Ornithine decarboxylase is important in intestinal mucosal maturation and recovery from injury in rats

A transient increase in ornithine decarboxylase activity and polyamine biosynthesis occurs in the intestinal mucosa of the newborn rat in the third week after birth. During this period, there is a rapid conversion of the mucosa from a fetal to a mature adult status. A similar increase in ornithine decarboxylase activity also accompanies the rapid recovery of the mucosa 1 week after an injury is induced by chemotherapy in adult rats. In vivo, alpha-difluoromethyl ornithine, a highly selective, enzyme-activated, irreversible inhibitor, suppresses these increases in mucosal ornithine decarboxylase and delays both intestinal mucosal maturation and recovery from injury. Thus increased ornithine decarboxylase activity, with the resultant increase in polyamine content, may play an essential role in intestinal mucosal maturation and regeneration in the rat.

Anaplastic variants of medullary thyroid carcinoma: a light-microscopic and immunohistochemical study

Three unusual cases of anaplastic medullary thyroid crcinoma, two having small cell characteristics and one having the features of an anaplastic giant-cell carcinoma, were encountered during a review of 110 cases of familial and sporadic medullary carcinoma. Immunoperoxidase demonstration of calcitonin within tumor cells in these three cases enabled differentiation of the two small cell variants from lymphoma or other small cell carcinomas, and differentiation of the anaplastic giant-cell variant from other giant cell carcinomas of the thyroid. Although the existence of small cell carcinomas of the thyroid gland has been questioned, this study shows that small cell carcinomas of the thyroid gland do exist and that at least some are variants of medullary carcinoma. Whereas previous immunohistochemical studies have been successfully employed in defining the spectrum of C-cell proliferative disorders and in understanding the evolution of medullary thyroid carcinoma, this study demonstrates the value of these techniques in diagnostic pathology. Immunoperoxidase staining can be successfully used in differentiating unusual variants of medullary carcinoma from other thyroid tumors.

Age-related abnormalities of circulating polyamines and diamine oxidase activity in cystic fibrosis heterozygotes and homozygotes

Serum putrescine (Pu), spermidine (Sd), spermine (Sp), and plasma diamine oxidase ativity (DAO) were determined in cystic fibrosis (CF) homozygotes and heterozygotes plus age-matched controls. Mean (+/- S.E.) levels of Pu (0.51 +/- 0.06 nmoles/ml), Sd (0.63 +/- 0.07 nmoles/ml), and Sp (0.33 +/- 0.08 nmoles/ml) were higher (P < 0.001) in 17 control children versus 16 healthy adults (Pu = 0.15 +/- 0.04; Sd = 0.14 +/- 0.03; Sp = 0 in all). All 4 CF adults tested, but only 3 of 24 CF children, had increased polyamines relative to age-matched controls. Pu (0.33 +/- 0.04), Sd (0.33 +/- 0.05) and Sp (0.16 +/- 0.12) were increased (P < 0.001) in 11 adult heterozygotes; in turn, Pu (0.56 +/- 0.11; P < 0.025) and Sd (0.86 +/- 0.22; P < 0.005) were higher in the adult CF patients than in the heterozygotes. Plasma DAO was higher (P < 0.001) in 45 control children (9.3 +/- 0.7 units/ml) versus 61 healthy adults (5.7 +/- 0.07). Levels greater than or equal to +2 S.D. for controls occurred in 8 (21%) of 39 CF patients. Plasma DAO (19 +/- 4.8) was increased (P < 0.001) in 27 adult heterozygotes; 10 (37%) had values greater than or equal to +2 S.D. for normal adults. One or more polyamines and/or DAO were increased in each of 11 heterozygotes in whom all parameters were measured. These composite abnormalities might be considered as a potential means for identification of asymptomatic CF heterozygotes.

