vasoactive-intestinal-peptide and Stomach-Neoplasms

A case of mixed (composite) glandular-endocrine cell carcinoma of the stomach is presented. Whereas the admixture of rare endocrine cells in ordinary adenocarcinoma of the stomach is a rather frequent occurrence, gastric tumors with an approximately equal proportion of glandular and endocrine cells are rare, and only 20 well-documented cases have been reported. Our case is unique in its range of histopathologic patterns, including well-differentiated and poorly differentiated adenoendocrine carcinoma as well as amphicrine differentiation. Immunohistochemical and electron microscopic findings are documented and the clinical characteristics of all reported cases tabulated. From the limited experience of these 21 cases, glandular-endocrine carcinoma of the stomach is found to have the following clinicopathologic features: It affects adults aged 32 to 74 years, (mean, 52.5 years) and has a male:female ratio of 1.3:1. It is located with almost equal frequency in the gastric body and antrum and has a poor prognosis, similar to that of advanced ordinary gastric carcinoma.

Topics: Adult; Aged; Carcinoid Tumor; Carcinoma; Chorionic Gonadotropin; Chromogranins; Female; Humans; Immunohistochemistry; Male; Microscopy, Electron; Middle Aged; Stomach Neoplasms; Vasoactive Intestinal Peptide

Three separate sets of receptors sensitive to VIP, GIP and pancreatic/entero-glucagons, have been characterized in HGT-1 cells. The order of relative potencies of VIP receptor agonists was VIP greater than rh GRF-43, rh GRF-29 greater than PHI greater than hp GRF-40, secretin. G-37 was about 4 times less potent than G-29 in HGT-1 cells (G-29 greater than G-37), whereas it was about 20 times more potent than G-29 in rat fundic glands (G-37 greater than G-29). Adenylate cyclase in HGT-1 cells was stimulated by VIP, G-29, G-37 and GIP, over a concentration from 3.16 X 10(-9) to 3.16 X 10(-7) M GIP. The experimental data: (1) support the enterogastrone activity of GIP, via adenylate cyclase activation and somatostatin release by gastric D cells; (2) demonstrate that HGT-1 cells originating from a human fundic tumor are sensitive to the glucagon-like peptides G-29 and -37, as rat fundic glands; (3) indicate that the pharmacological properties of the VIP receptor in this human gastric cell line are similar to those characterized in normal human gastric glands.

Topics: Adenylyl Cyclases; Cell Line; Cyclic AMP; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptides; Humans; Receptors, Cell Surface; Receptors, Gastrointestinal Hormone; Receptors, Glucagon; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Vasoactive Intestinal Peptide

Topics: Bombesin; Cholecystokinin; Cimetidine; Epidermal Growth Factor; Gastric Inhibitory Polypeptide; Gastrins; Gastrointestinal Hormones; Humans; Motilin; Nerve Tissue; Pancreas; Pancreatic Polypeptide; Pituitary Gland; Secretin; Somatostatin; Stomach Neoplasms; Vasoactive Intestinal Peptide; Zollinger-Ellison Syndrome

Topics: Adenoma, Islet Cell; Cholecystokinin; Gastric Juice; Gastrins; Gastrointestinal Hormones; Glucagon; Humans; Neoplasms; Pancreatic Neoplasms; Paraneoplastic Endocrine Syndromes; Peptides; Precancerous Conditions; Secretin; Somatostatin; Stomach Neoplasms; Vasoactive Intestinal Peptide; Zollinger-Ellison Syndrome

Intestinal adenocarcinomas and various endocrine tumors express large numbers of high-affinity receptors for vasoactive intestinal peptide (VIP). We have evaluated the usefulness of scanning with VIP labeled with iodine-123 for tumor localization in patients with gastrointestinal tumors.. Radioiodinated VIP was purified by high-pressure liquid chromatography and administered as a single intravenous bolus injection (300 pmol [1 microgram]). Scanning with radiolabeled VIP was compared with computed tomography and scanning with somatostatin analogues in 79 patients with colorectal cancer, pancreatic carcinoma, gastric cancer, carcinoid tumor, or insulinoma.. Visualization of gastrointestinal tumors and metastases was obtained with radiolabeled VIP. Binding of the labeled peptide by primary tumors and metastases was visible shortly after the injection and was still demonstrable at 24 hours. In patients with colorectal adenocarcinomas, primary or recurrent tumors were visualized in 10 of 10, liver metastases in 15 of 18, lung metastases in 2 of 3, and lymph-node metastases in 4 of 4. Primary pancreatic adenocarcinomas were visualized by imaging in 10 of 12 patients, and liver metastases were seen in 7 of 7. Primary or recurrent gastric adenocarcinomas were visualized in 5 of 5 patients, and liver metastases were seen in 2 of 2 patients. VIP scans were positive in 9 of 10 patients with carcinoid tumors and in 4 of 4 patients with insulinomas. Some tumors with positive VIP scans were also visualized with somatostatin analogues (4 of 17 colorectal adenocarcinomas, 8 of 9 carcinoids, and 2 of 2 insulinomas). In vitro binding studies confirmed the presence of VIP receptors on gastrointestinal tumors.. Scanning with radiolabeled VIP can visualize intestinal tumors and metastases that express receptors for VIP.

