GSK 2830371 is an orally active, allosteric Wip1 phosphatase inhibitor with IC50 of 6 nM.

Wip1 phosphatase:6 nM

In the PPM1D-amplified MCF7 breast carcinoma cells, GSK2830371 increases the phosphorylation of multiple Wip1 substrates, including p53 (S15), Chk2 (T68), H2AX (S139) and ATM (S1981). GSK2830371 shows selective antiproliferative activity in a subset of lymphoid cell lines, all of which carry a wild-type TP53 allele. Furthermore, co-treatment of doxorubicin and GSK2830371 results in a synergistic antiproliferative effect in DOHH2 and MX-1 tumor cells. [1]

In vivo, GSK2830371 increases phosphorylation of Chk2 (T68) and p53 (S15) and decreases Wip1 protein concentrations in DOHH2 tumors. GSK2830371 (150 mg/kg p.o.) also inhibits the growth of DOHH2 tumor xenografts via inhibition of Wip1. [1]

In vitro phosphatase assays: The primary in vitro Wip1 enzymatic assay measures fluorescence generated by Wip-1 (2–420) hydrolysis of fluorescein diphosphate (FDP). 50 μM FDP substrate with compound or DMSO is added at room temperature before addition of 10 nM Wip1 in assay buffer (50 mM TRIS, pH 7.5, 30 mM MgCl2, 0.8 mM CHAPS, 0.05 mg/ml BSA). Fluorescent signal is detected on a Spectramax microplate reader (485/530 nm).

Cells are seeded into 96 well plates at 200–400 cells per well and treated with a compound dilution series on day 1. After 7 d, The CellTiter-Glo cell viability assay is used to determine effects on cell growth. Luminescent signal is detected on an EnVision 2104.(Only for Reference)