Wnt signaling through Snail1 and Zeb1 regulates bone metastasis in lung cancer.

Wnt-β-catenin signaling participates in the epithelial-mesenchymal transition (EMT) in a variety of cancers; however, its role in lung cancer induced bone metastasis and the underlying mechanisms remain unclear. Here, we demonstrate that β-catenin, Snail1 and Zeb1 were significantly upregulated in bone metastasis tissues from human and mouse compared with the normal controls. E-cadherin expression is negatively regulated by Zeb1, Snail1 and β-catenin during bone metastasis tissues induced by lung cancer. Knocking down Zeb1 and Snail1 in lung cancer cell lines showed increased E-cadherin mRNA expression and less invasion compared with the original cell lines. In addition, β-catenin knockdown led to the increase of E-cadherin and the decrease of Zeb1 and Snail1, which in turn inhibited the invasive properties of lung cancer. Our results demonstrated that Wnt signaling through Snail1 and Zeb1 regulates bone metastasis in lung cancer.