TG101209

Cell experiment:

In brief, approximately 2×103 cells are plated into microtiterplate wells in 100 mL RPMI-1640 growth media with indicated concentrations of TG101209. The relative growth of cells is quantified at 24-hour intervals using Cell Proliferation Kit II (XTT) as per manufacturer's guidelines. After incubation, 20 mL of XTT is added to the wells and allowed to incubate for 4-6 hours. The colored formazan product is measured spectrophotometrically at 450 nm with correction at 650 nm, and IC50 values are determined using the GraphPad Prism 4.0 software. Data are subjected to a non-linear regression-fit analysis and IC50 values are determined as the concentration that inhibits proliferation by 50%. All experiments are done in triplicate and the results normalized to growth of untreated cells.

Animal experiment:

Severe combined immunodeficiency (SCID) mice are intravenously injected with 10 times 106 sorted GFP-positive BaF/3 cells expressing JAK2V617F (Ba/F3-V617F-GFP). TG101209 is administered by oral gavage at the indicated doses beginning day +3 after tumor cell infusion and ending on day +20. On day +11 following tumor cell injection, 1 mL blood is collected by terminal cardiac bleeding from the mouse that receives vehicle, and 0.1 mL of blood is collected by non-lethal retro-orbital collection from each of the three six-mouse groups dosed with 10, 30 or 100 mg/kg b.i.d. (twice daily) of TG101209, and samples pooled within the dose groups. Blood mononuclear cells are isolated by a Ficoll cushion centrifugation method (600 RCF and 30 min). The isolated cells are subjected to FACS analysis to determine the percentage of GFP-positive tumor cells (that is, Ba/F3-V617F-GFP cells).

References:

[1]. Pardanani A, et al. TG101209, a small molecule JAK2-selective kinase inhibitor potently inhibits myeloproliferative disorder-associated JAK2V617F and MPLW515L/K mutations. Leukemia. 2007 Aug;21(8):1658-68.
[2]. Ma AC, et al. A novel zebrafish jak2a(V581F) model shared features of human JAK2(V617F) polycythemia vera. Exp Hematol. 2009 Dec;37(12):1379-1386.e4.
[3]. Sun Y, et al. Inhibition of JAK2 signaling by TG101209 enhances radiotherapy in lung cancer models. J Thorac Oncol. 2011 Apr;6(4):699-706
[4]. Cuesta-Dominguez A, et al. Transforming and tumorigenic activity of JAK2 by fusion to BCR: molecular mechanisms of action of a novel BCR-JAK2 tyrosine-kinase. PLoS One. 2012;7(2):e3245