Krzysztof Marlicz

Expression of survivin and caspase-3 in gastric cancer.

Gastric cancer is one of the most common malignant tumors of the gastrointestinal tract. However, the molecular pathways involved in the regulation of gastric carcinogenesis are not completely elucidated. In the last decade, basic cancer research has been focused on the deregulation of apoptosis as a central event in the process of carcinogenesis. Caspase-3 and survivin are regulators of apoptosis and have been implicated in the development of gastric cancer. The aim of the present study was to compare the expression of mRNA and protein for survivin and caspase-3 in the gastric cancer and in the cancer margin with that in normal human gastric mucosa. Fifteen patients with advanced gastric cancer (all H. pylori-positive) and 15 matched control subjects with normal gastric mucosa were included in this study. The biospy specimens for histology and for molecular analyses were taken from gastric tumor, tumor surrounding gastric mucosa and in normal patients from the mucosa of antrum and corpus. Survivin mRNA expression was very weak, but detectable, in the normal gastric mucosa. However, at the protein level, no expression for survivin was detected in the normal gastric mucosa. In the biopsy specimens from tumor and surrounding gastric mucosa, a significant increase in survivin mRNA and protein expression was observed. The expression of survivin was higher in the tumor than in the tumor margin. The mRNA and protein expression of caspase-3 was detected in the gastric mucosa of normal subjects. In gastric cancer only the expression of procaspase-3 was observed, while the expression of active caspase-3 was completely undetectable. In the gastric mucosa surrounding gastric cancer, no gene and protein expression for caspase-3 was detected. We conclude that the changes in the level of caspase-3 and survivin play an important role in the transformation from normal gastric mucosa to gastric career.

Expression of hepatocyte growth factor, transforming growth factor alpha, apoptosis related proteins Bax and Bcl-2, and gastrin in human gastric cancer

Gastric cancer is one of the most frequent neoplasms and a leading cause of the death world‐wide. In recent years, epidemiological and animal studies demonstrated a link between gastric cancer and chronic infection with H. pylori. The exact mechanism responsible for the development of gastric cancer in H. pylori‐infected patients still remains unclear. There is evidence that the up‐regulation of certain growth factors could play an important role in the promotion of the gastric carcinogenesis.

5T4 oncofetal antigen in gastric carcinoma and its clinical significance.

Objective To evaluate the role of 5T4 antigen in gastric cancer progression and prognosis. Design A prospective study of 5T4 antigen expression in primary, secondary and recurrent gastric carcinoma, the relationship to selected prognostic parameters and the course of disease. Patients Eighty six patients operated on for gastric cancer. Tissue One hundred and twenty two gastric tumours were studied, including 86 primary carcinomas, 32 coexisting lymph node métastases and four recurrent carcinomas. Methods Immunohistochemistry using 5T4 monoclonal antibody on frozen sections. Results The 5T4 antigen was detected in 41% of primary gastric tumours including early gastric cancer. A strong relationship was found between 5T4 positivity and tumour histology. Thus, 52% of gastric carcinomas of intestinal type expressed 5T4 antigen compared with 28% of the diffuse type (P= 0.028). Among 16 sets of primary gastric carcinomas and regional lymph node métastases, coordinate 5T4 expression was seen in 14 cases; the other two showed acquisition of positivity on metastatic tumour cells (carcinomas of diffuse type). 5T4 antigen was detected more frequently in carcinomas with p53 accumulation compared with those with undetectable p53 levels (P=0.015). The presence of 5T4 in cancer cells was correlated with poor short-term prognosis (24% vs 49% of 2 year survival for 5T4 positive and negative tumours respectively, P= 0.024). The effect on survival was evident in the p53 negative group, with patients 5T4 positive showing worse survival (28% vs 60% in 2 years). Conclusions Our results suggest that the assessment of 5T4 expression in gastric carcinoma can be helpful in identifying patients with poor short-term prognosis.

The clinical significance of p53 accumulation in gastric carcinoma

Alterations in the expression of p53 tumor suppressor protein is a frequent event in human cancer but the practical implications of this phenomenon are yet to be fully exploited. The objective of this study was to determine the value of p53 accumulation as a marker of tumor progression and prognosis of gastric carcinoma patients and to evaluate whether this parameter can be properly assessed prior to surgery.

Helicobacter pylori and CagA status, serum gastrin, interleukin-8 and gastric acid secretion in gastric cancer.

