PTK2 is a potential biomarker and therapeutic target for EGFR- or TLRs-induced lung cancer progression via the regulation of the cross-talk between EGFR- and TLRs-mediated signals.

Protein tyrosine kinase 2 (PTK2), epidermal growth factor receptor (EGFR), and toll-like receptor (TLRs) are amplified in non-small cell lung cancer (NSCLC). However, the functional and clinical associations between them have not been elucidated yet in NSCLC. By using microarray data of non-small cell lung cancer (NSCLC) tumor tissues and matched normal tissues of 42 NSCLC patients, the genetic and clinical associations between PTK2, EGFR, and TLRs were analyzed in NSCLC patients. To verify the functional association, we generated PTK2-knockout (PTK2-KO) lung cancer cells by using CRISPR-Cas9 gene editing method, and performed in vitro cancer progression assay, including 3D tumor spheroid assay, and in vivo xenografted NSG (NOD/SCID/IL-2Rγ^null) mouse assay. Finally, therapeutic effects targeted to PTK2 in lung cancer in response to EGF and TLR agonists were verified by using its inhibitor (Defactinib). In summary, we identified that up-regulated PTK2 might be a reliable marker for EGFR- or TLRs-induced lung cancer progression in NSCLC patients via the regulation of the cross-talk between EGFR- and TLRs-mediated signaling. This study provides a theoretical basis for the therapeutic intervention of PTK2 targeting EGFR- or TLRs-induced lung cancer progression.