Increased cell proliferation of the gastric mucosa in first-degree relatives of gastric carcinoma patients

Evaluation of apoptosis along with BCL-2 and Ki-67 expression in patients with intestinal metaplasia

The primary aim is to compare individuals with intestinal metaplasia (IM), chronic active gastritis (CAG), and normal gastric mucosa (NGM) in terms of apoptosis, proliferation, and Bcl-2 expression. The secondary aim is to determine whether these parameters are different between patients with and without gastric cancer in first-degree relatives. We enrolled 106 patients whose histopathological results were consistent with IM (n: 42), CAG (n: 51), or NGM (n: 13). Antral biopsies were immunohistochemically stained for Bcl-2 and Ki-67 expression. Apoptosis was detected using TUNEL assay. While no significant difference was determined between three groups with regard to apoptosis and Bcl-2 expression (p>0.05), Ki-67 expression was significantly higher in the IM group when compared with the CAG and NGM groups (29.90±22.87 vs. 18.18±16.22 vs. 18.54±20, respectively; p=0.012). Helicobacter pylori was determined to increase apoptosis (49.3% vs. 25.7%, p<0.05), nevertheless, it had no significant effect on proliferation and Bcl-2 expression. Bcl-2 and Ki-67 expression and apoptosis were not different among patients with and without a history of gastric cancer in first degree relatives. Although intestinal metaplasia cases demonstrate an increase in proliferation, no elevation is observed in apoptosis. This can be an important factor in the progression to gastric cancer.

Family history of cancer and stomach cancer risk

A family history of stomach cancer in first-degree relatives increases the risk of stomach cancer, but uncertainties remain as concerns the variation of the risk according to age, sex and type of relative, as well as on the role of family history of other cancers. We investigated the issue using data from a multicentric case-control study conducted in Italy between 1997 and 2007 on 230 cases aged not more than 80 years, with histologically confirmed incident gastric cancer and 547 controls admitted to hospital for acute, non neoplastic conditions. Logistic regression models adjusted for the effect of sex, age, year of interview, education, body mass index (BMI), tobacco smoking and number of brothers and sisters were used to estimate the odds ratios (OR) of stomach cancer. Relative to subjects with no history, those with a family history of gastric cancer had an OR of 2.5 (95% confidence interval (CI) 1.5-4.2). No significant heterogeneity emerged according to sex or age of the proband or of the affected relative, or smoking habits, BMI and education of the proband. As suggested from previous studies the OR was higher when the affected relative was a sibling (OR=5.1, 95% CI: 1.3-20.6) rather than a parent (OR=2.2, 95% CI: 1.2-3.9), although the heterogeneity test was not significant. The risk of stomach cancer was not increased in subjects with a family history of cancer at any other site. The OR for all sites excluding stomach was 1.0 (95% CI: 0.7-1.4).

Risk assessment in relatives of gastric cancer patients: hyperproliferation, genetics, and Helicobacter pylori infection

Approximately 10% of cases of gastric cancer present with some kind of familial aggregation, but only 1-3% of gastric carcinomas arise as a result of clearly defined genetic syndromes that require genetic counselling and aggressive preventative measures. In the remaining families, no specific abnormalities, either genetic, biochemical or histological, responsible for the increased risk have been identified. However, several lines of evidence suggest that the increased cancer risk in first-degree relatives of gastric cancer probands is mostly dependent on Helicobacter pylori infection clustering.

Gastric epithelial cell proliferation and ras oncogene p21 expression in first-degree relatives of gastric cancer patients: a case-control study

OBJECTIVES

Individuals with a family history of gastric cancer have an increased risk of developing such neoplasia. This study aimed to assess epithelial cell proliferation and ras oncogene mutation in such individuals.

METHODS

Twenty dyspeptic, first-degree relatives of patients with gastric cancer and 20 matched controls were enrolled. Endoscopy with biopsies was performed in all cases. Gastric specimens were used to look for Helicobacter pylori infection and to assess both epithelial cell proliferation and ras oncogene expression by immunohistochemistry.

