The formation of HER2 homodimers plays an important role in breast cancer aggressiveness and progression; however, little is known about its localization. We have studied the intra- and intercellular variation of HER2 at the single-molecule level in intact SKBR3 breast cancer cells. Whole cells were visualized in hydrated state with correlative fluorescence microscopy and environmental scanning...

Purpose: ZD1839 is a tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR) that has shown clinical activity against EGFR-expressing tumors. Our aim was to explore the effects of ZD1839 in breast cancer cell lines expressing different levels of EGFR and the closely related HER2 receptor. Experimental Design: We studied the growth-inhibitory effects of ZD1839 in a series of bre...

Erlotinib (Tarceva), is an orally available, reversible inhibitor of epidermal growth factor receptor (EGFR; HER1) that exhibits inhibitory activity on purified HER2 kinase at much higher concentrations. Despite the minimal activity on purified protein in vitro, in vivo studies show that erlotinib inhibits the growth of HER2-driven systems effectively. Several hypotheses have been put forward t...

Aim: Receptor status study in breast cancer is uncommon in rural population in India. Our aim in this study is to evaluate the expression of hormone receptors Estrogen receptor (ER), Progesterone receptor (PR) along with Human Epidermal growth receptor 2 (HER2/neu) expression in breast cancer cells and distribution with regards to age, menopausal status, tumor size, histological grading and lym...

background: breast cancer is the most common cancer in women, containing approximately one third of all illnesses in women. assessment of molecular markers is valuable in predicting the outcome of disease and decision making for optimal treatment. the purpose of this study was to determine the relationship between estrogen and progesterone receptors with her-2, ki67, p53, and clinicopathologica...

PURPOSE The aim of this work is to determine the possible relationship between the different profiles of molecular expression of hormone receptors and Her-2÷neu receptors to clinical and histopathological known prognostic variables for breast cancer. MATERIALS AND METHODS A total of 110 breast carcinoma tumor samples were included. In this study 4 groups or immunohistochemical profiles were d...

Accumulating evidence indicates a functional crosstalk between the HER2 (ErbB2) tyrosine kinase and the TGF-β signaling mediated by its serine/threonine kinase receptors. In HER2-overexpressing breast cancer, this crosstalk results in increased cancer cell proliferation, survival and invasion, accelerated cancer progression and metastasis in animal models, and resistance to chemotherapy and HER...

Targeting HER2 for the treatment of HER2-positive breast cancers is now a validated treatment paradigm. However, evidence suggests that this family of receptors may have important roles outside of the realm of HER2 amplification. There is considerable interest in the development of biomarkers to identify such breast cancers.

The prognosis of hormone receptor (HR)-positive early breast cancer (eBC) may vary according to different factors. Human Epidermal Growth Factor Receptor-2 (HER2) is one them. HER2-low population, defined as HER2 1+ or 2+ with negative fluorescent in situ hybridization (FISH), seems have a than the HER2-0. We aimed explore impact HER2-negative status on risk recurrence PAM50 score. conducted re...

Herceptin (trastuzumab) is used in patients with breast cancer who have HER2 (ErbB2)-positive tumours. However, its mechanisms of action and how acquired resistance to Herceptin occurs are still poorly understood. It was previously thought that the anti-HER2 monoclonal antibody Herceptin inhibits HER2 signalling, but recent studies have shown that Herceptin does not decrease HER2 phosphorylatio...