FOXD3 Is Functionally Linked to NF-κB Signaling in KRAS G12C-Mutant NSCLC Cells.

KRAS G12C mutation is a clinically relevant driver in non-small cell lung cancer (NSCLC), yet the signaling networks that modulate malignant behavior in this context remain incompletely defined. In this study, we examined the functional role of FOXD3 and its relationship with NF-κB signaling in KRAS G12C-mutant NSCLC models. Stable FOXD3 overexpression was established in SW1573 and LU65 cells. FOXD3 reduced cell viability, migration, and invasion while increasing caspase 3/7 activity in both cell lines. Transcriptomic profiling in LU65 cells followed by Hallmark enrichment analysis identified TNFα signaling via NF-κB as a prominently altered pathway associated with FOXD3 overexpression. Consistently, NF-κB dual-luciferase assays showed reduced basal NF-κB transcriptional activity in FOXD3-overexpressing cells. TNFα stimulation partially reversed the inhibitory effects of FOXD3 on proliferation, migration, and invasion and attenuated FOXD3-induced apoptosis. In addition, stable FOXD3 overexpression suppressed xenograft growth in vivo. Collectively, these findings support a functional association between FOXD3 overexpression and reduced NF-κB-related transcriptional activity in KRAS G12C-mutant NSCLC models, although the present data do not establish direct causal mediation by NF-κB.