Comparison of the clinicopathological features of pancreatic solid pseudopapillary neoplasms between males and females: gender does matter.

BACKGROUND: Solid pseudopapillary neoplasms (SPN) of the pancreas are a rare and low-grade malignant entity with a female predominance. However, it also occurs in males, but the rarity and lack of concern makes its clinicopathological features unclarified. METHODS: The morphological, immunohistochemical, prognostic features and CTNNB1 exon 3 mutation status of SPN were compared semi-quantitively between 9 male and 21 female patients. RESULTS: SPN in males grew in a distinctive solid pattern, with abundant fibrotic stroma and clear cells. Collagen tended to be the main component of tumor stroma in males, while hyaluronan composed a considerable proportion in females. A much stronger expression of androgen receptor (AR) was found in males, and CD56 and/or synaptophysin (Syn) was expressed frequently in both genders. All patients survived. One male patient had post-operational liver nodules and accepted interventional therapy without biopsy. Mutations of CTNNB1 exon 3 were observed in all cases, distributed at codon 32, 33 and 37 in both genders, as well as 34, 41 and 62 in females. CONCLUSION: SPN in males presented with significantly different morphological features from that in females, which might be helpful in differential diagnosis, especially when with extensive positivity for CD56 and/or Syn. The stronger expression of AR in males might be a clue to explore the underlying mechanism of the gender difference.

Neuropeptide S receptor 1 (NPSR1) activates cancer-related pathways and is widely expressed in neuroendocrine tumors.

Neuroendocrine tumors (NETs) arise from disseminated neuroendocrine cells and express general and specific neuroendocrine markers. Neuropeptide S receptor 1 (NPSR1) is expressed in neuroendocrine cells and its ligand neuropeptide S (NPS) affects cell proliferation. Our aim was to study whether NPS/NPSR1 could be used as a biomarker for neuroendocrine neoplasms and to identify the gene pathways affected by NPS/NPSR1. We collected a cohort of NETs comprised of 91 samples from endocrine glands, digestive tract, skin, and lung. Tumor type was validated by immunostaining of chromogranin-A and synaptophysin expression and tumor grade was analyzed by Ki-67 proliferation index. NPS and NPSR1 expression was quantified by immunohistochemistry using polyclonal antibodies against NPS and monoclonal antibodies against the amino-terminus and carboxy-terminus of NPSR1 isoform A (NPSR1-A). The effects of NPS on downstream signaling were studied in a human SH-SY5Y neuroblastoma cell line which overexpresses NPSR1-A and is of neuroendocrine origin. NPSR1 and NPS were expressed in most NET tissues, with the exception of adrenal pheochromocytomas in which NPS/NPSR1 immunoreactivity was very low. Transcriptome analysis of NPSR1-A overexpressing cells revealed that mitogen-activated protein kinase (MAPK) pathways, circadian activity, focal adhesion, transforming growth factor beta, and cytokine-cytokine interactions were the most altered gene pathways after NPS stimulation. Our results show that NETs are a source of NPS and NPSR1, and that NPS affects cancer-related pathways.

Vascular endothelial growth factor (VEGF) - part 2: in endocrinology and oncology.

Endocrine glands are well vascularised and the structure of their vessels facilitates the exchange of various substances, including hormones. These glands are a frequent experimental model in research on VEGF and angiogenesis. VEGF participates in the pathogenesis of diabetes. Diabetic nephropathy is in essence a microvascular disease that develops as a result of a confluence of haemodynamic and metabolic perturbations. Diabetic retinopathy is the commonest microvascular complication of diabetes mellitus and is the leading cause of blindness. In diabetic retinopathy, ischaemic states, and hence tissue hypoxia and angiogenesis, take place. The participation of angiogenesis and VEGF in the pathogenesis of neoplastic disease has been described in many papers. VEGF protein and mRNA have been found in cancers of the thyroid, bronchus, lungs, oesophagus, stomach, colon, liver, breast, ovary, uterus, kidney, and urinary bladder, and in malignant tumours of the brain and bone. There have been many reports of the connections between the degree of VEGF expression and tumour aggression and prognosis in patients. Richly vascularised are GEP NET. In neuroendocrine tumours, strong expression of VEGF, Flt-1 and KDR in relation to the unchanged surrounding tissues has been demonstrated. Depending on the disease entity or the degree of its severity, attempts to apply angiogenic and antiangiogenic therapy have being made. Antiangiogenic therapy (usually regarded as a form of cancer therapy) is based on: 1. inhibitory effects of proangiogenic ligands and their receptors; 2. stimulation or delivery of angiogenesis inhibitors; and 3. direct destruction of neoplastic tumour vasculature.

