Levels of estrogen receptors alpha and beta in frontal cortex of patients with Alzheimer's disease: relationship to Mini-Mental State Examination scores.

Estrogen exerts beneficial effects on the brain throughout life. Studies demonstrate that estrogen is neuroprotective and that reduced brain estrogen activity may influence the clinical course of Alzheimer's disease (AD). Changes in levels of estrogen receptors have been detected in postmortem brain tissue of AD patients.

Role for HER2/neu and HER3 in fulvestrant-resistant breast cancer.

Tamoxifen resistance is common for estrogen receptor alpha (ERalpha) positive breast cancer. Second-line therapies include aromatase inhibitors or fulvestrant. We have shown previously that fulvestrant reversed 17beta-estradiol-induced tumor regression of tamoxifen-stimulated MCF-7 xenografts (MCF-7TAMLT) treated for >5 years with tamoxifen in athymic mice and paradoxically stimulated growth.

Development and therapeutic options for the treatment of raloxifene-stimulated breast cancer in athymic mice.

Purpose: Selective estrogen receptor modulators (SERM) are used for the treatment and prevention of breast cancer (tamoxifen) and osteoporosis (raloxifene). Mechanisms of tamoxifen-resistance in breast cancer are incompletely understood but current research is focused on crosstalk between growth factor receptors and the estrogen receptor alpha (ERalpha) pathway. There is increasing clinical use of raloxifene for the treatment of osteoporosis, but the widespread use of this SERM will have consequences for the treatment of breast cancer in raloxifene-exposed women.

Intrinsic mechanism of estradiol-induced apoptosis in breast cancer cells resistant to estrogen deprivation.

Background: We previously developed an estrogen receptor (ER)-positive breast cancer cell line (MCF-7:5C) that is resistant to long-term estrogen deprivation and undergoes rapid and complete apoptosis in the presence of physiologic concentrations of 17beta-estradiol. Here, we investigated the role of the mitochondrial apoptotic pathway in this process.

Methods: Apoptosis in MCF-7:5C cells treated with estradiol, fulvestrant, or vehicle (control) was investigated by annexin V-propidium iodide double staining and 4',6-diamidino-2-phenylindole (DAPI) staining.

Trastuzumab therapy for tamoxifen-stimulated endometrial cancer.

A novel in vivo model of tamoxifen-stimulated endometrial cancer was developed and the role of HER-2/neu investigated by using trastuzumab. Tamoxifen-stimulated tumors (ECC-1TAM) were growth stimulated by 17beta-estradiol (E2), tamoxifen, or raloxifene. Trastuzumab inhibited growth of E2-stimulated ECC-1E2 tumors by 50% and tamoxifen-stimulated ECC-1TAM tumors by 100%.

The consequences of exhaustive antiestrogen therapy in breast cancer: estrogen-induced tumor cell death.

Forty years ago, the endocrine treatment for breast cancer was a last resort at palliation before the disease overwhelmed the patient (1). Ovarian ablation was the treatment of choice for the premenopausal patient, whereas either adrenalectomy or, paradoxically, high-dose synthetic estrogen therapy were used for treatment in postmenopausal patients. A reduction or an excess of estrogen provoked objective responses in one out of three women.