High Risk Of Stomach Cancer Research Articles

Modern aspects of Helicobacter pylori infection

A systematic review of current data on the structure and functions of Helicobacter pylori (Hp), pathogenesis, diagnosis and treatment of Hp-infection is presented. The relevance of the topic of helicobacteriosis is due to the proven connection of this infection with chronic, widespread diseases of the digestive organs among the population. The review used materials from the databases including PubМed, Medline, EMBASE, Scopus, Google Scholar, RSCI. A systematic review based on studies with a high degree of evidence has shown significant progress in the diagnosis and treatment of Hp-infection in recent years in adults and children. Coordination of the scientific search for the regularities of the formation of Hp-associated forms of pathology, continuous improvement of diagnostic technologies and the search for new therapies, periodic well-organized international revisions of standard methods of Hp diagnosis and treatment contribute to the creation of effective methods of Hp eradication, preservation of the optimal composition of the microbiota of the gastrointestinal tract and prevention of antibiotic resistance. Of particular importance for the prevention of complications of Hp-infection are original diagnostic algorithms using specialized endoscopic and molecular technologies before and after Hp eradication with long-term follow-up and the determination of the leading factors correlating with a high risk of stomach cancer. The review indicates the emergence of potentially effective and promising areas for the diagnosis and treatment of Hp-infection, including genetic modification of the Hp genome to ensure its existence as a human symbiont and a significant reduction in its pathogenic properties. At the same time, sequencing of a new generation reveals mutations in Hp genes associated with its pathogenicity and antibiotic resistance, which contributes to the creation of new classes of drugs to increase the effectiveness of Hp eradication with a decrease in the proportion of antibiotics and an increase in pathogenetically significant inhibitors of its pathogenic factors for the prevention of side effects, a significant reduction in the empirical use of several antibiotics and increased compliance to treatment.

Adherence to Pro-Vegetarian Food Patterns and Risk of Oesophagus, Stomach, and Pancreas Cancers: A Multi Case-Control Study (The PANESOES Study).

We aimed to evaluate the association between three previously defined pro-vegetarian (PVG) food patterns and the cancers of the oesophagus, stomach, and pancreas in a multi case-control study. We analyzed data from a multi-case hospital-based study carried out in two Mediterranean provinces in Spain. A total of 1233 participants were included in the analyses: 778 incident cancer cases, histologically confirmed (199 oesophagus, 414 stomach, and 165 pancreas) and 455 controls. A dietary assessment was performed using a validated food frequency questionnaire (FFQ). Three PVG food patterns (general, healthful, and unhealthful) were estimated using 12 food groups for the general PVG (gPVG), scoring positive plant-based foods and negative animal-based foods, and 18 food groups, for the healthful (hPVG) and unhealthful (uPVG) food patterns. Multinomial logistic regression was used to estimate relative risk ratios (RRR) and confidence intervals (95% CI) for quintiles of adherence to PVG patterns and as a continuous variable. The RRR (95% CI) for the highest vs. the lowest quintile of gPVG were, RRR = 0.37 (0.32, 0.42) for the oesophagus, RRR = 0.34 (0.27, 0.43) for the stomach, and RRR = 0.43 (0.35, 0.52) for pancreas cancer. For the hPVG, the RRR were RRR = 0.72 (0.58, 0.90) for the oesophagus, RRR = 0.42 (0.34, 0.52) for the stomach, and RRR = 0.74 (0.59, 0.92) for pancreas cancer. The uPVG was associated with a higher risk of stomach cancer RRR = 1.76 (1.42, 2.18). Higher adherence to gPVG and hPVG food patterns is associated with a lower risk of oesophageal, stomach, and pancreas cancers, while a higher adherence to a uPVG food pattern is associated with a higher risk of stomach cancer.

