PubMed Health⌕ Search

Biomedical subjects

M Caplin

Publications and source records attributed to M Caplin.

At least 19 recordsLinked to original sources

TNM staging of foregut (neuro)endocrine tumors: a consensus proposal including a grading system.

The need for standards in the management of patients with endocrine tumors of the digestive system prompted the European Neuroendocrine Tumor Society (ENETS) to organize a first Consensus Conference, which was held in Frascati (Rome) and was based on the recently published ENETS guidelines on the diagnosis and treatment of digestive neuroendocrine tumors (NET). Here, we report the tumor-node-metastasis proposal for foregut NETs of the stomach, duodenum, and pancreas that was designed, discussed, and consensually approved at this conference. In addition, we report the proposal for a working formulation for the grading of digestive NETs based on mitotic count and Ki-67 index. This proposal, which needs to be validated, is meant to help clinicians in the stratification, treatment, and follow-up of patients.

Biomarkers, Tumor↗

Consensus report on the use of somatostatin analogs for the management of neuroendocrine tumors of the gastroenteropancreatic system.

This consensus report gives a detailed description of the use of somatostatin analogs in the management of neuroendocrine tumors of the gastroenteropancreatic system. As background information we have outlined critical aspects of the pathology, the use of tumor markers, a definition of functional and non-functional digestive neuroendocrine tumors, different imaging modalities, surgical considerations, liver embolization and the use of cytotoxic drugs as well as interferon. Included in the report is an overview of somatostatin, somatostatin analogs and its receptor expression in different neuroendocrine tumors. It will also define the binding affinities of different somatostatin analogs to the five different subtypes of somatostatin receptor. We compare the efficacy of octreotide and lanreotide in reducing diarrhea and flushing. Side-effects are described and we provide practical information on somatostatin analog treatment.

Antineoplastic Agents, Hormonal↗

Use of stents in the palliative treatment of malignant gastric outlet and duodenal obstruction.

AIM: To evaluate the efficacy of stenting in the palliation of malignant duodenal and gastric outlet obstruction. MATERIALS AND METHODS: We retrospectively reviewed our series of patients who underwent stenting for malignant upper gastrointestinal obstruction between March 1998 and December 1999. From January 2000 data have been acquired prospectively. Our series comprises 21 stents successfully deployed in 15 patients. RESULTS: The technical and clinical success was 93% (14/15 patients). One patient required endoscopic negotiation of recurrent gastric carcinoma at the gastrojejunostomy site after failure to cross the lesion fluroscopically. Two patients required re-intervention 2 and 5 weeks after initial stent placement, for migration and ingrowth respectively. Eighteen stents were placed transorally, two stents transhepatically and one via a transgastric approach. Early complications (pain < 3 days) occurred in two patients (13%) and late complications (ingrowth, overgrowth and migration) occurred in three patients (20%). The median survival was 2.4 months (range 2-4 months). CONCLUSION: Stenting provides a less invasive palliative option than surgery with the advantage of lower morbidity and complication rates. It has the advantage of high technical and clinical success rates facilitated by alternative routes of access into the upper gastrointestinal tract via transgastric and transhepatic routes in addition to the traditional peroral route.

Adult↗

Effect of gastrin and anti-gastrin antibodies on proliferation of hepatocyte cell lines.

Gastrin (G-17) and its precursor glycine-extended gastrin (G-17-gly) have been shown to be trophic to some gastrointestinal tumors. This in vitro study assessed the effect of G-17, G-17-gly, anti-gastrin antibodies (anti-G-17), and the CCK-B receptor antagonist PD135,158 on three hepatoma cell lines (PLC/PRF/5, HepG2 and MCA-RH7777) and an embryonic liver cell line (WRL68). The pancreatic adenocarcinoma cell line AR42J was used as a positive control. G-17 and G-17-gly caused significant proliferation of AR42J and WRL68 cell lines. G-17-gly but not G-17 induced significant proliferation of the PLC/PRF/5 cell line. Anti-G-17 and PD135,158 significantly inhibited unstimulated AR42J and WRL68 cell lines. Anti-G-17 also inhibited the proliferative effects of G-17 and G-17-gly on AR42J, WRL68, and PLC/PRF/5 cell lines, whereas PD135,158 inhibited the proliferative effect of G-17 only. G-17 and G-17-gly as well as anti-G-17 and PD135,158 had no effect on HepG2 and MCA-RH77777 cell lines. It is concluded that G-17-stimulated proliferation is mediated via the CCK-B receptor and G-17-gly via a separate, as yet uncharacterized, receptor. There may therefore be a role for gastrin in embryonic hepatocellular proliferation and perhaps also in the proliferation of some hepatocellular tumors.

