Start Your Search
MINI 21 - Novel Targets (ID 133)
- Event: WCLC 2015
- Type: Mini Oral
- Track: Biology, Pathology, and Molecular Testing
- Presentations: 1
MINI21.11 - A Novel Cell Line Model of EGFR Exon 20 Insertion Mutations (ID 2828)
16:45 - 18:15 | Author(s): A. Estrada-Bernal
In-frame insertions in exon 20 of EGFR are infrequent activating mutations in the tyrosine kinase domain that have decreased sensitivity to EGFR inhibitors and currently have no available targeted therapies. In vitro studies ectopically expressing some of the common insertions (3 to 21 bp between codons 762 and 770) show reduced sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Non-small cell lung cancer (NSCLC) patients whose tumors harbor these mutations do not respond to EGFR kinase inhibitors. To date, there are no known patient-derived cell lines that harbor the EGFR exon 20 insertions that recapitulate patient insensitivity to EGFR TKIs. Here we report the isolation and characterization of a patient derived cell line with an EGFR exon20 insertion.
The CUTO-14 cell line was derived from a malignant pleural effusion of a lung adenocarcinoma patient harboring the EGFR exon 20 insertion p.A767_V767dupASV after obtaining IRB-approved informed consent. PCR amplification of EGFR exon 20 and subsequent Sanger sequencing was performed on genomic DNA isolated from CUTO-14. H3255 (L858R) and HCC827 (exon 19 del) cell lines were used as controls because they harbor sensitizing EGFR mutations. Cell viability was evaluated by MTS proliferation assay. Phosphorylation status and signaling was analyzed by western blot and an EGFR phosphorylation array. For tumor xenograft studies, nude mice were injected with 1.5 x 10 cells in matrigel and evaluated weekly for tumor growth.
Genomic sequencing of CUTO-14 demonstrated that the cell line maintains the pA767_V767dupASV EGFR exon 20 insertion. CUTO-14 showed relative resistance to gefitinib inhibition compared to HCC827 and H3255 in ERK1/2 phosphorylation assays. CUTO-14 also demonstrated reduced sensitivity to gefitinib compared to HCC827 and H3255 in cell proliferation assays. Tumor formation was observed in mice after injection in nude mice.
CUTO-14 cells represent a novel model for the investigation of therapeutic strategies for EGRF exon 20 insertions mutations. The cell line has the ability to develop tumors in vivo and importantly shows reduced sensitivity to EGFR TKIs mimicking the lack of response in patients with these mutations.
Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.