Topics: Adenocarcinoma; Carcinoid Tumor; Colorectal Neoplasms; Female; Gastrointestinal Neoplasms; Humans; Insulinoma; Iodine Radioisotopes; Male; Octreotide; Pancreatic Neoplasms; Radionuclide Imaging; Receptors, Somatostatin; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Vasoactive Intestinal Peptide

Physiological roles of enterohormones such as secretion, absorption and digestion were supported by clinical data. Overexpression of cholecystokinin (CCK), neurotensin (NT) and vasoactive intestinal peptide (VIP) receptors occur in gastrointestinal (GI) malignancies. The aim of the paper was to compare plasma levels of CCK, peptide YY (PYY), VIP and NT in patients with gastrointestinal malignancies and healthy controls. The study included 80 patients (37 men and 43 women) with GI malignancies (20 with gastric and 60 with colorectal cancers). Median age of the patients was 62.9 years (range: 40-85 years). Control group was comprised of 30 healthy persons with median age 59.8 years (range: 40-82 years). Fasting plasma concentrations of CKK, PYY, NT, and VIP were determined at rest, using ELISA kits for automated systems. Comparative analysis of enterohormone levels in patients with various types of gastrointestinal malignancies demonstrated presence of some cancer-specific alterations. Patients with gastric cancers presented with lower plasma concentrations of CCK than healthy controls and individuals from colorectal cancers (p = 0.02). The highest plasma concentrations of neurotensin was found in colorectal cancer patients in comparison to gastric (p = 0.02). The plasma levels of VIP observed in gastric cancer group were lower than in colorectal cancer patients (p = 0.01). Patients with GI malignancies may present with tumor-specific alterations in plasma enterohormone levels.

Topics: Adult; Aged; Aged, 80 and over; Cholecystokinin; Colorectal Neoplasms; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Neurotensin; Peptide YY; Stomach; Stomach Neoplasms; Vasoactive Intestinal Peptide

Gastro-entero-pancreatic neuroendocrine tumors (GEPNETs) are increasing in incidence, and accurate staging is important for selecting the appropriate treatment. (68)Ga-DOTATATE imaging is a promising approach for detecting GEPNETs and could help in selecting optimal therapeutic strategies. The aim of this study was to prospectively determine the clinical utility of (68)Ga-DOTATATE positron emission tomography (PET)/computed tomography (CT) in detecting unknown primary and metastatic GEPNETs.. One hundred thirty-one patients were enrolled in a prospective study of patients undergoing (68)Ga-DOTATATE PET/CT, (111)In-pentetreotide single-photon emission computed tomography (SPECT)/CT and multiphasic CT scan, and/or magnetic resonance imaging in a blinded fashion with comprehensive biochemical testing. The primary outcome measure was the detection of lesions by each imaging study.. (68)Ga-DOTATATE PET/CT imaging detected 95.1% of lesions (95% CI, 92.4% to 96.8%) with an average maximum standardized uptake value of 65.4 ± 47 (range, 6.9 to 244), anatomic imaging detected 45.3% of lesions (95% CI, 37.9% to 52.9%), and (111)In-pentetreotide SPECT/CT detected 30.9% of lesions (95% CI, 25.0% to 37.5%), with a significant difference between imaging modalities (P < .001). In four of 14 patients (28.6%), (68)Ga-DOTATATE PET/CT found a previously unknown primary tumor, and detected primary GEPNET, lymph node, and distant metastases correctly in 72 of 113 lesions (63.7%) when compared with histopathology, with 22.1% and 38.9% detected by using (111)In-pentetreotide SPECT/CT and anatomic imaging, respectively. On the basis of findings with (68)Ga-DOTATATE PET/CT, 43 of 131 patients (32.8%) had a change in management recommendation. In patients with carcinoid symptoms but negative biochemical testing, (68)Ga-DOTATATE PET/CT detected lesions in 65.2% of patients, 40% of which were detected neither by anatomic imaging nor by (111)In-pentetreotide SPECT/CT.. (68)Ga-DOTATATE PET/CT imaging provides important information for accurate staging of GEPNETs and selection of appropriate treatment interventions even in the absence of biochemical evidence of disease in symptomatic patients.

Topics: Adult; Aged; Aged, 80 and over; Chromogranin A; Female; Humans; Hydroxyindoleacetic Acid; Intestinal Neoplasms; Liver Neoplasms; Lymphatic Metastasis; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neoplasms, Unknown Primary; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Pancreatic Polypeptide; Phosphopyruvate Hydratase; Positron-Emission Tomography; Prospective Studies; Somatostatin; Stomach Neoplasms; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Vasoactive Intestinal Peptide; Young Adult

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of cells, which have been revealed to inhibit T-cell responses in tumor-bearing mice. In addition, a number of immune suppressive mechanisms have linked MDSCs and the development of human cancer. However, the role of MDSCs in human gastric cancer tissue remains to be elucidated as specific markers are lacking. Therefore, the aim of the present study was to investigate the frequency and immune suppressive function of MDSCs denoted in the present study as cluster of differentiation 14 (CD14)+human leukocyte antigen (HLA)-DR-/low in gastric cancer patients. In the present study, MDSCs were directly isolated and characterized from the tumor and adjacent normal tissue of gastric cancer patients. Functional analysis of the CD14+HLA-DR-/low MDSCs co-cultured with allogeneic CD4+ T cells were performed and compared with controls. In addition, the interferon-γ (IFN-γ) and interleukin (IL)-2 production was compared in order to investigate the capacity of vasoactive intestinal peptide (VIP) to induce CD14+HLA-DR(-/low) MDSC-mediated CD4+ T-cell dysfunction and whether IL-10 secretion is involved in this mechanism. As a result, the quantity of CD14+HLA-DR(-/low) cells in tumor tissue from gastric cancer patients was significantly higher than that in the adjacent normal tissue. In addition, CD14+HLA-DR-/low MDSCs isolated from tumor tissue were observed to inhibit the CD4+ T-cells' immune responses in comparison with those from the adjacent normal tissue. Furthermore, VIP was able to induce the differentiation of CD14+ mononuclear cells isolated from healthy donor peripheral blood mononuclear cells into activated MDSC cells. Of note, the immunosuppressive effect of VIP-induced CD14+HLA-DR(-/low) MDSCs on CD4+ T cells was mediated by IL-10 secretion, which was demonstrated in the subsequent decrease of IFN-γ and IL-2 production. In conclusion, CD14+HLA-DR(-/low) cells were significantly increased in gastric cancer tissue and were shown to have a critical role in CD4+T-cell immunosuppression. In addition, VIP as a novel cytokine may induce the differentiation of CD14+ mononuclear cells towards CD14+HLA-DR(-/low) MDSCs. An improved understanding of phenotypic heterogeneity and the mechanism of generation of MDSCs in gastric cancer patients is important in the design of effective immunotherapeutic strategies.

