Vitamin D receptor and progesterone receptor protein and gene expression in papillary thyroid carcinomas: associations with histological features

PURPOSE

Vitamin D receptor (VDR) and progesterone receptor (PR) expression has been described in papillary thyroid carcinoma (PTC) but data regarding association with tumor histological characteristics and localization of the protein expression are scarce.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded specimens from 45 patients with PTC (cases) were retrieved and tumor histological data were recorded. We analyzed gene and protein expression of VDR and PR and gene expression of vitamin D-inactivating 24-hyroxylase (CYP24A1) and the activating 1-alpha-hydroxylase (CYP27B1) enzymes in follicular cancer cells and the adjacent non-neoplastic thyroid tissue (NNTT).

RESULTS

VDR mRNA and protein expression was higher in PTC compared with NNTT (p < 0.05). The protein was globally localized in the cytoplasm and cell membranes of the neoplastic cells in all cases, with differences in intensity. Cytoplasmic positivity was stronger in the majority of cases. Membranous positivity was also evident in cases, whereas in NNTT was generally weak and in a low percentage of the cells. Expression of CYP 24A1, but not CYP27B1, was increased in approximately all PTC specimens and was associated with lymph node metastasis and extrathyroidal extension. PR mRNA was increased in 34% and protein expression was present in 57% of cases, and none of NNTT. PR, but not VDR, mRNA expression was significantly associated with the tumor size (r = 0.645, p = 0.007).

CONCLUSIONS

We provide evidence for the expression pattern of VDR, PR and CYP24A1 in the progression of PTC. Rapid anti-tumor responses of vitamin D in PTC may be blocked due to inactivation of local vitamin D metabolism.

Serum Fcεrii Receptor (SCD23) as an Evaluating Factor for Grass Pollen Immunotherapy

CD23 is a protein on the surface of certain hemopoietic cells and it is considered to be the low affinity receptor for immunoglobulin IgE, (FcεRll/CD23). The regulation of the expression of CD23 depends on the type of cell on which it is found. Like most of the FcR receptors, it is released in a soluble form (sCD23) in the extracellular fluid. This form is found in increased levels in the serum of allergic patients and in neoplastic diseases. We studied total IgE and sCD23 in the serum of 30 allergic patients undergoing immunotherapy, 15 allergic patients treated only symptomatically for grass pollen (GP) allergy, 15 healthy and subjects. We found that the mean values of total IgE and sCD23 after the course of hyposensitization were decreased compared to those before treatment as well as to those GP allergic patients under conventional therapy and to healthy adults. However, only the CD23 decrease was statistically significant. Therefore, we speculate that determination of sCD23 may be useful for (a) the general evaluation of allergic patients and (b) the immunological monitoring of patients under immunotherapy.

Prognostic role of APC and RASSF1A promoter methylation status in cell free circulating DNA of operable gastric cancer patients

Gastric carcinogenesis is a multistep process including not only genetic mutations but also epigenetic alterations. The best known and more frequent epigenetic alteration is DNA methylation affecting tumor suppressor genes that may be involved in various carcinogenetic pathways. The aim of the present study was to investigate the methylation status of APC promoter 1A and RASSF1A promoter in cell free DNA of operable gastric cancer patients. Using methylation specific PCR, we examined the methylation status of APC promoter 1A and RASSF1A promoter in 73 blood samples obtained from patients with gastric cancer. APC and RASSF1A promoters were found to be methylated in 61 (83.6%) and 50 (68.5%) of the 73 gastric cancer samples examined, but in none of the healthy control samples (p < 0.001). A significant association between methylated RASSF1A promoter status and lymph node positivity was observed (p = 0.005). Additionally, a significant correlation between a methylated APC promoter and elevated CEA (p = 0.033) as well as CA-19.9 (p = 0.032) levels, was noticed. The Kaplan-Meier estimates of survival, significantly favored patients with a non-methylated APC promoter status (p = 0.008). No other significant correlations between APC and RASSF1A methylation status and different tumor variables examined was observed. Serum RASSF1A and APC promoter hypermethylation is a frequent epigenetic event in patients with early operable gastric cancer. The observed correlations between APC promoter methylation status and survival as well as between a hypermethylated RASSF1A promoter and nodal positivity may be indicative of a prognostic role for those genes in early operable gastric cancer. Additional studies, in a larger cohort of patients are required to further explore whether these findings could serve as potential molecular biomarkers of survival and/or response to specific treatments.

