Cellular Origins of EGFR-Driven Lung Cancer Cells Determine Sensitivity to Therapy

Targeting the epidermal growth factor receptor (EGFR) with tyrosine kinase inhibitors (TKIs) is one of the major precision medicine treatment options for lung adenocarcinoma. Due to common development of drug resistance to first- and second-generation TKIs, third-generation inhibitors, including osimertinib and rociletinib, have been developed. A model of EGFR-driven lung cancer and a method to develop tumors of distinct epigenetic states through 3D organotypic cultures are described here. It is discovered that activation of the EGFR T790M/L858R mutation in lung epithelial cells can drive lung cancers with alveolar or bronchiolar features, which can originate from alveolar type 2 (AT2) cells or bronchioalveolar stem cells, but not basal cells or club cells of the trachea. It is also demonstrated that these clones are able to retain their epigenetic differences through passaging orthotopically in mice and crucially that they have distinct drug vulnerabilities. This work serves as a blueprint for exploring how epigenetics can be used to stratify patients for precision medicine decisions

Polycomb deficiency drives a FOXP2-high aggressive state targetable by epigenetic inhibitors

Delineating the specific role of Polycomb Repressive Complex 2 (PRC2) in various cancer systems is desirable as inhibitors for EZH2 inhibitors are approved for some cancers. Here the authors show haplo- and full-insufficiency of EZH2 drive divergent phenotypes in lung cancer. 3D tumoroids recapitulate transcriptional profiles, including FOXP2 derepression, and drug responses of in vivo tumors