Mubritinib (TAK 165)S2216

Mubritinib displays > 4000-fold selectivity over other tyrosine kinases, such as EGFR, FGFR, PDGFR, Jak1, Src and Blk. Mubritinib even at low concentration of 0.1 μM significantly blocks HER2 phosphorylation, leading to the downregulation of PI3K-Akt and MAPK pathway in cell line BT474 with high level of HER2. Mubritinib not only exhibits highly potent antiproliferative effect in ErbB2-overexpressing cancer cell line BT474 with an IC50 of 5 nM, but also displays marked antiproliferative effects in cell lines with HER2 expressed weakly with IC50 of 53 nM, 90 nM and 91 nM for LNCaP, LN-REC4 and T24, respectively. Mubritinib displays no inhibitory activities against PC-3 cells with HER2 expressed very faintly with IC50 of 4.62 μM, as well as EGFR-overexpressing HT1376 and ACHN cell lines with IC50 of >25 μM. ^[1]