An integrin-linked machinery of cytoskeletal regulation that enables experimental tumor initiation and metastatic colonization.

ABSTRACT: Recently extravasated metastatic cancer cells use the Rif/mDia2 actin-nucleating/polymerizing machinery in order to extend integrin ?1-containing, filopodium-like protrusions (FLPs), which enable them to interact productively with the surrounding extracellular matrix; this process governs the initial proliferation of these cancer cells. Here, we identify the signaling pathway governing FLP lifetime, which involves integrin-linked kinase (ILK) and ?-parvin, two integrin:actin-bridging proteins that block cofilin-mediated actin-filament severing. Notably, the combined actions of Rif/mDia2 and ILK/?-parvin/cofilin pathways on FLPs are required not only for metastatic outgrowth but also for primary tumor formation following experimental implantation. This provides one mechanistic explanation for how the epithelial-mesenchymal transition (EMT) program imparts tumor-initiating powers to carcinoma cells, since it enhances FLP formation through the activation of ILK/?-parvin/cofilin pathway.

SUBMITTER: Shibue T 

PROVIDER: S-EPMC3864118 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature