214 Background: Even with successful surgical resection and treatment pancreatic adenocarcinoma has a high incidence of recurrence because of metastatic spread. Vascular endothelial growth factor receptor 3 (VEGFR3) is related to lymphatic metastasis. VEGFR3 binds to the survival protein, focal adhesion kinase (FAK), to promote pancreatic cancer (PC) lymphangiogenesis. In this study we have pinpointed the site of interaction of VEGFR3 and FAK to create drug capable of disrupting their signaling with antitumor effect. Methods: 200,000 small molecules were screened in silico for their abilities to interact with the VEGFR3 /FAK binding site. Effects of the selected compounds on PC cell lines MiaPaCa2 and Panc1 were examined by MTT assay (viability), BrdU incorporation (proliferation), Boyden chamber (motility), TUNEL and flow cytometry (cell cycle, apoptosis), and Western blot (phosphorylation, apoptosis). Results: We selected compound C4 because it disrupted the FAK-VEGFR3 complexes in PC cells, as was shown by immunoprecipitation. It caused a dose-dependent dephosphorylation and inactivation of the VEGFR3. Inhibition of VEGFR3 with 10μM of C4 resulted in 80% reduction in cell viability, decrease in proliferation and a 50% reduction in motility. Treatment led to apoptosis in PC cells, confirmed by PARP cleavage. C4 increased the sensitivity of PC cells to chemotherapy in vitro. MiaPaca2 have shown 40% apoptosis after only 24 h of treatment with combination of C4 and gemcitabine at nanomolar concentrations ineffective alone. C4 reduced tumor growth in vivo in murine models of PC. C4 (60 mg/kg, daily IP) decreased tumor growth after 21 days of treatment to 60% (P=0.017). Lower dose of the C4 (10 mg/kg) still had an effect and inhibited tumor growth by 30%, but concomitant administration with low dose of gemcitabine (4 mg/kg, Q4dx6), had significant synergistic effect and led to 80% of tumor reduction. We also have shown that combination of C4 with gemcitabine had prolonged cytostatic effect on tumor growth after treatment withdrawal. Conclusions: Targeting the scaffolding function of FAK with the small-molecule inhibitors can be effectively used to develop potential oral-based PC therapeutics. [Table: see text]