Preliminary evaluation of gastric endocrine cells in rats with experimental uremia

Chronic renal failure can be the cause of various disturbances in hormonal and electrolyte metabolism, including calcium and phosphate metabolism. The aim of this study was the evaluation of pyloric endocrine cells in Wistar rats with experimental uremia. Fragments of gastric pylorus were collected 30 days after nephrectomy. Paraffin embedded sections were stained with H+E and by silver impregnation. We also performed immunohistochemical reactions with the use of specific antibodies against calcitonin gene-related peptide (CGRP), synaptophysin (SY), somatostatin (ST), and neuronal specific enolase (NSE). The rats with experimental uremia showed an increase in the number of endocrine cells and in intensity of all the examined reactions.

Pancreatic tumours: molecular pathways implicated in ductal cancer are involved in ampullary but not in exocrine nonductal or endocrine tumorigenesis

Alterations of K- ras, p53, p16 and DPC4/Smad4 characterize pancreatic ductal cancer (PDC). Reports of inactivation of these latter two genes in pancreatic endocrine tumours (PET) suggest that common molecular pathways are involved in the tumorigenesis of pancreatic exocrine and endocrine epithelia. We characterized 112 primary pancreatic tumours for alterations in p16 and DPC4 and immunohistochemical expression of DPC4. The cases included 34 PDC, 10 intraductal papillary-mucinous tumours (IPMT), 6 acinar carcinomas (PAC), 5 solid-pseudopapillary tumours (SPT), 16 ampulla of Vater cancers (AVC) and 41 PET. All tumours were also presently or previously analysed for K- ras and p53 mutations and allelic loss at 9p, 17p and 18q. Alterations in K- ras, p53, p16 and DPC4 were found in 82%, 53%, 38% and 9% of PDC, respectively and in 47%, 60%, 25% and 6% of AVC. Alterations in these genes were virtually absent in PET, PAC or SPT, while in IPMT only K- ras mutations were present (30%). Positive immunostaining confirmed the absence of DPC4 alterations in all IPMT, SPT, PAC and PET, while 47% of PDC and 38% of AVC were immunonegative. These data suggest that pancreatic exocrine and endocrine tumourigenesis involves different genetic targets and that among exocrine pancreatic neoplasms, only ductal and ampullary cancers share common molecular events.

Absence of a PDX-1 mutation and normal gastroduodenal immunohistology in a child with pancreatic agenesis

Pancreatic agenesis is a rare condition, of which only a limited number of cases have been described. One recent paper reported a homozygous mutation in the pancreatic duodenal homeobox gene 1 (PDX-1) in a child with pancreatic agenesis. We report a 6-year-old boy with pancreatic agenesis, treated medically, without abnormalities in the PDX-1 gene coding sequence and with normal gastroduodenal endocrine cell distribution. Genes other than PDX-1 also appear to be involved in human pancreatic agenesis.

Improved estimation of the pair correlation function of random sets

The texture of binary spatial structures can be characterized by second-order methods of spatial statistics. The pair correlation function, which describes the structure in terms of spatial correlation as a function of distance, is of central importance in this context. Conventionally, the pair correlation function of stationary and isotropic random sets is estimated as the ratio of the covariance to the square of volume fraction of the phase of interest. In the present paper, an improved estimator of the pair correlation function is presented, where the covariance is divided by the square of a distance-adapted estimator of volume fraction. The new estimator is explained mathematically and applied to simulated images of the Boolean model and to microscopic images from neoplastic and non-neoplastic human glandular tissues. It leads to a considerable reduction of bias and variance of estimated pair correlation functions, in particular for large distances.

