Deregulated ephrin-B2 expression in the mammary gland interferes with the development of both the glandular epithelium and vasculature and promotes metastasis formation

Eph receptor tyrosine kinases and their membrane-bound ephrin ligands play key roles during morphogenesis and adult tissue homeostasis. Receptor-ligand interactions result in forward and reverse signalling from the receptor and ligand respectively. To delineate the role(s) of forward and reverse signalling in mammary gland biology we have established transgenic mice exhibiting mammary epithelial-specific overexpression of either the native ephrin-B2 or a dominant negative ephrin-B2 mutant incapable of reverse signalling. During pregnancy and lactation overexpression of the native ephrin-B2 resulted in precocious differentiation, whereas overexpression of mutated ephrin-B2 caused delayed epithelial differentiation and in disturbed tissue architecture. Both transgenes affected also mammary vascularisation. Whereas ephrin-B2 induced superfluous but organised capillaries, mutant ephrin-B2 overexpression resulted in an irregular vasculature with blind-ending capillaries. Mammary tumours were not observed in either transgenic line, however, the crossing with NeuT transgenic animals revealed that mutated ephrin-B2 expression significantly accelerated tumour growth and imposed a metastatic phenotype.

Clinical and histological characterization of hair coat and glandular tissue of Chinese crested dogs.

BACKGROUND Two varieties exist in the Chinese crested dog breed, namely hairless Chinese crested dogs presenting with hypotrichosis and dentition abnormalities, and the coated powderpuffs. Hairless Chinese crested dogs are obligate heterozygotes for a FOXI3 mutation, and this phenotype is classified as a form of canine ectodermal dysplasia. OBJECTIVES We provide a detailed histological description of hair follicles and their density for the three subphenotypes (true hairless, semi-coated and powderpuffs) of Chinese crested dogs. Apocrine and exocrine glands of the skin and other tissues were compared with findings reported from dogs with X-linked ectodermal dysplasia. ANIMALS Skin biopsies were collected from 22 Chinese crested dogs. Additionally, the glands of the skin and other tissues were examined from another two dogs available for postmortem examination. METHODS Skin biopsies and tissues were processed, stained and evaluated in a blinded fashion. RESULTS Hair follicular anomalies decreased with increasing number of hairs in the different phenotypes. The FOXI3 mutants had only simple primary hair follicles, whereas the nonmutant powderpuffs had compound follicles identical to other dog breeds. All Chinese crested dogs had an anagen-dominated hair cycle. Furthermore, apocrine glands in the skin and respiratory mucous glands of the mutant Chinese crested dogs were present and normal. CONCLUSIONS AND CLINICAL IMPORTANCE We have identified striking histopathological differences between the three subphenotypes of Chinese crested dogs. We clearly demonstrated distinct differences between the canine ectodermal dysplasia in Chinese crested dogs and dogs with X-linked ectodermal dysplasia.

Expression, localization, and functional model of cholesterol transporters in lactating and nonlactating mammary tissues of murine, bovine, and human origin

Members of the ATP-binding cassette (ABC) transporters play a pivotal role in cellular lipid efflux. To identify candidate cholesterol transporters implicated in lipid homeostasis and mammary gland (MG) physiology, we compared expression and localization of ABCA1, ABCG1, and ABCA7 and their regulatory genes in mammary tissues of different species during the pregnancy-lactation cycle. Murine and bovine mammary glands (MGs) were investigated during different functional stages. The abundance of mRNAs was determined by quantitative RT-PCR. Furthermore, transporter proteins were localized in murine, bovine, and human MGs by immunohistochemistry. In the murine MG, ABCA1 mRNA abundance was elevated during nonlactating compared with lactating stages, whereas ABCA7 and ABCA1 mRNA profiles were not altered. In the bovine MG, ABCA1, ABCG1, and ABCA7 mRNAs abundances were increased during nonlactating stages compared with lactation. Furthermore, associations between mRNA levels of transporters and their regulatory genes LXRalpha, PPARgamma, and SREBPs were found. ABCA1, ABCG1, and ABCA7 proteins were localized in glandular MG epithelial cells (MEC) during lactation, whereas during nonlactating stages, depending on species, the proteins showed distinct localization patterns in MEC and adipocytes. Our results demonstrate that ABCA1, ABCG1, and ABCA7 are differentially expressed between lactation and nonlactating stages and in association with regulatory genes. Combined expression and localization data suggest that the selected cholesterol transporters are universal MG transporters involved in transport and storage of cholesterol and in lipid homeostasis of MEC. Because of the species-specific expression patterns of transporters in mammary tissue, mechanisms of cholesterol homeostasis seem to be differentially regulated between species.