Background: Despite numerous epidemiological studies, the association between Helicobacter pylori infection and gastric cancer (GC) remains unexplained. This study was designed to determine the seropositivity of H. pylori and cytotoxin-associated gene A (CagA), serum gastrin and interleukin-8 (IL-8) levels as well as basal intragastric pH and maximal histamine-induced gastric acid outputs (MAO) in a large series of GC patients and controls. Methods: 337 GC patients (118 men and 219 women; median age 59.4; range 21-87) and 337 controls randomized for sex and age entered the study. Serum IgG antibodies to H. pylori and CagA and serum levels of IL-8 were measured by enzyme-linked immunosorbent assay, while serum-amidated gastrin was determined by specific radioimmunoassay and correlated with gastric luminal pH. Results: The numbers of GC patients and controls involved in the study in various age groups, ranging from 20 to >70 years, were similar, but overall H. pylori IgG seropositivity in GC patients was significantly higher (90.8%) than in controls (79.2%). The overall CagA seropositivity in GC patients was about double (58.2%) that in controls (25.2%). Serum gastrin levels over the calculated cut-off value (38.88 pM/L) were found in several-fold larger number in GC patients (48%) than in controls (8.3%) and, similarly, serum IL-8 values over the cut-off point (1.77 pg/mL) occurred in almost all (99.7%) GC patients but in only a few controls (0.3%). Basal intragastric pH above the cut-off point (pH = 4.50) was observed in about 58.2% of GC patients compared to 15.1% in controls, and strong correlation between the serum gastrin and gastric pH was found in GC but weak in controls. The cut-off value for MAO was 12.3 mml/h; MAO below this cut-off value occurred in 89.9% of GC patients and in only 4.7% of controls. A summary odds ratio (SOR) in GC for H. pylori IgG was 2.59 (95% Cl; 1.61-4.22) for CagA - 4.12 (95% Cl; 2.93-5.8), for serum gastrin - 10.25 (95%; 6.47-16.47) and for MAO - 15.2 (95% Cl; 9.45-39.82). Multivariable analysis of serum gastrin, IgG and CagA, and luminal pH and MAO values revealed that only gastrin and CagA have significant influence on GC formation (OR >1 in logistic regression). Conclusions: 1. CG patients show significantly higher H. pylori IgG and CagA seropositivity than dyspeptic age- and gender-matched controls, confirming that gastric infection with CagA expressing H. pylori greatly increases the risk of GC. 2. Serum gastrin levels in GC but not in controls are correlated with the rise in intragastric pH, indicating that excessive gastrin release in GC is affected by lower intragastric pH. 3. Serum gastrin level and CagA seropositivity are significantly increased in the majority of GC patients, and are the only variables in multivariable analysis to have a predominant influence on GC formation, which suggests that both these parameters may be implicated in H. pylori -related gastric carcinogenesis. 4. H. pylori -infected GC patients produce significantly more IL-8 than do non-GC controls, probably reflecting CagA-positive H. pylori -associated gastritis.

Helicobacter pylori–gastrin link in MALT lymphoma

There is accumulating evidence for the role of Helicobacter pylori in the development of gastric cancer as well as of lymphomas that arise in mucosa‐associated lymphoid tissue (MALT). We reported recently that gastric cancer patients show high prevalence of cagA‐positive H. pylori and express gastrin and gastrin receptors enabling them to stimulate tumour growth in autocrine fashion.

Progastrin and Cyclooxygenase-2 in Colorectal Cancer

Colorectal cancers (CRCs) are one of the most common forms of cancer in Poland and one of the leading causes of death. The tumors have been attributed to genetic, dietary, and other environmental factors, but recently growth factors such as gastrin have also been implicated in the carcinogenesis. The relationship between plasma amidated and nonamidated gastrin in CRCs is controversial. This study was designed (1) to determine the plasma levels of progastrin and amidated gastrin in 50 CRC patients before and 3–6 months after removal of the tumor, (2) to determine the tumor concentrations of these gastrin peptides and the level of expression for gastrin mRNA and gastrin/CCKB receptor mRNA, (3) to examine the expression of cyclooxygenase COX-1 and COX-2 mRNA in CRC tissue, and (4) to compare the prevalence of Hp and its cytotoxic protein, CagA, and cytokines (TNFα, IL-1β, and IL-8) in CRCs, before and after removal of tumor. It was found that the CRC, its resection margin, and the plasma contained severalfold higher levels of progastrin than of amidated gastrins and that the removal of the CRC tumor resulted in a marked reduction in plasma progastrin level without a significant alteration in plasma levels of amidated gastrins. Both gastrin and CCKB-R mRNA were detected in the cancer tissue and resection margin by RT-PCR, and similarly, COX-1 and COX-2 mRNA were expressed in these tissues of most CRCs. The seroprevalence of Hp, especially that expressing CagA, and levels of IL-1β, but not other cytokines, were significantly higher in CRC patients than in 100 age-, gender-, and profession-matched controls and did not change significantly about 3–6 months after tumor resection. We conclude that (1) the CRC and its margin contain large amounts of progastrin and show gene expression of gastrin, CCKB-R, and COX-2; (2) removal of the CRC markedly reduces the plasma concentrations of progastrin; (3) the Hp infection rate is higher in CRC, and this may contribute to colorectal cancerogenesis via enhancement of progastrin and gastrin release; and (4) plasma progastrin concentrations might serve as a biomarker of CRC.