Risk factors modification as a preventive strategy in mortality reduction caused by digestive organs malignant neoplasms

Purpose of this study is to research contribution of chronic non-communicable diseases (CNCDs) risk factors (RF) to the prevalence rate of digestive organs diseases and risks of digestive system malignant neoplasms development in the context of Omsk region municipal districts. Material and methods: the analysis includes following risk factors (RF): unhealthy diets, overweight, harmful use of alcohol, physical inactivity with proved causal relationship with of digestive organs diseases such as stomach and duodenal ulcer, gastritis and duodenitis, liver fibrosis and liver cirrhosis, and with digestive organs malignant neoplasms (MNP): esophageal cancer, stomach cancer, colon cancer, rectal cancer, liver cancer and intrahepatic bile ducts cancer. This research used Russian Federation Federal State Statistics Service statistic material. Statistic material processing was conducted using traditional correlation analysis and the estimation of reliability of data differences method. Correlation analysis was carried out using online-calculator of statistics on the www.medstatistic.ru website. Results: the group of region municipal districts with the most unfavorable population mortality rates for malignant neoplasms has “unhealthy diets” RF associated with high risk of stomach cancer development, “overweight” RF associated with high risk of colorectal cancer and liver cancer development, “harmful use of alcohol” RF associated with high risk of stomach cancer and pancreatic cancer development, “physical inactivity” RF associated with high risk of stomach cancer development. Conclusion: the analysis made it possible to determine priorities in primary prevention of oncological diseases strategy in Omsk region municipal districts and to form key MNP development risk groups among region population to be targeted by preventive measures.

Trends in high-risk rates and screening rates for the population-based cancer screening program on esophageal, stomach and liver cancer in China, 2010-2016

BackgroundA population-based cancer screening program in rural China, targeting three types of cancer that are most prevalent in these areas, including esophageal, stomach, and liver cancer was awarded by the government in China since 2007. A two-step design with cancer risk assessment based on questionnaire interview and HBsAg test strip and subsequent clinical intervention for high-risk populations was adopted with free of charge at the local hospitals designated in the program. The participate rate including high-risk rates and screening rates was important to find appropriate strategies to improve the overall awareness of the program. MethodsData from the cancer screening program between 2010 and 2016 were used to calculate higher rate (high-risk population/ participants recruited) and screening rate (participants received screening/ high-risk population). ResultsFrom 2010 to 2016, 1,637,429 residents were recruited in the program and filled the questionnaires, 350,646 (21.4%) for esophagus cancer, 273,715 (16.7%) for stomach cancer and 1,013,068 (61.9%) for liver cancer. 471,974 participants were assessed as high-risk population including 114,786 (24.3%) high risk for esophagus cancer, 161,809 (34.3%) high risk for stomach cancer and 195,379 (41.4%) high risk for liver cancer, respectively. 249,185 (52.8%) participants who were assessed as high risk received clinical screening. There were 64,710 (26.0%) for esophagus cancer screening, 71,365 (28.6%) for stomach cancer screening and 113,110 (45.4%) for liver cancer screening, respectively. ConclusionOur findings will provide important references for designing effective population-based screening strategies to enhance the screening acceptance by health action plan in the future.

Qualitative analysis of water quality deterioration and infection by Helicobacter pylori in a community with high risk of stomach cancer (Cauca, Colombia).

This study looks at aspects of the environmental health of the rural population in Timbío (Cauca, Columbia) in relation to the deterioration of water quality. The information was obtained through participatory research methods exploring the management and use of water, the sources of pollution and the perception of water quality and its relation to Helicobacter pylori infection. The results are part of the qualitative analysis of a first research phase characterizing water and sanitation problems and their relation to emerging infectious diseases as well as possible solutions, which was carried out between November 2013 and August 2014. The results of this research are discussed from an ecosystemic approach to human health, recognizing the complexity of environmental conflicts related to water resources and their impacts on the health of populations. Through the methodology used, it is possible to detect and visualize the most urgent problems as well as frequent causes of contamination of water resources so as to propose solutions within a joint agenda of multiple social actors.