Animals↗

New therapeutic options of carcinoid syndrome metastatic to the liver.

Carcinoid syndrome is a relatively rare disease, generally associated with poor prognosis. Conventional diagnostic and therapeutic methods often prove inadequate and ineffective. New therapeutic options have recently been provided by Radiolabeled long-acting somatostatin analogs (Octreotide), alpha interferon, 131 MIBG and non-pharmacological methods--embolization of the hepatic artery, gene therapy, and combined therapies.

3-Iodobenzylguanidine↗

Expression and processing of gastrin in pancreatic adenocarcinoma.

BACKGROUND: Gastrin is a trophic hormone and promotes growth of gastrointestinal and non-gastrointestinal cancers. Studies both in vitro and in vivo have suggested that pancreatic cancer cells not only have the ability to respond to circulating forms of gastrin but also to respond to the autocrine production of gastrin and its precursors. The aim of this study was to identify the expression of CCK-B/gastrin receptor, progastrin, glycine-extended gastrin and amidated gastrin in both normal pancreas and pancreatic adenocarcinoma. METHODS: Tissue sections from patients with normal pancreas (n = 10) and pancreatic cancer (n = 22) were assessed using immunohistochemical methods for CCK-B/gastrin receptor, progastrin, glycine-extended gastrin and amidated gastrin expression. RESULTS: Normal pancreas showed no expression of receptor or gastrin isoforms except for occasional cells in the islets. Definite expression of CCK-B/gastrin receptor, progastrin, glycine-extended gastrin and amidated gastrin was observed in 95, 91, 55 and 23 per cent of sections from patients with pancreatic cancer respectively. CONCLUSION: Pancreatic cancer cells express CCK-B/gastrin receptor and gastrin precursor forms in most patients. Expression of the gastrin precursor forms is probably related to autocrine production. New therapeutic strategies need to be developed for the management of pancreatic cancer. Targeting gastrin and its receptor may provide a novel treatment option.

Adenocarcinoma↗

Expression and processing of gastrin in hepatocellular carcinoma, fibrolamellar carcinoma and cholangiocarcinoma.

BACKGROUND/AIMS: Gastrin is a trophic factor within the normal gastrointestinal tract and is also a mitogen for a number of gastrointestinal and non-gastrointestinal tumours. Precursor forms of gastrin including progastrin (proG) and glycine-extended gastrin (G-gly) as well as the fully processed amidated gastrin (G-NH2) are expressed by tumours. There has been little study of the role of gastrin in either normal liver or liver tumours. The aim of this study was to identify the expression of CCK-B/gastrin receptor (CCK-BR), proG, G-gly and G-NH2 in normal liver and liver tumours. METHODS: Tissue sections from patients with hepatocellular carcinoma, fibrolamellar carcinoma, cholangiocarcinoma as well as normal liver biopsies were assessed for expression of CCK-BR and gastrin isoforms. RESULTS: Most liver tumours express CCK-BR and are able to process gastrin as far as proG and G-gly, although not as far as the amidated form. There appears to be little expression of the receptor and no expression of precursor forms of gastrin in normal liver. CONCLUSIONS: Liver tumours express the CCK-BR and precursor forms of gastrin. This expression may be associated with tumour proliferation.

Bile Duct Neoplasms↗

Expression of CCKB/gastrin receptor isoforms in gastro-intestinal tumour cells.