Pharmaceutical innovation: impact on expenditure and outcomes and subsequent challenges for pharmaceutical policy, with a special reference to Greece

Over the recent decades, advances in healthcare technology have led to significant improvements in the quality of healthcare and in population health. At the same time, technological change in healthcare, rising national income and expansion of insurance coverage have been acknowledged as the main determinants of the historical growth in health spending in industrialized countries. The pharmaceutical sector is of particular interest as it constitutes a market characterized by rapid technological change and high expenditure growth rates. The purpose of this article is to provide an overview of research findings on the impact of pharmaceutical innovation on pharmaceutical expenditure growth, total health expenditure and population health outcomes and to bring forward the challenges that arise for pharmaceutical policy in Greece.

Immature malignant sacrococcygeal teratoma: case report and review of the literature

Immature malignant sacrococcygeal teratoma (SCT) is a rare tumor, deriving from the three germinal layers and is found in the sacrococcygeal region. It is the most frequent site of teratomas in the fetus. A nut-brown, solid tumor with cystic areas with a ten-cm diameter is reported in the sacrococcygeal region of a female fetus of 23 weeks and with a weight of 308 g. The ultrasound and pathology evaluations revealed characteristics of an immature malignant SCT. The incidence of this tumor type is one in 35,000 to 40,000 live births and females are four times more likely to be affected than males. Sacrococcygeal and cervical teratomas can be diagnosed by prenatal ultrasound and magnetic resonance imaging (MRI). Teratomas are considered an interesting field for research.

Molecular diagnosis of CMV infection in fetal aborted tissues in the region of Thrace

PURPOSE

To detect the incidence of CMV infection in spontaneous abortion in Thrace.

METHODS

Genetic material from 143 fetuses aged from 11 to 39 weeks was examined. The material originated from various regions of Thrace. All fetuses and the respective placentas underwent routine histopathology. DNA was isolated from sections of paraffinized tissues. Detection of CMV in the DNA genomic samples was performed using a commercial PCR-based detection kit.

RESULTS

From the 143 fetuses that were examined, two were found to be CMV positive. Pathological findings related to inflammatory corruptions were observed in the placentas of 97 embryos, including the CMV infected ones.

CONCLUSIONS

This study indicates CMV-DNA infection in 1.4% of aborted fetuses. CMV infection incidence in aborted fetuses is similar to this reported in other European regions. The molecular technique of PCR applied on paraffin-embedded biopsy material is proven to be an accurate, valid and fast method for investigating the CMV infection in aborted fetuses.

Molecular pathogenesis of pancreatic cancer and clinical perspectives

Pancreatic cancer remains stubbornly resistant to many key cytotoxic chemotherapeutic agents and novel targeted therapies. The molecular heterogeneity of this cancer may account for therapy failures to date, although our growing arsenal of novel targeted agents could translate into patient survival. The main objectives of this review are to elucidate histological subtypes of pancreatic neoplasms that exhibit the characteristic of a gradual process of differentiation from benign entities to malignant ones. In addition, important genes, molecular abnormalities, and significant pathways of pancreatic cancer are analyzed and a potential clinical interpretation is presented (p16/cdkn2a, k-ras mutations, smad-4/tgf-/stat3, stk-11, braf, brca-2, neurotensin, mucs proteins, palb2, mitochondrial mutations, DNA mismatch repair genes, methylation, microrna expression, epithelial-to-mesenchymal transition, egfr mutations, the pi3k-akt-mtor pathway, the vegf pathway, heat shock proteins, cxcr4, the cox pathway, the src pathway, the hedgehog pathway, pancreatic stellate cells, a progression model, and molecular events in uncommon pancreatic tumors). Finally, future therapeutic directions are elucidated.

Macrolides: from in vitro anti-inflammatory and immunomodulatory properties to clinical practice in respiratory diseases

BACKGROUND

Macrolides have long been recognised to exert immunomodulary and anti-inflammatory actions. They are able to suppress the "cytokine storm" of inflammation and to confer an additional clinical benefit through their immunomodulatory properties.

METHODS

A search of electronic journal articles was performed using combinations of the following keywords: macrolides, COPD, asthma, bronchitis, bronchiolitis obliterans, cystic fibrosis, immunomodulation, anti-inflammatory effect, diabetes, side effects and systemic diseases.

RESULTS

Macrolide effects are time- and dose-dependent, and the mechanisms underlying these effects remain incompletely understood. Both in vitro and in vivo studies have provided ample evidence of their immunomodulary and anti-inflammatory actions. Importantly, this class of antibiotics is efficacious with respect to controlling exacerbations of underlying respiratory problems, such as cystic fibrosis, asthma, bronchiectasis, panbrochiolitis and cryptogenic organising pneumonia. Macrolides have also been reported to reduce airway hyper-responsiveness and improve pulmonary function.

