Gastric hyperplastic polyps coexisting with early gastric cancers, adenoma and neuroendocrine cell hyperplasia.

Gastric hyperplastic polyps (GHP) constitute up to 93% of all benign epithelial polyps of the stomach. The average probability of malignant transformation in GHP is 0.6-22% in large series. The aim of the study was to present the coexistence of GHP with early gastric cancer (EGC), gastric adenoma (GA), neuroendocrine cell hyperplasia (NH) and well-differentiated neuroendocrine tumour (NET G1). Three cases were studied to reveal clinical data and morphological changes and to assess the relationship between GHP and accompanying gastric neoplastic lesions.

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.

Molecular basis of colorectal cancer - role of gastrin and cyclooxygenase-2.

BACKGROUND: Tumors arising in the colorectal area have worldwide distribution and concern mostly older population being attributed to genetic, dietary and hormonal factors but most recently also to infection with Helicobacter pylori (HP). Both, HP discovery and molecular biology of colorectal cancer have been recently considered as two of ten greatest advances of gastroenterology at the dawn of 3rd millenium but little information is available regarding the relationship between the HP and colorectal cancer. Since HP infection is usually accompanied by an increase in plasma level of gastrin, which is also recognized as a trophic hormone for the colonic epithelium and a potent mitogen capable to induce cyclooxygenase-2 (COX-2), we decided 1) to compare the seroprevalence of HP, its cytotoxic protein, CagA, and cytokines (TNFalpha, IL-1beta and IL-8) in colorectal cancer patients, before and after removal of cancer, with those in age- and gender-matched controls; 2) to determine the gene expression of gastrin and gastrin receptors (CCK(B)-R) in colorectal cancer tissue, 3) to assess the plasma levels and tumor tissue contents of gastrin, 4) to examine the mRNA expression of cyclooxygenase COX-1 and COX-2 cancer tissue and intact colonic mucosa. MATERIAL AND METHODS: The trial material included 80 patients with colorectal cancers and 160 age- and gender-matched controls. Anti-HP IgG, anti-CagA IgG seroprevalence and cytokine levels were estimated by ELISA tests. Gene expressions of gastrin, CCK(B)-R, COX-1, COX-2 and Bax and Bcl2 was examined using RT-PCR, while gastrin was measured by RIA. RESULTS: The HP IgG seroprevalence, especially that expressing CagA, was significantly higher in colorectal cancer patients than in controls and did not change one week after tumor resection while plasma cytokines were significantly reduced after this operation. Gastrin and CCK(B)-R mRNA were detected in the cancer tissue and the resection margin and similarly COX-2 mRNA was expressed in most of cancers and their resection margin but not in intact colonic mucosa where only COX-1 was detected. The colorectal cancer tissue contained several folds more immunoreactive gastrin than cancer resection margin and many folds more than the intact colonic mucosa. CONCLUSIONS: 1) Colorectal carcinoma and its resection margin overexpress gastrin and receptors for gastrin (CCK(B)-R), and COX-2; 2) here, we propose that an increased plasma level of gastrin should be considered as suitable biomarker of colorectal cancer, 3) HP infection may contribute to colonic cancerogenesis by enhancing expression of gastrin and COX-2, they may account for stimulation of the tumor growth, angiogenesis and reduction in apoptosis as evidenced an increased ratio of mRNA expression for anti-apoptotic Bcl2 over proapoptotic Bax proteins and 4) HP positive patients who develop colorectal cancer should be subjected to the HP eradication; this is expected to reduce hypergastrinemia and to attenuate COX-2 expression. Our final conclusion would be: treatment of patients with colorectal cancer with COX-2 selective inhibitors now gained a strong support as a preventive measure.

Helicobacter pylori infection, gastrin, cyclooxygenase-2, and apoptosis in colorectal cancer.