P53 Codon 72 Polymorphism Interactions with Dietary and Tobacco Related Habits and Risk of Stomach Cancer in Mizoram, India

This study was carried out to investigate the interaction of p53 codon 72 polymorphism, dietary and tobacco habits with reference to risk of stomach cancer in Mizoram, India. A total of 105 histologically confirmed stomach cancer cases and 210 age, sex and ethnicity matched healthy population controls were included in this study. The p53 codon 72 polymorphism was detected by PCR-RFLP and sequencing. H. pylori infection status was determined by ELISA. Information on various dietary and tobacco related habits was recorded with a standard questionnaire. This study revealed that overall, the Pro/ Pro genotype was significantly associated with a higher risk of stomach cancer (OR, 2.54; 95%CI, 1.01-6.40) as compared to the Arg/Arg genotype. In gender stratified analysis, the Pro/Pro genotype showed higher risk (OR, 7.50; 95%CI, 1.20-47.0) than the Arg/Arg genotype among females. Similarly, the Pro/Pro genotype demonstrated higher risk of stomach cancer (OR, 6.30; 95%CI, 1.41-28.2) among older people (>60 years). However, no such associations were observed in males and in individuals <60 years of age. Smoke dried fish and preserved meat (smoke dried/sun dried) consumers were at increased risk of stomach cancer (OR, 4.85; 95%CI, 1.91-12.3 and OR, 4.22; 95%CI, 1.46-12.2 respectively) as compared to non-consumers. Significant gene-environment interactions exist in terms of p53 codon 72 polymorphism and stomach cancer in Mizoram. Tobacco smokers with Pro/Pro and Arg/Pro genotypes were at higher risk of stomach cancer (OR, 16.2; 95%CI, 1.72-153.4 and OR, 9.45; 95%CI, 1.09-81.7 respectively) than the non-smokers Arg/Arg genotype carriers. The combination of tuibur user and Arg/Pro genotype also demonstrated an elevated risk association (OR, 4.76; 95%CI, 1.40-16.21). In conclusion, this study revealed that p53 codon 72 polymorphism and dietary and tobacco habit interactions influence stomach cancer development in Mizoram, India.

Abstract 4807: Soy and salty food intake and risk of stomach cancer in Seoul Male Cohort.

Abstract Stomach cancer is the most common cancer among men in Korea. High prevalence of H. pylori infection and salty food intake has been suspected to be the main contributors of the high incidence of stomach cancer in Korea. Many studies reported an inverse association between soy food and risk of stomach cancer, but some studies showed that fermented soy food increased the risk of stomach cancer probably due to the high concentration of salt in it. We aimed to evaluate the association between fermented and non-fermented soy, and other salty food and the risk of stomach cancer in a prospective cohort study in Korea. Seoul Male Cohort was established in 1993. Members were recruited from the male beneficiaries of the Korean Health Insurance Company, who were aged 40-59 and living in Seoul. A lifestyle questionnaire survey was conducted through mailing. Dietary intake was measured using a quantitative food frequency questionnaire with 88 food items. Cancer occurrence was identified through data linkage to the Korean Central Cancer Registry and Korean Death Records. A total of 14,512 members were followed up until December 31, 2008, and 362 stomach cancer cases were identified. Total calorie adjusted multivariable odds ratio (aOR) and 95% confidence interval (95%CI) were calculated using logistic regression. Soybean paste stew, a very popular fermented soy food in Korea, was positively associated with the risk of stomach cancer. Men who ate soybean paste stew 2∼3 cups per week had 1.45 times higher risk of stomach cancer than men who ate less than one cup per week (95% CI = 1.11-1.92). Non-fermented soy foods, including soybean, tofu, and soy drink, were not associated with the risk of stomach cancer. The aOR of stomach cancer for the highest intake of soybean compared to the lowest intake was 1.02 (95%CI = 0.77-1.36), for the highest intake of tofu was 1.05 (95%CI = 0.75-1.46), for the highest intake of soy drink was 1.11 (95%CI = 0.84-1.47). Other salty foods, including Kimchi stew (highest vs. lowest, aOR=1.47, 95%CI=1.05-2.06), and salt-fermented radish (highest vs. lowest, aOR=1.45, 95%CI=1.11-1.90) were positively associated with the risk of Stomach cancer. However, Kimchi itself, the most popular salt-fermented vegetable in Korea, was not associated with the risk of stomach cancer (highest vs. lowest, aOR=1.06, 95%CI=0.77-1.46). In conclusion, we found no evidence of inverse association between non-fermented soy food and risk of stomach cancer. When soy is fermented, its high concentration of salt may increase the risk of stomach cancer. Most of the other salty foods may increase the risk of stomach cancer. Citation Format: Myung-Hee Shin, Seon-Mi Hwang, Jong-Myon Bae, Moo-Song Lee, Dong-Hyun Kim, Zhong-Min Li, Yoon-Ok Ahn. Soy and salty food intake and risk of stomach cancer in Seoul Male Cohort. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4807. doi:10.1158/1538-7445.AM2013-4807