Antennal courtship and functional morphology of tyloids in the parasitoid wasp Syrphoctonus tarsatorius (Hymenoptera: Ichneumonidae: Diplazontinae)

Courtship behaviour and associated morphological characters are believed to evolve under diversifying sexual selection. In Hymenoptera, sexually dimorphic antennal structures, the 'tyloids', show a large variability. Although crucial for functional interpretation, the link between tyloid morphology and courtship behaviour has gained only limited attention. Here, we investigate antennal morphology and antennal courtship in the parasitoid wasp Syrphoctonus tarsatorius (Hymenoptera: Ichneumonidae: Diplazontinae). We confirm the glandular nature of the tyloids by light and scanning electron microscopy. Moreover, we report a new form of antennation during courtship, antennal double-coiling, which links morphology and behaviour by bringing the tyloids in direct contact with the antennae of the female, thus probably facilitating the transfer of a contact pheromone. We show that a change in haemolymph pressure is the activator of the antennal movement and that it can be reproduced in the laboratory using amputated antennae. Investigations of antennal structure and movement in three additional hymenopteran species suggest that the number and location of tyloids coincide with the modality of antennal coiling. Our method for simulating antennal movement will enable retrieving information about courtship behaviour from museum specimens, thus leading to a better understanding of the evolution of courtship behaviour in Hymenoptera.

Gastrointestinal tract mucosal histomorphometry and epithelial cell proliferation and apoptosis in neonatal and adult dogs

In this study, the hypothesis was tested that the size of gastrointestinal tract (GIT) mucosal components and rates of epithelial cell proliferation and apoptosis change with increasing age. The aims were to quantitatively examine GIT histomorphology and to determine mucosal epithelial cell proliferation and apoptosis rates in neonatal (<48 h old) and adult (8 to 11.5 yr old) dogs. Morphometrical analyses were performed by light microscopy with a video-based, computer-linked system. Cell proliferation and apoptosis of the GIT epithelium were evaluated by counting the number of Ki-67 and caspase-3-positive cells, respectively, using immunohistochemical methods. Thickness of mucosal, glandular, subglandular, submucosal and muscular layers, crypt depths, villus heights, and villus widths were consistently greater (P < 0.05 to P < 0.001), whereas villus height/crypt depth ratios were smaller (P < 0.001) in adult than in neonatal dogs. The number of Ki-67-positive cells in stomach, small intestine, and colon crypts, but not in villi, was consistently greater (P < 0.01) in neonatal than in adult dogs. In contrast, the number of caspase-3-positive cells in crypts of the stomach, small intestine, and colon and in villi was not significantly influenced by age. In conclusion, canine GIT mucosal morphology and epithelial cell proliferation rates, but not apoptosis rates, change markedly from birth until adulthood is reached.

Anticancer drug vinblastine sulphate induces transient morphological changes on the olfactory mucosa of the rabbit

Vinblastine sulphate (VBS) is an anticancer drug that acts by disrupting microtubule dynamics of highly mitotic tissue cells. The consequences of VBS on the olfactory mucosa (OM), a tissue with high mitotic numbers, are not clearly understood. We used qualitative and quantitative methods to determine the structural changes that may be produced on the rabbit OM by VBS. Following a single dose (0.31 mg/kg) of this drug, the structure of the mucosa was greatly altered on the first 3-5 days. The alteration was characterized by disarrangement of the normal layering of nuclei of the epithelia, degeneration of axonal bundles, occurrence of blood vessels within the bundles, localized death of cells of Bowman's glands and glandular degeneration. Surprisingly on or after day 7 and progressively to day 15 post-exposure, the OM was observed to regenerate and acquire normal morphology, and the vessels disappeared from the bundles. Relative to control values, bundle diameters, olfactory cell densities and cilia numbers decreased to as low as 53.1, 75.2 and 71.4%, respectively, on day 5. Volume density for the bundles, which was 28.6% in controls, decreased to a lowest value of 16.8% on day 5. In contrast, the volume density for the blood vessels was significantly lower in controls (19.9%) than in treated animals at day 2 (25.8%), day 3 (34.3%) and day 5 (31.5%). These findings suggest that the changes induced on the rabbit OM by VBS are transient and that regenerative recovery leads to the restoration of the normal structure of the mucosa.

