Interferon-γ (IFN-γ) has been used to control cancers in clinical treatment. However, an increasing number of reports have suggested that in some cases effectiveness declines after a long treatment period, the reason being unclear. We have reported previously that long-term IFN-γ treatment induces malignant transformation of healthy lactating bovine mammary epithelial cells (BMECs) in vitro. In this study, we investigated the mechanisms underlying the malignant proliferation of BMECs under IFN-γ treatment. The primary BMECs used in this study were stimulated by IFN-γ (10 ng/mL) for a long term to promote malignancy. We observed that IFN-γ could promote malignant cell proliferation, increase the expression of cyclin D1/cyclin-dependent kinase 4 (CDK4), decrease the expression of p21, and upregulate the expression of cellular-abelsongene (c-Abl) and histone deacetylase 2 (HDAC2). The HDAC2 inhibitor, valproate (VPA) and the c-Abl inhibitor, imatinib, lowered the expression level of cyclin D1/CDK4, and increased the expression level of p21, leading to an inhibitory effect on IFN-γ-induced malignant cell growth. When c-Abl was downregulated, the HDAC2 level was also decreased by promoted proteasome degradation. These data suggest that IFN-γ promotes the growth of malignant BMECs through the c-Abl/HDAC2 signaling pathway. Our findings suggest that long-term application of IFN-γ may be closely associated with the promotion of cell growth and even the carcinogenesis of breast cancer.
Animals ; Carcinogenesis/pathology* ; Cattle ; Cell Cycle Proteins/metabolism* ; Cell Proliferation/drug effects* ; Cell Transformation, Neoplastic/pathology* ; Cells, Cultured ; Epithelial Cells/pathology* ; Female ; Histone Deacetylase 2/metabolism* ; Imatinib Mesylate/pharmacology* ; Interferon-gamma/pharmacology* ; Mammary Glands, Animal/pathology* ; Mammary Neoplasms, Experimental/pathology* ; Proto-Oncogene Proteins c-abl/metabolism* ; Signal Transduction ; Valproic Acid/pharmacology*

Metastasis is the leading cause of death in breast cancer patients. However, the mechanisms underlying metastasis are not well understood and there is no effective treatment in the clinic. Here, we demonstrate that in MMTV-PyMT, a highly malignant spontaneous breast tumor model, IL-25 (also called IL-17E) was expressed by tumor-infiltrating CD4 T cells and macrophages. An IL-25 neutralization antibody, while not affecting primary tumor growth, substantially reduced lung metastasis. Inhibition of IL-25 resulted in decreased type 2 T cells and macrophages in the primary tumor microenvironments, both reported to enhance breast tumor invasion and subsequent metastasis to the lung. Taken together, our data suggest IL-25 blockade as a novel treatment for metastatic breast tumor.
Animals ; Antibodies, Neoplasm ; pharmacology ; Antibodies, Neutralizing ; pharmacology ; Breast Neoplasms ; drug therapy ; genetics ; immunology ; CD4-Positive T-Lymphocytes ; immunology ; pathology ; Female ; Humans ; Interleukin-17 ; antagonists & inhibitors ; genetics ; immunology ; Interleukins ; antagonists & inhibitors ; genetics ; immunology ; Macrophages ; immunology ; pathology ; Mammary Neoplasms, Animal ; drug therapy ; genetics ; immunology ; Mice ; Neoplasm Metastasis ; Tumor Microenvironment ; drug effects ; genetics ; immunology

During normal postnatal mammary gland development and adult remodeling related to the menstrual cycle, pregnancy, and lactation, ovarian hormones and peptide growth factors contribute to the delineation of a definite epithelial cell identity. This identity is maintained during cell replication in a heritable but DNA-independent manner. The preservation of cell identity is fundamental, especially when cells must undergo changes in response to intrinsic and extrinsic signals. The maintenance proteins, which are required for cell identity preservation, act epigenetically by regulating gene expression through DNA methylation, histone modification, and chromatin remodeling. Among the maintenance proteins, the Trithorax (TrxG) and Polycomb (PcG) group proteins are the best characterized. In this review, we summarize the structures and activities of the TrxG and PcG complexes and describe their pivotal roles in nuclear estrogen receptor activity. In addition, we provide evidence that perturbations in these epigenetic regulators are involved in disrupting epithelial cell identity, mammary gland remodeling, and breast cancer initiation.
Animals ; Breast Neoplasms ; genetics ; pathology ; physiopathology ; Cell Transformation, Neoplastic ; Chromatin ; genetics ; metabolism ; Epigenesis, Genetic ; physiology ; Epithelial Cells ; cytology ; Female ; Gene Expression Profiling ; Gene Expression Regulation, Developmental ; Histone-Lysine N-Methyltransferase ; Humans ; Mammary Glands, Animal ; cytology ; growth & development ; Mammary Glands, Human ; cytology ; growth & development ; Myeloid-Lymphoid Leukemia Protein ; genetics ; physiology ; Polycomb-Group Proteins ; genetics ; physiology ; Receptors, Estrogen ; metabolism

OBJECTIVETo explore the effect of ricin temperature response gel on breast cancer and its regulatory effect on immune function in rats.