Polymorphisms of the formylpeptide receptor gene (FPR1) and susceptibility to stomach cancer in 1531 consecutive autopsy cases

Formylpeptide receptor (FPR1) is involved in inflammation, which is important in the pathogenesis of diverse conditions, including common diseases and cancers. To date, little is known about the relationships between FPR1 and such diseases, aside from the fact that FPR1 is related to periodontitis, which is implicated in systemic diseases such as stomach cancer. We hypothesized that FPR1 polymorphisms related to periodontal disease may confer susceptibility to stomach cancer. Two single nucleotide polymorphisms (SNPs) in the second extracellular region and C-terminus of the formylpeptide receptor gene were analyzed in 1531 consecutive autopsy cases in the Japanese elderly. The tri-allelic SNP of rs1042229 was detected by modified melting temperature analysis. Homozygous K alleles of rs1042229 were associated with stomach cancer (Odds ratio [OR] = 1.62, confidence interval [CI] = 1.05–2.48, p = 0.028). In the analysis of the recessive model of the K allele, FPR1 was associated with a high risk of stomach cancer (OR = 1.73, CI = 1.15–2.55, p = 0.0075). The risk allele for stomach cancer pointed in the same direction as periodontitis. This is the first study to evaluate polymorphisms of the FPR1 gene in stomach cancer to find a positive association between these polymorphisms and stomach cancer. Further studies on the relationship between stomach cancer and the FPR1 gene are warranted.

Environmental Tobacco Smoke and Stomach Cancer Risk

P-199 Introduction: Smoking is a risk factor of stomach cancer, although the data on environmental tobacco smoke (ETS) and risk of the disease are not sufficient. Therefore, we tried to assess an association of stomach cancer risk and ETS. The methods: A case-control study included 77 cases aged 25–85 with newly histologically confirmed diagnose of stomach cancer and 181 randomly selected controls that were cancer and stomach diseases free. Cases and controls were matched by gender, age (±5 yr) and residence. A questionnaire made on the basis of Aichi Cancer Center's Questionnaire was used to collect information on ETS at home and workplace as well as on other possible risk factors of stomach cancer. Unconditional logistic regression was used to calculate odds ratios (OR) and corresponding 95% confidence intervals (CI). The results: More than one third (36.5%) of cases and 16.3% of controls were exposed to ETS for half of a workday and longer at workplace (p<0.05), 36.5% of cases and 34.3% of controls experienced exposure to ETS at home (p>0.05). After controlling for age, gender, alcohol use, smoking, family history on cancer and some dietary items (noodles, margarine, butter, beef, pate, salted meat, cabbage, tomato, garlic, onion, yellow and green vegetables, paprika, fruits, pickled vegetables and mushrooms) that were associated with stomach cancer, significant elevation in stomach cancer risk was observed for the subjects exposed to ETS at workplace (OR=5.2, 95% CI=1.95–13.87 sometimes vs. not exposed; OR=7.59, 95% CI=2.58–22.4 half of a workday and longer vs. not exposed). Increased risk of the disease was found for the subjects exposed to ETS at home or at workplace (OR=3.9, 95% CI=1.45–10.47 vs. not exposed), and for those exposed to ETS at both home and workplace settings (OR=3.2, 95% CI=1.04–9.9 vs. not exposed). Duration of exposure to ETS was also associated with higher risk of stomach cancer (OR=9.55, 95% CI=3.39–26.88 less than 20 yrs vs. not exposed; OR=4.01, 95% CI=1.47–10.95 more than 20 yrs vs. not exposed). Conclusion: The findings suggest that environmental tobacco smoke is related to increased risk of stomach cancer.