CONCLUSION

This review provides an overview on the properties of macrolides (erythromycin, clarithromycin, roxithromycin, azithromycin), their efficacy in various respiratory diseases and their adverse effects.

Distinct distribution of corticotropin releasing factor receptors in human breast cancer

The hypothalamic neuropeptide corticotropin releasing factor (CRF) has been found in several types of human cancer, where its biological role is not clarified. In experimental models of breast cancer CRF has been shown to exert anti-proliferative and other actions. Aim of the present study was to describe the expression of the two types of CRF receptors CRF(1) and CRF(2) in human breast tumors. Receptor expression was studied in breast biopsies from patients diagnosed for primary breast adenocarcinoma, obtained from the tumor and the adjacent benign tissue. Gene expression levels were evaluated by real-time PCR following reverse transcription of total RNA extracts. CRF(1) transcripts were found in 23.1% of benign and in 23.1% of malignant biopsies. CRF(2(a)) was found in 22.2% of benign and 36.0% of malignant biopsies. Transcript levels of both receptors did not differ significantly between cancer and benign biopsies from the same tumor. No correlation was found between CRF receptor expression and patient histo/clinicopathological characteristics. Histological mapping using immunohistochemistry revealed positive CRF(1) immunostaining in the cancerous implants and breast ducts, whereas CRF(2) immunoreactivity was localized mainly in the perineural invasions. In conclusion, both CRF receptors were found in breast cancer and the respective benign adjacent tissue. The two CRF receptor proteins presented distinct distribution and subcellular localization, pointing into differing biological roles. CRF receptors could serve as targets of endogenous ligands expressed in the tumor microenvironment, regulating cancer growth.

The corticotropin-releasing factor (CRF) family of peptides as local modulators of adrenal function

Corticotropin-releasing factor (CRF), also termed corticotropin-releasing hormone (CRH) or corticoliberin, is the major regulator of the adaptive response to internal or external stresses. An essential component of the adaptation mechanism is the adrenal gland. CRF regulates adrenal function indirectly through the central nervous system (CNS) via the hypothalamic-pituitary-adrenal (HPA) axis and via the autonomic nervous system by way of locus coeruleus (LC) in the brain stem. Accumulating evidence suggests that CRF and its related peptides also affect the adrenals directly, i.e. not through the CNS but from within the adrenal gland where they form paracrine regulatory loops. Indeed, CRF and its related peptides, the urocortins (UCNs: UCN1, UCN2 and UCN3), their receptors CRF type 1 (CRF(1)) and 2 (CRF(2)) as well as the endogenous pseudo-receptor CRF-binding protein (CRF-BP) are all expressed in adrenal cortical, medullary chromaffin and resident immune cells. The intra-adrenal CRF-based regulatory system is complex and depends on the balance between the local concentration of CRF ligands and the availability of their receptors.

Corticotropin-releasing factor (CRF) and the urocortins differentially regulate catecholamine secretion in human and rat adrenals, in a CRF receptor type-specific manner

Corticotropin-releasing factor (CRF) affects catecholamine production both centrally and peripherally. The aim of the present work was to examine the presence of CRF, its related peptides, and their receptors in the medulla of human and rat adrenals and their direct effect on catecholamine synthesis and secretion. CRF, urocortin I (UCN1), urocortin II (UCN2), and CRF receptor type 1 (CRF1) and 2 (CRF2) were present in human and rat adrenal medulla as well as the PC12 pheochromocytoma cells by immunocytochemistry, immunofluorescence, and RT-PCR. Exposure of dispersed human and rat adrenal chromaffin cells to CRF1 receptor agonists induced catecholamine secretion in a dose-dependent manner, an effect peaking at 30 min, whereas CRF2 receptor agonists suppressed catecholamine secretion. The respective effects were blocked by CRF1 and CRF2 antagonists. CRF peptides affected catecholamine secretion via changes of subplasmaliminal actin filament polymerization. CRF peptides also affected catecholamine synthesis. In rat chromaffin and PC12 cells, CRF1 and CRF2 agonists induced catecholamine synthesis via tyrosine hydroxylase. However, in human chromaffin cells, activation of CRF1 receptors induced tyrosine hydroxylase, whereas activation of CRF2 suppressed it. In conclusion, it appears that a complex intraadrenal CRF-UCN/CRF-receptor system exists in both human and rat adrenals controlling catecholamine secretion and synthesis.

