A 15 year old female African lion (Panthera leo) was necropsied after its sudden death. The necropsy showed a mammary gland lesion measuring 10 cm in diameter and numerous white nodules with variable size in the liver, spleen, uterus, lungs and the heart. The histopathological examination showed that the neoplastic formation in the mammary region was a simple tubular carcinoma with metastases on the other organs. Upon immunohistochemical examination, the neoplastic cells expressed cytokeratins while the stroma of the tumour expressed vimentin. The proliferation index Ki-67 was moderate. Based on the macroscopic, histopathological and immunohistochemical findings, the neoplasia was diagnosed as a simple tubular mammary carcinoma.
Despina V. Pupaki, Dessislava Ankova, Veselin P. Vasilev and Pavel I. Rashev
The mammary gland is unique in its development because most of its branching occurs in adolescent rather than in prenatal development. During early pregnancy extensive ductal side branching occurs while during the second half, secretory lobuloalveolar units are formed within the mammary gland. As modulators of the extracellular matrix, matrix metalloproteinases (MMPs) are the major enzymes taking part in the development of the gland. The activity of MMP-2 and MMP-9 has mostly been associated with tumor progression, while their participation in the physiological development of the mammary gland is not well characterized. In the present study the cell-specific localization of MMP-2 and MMP-9 in the developing dog mammary gland during pregnancy was investigated. In the early stages, both gelatinases were present, being located mostly in the epithelium of the ducts and less so in the surrounding stroma. After the formation of alveoli, MMP-2 was still present but MMP-9 was absent from the glandular epithelium and the stroma, being present only in the epithelium of the larger ducts. The results show that most likely, both gelatinases take part in ductal branching during early pregnancy, but only MMP-2 is associated with the differentiated stage of lactation.
The bovine mammary gland is a special gland characterized by high secretory activity. During lactation the cellular and fibrous components of the interstitial tissue septa are exposed to store accumulated secretory products. The aim of this study was to find and study the cells in the stroma of the bovine lactating mammary gland. For this purpose, the immunohistochemical methods and antibodies against the smooth muscle actin, vimentin, and desmin were used. The myoepithelial cells (MEC) which stained with smooth muscle actin (SMA), were found supporting the secretory units and the intralobular ducts. Coexpression of the SMA and desmin were found in the smooth muscle cells of the blood vessels. The fibroblasts (myofibroblasts) and free cells positive to vimentin were located in the connective tissue septa. The results of this study on the mammary glands indicated that smooth muscle cells (SMC) were altered in the lactating mammary gland, with additional cells such as fibroblasts (myofibroblasts) participated in the storage and after milk let-down they allowed the mammary glands to return to their original state.
Gustavo A. Roa López, Jhon Jairo Suárez, Paola Barato and Noel Verján García
Epstein–Barr virus (EBV) is a γ-herpesvirus associated with various neoplasms in humans and is a probable aetiological agent in breast cancer; however, a causal relationship has not yet been established. Because of the epidemiological and clinicopathological similarities between breast cancer and canine mammary tumours, dogs have been proposed as a valid model for breast cancer.
Material and Methods
A total of 47 canine mammary gland tumour tissues were processed by routine histopathological technique with haematoxylin-eosin staining and classified according to the type of neoplasm. DNA was extracted from paraffin-embedded tissues and the EBNA-1 gene and the BamHI-W region specific for EBV were evaluated by nested PCR.
The histopathological evaluation revealed 2 benign neoplasms, and many carcinomas: 2 in situ, 9 simple, 3 solid, 10 complex, and 21 mixed. One sample was positive for the EBNA-1 gene, while all were negative for the BamHI-W region.
No association was found between EBV and mammary tumours in dogs. However, here we report for the first time the presence of an EBV gene sequence in a canine mammary tumour. It is likely that detection of EBV might be affected by the quality and quantity of DNA extracted from paraffin-embedded tissues. Additional studies are necessary to establish any association of EBV with mammary gland cancer in humans and in dogs, which could eventually lead to better public health prevention and control.
Katarzyna Łosiewicz, Małgorzata Chmielewska-Krzesińska, Piotr Socha, Anna Jakimiuk and Krzysztof Wąsowicz
The expression of miRNA-21, miRNA-10b, and miRNA-34a in malignant and benign tumours and non-neoplastic lesions in canine mammary gland, using real-time PCR with TaqMan probes was determined. The expression in normal tissues was compared to neoplastic and non-neoplastic lesions using one-way ANOVA test. Significant changes in miRNA expression in neoplastic tissues, as compared to normal ones, were demonstrated. In all neoplastic tissues, the miRNA-21 expression increased while in non-neoplastic lesions slightly decreased in comparison to normal ones. MiRNA-10b expression in malignant and benign tumours increased in comparison to normal tissues and non-neoplastic lesions. MiRNA-34a expression profile in neoplastic and non-neoplastic tissues differed from other examined miRNAs (miRNA-21 and miRNA-10b). In all samples miRNA-34a expression level decreased in comparison to normal tissues.