Topics: Animals; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Differentiation; Cell Proliferation; HLA-DR Antigens; Humans; Immunosuppression Therapy; Interferon-gamma; Interleukin-10; Interleukin-2; Leukocytes, Mononuclear; Lipopolysaccharide Receptors; Mice; Myeloid Cells; Stomach Neoplasms; Vasoactive Intestinal Peptide

Vasoactive intestinal peptide (VIP) has been regarded as deactivator for macrophages. However, the depressive effect of VIP on tumor-associated macrophages (TAM) has not been recognized. In the present study, we investigated the effect of VIP on gastric cancer via TAM by suppressing expression levels of TNFα, IL-6, IL-12 and iNOS. Real-time PCR was carried out to examine the expression of CD68 to determine the levels of TAM. The effect of VIP on cell activities was assayed by proliferation assay, colony formation and flow cytometry analysis. The co-culture of TAM and human gastric cancer cell line MKN-45 were performed to understand whether the VIP affects the gastric cancer cells via TAM. Further, the tumor formation in a nude mouse model and VIP injection were performed to illustrate the effect on tumor progression in vivo. CD68 was high expressed in gastric cancer indicating high level of TAM in gastric cancer. Treatment with VIP significantly depressed TAM activation. Moreover, the expression of TNFα, IL-6, IL-12 and iNOS in TAM were depressed by VIP treatment, and the VIP treated TAM depressed gastric cancer cells. The experiment in the nude mouse model also suggested that by injection with TAM+VIP, the tumor volume and tumor weight were both decreased significantly. These data suggest that treatment with VIP inhibits gastric cancer.

Topics: Adult; Animals; Blotting, Western; Cell Line, Tumor; Coculture Techniques; Down-Regulation; Female; Flow Cytometry; Heterografts; Humans; Immunohistochemistry; Interleukin-12; Interleukin-6; Macrophage Activation; Macrophages; Male; Mice; Mice, Nude; Middle Aged; Nitric Oxide Synthase Type II; Real-Time Polymerase Chain Reaction; Stomach Neoplasms; Tumor Microenvironment; Tumor Necrosis Factor-alpha; Vasoactive Intestinal Peptide

To investigate the expression of vasoactive intestinal peptide (VIP) in gastric adenocarcinoma, and to evaluate the correlation of VIP level with clinical pathologic parameters.. The level of VIP in sera from gastric adenocarcinoma patients and healthy people was investigated by ELISA. Moreover, the differential gene expression between gastric adenocarcinoma, gastric dysplasia, and the corresponding normal gastric mucosa were determined by RT-PCR. Western Blot was also used to measure the expression of VIP in the gastric adenocarcinoma and the normal gastric mucosa.. The serum level of VIP was (5.794 +/- 0.014) ng/ ml in normal control and was (14.437 +/- 0.825) ng/ml in gastric adenocarcinoma patients, showing significant difference (P < 0.05). Meanwhile,the V/B of gastric adenocarcinoma tissues was greater than that of gastric dysplasia and the corresponding normal gastric mucosa (P <0.01), the values of V/B were 1.5261 +/- 0.3028, 0.9334 +/- 0.2872,and 0.9051 +/- 0.2794, respectively. The values of V/B between normal gastric mucosa and gastric dysplasia were not different significantly (P > 0.05). There were significantly negative correlation between the VIP mRNA expression of the differentiation degree of tumor (P < 0.05). The VIP mRNA expression was higher in gastric adenocarcinoma with lymph node metastasis than that without lymph node matastsis (P < 0.05). The VIP protein expression of the gastric adenocarcinoma tissues was greater than that of normal control.. This findings provide a direct evidence to support the possibility that VIP play a cofactor role in the pathogenesis of gastric adenocarcinoma.

Topics: Adenocarcinoma; Gastric Mucosa; Gene Expression; Humans; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stomach Neoplasms; Vasoactive Intestinal Peptide