Tumores endocrinos o apudomas pancreáticos / Pancreatic endocrine tumors or apudomas

Introducción y objetivo: los tumores endocrinos pancreáticos (TEP) son difíciles de diagnosticar. Su localización exacta mediante métodos de imagen tiene el propósito de lograr una curación definitiva. El objetivo de este trabajo retrospectivo fue revisar una serie institucional privada de TEP. Pacientes y métodos: se revisaron las historias clínicas de 19 pacientes con TEP, 4 casos con NEM-1, observados durante 17 años (1994-2010). Se creó una base de datos con diez parámetros: edad y sexo, síntomas, métodos diagnósticos de imagen, tamaño y situación en el páncreas, metástasis, cirugía, complicaciones, tratamientos complementarios, diagnóstico definitivo, supervivencia o éxitus. Resultados: en total se analizaron 19 casos. La edad media de presentación fue 51 años (intervalo: 26-67 años) (14 varones y 5 mujeres), con un tamaño del tumor de 5 a 80 mm (X: 20 mm). El 37% (7/19) tenían metástasis. En la mayoría se practicaron los siguientes métodos de imagen: ecografía, TAC y RM. La PAAF del tumor primitivo se practicó en 4 casos. No funcionantes: 7 casos (37%), insulinomas: 2 casos (1 con posible NEM), SZE por gastrinomas: 5 (3 con NEM-1), glucagonoma: 2 casos, 2 somatostatinomas, carcinoide: 1 caso con síndrome carcinoide-like. La mayoría de los enfermos fueron intervenidos quirúrgicamente 14/19 (73%). En cuatro (4/14: 28%) pacientes hubo complicaciones postoperatorias después de pancreatectomías: páncreas, seudoquiste y colecciones abdominales. Algunos casos fueron tratados con quimioterapia (4), somatostatina (3) e interferón (2) antes o después de la cirugía. La mediana de seguimiento fue de 48 meses. La supervivencia actuarial en el momento del estudio fue del 73,6% (14/19). Conclusiones: la edad fue similar a lo descrito en la literatura. El sexo predominante fue el masculino. La mayoría fueron no funcionantes (37%). La mayoría fueron intervenidos quirúrgicamente (73%), con escasa morbilidad (28%) y con una supervivencia actuarial en el momento de cerrar el estudio del 73,6%(AU)

Introduction and objective: pancreatic endocrine tumors (PET) are difficult to diagnose. Their accurate localization using imaging techniques is intended to provide a definite cure. The goal of this retrospective study was to review a PET series from a private institution. Patients and methods: the medical records of 19 patients with PETs were reviewed, including 4 cases of MEN-1, for a period of 17 years (1994-2010). A database was set up with ten parameters: age, sex, symptoms, imaging techniques, size and location in the pancreas, metastasis, surgery, complications, adjuvant therapies, definite diagnosis, and survival or death. Results: a total of 19 cases were analyzed. Mean age at presentation was 51 years (range: 26-67 y) (14 males, 5 females), and tumor size was 5 to 80 mm (X: 20 mm). Metastatic disease was present in 37% (7/19). Most underwent the following imaging techniques: ultrasounds, computed tomography (CT) and magnetic resonance imaging (MRI). Fine needle aspiration punction (FNA) was performed for the primary tumor in 4 cases. Nonfunctioning: 7 cases (37%), insulinoma: 2 cases [1 with possible multiple endocrine neoplasia (MEN)], Zollinger-Ellison syndrome (ZES) from gastrinoma: 5 (3 with MEN-1), glucagonoma: 2 cases, 2 somatostatinomas; carcinoid: 1 case with carcinoide-like syndrome. Most patients were operated upon: 14/19 (73%). Four (4/14: 28%) has postoperative complications following pancreatectomy: pancreatitis, pseudocyst, and abdominal collections. Some patients received chemotherapy (4), somatostatin (3) and interferon (2) before or after surgery. Median follow-up was 48 months. Actuarial survival during the study was 73.6% (14/19). Conclusions: age was similar to that described in the literature. Males were predominant. Most cases were non-functioning (37%). Most patients underwent surgery (73%) with little morbidity (28%) and an actuarial survival of 73.6% at the time of the study(AU)

[Outstanding problems of normal and pathological morphology of the diffuse endocrine system].

The diffuse endocrine system (DES)--a mosaic-cellular endoepithelial gland--is the biggest part of the human endocrine system. Scientists used to consider cells of DES as neuroectodermal. According to modem data cells of DES are different cytogenetic types because they develop from the different embryonic blastophyllum. So that any hormone-active tumors originated from DES of the digestive, respiratory and urogenital system shouldn't be considered as neuroendocrinal tumors. The basic problems of DES morphology and pathology are the creation of scientifically substantiated histogenetic classification of DES tumors.

