Abstract
Angiogenesis is a pivotal process for tumor progression and metastasis in non-small cell lung cancer (NSCLC). However, the molecular mechanisms by which WNT1-inducible signaling pathway protein 3 (WISP-3) contributes to NSCLC angiogenesis remain poorly defined. This study investigated the role of WISP-3 in regulating pro-angiogenic signaling in lung adenocarcinoma (LUAD) cells. Conditioned medium from H1299 and A549 cells treated with recombinant WISP-3 (0-100 ng/mL) significantly and dose-dependently enhanced the tube formation of human umbilical vein endothelial cells (HUVECs). WISP-3 selectively upregulated platelet-derived growth factor A (PDGF-A) expression at both mRNA and protein levels in NSCLC cell lines, while other angiogenic factors remained unaffected. Notably, knockdown of PDGF-A using siRNA markedly abolished WISP-3-induced HUVEC tube formation, confirming PDGF-A as a critical mediator in this process. Mechanistically, WISP-3 rapidly triggered the phosphorylation of p38 and JNK signaling pathways. These activations led to the phosphorylation of the transcription factor c-Jun, which in turn promoted PDGF-A gene expression. Pharmacological inhibition of p38 (Adezmapimod), JNK (SP600125), or c-Jun (T-5224) effectively suppressed WISP-3-induced c-Jun activation, PDGF-A expression, and subsequent angiogenesis. Collectively, our findings identify a novel WISP-3/p38-JNK/c-Jun/PDGF-A signaling axis that drives vascular remodeling in NSCLC. Targeting WISP-3 or its downstream effectors may represent a promising therapeutic strategy for anti-angiogenic treatment in lung cancer.