c-erbB-2/HER-2/neu (phospho-specific) Antibody Staining Protocol for Immunohistochemistry

Description: c-erbB-2 (HER-2/neu) is a 185 kDa receptor tyrosine kinase belonging to the epidermal growth factor receptor family, which also includes EGFR (HER-1), c-erbB-3 (HER-3), and c-erbB-4 (HER-4). Amplification of the HER-2 gene with overexpression of the protein occurs in 20-30% of breast cancers, and tumor progression in mammary cancer is associated with elevated levels of tyrosine-phosphorylated neu and erbB-3. Tyr is the phosphorylation site that is most tightly linked to oncogenic transformation and coupling to the ras/MAP kinase signaling pathway. Cases of invasive breast carcinoma with the phosphorylated receptor have displayed aggressive clinicopathological features and adverse prognoses. Activation of HER-2 is frequent in ductal carcinoma in situ suggesting that HER-2 signaling plays a critical role in the early stages of breast tumorigenesis.