Diamine oxidase (histaminase). A circulating marker for rat intestinal mucosal maturation and integrity

Diamine oxidase (histaminase) is an enzyme found in high concentrations in the intestinal mucosa of humans and other mammalian species. We investigated whether plasma and mucosal levels of diamine oxidase activity reflect both the maturational status of the mucosa during its development in the newborn rate and the degree of mucosal damage during its injury in the adult rat. Litter mates were reared under identical conditions and killed at different ages from day 0 to day 40 after birth. Diamine oxidase in the small intestine was low at birth, increased gradually with age, reached a peak at 22 d, and then remained at normal adult levels, similar to the developmental patterns of maltase and sucrase. Plasma diamine oxidase rose in parallel with intestinal levels (n = 500, r = 0.84, P less than 0.001), reached a peak at 24 d, and then remained at normal adult levels. Diamine oxidase activity in 15 nonintestinal tissues was less than 5% of ileal mucosal activity, and no nonintestinal activities showed increase with age. Adult rat intestinal loops were perfused with hyperosmolar sodium sulfate solutions to produce selective damage to villus mucosa. With increasing mucosal damage, there was a progressive decrease in the enzyme activities studied; first, lactase levels fell, then maltase and sucrase, and finally mucosal and plasma diamine oxidase activity levels fell. The decrease in plasma diamine oxidase reflected the degree of mucosal damage (n = 29, P less than 0.04). Diamine oxidase activity is thus unique among intestinal mucosal enzymes studied to date in that circulating levels can serve as a marker of mucosal maturation and integrity.

Activities of L-dopa decarboxylase and diamine oxidase (histaminase) in human lung cancers and decarboxylase as a marker for small (oat) cell cancer in cell culture

The neuroendocrine [amine precursor uptake (decarboxylase)] properties of small (oat) cell lung cancer (SCC) have suggested that this neoplasm may have a separate histogensis from the other major types of human lung tumors. We now report that a key element of this concept, L-dopa decarboxylase activity, is present in surgical and autopsy tissues from all forms of lung cancer. Values are highest in SCC lesions; however, lung adenocarcinoma tissues can have considerable activity, and values overlap those for SCC and fall between values for SCC and large cell and squamous cell carcinoma. The distribution of diamine oxidase activity is identical except that even more overlap occurs between the major tumor types. These data may provide further evidence that SCC and other human lung cancers could share a common origin in the bronchial mucosa. In cell cuture, the distribution of the two enzyme activities is different. The average L-dopa decarboxylase activity is much higher (seven separate culture lines) than in the in vivo specimens, and it completely separates these cell lines from non-SCC lung tumors (four lines). Diamine oxidase is generally low in both SCC cells and non-SCC cells in culture and does not separate the various cell types. L-Dopa decarboxylase activity thus does appear to be a valuabe marker for separating SCC cells from other lung cancer cells in vitro.

Tumor cell origin of histaminase activity in ascites fluid from patients with ovarian carcinoma

We have demonstrated by tissue assay and immunohistochemical techniques that tumor cells appear to be the source of the increased histaminase activity found in 60% of ascitic fluids from patients with ovarian carcinoma. The histaminase activity in 64% of tumor tissues studied was greater than 100 U/g of tissue, a value higher than that for normal tissues other than kidney and intestine. The presence of elevated ascitic fluid histaminase activity (greater than 3.5 U/ml) correlates with the presence of high histaminase activity in tumor tissue. Histaminase activity is higher in ascitic fluid from the patients than it is in their plasma, probably reflecting the direct entry of histaminase into the peritoneal cavity.

Relationship of metastatic medullary thyroid carcinoma to calcitonin content of pheochromocytomas: an immunohistochemical study

Immunoperoxidase studies have been utilized to investigate further the previously reported presence of immunoassayable calcitonin in pheochromocytoma tissue from some patients with MEN II syndromes. We have been able to demonstrate calcitonin in pheochromocytoma tissue only in two patients with MEN II syndromes in whom the pheochromocytomas contained metastatic medullary thyroid carcinoma. In both cases, the calcitonin was present only in the medullary carcinoma. We have not been able to demonstrate immunoreactive calcitonin in normal adrenal glands or in pheochromocytomas of other patients with and without MEN syndromes. Adrenal medullary cells and thyroid C cells are both of neural crest origin and both possess APUD characteristics. The presence of calcitonin in medullary thyroid carcinoma cells and not in pheochromocytes has important implications with regard to cellular differentiation and peptide hormone production.