Clinicopathological evaluation of duodenal well-differentiated endocrine tumors.

AIM: To assess the clinicopathological characteristics of duodenal well-differentiated endocrine tumors. METHODS: We examined clinicopathological characteristics in 11 consecutive patients with duodenal well-differentiated endocrine tumors treated by endoscopic therapy or surgery in our hospital from 1992 through 2007. Patients with well-differentiated endocrine tumors of the papilla of Vater or with gastrinoma were excluded. RESULTS: Three patients received endoscopic treatment, and 8 underwent surgery. In patients who received endoscopic treatment, the tumor diameter was less than 1.0 cm, with no histopathological evidence of lymphovascular invasion or invasion of the muscularis. There were no complications such as late bleeding or perforation after treatment. Among 8 patients with tumors less than 1.0 cm in diameter, 3 underwent partial resection, and 2 underwent radical surgery. Three patients had lymphovascular invasion, 1 had invasion of the muscularis, and 1 had proximal lymph node metastasis. Among 3 patients with tumors 1.0 cm or more in diameter, 1 underwent partial resection, and 2 underwent radical surgery. One patient had lymphovascular invasion, with no lymph node metastasis. After treatment, all patients are alive and have remained free of metastasis and recurrence. CONCLUSION: Duodenal well-differentiated endocrine tumors less than 1.0 cm in diameter have a risk of lymphovascular invasion, invasion of the muscularis, and lymph node metastasis, irrespective of procedural problems.

The significance of new somatostatin analogs as therapeutic agents.

The effects of somatostatin, or somatotropin release-inhibiting factor (SRIF), and SRIF analogs in human diseases have been widely investigated to potentially expand the therapeutic applications of commercially available and newly designed compounds belonging to this class of agents. Several preclinical studies and clinical trials have demonstrated the antiproliferative and antisecretory effects of SRIF and its analogs. This review discusses results from studies investigating the secretory activity and cell viability of SRIF analogs, and the potential of new therapeutic applications of these drugs in endocrine diseases and, in particular, as a treatment for endocrine neoplasia.

The tumor stem cell concept-implications for endocrine tumors?

The cancer stem cell hypothesis has recently evolved from an increasing body of evidence suggesting that in some cancers a small population of tumor cells with stem cell-like properties represents a critical component that dictates the malignant behavior of a given tumor. These observations challenge classical cancer biology and its theory, that tumor growth is mainly based on genomic alterations followed by modulation of cell cycle pathways, which finally result in uncontrolled clonal proliferation. Over the last few years, much progress in the field of tumor stem cells has been achieved in non-endocrine malignancies. In this review, we summarize the existing evidence regarding the tumor stem cell concept for tumor pathophysiology in general and highlight current models that have the potential to further impact research on endocrine tumors.

Menin regulates endocrine diseases by controlling histone modification and gene transcription.

Multiple endocrine neoplasia type 1 (MEN1), a human familial tumor syndrome, results from mutations in the Men1 gene. Although much progress has been made in demonstrating the definitive role for menin in suppressing tumorigenesis in endocrine organs, the molecular pathways responsible for menin action in normal tissues and tumors remain poorly defined. Here, we review the recent progress on the molecular functions of menin in controlling cell proliferation, apoptosis, and DNA repair. The majority of these functions are largely executed by menin-mediated influencing of histone modifications and chromatin structure. These findings lead to a new model of understanding menin's tumor-suppressing function, providing insights into understanding of how menin regulates cell proliferation and the development of endocrine tumors. The new knowledge could also be translated into new strategies to improve therapeutic interventions against MEN1 and other endocrine diseases including diabetes.

Endocannabinoids in endocrine and related tumours.

The 'endocannabinoid system', comprising the cannabinoid CB1 and CB2 receptors, their endogenous ligands, endocannabinoids and the enzymes that regulate their biosynthesis and degradation, has drawn a great deal of scientist attention during the last two decades. The endocannabinoid system is involved in a broad range of functions and in a growing number of physiopathological conditions. Indeed, recent evidence indicates that endocannabinoids influence the intracellular events controlling the proliferation of numerous types of endocrine and related cancer cells, thereby leading to both in vitro and in vivo antitumour effects. In particular, they are able to inhibit cell growth, invasion and metastasis of thyroid, breast and prostate tumours. The chief events of endocannabinoids in cancer cell proliferation are reported highlighting the correspondent signalling involved in tumour processes: regulation of adenylyl cyclase, cyclic AMP-protein kinase-A pathway and MEK-extracellular signal-regulated kinase signalling cascade.

