WISP-3 promotes tumor-monocyte adhesion through a MEK/ERK-dependent miR-12131/ICAM-4 axis in lung adenocarcinoma.

Tumor-immune cell interactions critically contribute to the progression of non-small cell lung cancer (NSCLC). In this study, we investigated the role of WNT1-inducible signaling pathway protein 3 (WISP-3) in regulating tumor cell adhesion and the underlying molecular mechanisms in lung adenocarcinoma cells. Treatment with recombinant WISP-3 significantly increased intercellular adhesion molecule-4 (ICAM-4) expression at both mRNA and protein levels in A549 and H1299 cells in a dose-dependent manner. Consistently, WISP-3 enhanced tumor-monocyte adhesion, indicating its involvement in tumor-immune cell interactions. Mechanistically, WISP-3 stimulated rapid activation of the MEK/ERK signaling cascade, as demonstrated by increased phosphorylation of MEK and ERK. Pharmacological inhibition of MEK using PD98059 or U0126, as well as direct inhibition of ERK with SCH772984, markedly attenuated WISP-3-induced ICAM-4 expression and THP-1 adhesion. These findings were further supported by siRNA-mediated knockdown of MEK or ERK, confirming the essential role of this pathway. In addition, WISP-3 suppressed the expression of hsa-miR-12131, which was identified as a negative regulator of ICAM-4. Restoration of hsa-miR-12131 significantly reduced ICAM-4 expression and impaired tumor-monocyte adhesion, indicating that miR-12131 functions downstream of MEK/ERK signaling. Collectively, these results demonstrate that WISP-3 promotes ICAM-4-dependent monocyte adhesion through activation of the MEK/ERK pathway and subsequent suppression of hsa-miR-12131. This WISP-3/MEK/ERK/miR-12131/ICAM-4 axis provides new insight into tumor-immune interactions in NSCLC and highlights potential therapeutic targets.