HER2 And HER3 Expression In Non-small-cell Lung Cancer And Correlation With Efficacy Of Gefitinib

Objective: To evaluate the correlation between HER2/HER3 expression and gefitinib efficacy in non-small-cell lung cancer (NSCLC). The epidermal growth factor receptor (EGFR) family includes the four distinct receptors: HER1(erbB1,EGFR),HER2(erbB2,neu),HER3(erbB3) and HER4(erbB4). A number of different ligands can active the HER by binding the extra-cellular domain and forming homodimers or heterodimers, then the tyrosine kinase (TK) signal pathways are activated, As a result, the activated HER will stimulate the development of tumor including proliferation, invasion, metastatasis and anti-apoptosis. Gefitinib is a selective EGFR tyrosine kinase inhibitor (EGFR-TKI), and completive with ATP, and it inhibitors the activity of TK of receptor in EGFR family. Gefitinib has been approved to use advanced NSCLC patients. The studies of gefitinib have illustrated that efficacy of gefitinib seems not to expressing status of EGFR; Mutation of EGFR seems to be pertinent to efficacy of gefitinib, but the function of mutation need to confirm. HER4 expression rate was much lower in most cancer tissue than that of non-cancer tissue; it may not have function in the development of cancer. Some pre-clinical studies have indicated that HER2 and HER3 expression may be pertinent to efficacy of Gefitinib. But we have not the accurate conclusion in clinical study.So, we inspected the HER2,HER3 expressing status in NSCLC patients, who took gefitinib. And we evaluated the correlation between HER2/HER3 expression and gefitinib efficacy in NSCLC.Methods:...