RET signaling in endocrine tumors: delving deeper into molecular mechanisms.

The rearranged during transfection (RET) proto-oncogene encodes a receptor tyrosine kinase that is implicated in the development of endocrine tumors of the thyroid and adrenal glands. In humans, activating RET mutations are found in the inherited cancer syndrome multiple endocrine neoplasia 2 and in sporadic medullary and papillary thyroid carcinomas. The specific type and location of RET mutations are strongly correlated with the disease phenotype and have both diagnostic and prognostic value. Recent advances in the molecular characterization of the RET receptor and its mutants have begun to define the mechanisms underlying the transforming ability of the different RET mutant forms. This information has revealed key functional features of these mutant proteins that distinguish the different clinically recognized mutations and provide clues as to the functional origins of the phenotypes associated with specific RET mutations. The elucidation of molecular mechanisms involved in RET-mediated transformation is a key step in the development of much needed therapeutics that target RET's oncogenic properties. Recent advances have begun to provide a deeper understanding of the receptor's function, and dysfunction, in human tumors that may guide this process.

Role of neuropeptide Y and its receptors in the progression of endocrine-related cancer.

The neuropeptide Y (NPY) family of peptides, in addition to its many physiological actions, has also been involved in the modulation of tumor progression, with specific reference to endocrine-related cancers such as neuroendocrine tumors, breast and prostate cancers. These have been found either to express NPY receptors, or to secrete NPY-related peptides, or both. The study of the role of the NPY family of peptides in the biology of endocrine-related tumors, specifically concerning cell proliferation, angiogenesis, invasion and metastatization, may help to clarify some aspects of tumor pathophysiology, as well as to indicate novel diagnostic markers and therapeutical approaches.

Quantity of AgNORs in gastric endocrine carcinoid tumours as a potential prognostic tool.

In order to assess if the quantity of silver-stained nucleolar organizer region (AgNOR) proteins represents a prognostic tool in gastric carcinoids, a standardised AgNOR analysis was performed on 24 samples collected from the pathology archives of the Universities of Messina and Parma; the samples were taken at surgery from 11 males and 13 females (mean age 55 yrs, age range 28-77 yrs); 13 cases were defined as Type I, 1 case as Type II and 10 cases as Type III; 16 cases showed a diameter <1 cm, 8 >1 cm. Only 6 tumours were deeply invasive, breaking through the muscularis propria or the subserosa. The proliferative status of carcinoids performed by Ki67 protein antibodies was available in 20/24 cases. The quantification of AgNORs was performed according to the guidelines of the Committee on AgNOR Quantification and the mean area (microm2) of AgNORs per nucleus (NORA) was determined by means of image analyser and specific software programs. The relationship between NORA values and Ki67 data was investigated by Spearman correlation test. The mean NORA value of all 24 gastric carcinoids was 1.279 microm2 (SD 0.404); values ranged from 0.734 to 2.142 microm2. A significantly higher (p < 0.001) mean NORA value (1.736 microm2; SD 0.283) was found in tumours larger than 1 cm, in comparison to the smaller neoplasms (1.051 microm2; SD 0.214); moreover, cases showing deep wall invasion exhibited a mean NORA value of 1.765 microm2 (SD 0.276), significantly higher (p < 0.001) than those with superficial growth (1.118 microm2; SD 0.296). Finally, a similar highly significant difference was seen between type III carcinoids (1.615 microm2; SD 0.375) and type I-II (1.040 microm2; SD 0.208). A linear relationship between Ki67 and corresponding NORA values was obtained by the Spearman correlation test (p = 0.001). No other significant correlations were found between mean NORA values and other clinico-pathological parameters. The AgNOR method seems to be an additional tool potentially able to predict the prognosis of this kind of endocrine tumour, facilitating the identification of fast-growing tumours and being able to directly correlate with the size, deep invasion of gastric wall and tumour type, generally considered as the best prognostic indicators.

The molecular pathogenetic role of cell adhesion in endocrine neoplasia.

It is becoming increasingly evident that cell adhesion is an important determinant of organised growth and the maintenance of architectural integrity. Indeed, reduced adhesiveness between cells and with the extracellular matrix is a hallmark of neoplastic growth. In neuroendocrine tissues, neural cell adhesion molecule is implicated in modulating cell growth, migration, and differentiation. This review will focus on the molecular pathways involving key growth factor receptors that govern normal adhesive forces. The extent to which disruption of these adhesive forces contributes to the tumorigenic process in neuroendocrine tissues will be highlighted. Validation of the functional relevance of these adhesive pathways will be discussed in light of targeted pharmacotherapeutic studies that are unmasking novel approaches to the treatment of neuroendocrine tumours.