Adenylyl cyclase isoform expression in non-diabetic and diabetic Goto-Kakizaki (GK) rat pancreas. Evidence for distinct overexpression of type-8 adenylyl cyclase in diabetic GK rat islets

Glucose-induced insulin release is markedly decreased in the spontaneously diabetic Goto-Kakizaki (GK) rat pancreas. This defect was recently shown to be reversed by forskolin which markedly enhances cAMP generation in GK islets. These effects of forskolin were associated with overexpression of type-3 adenylyl cyclase (AC) mRNA due to the presence of two functional point mutations in the promoter region of AC3 gene in GK rat. Nine AC isoforms have been described, but their expression pattern in relation to the main pancreatic islet cell types, as well as their involvement in the diabetic state, is still unknown. Using antibodies raised against AC1-8, we have studied by double immunofluorescence the localisation of these AC isoforms in different endocrine cell types in both normal and diabetic GK rat pancreas. Our results demonstrated a clear immunoreaction (IR) to AC1-4 and 6 in normal and GK islet beta-cells, while a smaller number of ACs were expressed in alpha- and delta-cells. No AC-IR was observed in pancreatic polypeptide cells. Moreover, we have found an increased IR of the Ca2+-stimulated ACl, AC3 and AC8 in diabetic beta- and alpha-cells, compared with the corresponding IR in control pancreas. Most noticeable was the eliciting of a markedly enhanced AC8-IR in GK rat beta- and alpha-cells, in contrast to a barely discernible AC8-IR in corresponding normal cells. In conclusion, AC expression exhibits a complex pattern in the endocrine pancreas, with specific differences between the normal and diabetic state.

Endocrine cell distribution and expression of tissue-associated antigens in human female paraurethral duct: possible clue to the origin of urethral diverticular cancer

BACKGROUND

To investigate (i) what determines the histologic differences seen among female urethral diverticular cancers and (ii) the possible embryologic origin of the female paraurethral duct, we performed a distribution analysis of endocrine cells and a comparative study of tissue-associated antigens in the female paraurethral duct.

METHODS

Six human female urethras were obtained from surgical and autopsy cases including two cases of urethral diverticular cancer (columnar/mucinous type adenocarcinoma). The urethral and paraurethral epithelia were examined histologically and immunohistochemically.

RESULTS

Immunoreactive endocrine cells predominated and carcinoembryonic antigen (CEA) was strongly expressed in the larger portion of the paraurethral duct close to the urethral lumen. Conversely, prostate-specific antigen and prostatic acid phosphatase were positive only in the smaller distal duct. In two cases of adenocarcinoma including endocrine cells, cancer cells were strongly positive for CEA.

CONCLUSIONS

This study suggests that the proximal and distal parts of the paraurethral duct have different histologic characteristics and that the pathologic differences seen among female diverticular cancers may result from their cancer-genesis from different parts of the paraurethral duct.

Gastrin stimulates the growth of gastric pit with less-differentiated features

Gastrin stimulates the growth of gastric mucosa by increasing mostly its glandular region but is not known to induce the growth of a pit region where its major constituent cells, gastric surface mucous (GSM) cells, turn over rapidly. To investigate the effect of gastrin on GSM cells, we generated hypergastrinemic mice by expressing a human gastrin transgene. We obtained a hypergastrinemic mouse line whose average serum gastrin level is 671 +/- 252 pg/ml (normal level <150 pg/ml). Gastrin-positive cells were found in the fundic mucosa. The gastric mucosa exhibited hypertrophic growth, which was characterized by an elongated pit with an active proliferative zone, but the glandular region containing parietal cells was normal or reduced in size. The GSM cells contained fewer mucous granules than those of control littermates and lost reactivity to the GSM cell-specific cholera toxin beta-subunit lectin. GSM cells along the foveolar region and many mucous neck cells became Alcian blue positive, suggesting the appearance of sialomucin in these cells. We suggest that gastrin stimulates the growth of the proliferative zone of gastric glands, which results in the elongation of the pit region whose GSM cells exhibit less-differentiated features.

The cadherin-catenin system: implications for growth and differentiation of endocrine tissues