Vasoactive intestinal peptide (VIP) is a gastrointestinal hormone in the secretin-VIP family. It has been reported that VIP affects some tumor growth, and there is a VIP autocrine regulation in some cancers. However, the effect of VIP on gastric adenocarcinoma is not clear yet. The aim of the present study was to investigate the effect of VIP on gastric adenocarcinoma, especially autocrine regulation of VIP on gastric adenocarcinoma.. VIP mRNA and protein, and its receptor mRNA (VIPR(1) and VIPR(2)) were measured in 15 normal antrum mucosa, 20 gastric adenocarcinoma tissues, and the SGC7901 gastric adenocarcinoma cell line by using reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry, or radioimmunoassay methods. The effect of the VIP protein and its antagonist (D-p-Cl-Phe6, Leu17)-VIP on SGC7901 cell growth was detected by methylthiazolyldiphenyl-tetrazolium bromide (MTT) method. The expressions of c-myc mRNA and ornithine decarboxylase (ODC) mRNA in SGC7901 cells before and after the incubated VIP protein and/or its antagonist were also measured by RT-PCR method.. The VIP mRNA expression in gastric adenocarcinoma tissues was significantly higher than that in normal antrum mucosa (P < 0.01). The VIP-positive immunoreactivity cells existed in 40% of gastric adenocarcinoma tissues, but not in normal tissues (P < 0.01). The VIP-positive immunoreactivity nerve fibers were observed in normal tissues, but not in adenocarcinoma tissues (P < 0.01). The expression rate of VIPR(1) mRNA in adenocarcinoma tissues was significantly lower than that in normal tissues, but that of VIPR(2) mRNA in the two kinds of tissues were similar (P > 0.05). In addition, the expression quantity of VIPR(1) mRNA and VIPR(2) mRNA in adenocarcinoma tissues was significantly lower than that in normal tissues (P < 0.05). SGC7901 cells expressed not only VIP mRNA and the VIP protein, but also VIPR(1) and VIPR(2) mRNA. 10(6) SGC7901 cells secreted 13.15 +/- 8.54 pg VIP on average. VIP did not affect the proliferation of SGC7901 cells, but the antagonist stimulated the proliferation of SGC7901 cells from 10(-5) to 10(-8) mol/L concentration incubated for 24-96 h. VIP downregulated the expressions of c-myc and ODC mRNA, but its antagonist upregulated their expressions.. The expression of VIP mRNA upregulates, but the expressions of VIPR mRNA downregulates in gastric adenocarcinoma tissues. The gastric adenocarcinoma tissues contain endocrine cells to secrete VIP, which show malignant specialities. The VIP autocrine regulation exists in SGC7901 cells, and potentially inhibits the proliferation of the cells by downregulating the expressions of c-myc and ODC mRNA. It suggests that VIP may play an important role in the regulation of the growth of gastric cancer cells.

Topics: Adenocarcinoma; Adolescent; Adult; Cell Line, Tumor; Cell Proliferation; Female; Humans; Immunohistochemistry; Male; Middle Aged; Ornithine Decarboxylase; Proto-Oncogene Proteins c-myb; Receptors, Vasoactive Intestinal Polypeptide, Type I; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stomach Neoplasms; Vasoactive Intestinal Peptide

To explore the relationship between precancerous lesions of gastric antrum and substance P (SP) , vasoactive intestinal peptide ( VIP) , calcitonin gene-related peptide (CGRP), and the therapeutic mechanism of Zu' ai Weitai Granule (ZWG) , a TCM preparation.. The rat model of precancerous lesions of gastric carcinoma was induced by the combined method of N-methyl N' -nitrosoguani-dine (MNNG) and mechanical injury on gastric mucosa. The pathologic morphological changes of gastric mucosa were observed after prophylactic and therapeutic administration of ZWG. In the meantime,the changes in SP, VIP and CGRP contents were determined by immunohistochemical staining.. The contents of SP and CGRP in gastric antrum were obviously improved in the ZWG group when compared with those in the control group (P <0. 05). There was no significant difference in VIP content between the two groups (P >0. 05).. ZWG could improve SP, VIP, and CGRP contents in rats' gastric antrum either as prophylactic administration or therapeutic administration.

Topics: Animals; Antineoplastic Agents, Phytogenic; Calcitonin Gene-Related Peptide; Carcinoma; Drugs, Chinese Herbal; Precancerous Conditions; Pyloric Antrum; Rats; Stomach Neoplasms; Substance P; Vasoactive Intestinal Peptide

To develop a tumor imaging agent for vasoactive intestinal peptide (VPAC) receptor and evaluate its biological activity and pharmacokinetics of radiolabeled peptide.. VIP(28) was modified at the carboxyl terminal by the addition of His-tag which was the chelating site of (99m)Tc(I) and the general purification tag for immobilized metal ion affinity chromatography. Biological activity of the modified VIP(28) analogue MY34 was examined in vitro by radiological cell-binding assay, rabbit internal anal sphincter (IAS) smooth muscle relaxing assay and immunocytochemical stain. The pharmacokinetics of this labeled peptide was examined in C57 mice.. MY34 could relax the IAS smooth muscle and bind VPAC receptors on tumor cell membranes. (99m)Tc- MY34, with a yield of about 90%, was stable enough for practical use. Both MY34 and VIP(28) could inhibit the binding between the labeled peptide and VPAC receptor. The pharmacokinetics of [(99m)Tc(H(2)O)(3)(CO)(3)]-MY34 was studied in mice conformed well with the two-compartment model (Wi = 1/C(2)), with a t(1)/(2alpha) of 16.35 min and a t(1)/(2beta) of 1013.56 min.. MY34 possesses physiological activities and specific receptor binding characteristics similar to those of natural VIP(28).

Topics: 3T3 Cells; Animals; Binding, Competitive; Isotope Labeling; Mice; Mice, Inbred C57BL; Muscle, Smooth; Organotechnetium Compounds; Peptides; Rabbits; Radionuclide Imaging; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Tumor Cells, Cultured; Vasoactive Intestinal Peptide

Stomach and small bowel both influence gastrointestinal motility. We studied which portion of the stomach was essential for the regulation of gastrointestinal movement and determined the role of vasoactive intestinal polypeptide in this regulation. The study subjects consisted of 45 controls, 46 patients after subtotal gastrectomy, and 13 patients after total gastrectomy for stomach cancer. Orocecal transit time was measured, using the hydrogen breath test, to represent gastrointestinal movement, while plasma vasoactive intestinal polypeptide level was simultaneously assessed. The orocecal transit times in the study groups were (means +/- SD) 91.1 +/- 45.0, 57.1 +/- 34.3, and 60.8 +/- 34.8 min, respectively (P < 0.01). In the subtotal gastrectomy patients, age showed a negative correlation with orocecal transit time (r = -0.388; P < 0.01). In the total gastrectomy patients, no particular demographic factor influenced orocecal transit. Plasma vasoactive intestinal polypeptide levels in the three groups were 20.7 +/- 10.8, 22.7 +/- 10.9, and 20.6 +/- 9.1 pg/ml, respectively (NS). We conclude that both types of gastrectomies enhanced gastrointestinal movement, showing a similar effect, and that the distal stomach plus pylorus are most likely to exert an important inhibitory mechanism in the regulation of this movement. Vasoactive intestinal polypeptide is not a major peptide mediating this regulation.