Levels of histaminase and L-DOPA decarboxylase activity in the transition from C-cell hyperplasia to familial medullary thyroid carcinoma

The distribution of calcitonin, L-dopa decarboxylase, and histaminase is studied in sectioned total thyroid glands from patients with different stages of familial medullary thyroid carcinoma. In 5 glands with gross carcinoma and in 3 with early microscopic carcinoma the distribution of all three parameters positively correlates (p less than .01 for each correlation). In contrast, in 6 glands with C-cell hyperplasia only the distribution of calcitonin and L-dopa decarboxylase correlates (r = 0.64, p less than .01) while those for histaminase vs. calcitonin (r = .17, p = N.S.) and histaminase vs. dopa decarboxylase (r = .03, p = N.S.) do not. In the glands with microscopic carcinoma the peak levels of histaminase occur in the areas of disease as defined by immunohistochemical staining of calcitonin; mean histaminase activity is the only one of the three parameters measured that distinguishes between C-cell hyperplasia and microscopic carcinoma (p less than .005). Immunohistochemical staining of histaminase shows positive cells in glands with gross and microscopic carcinoma, but in none of the glands with hyperplasia alone. Histaminase is thus found in high amounts in some malignant C-cells only and may be a useful marker to distinguish between hyperplasia and malignancy in thyroids with early C-cell proliferative disorders.

Vasoactive intestinal peptide and its relationship to ganglion cell differentiation in neuroblastic tumors

Immunohistochemical studies have demonstrated that immunoreactive vasoactive intestinal peptide is present in, and restricted to, the differentiating and mature ganglion cells in a variety of normal and neoplastic neural tissues. In a composite pheochromocytoma-ganglioneuroma (associated with the syndrome of watery diarrhea, hypokalemia, and hypochlorhydria), five ganglioneuroblastomas, five ganglioneuromas (two of which were associated with diarrheal syndromes), an unusual mixed neuroblastoma-ganglioneuroma, and four normal sympathetic ganglia, vasoactive intestinal peptide was present in differentiating and mature ganglion cells. The peptide was also demonstrated in isolated ganglion cells in two pheochromocytomas but was not present in pheochromocytes, Schwann cells, or undifferentiated neuroblastic cells in the neuroblastomas and ganglioneuroblastomas. These studies indicate that the presence and presumably the production of vasoactive intestinal peptide thus reflect a particular line of neuroblastic differentiation and are not merely a reflection of common derivation of these tissues. Our identification of vasoactive intestinal peptide in neurogenic tumors associated with diarrhea supports the contention that the peptide might be an important diarrheogenic factor in these tumors.

Hormone-mediated watery diarrhea in a family with multiple endocrine neoplasms

A father and son each presented with severe watery diarrhea. The son was found to have a pancreatic islet-cell tumor associated with the pancreatic cholera syndrome, as well as a parathyroid adenoma. The father was found to have multiple islet-cell adenomas and the Zollinger-Ellison syndrome. Pancreatic tumor tissue from each patient contained detectable gastrin and vasoactive intestinal peptide; however, a much higher gastrin concentration was found in the tumor tissue from the father and a much higher vasoactive intestinal peptide content in the tumor tissue from the son. Thus, watery diarrhea may be mediated by different hormones in families having multiple endocrine neoplasia; the precise cause of the diarrheal syndrome should be defined to ensure the proper therapy.