CRF receptor antagonists: utility in research and clinical practice

CRF, CRF-related peptides and CRF receptors constitute a complex physiological system which has a key role in facilitating the adaptation of the organism to the stressful stimuli of the environment. The behavioral, endocrine, autonomic and immune branches of stress response are considered to be under the coordinating effects of CRF and its related peptides. The effects of these peptides are mediated through two distinct receptors, types 1 and 2 CRF receptors (CRF(1) and CRF(2)). The two receptors are encoded by separate genes and belong to the G-coupled receptor superfamily. The wide influence of the CRF system on physiological processes in both brain and periphery, suggests the implication of the respective peptides in the pathophysiology of numerous disorders which involve dysregulated stress responses. The potential use of CRF antagonists in such disorders is currently under intense investigation. Furthermore, such compounds have been invaluable in elucidating the physiology of the CRF system. This review will focus on existing data on the structural and pharmacological characteristics as well as the experimental and potential clinical uses of non-peptide, small molecule CRF antagonists.

A Dose Escalation Study of Docetaxel Plus Capecitabine in Combination With Gemcitabine in Patients With Advanced Solid Tumors

Capecitabine (CAP), gemcitabine (GEM), and docetaxel (DOC) have shown interesting activity in a wide range of solid tumors. A phase I study was conducted in order to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of their combination in patients with refractory solid tumors. Eighteen patients were enrolled. The patients' median age was 60 years, 15 were male, and 11 were chemo-naive. DOC was administered on day 1 as an 1-h (IV) infusion at escalating doses ranging from 40 to 50 mg/m2. GEM was administered on day 1 as a 30-min (IV) infusion at a standard dose of 1500 mg/m2. CAP was administered orally on days 1 to 7 at escalating doses ranging from 1750 to 2500 mg/m2 given as two daily divided doses. Treatment was repeated every 2 weeks. Five different dose levels were examined. At dose level V two out of three enrolled patients presented DLTs (one patient grade 4 neutropenia and grade 3 stomatitis and another grade 3 diarrhea), and thus the recommended MTD for future phase II studies are CAP 2250 mg/m2, DOC 50 mg/m2, and GEM 1500 mg/m2. A total of 124 treatment cycles were administered. Toxicity was generally mild. Grade 3/4 neutropenia was observed in eight (7%) treatment cycles and grade 3 thrombocytopenia in one (1%). There was no febrile episode. Grade 2/3 asthenia was observed in six (33%) patients, grade 2/3 diarrhea in four (22%), and grade 2/3 hand-foot syndrome in three (17%). Other toxicities were uncommon. There was no treatment-related death. One (6%) CR, four (25%) PRs, and six (38%) SD were observed among 16 evaluable patients. Responses were seen in patients with breast (one CR), gastric (three PRs), and pancreatic (one PR) cancer. These results demonstrate that CAP, DOC, and GEM can be safely combined at clinically relevant doses and this regimen merits further evaluation.

A Dose Escalation Study of Pegylated Liposomal Doxorubicin (Caelyx) in Combination with Capecitabine (Xeloda) in Patients with Refractory Solid Tumors

OBJECTIVE

Pegylated liposomal doxorubicin (PLD) and capecitabine (CAP) have separately shown significant antitumor activity in a wide range of solid tumors. A phase I study was conducted in order to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of their combination in patients with refractory solid tumors.

PATIENTS AND METHODS

Fifteen patients with histologically confirmed inoperable solid neoplasms were enrolled. The patients' median age was 65 years, 10 were male, and 12 had a performance status score (WHO) of 0-1. PLD was administered on day 1 as a 1-hour intravenous infusion at escalated doses ranging from 35 to 40 mg/m(2). CAP was administered on days 1-14 per os, at escalated doses ranging from 1,600 to 1,800 mg/m(2), given as two daily divided doses. Treatment was repeated every 3 weeks.

RESULTS

At the dose of PLD 40 mg/m(2) and CAP 1,800 mg/m(2), all 3 enrolled patients presented DLTs [2 patients grade 3 palmar-plantar erythrodysesthesia (PPE) and 1 patient grade 3 asthenia] and thus, the recommended MTD for future phase II studies is PLD 40 mg/m(2) and CAP 1,700 mg/m(2). A total of 57 treatment cycles were administered. Grade 2/3 neutropenia complicated 9 (17%) cycles and 1 patient was hospitalized for febrile neutropenia. There was no septic death. The main nonhematologic toxicity was PPE grade 2 in 3 (19%) patients and grade 3 in 4 (27%). PPE was the reason of treatment interruption for 3 patients. Other toxicities were mild and easily manageable. Two patients (16%) with partial response suffering from gastric cancer and 5 patients with (42%) stable disease were observed among 12 evaluable patients.

