Technical Articles

This article focuses on the molecular characteristics and signal transduction functions of human epidermal growth factor receptor 2 (HER2), systematically elaborating its molecular mechanism as a member of the epidermal growth factor receptor family in initiating downstream proliferation signaling pathways through receptor dimerization and tyrosine residue phosphorylation, analyzing the roles of two types of abnormalities—c-erbB-2 gene mutation, deletion, and amplification, as well as HER2 protein overexpression—in tumor occurrence and development, and exploring the differentiated therapeutic value of HER2 gene mutations in lung cancer versus HER2 protein amplification in breast cancer and gastric cancer.

Human epidermal growth factor receptor 2 (HER2) is a key marker for molecular typing of breast cancer. Accurate evaluation of its expression level plays a decisive role in treatment decisions. With the release of milestone studies such as DESTINY-Break04, the clinical value of HER2 low expression (IHC 1+or 2+/ISH -) breast cancer is increasingly prominent.