| Reference | 1. Mol Cancer Ther. 2014 May;13(5):1246-58. doi: 10.1158/1535-7163.MCT-13-0605. Epub 2014 Feb 27.<br />
Pharmacologic suppression of JAK1/2 by JAK1/2 inhibitor AZD1480 potently inhibits IL-6-induced experimental prostate cancer metastases formation.<br />
Gu L(1), Talati P, Vogiatzi P, Romero-Weaver AL, Abdulghani J, Liao Z, Leiby B, Hoang DT, Mirtti T, Alanen K, Zinda M, Huszar D, Nevalainen MT.<br />
Author information:<br />
(1)Authors' Affiliations: Departments of Cancer Biology, Urology, and Medical Oncology, Kimmel Cancer Center; Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania; Oncology iMED, AstraZeneca R&D Boston, Waltham, Massachusetts; Department of Pathology, Haartman Institute; Institute of Molecular Medicine, University of Helsinki, Helsinki; and Department of Pathology, Institute of Biomedicine, University of Turku, Turku, Finland.<br />
Metastatic prostate cancer is lethal and lacks effective strategies for prevention or treatment, requiring novel therapeutic approaches. Interleukin-6 (IL-6) is a cytokine that has been linked with prostate cancer pathogenesis by multiple studies. However, the direct functional roles of IL-6 in prostate cancer growth and progression have been unclear. In the present study, we show that IL-6 is produced in distant metastases of clinical prostate cancers. IL-6-activated signaling pathways in prostate cancer cells induced a robust 7-fold increase in metastases formation in nude mice. We further show that IL-6 promoted migratory prostate cancer cell phenotype, including increased prostate cancer cell migration, microtubule reorganization, and heterotypic adhesion of prostate cancer cells to endothelial cells. IL-6-driven metastasis was predominantly mediated by Stat3 and to lesser extent by ERK1/2. Most importantly, pharmacologic inhibition of Jak1/2 by AZD1480 suppressed IL-6-induced signaling, migratory prostate cancer cell phenotypes, and metastatic dissemination of prostate cancer in vivo in nude mice. In conclusion, we demonstrate that the cytokine IL-6 directly promotes prostate cancer metastasis in vitro and in vivo via Jak-Stat3 signaling pathway, and that IL-6-driven metastasis can be effectively suppressed by pharmacologic targeting of Jak1/2 using Jak1/2 inhibitor AZD1480. Our results therefore provide a strong rationale for further development of Jak1/2 inhibitors as therapy for metastatic prostate cancer.<br />
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2. Clin Cancer Res. 2013 Oct 15;19(20):5658-74. doi: 10.1158/1078-0432.CCR-13-0422. Epub 2013 Aug 13.<br />
Pharmacologic inhibition of Jak2-Stat5 signaling By Jak2 inhibitor AZD1480 potently suppresses growth of both primary and castrate-resistant prostate cancer.<br />
Gu L(1), Liao Z, Hoang DT, Dagvadorj A, Gupta S, Blackmon S, Ellsworth E, Talati P, Leiby B, Zinda M, Lallas CD, Trabulsi EJ, McCue P, Gomella L, Huszar D, Nevalainen MT.<br />
Author information:<br />
(1)Authors' Affiliations: Departments of Cancer Biology, Urology, Pathology, and Medical Oncology, Kimmel Cancer Center; Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania; and Oncology iMED, AstraZeneca R&D Boston, Waltham, Massachusetts.<br />
PURPOSE: Progression of prostate cancer to the lethal castrate-resistant stage coincides with loss of responsiveness to androgen deprivation and requires development of novel therapies. We previously provided proof-of-concept that Stat5a/b is a therapeutic target protein for prostate cancer. Here, we show that pharmacologic targeting of Jak2-dependent Stat5a/b signaling by the Jak2 inhibitor AZD1480 blocks castrate-resistant growth of prostate cancer. EXPERIMENTAL DESIGN: Efficacy of AZD1480 in disrupting Jak2-Stat5a/b signaling and decreasing prostate cancer cell viability was evaluated in prostate cancer cells. A unique prostate cancer xenograft mouse model (CWR22Pc), which mimics prostate cancer clinical progression in patients, was used to assess in vivo responsiveness of primary and castrate-resistant prostate cancer (CRPC) to AZD1480. Patient-derived clinical prostate cancers, grown ex vivo in organ explant cultures, were tested for responsiveness to AZD1480. RESULTS: AZD1480 robustly inhibited Stat5a/b phosphorylation, dimerization, nuclear translocation, DNA binding, and transcriptional activity in prostate cancer cells. AZD1480 reduced prostate cancer cell viability sustained by Jak2-Stat5a/b signaling through induction of apoptosis, which was rescued by constitutively