HER2, or Human Epidermal growth factor Receptor 2, is another receptor tyrosine kinase similar to EGFR. HER2 is involved in the regulation of cell growth, survival, and differentiation. Overexpression of the HER2 gene leads to increased cell proliferation and survival, contributing to the development of aggressive types of cancer, particularly breast cancer. HER2-positive breast cancers tend to grow faster and are more likely to spread than HER2-negative breast cancers.
