Distribution of plasma glucagon immunoreactivity in a patient with suspected glucagonoma

Gel filtration of plasma from a patient with a clinical syndrome of glucagonoma and a total plasma glucagon level of 2600 pg/ml, revealed the four glucagon immunoreactive fractions found in normal subjects. The total hyperglucagonemia observed was due to high levels of true glucagon and proglucagon moieties. The so-called "big plasma glucagon" (BPG) measured 190 pg/ml (normal average 113 +/- 79 pg/ml, Mean +/- SD, N = 10); the large glucagon immunoreactivity, LGI (9000 mol wt), measured 625 pg/ml (normal average 11 +/- 16 pg/ml); the true glucagon accounted for 1435 pg/ml (normal average 31 +/- 29 pg/ml); and the small glucagon immunoreactive fraction (approximately 2000 mol wt) measured 35 pg/ml (normal average 26 +/- 18 pg/ml). The high levels of LGI, considered a candidate for proglucagon, may reflect the increased secretory activity of the tumor.

[Conversion of proinsulin into insulin in insulin producing tumors in man]

The enzymatic activity of tissues of insulomas and also the proinsulin and insulin content in them was studied. As revealed, insulomas contained an increased amount of proinsulin in comparison with the unaffected islands of Langerhans. The tumours under study also differed by the capacity to catalyze the splitting of hippuryl-L-arginine, synthetic substrate of carboxypeptidase B. Proinsulin content in the tumours of the islar tissue depended on the presence in them of an enzyme catalyzing the splitting of the substrate at pH 6.8--7.2, this pointing to its participation in the conversion of proinsulin into insulin.

Simultaneous ectopic production of parathyroid hormone and calcitonin

Two patients with cancer were evaluated in whom there was evidence for the simultaneous ectopic production of parathyroid hormone (PTH) and calcitonin (CT). One patient had a gastric carcinoid and the other had a pancreatic islet cell carcinoma. Abnormal concentrations of parathyroid hormone and calcitonin were demonstrated by radioimmunoassay in the peripheral blood of each patient and in the gastric tumor. In the pancreatic tumor, immunohistologic studies also demonstrated the presence of CT and PTH and suggested that each hormone was produced by different cells of the tumor. Plasma concentrations of the hormones responded to functional tests of secretion and to tumor chemotherapy. These studies demonstrate the simultaneous ectopic production of the two physiologically antagonistic hormones, PTH and CT, and confirm their value as diagnostic markers for several types of malignancies.

[Malignant nesidioma with 2 types of secretory granules in tumor cells]

A case has been described of a male aged 38 with a malignant nesidioma. The clinical examination disclosed marked hepatomegaly, variable hypertension associated with cool sweating, agitation and transient hyperglycaemia. The primary tumour as well as the metastases in the liver weighing over 13 kg were histologically of trabecular structure and stained positively with the methods of Bodian and grimelius. The impregnation for D-cells according to Rohoznická and Vortel was positive in isolated cells only. Ultrastructurally, the tumor cells could be divided in two types. The more numerous Type I cells contained rather small secretory granules morphologically resembling A granules of islet cells, and staining positively with impregnation methods for A-cells on the ultrastructural level. Type II cells contained, in addition to the formerly described ones, another type of granules appearing as large, slightly osmiophilic ones characteristic of the D-cells of Langerhan's islets and positive with the impregnation methods for D-cells. The type II tumour cells must be therefore regarded as a mixed cell type containing two types of secretory granules.

Monolayer cell culture of human pancreatic beta cell tumor: effect of glucose and somatostatin on insulin release

A human pancreatic beta cell tumor was maintained in monolayer cell culture for 80 days. The culture was terminated because of bacterial infection. Probably because extensive trypsin-collagenase dissociation was unnecessary, the dissociated cells attached much more quickly to the surface of the culture flask than do rat pancreatic cells obtained by enzymatic dissociation. Insulin release not only oscillated widely during the first 40 days of culture but also showed a decline from 380 mU the first week to about 50 mU/week the seventh week. For some unknown reason fibroblast overgrowth was not a major problem. Reduction of the medium glucose concentration from 16.5 mM to 5.5 mM did not alter insulin release rate. At glucose concentration of 16.5 mM, somatostatin 1.0 mug/ml reduced insulin release by 40%. From our previously reported studies on the effect of somatostatin on insulin release by monolayer cell cultures of rat endocrine pancreas, we conclude that the constant release of insulin by the tumor cells is relatively nonstimulated. We have confirmed that monolayer cultures of human pancreatic beta cell tumor do not represent a good model for normal human beta cell function because of the major shortcoming of an apparent inability to recognize glucose as a secretogogue.

