Multichromatic phenotyping of HER receptor coexpression in breast tumor tissue samples using flow cytometry--possibilities and limitations.

The prognostic significance of HER2 expression in human breast carcinomas is beyond dispute nowadays. The HER family of receptor tyrosine kinases comprises four members (HER1/ErbB1/EGFR, HER2/ErbB2, HER3/ErbB3, and HER4/ErbB4) that act in concert via transactivation and consequently compose a functional signaling unit. Besides HER2 overexpression, coexpression of other HER receptors has substantial impact on course of disease and potential therapeutic benefit.

Presence of HER4 associates with increased sensitivity to Herceptin in patients with metastatic breast cancer.

Introduction: HER2 overexpression, or rather HER2 gene amplification, is indicative for Herceptin therapy in both metastatic and pre-metastatic breast cancer patients. Patient's individual sensitivity to Herceptin treatment, however, varies enormously and spans from effectual responsiveness over acquired insensitivity to complete resistance from the outset. Thus no predictive information can be deduced from HER2 determination so that molecular biomarkers indicative for Herceptin sensitivity or resistance need to be identified.

Cytogenetic analysis of HER1/EGFR, HER2, HER3 and HER4 in 278 breast cancer patients.

Introduction: The HER (human EGFR related) family of receptor tyrosine kinases (HER1/EGFR (epidermal growth factor receptor)/c-erbB1, HER2/c-erbB2, HER3/c-erbB3 and HER4/c-erbB4) shares a high degree of structural and functional homology. It constitutes a complex network, coupling various extracellular ligands to intracellular signal transduction pathways resulting in receptor interaction and cross-activation. The most famous family member is HER2, which is a target in Herceptin therapy in metastatic status and also in adjuvant therapy of breast cancer in the event of dysregulation as a result of gene amplification and resulting protein overexpression.

Mercuric dichloride induces DNA damage in human salivary gland tissue cells and lymphocytes.

Amalgam is still one of the most frequently used dental filling materials. However, the possible adverse effects especially that of the mercuric component have led to continued controversy. Considering that mercury may be released from amalgam fillings into the oral cavity and also reach the circulating blood after absorption and resorption, it eventually may contribute to tumorigenesis in a variety of target cells.

Cytotoxic and genotoxic effects of resin monomers in human salivary gland tissue and lymphocytes as assessed by the single cell microgel electrophoresis (Comet) assay.

Malignant tumors of the three major pairs and the numerous minor salivary glands in humans are rare, and little is known about their various etiologies. Considering the fact that resin monomers from dental restorative materials are released into the saliva and diffuse into the tooth pulp or gingiva, mucosa, and salivary glands, this may potentially contribute to tumorigenesis. Resin monomers may also be reabsorbed and reach the circulating blood as well.