RESULTS

Cell proliferation values were not significantly different between the patient and control groups (18.1 +/- 7.1 versus 18.9 +/- 7.4; P = 0.7). Overall, ras mutation was detected in five out of 40 cases, and its distribution was similar between patients and controls (20 versus 10%; P = 0.9), as well as between H. pylori-positive and negative patients (22 versus 9%; P = 0.2). Cell proliferation values tended to be higher in cases with ras mutation than in those without (25.2 +/- 9.4 versus 16.8 +/- 5.8; P = 0.08). Cell proliferation values were significantly higher in H. pylori-positive cases compared with uninfected cases, in both patient (24.7 +/- 4.7 versus 12.5 +/- 2.4; P = 0.0003) and control (25.9 +/- 4.8 versus 13.3 +/- 2.8; P = 0.0003) groups.

CONCLUSIONS

Both gastric cell proliferation values and ras mutation prevalence did not differ between first-degree relatives of gastric cancer patients and controls. H. pylori infection similarly increased the proliferation index of gastric mucosa in both groups.

Does ursodeoxycholic acid change the proliferation of the colorectal mucosa? A randomized, placebo-controlled study

BACKGROUND

In animal models ursodeoxycholic acid (UDCA) showed a chemoprotective effect against colon cancer. To explain this, a reduced proliferation of the colorectal mucosal proliferation was suggested. We, therefore, examined the influence of UDCA on the proliferation of normal colorectal mucosa in humans.

METHODS

Following endoscopic polypectomy, 20 patients with colorectal adenomas were randomized to receive either UDCA (750 mg/day, n = 10, group A) or placebo (n = 10, group B) for 6 months in a double-blinded way. Colorectal biopsies were sampled before and at the end of the medication by total colonoscopy. Colorectal mucosal proliferation was measured by FACScan analysis of propidium iodine labeling. Serum was sampled, and serum bile acids were analyzed by gas chromatography.

RESULTS

The proliferation rates at the end of the study were similar in both groups (median 15.4%; range 12.0-20.9 in group A; median 16.0%, 14.0-20.2 in group B, p = 0.41). Serum lithocholic acid levels at the end of the study were significantly higher in group A (1.3 micromol/l, 0.9-1.8) than in group B (0.7 micromol/l, 0-1.7, p < 0.02), whereas serum deoxycholic acid levels were similar in both groups.

CONCLUSIONS

In this study, UDCA treatment for 6 months does not seem to induce changes in the proliferative behavior of the colorectal mucosa in patients with adenomas. It seems likely that a putative chemopreventive effect of UDCA in humans is not exerted by a reduction of the colorectal proliferation.

Family history and the risk of stomach cancer death in Japan: differences by age and gender

Familial aggregation of stomach cancer has long been observed. The effect on disease risk of family history and its magnitude according to the type of affected relatives, however, is not well known. We conducted a prospective analysis using the JACC study (Japan Collaborative Cohort Study For Evaluation of Cancer Risk, sponsored by Monbusho) data. During the follow-up period, 662 stomach cancer deaths were documented. A positive history of stomach cancer in one or more first-degree relatives was associated with a significantly increased risk of death from the disease in both men (RR 1.60; 95% CI 1.11-2.31) and women (RR 2.47; 95% CI 1.50-4.06). In the subanalysis stratified by age, the association between positive family history and stomach cancer was stronger in the age group from 40-59 (RR 2.62; 95% CI 1.34-5.11 for men and RR 5.88; 95% CI 2.70-12.82 for women) than in the age group from 60-79 (RR 1.31; 95% CI 0.84-2.05 for men and RR 1.44; 95% CI 0.72-2.88 for women). In the age group from 40-59, men with father's history and women with mother's and sister's history of the disease had a significantly increased risk (RR 3.14; 95% CI 1.51-6.55, RR 10.46; 95% CI 4.54-24.12, RR 13.39; 95% CI 3.89-46.12, respectively). When 2 or more family members were affected, the increment in the risk was prominent especially in women (RR 9.45; 95% CI 4.46-20.05). These results suggest the existence of a certain subtype of stomach cancer that is inherited more often by women from one generation to the next in gender-influenced fashion. Any preventive strategy should take into account the degree of individual susceptibility.

