcohol and tobacco availability. The expected gastric cancer incidence per 100,000 would be 5.7 assuming the alcohol and tobacco availability in African countries, 7.0 in Asia and Oceania, 16.0 in America and 26.0 in Europe. The interaction between H. pylori and cigarette or alcohol consumption may contribute to further explain the international variation in gastric cancer and the so-called African and Asian enigmas.     

From Helicobacter pylori infection to gastric cancer: Current evidence on the immune response

Gastric cancer (GC) is the result of a multifactorial process whose main components are infection by Helicobacter pylori (H. pylori), bacterial virulence factors, host immune response and environmental factors. The development of the neoplastic microenvironment also depends on genetic and epigenetic changes in oncogenes and tumor suppressor genes, which results in deregulation of cell signaling pathways and apoptosis process. This review summarizes the main aspects of the pathogenesis of GC and the immune response involved in chronic inflammation generated by H. pylori.     

幽门螺杆菌与残胃癌

残胃癌发病与幽门螺杆菌感染密切相关,幽门螺杆菌能促进残胃黏膜上皮细胞增殖,促进胃液中亚硝基化合物的产生及人体某些基因异常表达,最终促使残胃癌发生.根除幽门螺杆菌感染有望减少残胃癌的发生.     

Global burden of gastric cancer attributable to Helicobacter pylori

We previously estimated that 660,000 cases of cancer in the year 2008 were attributable to the bacterium Helicobacter pylori (H. pylori), corresponding to 5.2% of the 12.7 million total cancer cases that occurred worldwide. In recent years, evidence has accumulated that immunoblot (western blot) is more sensitive for detection of anti‐H. pylori antibodies than ELISA, the detection method used in our previous analysis. The purpose of this short report is to update the attributable fraction (AF) estimate for H. pylori after briefly reviewing new evidence, and to reassess the global burden of cancer attributable to H. pylori. We therefore reviewed the literature for studies comparing the risk of developing non‐cardia gastric cancer (NCGC) in cases and controls, using both ELISA and multiple antigen immunoblot for detection of H. pylori. The results from prospective studies were combined, and the new pooled estimates were applied to the calculation of the AF for H. pylori in NCGC, then to the burden of infection‐related cancers worldwide. Using the immunoblot‐based data, the worldwide AF for H. pylori in NCGC increased from 74.7% to 89.0%. This implies approximately 120,000 additional cases of NCGC attributable to H. pylori infection for a total of around 780,000 cases (6.2% instead of 5.2% of all cancers). These updated estimates reinforce the role of H. pylori as a major cause of cancer.     

Helicobacter pylori infection and gastric carcinogenesis in animal models

The effects of Helicobacter pylori infection on gastric disorders have been proven by many epidemiological and experimental studies. To explore the relationships between H. pylori infection and gastric carcinogenesis, many factors, including host responses, environmental status, and the virulence factors of the bacteria should be taken into account. Mongolian gerbils ( Meriones unguiculatus ) can be easily infected with H. pylori , and provide an excellent in-vivo experimental model to clarify the role of H. pylori in active gastritis, peptic ulcers, intestinal metaplasia, and gastric carcinoma. Studies have revealed that H. pylori infection markedly enhances all histological types of gastric cancers in gerbils treated with a chemical carcinogen. Eradication reduced the enhancing effect of H. pylori on gastric carcinogenesis, whereas a high-salt diet synergistically enhanced the effect of H. pylori . Various factors involving inflammation, cell proliferation, and cell differentiation could be examined with this experimental model to help elucidate this mechanisms of gastric carcinogenesis. Received: October 23, 2002 / Accepted: December 9, 2002 Acknowledgments We thank Dr. Toshiko Kumagai, Central Clinical Laboratories, Shinshu University Hospital; Dr. Atsushi Sugiyama, First Department of Surgery, Shinshu University; Professor Tsutomu Katsuyama, Department of Laboratory Medicine, Shinshu University School of Medicine; and Dr. Nobuyuki Shimizu and Professor Michio Kaminishi, Department of Gastrointestinal Surgery, Postgraduate School of Medicine, The University of Tokyo. Offprint requests to: M. Tatematsu