Distribution of the glutamate transporters GLT-1 (SLC1A2) and GLAST (SLC1A3) in peripheral organs

The glutamate transporters GLT-1 and GLAST are widely expressed in astrocytes in the brain where they fulfill important functions during glutamatergic neurotransmission. The present study examines their distribution in peripheral organs using in situ hybridization (ISH) and immunocytochemistry. GLAST was found to be more widely distributed than GLT-1. GLAST was expressed primarily in epithelial cells, cells of the macrophage-lineage, lymphocytes, fat cells, interstitial cells, and salivary gland acini. GLT-1 was primarily expressed in glandular tissue, including mammary gland, lacrimal gland, and ducts and acini in salivary glands, but also by perivenous hepatocytes and follicular dendritic cells in spleen and lymph nodes. The findings demonstrate that, although expressed by the same cells in the brain, these two glutamate transporters have different distribution patterns in peripheral tissues and that they fulfill glutamate transport functions apart from glutamatergic neurotransmission in these areas.

[Primary malignant melanoma of the parotid gland: a case report and review of the literature]

Malignant melanomas (MMs) of the parotid gland are relatively uncommon. They occur almost invariably as metastases from a primary tumour located in the region of the scalp or the mucous membranes of the nose, paranasal sinuses, or throat. Primary MMs arising in the parotid gland are extremely rare. It is assumed that they originate in the glandular tissue or in intraglandular lymph nodes. We present a case report and review of the literature on the diagnosis, treatment, and prognosis of intraparotid malignant melanoma. Diagnosis is based primarily on B-scan ultrasonography and fine-needle aspiration cytology. Patients with a cytological diagnosis of MM are further evaluated by magnetic resonance imaging and positron emission tomography and receive a thorough ear-nose-throat and dermatological examination. The treatment of choice is total parotidectomy and selective neck dissection. The effectiveness of adjuvant treatments such as radiotherapy, chemotherapy, or immunotherapy remains controversial. Patients with primary MMs of the parotid gland appear to have a better prognosis than those with parotid metastases from melanomas of the skin or mucous membranes.

Management of chronic pancreatitis

Chronic pancreatitis (CP) is an inflammatory disorder that results in permanent impairment of the glandular anatomy of the pancreas with or without functional abnormalities. The pathogenesis of CP is usually unclear, except in the case of alcohol-induced disease. The most common symptoms of CP are abdominal pain, diarrhea, and weight loss often requiring recurring hospitalization. Over time, pancreatic endocrine and exocrine dysfunction may develop as the disease progresses, and a variety of complications can occur. Among the possible complications are nutrient malabsorption and diabetes mellitus. The treatment of CP is difficult and challenging for every physician. Relieving pain is the first step in treating CP. This symptom needs to be controlled, often with narcotics, which can cause dependence. Diarrhea usually indicates the presence of steatorrhea, which is often treated with a high-calorie, high-protein, and low-fat diet to minimize symptoms of the underlying disease and to promote weight retention or gain. Pancreatic replacement therapy is used to combat maldigestion and malabsorption. Patients with diabetes may need insulin therapy for glycemic control. The use of parenteral nutrition for bowel rest is a standard approach in patients with symptomatic CP. The use of jejunal enteral feeding recently has been evaluated for efficacy in CP patients. The role of pancreatic endotherapy in the management of CP is evolving. Several reports have suggested that endoscopic therapy aimed at decompressing the obstructed pancreatic duct can be associated with pain relief in some patients. Surgery should be considered in patients who fail medical therapy.