Cell-cell adhesion, as mediated by the cadherin-catenin system, is a prerequisite for normal cell function and the preservation of tissue integrity. With recent progress in our understanding, beta-catenin as a component of a complex signal transduction pathway may serve as a common switch in central processes that regulate cellular differentiation and growth. The function of the cadherin-catenin system in cell adhesion as well as in intracellular signaling, appears to be subjected to multifactorial control by a variety of different mechanisms, and data on a hormonal control of these signaling pathways, even though scarce to date, suggest an important regulatory influence in many cellular systems. Loss of E-cadherin-catenin function was described in many tumors along with an increased invasiveness and a decreased prognosis of many carcinomas, including tumors of endocrine glands and their target systems, and a causal role of this loss-of-function in the multifactorial process of tumorigenesis was recently proven in genetic mouse models. Modification of E-caderin-catenin function in endocrine and nonendocrine tumors may involve germline and somatic gene mutations, epigenetic mechanisms such as gene silencing due to promotor-hypermethylation, and posttranscriptional events, likely to be involved in many endocrine tissues and their target organs. Such events may converge on nuclear activation of oncogenes such as c-myc by the beta-catenin/TCF4 complex. The expression and functional status of the components of the cadherin-catenin system may serve as prognostic markers for endocrine and nonendocrine tumors. The frequent involvement of functional dysregulation in many tumors raises hopes that better definition of the regulation of all components of the cadherin-catenin system and their response to extracellular modulators may eventually lead to new therapeutic approaches for these tumors and help to prevent, more specifically, growth, invasion, and metastasis of these carcinomas.

Immunohistochemical localization of chromogranin A in endocrine tissues and endocrine tumors of dogs

Chromogranin A is present in the secretory granules of endocrine cells and functions in hormone packaging, secretory granule stabilization, and regulation of hormone secretion. Immunohistochemical identification of chromogranin A can facilitate diagnosis of endocrine neoplasia. Normal and neoplastic canine tissues were stained immunohistochemically for chromogranin A. Staining of normal endocrine tissues demonstrated chromogranin A in chromaffin cells of the adrenal medulla, C cells of the thyroid gland, and pancreatic islets. The parathyroid chief cells and anterior pituitary stained lightly positive for chromogranin A. Pheochromocytomas (7/7), chemodectomas (5/7), islet cell carcinomas (2/6), pituitary adenomas (4/6), parathyroid adenomas (3/7), and a C-cell carcinoma (1/1) stained positive for chromogranin A. The data indicate that chromogranin A is widely distributed in canine endocrine tissues, and immunohistochemical staining of chromogranin A can be used to confirm the presence of secretory granules in endocrine tumors.

Methyl tertiary butyl ether-induced endocrine alterations in mice are not mediated through the estrogen receptor

Chronic exposure to methyl tertiary butyl ether (MTBE) altered the rodent tumor incidence of endocrine-sensitive tissues and decreased the incidence of estrogen-dependent uterine cystic hyperplasia in mice. To test the hypothesis that changes in the incidence of tumors in female B6C3F1 mice after MTBE exposure are secondary to endocrine alterations, we exposed female mice to the carcinogenic dose of MTBE vapor (8000 ppm) for 3 or 21 days or 4 or 8 months under conditions similar to a previous 2-year bioassay. MTBE exposure significantly decreased body weight gain and ovary and pituitary weight at 4 and 8 months and uterine weight at all time points. After 8 months of exposure, MTBE significantly increased the length of the estrous cycle by increasing the mean number of days in both the estrus and the nonestrus stages. Histological evaluation of H&E-stained tissues showed a decrease in the number of uterine glands after subchronic MTBE exposure. DNA synthesis, as measured by the incorporation of 5-bromo-2'-deoxyuridine (BrdU), was decreased in uterine glandular and luminal epithelial cells after MTBE exposure for 3 or 21 days or 4 or 8 months. MTBE exposure decreased the number of epithelial layers in the cervix and vagina at all time points. DNA synthesis was decreased in cervical and vaginal epithelium after 21 days of MTBE. Decreased zona reticularis of adrenal glands was found after 4 and 8 months of MTBE exposure without changes in BrdU incorporation. MTBE did not competitively bind to estrogen receptor. MTBE exposure did not alter serum estrogen levels or alter the location or intensity of estrogen receptor immunoreactivity in the uterus, cervix, and vagina. These data indicate that while MTBE exposure causes multiple endocrine-related tissue and cellular responses, these effects are not mediated through the estrogen receptor.

