Aim: To investigate the molecular targets of DCLAK11, a novel compound discovered from a series of substituted pyridin-3-amine derivatives, and to characterize its anti-tumor properties in vitro.
Methods: Kinase inhibition was measured by an ELISA assay. Cell viability was assessed with an SRB or a CCK8 assay. The alterations induced by kinase signaling proteins in cancer cells were detected by Western blot. Apoptosis was determined by an Annexin V-PI assay. The following assays were used to evaluate the impact on angiogenesis: wound-healing, Transwell, tube formation and microvessel outgrowth from rat aortic rings.
Results: DCLAK11 was a multi-targeted kinase inhibitor that primarily inhibited the EGFR, HER2, and VEGFR2 tyrosine kinases with IC50 value of 6.5, 18, and 31 nmol/L, respectively. DCLAK11 potently inhibited the proliferation of EGFR- and HER2-driven cancer cells: its IC50 value was 12 and 22 nmol/L, respectively, in HCC827 and HCC4006 cells with EGFR exon deletions, and 19 and 81 nmol/L, respectively, in NCI-N87 and BT474 cells with HER2 amplification. Consistently, DCLAK11 blocked the EGFR and HER2 signaling in cancer cells with either an EGFR or a HER2 aberration. Furthermore, DCLAK11 effectively induced EGFR/HER2-driven cell apoptosis. Moreover, DCLAK11 exhibited anti-angiogenic activity, as shown by its inhibitory effect on the proliferation, migration and tube formation of human umbilical vascular endothelial cells and the microvessel outgrowth of rat aortic rings.
Conclusions: DCLAK11 is a multi-targeted kinase inhibitor with remarkable potency against tyrosine kinases EGFR, HER2 and VEGFR2, which confirms its potent anti-cancer activity in EGFR- and HER2-addicted cancers and its anti-angiogenic activity.