Epidermal growth factor receptor D770_N771insNPG (EGFR D770_N771insNPG)

Epidermal growth factor receptor (EGFR) D770_N771insNPG is a specific oncogenic variant characterized by an insertion of the amino acids Asparagine-Proline-Glycine (NPG) between residues Aspartic acid 770 and Asparagine 771 in exon 20 (MyCancerGenome, 2023). This mutation belongs to a class of EGFR exon 20 insertions that result in the constitutive activation of the kinase domain, driving uncontrolled cell proliferation and survival through the MAPK, PI3K/Akt, and STAT pathways (PubMed, PMID: 33974144). Unlike common EGFR mutations like L858R or exon 19 deletions, exon 20 insertions like D770_N771insNPG typically confer resistance to first-, second-, and third-generation tyrosine kinase inhibitors (TKIs) due to structural changes in the ATP-binding pocket (UniProt, 2024). Consequently, this variant is a critical therapeutic target in non-small cell lung cancer (NSCLC), requiring specialized treatments such as bispecific antibodies or next-generation TKIs designed to accommodate the altered binding site (FDA, 2021). Clinical management of patients with this mutation involves molecular profiling to distinguish it from more sensitive EGFR variants. Ongoing research focuses on overcoming the steric hindrance caused by the insertion to improve drug binding affinity and patient outcomes (Lancet Oncology, 2023).

Other names

EGFR exon 20 insertionERBB1 D770_N771insNPGHER1 D770_N771insNPGEpidermal growth factor receptor exon 20 insertion mutation

Small molecule inhibition of the intracellular tyrosine kinase domain or bispecific antibody binding to the extracellular domain to block ligand-induced activation and induce receptor degradation (FDA, 2021; PubMed, PMID: 34407393).