Background:

BAY 61-3606 dihydrochloride is an orally available, ATP-competitive, reversible and highly selective Syk inhibitor with a Ki of 7.5 nM an IC50 of 10 nM[1]. BAY 61-3606 dihydrochloride reduces ERK1/2 and Akt phosphorylation in neuroblastoma cell[2]. BAY 61-3606 dihydrochloride induces a large decrease of Syk phosphorylation in K-rn cell lysates[3]. Bay 61-3606 dihydrochloride sensitizes TRAIL-induced apoptosis by downregulating Mcl-1 in breast cancer cells[4].

BAY 61-3606 (0.01-10 μM ; 48 hours) significantly reduces the cell viability of SYK-positive SH-SY5Y and SYK-negative SK-N-BE cells in a dose-dependent matter. SH-SY5Y cells expressing high SYK levels are significantly more sensitive to BAY 61-3606 in comparison to SK-N-BEcells expressing very low or no SYK[2]. BAY 61-3606 (0.4 and 0.8 μM; 4 or 24 hours) inhibits SYK activity by reducing ERK1/2 and Akt phosphorylation in neuroblastoma cell SH-SY5Y[2].BAY 61-3606 (2 μM; 2 hours) induces a large decrease of Syk phosphorylation in K-rn cell lysates[3].

Bay 61-3606 (50 mg/kg; administered twice a week for two weeks by intraperitoneal injection) alone leads to more efficacious reductions than that of TNF-related apoptosis-inducing ligand (TRAIL; 10 mg/kg) alone in MCF-7 tumor xenograft-bearing BALB/c nude mice. Bay 61-3606 administered in TRAIL combination significantly reduces the volume of the xenografted tumor[4].

参考文献:
[1]. Yamamoto N, et al. The orally available spleen tyrosine kinase inhibitor 2-[7-(3,4-dimethoxyphenyl)-imidazo[1,2-c]pyrimidin-5-ylamino]nicotinamide dihydrochloride (BAY 61-3606) blocks antigen-induced airway inflammation in rodents. J Pharmacol Exp Ther. 2003 Sep;306(3):1174-81.
[2]. Tümmler C, et al. SYK Inhibition Potentiates the Effect of Chemotherapeutic Drugs on Neuroblastoma Cells in Vitro. Cancers (Basel). 2019 Feb 10;11(2). pii: E202.
[3]. Gioia R, et al. Quantitative phosphoproteomics revealed interplay between Syk and Lyn in the resistance to AMN107 in chronic myeloid leukemia cells. Blood. 2011 Aug 25;118(8):2211-21.
[4]. Kim SY, et al. Bay 61-3606 Sensitizes TRAIL-Induced Apoptosis by Downregulating Mcl-1 in Breast Cancer Cells. PLoS One. 2015 Dec 31;10(12):e0146073.