Endocrine cells in hepatobiliary cystadenomas and cystadenocarcinomas

We investigated the distribution of endocrine cells in hepatobiliary cystadenoma (n = 5, two associated with mesenchymal stroma) and cystadenocarcinoma (n = 3) immunohistochemically. In normal livers (n = 20) and livers affected by hepatolithiasis (n = 15) used as controls, endocrine cells revealed by chromogranin immunostaining were located exclusively in normal or proliferating intrahepatic peribiliary glands. In the eight cases of hepatobiliary cystadenoma and cystadenocarcinoma, endocrine cells were present in four cases (50%) (1 cystadenoma, 1 cystadenoma with mesenchymal stroma, and 2 cystadenocarcinomas). Endocrine cells tended to be located beneath and among the columnar epithelial cells. Intrahepatic peribiliary glands were located in the vicinity of cystadenoma or cystadenocarcinoma in six (75%) of the eight cases, and they frequently showed cystic dilatation and contained endocrine cells. Intrahepatic peribiliary glands were located in the vicinity of the endocrine cells in all cystadenomas and cystadenocarcinomas that were positive for endocrine cells. These data show that about 50% of hepatobiliary cystadenomas and cystadenocarcinomas contain endocrine cells and suggest that hepatobiliary cystadenoma and cystadenocarcinoma may originate from intrahepatic peribiliary glands.

Tissue and cell-type specific expression of the tuberous sclerosis gene, TSC2, in human tissues

TSC2 is a gene on chromosome 16p13.3 associated with the autosomal dominant neurocutaneous disorder, tuberous sclerosis complex (TSC). By using a partial nucleotide sequence from the cloned TSC2 and polymerase chain reaction methodology, we constructed a digoxigenin-labeled complementary DNA probe to examine TSC2 gene expression in autopsy- or biopsy-derived human tissues by in situ hybridization. TSC2 messenger RNA was widely expressed in various cell types throughout the body, including epithelia, lymphocytes, and cells with endocrine functions, e.g., adrenal cortex and anterior pituitary. It was prominently and selectively (within the central nervous system) expressed in pyramidal cells of the cerebral cortex and other motor neurons, e.g., in spinal cord and brainstem nuclei. Visceral TSC2 expression was comparable in autopsy tissues from patients with and without TSC; TSC2 messenger RNA expression was most prominent in cells with a rapid mitotic rate and turnover, e.g., epithelia and lymphocytes, with central nervous system pyramidal cells and other neurons being an obvious exception, and/or in cells with important secretory/transport functions. This widespread expression of the TSC2 gene supports the view that it encodes a protein vital to cell growth and metabolism or one that functions as a tumor/growth suppressor.

Endocrine cells in tumour-bearing lungs

BACKGROUND

When hormones are detected in the serum of patients with bronchial carcinoma they are generally considered to originate from the tumour, but this may be not the only explanation. Pulmonary endocrine cells proliferate in lungs affected by non-neoplastic disease and their products are often demonstrable in the serum. The aim of this study was to examine the pulmonary endocrine systems of a series of tumour-bearing lungs to see whether any changes in them could possibly account for raised levels of pulmonary peptides in the blood.

METHODS

The morphology, number, distribution, and content of pulmonary endocrine cells in 30 pairs of tumour-bearing lungs from patients coming to necropsy with bronchial carcinoma were examined. These features were related to the pathology of the tumour and to other pathological changes present in the lungs, and compared with pulmonary endocrine cells in 10 pairs of control lungs from patients without pulmonary disease.

RESULTS

Increased numbers of endocrine cells, often in the form of large abnormal aggregates, were present in 17 pairs of tumour-bearing lungs where they were associated not with the tumour but with non-tumoral pathology, especially inflammation and changes associated with cardiac failure. Appropriate and inappropriate peptides were identified within them.

CONCLUSION

The possibility is raised that, in some subjects with bronchial carcinoma who have raised serum hormone levels, the source of these substances might be the endocrine cells in the diseased lung around the tumour.