Hannaneh Golshahi, Abbas Tavasoly, Annahita Rezaie and Mohammad Farhadi
Immunohistochemical expression of urokinase plasminogen activator (uPA) was studied in 37 canine malignant mammary tumours to define the relationship between their histopathological type and grade. In 29 (78.4%) cases, expression of uPA by neoplastic cells was more than 10% and in 34 samples (91.9%) uPA expression by stromal cells (fibroblasts) was more than 10%. The uPA was expressed in epithelial and myoepithelial cells of carcinomas and carcinosarcomas and mesenchymal population of carcinosarcoma, chondrosarcoma, and carcinomas arising in benign tumours. The intensity and percentage of expression of uPA by stromal cells was associated with their histological grade (P < 0.05). However, no significant relationship was detected between uPA expression by neoplastic cells (epithelial, myoepithelial, and mesenchymal cell) and histological grade. Increased expression of uPA by tumour stroma was associated with poor prognostic factors. Stromal expression of uPA could be a prognostic indicator for canine mammary tumours.
Kibrom M. Alula, James H. Resau and Osman V. Patel
Alteration in gravitational load impacts homeorhetic response in rat dams which affects neonatal pup survival. However, the effects of hypergravity (HG) exposure on the abundance of apoptosis-associated proteins in mammary epithelial cells (MECs) have not been characterized. Therefore, we examined whether chronic exposure to HG from midpregnancy alters the abundance of proapoptotic proteins in MECs during the late pregnancy and early lactation. A group of pregnant Sprague Dawley rats were exposed to either HG (2g) or normo-gravity (1g: stationary control [SC]) from days 11 to 20 of gestation (G20). Another set of animals were investigated from day 11 of pregnancy through days 1 and 3 (P1 and P3, respectively) postpartum. Quantitative (pixels [px]/lobule) immunohistochemistry at G20 of Cleaved Caspase-3 (CC-3), Tumor Protein p53 (P53), and vitamin D receptor (VDR) revealed that all the three proteins were increased (p<0.01) in HG rats compared to SC animals. At P1, the HG group had twofold higher (p<0.001) expression of CC-3 relative to the SC group. Approximately, 50% (p<0.001) more VDR was detected in the HG cohorts than SC at P3. These results suggest that a shift in g-load upregulates the expression of key proapoptotic proteins during the pregnancy-to-lactation transition in the rat MECs.
The Concentration of Immunoglobulins A, G, and M in Cow Milk and Blood in Relation with Cow Seasonal Keeping and Pathogens Presence in the Udder
Recent studies show that immunoglobulins A, G, and M contribute significantly to the maintenance of udder health. Unfortunately, the concentration of immunoglobulins in cow milk during the middle period of lactation is low therefore the question of how to stimulate and maintain a sufficient level and spectrum of antibodies in the udder is topical. The aim of the present study was to evaluate the dynamics of the amount of immunoglobulins A, G, and M in cow milk and blood serum in relation with the cow seasonal keeping and presence of pathogens in the udder. The experimental part of the study was carried out on the dairy farm "Pērles", Valmiera region. Cows were kept in a cold loose housing system, grouped and fed differently depending on cow productivity and lactation period. Two times in the housing period and two times in the grazing period milk and blood were sampled from 16 dairy cows and examined for the concentration of immunoglobulins A, G, and M and for the presence of pathogens. Cows for the study were selected with the aim to analyze the milk obtained from clinically healthy udder quarters of cows of similar-age and productivity in the middle stage of lactation. It was determined that seasonal keeping of cows had significantly affected the concentration of immunoglobulins G and A in milk (p<0.001), and of immunoglobulins A, G, and M in blood serum (p<0.001). Some pathogenic bacteria species infecting the udder quarters had considerably influenced the values of immunoglobulins G, A, and M (p<0.05, p<0.001, and p<0.001, respectively) in blood serum. A wide variation amplitude of immunoglobulin G, A, and M concentration in milk and blood serum was observed, which indicates the important role of the individual factor of an animal in the formation of animal defence response.
Viktória Kissová, Zuzana Ševčíková, Viera Revajová, Róbert Herich and Mikuláš Levkut
The aim of the study was to evaluate the distribution and number of mast cells and eosinophils in rat mammary gland tumours induced by N-Nitroso-N-methylurea. The highest density of mast cells was found in cystic papillary adenocarcinomas of grade II. Eosinophils were detected only in the cystic papillary adenocarcinoma of grades I and II, in non-invasive cribriform adenocarcinoma and comedo-type carcinoma. Mast cell populations were observed perivascularly in the tumour stroma, in the host tumour interface, as well as in necrotic areas of neoplasms. Mast cells were observed to be intact according to their morphological changes, collectively referred to as degranulation. The obtained results indicate that mast cells and eosinophils play an important role in tumour micro-environment formation. The increased density of these cells in experimentally-induced rat mammary gland tumours suggests a poor prognosis in these cancers. Our results also confirmed that rat mammary gland tumours are good models for the study of breast cancers.
Composition, Properties and Nutritional Aspects of Milk Fat Globule Membrane - a Review
In the last few years, knowledge on the composition and properties of the milk fat globule membrane (MFGM) increased significantly. It is now recognized that the MFGM is highly complex in structure and composed of different protein and lipid components with specific technological and nutritional properties. As such, MFGM materials have been isolated and characterized as valuable ingredients for incorporation into new food products. However, MFGM are also sensitive to modification during isolation and processing, and care should be taken to standardize the composition and characteristics of the membrane to maintain its unique properties during application in food products.
The MFGM is subject to changes in composition and structure from the moment the fat globule leaves the mammary secretory cell. Upon milk harvesting and further milk handling, further changes to the MFGM take place. Depending on the type and degree of treatment, this may involve different physico-chemical interactions between various membrane components, the loss of membrane components and/or adsorption of components from the milk plasma. However, the effects appear to be variable and dependent on physiological (animal) factors, and much remains to be learned about the phenomena on a molecular level.