Cigarette Smoking and Mortality due to Stomach Cancer: Findings from the JACC Study.

BACKGROUND: Several epidemiologic studies reported the positive association between cigarette smoking and stomach cancer. The prevalence of smoking in men remains high in Japan compared to other developed countries. It is therefore of great importance to determine the impact of cigarette smoking on stomach cancer among the Japanese population. The Japan Collaborative Cohort Study (JACC Study) provided an opportunity to examine the association between smoking and the risk of mortality due to stomach cancer.METHOD: A baseline survey was conducted throughout Japan from 1988 through 1990 among 110,792 inhabitants of 45 areas. Data retrieved for 98,062 participants (43,482 male and 54,580 female) who provided sufficient information about their smoking habits, without any history of caner at the baseline. Of total 970,251 person-years, 757deaths due to stomach caner were identified.RESULTS: Current smokers were at a higher risk of death due to stomach cancer than non-smokers (Hazard ratio = 1.36; 95% confidence interval [CI]: 1.07, 1.73). The risk of stomach cancer for men who smoked 15 or more cigarettes per day was approximately 1.4-fold greater than that of non-smokers, and those who smoked 35 or more cigarettes per day had an approximately 1.7-fold higher risk of stomach cancer, although the dose-response trend among men was unclear (p for trend = 0.063). No associations between smoking and stomach cancer were detected among women.CONCLUSION: The present results, together with previous findings, strongly support a hypothesis that cigarette smoking increases the risk of stomach cancer in Japanese men.

Methylenetetrahydrofolate reductase genotypes, dietary habits and susceptibility to stomach cancer

OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dielary habits and the risk of stomach cancer (SC). METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian. Jiangsu province, China. The epiderniological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects. MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or Ttq genotypes was found to be significantly different between conlrols (685%) and SC cases (79.4%. P---0 0416), the increased risk had an adjusted OR of 1.79 (95%Cl: 1.01 - 3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intake of meat: the carriers of the MTHFR C/'T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The potyrnorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their expos[ire tevel to environmental factors.

Eradication rate of Helicobacter pylori in a Mexican population at high risk for gastric cancer and use of serology to assess cure

OBJECTIVES: Helicobacter pylori causes gastric adenocarcinoma. We assessed the success of H. pylori eradication therapy in a medically underserved population in Chiapas, Mexico, that is at high risk for gastric cancer risk. METHODS: Healthy volunteers with both antibodies to CagA and gastrin levels ≥25 ng/ml were randomly assigned to receive either a combination of omeprazole, amoxicillin, and clarithromycin or matched placebo for 1 wk. Endoscopy with seven biopsies was performed at baseline, at 6 wk, and 1 yr after treatment. Treatment success was defined as loss of H. pylori by histological analysis. Cure was assessed using change in serology based on the standardized absorbance of a H. pylori ELISA. RESULTS: H. pylori eradication rates were high (intent-to-treat analysis: 76.3% [95% CI = 68.7–84.0%] after 6 wk and 76.1% [95% CI = 67.7–84.6%] after 1 yr; per protocol analysis: 77.8% [95% CI = 70.1–85.4%] after 6 wk and 75.2% [95% CI = 66.5–84.0%] after 1 yr). Nine subjects on active treatment and one subject on placebo who were without H. pylori at 6 wk were infected at 1 yr (recurrence rates 10.7% and 33.3%, respectively, p = 0.31). Median changes in standardized absorbance at 1 yr were 47% and 1% for successfully and unsuccessfully treated patients, respectively. A 10% decline in standardized absorbance after 1 yr had 84% sensitivity and 100% specificity for H. pylori eradication. CONCLUSIONS: Even with a short course of treatment against H. pylori, a high rate of eradication rate can be achieved in populations at high risk for stomach cancer. Serum antibodies are useful in assessing efficacy of therapy.

Helicobacter pylori infection and mode of transmission in a population at high risk of stomach cancer.

