HER2 is part of the ErbB family of receptors. These receptors are tyrosine kinases that play a crucial role in the regulation of cell growth and survival. When HER2 is overexpressed, it leads to the persistent activation of these signaling pathways, causing excessive cell proliferation and survival, which eventually contributes to tumorigenesis. HER2-positive cancers are often more aggressive and have a higher likelihood of recurrence compared to HER2-negative cancers.