Topics: Aged; Breath Tests; Case-Control Studies; Duodenal Ulcer; Female; Gastrectomy; Gastrointestinal Transit; Humans; Hydrogen; Male; Pylorus; Stomach; Stomach Neoplasms; Vasoactive Intestinal Peptide

The purpose of this study was to investigate the peculiarities of hormonal regulation of adenylate cyclase (AC) of blood lymphocytes in colorectal cancer patients and to compare these peculiarities with hormone sensitivity of AC of colorectal tumors and normal colonic mucosa. Basal and stimulated lymphocyte AC activity was studied in 51 healthy persons and 52 cancer patients (14 with colon cancer, 21 with rectal cancer and 17 with stomach cancer) aged 20-75 years. In 31 of 35 patients with colorectal cancer the AC activity was studied simultaneously in lymphocytes, tumor tissue and normal colonic mucosa. To evaluate basal and stimulated AC activity the measurement of c-AMP (Amersham kits) formed in the presence of ATP regenerating system was used. Basal and by VIP, pentagastrin and sodium fluoride stimulated AC activity in lymphocytes of gastrointestinal cancer patients was lower than in lymphocytes of healthy subjects of similar age. Stage dependence of the parameters under study was not found. There was a tendency for higher basal and stimulated lymphocyte AC activity in colon cancer patients as compared to stomach and rectal cancer patients. In colorectal cancer patients the peculiarities of lymphocyte AC reactions to stimulation were closer to those in tumor tissue but not to those in normal colonic mucosa. The reaction of lymphocyte AC to VIP and glucagon coincided more frequently with tumor AC reactions to the same hormones in case of hormone nonsensitive tumors. Thus, basal and stimulated lymphocyte AC activity in colorectal cancer patients was modified to some degree by tumor factors. Lymphocyte AC reactions to VIP and glucagon may be considered as indirect markers of hormone sensitivity of colonic tumors. Moreover, the probability of discovery of hormone nonsensitive tumors by this way is more reliable than hormone sensitive ones.

Topics: Adenosine Triphosphate; Adenylyl Cyclases; Adult; Aged; Calcitonin; Colonic Neoplasms; Epinephrine; Glucagon; Humans; Intestinal Mucosa; Lymphocytes; Middle Aged; Pentagastrin; Rectal Neoplasms; Sodium Fluoride; Stomach Neoplasms; Vasoactive Intestinal Peptide

This investigation, conducted on 35 patients with advanced-stage gastric cancer, included 28 men and 7 women with a mean age of 50.1 years; also studied were 33 normal subjects as controls: 26 men and 7 women with a mean age of 45.8 years. Samples of blood and gastric juice were collected at fasting and in gastroscopy respectively. Substance P (SP), beta-endorphin (beta-EP), vasoactive intestinal peptide (VIP), motilin (MTL), gastrin (GT), and leu-enkephalin (LEK) of the sera and gastric juices were measured by radioimmunoassay kits. In the patients, SP and beta-EP of serum and gastric juice, and VIP, MTL and LEK of gastric juice, were higher than in the normal subjects (p < 0.01); gastrin of serum and gastric juice were decreased (p < 0.01). Serum and gastric juice SP, beta-EP levels correlated negatively with the gastrin (r = 0.462-0.519, p < 0.05). These data support the assumption that study of the peptides of serum and gastric juice can show a clinically significant change in gastric cancer patients.

Topics: Adult; Aged; Endorphins; Female; Gastric Juice; Humans; Male; Middle Aged; Motilin; Neuropeptides; Stomach Neoplasms; Substance P; Vasoactive Intestinal Peptide

Hypercalcitoninemia in gastroenteropancreatic tumors associated with calcitonin immunoreactivity is rare.. We report here two patients in whom pancreatic neuroendocrine tumors both contained and secreted immunoreactive calcitonin. Both patients experienced elevated basal calcitonin immunoreactivity.. The peak responses of immunoreactive calcitonin occurred 5 minutes after pentagastrin administration in these two patients and were 30% and 180% above basal concentrations corresponding to peak increments of 0.39 and 8.78 ng/ml, respectively. The immunoreactive calcitonin response to pentagastrin in these two patients was not significantly different from that seen among five patients with medullary carcinoma of the thyroid gland.. It does not appear that immunoreactive calcitonin responses to pentagastrin stimulation will discriminate between patients with medullary carcinoma of the thyroid gland and those with nonfamilial, gastroenteropancreatic neuroendocrine tumors that express calcitonin immunoreactivity. In patients with secretory diarrhea and/or flushing, an elevated level of immunoreactive calcitonin, in the absence of a thyroid mass in the neck, may herald the presence of a gastroenteropancreatic neuroendocrine tumor.

Topics: Adenoma, Islet Cell; Aged; Calcitonin; Female; Humans; Liver Neoplasms; Middle Aged; Multiple Endocrine Neoplasia; Pancreatic Neoplasms; Pancreatic Polypeptide; Pentagastrin; Stomach Neoplasms; Thyroid Neoplasms; Vasoactive Intestinal Peptide

The effects of vaso-active intestinal peptide (VIP) on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats given VIP every other day for 27 weeks after oral administration of MNNG for 25 weeks. In week 52, administration of VIP caused a significant increase in the incidence of gastric cancers, but did not influence their histological appearance. VIP significantly increased the labeling indices of the antral mucosa. Our findings indicate that VIP enhances gastric carcinogenesis, and that this effect may be related to its effect in increasing cell proliferation of the antral epithelial cells.