CONCLUSIONS

The results of this phase I study demonstrate that PLD and CAP can be combined at clinically effective and relevant doses. However, PPE is a common side effect and further investigation is warranted to define its precise role in the treatment of solid malignancies.

Transforming growth factor beta1 exerts an autocrine regulatory effect on human endometrial stromal cell apoptosis, involving the FasL and Bcl-2 apoptotic pathways

Transforming growth factor beta1 (TGFbeta1) is expressed in human endometrium. It regulates epithelial cell proliferation and apoptosis. The aim of the present work was to examine the role of TGFbeta1 on human endometrial stromal cell apoptosis. Primary cultures of isolated stromal cells were obtained from biopsies of late secretory phase endometrium. We have found the following: (i) TGFbeta1 induced apoptosis of stromal cells in a time- and dose-dependent manner; (ii) blockade of TGFbeta1's autocrine/paracrine effect by TGFbeta1-neutralizing antibodies diminished the basal rate of stromal cell apoptosis; (iii) semi-quantitative Western blot analysis showed that TGFbeta1 caused a rapid but transient elevation of the pro-apoptotic FasL protein, without affecting the levels of Fas receptor; (iv) TGFbeta1 increased the levels of the anti-apoptotic Bcl-2 and Bcl-xL proteins, while having no significant effects on the pro-apoptotic proteins Bax and Bak, suggesting the activation of a transient survival mechanism activated in stromal cells as a parallel rescue response to the apoptosis-inducing FasL protein. In conclusion, our data provide evidence that TGFbeta1 exerts an autocrine pro-apoptotic effect on human endometrial stroma, via the FasL/Fas system.

Urocortin in human gastric mucosa: relationship to inflammatory activity

The presence of CRH and urocortin (Ucn), members of the CRH family of neuropeptides, was examined in human gastric biopsies from normal controls and in patients with active gastritis from Helicobacter pylori (H. pylori) and after eradication treatment. RT-PCR analysis showed the presence of the Ucn transcript in biopsies (obtained by gastroscopy) from normal and inflamed gastric mucosa, whereas the CRH transcript was not detectable. Immunoreactive (ir-) Ucn was localized (by immunohistochemistry) in gastric epithelial cells and in inflammatory elements of the surrounding negative for Ucn gastric stroma. The level of ir-Ucn was higher in gastric biopsies from the group of patients with active H. pylori gastritis than in normal controls (10.4 +/- 1.8 vs. 2.0 +/- 1.3 pg/ micro g total protein; P < 0.001). After the apparent eradication of H. pylori infection (by clinical and morphological criteria) ir-Ucn levels increased dramatically to 43.1 +/- 9.8 pg/ micro g total protein, (P < 0.001) compared with pretreatment values. Interestingly, nonresponders to the eradication treatment did not show any significant change in ir-Ucn levels (18.7 +/- 12.3 pg/ micro g total protein) compared with their pretreatment values. In conclusion, our data suggest that in human gastric epithelium Ucn is present and plays an important physiological role, whereas CRH is absent. In addition, and in contrast to what has been found for CRH in ulcerative colitis, a highly significant, but negative, correlation has been found between Ucn levels and gastric inflammation, suggesting that Ucn may exert an antiinflammatory effect in gastric mucosa.

Expression and regulation of corticotropin-releasing hormone binding protein (CRH-BP) in rat adrenals

Corticotropin-releasing hormone (CRH) is present in the adrenal gland acting as a paracrine factor via stimulation of the locally expressed CRH receptors. In this study, we examined if the adrenal CRH system also contains a key component of the neuronal CRH-containing system, the CRH-binding protein (CRH-BP). Our data show that: (i) the CRH-BP transcript is detectable using RT-PCR in total RNA isolated from rat adrenals, and (ii) its protein product is also found by western blot analysis in cell lysates. (iii) Immunohistochemical staining showed that adrenomedullary chromaffin cells produce the bulk of adrenal CRH-BP, an ability retained by the PC12 rat pheochromocytoma cell line. (iv) Regulation of adrenal CRH-BP expression by major modulators of the CRH system was also examined. Protein expression appears to be under the positive control of CRH itself, protein kinase A effector cAMP, glucocorticoids and interleukin (IL)-6. It is thus evident that CRH-BP may play a role in mediating their effects in the adrenal. (v) Differentiation of PC12 into neuron-like cells resulted in a significant increase in CRH-BP, parallel to the induction of the CRH peptide itself. In conclusion, CRH-BP mRNA and protein are present in normal rat adrenomedullary chromaffin cells and in the PC12 rat pheochromocytoma cell line, making the adrenal CRH system directly comparable with those described in the CNS.