Treatment of Helicobacter pylori infection. Indications and regimens: an update

The management of Helicobacter pylori infection is still surrounded by controversy and uncertainties. Indications and correct application of current regimens for Helicobacter pylori infection are still considered a matter of debate. Regarding indications, only peptic ulcer and mucosa associated lymphoid tissue lymphoma are considered clear indications for treatment. In other conditions, such as atrophic gastritis, post gastric cancer resection, first-degree relatives of gastric cancer patients, dyspeptic patients, patients with gastro-oesophageal reflux disease and non-steroidal anti-inflammatory drug users, the value of Helicobacter pylori eradication is still controversial. The regimens for first-line and second-line treatment of Helicobacter pylori infection have been recommended by the Maastricht 2 Consensus Report. Although all the treatments are considered to be effective, physicians still do not agree on what first-line regimen should be used. Furthermore, a consensus on the duration of the antibiotic treatment is still lacking, although Maastricht guidelines for treatment of Helicobacter pylori infection recommend a one-week therapy. Also regimens, as a third-line treatment, and methods to improve compliance and clinical outcome are still a matter of debate. All these points will be considered in the present review

Atrophy-metaplasia-dysplasia-carcinoma sequence in the stomach: a reality or merely an hypothesis?

The results of recent investigations have suggested that the old hypothesis of an atrophy-metaplasia-dysplasia-carcinoma sequence in the stomach needs to be qualified. The most common cause of intestinal metaplasia is Helicobacter pylori gastritis. The consequence of this intestinal metaplasia is focal atrophy. Helicobacter pylori infection may also trigger an autoimmune gastritis of the corpus mucosa, with atrophy and intestinal metaplasia. Most intestinal metaplasias are only 'paracancerous' but not 'precancerous' lesions. Diffuse gastric carcinomas, such as the signet ring cell carcinoma, arise independently of intestinal metaplasia. Histogenetically, numerous carcinomas of the stomach are primarily of the gastric type, and may secondarily change into the intestinal type.High-grade intra-epithelial neoplasias (dysplasias) detected during the biopsy-based diagnostic work-up appear to be a marker for carcinoma and must, therefore, be removed endoscopically. The detection of intestinal metaplasia in routinely obtained biopsy material is subject to sampling error and is, therefore, not a suitable marker for an increased risk of a gastric carcinoma developing. As an alternative, the concept of gastritis of the carcinoma phenotype, which is more frequently found in early gastric carcinomas and in the relatives of gastric carcinoma patients, has been developed. In this concept, the diffuse parameters of grade and activity of the gastritis in the antrum and corpus, which are independent of sampling error, are subjected to a comparative analysis. A risk gastritis of the carcinoma phenotype is diagnosed when the grade and activity of the gastritis in the corpus are at least equally as pronounced as in the antrum. Currently, this concept is being tested in a prospective ongoing study. Future studies must show whether, and if so which, immunohistochemical or molecular-genetically detectable changes can be applied as risk markers in the diagnostic work-up. Helicobacter pylori eradication probably does not lead to complete regression of the intestinal metaplasia and ensuing focal atrophy. However, eradication of H. pylori does lead to the normalization of changes that can lead to mutations of the stem cells of the gastric mucosa (free radicals, nitric oxide, cell proliferation and vitamin C secretion).

Helicobacter pylori infection: protection against Barrett's mucosa and neoplasia?

BACKGROUND

Since Helicobacter pylori (Hp) infection provokes intestinal and gastric metaplasia, the question arises whether the specialized metaplasia (Barrett's mucosa (BM)) and dysplasia or carcinoma in Barrett's epithelium seen in gastro-oesophageal reflux disease (GORD) might not also be correlated with Hp infection, or whether the latter offers protection against Barrett's oesophagus and Barrett's adenocarcinoma.

PATIENTS

Gastric and oesophageal biopsies obtained from a total of 2,201 patients were analysed retrospectively. 297 of these patients had GORD (age 53.5 +/- 13.4 years; m:f ratio 2.1:1), 1,192 patients had BM (age 62.8 +/- 14.6 years; m:f 2.3:1) with or without neoplasia. 1,054 of these patients were diagnosed as having BM alone, 138 patients having BM neoplasia (high-grade dysplasia or adenocarcinoma). Patients with BM and low-grade dysplasia were excluded from this study because of the uncertainty in differentiating low-grade dysplasia from regenerative epithelium. A total of 712 patients with non-ulcer dyspepsia (NUD; average age 40.0 +/- 16.1 years; m:f 0.3:1) served as a control group.

RESULTS

The percentage of Hp infection did not differ between patients with GORD with (53.3%)/without BM (51.4%) and neoplasia (47.8%), but is statistically significantly lower than in patients with NUD (65.7%).

CONCLUSION

Our analysis shows that patients with GORD and Hp infection have no increased risk for the development of BM or neoplasia in BM. Since Hp infection is significantly less frequent in GORD than in NUD patients, a protective effect of the Hp infection is a possibility worth discussing.