METHODSRicin was purified by chromatography and identified by immunoblotting. The rat subcutaneously transplanted breast cancer model was established. Forty model rats with a tumor diameter of about 3.0 cm were subjected to the study. They were randomized into four groups equally: the model group and three treated groups (blank gel, ricin, ricin-gel) were administered with blank gel, ricin, and ricin temperature response gel via percutaneous intratumor injection, respectively. The tumor was isolated 10 days later for the estimation of tumor inhibition rate (TIR) by weighing, pathologic examination, and detection of tumor apoptosis-associated genes bcl-2 and bax with semiquantitative RT-PCR. Also, peripheral blood was obtained to test T-lymphocyte subsets, the killing function of lymphocytes, and the contents of tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2). The outcomes were compared between groups.

RESULTSThe TIR in the ricin-gel group was 61.8%, with the pathologic examination showing extensive tumor tissue necrosis. Compared with the model group, after ricin temperature response gel treatment, bcl-2 expression was down-regulated, bax expression was up-regulated, CD4+ lymphocytes and CD4+/CD8+ ratio in peripheral blood were increased, the killing function of lymphocytes was enhanced, and the contents of TNF-α and IL-2 were elevated (P < 0.05 or P < 0.01).

CONCLUSIONIntratumor injection of ricin temperature-responsive gel showed significant antitumor effect on breast cancer and could enhance the immune function in the tumor-bearing rat.

Animals ; Antineoplastic Agents ; administration & dosage ; Apoptosis ; drug effects ; CD4-CD8 Ratio ; Disease Models, Animal ; Female ; Gels ; therapeutic use ; Immunohistochemistry ; Immunomodulation ; drug effects ; Injections, Intralesional ; Interleukin-2 ; immunology ; metabolism ; Mammary Neoplasms, Experimental ; drug therapy ; immunology ; pathology ; Random Allocation ; Rats ; Rats, Wistar ; Ricin ; administration & dosage ; Sensitivity and Specificity ; Temperature ; Tumor Necrosis Factor-alpha ; immunology ; metabolism

OBJECTIVETo study and evaluate the effect of Sangu Decoction (SGD, ) on the bone destruction due to mammary cancer metastasis.

METHODSMetastasis rat mammary tumor-1 cells were transplanted into the left hind limb tibia of SD rats to establish the bone metastasis of the mammary cancer model. The modeled rats were treated with SGD for observing its effect on rats' pain behavior, including 50% paw withdrawal threshold (50% PWT) after von Frey fiber stimulation, burden difference of bilateral feet, and thermal withdrawal latency (TWL), with zoledronic acid as the positive control. Moreover, the damage in the tibia sample of rats was scored by an iconographic method, and the bone mineral density (BMD) as well as the bone mineral content (BMC) were estimated.

RESULTSThe model established showed characteristics of mixed metastasis, revealing the manifestations of tumor development, bone destruction, cancerous pain, etc. In the SGD-treated group, 50% PWT was prolonged (8.13 ± 4.76 vs. 2.30 ± 2.19), and TWL was longer (3.48 ± 0.62 s vs. 2.89 ± 0.26 s) than those in the control group, respectively (P<0.05 or P<0.01). Iconographic scoring also showed improvement of BMD (0.134 ± 0.009 vs. 0.120 ± 0.007, P<0.01) and an elevating trend of BMC in the SGD-treated group.

CONCLUSIONSGD could effectively alleviate the cancerous pain of bone metastasis and mitigate the metastasis that cause osteolytic destruction of bone.

Animals ; Bone Density ; drug effects ; Bone Neoplasms ; drug therapy ; physiopathology ; secondary ; Bone and Bones ; drug effects ; pathology ; physiopathology ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Mammary Neoplasms, Animal ; pathology ; Rats ; Rats, Sprague-Dawley ; Reaction Time ; drug effects