Topics: Animals; Drug Synergism; Gastric Juice; Gastrins; Hyperplasia; Male; Methylnitronitrosoguanidine; Rats; Rats, Inbred Strains; Stomach; Stomach Neoplasms; Vasoactive Intestinal Peptide

Vasoactive intestinal polypeptide (VIP) is a gut neuroendocrine polypeptide that increases cyclic adenosine monophosphate (cAMP) production in cells with VIP receptors. Some gastrointestinal cancer cells possess functional receptors for VIP; however, the role of VIP in regulation of growth of gastric cancer cells has not been determined. The purpose of this study was to determine whether VIP and other agents that increase cAMP regulate growth of a human gastric cancer cell line (AGS) and whether these agents regulate expression of c-myc proto-oncogene, which is required for cell proliferation. We measured levels of cAMP by radioimmunoassay, and we used Northern blot analysis to examine c-myc messenger RNA expression. Cell-growth studies were carried out in media supplemented with 3% serum, and cells were counted with a Coulter counter. We found that VIP significantly increased cAMP production of AGS cells in a dose-dependent manner, whereas secretin, glucagon, and peptide histidine methionine (PHM) did not stimulate cAMP production. Exogenous cAMP (8-bromo-cAMP) inhibited AGS cell growth in a dose-dependent manner. VIP acted synergistically with either isobutylmethyl-xanthine or forskolin to inhibit AGS cell proliferation. The increased c-myc expression, which was induced by serum, was inhibited by simultaneous treatment with VIP and isobutylmethyl-xanthine. We have found that AGS cells have specific, functional VIP receptors (activation of which are negatively correlated with cell growth) and that the mechanism by which VIP acts to inhibit cell growth appears to be due, in part, to cAMP-dependent regulation of c-myc proto-oncogene expression.

Topics: 1-Methyl-3-isobutylxanthine; 8-Bromo Cyclic Adenosine Monophosphate; Blotting, Northern; Cell Division; Colforsin; Cyclic AMP; Drug Synergism; Gene Expression Regulation, Neoplastic; Genes, myc; Humans; Proto-Oncogene Mas; RNA, Messenger; Stomach Neoplasms; Tumor Cells, Cultured; Vasoactive Intestinal Peptide

The Mastomys (Praomys natalensis) species are a unique natural model in which the bioactivity of gastric carcinoids may be studied. Several investigators have previously demonstrated that these tumors contain large amounts of histamine. In this study we investigated the presence of peptides associated with the neoplasm. The levels and location of gastrin, gastric inhibitory peptide (GIP), neurotensin, peptide YY (PYY), pancreatic polypeptide (PP), glucagon, bombesin, vasoactive intestinal peptide (VIP) and somatostatin (SRIF) were investigated by radioimmunoassay and immunocytochemistry. In addition the distribution of these peptides were evaluated in the gastrointestinal tract of young and old animals to investigate possible age-related changes. PYY and enteroglucagon (EG) were significantly (P less than 0.001) elevated in both tumor tissue (676 +/- 152, 551 +/- 164 pmol/g) and plasma (620 +/- 160, 500 +/- 147 pmol/l) of tumor-bearing animals. Immunocytochemistry revealed PYY- and EG-like immunoreactivity in 20-30% of tumor cells. A significant decrease (P less than 0.05) in bombesin was noted in older animals, but no changes in gastric tissue content of PYY or EG could be detected between young and old animals. Gastrin was not detected in tumors and there were no significant changes in tissue or plasma levels with age. Small bowel concentrations of VIP and PYY were higher in the older mastomys (P less than 0.05). In contrast, colonic levels of bombesin, VIP, somatostatin and PYY were significantly lower (P less than 0.05) in older mastomys compared with young. The age-related changes in several peptides may reflect an adaptive response to acid hypersecretion. The multi-hormonal character of these neoplasms suggests that these tumors develop from a pluripotential stem cell.

Topics: Age Factors; Animals; Bombesin; Carcinoid Tumor; Gastric Inhibitory Polypeptide; Gastrins; Immunohistochemistry; Muridae; Neoplasm Proteins; Neurotensin; Pancreatic Polypeptide; Peptide YY; Peptides; Radioimmunoassay; Stomach Neoplasms; Vasoactive Intestinal Peptide

We present a case of secondary achalasia due to an adenocarcinoma of the stomach with no tumor infiltration of the esophagus. Immunohistochemical staining revealed a massive infiltration of activated eosinophils in the muscularis of the esophagus with secretion of the highly cytotoxic and neurotoxic eosinophil cationic protein (ECP). Immunohistochemical staining for the neuropeptides VIP and substance P, as well as the histochemical demonstration of AChE, revealed a nearly total absence of all three neurotransmitters/modulators compared to control. The hypothesis is advanced that eosinophil neurotoxicity is the cause of secondary achalasia.

Topics: Adenocarcinoma; Aged; Blood Proteins; Eosinophil Granule Proteins; Esophageal Achalasia; Esophagus; Humans; Immunohistochemistry; Male; Nerve Fibers; Ribonucleases; Stomach Neoplasms; Substance P; Vasoactive Intestinal Peptide

In human antral membranes, VIP and its natural analogs inhibited the binding of HPLC-purified 125I-VIP, according to the following order of potency: VIP greater than rh GRF greater than helodermin greater than r PHI greater than PHM greater than p PHI greater than hp GRF greater than h, p secretin. No specific binding was detected in plasma membranes purified from the human fundus. In human antral membranes, Scatchard plots were compatible with the existence of two classes of VIP receptors, the first class with high affinity and low binding capacity (Kd = 0.1 nM, Bmax = 10 fmol/mg protein) and another class with a low affinity and higher binding capacity (Kd = 12) nM, Bmax = 1,000 fmol/mg protein). The structure of the VIP receptor in purified plasma membranes prepared from human antral glands and from the HGT-1 human gastric cancer cells was subsequently probed using the cross-linking reagent DSP and 125I-VIP. In agreement with the pharmacological study and the Scatchard analysis of the binding data, SDS gel electrophoresis of the solubilized receptor identified two radiolabeled peptides Mr 67,000 and 34,000 containing disulfide bonds. According to its sensitivity to low doses of VIP and to GTP, the Mr 67,000 binding site represents the membrane domains involved in the physiologial regulation of adenylate cyclase by VIP in normal and transformed human gastric epithelia.