Pattern of gastric endocrine cells in microcarcinoidosis--an immunohistochemical study of 14 gastric biopsies

A total of 14 gastric biopsy specimens from patients with microcarcinoidosis were analysed by immunohistochemical methods to evaluate the pattern of endocrine cell hyperplasia and dysplasia. All the patients had type A gastritis (autoimmune gastritis). Nonantral proliferations of gastric endocrine cells were classified according to Solcia et al. All 14 cases had hyperplasia and 13 (92.9%) of them, dysplasia of gastric endocrine cells; 9 (64.3%) of the 14 were found to have showed a coexisting invasive gastric carcinoid at the time of diagnosis of microcarcinoidosis. The patients with invasive carcinoids had higher degrees and more complex forms of endocrine dysplasia (precarcinoid lesions). The average size of the foci of the microcarcinoidosis in gastric biopsies was 0.14 +/- 0.09 cm in the patients without invasive carcinoid, as against to 0.5 +/- 0.24 cm in the group of patients with associated invasive carcinoid. Microcarcinoid gastric biopsies about 0.5 cm in size, are suggestive of adjacent invasive carcinoid. However, even frankly invasive ECL carcinoids seem to be clinically less dangerous than was thought until recently.

Neoplastic and non-neoplastic lesions in the mammary gland, endocrine and genital organs in aging male and female Sprague-Dawley rats

The non-neoplastic and neoplastic lesions in adrenals, thyroids, pituitary, uterus, ovaries, testes and mammary gland of senile untreated Sprague-Dawley rats were evaluated. The correlation between the neoplastic and non-neoplastic lesions in the pituitary gland and those in the target organs was made. The pituitary gland of the senile Sprague-Dawley rats had focal or diffuse hyperplasia and/or hypertrophy of PRL, STH, and ACTH cells. Approximately 47% of the males and 62% of the females had pituitary adenomas. Multiple adenomas in the same pituitary were noted in 7% of the males and in 11% of the females. Although many adenomas contained pleomorphic foci and quite a number of mitotic figures and were locally invasive, no evidence of distant metastases was discovered; therefore carcinoma was not diagnosed in the present material. The adenomas observed were divided into different types on the basis of the cytological characteristics of the cellular elements. Single cell-type adenomas such as PRL-, ACTH-, STH-, TSH-, immature- gonadotrophin-cell adenomas, and mixed cell (more than one cell type) adenomas were diagnosed. The adenomas containing PRL cells were the predominant type of neoplasms and they represented 30% and 34% of the total pituitary neoplastic lesions observed in males and females, respectively. The cytological changes in the hypophyseal cell types in senile Sprague-Dawley rats were usually accompanied by spontaneous non-neoplastic and neoplastic lesions in adrenals, thyroids, testes, ovaries, and mammary gland. The possible role of the hypophyseal hormones in the induction of the non-neoplastic and neoplastic lesions in the target organs is discussed. The combination of the spontaneous endocrine tumors could be associated both with aging and with genetic background of the animals. In addition, this polyglandular proliferative lesion in Sprague-Dawley rats might represent a potential model of mixed MEN syndrome.

Atrio-ventricular nodal tumor associated with polyendocrine anomalies

We report the clinical and autopsy findings of a young female suffering of complete heart block since the age of 11 and who suddenly died at the age of 32 because of a polycystic atrio-ventricular node tumor. In association with this tumor, we observed a hyperplasia of the islets of Langherans, a true thymic hyperplasia, bilateral multicystic ovaries, adrenal tissue heterotopia and clear cell adenomatosis in the right kidney. We suggest that the polycystic atrio-ventricular node tumor may be part of a complex syndrome with endocrine disorders and heterotopias.

Single jejunoileal and right colonic carcinoids as midgut tumors. A study collating immunophenotypes and histogenesis

The jejunoileum and the right colon, both of which are located in the midgut, have some histologic similarities such as the presence of Paneth cells and intraepithelial endocrine cells (IEECs). Since gastrointestinal (GI) carcinoids arise from the same stem cells as GI endocrine cells, the question was whether or not there might also be similarities in the histogenesis of jejunoileal carcinoids (JICs) and right colonic carcinoids (RCCs). Ten single JICs and 3 RCCs together with their respective controls were stained using various neurohormonal immunoreagents. Our results showed that neither the JICs nor the RCCs appeared to arise from a background of diffuse IEEC hyperplasia. Furthermore, in the jejunoileum, serotonergic progenitor cells appear to have a proclivity for neoplastic transformation, as do cells of the pancreatic polypeptide and glucagon lineage in the right colon.