active Stat5a/b. In mice, pharmacologic targeting of Stat5a/b by AZD1480 potently blocked growth of primary androgen-dependent as well as recurrent castrate-resistant CWR22Pc xenograft tumors, and prolonged survival of tumor-bearing mice versus vehicle or docetaxel-treated mice. Finally, nine of 12 clinical prostate cancers responded to AZD1480 by extensive apoptotic epithelial cell loss, concurrent with reduced levels of nuclear Stat5a/b. CONCLUSIONS: We report the first evidence for efficacy of pharmacologic targeting of Stat5a/b as a strategy to inhibit castrate-resistant growth of prostate cancer, supporting further clinical development of Stat5a/b inhibitors as therapy for advanced prostate cancer.<br />
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3. Oncologist. 2013;18(7):819-20. doi: 10.1634/theoncologist.2013-0198. Epub 2013 Jul 11.<br />
AZD1480: a phase I study of a novel JAK2 inhibitor in solid tumors.<br />
Plimack ER(1), Lorusso PM, McCoon P, Tang W, Krebs AD, Curt G, Eckhardt SG.<br />
Author information:<br />
(1)Fox Chase Cancer Center, Temple Health, Philadelphia, Pennsylvania 19111, USA. [email protected]<br />
BACKGROUND: AZD1480 is a novel agent that inhibits Janus-associated kinases 1 and 2 (JAK1 and JAK2). The primary objective of this phase I study was to investigate the safety and tolerability of AZD1480 when administered as monotherapy to patients with solid tumors.<br />
METHODS: Thirty-eight patients with advanced malignancies were treated at doses of 10-70 mg once daily (QD) and 20-45 mg b.i.d.<br />
RESULTS: Pharmacokinetic (PK) analysis revealed rapid absorption and elimination with minimal accumulation after repeated QD or b.i.d. dosing. Exposure increased in a dose-dependent manner from 10-50 mg. Maximum plasma concentration (Cmax) was attained ∼1 hour after dose, and t1/2 was ∼5 hours. Pharmacodynamic analysis of circulating granulocytes demonstrated maximum phosphorylated STAT3 (pSTAT3) inhibition 1-2 hours after dose, coincident with Cmax, and greater pSTAT3 inhibition at higher doses. The average pSTAT3 inhibition in granulocytes at the highest dose tested, 70 mg QD, was 56% (standard deviation: ±21%) at steady-state drug levels. Dose-limiting toxicities (DLTs) consisted of pleiotropic neurologic adverse events (AEs), including dizziness, anxiety, ataxia, memory loss, hallucinations, and behavior changes. These AEs were generally reversible with dose reduction or treatment cessation.<br />
CONCLUSIONS: Whether the DLTs were due to inhibition of JAK-1/2 or to off-target effects is unknown. The unusual DLTs and the lack of clinical activity led to discontinuation of development.<br />
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4. Blood Cancer J. 2011 Dec;1(12):e46. doi: 10.1038/bcj.2011.46. Epub 2011 Dec 2.<br />
The JAK inhibitor AZD1480 regulates proliferation and immunity in Hodgkin lymphoma.<br />
Derenzini E, Lemoine M, Buglio D, Katayama H, Ji Y, Davis RE, Sen S, Younes A.<br />
Aberrant activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway has been reported to promote proliferation and survival of Hodgkin and Reed-Sternberg cells of Hodgkin lymphoma (HL). We investigated the activity of the JAK inhibitor AZD1480 in HL-derived cell lines and determined its mechanisms of action. AZD1480 at low doses (0.1-1 μ) potently inhibited STATs phosphorylation, but did not predictably result in antiproliferative effects, as it activated a negative-feedback loop causing phosphorylation of JAK2 and extracellular signal-regulated kinases 1 and 2 (ERK1/2), and increased IP-10, RANTES and interleukin (IL)-8 concentrations in the supernatants. Inhibition of the ERK activity by mitogen-activated extracellular signal regulated kinase (MEK) inhibitors (UO126 and PD98059) enhanced the cytotoxic activity of AZD1480. Interestingly, submicromolar concentrations of AZD1480 demonstrated significant immunoregulatory effects by downregulating T-helper 2 cytokines and chemokines, including IL-13 and thymus- and activation-regulated chemokine, and the surface expression of the immunosuppressive programmed death ligands 1 and 2. Higher concentrations of AZD1480 (5 μ) induced G2/M arrest and cell death by inhibiting Aurora kinases. Our study demonstrates that AZD1480 regulates proliferation and immunity in HL cell lines and provides mechanistic rationale for evaluating AZD1480 alone or in combination with MEK inhibitors in HL.<br />
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