[Description]:
WP1066 is an inhibitor of JAK2 and STAT3, and also shows effect on STAT5 and ERK1/2, without affecting JAK1 and JAK3.
[Related Catalog]:
[Target]
[In Vitro]
WP1066 markedly inhibits the growth of HEL cells in a dose-dependent manner. The IC50 value for inhibition of the proliferation of HEL cells is 2.3 μM. WP1066 inhibits the growth of human HEL cells carrying the JAK2 V617F mutant isoform[1]. Blockade of p-STAT3 with WP1066 enhances the cytotoxic effects of CTX on the tumor. The IC50 doses of WP1066 for B16 cells is 2.43 µM (0.865 µg/mL)[2]. WP1066 inhibits AML blast colony-forming cell proliferation, suppresses normal BM progenitor proliferation at increased concentrations, and inhibits AML colony-forming cell proliferation[3].
[In Vivo]
WP1066 (30 mg/kg, o.g.)does not further enhance the therapeutic effects of cyclophosphamide on pulmonary melanoma lesions, enhance the therapeutic effects of cyclophosphamide against CNS melanoma, or further enhance immune-mediated cytotoxic effects of CTX in C57BL/6J mice. WP1066 exerts an additive effect to CTX inhibition of the p-STAT3 pathway within the tumor microenvironment[2].
[Cell Assay]
Briefly, fresh low-density peripheral blood cells and various cell lines at the logarithmic phase of their growth are washed twice in RPMI 1640 containing 10% FCS and counted in a hemocytometer. Cell viability is assessed by the trypan blue (0.1%) staining method. Equal numbers of viable cells (5×104 per well) are incubated in a total volume of 100 μL of RPMI 1640 supplemented with 10% FCS alone or with WP1066 at increasing concentrations; the incubations are continued for up to 72 h in 96-well flat-bottomed plates at 37°C in a humidified 5% CO2 atmosphere. Experiments for each condition are done in triplicate. After incubation, 20 μL of CellTiter96 One Solution Reagent are added to each well. The plates are then incubated for an additional 60 min at 37°C in a humidified 5% CO2 atmosphere. Immediately after incubation, absorbance is read using a 96-well plate reader at a wavelength of 490 nm.
[Animal admin]
To ascertain the inhibition of the immune populations within the spleen and peripheral blood compartments, tumor-bearing mice are treated with CTX, WP1066, or CTX in combination with WP1066, for 14 days. Single-cell suspensions are prepared from spleens and the peripheral blood of mice and single cells are surface-stained with FITC-conjugated anti-CD4 (L3T4) or PE-conjugated anti-CD8 (53-6.7) and are intracellularly stained with APC-conjugated-FoxP3 (clone FJK-16s). The cell number of CD4+ and CD8+ T cells in the peripheral blood is counted based on positive surface staining of the respective markers relative to the total cell count of PBMCs. The percentage of FoxP3+ Tregs is calculated within the peripheral blood and within the CD4 compartment.
[References]
[1]. Verstovsek S, et al. WP1066, a novel JAK2 inhibitor, suppresses proliferation and induces apoptosis in erythroid human cells carrying the JAK2 V617F mutation. Clin Cancer Res, 2008, (3), 788-796.
[2]. Hatiboglu MA, et al. The tumor microenvironment expression of p-STAT3 influences the efficacy of cyclophosphamide with WP1066 in murine melanoma models. Int J Cancer, 2012, 131(1), 8-17
[3]. Ferrajoli A, et al. WP1066 disrupts Janus kinase-2 and induces caspase-dependent apoptosis in acute myelogenous leukemia cells. Cancer Res, 2007, 67(23), 11291-11299.
[Related Small Molecules]