Epidermal growth factor receptor (EGFR) activating mutant variants (EGFR)

The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase that plays a critical role in regulating cell growth, survival, and differentiation (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC8199619/). Activating mutations in the EGFR tyrosine kinase domain, most commonly exon 19 deletions and the L858R point mutation, lead to constitutive, ligand-independent activation of downstream signaling pathways like PI3K/Akt and MAPK/ERK (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC2840213/). These mutations are primary drivers in a subset of non-small cell lung cancers (NSCLC), particularly in non-smokers and East Asian populations (Lung.org, https://www.lung.org/lung-health-diseases/lung-disease-lookup/lung-cancer/symptoms-diagnosis/biomarkers/egfr). Therapeutic targeting of these mutant variants with small-molecule tyrosine kinase inhibitors (TKIs) has significantly improved patient outcomes (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC8199619/). However, clinical efficacy is often limited by the emergence of acquired resistance mutations, such as T790M and C797S, necessitating the development of successive generations of inhibitors (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC10301583/). Beyond NSCLC, other variants like EGFRvIII are prevalent in glioblastoma and contribute to tumor aggressiveness and poor prognosis (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC8199619/).

Other names

ErbB-1HER1EGFRvIIIL858RExon 19 deletionT790MC797SEGFR kinase domain mutations

Tyrosine kinase inhibition via competitive binding to the ATP-binding site of the EGFR kinase domain, which prevents autophosphorylation and suppresses downstream signaling pathways such as PI3K/Akt and MAPK/ERK (NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC2840213/).