Seroprevalence of Helicobacter pylori infection in Polish children and adults depending on socioeconomic status and living conditions

PURPOSE Helicobacter pylori (H. pylori) is one of the causes of gastritis, peptic ulcer disease, gastric cancer and MALT-lymphoma. The frequency of H. pylori infection is different in various regions of the world and dependent on age, socioeconomic and hygiene status. The objective of this study was to assess seroprevalence and the associated socioeconomic and sociodemographic characteristics influencing H. pylori infection in children and adults in Polish population. MATERIAL/METHODS In multicenter epidemiological studies, H. pylori infection occurrence was assessed in Poland in the years 2002 and 2003. The seroprevalence of H. pylori infection diagnosis was based on IgG anti-H. pylori antibodies concentration above 24 UI/ml, which was measured using ELISA test. The study included 6565 subjects: 3307 adults (50.37%) and 3258 children (49.63%). RESULTS Positive result was observed in 3827 subjects (58.29%), i.e. 1043 children (32.01%) and 2784 adults (84.19%). H. pylori infection prevalence was greater in children of poor economic status, who were born in a rural area, lived in crowded houses with no running tap water and with toilet outside the house, and who did not observe hygiene rules. In adults, the factors predisposing to higher probability of being H. pylori infected included: being born in a rural area, having low family income and elementary education, smoking tobacco, drinking high proof alcohols as well as not observing of hygiene rules. CONCLUSIONS Improvement of socioeconomic status, sanitary and hygienic conditions and the education of the society might decrease H. pylori infection prevalence in children and in adults.

The Association Between the Interleukin-1 Polymorphisms and Gastric Cancer Risk Depends on the Family History of Gastric Carcinoma in the Study Population

OBJECTIVES:The association between interleukin-1 polymorphisms, H. pylori and increased gastric cancer risk remains controversial.AIMS:To compare the prevalence of these polymorphisms in individuals with two mutually exclusive diseases connected with infection, gastric cancer, and duodenal ulcer.METHODS:121 gastric cancer and 119 duodenal ulcer patients. Genomic DNA was typed for polymorphisms at position −511, −31 in the interleukin-1β gene (IL-1 β) using primer extension and mass-spectrometry. Analysis of the variable number of tandem repeats in intron 2, in its receptor antagonist gene (IL-1RN) was performed by PCR and agarose gel electrophoresis.RESULTS:All subjects were successfully genotyped for the three gene loci. IL-1 β-511 was found to be in reverse linkage disequilibrium with IL-1 β-31. The differences between gastric cancer and duodenal ulcer patients concerned only heterozygous variant of IL-1β and were related to family history of gastric cancer, tumor stage, histology, site. Thus, CT carriers were found to have a higher risk of sporadic [OR 2.21 (95% CI, 1.22–3.99)], early [OR 2.81 (95% CI, 1.14–6.93)], diffuse [OR 2.48, (95% CI 1.21–5.09)] or non-cardia gastric cancer [OR 1.88 (95% CI 1.06–3.33)]. Furthermore, CT genotype was significantly more prevalent in gastric cancer patients with negative than in those with a positive family history (p = 0.039).CONCLUSIONS:The association between the interleukin-1 polymorphisms and gastric cancer risk depends on the family history of gastric carcinoma in the study population. This phenomenon may be in part responsible for differences in results of interleukin-1 studies performed on populations with low and high gastric cancer prevalence.

Increased PCNA/cyclin index correlates with severity of duodenitis defined by histological criteria

The proliferative activity of crypt epithelial cells was studied in 64 duodenal biopsies using immunohistochemistry and proliferating cell nuclear antigen (PCNA)/cyclin monoclonal antibodies in alcohol-fixed paraffin-embedded sections. A positive correlation between duodenitis as defined by histological criteria and increased mean percentage of PCNA positive crypt cell nuclei (PCNA index) was found. The mean PCNA index in normal mucosa was 11.8±2.7% (mean ± SD), in mild (grade 1) duodenitis 17.3±3.9%, in moderate (grade 2) 30.6±6.9%, and in severe (grade 3) duodenitis 41.1±8.5%. The inclusion of PCNA index, which is easily measured in paraffin-embedded sections, in the existing histopathological grading systems of duodenitis may improve their clinical relevance.