HER-2 and EGFR (epidermal growth factor receptor) are both types of cell surface receptors that are involved in regulating cell growth, division, and survival.

HER-2 (also known as ErbB2) is a member of the HER family of receptors, which also includes HER-1 (EGFR), HER-3, and HER-4. HER-2 is overexpressed in some types of cancer, including breast cancer, and plays a critical role in tumor growth and progression. HER-2 targeted therapies, such as trastuzumab (Herceptin), have been developed to treat HER-2 positive breast cancer by specifically blocking HER-2 signaling.

EGFR is a receptor that binds to epidermal growth factor (EGF) and other ligands, leading to the activation of downstream signaling pathways that promote cell growth and survival. EGFR is frequently overexpressed in a variety of cancers, including lung, colon, and head and neck cancers. EGFR inhibitors, such as erlotinib (Tarceva) and gefitinib (Iressa), have been developed to target EGFR signaling and are used in the treatment of certain types of cancer.

Both HER-2 and EGFR play important roles in cancer development and are therapeutic targets for certain types of cancer. However, the expression and activity of these receptors can vary widely between different types of cancer and even between individual tumors, highlighting the need for personalized treatment approaches.