A rapid method of relating protein to flow in human pancreatic secretions

A method of obtaining linear plots of protein-flow data from human pancreatic ductal secretions is described. The protein concentration in pancreatic secretions, when related to flow rates in two individuals, gave similar regression lines, with the correlation coefficients or r = -0.97 and -0.98, respectively, and slopes m = -1.02 and -0.82.

Ocular pathology in the elfin face syndrome (the Fanconi-Schlesinger type of idiopathic hypercalcaemia of infancy). Histochemical and ultrastructural study of a case

The pathology, particularly the ocular pathology, is described in a 42-year-old mildly retarded man with a history of vomiting in infancy. He had an elfin-like face. He died having a pancreatic carcinoma. At autopsy, a supravalvular aortic stenosis and a hypoplastic aorta found clinically were confirmed. Stainings for calcium were positive in the aortic wall, the kidneys, the adrenals and the spleen. In the eyes, calcium was found in the corneal epithelium and endothelium, in corneal keratocytes and stroma, in conjunctival epithelium and in the sclera. Electron microscopy of the eyes revealed that calcium was deposited as hydroxyapatite intracellularly in aggregations of needle-like crystals and extracellularly as spherules morphologically different from the intracellular deposits. Although the serum values of calcium in this patient were normal during his adult life, the histopathological examination indicates an earlier period of raised serum calcium. We find it probable that he had idiopathic hypercalcaemia in infancy, thereby connecting this infantile condition with the elfin face and supravalvular aortic stenosis. In similar cases, the use of the above-mentioned technique is recommended for revealing abnormal calcium storage post-mortem and in vivo (by conjunctival biopsy) in order to substantiate the diagnosis of hypercalcaemia.

Evidence for secretion of vasoactive intestinal peptide by tumours of pancreas, adrenal medulla, thyroid and lung: support for the unifying APUD concept

Levels of vasoactive intestinal polypeptide (VIP) were measured by radioimmunoassay in plasma or tissue from thirty-five patients with watery diarrhoea, and in plasma of twenty-five normal controls. Plasma levels were between 0.6 and 11.0 ng/ml in thirty-one of the thirty-three patients in whom it was measured and too low to measure (less than 200 pg/ml) in the other two. Peptide levels were less than 200 pg/ml in twenty-three of the controls, but higher in the remaining two. All tissues from patients were "rich" in VIP (10 ng to 35 microgram per g). The aetiologic diagnoses included pancreatic islet-cell adenoma or adenocarcinoma, islet-cell hyperplasia, bronchogenic carcinoma, pheochromocytoma, ganglioneuroblastoma, medullary thyroid carcinoma, and retroperitoneal histiocytoma. The findings support the conclusions that: (1) VIP is a likely mediator of the water-diarrhoea syndrome; (2) the syndrome may result from a variety of tumours; (3) this or a related peptide hormone may be secreted by these tumours; and (4) these tumours may have a common embryonic origin.

Islet cell carcinoma, pancreatic cholera, and vasoactive intestinal peptide

Three patients with profuse diarrhea, hypokalemia, metastatic nonbeta islet cell carcinoma, and the absence of gastric hypersecretion were found to have elevated levels of vasoactive intestinal peptide. One patient also had elevated serum gastrin levels. Two patients experienced prolonged remissions of diarrhea after operations in which only tumor biopsies were done. These cases further implicate vasoactive intestinal peptide as the agent mediating the diarrhea in the syndrome of pancreatic cholera.

Portal and pancreatic vein catheterization with radioimmunologic determination of insulin

Percutaneous transhepatic catheterization of the portal vein along with the catheterization of the aorta and the vena cava was performed in six patients, one of whom had hypoglycemic attacks due to Whipple's triad. Blood samples from different branches in the different vessel systems were withdrawn for radioimmunologic determination of insulin. By this method, preoperative localization of the insulin producing pancreatic islet cell tumor was su-cessfully performed. Multiple tumors as well as liver metastases were preoperatively excluded. Recatheterization and blood sampling for radioimmunologic determination of insulin was performed postoperatively to verify the radicality of the operation. Insulin concentrations from the hypoglycemic patients were compared with those of the patients without insulinoma and found to be significantly higher. The procedure is proposed as a useful method for localizing all types of gastrointestinal hormone producing primary or secondary tumors in which a method for hormone determination is available. The postoperative investigation is useful as a check of the operation performed and as a follow-up examination for the early diagnosis of recurrence.

