Previous studies have shown that the development of mam mary alveolar lesions (MALs) precedes the emergence of overt mammary tumors in high-breast-cancer strains of mice, such as Rill, that are infected with exogenous murine mammary tumor virus. We cultured MAL-containing whole mammary glands from 7-month-old nulliparous Rill mice for 8 days (Days 0 to 8) in a serum-free medium that contained i...

Loss of Tsc1/Tsc2 results in excess cell growth that eventually forms hamartoma in multiple organs. Our study using a mouse model with Tsc1 conditionally knockout in mammary epithelium showed that Tsc1 deficiency impaired mammary development. Phosphorylated S6 was up-regulated in Tsc1(-/-) mammary epithelium, which could be reversed by rapamycin, suggesting that mTORC1 was hyperactivated in Tsc...

We have studied the role of the cyclin-dependent kinase (Cdk) inhibitor p27(Kip1) in postnatal mammary gland morphogenesis. Based on its ability to negatively regulate cyclin/Cdk function, loss of p27 may result in unrestrained cellular proliferation. However, recent evidence about the stabilizing effect of p27 on cyclin D1-Cdk4 complexes suggests that p27 deficiency might recapitulate the hypo...

HOSHIAT, H., TAKAHASHI, K., FURUHASHI, N., WADA, Y., UEHARA, S. and SUZUKI, M. Cytoplasmic Estrogen Receptors of Rat Mammary Glands during Pregnancy and Puerperium. Tohoku J. exp. Med., 1982, 136 (2), 195-202 The variation of cytoplasmic estrogen receptor in the mammary gland during pregnancy and puerperium was studied to determine the role of estrogens in the mechanism of lactation. Cytosol es...

Perinatal exposure to bisphenol A (BPA) has been shown to cause aberrant mammary gland morphogenesis and mammary neoplastic transformation. Yet, the underlying mechanism is poorly understood. We tested the hypothesis that mammary glands exposed to BPA during a susceptible window may lead to its susceptibility to tumorigenesis through a stem cell-mediated mechanism. We exposed 21-day-old Balb/c ...

Deregulated expression of several cell cycle regulatory genes has been demonstrated to be associated with cancer. In particular, a strong correlation has been established between inappropriate cyclin E expression and human breast cancer. To determine the ability of cyclin E to play a causative role in mammary tumorigenesis, regulatory sequences from the ovine beta-lactoglobulin gene were utiliz...

Early studies of the mammary gland and its innervation led to the belief, at least in some quarters, that mammary activity is under the control of the nervous system.6 With the development of endocrinology, however, growth and function of the mammary apparatus were found to be determined by secretions of the ovaries and hypophysis. In a number of species mammary development identical with that ...

PURPOSE The objective of the present study was to delineate the efficacy of tetrathiomolybdate (TM), a novel antiangiogenic anticancer agent, as a chemopreventative agent. EXPERIMENTAL DESIGN Nulliparous Her2/neu transgenic mice were treated with water or TM for 180 days and observed for tumor development during treatment and for 180 days after treatment. Mammary gland composition and archite...