Abstract 1653: Vasodilator-stimulated phosphoprotein ser157 and ser239 are antimetastatic targets in colon cancer

Abstract Colorectal cancer is the third deadly cancer worldwide. Patient mortality is largely the result of metastatic disease progression, in which tumor cells undergo dramatic morphological changes characterized by the formation of membrane protrusive structures mediating invasion (lamellipodia, filopodia, invadopodia). These events are driven by the activity of actin-regulatory proteins, including the vasodilator-stimulated phosphoprotein (VASP), which reorganize the actin cytoskeleton to promote cell migration and invasion. In colon cancer, cAMP- and cGMP-dependent VASP phosphorylation at Ser157 (pVASP-Ser157) and Ser239 (pVASP-Ser239) represent opposing molecular switches, which regulate the invasive cell shape. Here, pVASP-Ser157 and pVASP-Ser239 differentially affected the metastatic potential of colon cancer cells, including tumor proliferation, colony formation, migration, adhesion and metastasis in vivo. Investigations employed intestinal cancer cells, human tumor cells expressing serine phosphoresistant VASP mutants, cGMP or cAMP analogs, agonists selectively elevating intracellular cGMP or cAMP levels, and orthotopic mouse models of colorectal cancer. Collectively, results demonstrated pVASP-Ser239 suppresses, while pVASP-Ser157 promoted, the metastatic phenotype of colon cancer cells. Thus, differential VASP serine phosphorylation is a novel targeted strategy to prevent colon cancer metastasis. Clinical translation of these findings may provide original therapeutic interventions to reduce mortality in patients with colon cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1653. doi:10.1158/1538-7445.AM2011-1653