Role ofHelicobacter pyloriinfection in pathogenesis of gastric carcinoma

Abstract

Gastric cancer (GC) is one of the most common carcino ma and the second leading cause of cancerrelated deaths worldwide. Helicobacter pylori (H. pylori ) infection causes a series of precancerous lesions like gastritis, atrophy, intestinal metaplasia and dysplasia, and is the strongest known risk factor for GC, as supported by epidemiological, preclinical and clinical studies. However, the mechanism of H. pylori developing gastric carcinoma has not been well defined. Among infected individuals, approximately 10% develop severe gastric lesions such as peptic ulcer disease, 1%3% progresses to GC.

Review: Prevalence and dynamics of Helicobacter pylori infection during childhood

“…Given the numbers summarized in our meta‐analysis, it is difficult to conceive that nearly 70% of the population has chronic inflammation of the stomach and that most were infected with H. pylori during childhood. Finally, most reviews indicate that nearly 10% of infected individuals will develop ulcer disease and 1%‐3% gastric cancer, which would, if the above estimates are true, lead to nearly 525 million individuals living with peptic ulcer (10% of 70% population) and 52‐157 million with gastric cancer (assuming 1%‐3% of the infected population [70%]). These numbers grossly surpass current estimates of nearly 1 million new gastric cancer cases worldwide per year .…”

“…152 Given the numbers summarized in our meta-analysis, it is difficult to conceive that nearly 70% of the population has chronic inflammation of the stomach and that most were infected with H. pylori during childhood. Finally, most reviews indicate that nearly 10% of infected individuals will develop ulcer disease and 1%-3% gastric cancer, 3 For the United States, with a population of 350 million, it was estimated that nearly 80 000 people lived with gastric cancer in 2013 (0.0002%).…”

“…2 Peptic ulcer disease is estimated to develop in ~10% of infected individuals 3 and has an annual incidence of 0.12%-1.5%, based on data from the USA and Europe. 4 Gastric cancer develops in 1%-3% of H. pylori infected individuals, 3,5 with an estimated 952 000 new cases of gastric cancer and 723 000 cancer associated deaths annually. 6 Helicobacter pylori infection seems to be acquired largely during childhood [7][8][9] and understanding the dynamics and outcomes associated with infection at early ages may prove critical for the design and relationship to atopy and its metabolic role in the microbiome.…”

Association between GSTM1, GSTT1, and GSTP1 polymorphisms and gastric cancer risk, and their interactions with environmental factors

“…Incidence of this disease varies across different populations, suggesting that environmental factors play an important role in its pathogenesis. Studies have shown that many environmental factors such as Helicobacter pylori infection, long-term smoking, longterm drinking, family history of cancer, high intake of pickled food, low intake of fruits and vegetables, and high salted diet contribute to the development of gastric cancer (Khayatzadeh et al, 2015;den Hoed and Kuipers, 2016;Lee et al, 2016;Zhang et al, 2016). However, not all individuals with associated risk factors develop gastric cancer, suggesting that genetic factors may also contribute to its pathogenesis.…”

Genetic polymorphisms in TNIP1 increase the risk of gastric carcinoma

“…GC is a complex and heterogeneous disease influenced by genetic and environmental factors [4]. Environmental factors including dietary habits, smoking and chronic atrophic gastritis caused mainly by Helicobacter pylori infections are known GC risk factors [5].…”