SRPIN340 (SRPIN 340) is a potent, highly selective inhibitor of serine-arginine-rich protein kinase (SRPK1) with Ki value of 0.89 uM (SRPK1). SRPIN340 does not significantly inhibit other SRPK, such as Clk1 and Clk4, as well as any additional Ser/Thr kinases. SRPIN340 is highly specific for both kinases SRPK1 and SRPK2. SRPIN340 inhibits SR phosphorylation by SRPK in Flp-In293 cells and promotes degradation of SRp75 in a dose-dependent manner. SRPIN340 (40 μM) rescues Vero cells from the cytopathic effect of Sindbis virus, with IC50 of 60 uM for Sindbis virus propagation. SRPIN340 suppressed in a dose-dependent fashion expression of a HCV subgenomic replicon and replication of the HCV-JFH1 clone in vitro. SRPIN340 also shows significant cytotoxic activity on lymphoid and myeloid leukemia cell lines, triggers early and late events of apoptosis.