Obesity: an endocrine tumor?

Obesity is one of the most common disorders in clinical practice. The prevalance of obesity has increased by more than 60% since 1990. Adipose tissue acts as an endocrine organ secreting many factors into the blood, known as adipokines, including leptin, adipsin, acylation-stimulating protein, adiponectin, etc. This article examines the hypothesis that obesity may be evaluated as an endocrine tumor, regarding its genetic basis, hyperplasia and hypertrophy of adipocytes, neovascularisation within the adipose tissue associated with growth, and beneficisal metabolic effects of surgical removal of excess adipose tissue by liposuction. Assuming obesity as an endocrine tumor may bring out new treatment modalities. Liposuction as "cytoreductive surgery", antiangiogenic teraphy or anti-neoplastic drugs may be important components of obesity treatment in future.

Carcinogenesis of gastric endocrine cell carcinoma: analysis of histopathology and p53 gene alteration.

BACKGROUND: Endocrine cell carcinoma of the stomach is characterized by endocrine differentiation and aggressive biological behavior, and is frequently accompanied by an adenocarcinoma component. Because the carcinogenic parthway and genetic alterations remain unclear, we investigated the histogenesis of the tumor by histopathological and p53 gene analysis. METHODS: The materials were 68 gastric endocrine cell carcinomas and 30 carcinoid tumors, which were resected from 93 Japanese patients for histopathological and immunohistochemical investigation. We also analyzed the concordance of p53 mutational status between the associated adenocarcinoma and endocrine cell carcinoma components, using microdissection and direct sequencing techniques. RESULTS: An adenocarcinoma component was associated with 70.6% (48/68) of endocrine cell carcinomas, of which 42 (87.5%) were of well- to moderately differentiated type, while 36 of these 42 (85.7%) demonstrated histological continuity with the endocrine cell carcinoma components. Overexpression of p53 protein was observed in 58.8% (20/34) of cases. Common p53 mutational status between the two components was revealed in 73.3% (11/15) of cases analyzed. In contrast, carcinoid tumors did not exhibit p53 protein overexpression (0/15) or gene mutation (0/5). CONCLUSIONS: These data suggest that gastric endocrine cell carcinomas predominantly arise from endocrine precursor cell clones occurring in preceding adenocarcinoma components (particularly the differentiated type), transforming into endocrine cell carcinoma during rapid clonal expansion under the influence of p53 gene alteration. Endocrine cell carcinoma of the stomach is characterized by endocrine differentiation and aggressive biological behavior, and is frequently accompanied by an adenocarcinoma component. Because the carcinogenic pathway and genetic alterations remain unclear, we investigated the histogenesis of this tumor by histopathological and p53 gene analysis.

Role of the PKA-regulated transcription factor CREB in development and tumorigenesis of endocrine tissues.

The cAMP pathway plays a major role in the development of endocrine tissues and various molecular defects of key components of this pathway (G protein, receptors, PKA, etc.) have been observed in endocrine tumors. The ubiquitous transcription factor CREB (cAMP-response element binding protein) binds to the cAMP response element (CRE) and stimulates transcription after phosphorylation on Ser(133) by PKA. The CREB family of transcription factors contains three members: CREB, CREM, and ATF-1. Targeted expression of dominant-negative mutants of CREB in transgenic mice leads to somatotrophs or thyroid hypoplasia. GH-secreting adenomas are benign secreting tumors expressing an activated mutant G alpha s protein (Gsp) in about 40% of cases. In GH-secreting adenomas CREB is always expressed and often highly phosphorylated. The CREM isoform ICER is stimulated by cAMP, and its expression is increased in Gsp-harboring tumors. After transfection in pituitary somatotroph cells, activating mutations of Gs protein (Gsp) and overexpression of wild-type G alpha S stimulate transcription of various CRE-containing promoters via CREB in a Ser(133)-specific-dependent manner. Activation of the cAMP pathway by ACTH is required for adrenal cortex (AdCx) maintenance and steroidogenesis. CREB is expressed in normal AdCx. Alterations of CRE binding proteins with loss of CREB expression and compensatory overexpression of CREMtau is observed in the human adrenocortical cancer cell line H295R. Similar alterations are found at the protein level in human malignant adrenocortical tumors. In conclusion, the CREB family of transcription factors plays an important role in the development, differentiation, and proliferation of endocrine tissues. Various alterations of the CREB family of transcription factors can be observed in endocrine tumors.