Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Helicobacter pylori (H. pylori), a long term colonizer of human stomach is known to infect a half of mankind. Gastric and duodenal ulcer, gastric adenocarcinoma and MALT lymphoma develop in a subset of infected individuals. Pathogenesis of H. pylori infection is based on the long-term host to bacterial interaction and affected by the virulence factors of the bacterium, environmental and host factors (age, sex, blood type). Mucosal inflammation is the basic principle mechanism underlying the disease development in which tissue destruction may be initiated and maintained by both the bacterial toxins (CagA, VacA, LPS) and immune responses by the host. Immune evasion with bacterial modulation of host response affects the long-term host colonization. Colonization is also affected by urease and/or motility of the bacterium, presence of lipopolysaccharide (LPS) and various bacterial enzymes. Gastric mucosal atrophy and intestinal metaplasia can develop during the course of H. pylori infection predisposing to carcinogenesis. Host cytokine gene polymorphism would be the one explanation for host susceptibility to peptic ulcer or gastric cancer. Investigation into the pathogenesis of H. pylori related diseases could provide an answer to the impact of chronic host to microbial interaction resulting human diseases.
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PMID:[Pathogenesis of Helicobacter pylori infection]. 1617 34

Host response plays a major role in the pathogenesis of Helicobacter pylori-induced gastroduodenal disease including adenocarcinoma of the distal stomach. Vascular endothelial growth factor (VEGF) is an important modulator of gastric mucosal repair and is overexpressed in gastric cancer. The present study sought to evaluate the expression of VEGF in the gastric mucosa of H. pylori-infected and H. pylori-non-infected dyspeptic patients. Fifteen H. pylori-infected and 15 H. pylori-non-infected dyspeptic patients were studied. Diagnosis of H. pylori infection was based on rapid urease test and histology. VEGF protein expression was assessed by western blotting. VEGF mRNA expression was assessed by RT-PCR. VEGF localization in the gastric mucosa and neo-angiogenesis were determined by immunohistochemistry. VEGF protein and mRNA expression was significantly greater in H. pylori-infected than in non-infected patients. Immunohistochemistry showed that VEGF expression was more intense in the gastric gland compartment of H. pylori-infected mucosa than in the non-infected mucosa. The increase in VEGF expression was associated with a significant increase in neo-angiogenesis as assessed by determination of CD34-positive micro-vessels. H. pylori gastritis is therefore associated with up-regulation of VEGF expression, which parallels the increased formation of blood vessels in the gastric mucosa. It is postulated that increased VEGF expression and neo-angiogenesis may contribute to H. pylori-related gastric carcinogenesis.
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PMID:Vascular endothelial growth factor and neo-angiogenesis in H. pylori gastritis in humans. 1618 19

Helicobacter pylori (Hp) infection is an important factor in human gastric disorders, including chronic active gastritis, peptic ulcers, intestinal metaplasia and cancer. Since epidemiologic studies overwhelmingly agree on a protective influence of fruits and vegetables in reducing the risk of gastric neoplasia and processed foods made from Prunus mume Sieb. et Zucc. (Japanese apricot or "Ume" in Japanese) are traditionally known for their miscellaneous medical effects, in the present study we investigated the efficacy of a fruit-juice concentrate of Japanese apricot (CJA) in the glandular stomach of Hp-infected Mongolian gerbils. Hp-inoculated gerbils were given CJA in their drinking water at concentrations of 1 and 3% for 10 weeks. The microscopic scores for gastritis and mucosal hyperplasia in the CJA groups were significantly lower than in the Hp-inoculated control group, with dose-dependence. Real-time PCR was performed to quantitate Hp by demonstrating urease A gene amount using gerbils glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene as an internal control. Average relative urease A gene dosage in the glandular stomach in the 1 and 3% CJA and Hp-inoculated control groups was 26.6 +/- 11.6% (average +/- SE), 30.3 +/- 10.5%, 100 +/- 40.9%, respectively, the fruit-juice concentrate causing significant lowering (P<0.01 and P<0.05, respectively, with 1 and 3%). These findings suggest that suppressive effects on gastric cancer development might also be expected as a result of decreased numbers of Hp and improvement of Hp-induced chronic active gastritis on administration of CJA.
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PMID:Suppressive effects of fruit-juice concentrate of Prunus mume Sieb. et Zucc. (Japanese apricot, Ume) on Helicobacter pylori-induced glandular stomach lesions in Mongolian gerbils. 1623 96