Role of insulin and glucose in the induction of hypoaminoacidemia in man: studies in normal, juvenile diabetic, and insuloma patients

It is generally assumed, but not established, that the lowering of plasma free amino acid levels following glucose intake is entirely mediated by stimulated insulin secretion. This problem was investigated in groups of healthy volunteer subjects, juvenile diabetics, and insuloma patients. The plasma concentrations of 15 individual free amino acids, glucose, and insulin or C-peptide were determined before and at intervals after either oral glucose (75 Gm.) or intravenous glucose (0.25 Gm. per kilogram of body weight) or tolbutamide (1 Gm.). Glucose lowered plasma amino acid levels in both situations of stimulated (healthy volunteer subjects) and absent (diabetic) insulin secretion. The lack of insulin response in juvenile diabetics was evident by the lack of any significant increase in C-peptide levels following glucose ingestion. Nevertheless, despite markedly greater plasma glucose levels, hypoaminoacidemia was less severe in diabetics than in normal volunteer subjects. In comparison to healthy volunteer subjects who showed significant decreases in concentrations of 14 of 15 examined amino acids by glucose, the diabetic individuals exhibited significant decreases in concentration of 8 amino acids (leucine, isoleucine, valine, tyrosine, phenylalanine, methionine, citrulline, and arginine). In face of a massively greater insulin response in an insuloma patient (greater than 1,000 muU per milliliter), the decreases in the levels of individual free amino acids following glucose were within the range of values obtained in the normal volunteer subjects. The stimulation of insulin secretion with tolbutamide also lowered the concentrations of free amino acids in plasma. However, one importnat difference distinguished the effect of tolbutamide from that of glucose. Within a few minutes after the injection of tolbutamide, there was a marked and persistent fall in alanine levels, while during the entire course of the glucose tolerance test there were no significant changes in the level of this amino acid, suggesting a difference in the mechanism of hypoaminoacidemia induced by endogenous insulin in the presence or absence of exogenous glucose. Despite a markedly greater insulin response to tolbutamide in the insuloma patient (greater than 1,500 muU per milliliter), the decreases in plasma glucose and free amino acid levels fell within the range of values obtained in normal volunteer subjects. In conclusion, the exogenous glucose per se lowers the levels of free amino acids in plasma. This effect is enhanced by insulin.

Pancreatic cholera. Sudies on tumoral secretions and pathophysiology of diarrhea

Tumoral secretions and pathophysiology of diarrhea were studied in 1 patient with pancreatic cholera. High concentrations of vasoactive intestinal peptide were found in both systemic blood and tumoral extracts, together with increased plasma levels of calcitonin and protaglandins E and Falpha. Gastric inhibitory peptide and gastrointestinal and pancreatic hormones were absent from the tumor, except for small amounts of glucagon, and their blood levels were normal. Decreased basal but normal pentagastrin-stimulated gastric acid secretion, normal basal and secretin-stimulated pancreatic secretion, increased volume of gallbladder bile with high bicarbonate, and low bile salt concentrations were observed, but the electrolyte content and flow rate of fluid passing the duodenojejunal junction were within normal limits. Small intestine was found to be the origin of the water and electrolyte fasting losses. Jejunum was the site of bicarbonate secretion. Jejunal glucose and leucine-stimulated water and sodium transports were also strikingly decreased, whereas the absorption rates of the sugar and amino acid were normal. Colon reabsorbed high amounts of water and sodium but increased potassium losses. Biological effects of vasoactive intestinal peptide may explain most of the patient's upper digestive secretion abnormalities and small intestinal function impairments, whereas secondary aldosteronism might explain the modified colonic function.

Pancreatic cholera (W.D.H.A. syndrome). Histochemical and ultrastructural studies

Results of light and electron-microscopic studies of primary pancreatic tumor and of metastasis in a new case of Pancreatic Cholera (P.C.) are reported. The primary tumor but not the metastases, contained unusual, large cystic glandular formations, lined both by pancreatic-duct- and small-intestine-like epithelia and closely connected with the endocrine proliferation. A part from a few D-cells, the endocrine tumoral cells could not be identified by histochemical stainings. Their ultrastructural pattern, with small secretory granules (diameter less than 300 nm) and numerous cytoplasmic bunches of filaments, was very similar to that of gastric and duodenal D1-cells. Normal duodenal D1-cells have been said to produce gastric inhibitory peptide, a substance structurally and biologically similar to the vasoactive intestinal peptide actually secreted by the tumor. The normal histological appearance of gastric, gallbladder, jejunal, ileal, right and left colonic mucosae is consistent with the responsibility of the tumoral secretion in the impairment of gut functions in P.C.

Disordered glucose and insulin metabolism in patients with insulinoma

The response of plasma glucose and insulin to infusion of glucose and of epinephrine plus propranolol were examined in normal subjects and in two patients with surgically proven insulin-secreting islet cell tumors. The plasma immunoreactive insulin concentration in the two patients was both inappropriate and independent of the plasma glucose concentration. Their insulin secretion was neither increased by physiologic stimulants nor decreased by pharmacologic inhibitors of insulin secretion. There are diagnostic uses for these data as well as theoretical implications. We propose a physiological approach to establish the diagnosis of insulin-secreting islet cell tumors.