Helicobacter pylori (HP) infection is usually accompanied by an increased plasma level of gastrin, a potent mitogen able to induce cyclooxygenase (COX)-2. This study examined (a) the seroprevalence of HP, its cytotoxic protein, CagA, and cytokines (tumor necrosis factor alpha, interleukins 1beta and 8) in 80 patients with colorectal cancers, before and after the removal of tumor, compared with 160 age- and gender-matched controls; (b) the gene expression of gastrin and its receptors (CCKB-R) in the cancer tissue, (c) the plasma levels and tumor tissue contents of gastrin, and (d) the mRNA expression of COX-1, COX-2, and apoptotic proteins (Bax and Bcl2) in cancer tissue and intact colonic mucosa. Anti-HP IgG, anti-CagA IgG seroprevalence, and cytokine levels were analyzed by enzyme-linked immunosorbent assay tests; gene expressions of gastrin, CCKB-R, COX-1, COX-2, Bax, and Bcl2 by reverse transcriptase polymerase chain reaction; and gastrin by radioimmunoassay. The seroprevalence of HP, especially that expressing CagA, was significantly higher in cancer patients than in controls and did not change 1 week after tumor resection while plasma cytokines were significantly reduced after this operation. Both gastrin and CCKB-R mRNA were detected in the cancer tissue and the resection margin; similarly, COX-2 mRNA was expressed in most of cancers and their resection margin but not in intact colonic mucosa, where only COX-1 was detected. The colorectal cancer tissue contained several folds more immunoreactive gastrin than cancer resection margin and many folds more than the intact colonic mucosa. We conclude that colon adenocarcinoma and its resection margin overexpress gastrin, its receptors, CCKB-R, and COX-2, and that HP infection may contribute to colonic cancerogenesis via overexpression of gastrin and COX-2, which may account for the stimulation of the tumor growth and the reduction in apoptosis as documented by enhanced mRNA expression of anti-apoptotic Bcl2 over proapoptotic Bax proteins.

Helicobacter pylori-gastrin link in MALT lymphoma.

BACKGROUND: 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. AIMS: Since the H. pylori infection is considered to be more strongly associated with MALT lymphoma than with gastric cancer, we decided to determine the gastrin and its receptors' mRNA expression and gastrin content in this tumour as well as the release of this hormone both into plasma and gastric lumen. Twenty MALT lymphoma patients were compared with 100 age- and gender-matched controls with similar dyspeptic symptoms. RESULTS: The overall H. pylori seropositivity in MALT lymphoma was about 90% and CagA positivity was 70%, compared to 56% and 33%, respectively, in controls. The serum gastrin in MALT lymphoma was about sixfold higher than in controls while gastric luminal gastrin in these patients was over 70 times higher than in controls. Gastrin content in tumour was about 10-fold higher than in antral mucosa. Gastrin and gastrin-receptor (CCKB-receptor) mRNA were detected by reverse transcriptase-polymerase chain reaction in cancer tissue whilst in the fundic and antral mucosa, only enhanced expression of CCKB-receptor mRNA and gastrin mRNA was detected, respectively. Histamine stimulation in MALT lymphoma induced acid secretion that was only about 30% of control value due to atrophic gastritis. This study confirms an important role of CagA-positive H. pylori in the pathogenesis of MALT lymphoma and shows that this lymphoma is capable of synthesizing and releasing potent growth promoting gastrin, possibly due to the action on G-cells of H. pylori-originated Nalpha-methyl histamine and cytokines (tumour necrosis factor alpha and interleukin-8). CONCLUSIONS: Gastric MALT lymphoma is closely linked to CagA-positive H. pylori infection. Gastrin and its receptors may be implicated in the pathogenesis of gastric lymphoma.

[Argon plasma coagulation in a patient with early diagnosis of gastric carcinoma]. / Argonowa koagulacja plazmowa u chorego z wczesnie rozpoznanym rakiem wpustu.

Argon plasma coagulation (APC) has been introduced for the local endoscopic treatment of gastrointestinal malignancy recently. It is mainly used as a palliative therapy, especially in case of stenosis. Despite a lot of publications concerning APC the clinical usefulness of this method in a small malignant tumors remains unclear. The patient with early diagnosed carcinoma of gastric, efficiently treated using argon plasma coagulation is described.

CD56(NCAM) antigen in glandular epithelium of human thyroid: light microscopic and ultrastructural study.