Helicobacter pylori is a spiral, gram-negative rod-shaped pathogen that attaches to gastric epithelial cells in the human stomach and is a causative agent of chronic active gastritis, peptic ulcer and neoplasia. H. pylori is one of the most common pathogens afflicting humans and is the major environmental factor in the development of gastric cancer increasing from 4 to 6 folds the risk of its development. Several specific virulence factors are implicated in the mechanism of H. pylori infection like the bacterial motility; the secretion of large amounts of urease; specific adhesins for the interaction between H. pylori and the gastric surface epithelium; the traslocation into gastric ephitelial cells of the cytotoxin-associated gene A (CagA), the vacuolating cytotoxin A (VacA) and the heat shock protein HspB. Adherence of H. pylori to the gastric epithelium and secretion of interleukins are believed to be an important step in the induction of active inflammation of the mucosal layer. Several studies have demonstrated that H. pylori infection induces gastric epithelial cell proliferation activating ERK and MAPK pathways and increase of mitosis and mutations. Therefore, H. pylori infection seems to increase apoptosis, implying increased gastric epithelial cell turnover. Recently, it has been shown that H. pylori-induced apoptosis in gastric epithelial cells is mediated via the CD95-receptor/ ligand system but that TRAIL also plays an important role in this regulation.
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PMID:Helicobacter pylori and gastric epithelial cells: from gastritis to cancer. 1627 May 19

A 65-kDa tumor-associated protein (P65) is a potential non- specific tumor marker expressed by many types of tumor cells. Our recent studies indicate that P65 gene expression is connected with poor prognosis for the patients with colorectal cancer. In the present study P65 gene expression was determined by means of RT-PCR in the group of 22 gastric cancer and adjacent normal gastric mucosa. Its presence was correlated with some parameters of clinical staging. P65 gene expression was also determined in 102 tissue antral gastric endoscopic biopsy specimens from the patients suspected of H. pylori infection. The presence of H. pylori infection was determined by urease test. We found that in the group of gastric cancers, similarly to colorectal cancer, P65 gene expression was connected with poor clinicopathological parameters as T3, lymph nodes and distant metastases. There was no dependence between P65 gene expression and H. pylori infection. However, more often P65 gene expression was detected in the group of infected men than women. There was also a statistically significant dependence between age and P65 gene expression in the group of people above 60 years old. It could be then postulated that P65 gene expression is connected with poor prognosis for the patients suffering from gastric cancer and that this expression does not depend on H. pylori infection.
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PMID:Expression of the P65 gene in gastric cancer and in tissues with or without Helicobacter pylori infection. 1628 90

Helicobacter pylori is a Gram-negative neutralophile associated with peptic ulcers and gastric cancer. It has a unique ability to colonize the human stomach by acid acclimation. It uses the pH-gated urea channel, UreI, to enhance urea access to intrabacterial urease and a membrane-anchored periplasmic carbonic anhydrase to regulate periplasmic pH to approximately 6.1 in acidic media, whereas other neutralophiles cannot regulate periplasmic pH and thus only transit the stomach.
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PMID:Acid acclimation by Helicobacter pylori. 1628 92

The objectives of this study were to evaluate the methods used to diagnose Helicobacter pylon infection in gastric biopsies, and to evaluate the correlation between H. pylori infection and clinical outcomes. Gastric biopsies, obtained from 210 patients, were evaluated for H. pylori by culture, a commercial rapid urease test (RUT, Pronto Dry) and histological examination. A true positive result was either the culture or both the RUT and histological examination were positive. The results showed a H. pylori infection rate of 44.3% (93/210). The sensitivities, specificities, positive predictive values and negative predictive values were 88.2, 100, 100, and 91.4 % by the culture; 95.7, 98.3, 97.8, and 96.6% by RUT; and 96.8, 59.8, 59.8, and 65.7% by histological examination, respectively. The prevalences of H. pylori in non-ulcer dyspepsia (NUD), peptic ulcer dyspepsia (PUD) and gastric cancer (GCA) patients were 41.2, 57.9 and 70.6%, respectively. The chi-squared-test showed that GCA patients were significantly more frequent infected with H. pylori than NUD patients (p<0.05). Our study indicates that the RUT method was highly sensitive, specific and appropriate for routine clinical use.
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PMID:Detection of H. pylori in dyspeptic patients and correlation with clinical outcomes. 1629 46