The Fas/FasL apoptotic pathway is involved in kappa-opioid-induced apoptosis of human endometrial stromal cells

Human endometrium expresses specific kappa-opioid binding sites and their endogenous ligands, the dynorphins. In neural crest-derived tissues, kappa-opioids affect apoptosis, a phenomenon of major significance in endometrial stroma physiology. Our hypothesis was that endometrial kappa-opioids may play a role in endometrial stromal cell apoptosis. Thus, we examined the effect of the synthetic kappa-opioid agonist, U69593, on the apoptotic rate of human endometrial stromal cells in primary culture. Apoptosis of endometrial stromal cells was elevated after 3 h exposure to 100 nmol/l U69593, and remained elevated for up to 3 days. This effect was dose-dependent and was reversed by the general opioid antagonist, naloxone, suggesting that it is mediated via opioid receptors. In parallel, semi-quantitative Western blot and flow cytometry analysis showed that U69593 caused a rapid but transient up-regulation of Fas protein, suggesting that its effect on apoptosis is mediated by activation of the Fas/FasL apoptotic pathway. Additionally, U69593 increased the content of the anti-apoptotic members of the Bcl-2 family of proteins, the Bcl-2 and Bcl-x(L), whereas it had no significant effect on the apoptosis-promoting homologues Bax, Bcl-x(S) and Bak. This implies that a transient survival mechanism is activated in stromal cells as a parallel rescue response to the apoptosis-inducing factor. In conclusion, our data suggest that endometrial opioid dynorphins may participate in the apoptotic processes related to endometrial tissue remodelling during early pregnancy or menstruation.

Growth and characterization of a cell line from a human primary neuroendocrine carcinoma of the skin (Merkel cell carcinoma) in culture and as xenograft

The primary neuroendocrine carcinoma of the skin or Merkel cell carcinoma (MCC) is a skin tumor with aggressive biological behaviour. Experimental models for investigating the biological properties of the tumor are prerequisite for developing new therapeutic approaches. In this study, we report the establishment and characterisation of a cell line derived from the lymph-node metastasis of a patient with highly aggressive MCC. Merkel carcinoma cells (MCC-1) grew as floating aggregates in suspension cultures for more than two years and over 70 subcultures. The proliferation rate in suspension cultures was rather moderate with a population doubling time of 69 h. The immunocytochemical pattern of the cultured MCC-1 was similar to that of the original tumor with expression of cytokeratin 18, neuron-specific enolase, neurofilaments, and synaptophysin. In addition, reverse transcriptase polymerase chain reaction (RT-PCR) revealed presence of chromogranin A mRNA in the MCC-1 cell line. Furthermore, electron microscopy yielded the rare finding of neuroendocrine granules in the cytoplasm of the cultured cells. The cell line MCC-1 was able to form colonies in soft agar. Nude mice developed solid tumors with similar histology to the original tumor after subcutaneous and intravenous injections of cultured MCC-1, and malignant ascites was seen after intraperitoneal injection. Also, two MCC-1 sublines were established by reculturing cells from the xenografts grown in vivo and immunocytochemistry confirmed their neuroendocrine origin. The MCC-1 line may thus serve as a model for studying the biology and the metastatic potential of Merkel cell carcinoma.

Cycle and age-related changes in corticotropin-releasing hormone levels in human endometrium and ovaries

Corticotropin-releasing hormone (CRH) is synthesized in most female reproductive tissues such as the ovaries and the uterus. In the non-pregnant uterus, it is mainly produced by epithelial cells of the endometrium. Recent in vitro experimental findings show that endometrial CRH is under the positive control of progesterone, participating in the decidualization process of endometrial stroma and the progression of blastocyst implantation. CRH is also produced in the thecal compartment of the human ovary, controlling ovarian steroid hormone biosynthesis. In the present study we compared the concentration of immunoreactive CRH (ir-CRH) in biopsies from proliferative and secretory human endometria, and from pre- and postmenopausal human ovaries. We found that the concentration of ir-CRH was significantly higher in the secretory (92 +/- 8 pg/mg protein; n = 10) than the proliferative (75 +/- 9 pg/mg protein; n = 12; p < 0.05) endometria. This observation supports the experimental in vitro findings associating endometrial CRH in intrauterine phenomena of the secretory phase of the menstrual cycle (decidualization and implantation). Additionally, we have shown that the concentration of ir-CRH was significantly higher in the premenopausal (125 +/- 12 pg/mg protein; n = 14) than the postmenopausal (100 +/- 12 pg/mg protein; n = 12; p < 0.05) ovaries, suggesting that ovarian CRH is related to normal ovarian function during the reproductive lifespan.

