LY2109761 is a novel selective TGF-β receptor type I/II (TβRI/II) dual inhibitor with Ki of 38 nM and 300 nM in a cell-free assay, respectively; shown to negatively affect the phosphorylation of Smad2.
LY2109761 treatment induces a dose-dependent low-anchorage growth inhibition of L3.6pl/GLT cells, leading to ~33% or 73% inhibition at 2 μM and 20 μM, respectively, which can be strongly enhanced when combined with gemcitabine in combination index value of 0.36581. Blocking TβRI/II kinase activity with LY2109761 (5 μM) completely suppresses both the basal and TGF-β1-stimulated migration and invasion of L3.6pl/GLT cells, significantly enhances the detachment-induced apoptosis by 26% at 8 hours treatment, and completely suppresses TGF-β–induced Smad2 phosphorylation. LY2109761 treatment at 1 nM is sufficient to significantly block the migration and invasion but not adhesion of hepatocellular carcinoma cells by increasing E-cadherin expression. LY2109761 pretreatment enhances radiosensitivity of glioblastoma cells via TGF-β signaling blockage. LY2109761 (10 μM) reduces the self-renewal and proliferation of GBM-derived cancer stem–like cells (CSLC), which can be significantly enhanced when combined with radiation.
Administration of LY2109761 (50 mg/kg) alone or in combination with gemcitabine (25 mg/kg) significantly reduces the tumor volume by ~70% and ~90%, respectively, prolongs the survival with the median survival duration of 45.0 days and 77.5 days, respectively, and reduces spontaneous abdominal metastases in the L3.6pl/GLT Xenograft mice model. In consistent with the in vitro effect, administration of LY2109761 alone or in combination with radiation, markedly inhibits tumor growth in the orthotopical CSLC glioblastoma model by 43.4% and 76.3%, respectively, decreases tumor invasion and tumor microvessel density, and significantly enhances radiation-induced tumor growth delay in the U87MG xenograft mice model.
LY2157299 is a small molecule inhibitor of the TGF-β receptor type 1/type II kinases (IC50 = 69 nM). It has been used to study the role of TGF-β signaling in tumor cell migration and metastasis in pancreatic tumor cell lines where 5 μM of the compound completely disrupts Smad-2 phosphorylation, an immediate downstream target of the kinase activity. It can also suppress radiation-induced inflammatory cytokine signaling and proangiogenic genes, including ID1, in human primary fibrobalsts.
LY 2109761 is a novel transforming growth factor beta receptor type I and type II dual inhibitor that is potentially used to treat and suppress pancreatic cancer.
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