Evaluation of histological, serological and clinical changes in response to abatacept treatment of primary Sjögren's syndrome: A pilot study

Objectives To prospectively evaluate histopathologic, blood cellular, serological and clinical changes in response to abatacept treatment in patients with primary Sjögren's syndrome (pSS). Methods Blood, saliva and minor salivary gland biopsies were obtained before and after the last of 8 doses of abatacept in 11 pSS patients. The histologic data evaluated the number of lymphocytic foci and of B- and T-cell subtypes (CD20(+) , CD3(+) , CD4(+) , CD8(+) ). The numbers of FoxP3(+) regulatory T-cells were measured and the FoxP3 /CD 3 ratio was calculated. Histologic data were compared with results from peripheral blood and with changes in saliva secretion. Results The numbers of lymphocytic foci decreased significantly (p=0.041). Numbers of local FoxP3(+) T-cells decreased significantly in percentage of total lymphocytic infiltrates (p=0.037). In the peripheral blood B-cells increased (p=0.038). This was due to an expansion of the naïve B cell pool (p=0.034). When adjusting for disease duration, an increase was also noted for total lymphocytes (p=0.044) and for CD 4 cells (p=0.009). Gamma globulins decreased significantly (p=0.005), but IgG reduction did not reach significance. Adjusted for disease duration, saliva production increased significantly (p=0.029). Conclusions CTLA4-Ig treatment significantly reduces glandular inflammation in pSS, induces several celluar changes and increases saliva production. Remarkably, this increase in saliva production is significantly influenced by disease duration.

Mucin-producing adenocarcinoma arising in an atrial myxoma

We describe the unique autopsy findings of a patient who died of a metastasizing giant right atrial adenocarcinoma containing few areas of typical myxoma. That no mucin-producing extracardiac tumor was detected pointed to the atrial adenocarcinoma as being the primary. We hypothesize that the adenocarcinoma may have developed from coexistent bland glandular structures within the myxoma.

Myoepithelioma of the cerebellopontine angle: a previously not documented benign salivary gland-type neoplasm within the cranium

Myoepithelioma is a dimorphic neoplasm with contractile-epithelial phenotype, originally interpreted as deriving from, but not actually restricted to the salivary glands. As a novel addition to the list of exquisitely rare intracranial salivary gland-type tumors and tumor-like lesions, we report on an example of myoepithelioma encountered in the left cerebellopontine angle of a 32-year-old male. Clinically presenting with ataxia and dizziness, this extraaxial mass of 4 × 3.5 × 3 cm was surgically resected, and the patient is alive 6 years postoperatively. Histologically, the tumor exhibited a continuum ranging from compact fascicles of spindle cells to epithelial nests and trabeculae partitioned by hyalinized septa, while lacking tubular differentiation. Regardless of architectural variations, there was robust immunoexpression of S100 protein, smooth muscle actin, GFAP, cytokeratin, and vimentin. Cytologic atypia tended to be modest throughout, and the MIB1 labeling index averaged less than 1%. Fluorescent in situ hybridization indicated no rearrangement of the EWSR1 locus. We interpret these results to suggest that myoepithelioma of the posterior fossa - along with related salivary epithelial tumors in this ostensibly incongruous locale - may possibly represent analogous neoplasms to their orthotopic counterparts, ones arising within aberrant salivary anlagen. The presence of the latter lends itself to being mechanistically accounted for by either postulating placodal remnants in the wake of branchial arch development, or linking them to exocrine glandular nests within endodermal cysts. Alternatively, myoepithelioma at this site could be regarded as a non tissue-specific lesion similar to its relatives ubiquitously occurring in the soft parts.

Collision tumor affecting the paranasal sinuses of a geriatric donkey

Tumours of the paranasal sinuses are relatively uncommon in the horse. A collision tumour occurs when 2 separate tumour types arise in close proximity to each other and encroach on one another. This report describes the presence of neoplasia comprising glandular tissue and spindle cells growing concurrently in the frontal and caudal maxillary sinus of a geriatric donkey. As far as the authors are aware, this is the first description of a possible collision tumour in an equid.