Helicobacter pylori (H. pylori) is a recognized cause of chronic gastritis and peptic ulcer disease, and is strongly suspected to play a role in the aetiology of stomach cancer but little is known about the mode of transmission. To determine the prevalence of H. pylori infection in children and investigate potential modes of transmission in rural China. We examined 98 children aged 3-12 years and 289 adults aged 35-64 years in a village in Linqu County, China, which has one of the highest rates of stomach cancer in the world. H. pylori infection was determined by 13C-urea breath test in children and by an enzyme-linked immunosorbent assay in adults. Among 98 tested children, 68 (69%) were H. pylori positive, but the prevalence rates varied as a function of age, rising from about 50% at ages 3-4 to 85% at ages 9-10 before falling to 67% at ages 11-12. Boys had a higher infection rate than girls (77.8% versus 59.1%, P < 0.05). Among 289 adults, 195 (68%) were H. pylori positive, with a somewhat higher rate of positivity in younger compared to older age groups. The prevalence of H. pylori infection clustered within families. In families with at least one infected parent, 85% of children were H. pylori positive, while in families with both parents uninfected, only 22% of children were H. pylori positive (odds ratio [OR] = 30.4, 95% CI : 4.0-232). These findings demonstrate the acquisition of H. pylori infection during early childhood in a population at high risk of stomach cancer, in a manner consistent with a person-to-person mode of transmission between parents and children.

Serum antioxidant vitamins and risk of lung and stomach cancers in Shenyang, China

In a hospital-based case control study, we measured serum concentrations of vitamin A, β-carotene and vitamin E for subjects with cancer (58 cases of lung cancer and 22 cases of stomach cancer) and 63 matched controls in Shenyang, China. Lung cancer patients had significantly ( P<0.01) lower mean serum levels of vitamin A, β-carotene and vitamin E than controls, while the mean serum level of vitamin E did not differ between stomach cancer patients and the controls. Lower serum levels of vitamin A, vitamin E and β-carotene were associated with an increased risk of lung cancer. Lower serum levels of vitamin A and β-carotene were associated with a higher risk of stomach cancer, although the number of cases was small. An increased risk of lung cancer associated with lower serum levels of vitamin A and vitamin E was more evident among heavy smokers than among non-heavy smokers.

Determinants of plasma anti-oxidant vitamin levels in a population at high risk for stomach cancer

Our objective was to identify the determinants of plasma levels of anti-oxidant vitamins which have been linked with decreased risk of cancer and other chronic diseases. Correlation analyses were performed between baseline plasma levels of ascorbic acid, alpha- and beta-carotenes, cryptoxanthin, lycopene and alpha- and gamma-tocopherols and baseline information on dietary and other demographic and life-style factors among 1,364 subjects 35-69 years of age, who are participants in a chemoprevention trial on pre-cancerous lesions of the stomach in Venezuela. Males had lower levels of ascorbic acid, alpha- and beta-carotene and cryptoxanthin and higher levels of alpha-tocopherol than females. This finding was confirmed in non-smokers and non-drinkers. In females, but not in males, age was positively associated with levels of ascorbic acid, cryptoxanthin, alpha- and beta-carotene and gamma-tocopherol. Male tobacco users had lower plasma levels of ascorbic acid, alpha- and beta-carotene and cryptoxanthin than nonusers, and regular alcohol drinkers had a decreased plasma levels of beta-carotene compared with non-drinkers. Female tobacco users had lower levels of ascorbic acid and cryptoxanthin than non-users, and regular alcohol drinkers had lower levels of ascorbic acid and lycopene than non-drinkers. Frequencies of consumption of fresh fruits, fruit juice, raw vegetables and plantains showed weak positive associations with plasma levels of several vitamins studied in both sexes. Sex, age in females, tobacco and alcohol use and dietary consumption affected plasma anti-oxidant vitamin levels in this population significantly. These factors may influence the effect of anti-oxidant treatment in intervention trials.