Distribution of beta-endorphin immunoreactivity in normal human pituitary

Recent immunohistochemical demonstration of calcitonin in rat pituitary has suggested that calcitonin, in addition to ACTH, endorphins, lipotropins, and melanocyte-stimulating hormones might be derived from a 31,000-dalton glycoprotein percursor molecule. This immunoperoxidase study demonstrates a similar distribution for beta-endorphin and ACTH immunoreactivity in human pituitary; however, the two peptides are not necessarily present in the same cells at all times. Calcitonin could not be demonstrated in human pituitary under conditions suitable for demonstration of the peptide in thyroid C cells. Weakly positive immunostaining could be obtained only with much increase in antiserum concentration and length of incubation, and higher concentrations of calcitonin were needed to abolish staining in preabsorption studies. It thus appears that the immunoreactive calcitonin in human pituitary differs from that in thyroid C cells. Likewise, we could not demonstrate immunoreactive endorphin in any developmental stage of medullary thyroid carcinoma. Our study suggests that caution should be applied in considering a physiologic role for calcitonin in the pituitary and in postulating a common peptide origin for endorphin and calcitonin in humans.

The effects of L-dopa on in vitro and in vivo calcitonin release from medullary thyroid carcinoma

The in vivo and in vitro effects of the dopamine precursor L-dopa on basal and stimulated calcitonin release from medullary thyroid carcinoma have been studied. In six studies of five patients, including 7- to 8-h control and test periods, oral L-dopa depressed basal calcitonin secretion by an average of 35%; the peak effects occurred within 30 min of drug administration and lasted for as long as 4 h. In seven of eight patients with medullary thyroid carcinoma (three infused with calcium and five with pentagastrin), L-dopa inhibited to varying degrees peak levels of stimulated calcitonin release and total calcitonin secretion; basal calcitonin levels, where directly tested, also again generally fell after L-dopa by an average of 50%. In a short term organ culture system using medullary thyroid carcinoma tissues, calcitonin secretion into the medium was linear with time for 2 h and could be stimulated by dibutyryl cAMP and pentagastrin. L-Dopa, in concentrations from 0.5--3.0 mM, inhibited basal calcitonin secretion (ranging from 25--55%). Addition of the L-dopa decarboxylase inhibitor, alpha-methyldopa, abolished the inhibitory effects of L-dopa. Another L-dopa decarboxylase inhibitor, carbidopa, stimulated calcitonin secretion in vitro; this effect may be independent of the L-dopa decarboxylase-inhibiting properties of this drug since alpha-methyldopa alone did not stimulate calcitonin secretion. It is concluded that the amine precursor L-dopa inhibits calcitonin release in patients with medullary thyroid carcinoma; the in vitro studies suggest that a portion of this effect may involve direct metabolism of L-dopa to dopamine in the tumor tissue itself. The importance of considering the uptake of amine precursors and the subsequent metabolism of these compounds as a modulating site for peptide hormone release from peripheral endocrine tissues is stressed.

Plasma immunoreactive calcitonin in lung cancer

We have measured plasma calcitonin in 135 untreated eucalemic men with lung cancer and a control/smoker population. Calcitonin levels were determined by radioimmunoassay and validated by immunoextraction. Plasma immunoreactive calcitonin moieties were purified by immunoadsorbent chromatography, treated with mercaptoethanol and urea, and characterized by gel filtration. Artifacts in human calcitonin radioimmunoassays of cancer-patient plasmas were detected by parallel plasma incubations in a salmon calcitonin radioimmunoassay system which does not detect human calcitonin and by immunoprecipitation of tracer at the end of radioimmunoassay incubations. Heating fresh plasmas to 65 degrees C for 1.5 hours reduced radioimmunoassay artifacts without loss of calcitonin moieties. Such characterization of hypercalcitoninemia in each of the histopathological types of lung cancer has raised some important questions about the interpretation of plasma calcitonin radioimmunoassay measurements in lung cancer. Based on inhibition of tracer-antibody binding, plasma calcitonin seemed to be elevated in 18% (14/80) of basal plasma samples obtained from patients with epidermoid or with anaplastic lung cancer. Unequivocal hypercalcitoninemia (heat stable, causing no inhibition of antibody-tracer binding in the salmon calcitonin radioimmunoassays, and immunoextractable with human calcitonin antibodies) was not found in any of the apparently hypercalcitoninemic plasmas from persons with epidermoid or anaplastic lung cancer. By contrast, unequivocal hypercalcitoninemia was found in 27% (15/55) of plasmas from patients with small cell carcinoma or adenocarcinoma. Most of the immunoreactive calcitonin recovered from small cell and adenocarcinoma lung cancer plasmas with unequivocally elevated calcitonin is much larger than calcitonin monomer.