Regulation of endometrial cancer cell growth by luteinizing hormone (LH) and follicle stimulating hormone (FSH)

Gonadotrophin releasing hormone analogues (GnRHa) have been used to treat recurrent endometrial cancer. However, the mode of action is uncertain. Our previous studies showed no direct effect of GnRHa on endometrial cancer cell growth in vitro. We have now examined the effect of luteinizing hormone (LH) and follicle stimulating hormone (FSH) on endometrial cancer cell growth. The aim was to determine whether suppression of pituitary LH and FSH by GnRHa could explain the tumour regression seen in up to 44% of patients treated with this drug. We show that recombinant human LH and FSH (rhLH and rhFSH) produce a concentration dependent stimulation of the endometrial cancer cell line HEC-1A, in serum-free medium (maximum increase of 62 and 50% respectively relative to untreated controls). This increase is equivalent to that obtained by addition of 10% newborn calf serum. Growth of the Ishikawa cell line in culture increases in the presence of rhLH (maximum increase of 67%) but not with rhFSH. Using RT-PCR, we show that the Ishikawa cell line intermittently expresses receptor mRNA of LH but not of FSH; there is no expression of either mRNA by HEC-1A. Classically, both LH and FSH act via cAMP linked membrane receptors. However, neither rhLH nor rhFSH elicit cAMP production in either of our endometrial cancer cell lines. Thus, although a growth response to LH and FSH can be shown, and some cells express the LH receptor, stimulation appears to be via a pathway separate from that of the classical gonadotrophin receptor.

Kappa opioids and TGFbeta1 interact in human endometrial cells

The transforming growth factor beta1 (TGFbeta1) is a major regulator of human endometrial function. Human endometrium possesses specific opioid binding sites, the majority of which belong to the kappa type, for which the prodynorphin-derived opioids are the endogenous ligands. Since these two systems interact in several other tissues we postulated that opioids may affect the production of TGFbeta1 in human endometrium. We have found that kappa opioids exerted a time- and dose-dependent inhibitory effect on TGFbeta1 production from endometrial stromal and epithelial cells and from the Ishikawa human endometrial adenocarcinoma cell line. This effect was reversible by the specific opioid antagonist diprenorphine. To examine if this effect represents a paracrine endometrial response to locally produced kappa opioids we searched for the presence of the endogenous kappa opioid receptor ligands. Indeed, the prodynorphin transcript was detectable on Northern blots from normal and tumoral human endometrial cells; its size was that of the pituitary transcript, i.e. approximately 2.4 kb long. Most immunoreactive dynorphin from human endometrium had a molecular weight of 8 kDa. Finally, immunofluorescence staining of normal and tumoral human endometrial cells revealed the presence of dynorphin-positive cytoplasmic secretory granules. Taken together, our data suggest that in human endometrium, kappa opioids and the TGFbeta1 form a paracrine network which appears to be retained by the Ishikawa human endometrial adenocarcinoma cell line.

Opioids transiently prevent activation of apoptotic mechanisms following short periods of serum withdrawal

Opioids exert a proapoptotic effect on several normal and tumoral cells. The aim of the present article was to examine the effect of opioids on the PC12 rat pheochromocytoma cell line, a model for the study of chromaffin cell apoptosis. These cells produce delta- and kappa-opioid agonists and their receptors. Our results were as follows: The kappa- and delta2-opioid receptor agonists had a rapid but transient effect on apoptosis at 3 h, whereas mu opioids did not. The effect of opioids was reversible by the opioid antagonists naloxone and nor-binaltorphimine. The effect of opioids was protective, suppressing serum deprivation-induced apoptosis to approximately 50% of controls. The protective effect of opioids on PC12 apoptosis was measurable only under serum deprivation. The effect of opioids was remarkably reproducible and highly constant in timing, which did not appear to depend on the duration of the preceding serum deprivation. Finally, opioids prevented the elevation of the Bcl-2 and Bak proteins following serum deprivation to the levels attained by serum supplementation. Our combined data suggest that opioids protect PC12 cells from entering a state of induced apoptosis following serum deprivation.

