TG101209

TG101209, a small-molecule identified by structure based design, is a selective inhibitor of janus kinase 2 (Jak2) that potently inhibits Jak/Stat pathway in multiple myeloma (MM) cell lines, such as cell harboring JAK2V617F or MPLW515L/K mutations which are commonly associated with polycythemia vera (PV) and primary myelofibrosis (PMF) respectively. According to results of multiple studies, it has revealed that TG101209 exhibits a dose and time dependent cyctoxicity, which is associated with inhibited cell cycle progrgression and induced apoptosis, in a wild range of MM cell lines through suppressing the expression of pJak2, pStat3 and Bcl-xl and inducing the overexpression of pErk and pAkt.

Reference

Ramakrishnan V, Kimlinger T, Haug J, Timm M, Wellik L, Halling T, Pardanani A, Tefferi A, Rajkumar SV, Kumar S. TG101209, a novel JAK2 inhibitor, has significant in vitro activity in multiple myeloma and displays preferential cytotoxicity for CD45+ myeloma cells. Am J Hematol. 2010;85(9):675-686.

Inhibition of JAK2 signaling by TG101209 enhances radiotherapy in lung cancer models.[Pubmed:21325979]

J Thorac Oncol. 2011 Apr;6(4):699-706.

INTRODUCTION: Persistent STAT3 activation contributes to lung carcinogenesis. Survivin, one of STAT3-regulated genes, is antiapoptotic and confers cancer radioresistance. METHODS: We tested whether TG101209, a small-molecule inhibitor of JAK2 (a STAT3-activating tyrosine kinase), affected survivin expression and sensitized lung cancer to radiation. We investigated whether inhibition of JAK2 signaling with TG101209 can be used to reduce survivin expression and enhance radiosensitivity of lung cancer cells in vitro and tumor growth delay in vivo. JAK2 downstream signaling, including PI3-K/Akt and Ras/MAPK/ERK pathways, was also explored. RESULTS: TG101209 inhibited STAT3 activation and survivin expression and sensitized HCC2429 (dose enhancement ratio = 1.34, p = 0.002) and H460 (dose enhancement ratio = 1.09, p = 0.006) cells to radiation in clonogenic assays. Radiation promoted phospho-Akt and phospho-ERK in H460 cells, while their levels were unchanged in HCC2429. After treatment with TG101209, phospho-ERK protein levels were reduced in both HCC2429 and H460 cells. HCC2429 cells transfected with KRAS-12V mutant were more resistant to radiation- and TG101209-induced apoptosis than wild-type control cells. In vivo, addition of TG101209 to radiation in lung xenografts produced a significant tumor growth delay (>10 days) compared with radiation alone and was well tolerated. Immunohistochemistry staining of tumor sections showed that TG101209 increased apoptosis and decreased cell proliferation and vascular density, suggesting that TG101209 also has antiangiogenic effects. CONCLUSIONS: TG101209 enhanced the effects of radiation in lung cancer in vitro and in vivo. This study suggests the potential utility of selecting lung cancer patients according to KRAS mutation status for future clinical trials testing combination of TG101209 and radiotherapy.

TG101209, a novel JAK2 inhibitor, has significant in vitro activity in multiple myeloma and displays preferential cytotoxicity for CD45+ myeloma cells.[Pubmed:20652971]

Am J Hematol. 2010 Sep;85(9):675-86.

Interaction of myeloma cells with the bone marrow microenvironment is mediated in large part through different cytokines, especially VEGF and IL6. These cytokines, especially IL6, leads to upregulation of the JAK/STAT pathway in myeloma cell, contributing to increased proliferation, decreased apoptosis, and acquired drug resistance. Here, we examined the preclinical activity of a novel JAK2 inhibitor TG101209. TG101209 induced dose- and time-dependent cytotoxicity in a variety of multiple myeloma (MM) cell lines. The induction of cytotoxicity was associated with inhibition of cell cycle progression and induction of apoptosis in myeloma cell lines and patient-derived plasma cells. Evaluation of U266 cell lines and patient cells, which have a mix of CD45 positive and negative cells, demonstrated more profound cytotoxicity and antiproliferative activity of the drug on the CD45+ population relative to the CD45- cells. Exploring the mechanism of action of TG101209 indicated downregulation of pJak2, pStat3, and Bcl-xl levels with upregulation of pErk and pAkt levels indicating cross talk between signaling pathways. TG101209, when used in combination with the PI3K inhibitor LY294002, demonstrated synergistic cytotoxicity against myeloma cells. Our results provide the rationale for clinical evaluation of TG101209 alone or in combination with PI3K/Akt inhibitors in MM.

Cotreatment with panobinostat and JAK2 inhibitor TG101209 attenuates JAK2V617F levels and signaling and exerts synergistic cytotoxic effects against human myeloproliferative neoplastic cells.[Pubmed:19828702]

Blood. 2009 Dec 3;114(24):5024-33.

The mutant JAK2V617F tyrosine kinase (TK) is present in the majority of patients with BCR-ABL-negative myeloproliferative neoplasms (MPNs). JAK2V617F activates downstream signaling through the signal transducers and activators of transcription (STAT), RAS/mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3 (PI3)/AKT pathways, conferring proliferative and survival advantages in the MPN hematopoietic progenitor cells (HPCs). Treatment with the pan-histone deacetylase (HDAC) inhibitor panobinostat (PS) is known to inhibit the chaperone function of heat shock protein 90, as well as induce growth arrest and apoptosis of transformed HPCs. Here, we demonstrate that PS treatment depletes the autophosphorylation, expression, and downstream signaling of JAK2V617F. Treatment with PS also disrupted the chaperone association of JAK2V617F with hsp90, promoting proteasomal degradation of JAK2V617F. PS also induced apoptosis of the cultured JAK2V617F-expressing human erythroleukemia HEL92.1.7 and Ba/F3-JAK2V617F cells. Treatment with the JAK2 TK inhibitor TG101209 attenuated JAK2V617F autophosphorylation and induced apoptosis of HEL92.1.7 and Ba/F3-JAK2V617F cells. Cotreatment with PS and TG101209 further depleted JAK/STAT signaling and synergistically induced apoptosis of HEL92.1.7 and Ba/F3-JAK2V617F cells. Cotreatment with TG101209 and PS exerted greater cytotoxicity against primary CD34(+) MPN cells than normal CD34(+) HPCs. These in vitro findings suggest combination therapy with HDAC and JAK2V617F inhibitors is of potential value for the treatment of JAK2V617F-positive MPN.

TG101209 is a selective JAK2 inhibitor with IC50 of 6 nM, less potent to Flt3 and RET with IC50 of 25 nM and 17 nM, appr 30-fold selective for JAK2 than JAK3, and sensitive to JAK2V617F and MPLW515L/K mutations.

TG101209,936091-14-4,Natural Products,c-RET, buy TG101209 , TG101209 supplier , purchase TG101209 , TG101209 cost , TG101209 manufacturer , order TG101209 , high purity TG101209