Medullary thyroid carcinoma: relationship of method of diagnosis to pathologic staging

Medullary thyroid carcinoma (MTC) develops in virtually all patients affected with multiple endocrine neoplasia type II (MEN II), a disease inherited as an autosomal dominant trait. The thyroid tumor cells secrete calcitonin (CT) and the detection of elevated plasma levels (>300 pg/ml) of this hormone in MEN II kindred members strongly suggests the presence of MTC even though it may not be evident clinically. Intravenously administered calcium ion (Ca(++)) and pentagastrin (Pg) are potent CT secretagogues which are of particular value in establishing the early diagnosis of MTC. In evaluating seven kindreds with MEN II, we detected 90 patients with MTC. Depending on the method of diagnosis, they could be divided into three categories: Group 1; patients with no clinical evidence of MTC whose undetectable basal plasma calcitonin levels became elevated following intravenous Ca(++) or Pg, Group II; patients with no clinical evidence of MTC who had elevated basal plasma CT levels, and Group III; patients with clinically evident MTC. At the time of diagnosis of MTC, the patients in Group I were younger (20.5 +/- 1.9 years) than the patients in Group II (32.5 +/- 4.7 years, p < 0.005) and Group III (34.3 +/- 2.0, p < 0.00005). The incidence of residual MTC, as indicated by an elevated plasma CT level following provocative testing postoperatively, was less frequent in patients diagnosed biochemically ([6/34]; Group I, 4/26 and Group II, 2/8) than in those diagnosed clinically (Group III, 15/26, p < 0.002). Furthermore, regional nodes were involved less often in patients diagnosed biochemically ([5/28]; Group I, 2/22 and Group II, 3/6) than in those diagnosed clinically (Group III, 15/24, p < 0.02). Distant metastases were only evident in Group III patients. Patients with MEN II who had the diagnosis of MTC established biochemically rather than clinically, had a more favorable pathological stage of disease at the time of thyroidectomy. This was especially true if the biochemical diagnosis had been by provocative testing.

Provocative agents and the diagnosis of medullary carcinoma of the thyroid gland

Twenty-six patients with known or suspected medullary thyroid carcinoma (MTC) and 21 normal control subjects were tested intravenously on four separate days with calcium gluconate (CG), 2 mg Ca(++)/kg/1 min.; pentagastrin (P), 0.5 ug/kg/ 5 sec.; calcium chloride (CC), 3 mg Ca(++)/kg/10 min.; and a combination of calcium gluconate and pentagastrin (CG + P). Calcitonin (CT) levels were determined by radioimmunoassay on plasma collected before and immediately following each test infusion. In none of the 21 control subjects was there a clear increase in CT above 200 pg/ml following any of the four provocative tests. Conversely, in all 26 patients with known or suspected MTC, plasma CT levels were markedly increased (>300 pg/ml) following the combined infusion of CG + P. The peak CT response was greater with CG + P than with a) CG alone (22 of 24 patients, p < 0.002), b) P alone (25 of 26 patients, p < 0.002), or c) CC alone (17 of 17 patients, p < 0.002). Of 12 MTC patients with undetectable basal calcitonin levels, all had peak responses greater than 300 pg/ml following CG + P, whereas such responses occurred less often following CG alone (8 of 12) or P alone (8 of 12). The results demonstrate that the combined administration of pentagastrin and calcium gluconate constitutes a more effective and reliable stimulus for CT secretion from MTC cells than the use of either agent alone, and appears the most useful single screening test for the detection of occult MTC.