Expression of transforming growth factor beta-1 in gastric cancer and in the gastric mucosa of first-degree relatives of patients with gastric cancer

Transforming growth factors beta (TGF-beta) constitute a family of polypeptide growth factors that control cell growth, cell differentiation and migration, as well as the formation of the extracellular matrix. Recent analyses revealed the overexpression of TGF-beta1 in human gastric cancers and demonstrated increased cell proliferation in the stomach of patients with gastric cancer and their first-degree relatives. Using human gastric tissues obtained from patients with gastric cancer (n = 19), biopsies from healthy first-degree relatives of gastric cancer patients (n = 18) and healthy individuals (n = 19), we analysed the expression of TGF-beta1 using the reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry. Fifteen of 19 patients with gastric cancer expressed TGF-beta1 in the tumour. In 11 of these 15 cases TGF-beta1 mRNA was also detectable in the non-tumourous stomach. Interestingly, all but two individuals with a first-degree relative diagnosed with gastric cancer exhibited TGF-beta1 expression in either the antrum or corpus biopsy or both. In contrast, only one of 19 individuals without a family history of gastric cancer expressed TGF-beta1 in the stomach (P< 0.0001). TGF-beta1 expression is detectable in a large proportion of gastric cancers and in the stomach of healthy first-degree relatives of gastric cancer patients. Since individuals without gastric cancers in their family express TGF-beta1 only in one of 19 cases, the induction of TGF-beta1 expression in first-degree relatives of patients with gastric cancer points to the presence of specific molecular alterations in a subgroup of individuals with an increased risk of developing gastric cancer that may precede the development of gastric cancers.

Frequency of TPR-MET rearrangement in patients with gastric carcinoma and in first-degree relatives

BACKGROUND

The activation of the c-met protooncogene through a rearrangement has been detected previously in gastric carcinoma tissue and precancerous lesions. In the current study the authors analyzed the rearrangement of TPR-MET in gastric carcinoma patients and in first-degree relatives to evaluate the potential role and timepoint of this genetic alteration in the process of gastric carcinogenesis and its potential value in identifying those individuals with an increased risk of developing gastric carcinoma.

METHODS

The presence of TPR-MET mRNA was determined in gastric tissue from 19 patients with gastric carcinoma and in the gastric mucosa of 18 first-degree relatives without gastric carcinoma and in the gastric mucosa of 18 first-degree relatives without gastric carcinoma using a nested reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern blot analysis. A 205-base pair (bp) cDNA fragment and a 70-bp cDNA fragment spanning the breakpoint were amplified by nested PCR. Amplification products were hybridized with an oligonucleotide labeled at the 3'-end with DIG-11-dUTP spanning the breakpoint using Southern blot analysis. The MNNG-HOS cell line served as a positive control.

RESULTS

TPR-MET mRNA was detected in nine gastric carcinoma patients (47%). Among these patients, TPR-MET mRNA was present in the both tumor and tumor free tissues in 5 patients (26%), in the tumor tissue only in 2 patients (11%), and in the tumor free gastric mucosa only in 2 patients (11%). It is interesting to note that TPR-MET rearrangement also was detected in the gastric corpus mucosa of 1 first-degree relative (6%), but in none of the control subjects.

CONCLUSIONS

The data from the current study indicate that TPR-MET activation may be an early event in gastric carcinogenesis and may be useful for the identification of individuals with an increased risk of developing gastric carcinoma.

Host determinants of Helicobacter pylori infection and its clinical outcome

Greater than one-half of the world's population harbors Helicobacter pylori. The majority of infected individuals, however, remain asymptomatic, with only 10% to 20% developing diseases, including peptic ulcer disease, gastric cancer, and gastric mucosa-associated lymphoid tissue lymphoma. This article reviews host factors that may predispose an individual to both the acquisition of H. pylori infection and subsequent clinical outcome. Individuals with specific blood group antigens and human leukocyte antigen genotypes may be more susceptible to H. pylori infection. Additional factors, such as the age of acquisition, the host immune response, the site of infection, acid secretion, and interactions with nonhost factors (including bacterial virulence factors and environmental influences) may play a role in determining clinical outcome. Further investigation is required to clarify the mechanisms by which these interactions occur and, more critically, to determine their relative importance. This knowledge will enable the identification of individuals at risk of developing clinical disease with H. pylori infection.