Inhibition of the focal adhesion kinase and vascular endothelial growth factor receptor‐3 interaction leads to decreased survival in human neuroblastoma cell lines

Abstract

Neuroblastoma continues to be a devastating childhood solid tumor and is responsible for over 15% of all childhood cancer related deaths. Focal adhesion kinase (FAK) and vascular endothelial growth factor receptor-3 (VEGFR-3) are protein tyrosine kinases that are overexpressed in a number of human cancers, including neuroblastoma. These two kinases can directly interact and provide survival signals to cancer cells. In this study, we utilized siRNA to VEGFR-3 to demonstrate the biologic importance of this kinase in neuroblastoma cell survival. We also used confocal microscopy and immunoprecipitation to show that FAK and VEGFR-3 bind in neuroblastoma. Finally, employing a 12-amino-acid peptide (AV3) specific to VEGFR-3, we showed that the colocalization between FAK and VEGFR-3 could be disrupted, and that disruption resulted in decreased neuroblastoma cell survival. These studies provide insight to the FAK - VEGFR-3 interaction in neuroblastoma and demonstrate its importance in this tumor type. Focusing upon the FAK - VEGFR-3 interaction may provide a novel therapeutic target for the development of new strategies for treatment of neuroblastoma.

Inhibition of FAK and VEGFR‐3 binding decreases tumorigenicity in neuroblastoma

“…In the current study, we have demonstrated that small molecule interruption of the FAK-VEGFR-3 interaction in neuroblastoma cells resulted in decreased cellular survival. We have also seen similar in vitro findings using a peptide to inhibit the FAK-VEGFR-3 interaction [29]. The interaction of FAK with other proteins and growth factor receptors is not unique, or limited to, VEGFR-3.…”

“…There have been recent reports describing the interaction between FAK and VEGFR‐3, and showing that disruption of this interaction with homologous peptides or small molecules resulted in decreased tumor cell survival []. We have demonstrated that FAK and VEGFR‐3 interact in human neuroblastoma cell lines [], and now hypothesize that inhibition of this interaction would result in decreased neuroblastoma tumorigenicity. The data from the current study showed that disruption of the FAK–VEGFR‐3 interaction with chloropyramine hydrochloride (C4) resulted in decreased neuroblastoma attachment, invasion and survival.…”

“…Western blots were performed as previously described []. Briefly, cells were treated with the agent under study, then lysed on ice for 30 min in a buffer containing 50 mM Tris–HCL, (pH 7.5), 150 mM NaCl, 1% Triton‐X, 0.5% sodium deoxycholate (NaDOC), 0.1% SDS, 5 mM EDTA, 50 mM NaF, 1 mM NaVO 3 , 10% glycerol, and protease inhibitors: 10 µg/mL leupeptin, 10 µg/mL PMSF and 1 µg/mL aprotinin.…”

Regulation of expression level of fms-like tyrosine kinase-4 is related to osteoclast differentiation

“…Many cellular factors were involved in the regulation of osteoclast differentiation and their functions [ 3 – 5 , 22 – 24 ]. It have been reported that mutations of Flt-4 lead to Milroy disease, which is an autosomal dominant condition associated with congenital lymphedema [ 16 , 17 ]. In this study, we found that VEGF-C increased production of osteoclasts of mouse bone marrow cells and RAW264.7 cells.…”

“…Flt-4 is important for many signaling pathways. Interaction of Flt-4 and the focal adhesion kinase is related to survival of human neuroblastoma cell lines [ 16 ]. Mutations in Flt-4 result in Milroy disease, which is an autosomal dominant condition associated with congenital lymphedema [ 17 ].…”