Background Although many studies have found an association between Helicobacter pylori infection and the development of gastric cancer, many aspects of this relation remain uncertain. Methods We prospectively studied 1526 Japanese patients who had duodenal ulcers, gastric ulcers, gastric hyperplasia, or nonulcer dyspepsia at the time of enrollment; 1246 had H. pylori infection and 280 did not. The mean follow-up was 7.8 years (range, 1.0 to 10.6). Patients underwent endoscopy with biopsy at enrollment and then between one and three years after enrollment. H. pylori infection was assessed by histologic examination, serologic testing, and rapid urease tests and was defined by a positive result on any of these tests. Results Gastric cancers developed in 36 (2.9 percent) of the infected and none of the uninfected patients. There were 23 intestinal-type and 13 diffuse-type cancers. Among the patients with H. pylori infection, those with severe gastric atrophy, corpus-predominant gastritis, and intestinal metap...

Helicobacter pylori infection and the development of gastric cancer

Background. Infection with Helicobacter pylori has been linked with chronic atrophic gastritis, an inflammatory precursor of gastric adenocarcinoma. In a nested case–control study, we explored whether H. pylori infection increases the risk of gastric carcinoma. Methods. From a cohort of 128,992 persons followed since the mid-1960s at a health maintenance organization, 186 patients with gastric carcinoma were selected as case patients and were matched according to age, sex, and race with 186 control subjects without gastric carcinoma. Stored serum samples collected during the 1960s were tested for IgG antibodies to H. pylori by enzyme-linked immunosorbent assay. Data on cigarette use, blood group, ulcer disease, and gastric surgery were obtained from questionnaires administered at enrollment. Tissue sections and pathology reports were reviewed to confirm the histologic results. Results. The mean time between serum collection and the diagnosis of gastric carcinoma was 14.2 years. Of the 109 patient...

https://www.nejm.org/doi/pdf/10.1056/NEJM199110173251603

Helicobacter pylori infection and the risk of gastric carcinoma.

Beckman, Kenneth B., and Bruce N. Ames. The Free Radical Theory of Aging Matures. Physiol. Rev. 78: 547–581, 1998. — The free radical theory of aging, conceived in 1956, has turned 40 and is rapidl...

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The Free Radical Theory of Aging Matures

Approximately 200 studies that examined the relationship between fruit and vegetable intake and cancers of the lung, colon, breast, cervix, esophagus, oral cavity, stomach, bladder, pancreas, and ovary are reviewed. A statistically significant protective effect of fruit and vegetable consumption was found in 128 of 156 dietary studies in which results were expressed in terms of relative risk. For most cancer sites, persons with low fruit and vegetable intake (at least the lower one-fourth of the population) experience about twice the risk of cancer compared with those with high intake, even after control for potentially confounding factors. For lung cancer, significant protection was found in 24 of 25 studies after control for smoking in most instances. Fruits, in particular, were significantly protective in cancers of the esophagus, oral cavity, and larynx, for which 28 of 29 studies were significant. Strong evidence of a protective effect of fruit and vegetable consumption was seen in cancers of the pancreas and stomach (26 of 30 studies), as well as in colorectal and bladder cancers (23 of 38 studies). For cancers of the cervix, ovary, and endometrium, a significant protective effect was shown in 11 of 13 studies, and for breast cancer a protective effect was found to be strong and consistent in a meta analysis. It would appear that major public health benefits could be achieved by substantially increasing consumption of these foods.

Fruit, vegetables, and cancer prevention: A review of the epidemiological evidence

Evidence from pathology and epidemiology studies has been provided for a human model of gastric carcinogenesis with the following sequential stages: chronic gastritis; atrophy; intestinal metaplasia; and dysplasia. The initial stages of gastritis and atrophy have been linked to excessive salt intake and infection with Helicobacter pylori. The intermediate stages have been associated with the ingestion of ascorbic acid and nitrate, determinants of intragastric nitrosation. The final stages have been linked with the supply of beta-carotene and with excessive salt intake. Nitrosating agents are candidate carcinogens and could originate in the gastric cavity or in the inflammatory infiltrate.

https://cancerres.aacrjournals.org/content/canres/52/24/6735.full.pdf

Human Gastric Carcinogenesis: A Multistep and Multifactorial Process—First American Cancer Society Award Lecture on Cancer Epidemiology and Prevention

Background Helicobacter pylori infection is a risk factor for gastric adenocarcinoma. We examined whether this infection is also a risk factor for primary gastric non-Hodgkin's lymphoma. Methods This nested case-control study involved two large cohorts (230,593 participants). Serum had been collected from cohort members and stored, and all subjects were followed for cancer. Thirty-three patients with gastric non-Hodgkin's lymphoma were identified, and each was matched to four controls according to cohort, age, sex, and date of serum collection. For comparison, 31 patients with nongastric non-Hodgkin's lymphoma from one of the cohorts were evaluated, each of whom had been previously matched to 2 controls. Pathological reports and specimens were reviewed to confirm the histologic type of the tumor. Serum samples from all subjects were tested for H. pylori IgG by an enzyme-linked immunosorbent assay. Results Thirty-three cases of gastric non-Hodgkin's lymphoma occurred a median of 14 years after serum collec...