CD56 antigen, an isoform of the neural cell adhesion molecule (NCAM) was previously found by us in human thyroid by APAAP immunohistochemistry in light microscopy on frozen tissue sections. In the current study, it was attempted to trace the antigen in question using another light microscopic immunohistochemical procedure and to validate the results at the ultrastructural level. For light microscopy, cryostat sections of 12 surgical samples of human thyroid were subjected to ABC (preformed avidin-biotin-peroxidase complex) method. For immunoelectron microscopy, immunoperoxidase reaction was carried out on prefixed, small thyroid tissue blocks. Following preliminary inspection of semithin sections, ultrathin sections were examined in the transmission electron microscope. ABC reaction revealed distinct specific CD56 staining of thyrocyte cell membranes. The staining was weak or absent in thyroid papillary carcinoma cells. The results were confirmed in semithin sections by indirect immunoperoxidase. The latter reaction in ultrathin sections at the ultrastructural level has shown that specific reaction product was confined to free and lateral surfaces of thyroid follicular cells. Endothelial cell membranes of thyroid capillary vessels were totally devoid of the reaction product. The reaction was weakly positive in thyroid follicular and papilllary carcinomas but absent from medullary carcinoma.

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 metastases 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 metastases, 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.

Expression of CD56/N-CAM antigen and some other adhesion molecules in various human endocrine glands.

CD56/N-CAM antigen, 140 kDa isoform of neural cell adhesion molecule (N-CAM) has been previously traced by some of us in follicular epithelium of human thyroid by immunohistochemistry. The reaction product was cell membrane bound, being stronger in hyperactive thyroid as compared to colloid goiter. In the current study, CD56 was searched in other endocrine glands and their tumors including parathyroids, adrenal cortex and parafollicular C cells of the thyroid (TT cell line). The antigen was also examined in the tissue extracts of endocrine and nonendocrine organs by dot blot immunoassay and anti CD56 monoclonal antibody. Besides, some other cell adhesion molecules (CAMs) were looked for in the tissues and cells tested. It has been found that CD56 is expressed in all zones of adrenal cortex, albeit in various intensity. The reaction was cell membrane bound in cortical hyperplasia and adenoma but cytoplasmic in the carcinoma of adrenal cortex. Other endocrine tissues and cells tested were devoid of CD56. Presence of CD56 antigen could be confirmed by dot blot assay with 3M KCl and NP40 extracts of both, thyroid and adrenal glands. Apart from CD56 some other CAMs could be traced in thyroid cell membranes including CD44, VLA-3 integrin and E-cadherin, what was not the case in the adrenal cortex. In parathyroids and parathyroid adenoma, diffuse immunostaining of E-cadherin and irregular, focal expression of CD44 was observed. These results show, apart from CD56, abundance of other CAMs in the thyroid gland and their relative scarcity in other endocrine tissues tested.

Extracellular matrix proteins and VLA integrins expression in the microenvironment of human lung carcinoma.

In order to gain an insight into interactions between human cancer and the surrounding host tissues, surgical samples of lung carcinoma of distinct histological types were examined for the expression of extracellular matrix (ECM) proteins and very late antigen (VLA) integrins, by means of a panel of monoclonal antibodies and immunohistochemistry of frozen tissue sections. It has been found that fibronectin (FN), tenascin (TN) and to a lesser degree collagen IV were abundant in the immediate vicinity of the tumor, but only TN penetrated tumor mass. FN isoforms were scarce or undetectable within the tumor area. The walls of blood vessels in the vicinity of the tumor showed increased an expression of collagen IV and laminin. The latter was occasionally absent within the basal membrane of cancer cells. The expression of EMC proteins was inversely proportional to the intensity of mononuclear tumor infiltrating cells (TIC). VLA integrins were present on both types of the cells: TIC and tumor cells. Percentage of positive TIC varied from 20% to 70%, depending on VLA integrin tested. VLA-3 was demonstrated on most of the cells of squamous carcinoma, but was almost absent on those of anaplastic small cell carcinoma one. In metastatic lymph node, VLA-4 was strongly expressed on tumor cells comparing to lymphoid ones. These data show that VLA integrins and their EMC ligands play apparently an important, but still obscure role in the interactions between lung carcinoma and its host.

The search for tumor-associated proteins in pleural effusions by means of monoclonal antibodies and a dot blot assay.

