Vasodilator-stimulated phosphoprotein promotes liver metastasis of gastrointestinal cancer by activating a β1-integrin-FAK-YAP1/TAZ signaling pathway

Abstract

Extracellular matrix (ECM)-induced β1-integrin-FAK signaling promotes cell attachment, survival, and migration of cancer cells in a distant organ so as to enable cancer metastasis. However, mechanisms governing activation of the β1-integrin-FAK signaling remain incompletely understood. Here, we report that vasodilator-stimulated phosphoprotein (VASP), an actin binding protein, is required for ECM–mediated β1-integrin-FAK-YAP1/TAZ signaling in gastrointestinal (GI) cancer cells and their liver metastasis. In patient-derived samples, VASP is upregulated in 53 of 63 colorectal cancers and 43 of 53 pancreatic ductal adenocarcinomas and high VASP levels correlate with liver metastasis and reduced patient survival. In a Matrigel-based 3-dimensional (3D) culture model, short hairpin RNA (shRNA)–mediated VASP knockdown in colorectal cancer cells (KM12L4, HCT116, and HT29) and pancreatic cancer cells (L3.6 and MIA PaCa-1) suppresses the growth of 3D cancer spheroids. Mechanistic studies reveal that VASP knockdown suppresses FAK phosphorylation and YAP1/TAZ protein levels, but not Akt or Erk-related pathways and that YAP1/TAZ proteins are enhanced by the β1-integrin-FAK signaling. Additionally, VASP regulates the β1-integrin-FAK-YAP1/TAZ signaling by at least two mechanisms: (1) promoting ECM-mediated β1-integrin activation and (2) regulating YAP1/TAZ dephosphorylation at downstream of RhoA to enhance the stability of YAP1/TAZ proteins. In agreement with these, preclinical studies with two experimental liver metastasis mouse models demonstrate that VASP knockdown suppresses GI cancer liver metastasis, β1-integrin activation, and YAP1/TAZ levels of metastatic cancer cells. Together, our data support VASP as a treatment target for liver metastasis of colorectal and pancreatic cancers.

p300 Acetyltransferase Is a Cytoplasm‐to‐Nucleus Shuttle for SMAD2/3 and TAZ Nuclear Transport in Transforming Growth Factor β–Stimulated Hepatic Stellate Cells

“…HT29 human colorectal cancer cells and Lewis lung carcinoma cells (LLCs) were purchased from ATCC. L3.6 human pancreatic cancer cells were provided by Dr. Raul Urrutia (Medical College of Wisconsin) (20) and LX2 cells were from Dr. Scott Friedman (Icahn School of Medicine at Mount Sinai). Cells were authenticated by Genetica.…”

“…Subcutaneous HSC/tumor injection into nude mice and in vivo xenogen imaging were done as described (23, 25). LLCs were implanted into p300 F/F cre mice by intrasplenic injection (20) and L3.6 cells were injected into SCID mice by portal vein injection (23, 24). Details about control and p300 F/F cre mice, and tumor injection protocols are in Supplementary Materials and Methods.…”

Cytoskeletal Remodeling in Cancer

“…In colon cancer cells phosphorylation of VASP at Ser 239 suppressed the formation of filopodia and invadopodia inhibiting the migration of cancer cells [236]. In patients with gastrointestinal cancer VASP is required for the ECM-mediated β1-integrin-FAK-YAP1/TAZ signaling, and high levels of protein expression in colorectal cancers pancreatic ductal adenocarcinomas significantly correlated with liver metastasis and reduced patient survival [237]. Wang et al showed that miRNA-610 inhibits the invasion of gastric cancer cells by suppressing the expression of VASP, which could be used therapeutically to inhibit gastric cancer progression and metastasis [238].…”

Association between Inflammation and Function of Cell Adhesion Molecules Influence on Gastrointestinal Cancer Development

“…Integrins overexpressed in gastrointestinal cancer are known to regulate tumor progression. For instance, ECM-mediated integrin β1 promotes liver metastasis of gastrointestinal cancer through focal adhesion kinase (FAK)-yes-associated protein 1 (YAP1)/tafazzin (TAZ) signaling, which is enhanced by vasodilator-stimulated phosphoprotein (VASP) [116]. In addition, ECM1-mediated integrin β4 promotes EMT and glucose metabolism via SOX2/HIF-1α signaling in gastric cancer [117] and modulates epidermal growth factor receptor (EGFR) signaling to induce gefitinib chemoresistance [118].…”