The decidualizing effect of progesterone may involve direct transcriptional activation of corticotrophin-releasing hormone from human endometrial stromal cells

The hypothalamic neuropeptide corticotrophin-releasing hormone (CRH) is also produced by human endometrial cells and is directly involved in the decidualization process as a paracrine inducer. The aim of the present work was to examine the effect of progesterone, the main decidualizing factor, on endometrial CRH, in primary cultures of human endometrial stromal cells. The effect of progesterone was examined by measuring the effects of medroxyprogesterone acetate (MPA) on (i) the concentration of immunoreactive CRH in isolated human endometrial stromal cells and (ii) the activity of the CRH promoter in human endometrial stromal cells transfected with a 0.9 kb fragment of the 5'-flanking region of the human CRH gene coupled to luciferase reporter. The data show that MPA increased the production and secretion of immunoreactive CRH from stromal cells and induced the activity of the CRH promoter, both in a dose-dependent manner. These effects were partially reversed by a molar excess of the antiprogestin RU 486 and were completely abolished in the presence of 100 nmol/l of the cAMP inhibitor, Rp-cAMP. The effect of progesterone on the CRH promoter requires the existence of an intact CRH sequence since experiments carried out with a deleted palindromic cAMP response element (CRE: 5'-TGACGTCA) at -224 bp of the CRH promoter resulted in a complete loss of MPA effect. In conclusion, these data provide evidence that progesterone induces the transcription of CRH gene in human endometrial stroma. This effect coupled with the decidualizing properties of progesterone and CRH may indicate that progesterone and CRH form a decidualizing local pathway within the human endometrium.

The expression of gonadotropin-releasing hormone and its receptor in endometrial cancer, and its relevance as an autocrine growth factor

The presence of a direct extra-pituitary action of gonadotropin-releasing hormone (GnRH) via specific receptors in endometrial cancer (EC) has been suggested as an explanation for the therapeutic effect of GnRH analogue (GnRHa) in recurrent disease. We have sought the expression of the GnRH peptide and functional GnRH receptor (GnRH-R) in human tissues and cell lines to investigate the possibility of an autocrine growth regulation mechanism. Using reverse transcription-PCR, differing GnRH mRNA transcripts were detected in two EC cell lines (Ishikawa and HEC-1A), a choriocarcinoma (JEG3) cell line, and tissues from endometrium and placenta. However, secretion of immunoreactive GnRH could be detected by RIA in only 1 of 10 EC tissues in primary culture, and in none of the cell lines. Low levels of GnRH-R mRNA expression were found in the same cells, which were only detectable by reverse transcription-PCR and Southern blotting of the PCR product. In radioligand binding assays using GnRHa goserelin, no pituitary-like, high-affinity GnRH binding sites could be found in either EC cell lines or tissues. Low affinity binding (Kd = 1.0 - 3.1 x 10(-7)M) was detected in three of eight (37%) EC tissues. Furthermore, receptor signal transduction measurements carried out in these cells showed no increases in either total inositol phosphate, cyclic AMP production, or cytosolic Ca2+ in response to either GnRH or GnRHa. Finally, no effect of either GnRH or GnRHa on the growth of EC cell lines was detected in vitro, under estrogen-free conditions, assessed by DNA content. Our data suggest that although there is a potential for autocrine activity for GnRH in EC as judged by the presence of mRNA for peptide and receptor, no functional receptor activity could be detected in vitro. Alternative mechanisms should be studied to explain the in vitro action of GnRHa.

Characterisation of the differential expression of marker antigens by normal and malignant endometrial epithelium

In order to examine the production of marker proteins, a reproducible method has been established for culturing purified epithelial cells from normal and malignant endometrium. We have examined the differential expression of secretory proteins using immunohistochemistry in frozen tissue sections, immunocytochemistry in cell cultures derived from the same specimens and protein assays on the culture supernatants. Placental protein 14 (PP14) was produced by normal premenopausal epithelium but not by the post-menopausal or malignant endometrial epithelium. In contrast, placental alkaline phosphatase (PLAP) was produced by endometrial cancers and the endometrial adenocarcinoma-derived cell line Ishikawa, but not by the normal endometrial epithelium. Other markers such as CA-125, which was produced by both normal and malignant endometrium but not by the cell line, and human chorionic gonadotrophin (beta-hCG), which was produced by Ishikawa cells but not by any of the fresh tissues, were less cancer specific. Placental alkaline phosphatase is a direct product of endometrial cancers that can be readily assayed in serum using this two-site assay to test its clinical usefulness in monitoring patients at risk for endometrial cancer.