The aim of this study was to construct a mammary gland-specific expressional vector pBC1-hLF-Neo for Human Lactoferrin (hLF) gene and then investigate its expression in the mammary gland epithelium cells. The constructed vector contained the 6.2 kb long 5' flank regulation region including promoter, other elements and the 7.1 kb long 3' flank regulation region including transcriptional ending signal of a goat's beta-casein gene. A cassette of Neo gene was also inserted into the vector which gave a total length of 26.736 kb identified by restriction fragment analysis and partial DNA sequencing. The results revealed that the structure of the final constructed vector accords with the designed plasmid map. In order to analyze the bioactivity of the vector, we transfected the lined vector DNA into the dairy goat's mammary gland epithelium cells and C127 cells of a mouse's mammary epithelium by Lipofectamine. After selection with G418 for 8-10 days, G418-risistant clones were obtained. PCR analysis demonstrated that hLF gene cassette had been integrated into the genomic DNA of G418-risistant clones. After proliferation culture, the two kinds of transgenic cells were cultured in serum-free DMEM-F12 medium with prolactin, insulin and hydrocortisone- a medium capable of inducing recombinant hLF expression. RT-PCR, Western blotting and anti-bacteria bioactivity experiments demonstrated that the constructed mammary gland specific vector pBC1-hLF-Neo possessed the desirable bioactivity to efficiently express and could secrete hLF in both mammary gland cells and have the effect of E. coli proliferation inhibition. Paramount to everything, this study laid a firm foundation for preparing the hLF gene transgenic goat fetal-derived fibroblast cells.
Animals ; Base Sequence ; Breast Neoplasms ; metabolism ; pathology ; Caseins ; genetics ; Cell Line, Tumor ; DNA, Complementary ; biosynthesis ; genetics ; Epithelial Cells ; metabolism ; Female ; Genetic Vectors ; genetics ; Goats ; Humans ; Lactoferrin ; biosynthesis ; genetics ; Mammary Glands, Animal ; cytology ; metabolism ; Mice ; Molecular Sequence Data ; Mutagenesis, Insertional ; Promoter Regions, Genetic ; genetics

OBJECTIVETo establish a whole-body visualization model of breast cancer with high hepatic metastatic potential in nude mice and observe the development and metastasis of breast cancer by real-time imaging.

METHODSpEGFP-N1 plasmid was transfected into human breast cancer cell line MDA-MB-231 to obtain pEGFP-MDA-MB-231 cells that emitted fluorescence. pEGFP-MDA-MB-231 cells were inoculated orthotopically in BALB/C nude mice and cultured in vivo through serial passage, thereby establishing the mouse model bearing tumors with high hepatic metastasis potential. The fluorescence emitted from the tumors was quantitatively detected and imaged with a fluorescence stereo microscope for real-time visualization of the tumor growth and metastasis.

RESULTSThe transfected breast cancer cells stably and efficiently expressed EGFP. After inoculation of the transfected cells in nude mice, 20% of the first-generation cells showed hepatic metastasis, and the rate increased to 80% among the second-generation and up to 100% among the third-generation cells. The reliability of this visualization model was validated with conventional pathological methods.

CONCLUSIONThe whole-body visualization model bearing breast cancer with high hepatic metastasis potential provides a reliable means for studying the mechanisms of hepatic tumor metastasis, and can be instrumental in the exploration of novel means for breast cancer treatment.

Animals ; Breast Neoplasms ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Liver Neoplasms ; genetics ; metabolism ; secondary ; Mammary Neoplasms, Experimental ; genetics ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Microscopy, Fluorescence ; Neoplasm Transplantation ; Transplantation, Heterologous

A fibroadenoma was diagnosed in the left udder of a 3-month-old female Chios lamb. No recurrence was observed after surgery. Grossly, the tumor had a whitishgray lobular appearance, and the lobules were interlaced with thin septa. Microscopically, the tumor was composed of proliferating fibroepithelial tissue, including differentiated ducts lined by whorls and interlacing bundles of abundant loose fibrovascular stroma. Immunohistochemistry revealed the ductal epithelium to be positive for pancytokeratin (AE1/AE3) and loose fibrovascular stroma was positive for vimentin and basal cells covering the ductal epithelium of alpha-smooth-muscle actin. Immunostaining for the estrogen and progesterone receptors was negative. A diagnosis of mammary fibroadenoma was made based on the histological and immunohistochemical findings.
Animals ; Female ; Fibroadenoma/pathology/*veterinary ; Keratins/metabolism ; Mammary Glands, Animal/*pathology ; Mammary Neoplasms, Animal/*pathology ; Sheep ; Sheep Diseases/*pathology ; Vimentin/metabolism

Axillary disorders originate from an axillary lymph node, subcutaneous fat layer, accessory breast, nerve, vessel and muscle. The most common causes of a palpable axillary mass are a lymph node pathology containing a benign axillary lymphadenopathy, and malignant lymph nodes such as a metastatic lymphadenopathy from breast cancer and a malignant lymphoma. For the detection of masses in the axilla, mammography and sonography are the imaging modalities of choice. We present a spectrum of various axillary masses with correlative radiological imaging and pathological findings in this pictorial essay. Knowledge of the radiological findings of various axillary disorders is useful for a differential diagnosis and for preventing unnecessary invasive procedures.
Animals ; Axilla ; Breast Neoplasms ; Breast* ; Diagnosis, Differential ; Lymph Nodes ; Lymphatic Diseases ; Lymphatic Metastasis ; Lymphatic System ; Lymphoma ; Mammary Neoplasms, Animal ; Mammography ; Neoplasm Metastasis* ; Pathology ; Radiography ; Subcutaneous Fat ; Ultrasonography

Animals ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Humans ; Immunohistochemistry ; Male ; Mammary Neoplasms, Experimental ; chemistry ; pathology ; Mice ; Mitotic Index ; Neoplasm Transplantation ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Transplantation, Heterologous