Variable content of histaminase, L-dopa decarboxylase and calcitonin in small-cell carcinoma of the lung. Biologic and clinical implications

To ascertain whether the content of endocrine markers is constant in small-cell carcinoma of the lung, levels of three markers of medullary thyroid carcinoma were studied in this tumor. Histaminase was increased in six of six primary tumors (three to 14,000 times), L-dopa decarboxylase in four of six (six to 30 times), and calcitonin in one of one (eight times) over levels in adjacent lung. Marker levels in mediastinal metastases reflected those in primary tumors in four of five patients. However, in four of seven, multiple hepatic metastases contained low to absent levels despite simultaneously high values in chest lesions. Immunohistochemical studies of histaminase revealed that within each primary tumor different cells contained different amounts of the enzyme. Since marker content varied between tumor cells, between primary tumors and between metastases in individual patients we conclude that circulating levels of these three markers cannot be expected necessarily to mirror tumor burden in patients with small-cell lung tumors.

Association of diamine oxidase and ornithine decarboxylase with maturing cells in rapidly proliferating epithelium

Diamine oxidase and ornithine decarboxylase activities are shown to have a parallel distribution across rat small intestine mucosa; levels of both enzyme activities are sharply higher in mature cells in the villus tip region than in proliferating cells in the crypt areas. Histidine decarboxylase levels were not measurable in the same cell preparations and aromatic-L-amino-acid decarboxylase activity was distributed in an opposite pattern to diamine oxidase and ornithine decarboxylase. The results suggest that intestinal diamine oxidase could be involved with polyamine metabolism. The new findings for ornithine decarboxylase suggest an in vivo role for polyamines in non-proliferative cells; rat small intestinal mucosa may be an excellent model for investigating the function of polyamines in regenerating cells.

Calcitonin and histaminase in C-cell hyperplasia and medullary thyroid carcinoma. A light microscopic and immunohistochemical study

The thyroid glands of 13 patients with gross medullary thyroid carcinoma (4 sporadic, 9 familial), 3 patients with clinically occult microscopic carcinoma, and 5 patients with C-cell hyperplasia have been studied using routine light microscopy and immunohistochemical techniques. The morphologic features of the spectrum of C-cell proliferative lesions are reviewed, and the distribution of calcitonin and histaminase in these lesions is compared. Calcitonin production is a property of normal, hyperplastic, and neoplastic C cells, and the hormone is present in the majority of tumor cells in medullary carcinoma. In contrast, histaminase is shown to be present only in some cells in medullary carcinoma and not in normal or hyperplastic C cells. We believe that the presence of histaminase in a C-cell proliferative lesion is an atypical phenomenon and indicative of malignancy.

Response of plasma histaminase activity to heparin in normal subjects and in patients with small cell carcinoma of the lung

Plasma histaminase (PH) activity only partially reflected the consistently high activity of histaminase in tumor tissue of patients with small cell carcinoma of the lung (SCC). To determine whether heparin might release histaminase from tumor tissue into the circulation as it does from some normal tissues, we studied the response of PH activity to small doses of heparin in 41 patients with SCC and in 57 normal subjects. In patients with SCC, the initial mean PH activity (2.0 U/m) was not different from that in normal subjects (1.7 U/ml). After heparin administration, the mean PH activity was no different between the 2 groups (patients with SCC, 3.1 U/ml; normal subjects, 3.5 U/ml). In both groups, the higher the initial PH activity, the greater the magnitude of the PH activity response to heparin. This relationship was linear (normal subjects, r = 0.88; patients with SCC, r = 0.91). However, in patients with SCC, the increase in post-heparin PH activity, as related to the basal levels, was significantly less than that in normal subjects (P less than 0.001 by analysis of covariance). The data suggested that heparin did not affect the release of histaminase from tumor tissue into plasma to the same degree as it promoted the enzyme's entry from normal tissue sources. The differences between the groups may enable us to differentiate between selected patients with SCC and normal subjects with borderline high PH activity values.