Helicobacter pylori is one of the most common bacterial infections worldwide. It is associated with chronic gastritis, peptic ulcer disease and constitutes a major risk factor for gastric adenocarcinoma and lymphoma. The aim of this study was to evaluate the specific serologic immunoglobulin G (IgG) response to whole cells proteins, CagA and urease antigens of Helicobacter pylori in a Venezuelan population. We evaluated 66 patients from the Hospital Universitario de Caracas, attending in the gastroscopy service. H. pylori infection was detected by culture and rapid urease test. IgG antibodies against, CagA and ureases were tested by enzyme-linked immunosorbent assay method using highly purified recombinant antigens. We demonstrated the presence of H. pylori in 48/66 (72.7%), by culture and rapid urease test. We found a seroprevalence of 45 (68%) to whole cells, 34/66 (51%) to CagA and 18/66 (27%) to urease. The positive rates of CagA antibodies in patients with gastric ulcer, gastric cancer and chronic gastritis were 87.8%, 77.7% y 40.8% respectively. The serum antibodies anti-CagA were similar between peptic ulcer disease and gastric cancer patients.
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PMID:[Importance of IgG anti-CagA antibodies of Helicobacter pylori in Venezuelan patients with gastric diseases]. 1635 43

Infection with Helicobacter pylori may be associated with a variety of gastroduodenal diseases. Although H. pylori infection is common, peptic ulcer disease and gastric cancer occur in only a small minority of infected persons. This work was intended to correlate the pathological findings with the serological response to certain H. pylori antigens. Serum samples were taken from 285 patients who underwent gastroscopy. H. pylori infection was diagnosed by histology, culture or rapid urease test (RUT). Serum IgG reactivity against H. pylori-specific antigens was studied by Western blot. There was a significant association between the diagnosis of gastric cancer and the presence of IgG antibodies against the 19.5, 33 and 136 kDa (CagA) antigens. Comparing all H. pylori-positive patients with the gastric cancer group for the presence of the 19.5, 33 and 136 kDa (CagA) antigens, the results were as follows: chi2: 17.482, p < 0.001, power P = 0.994, odds ratio (OR) for the presence of gastric cancer: 19.5 (95% confidence interval (CI): 4.11-92.56). Antibodies against CagA alone or other bands (except 33 and 19.5 kDa antigens), as well as the age of patients were not related to a diagnosis of gastric cancer. Male patients were more likely to develop duodenal ulcer. IgG antibodies against the 19.5, 33 and 136 kDa (CagA) antigens could be helpful to identify patients at enhanced risk for the development of gastric cancer.
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PMID:Serum antibody positivity for distinct Helicobacter pylori antigens in benign and malignant gastroduodenal disease. 1660 Jun 80

The presence of Helicobacter pylori (H. pylori) was examined in 491 sequential patients, complaining mainly of epigastric pain, by three biopsy-based methods (rapid urease, histology, and culture), and by a serological test, enzyme immunosorbent assay, (ELISA). H. pylori was detected in 341 (70%) of 491 patients examined by histology, 287 (59%) by rapid urease test, whereas 385 (78%) were seropositive for H. pylori immunoglobulins by ELISA. None of the test methods used was independently sufficient to make an etiologic diagnosis of H. pylori infection. The endoscopic findings revealed that 315 (69%) of 456 patients with non-ulcer dyspepsia, 17 (74%) of 23 patients with duodenal ulcer, 7 (78%) of 9 patients with gastric ulcer, and 2 (67%) of 3 patients with gastric cancer were H. pylori positive. No statistically significant correlation was found between the endoscopic and the histopathological findings. A significant correlation was found between H. pylori infection and the histopathological gradings of gastritis (P < 0.001).
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PMID:Helicobacter pylori infection at a university hospital in Saudi Arabia: prevalence, comparison of diagnostic modalities and endoscopic findings. 1675 59


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