Determinants of plasma pepsinogen levels in a population at high risk for stomach cancer in venezuela

Determinants of plasma pepsinogens (PG) levels were studied in 1365 participants in a chemoprevention trial for gastric pre-cancerous lesions being conducted in Venezuela. Gastric biopsies, plasma samples and information on smoking and dietary habits were obtained at baseline examination. Both PG-I and PG-II levels increased progressively with the level of Helicobacter pylori infection in gastric biopsies, resulting in no clear trend in the I/II ratio. Instead, there was a progressive decrease in the I/II ratio with increasing degrees of infiltration of polynuclear cells and monocytes, atrophy, intestinal metaplasia and the stage of pre-cancerous lesions. The mean I/II ratios for atrophic gastritis or more advanced lesions were less than 4.0. When subjects with the I/II ratio 4 or higher were used as controls, severe reduction in the I/II ratio (< 2.0) was inversely associated with tobacco consumption. This may be due to a pharmacological effect of nicotine. The severe reduction of I/II ratio was also inversely associated with fresh fruit consumption. In addition, a decreased I/II ratio was positively associated with rice/pasta and arepas (tortilla made from corn) consumption and inversely associated with plantain consumption. Possible effects of vitamins and starchy food on the development of atrophic gastritis need to be studied further.

Factors influencing serum pepsinogen levels in a Chinese population at high risk of stomach cancer

The relationships between serum pepsinogen (PG) levels and age, sex, ABO blood type, cigarette smoking and diet were studied among over 3, 000 residents selected at random in an area with high risk of stomach cancer in Shandong Province, China. Males had significantly higher median PG I and II levels than feamles. PG I tended to decrease and PG II to rise with age. Subjects with blood type A had a higher PG II level than subjects with other blood types. Both PG I and II levels rose with daily consumption of cigarettes. Alcohol consumption was not related to PG levels. The PG I/ II ratio declined with increasing consumption of sour pancakes, a fermented staple food found to contain N-nitroso compounds and to be a risk factor for stomach cancer in this population.

Biomarkers of individual susceptibility to carcinogens: Application for biological monitoring

In order to develop new markers of individual susceptibility to various human carcinogens, we studied some parameters of formation and metabolism of carcinogens, as well as DNA adducts formation and DNA repair in animals and humans. Following an i.p. administration of benzo(a)pyrene (BP) to the rats, levels of urinary excretion of BP-7,8-diol correlated with tumour latency. A high correlation was found between excretion of this metabolite and BP-DNA adducts level in the liver. Healthy smokers excreted higher quantities of BP-7,8-diol, than smoking lung cancer patients, thus confirming the suggestion on existence of cancer-prone phenotype. N-nitroso compounds formed most efficiently in stomach juice of children with superficial gastritis who therefore could be at high risk of stomach cancer. N-ethyl-N'-nitro-N-nitrosoguanidine induced stomach cancer earlier in monkeys with a low level of DNA repair enzyme, O6-alkylguanine-DNA alkyltransferase (AGT) in gastric mucosa. Overall, these markers can be helpful in predicting individual susceptibility to carcinogens.

Detection of GST1 gene deletion by the polymerase chain reaction and its possible correlation with stomach cancer in Japanese.

A homozygous gene deletion at the GST1 locus of genomic DNA isolated from peripheral blood was investigated for its relationship with several types of cancer using the polymerase chain reaction (PCR) technique. DNA samples were prepared from blood obtained from 128 healthy blood donors and 150 patients with cancer or chronic hepatitis. PCR primers were prepared based on the human cDNA sequence and the intron/exon sequences of the rat Yb2 gene. The amplified sequence between exons 5 and 6 including intron 5 showed very clearly the presence of absence of the GST1 gene, after electrophoresis in a 2% agarose gel. Segregation of the presence and absence of PCR product from samples of twins and their parents indicated that presence involves homozygous or heterozygous normal GST1 genotypes while absence involves only homozygous gene deletion. The patients with stomach cancer had a significantly higher frequency of gene deletion than did the healthy controls (P < 0.005). Thus, GST1 deletion may be a possible genetic marker for early detection of a group at high risk of stomach cancer.

DNA methylation damage in individuals at high risk for stomach cancer

DNA methylation damage in individuals at high risk for stomach cancer