Can widely used cell type markers predict the suitability of immortalized or primary mammary epithelial cell models?

BACKGROUND Mammary cell cultures are convenient tools for in vitro studies of mammary gland biology. However, the heterogeneity of mammary cell types, e.g., glandular milk secretory epithelial or myoepithelial cells, often complicates the interpretation of cell-based data. The present study was undertaken to determine the relevance of bovine primary mammary epithelial cells isolated from American Holstein (bMECUS) or Swiss Holstein-Friesian (bMECCH) cows, and of primary bovine mammary alveolar epithelial cells stably transfected with simian virus-40 (SV-40) large T-antigen (MAC-T) for in vitro analyses. This was evaluated by testing their expression pattern of cytokeratin (CK) 7, 18, 19, vimentin, and α-smooth muscle actin (α-SMA). RESULTS The expression of the listed markers was assessed using real-time quantitative PCR, flow cytometry and immunofluorescence microscopy. Characteristic markers of the mesenchymal (vimentin), myoepithelial (α-SMA) and glandular secretory cells (CKs) showed differential expression among the studied cell cultures, partly depending on the analytical method used. The relative mRNA expression of vimentin, CK7 and CK19, respectively, was lower (P < 0.05) in immortalized than in primary mammary cell cultures. The stain index (based on flow cytometry) of CK7 and CK19 protein was lower (P < 0.05) in MAC-T than in bMECs, while the expression of α-SMA and CK18 showed an inverse pattern. Immunofluorescence microscopy analysis mostly confirmed the mRNA data, while partly disagreed with flow cytometry data (e.g., vimentin level in MAC-T). The differential expression of CK7 and CK19 allowed discriminating between immortal and primary mammary cultures. CONCLUSIONS The expression of the selected widely used cell type markers in primary and immortalized MEC cells did not allow a clear preference between these two cell models for in vitro analyses studying aspects of milk composition. All tested cell models exhibited to a variable degree epithelial and mesenchymal features. Thus, based on their characterization with widely used cell markers, none of these cultures represent an unequivocal alveolar mammary epithelial cell model. For choosing the appropriate in vitro model additional properties such as the expression profile of specific proteins of interest (e.g., transporter proteins) should equally be taken into account.

Positron emission mammography in the diagnosis of breast cancer. Is maximum PEM uptake value a valuable threshold for malignant breast cancer detection?

AIM To evaluate the diagnostic value (sensitivity, specificity) of positron emission mammography (PEM) in a single site non-interventional study using the maximum PEM uptake value (PUVmax). PATIENTS, METHODS In a singlesite, non-interventional study, 108 patients (107 women, 1 man) with a total of 151 suspected lesions were scanned with a PEM Flex Solo II (Naviscan) at 90 min p.i. with 3.5 MBq 18F-FDG per kg of body weight. In this ROI(region of interest)-based analysis, maximum PEM uptake value (PUV) was determined in lesions, tumours (PUVmaxtumour), benign lesions (PUVmaxnormal breast) and also in healthy tissues on the contralateral side (PUVmaxcontralateral breast). These values were compared and contrasted. In addition, the ratios of PUVmaxtumour / PUVmaxcontralateral breast and PUVmaxnormal breast / PUVmaxcontralateral breast were compared. The image data were interpreted independently by two experienced nuclear medicine physicians and compared with histology in cases of suspected carcinoma. RESULTS Based on a criteria of PUV>1.9, 31 out of 151 lesions in the patient cohort were found to be malignant (21%). A mean PUVmaxtumour of 3.78 ± 2.47 was identified in malignant tumours, while a mean PUVmaxnormal breast of 1.17 ± 0.37 was reported in the glandular tissue of the healthy breast, with the difference being statistically significant (p < 0.001). Similarly, the mean ratio between tumour and healthy glandular tissue in breast cancer patients (3.15 ± 1.58) was found to be significantly higher than the ratio for benign lesions (1.17 ± 0.41, p < 0.001). CONCLUSION PEM is capable of differentiating breast tumours from benign lesions with 100% sensitivity along with a high specificity of 96%, when a threshold of PUVmax >1.9 is applied.