Liquid moiety of 61 pleural effusions was tested for tumor-associated proteins (TAP) by means of a dot immunobinding (dot blot) assay (DIA) and a panel of monoclonal antibodies (Moabs). The sensitivity of the assay was checked using a purified, serially diluted carcinoembryonic antigen (CEA) preparation and an anti-CEA monoclonal IgG system. The latter was examined using both DIA and enzyme-linked immunosorbent assay ELISA solid phase assays in simulated conditions that mimicked the protein content of effusions. Finally, the results of DIA were compared to the immunohistochemistry carried out on cell sediments from the same effusions with similar Moabs. It was found that the prevalence of several TAPs, including CEA, epithelial membrane antigen (EMA), vimentin, tenascin, and Thomsen Friedenreich antigen, was significantly higher in the malignant effusions than in the nonmalignant ones. A total, larger than 2, of detected TAPs in a given fluid, was found almost exclusively in malignant effusions (p less than 0.0001). The detection limit of the DIA for a CEA was determined at 5 ng/ml, while for the ELISA it was 1 ng/ml. Several TAPs, especially the CEA, could be detected in parallel tests, carried out on the liquid moiety and the cell sediments of malignant effusions. The evaluation of selected TAPs in pleural effusions by dot blot assay may be of clinical value.

Alloantibodies, autoantibodies, and immune complexes in patients with lung cancer.

The sera of patients with lung cancer, nonmalignant lung disease, and blood donors were subjected to various immunologic assays. Nine assays, based on immunoradiometric (IRMA) and immunoenzymatic (ELISA) principles, included 3 types of fetal cell antibodies, 2 established lung cancer cell antibodies, anti-DNA, anti-IgG autoantibodies, and immune complex assays based on C1q binding and anti-C3 activity. Antitumor cell antibody level was significantly lower in patients with lung cancer compared to blood donors. In the remaining 7 assays, the lung cancer patients tended towards higher median values compared to both control patients and blood donors, but without statistical significance, with the exception of anti-DNA antibodies. Statistical analysis of all 9 assays taken together has shown significant differences between the 3 groups. When only 5 assays were used to assess 3 types of fetal cell antibodies, anti-DNA antibodies, and immune complexes by means of ELISA anti-C3, the margins between groups increased. A range of values for the selected assays was established that may discriminate 70% of tested individuals of the 3 groups. These results suggest the existence of a characteristic profile of deranged humoral immunity in lung cancer patients.

Incidence of alloantibodies and immune complexes in bronchial secretions of lung cancer patients.

Bronchial secretions may accumulate immunoglobulins (Igs) produced by lymphocytes infiltrating tumor and its vicinity, and tumor associated antigens to higher degree than cancer patient serum. All three classes of Igs were increased in bronchial secretions from lung cancer patients as compared to control patients. Similar relationships were found for IgG and IgA/albumin ratios and IgG and IgA indices. The level of alloantibodies to fetal cells (measured by immunoradiometric--IRMA--assay) and immune complexes (IC, measured by IRMA--Clq and ELISA--anti C3) were significantly higher in lung cancer patients versus control patients in bronchial secretions. The differences were similar in sera but they were not significant. On the contrary, alloantibody binding to tumor cells was higher in control group. Absorption experiments with normal cells abolished antitumor and antifetal activity, what indicates natural character of these alloantibodies. Significant correlations between alloantibody to fetal cells and IC levels indicate that fetal antigens may contribute to antigenic component of IC. These findings suggest the link of alloantibodies and IC levels in bronchial secretions with neoplastic growth.

Identification of a tumor-related protein antigen in immune complexes derived from pleural effusions of patients with bronchial carcinoma.

Pleural effusions from 15 patients with advanced primary bronchial carcinoma, from 2 patients with metastatic lung cancer and from 6 patients with nonmalignant disease were studied. Immune complexes were found in examined fluids in amounts corresponding to 2.5-210 mg/100 ml of aggregated IgG by means of ELISA solid phase anti C3 and 125ICIq binding radioimmunoassay. Following determination of protein content and salting out by ammonium sulfate of examined fluids, the sediments were subjected to subsequent chromatographic procedure including molecular sieving (Sephadex G-200, Sepharose 4B) and affinity chromatography on Protein A-Sepharose CL-4B. The yield--apparently pure immune complexes--was then split by means of chaotropic agent 2.5 M KSCN. It permitted to obtain 2 fractions: one contained IgG while the other was a non-Ig protein of m. w. = 150 000. The latter isolated from malignant effusions possessed antigenic activity in the leukocyte migration inhibition (LMI) assay. It resulted in inhibition of migration of allogenic peripheral blood leukocytes from lung cancer patients in 87% of cases. It had no activity against leukocytes from nonmalignant disease patients. LMI activity of the final second fraction derived from malignant effusion was significantly different from that of other fractions obtained both from malignant and nonmalignant fluids.