The mechanism of contribution of integrin linked kinase (ILK) to epithelial-mesenchymal transition (EMT)

Integrin linked kinase (ILK) is ubiquitously expressed serine/threonine protein kinase, a binding partner of β1 and β3 integrin subunit as a cytoplasmic effector of integrin receptors that functionally links them to the actin cytoskeleton.We postulate that ILK is important enzyme involved in epithelial-mesenchymal transition (EMT) a critical event in the process of cancer progression. Commonly used EMT molecular markers include among others increased expression of N-cadherin and vimentin, nuclear localization of β-catenin, and the decrease of E-cadherin synthesis. In this study we were able to show that N-cadherin expression in melanoma cells is dependent on ILK signaling and the translocation of β-catenin to the nucleus. Silencing of ILK expression by siRNA significantly inhibited the stabilization and subsequent nuclear translocation of β-catenin and the expression of N-cadherin, a crucial molecule in the EMT, which facilitates association with fibroblast and endothelial cells during invasion of various cancers. The results allow to cautiously speculate on the important role of ILK in the cross-talk between integrins and cadherins accompanying EMT in melanoma.