https://www.nejm.org/doi/pdf/10.1056/NEJM199405053301803

Helicobacter pylori Infection and Gastric Lymphoma

In a cross-sectional study, serum dehydroepiandrosterone sulfate (DS) concentrations were measured in 981 men and 481 women, aged 11-89, yr. The resulting data were asymetrically distributed and were normalized by logarithmic transformation and analyzed by 5-yr age grouping (e.g. 15-19 yr, 20-24 yr, etc.). The DS concentration peaked at age 20-24 yr in men (logarithmic mean, 3470 ng/ml) and at age 15-19 yr in women (log mean, 2470 ng/ml). Mean values then declined steadily in both sexes (log mean at greater than 70 yr of age, 670 ng/ml in men and 450 ng/ml in women) and were significantly higher in men than women at ages from 20-69 yr. Analysis of 517 randomly selected sera (from women) which had been stored frozen for 10-15 yr gave results indistinguishable from values obtained from fresh specimens. In a supplementary study, a longitudinal analysis of weekly specimens from 4 normal men, aged 36-59 yr, revealed individual variability (mean coefficient of variation, 19%) and failed to demonstrate any monthly, seasonal, or annual rhythmicity. Based on the above analyses, a table of normal serum DS ranges for adult men and women is presented for use as a clinical reference.

Age Changes and Sex Differences in Serum Dehydroepiandrosterone Sulfate Concentrations throughout Adulthood

BACKGROUND AND AIMS: It is not known why some people with Helicobacter pylori infection develop gastric cancer whereas others do not. Whether the CagA phenotype of H pylori infection affected risk for cancer independently of other posited risk factors was evaluated. SUBJECTS: 242 persons who participated in a previous nested case-control study of gastric cancer. 179 (90 cases and 89 controls) were infected with H pylori as determined by enzyme linked immunosorbent assay (ELISA) in serum and 63 (13 cases and 50 controls) were uninfected. METHODS: Serum samples from cases and controls, obtained a mean of 14.2 years before diagnosis of cancer in the cases, were tested by ELISA for IgG antibodies against the CagA gene product of H pylori. They had previously been tested for pepsinogen I. Using logistic regression analysis, risk for cancer was compared among infected persons with CagA antibodies, infected persons without CagA antibodies, and uninfected persons. RESULTS: Subjects infected with H pylori who had CagA antibodies were 5.8-fold more likely than uninfected subjects to develop gastric cancer (95% confidence interval (95% CI) = 2.6-13.0). This was true for both intestinal (odds ratio (OR) 5.1, 95% CI = 2.1-12.2) and diffuse type (OR 10.1, 95% CI = 2.2-47.4) cancers. By contrast, H pylori infected subjects without CagA antibodies were only slightly, and not significantly, at increased risk for cancer (OR 2.2, 95% CI = 0.9-5.4) and any possible association was restricted to diffuse type carcinoma (OR 9.0, 95% CI = 1.2-65.8). Pepsinogen 1 < 50 ng/ml significantly increased risk for both cancer types in H pylori infected persons and lessened the magnitude of association between CagA and cancer. Educational attainment, cigarette smoking, and ABO blood group were not associated with malignancy. CONCLUSIONS: When compared with uninfected subjects, persons infected with CagA positive H pylori are at considerably increased risk of gastric cancer. CagA negative H pylori are less strongly linked to malignancy and may only be associated with diffuse type disease.

https://gut.bmj.com/content/gutjnl/40/3/297.full.pdf

Risk for gastric cancer in people with CagA positive or CagA negative Helicobacter pylori infection.

Dietary energy restriction has been a widely used means of experimentally extending mammalian life span. We report here that lifelong reduction in the concentration of a single dietary component, the essential amino acid L-methionine, from 0.86 to 0.17% of the diet results in a 30% longer life span of male Fischer 344 rats. Methionine restriction completely abolished growth, although food intake was actually greater on a body weight basis. Studies of energy consumption in early life indicated that the energy intake of 0.17% methionine-fed animals was near normal for animals of their size, although consumption per animal was below that of the much larger 0.86% methionine-fed rats. Increasing the energy intake of rats fed 0.17% methionine failed to increase their rate of growth, whereas restricting 0.85% methionine-fed rats to the food intake of 0.17% methionine-fed animals did not materially reduce growth, indicating that food restriction was not a factor in life span extension in these experiments. The biochemically well-defined pathways of methionine metabolism and utilization offer the potential for uncovering the precise mechanism(s) underlying this specific dietary restriction-related extension of life span.

Norman Orentreich

Papers

Helicobacter pylori infection and the risk of gastric carcinoma.

Helicobacter pylori Infection and Gastric Lymphoma

Age Changes and Sex Differences in Serum Dehydroepiandrosterone Sulfate Concentrations throughout Adulthood

Risk for gastric cancer in people with CagA positive or CagA negative Helicobacter pylori infection.

Low Methionine Ingestion by Rats Extends Life Span