Serum alpha-fetoprotein in patients with neoplasms of the gastrointestinal tract

Serum alpha-fetoprotein levels were measured by a sensitive double-antibody radioimmunoassay in 580 patients with a variety of malignant and nonmalignant gastrointestinal diseases to determine the incidence of levels elevated above 40 ng/ml. Over 200 normal control subjects have all had levels below 40 ng/ml. Fifteen % of 95 patients with gastric carcinoma, 3 percent of 191 patients with colorectal carcinoma, 24 percent of 45 patients with pancreatic carcinoma, 25 percent of 8 patients with biliary tract carcinoma, and 70 percent of 73 patients with hepatocellular carcinoma had elevated serum alpha-fetoprotein. None of 14 patients with esophageal or small bowel carcinoma had elevated levels. In contrast, 1 percent of 154 patients with nonmalignant, nonhepatic gastrointestinal disease had elevations of serum alpha-fetoprotein. Alpha-Fetoprotein appears to be a potential marker for tumor activity in some patients with certain gastrointestinal cancers.

[The vaso-active intestinal polypeptide in Verner-Morrison syndrome]

A 40-year-old man with the Verner-Morrison syndrome (refractory watery diarrhoea and hypokalaemia in islet-cell tumour of the pancreas) had an islet-cell carcinoma of the non-B-cell type with metastases to liver and mesenteric lymph nodes. High concentrations of a vasoactive intestinal polypeptide (VIP) were demonstrated in tumour tissue and plasma by radioimmunological tests. After surgical removal of the tumour the plasma VIP concentration fell to normal. Immunohistochemical tests of the tumour for gastrointestinal hormones demonstrated marked fluorescence only for vaso-active intestinal polypeptide. It is assumed that this polypeptide is largely responsible for the clinical signs. In the described case the severe watery diarrhoea ceased after glucocorticoid administration.

Formaldehyde-ozone-induced fluorescence in gastrin-producing tumours

Material from eight peptide hormone-secreting tumours, extirpated from the pancreas or from the antrum-duodenum region, was examined. Four of the patients had the clinical manifestations of the Zollinger-Ellison syndrome, two showed the features of an insulin-secreting tumour and one had a glucagonoma. Gastrin-producing cells, identified by immunohistochemistry, were found in five of the tumours. These cells displayed a varying degree of formaldehyde-ozone-induced fluorescence. This agrees with previous observations on the gastrin cell of human antral and duodenal mucosa. From model experiments, formaldehyde-ozone-induced fluorescence is thought to reflect the presence of peptides having tryptophan in the NH2-terminal position. The nature of this peptide in gastrin-producing cells is unknown.

Gastric acid secretion in pancreatic disease

Gastric acid secretion studies were carried out in 48 patients with pancreatic disease and in 20 control subjects. The mean basal and maximal outputs were lower in the patients than in control subjects. The present study indicates that such patients are not likely to suffer from gastric hypersecretion and peptic ulceration.

Maximum bicarbonate response to intravenous infusion of 'GIH' secretin in man

1. In twenty-one tests in six subjects without, and three with, pancreatic disease, the maximum volume and bicarbonate output of the duodenal aspirate in response to intravenous infusion of pure ‘GIH’ secretin was significantly higher with 4 than with 2 units kg−1 h−1, and there was no consistent change in these outputs after 8 units kg−1 h−1.

2. The optimum maximum dose of secretin in man is probably 4 units kg−1 h−1.

Ectopic production of the isolated beta subunit of human chorionic gonadotropin

A material similar to the beta subunit of human chorionic gonadotropin (hCG-beta) was detected in serum (300 ng/ml) and tumor extract from a 75-yr-old man with pancreatic adenosquamous carcinoma. This material was indistinguishable from hCG-beta in three different types of radioimmunoassay that displayed widely varying reactions with glycoprotein trophic hormones and their subunits. In gel chromatography there appeared to be heterogeneity of the serum beta-like immunoactivity, including one component that coeluted with standard hCG-beta tracer and another immunologically indistinguishable component that displayed a slightly lower elution volume. Neither complete human chorionic gonadotropin (hCG) nor its alpha subunit was detected in radioimmunoassays of serum, before or after fractionation, or in tumor extract. The absence of complete hCG was confirmed in a gonadotropin bioassay sensitive to 15 ng of hCG, which showed no bioactivity in serum or tumor extract containing 450 and 90 ng of hCG-beta, respectively. This case probably represents the first demonstration of isolated polypeptide subunit production of ectopic origin and suggests that hCG-beta, as well as other subunits, may prove useful as cancer markers.