Topics: Binding, Competitive; Cell Membrane; Gastrectomy; Gastric Mucosa; Humans; Kinetics; Pyloric Antrum; Receptors, Gastrointestinal Hormone; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Stomach Ulcer; Vasoactive Intestinal Peptide

Imidazole and isocytosine-furan derivatives inhibited H2 receptor activity in HGT-1 cells, in accordance with the following relative potencies (IC50 = 2.3 microM cimetidine as reference): SKF 93479 = cimetidine = 100 greater than metiamide = 62 greater than SKF 92408 = 2 greater than SKF 91581 = 0.07). The Schild plot for cimetidine was linear (slope = 0.97) with a pA2 value of 6.72 +/- 0.12 (Ki = 0.18 microM cimetidine), suggesting competitive inhibition. Preincubation of HGT-1 cells for 10 min with H2 antagonists at 2 microM concentration resulted in 90-100% inactivation (SKF 93479 and oxmetidine) and 65% inactivation (ranitidine) which persisted for 30 min, even after a washout period. Accordingly, the kinetics of 2 microM [3H] SKF 93479 binding to HGT-1 cells revealed a half-time for association of 10 min and a dissociation half-time of 120 min. There was a good correlation between the kinetics and relative potencies of cimetidine and SKF 93479 in inhibiting H2 receptor activity in purified plasma membranes (40 nM) as well as in intact HGT-1 cells preincubated for 2 hr with SKF 93479 before histamine addition (45 nM). Chronic treatment of HGT-1 cells for 6 days with 2 microM SKF 93479 specifically blocked H2 receptor activity since cyclic AMP generation induced by other hormones and agents such as VIP, glucagon, GIP and sodium fluoride was unaltered. In contrast, short term and chronic treatment by cimetidine was readily reversible. The isocytosine-furan derivative SKF 93479 differs from the imidazole analogue cimetidine by its apparent irreversible action, due to the slow onset of association from HGT-1 cells. The isocytosine ring in SKF 93479 and oxmetidine seems to play a preponderant role in their apparent long-lasting, irreversible actions.

Topics: Cell Line; Cimetidine; Cyclic AMP; Histamine; Histamine H2 Antagonists; Humans; Kinetics; Pyrimidinones; Receptors, Cell Surface; Receptors, Histamine; Receptors, Histamine H2; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Structure-Activity Relationship; Vasoactive Intestinal Peptide

Homologous loss of histamine H2-receptor activity (cAMP generation) was observed after short-term (10-20 min) or chronic treatment (6 days) of cultured HGT-1 cells with histamine (desensitization) or the H2-receptor antagonist SKF 93479. This inactivation process was not observed when HGT-1 cells were exposed to the classical H2-antihistamine cimetidine. The data show: (1) that the compound SKF 93479 has a very prolonged inhibitory action on histamine receptor activity, suggesting an irreversible interaction between the antagonist and the receptor; (2) that cimetidine is a reversible H2-receptor antagonist which can be removed without changing the the efficacy and the potency of histamine on gastric cells; (3) that the H2-receptor antagonists cimetidine and SKF 93479 specifically block histamine H2-receptor activity in HGT-1 cells since cAMP generation induced by other hormones such as vasoactive intestinal peptide (VIP), glucagon or gastric inhibitory peptide (GIP) was unchanged after treatment; (4) the first evidence for time-dependent (half-life: 20 min) desensitization of gastric H2-receptors.

Topics: Cell Line; Cimetidine; Histamine; Histamine H2 Antagonists; Humans; Pyrimidinones; Receptors, Histamine; Receptors, Histamine H2; Stomach Neoplasms; Vasoactive Intestinal Peptide

A total of 87 surgical cases of gastric carcinoma including 3 carcinoid tumors were investigated with the methods of silver reaction and immunoperoxidase stain for 8 different brain-gut hormones. Argyrophil (AP) cells were demonstrated in 38 cases (44%), argentaffin (AF) cells in 18 (21%) and endocrine cells in 13 (14%). The occurrence of endocrine cells had no relation with histological types. Glicentin cells were demonstrated in 10 cases, somatostatin in 7, motilin in 3, beta-endorphin in 2 and gastrin in one. Endocrine cells appeared generally in small numbers except one carcinoid tumor which had numerous somatostatin cells. No single cell positive for more than two kinds of hormones could be demonstrated. Two undifferentiated carcinomas looking like carcinoid tumors had argyrophil cells and endocrine cells of either somatostatin or beta-endorphin. These results suggest that carcinoid-like carcinoma or endocrine cell carcinoma may lie on the intermediate state between carcinoma and carcinoid tumor.