Anti-serum raised against the human cholecystokinin B (CCKB)/gastrin receptor was used in Western blotting to differentiate the cellular locations of receptor isoforms expressed by human gastro-intestinal (GI) tumour cell lines. Using anti-serum directed against the amino-terminal extracellular tail of the CCKB/gastrin receptor, 8/9 cell lines were shown to express immunoreactive proteins of either m.w. 70 or 40 kDa, or both. Both isoforms were found to be associated with intracellular, non-nuclear membranes, whereas only the 70 kDa protein was expressed in the plasma membrane. Receptor expression was related to gastrin production and secretion. Both progastrin and glycine-extended gastrin-17 were produced and secreted by the tumour cell lines; however, carboxy amidated gastrin was not detected by radioimmunoassay. A CCKB/gastrin receptor transfectant NIH3T3 cell line did not produce detectable gastrin and showed exclusive expression of the 70 kDa receptor on the plasma membrane. One cell line had <50 pg/ml cell-associated progastrin and no detectable receptor form. Cell lines expressing 50-150 pg/ml had both 40 and 70 kDa receptor forms. Those expressing >150 pg/ml progastrin had only the 40 kDa isoform, which was shown to be exclusively expressed on intracellular, non-nuclear membranes, in one of the cell lines. Of the 4 cell lines exclusively expressing the lower m.w. receptor, 3 had gastrin present within the cell, which was not secreted. Thus, if cell-associated gastrin induces a proliferative effect, it may be by an intracrine pathway. Our study has identified the presence of CCKB/gastrin receptor isoforms in different cellular locations and may help toward understanding the complex autocrine and intracrine pathways mediated by gastrin peptides.

3T3 Cells↗

Gastric carcinoid expresses the gastrin autocrine pathway.

BACKGROUND: In gastric adenocarcinoma the gastrin autocrine-paracrine pathway is activated. As enterochromaffin-like (ECL) cells originate from the same stem as epithelial cells, the aim of this study was to determine if the gastrin autocrine pathway is present in gastric carcinoid. METHODS: Samples from ten patients with gastric carcinoid were assessed by immunocytochemistry using primary antibodies directed against gastrin precursors and the gastrin/cholecystokinin B receptor and detected using the avidin-biotin immunoperoxidase system. RESULTS: A high level of expression of precursor and mature gastrin peptides, together with the gastrin receptor, was seen in all carcinoids screened. CONCLUSION: In common with the glandular epithelium of the stomach the gastrin gene is activated during the neoplastic process in ECL cells. This finding may explain why some carcinoids do not regress after surgical procedures that lower serum gastrin. Antigastrin agents may be a useful treatment for carcinoid either in their own right or as an adjunct to surgery.

Adult↗

Relationship between radiological classification and the serological and haematological features of untreated pulmonary tuberculosis in Indonesia.

Immunological and metabolic responses were studied in 110 patients with newly diagnosed pulmonary tuberculosis and 32 healthy controls from similar socioeconomic backgrounds. The severity of lung involvement was assessed radiologically, but this was not related to the current features of cell mediated immunity or to those of many aspects of the serological response to Mycobacterium tuberculosis. However, the patients with more extensive pulmonary tuberculosis showed higher titres of IgG2 antibody to whole killed M. tuberculosis and to the ML34 epitope shared by many species of mycobacteria. The patients with more extensive pulmonary tuberculosis showed a more marked metabolic response to infection as manifested by changes in serum levels of acute phase reactant proteins. Accordingly, the metabolic responses are considered to be more likely to prove of value in clinical monitoring of patients for severity of infection, or of reactivation of infection with M. tuberculosis, than immunological responses.

Acute-Phase Proteins↗

Pulmonary necrobiotic nodules without rheumatoid arthritis.

Pulmonary necrobiotic nodules are the least common of the pulmonary lesions associated with rheumatoid arthritis. Histologically they are identical to subcutaneous rheumatoid nodules. Systemic rheumatoid arthritis usually precedes the development of pulmonary nodules. Seven cases where the pulmonary nodule appeared before or without the development of systemic rheumatoid arthritis are described. The typical histological and radiological features of necrobiotic nodules were found in each. In five of the seven the nodules were in more than one site and in five there were cavitating nodules. Spontaneous improvement occurred in one case. Pulmonary nodules preceded systemic rheumatoid arthritis in three cases and in the remaining four cases systemic rheumatoid arthritis has not yet appeared despite prolonged follow-up. In all patients, tests for rheumatoid factor have remained negative. The absence of circulating rheumatoid factor and systemic rheumatoid arthritis cannot exclude the diagnosis in these cases if the histological diagnosis is accepted as conclusive.

Adult↗