The incidence of chromogranin A defined endocrine cells decreases with tumour progression in gastric adenocarcinoma

The immunohistochemical expression of chromogranin A (CGA) was investigated in 60 normal mucosas, 95 primary tumours and 38 metastatic lymph nodes. CGA was expressed in 100% of the normal mucosas, 61% of the primary tumours that were restricted within the submucosal layer, 21% of the primary tumours that invaded beyond the submucosal layer, and 11% of the metastatic lymph nodes. The 5-year survival rates in patients with negative and positive expression of CGA in primary tumours were 60.4% and 74.6%, respectively. These results indicate that endocrine cells occupy an integral part of gastric adenocarcinoma with regard to tumour progression.

[Analysis of stomach cancer according to data of the autopsy room at the I.M. Sechenov Moscow Medical Academy from 1941-1994]

Analysis of the above material showed the association of the unfavorable clinico-morphological indices and poor prognosis with the periods of a socioeconomic instability, and the participation of a pathological hormonal background in the development of some variants of undifferentiated carcinoma of the stomach.

Langerhans cell histiocytosis

The first major stride toward understanding LCH was taken when ultrastructural studies identified the proliferating cells as part of the Langerhans (dendritic) cell system. Another step forward was the definition of the morphologic, immunohistochemical, and clinical criteria needed for the diagnosis of LCH. Meanwhile, modern imaging studies have disclosed lesions that were not previously visible, especially those in the brain and the pituitary gland. These advantages have had a major impact on clinical management by making it possible to compare data from different institutions and to centralize coherent clinical and therapeutic data. Moreover, the agreement concerning diagnostic criteria provides a solid foundation for current clinical trials and for laboratory research regarding the possible roles of the immune system, clonality, and cytokines in the etiology of LCH.

Chemical mixtures exposure and children's health

Studies to examine the health of the children with compromised immune and endocrine systems living in different air polluted regions by oil waste were undertaken. A dose-dependent effects of the anthropogenic pollution on the functional immunocompetent cells activity, mainly T-suppressors was observed as well as stimulation of immunoglobulins synthesis and reduction of phagocytic activity of neutrophils. Disconnection of immunoglobulins synthesis with production of high specifity antibodies, antiviral in particular, was registered. Correlation changes between indices of hormonal activity and humoral specific defence leading to an increase in the role of peripheral hormones with immune inhibitory effect were revealed. The informative value of studied indices as environmental pollution bioindicators was considered. They will stimulate further investigations in biomonitoring and its introduction into practice of ecological expertise of dwelling agglomerations.

Florid deep glands of the uterine cervix. Another mimic of adenoma malignum

Two cases of florid deep glands of the uterine cervix, a lesion which mimics adenoma malignum are reported. One case was misdiagnosed as adenoma malignum, and the patient was treated with adjuvant radiotherapy. In contrast to the majority of cases of adenoma malignum in which there is preoperative evidence of a cervical abnormality, the lesion described in both cases was an incidental microscopic finding in hysterectomy specimens. The architectural pattern in both these cases was strikingly similar, showing diffusely scattered endocervical glands within the endocervical stroma extending to the outer third of the cervical wall. However, the variability in size and shape of the glands, which were typically round to oval, was less than observed in adenoma malignum. Additionally, there was no cytologic atypia, which is observed focally in most cases of deeply invasive adenoma malignum. The lack of a desmoplastic stromal reaction, vascular and perineural invasion also may help distinguish florid deep glands from adenoma malignum. Finally, in both cases of florid deep glands, there was no cytoplasmic immunoreactivity for carcinoembryonic antigen, which is in contrast to what is seen in adenoma malignum.

Pulmonary endocrine cells in plexogenic pulmonary arteriopathy associated with cirrhosis

A clear association has been described between numbers of pulmonary endocrine cells and the migration and/or proliferation of myofibroblasts which is thought to underlie the vascular changes seen in plexogenic pulmonary arteriopathy due to cardiac shunts and primary pulmonary hypertension. In contrast, the pulmonary endocrine system in a subject with florid pulmonary plexogenic arteriopathy associated with cirrhosis was entirely normal, suggesting possible differences in its pathogenesis.