Alterations in apoptosis and associated mechanisms during mammary tumor progression were investigated in transgenic mice expressing the SV40 large T antigen (T(AG)) driven by the rat prostatic steroid-binding protein C3(1) 5'-flanking region. Apoptosis levels, assessed by in situ end labeling, were low in normal mammary epithelial cells, highest in atypical hyperplasias (preneoplastic lesions),...

Prognosis of metastatic breast cancer is very poor which urges the necessity to develop novel potential drug candidates. We assessed two compounds with tri-aryl structures (A and B) for their potency to reduce primary breast tumor growth and lung metastasis in 4T1 mice model. MTT assay, 4T1 mammary mouse model and immunohistochemistry experiments were used in this study. In vitro results exhibi...

Infiltration of immune cells, specifically macrophages, into the tumor microenvironment has been linked to increased mammary tumor formation and progression. Activation of growth factor receptor signaling pathways within mammary epithelial cells, such as the fibroblast growth factor receptor 1 (FGFR1) pathway, induces recruitment of macrophages to the mammary epithelium. These macrophages promo...

The effects of bilateral adrenalectomy or estradiol benzoate treatment were observed on growth of 7,12-dimethylbenz(a)-anthracene-induced mammary tumors during postpartum lactation. In the control and estradiol benzoate-treated postpartum lactating rats, the mammary tumors decreased approximately 40% in size by Day 5 postpartum and continued to regress to 50% of their average original diameter ...

Estrogen acts as a complete mammary carcinogen in ACI rats. Prevention studies in this model allowed us to identify agents that are effective against estrogen-induced mammary carcinogenesis. In this study, we investigated efficacy of dietary berries and ellagic acid to reduce estrogen-mediated mammary tumorigenesis. Female ACI rats (8-9 wk) were fed either AIN-93M diet (n = 25) or diet suppleme...

Cancer is associated with immune dysfunction characterized by the presence of proinflammatory and immunosuppressive cells and factors that contribute to tumor growth and progression. Here we show that mammary tumor growth is associated with defects in hematopoiesis, leading to myeloproliferative-like disease (leukemoid reaction), anemia, and disruption of the bone marrow stem/progenitor compart...

The Breast cancer 1, early onset gene (BRCA1) is known to be significantly associated with human familial breast cancer and is identified to play an important role in canine mammary tumors. Here, genetic variations in the coding region and DNA methylation in the 5' flanking region of BRCA1 in canine mammary tumor samples, 15 each of benign and malignant against 10 normal canine mammary tissue s...

Using a syngeneic p53-null mouse mammary gland tumor model that closely mimics human breast cancer, we have identified, by limiting dilution transplantation and in vitro mammosphere assay, a Lin CD29CD24 subpopulation of tumor-initiating cells. Upon subsequent transplantation, this subpopulation generated heterogeneous tumors that displayed properties similar to the primary tumor. Analysis of b...