Topics: Adenocarcinoma; Adenocarcinoma, Mucinous; Adult; Carcinoid Tumor; Endorphins; Female; Gastrins; Gastrointestinal Hormones; Glucagon; Histocytochemistry; Humans; Male; Microscopy, Electron; Middle Aged; Motilin; Proglucagon; Protein Precursors; Somatostatin; Stomach Neoplasms; Vasoactive Intestinal Peptide; Vasopressins

GIP (EC50 = 8 X 10(-9) M, 5-fold stimulation), pancreatic glucagon (EC50 = 10(-8)M, 13-fold) and porcine or chicken VIP (EC50 = 2.5 X 10(-9) M, 10-fold) are shown to activate the cAMP generating system in HGT -1 cells. Combinations of GIP, pancreatic glucagon and VIP indicate the occurrence of 3 separate sets of recognitions sites for these 3 peptides. Accordingly, chronic treatment of cultured HGT -1 cells by VIP (10(-8) M) during 6 days resulted in homologous desensitization of VIP receptor activity. Other peptides structurally related to the secretin-glucagon family, to neurotensin, or to gastrin are either ineffective or very weak agonist (hpGRF). GIP or pancreatic glucagon are inactive on the human colonic cell line HT-29, indicating the gastric specificity of the effect of GIP and glucagon in transformed epithelial cells originating from the human gastrointestinal tract. This implies that GIP and (pancreatic-entero) glucagon peptides may regulate gastric secretions directly, under similar mechanisms that those we evidenced in the rat.

Topics: Cell Line; Cyclic AMP; Dose-Response Relationship, Drug; Drug Interactions; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Glucagon; Humans; Kinetics; Receptors, Cell Surface; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Vasoactive Intestinal Peptide

Topics: Endocrine System Diseases; Enterochromaffin Cells; Female; Gastrointestinal Neoplasms; Glucagonoma; Humans; Insulinoma; Male; Multiple Endocrine Neoplasia; Pancreatic Neoplasms; Somatostatinoma; Stomach Neoplasms; Vasoactive Intestinal Peptide; Zollinger-Ellison Syndrome

In HGT-1 cells incubated at 20 degrees C for 15 min with 1 mM 3-isobutyl-1-methylxanthine (IBMX), histamine (10(-4)M) increased basal cAMP levels from 2.12 +/- 0.14 to 22.9 +/- 2 pmol per 10(6) cells, with a potency of 6.4 X 10(-6)M. IBMX was added in order to inhibit cAMP degradation by low and high Km cAMP-phosphodiesterases (cAMP-PDE). The use of specific H1, H2 agonists or antagonists indicated that the histamine effect was due to an interaction with typical H2 -receptors that are involved in gastric acid secretion. Cyclic AMP levels were also increased (10-fold) by vasoactive intestinal peptide VIP (3 X 10(-11) - 10(-8)M). Porcine peptide having N-terminal histidine and C-terminal isoleucine amide (PHI) and secretin were respectively 80 and 3600 times less potent than VIP and did not produce additive effect when tested in combinations with VIP. This observation indicates that these two peptides, structurally related to VIP, are acting through the recognition sites for VIP. Combination of VIP and histamine results in additive stimulation on intact cells as well as on membrane-bound adenylate cyclase, suggesting the existence of two cell populations bearing respectively the two sets of receptors. Two other human cancer cell lines originating from nongastric tumors (HT-29 and HL-60) possess only VIP or histamine receptors, respectively, indicating the gastric cellular originality of the HGT-1 cells. It is concluded that HGT-1 cells possess both VIP and histamine H2 receptors with similar pharmacological properties to those characterized in normal human fundic glands (1,2). Therefore, this cell line can be a good model to study drugs used therapeutically during the treatment of patients for gastric ulcer or cancer.

Topics: 1-Methyl-3-isobutylxanthine; Adenylyl Cyclases; Cell Line; Cyclic AMP; Gastric Mucosa; Gastrointestinal Hormones; Histamine; Humans; Kinetics; Receptors, Cell Surface; Receptors, Histamine; Receptors, Histamine H2; Receptors, Vasoactive Intestinal Peptide; Stomach Neoplasms; Structure-Activity Relationship; Temperature; Vasoactive Intestinal Peptide

Topics: Acute Disease; Adolescent; Adult; Duodenal Ulcer; Female; Gastrointestinal Hormones; Hepatitis; Humans; Liver Cirrhosis, Alcoholic; Male; Pancreatitis; Stomach Neoplasms; Vasoactive Intestinal Peptide

With the advent of radioimmunoassay and immunocytochemical methods, the peptides of the gastrointestinal tract have been identified and measured. Gastrinoma and insulinoma syndromes have been wall characterized. The pancreatic cholera syndrome and some of the evidence that the major manifestations of this disease may be mediated by vasoactive intestinal peptide have been re-examined. Pancreatic polypeptide seems to be an ideal peptide for study of vagal-cholinergic mechanisms that regulate hormone release; it also appears to be a tumor marker for several types of pancreatic endocrine tumors, particularly those of pancreatic cholera. Secretin and cholecystokinin are important regulators of pancreatic exocrine secretion and have been used to test pancreatic function, but there is little evidence that they account for clinical disease. Glucagon-secreting tumors produce a clinical syndrome of diabetes mellitus and distinctive skin lesions, which can be cured by tumor resection. Hormone-secreting tumors may provide insight into normal gut physiology.

Topics: Adenoma, Islet Cell; Animals; Apudoma; Cholecystokinin; Diarrhea; Dogs; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Glucagon; Hormones; Humans; Intestines; Pancreas; Pancreatic Neoplasms; Pancreatic Polypeptide; Stomach; Stomach Neoplasms; Vasoactive Intestinal Peptide

Topics: Animals; Carcinoid Tumor; Cholecystokinin; Dogs; Enterochromaffin Cells; Gastric Inhibitory Polypeptide; Gastric Mucosa; Gastrins; Gastrointestinal Hormones; Glucagon; Glucagon-Like Peptides; Humans; Intestinal Mucosa; Intestinal Neoplasms; Pancreatic Polypeptide; Rats; Secretin; Somatostatin; Stomach Neoplasms; Vasoactive Intestinal Peptide