Abstract 1797: Preclinical evaluation of HM-018, a potent and selective JAK inhibitor in the treatment of myloproliferative disorders

Autor: Weihua Gu, Weiguo Su, Wei Deng, Zhixiang Zhang, Helen Zhao, Weiguo Qing, Shiming Fan, Yang Sai, Xiaoning Yang, James Yan, Wuzhong Shen, Jia Li, Youjun Yu, Jing Wang, Yongxin Ren
Rok vydání: 2012
Předmět:
Zdroj: Cancer Research. 72:1797-1797
ISSN: 1538-7445
0008-5472
Popis: JAK2 kinase mutation V617F is prevalent in myeloproliferative diseases (MPD), including polycythemia vera (PV, 81-99%), essential thrombocytosis (ET, 41-72%) and primary myelofibrosis (PMF, 39-57%). This point mutation constitutively activates the JAK kinase and leads to oncogenic potential of host cells, and thus making JAK2 a promising molecular target for MPD therapy. HM-018 is a small molecule inhibitor against JAK kinase and the compound's preclinical anti-MPD effects from signal transduction to biological consequences were investigated. HM-018 was found to inhibit JAK kinase 1, 2, 3 and TYK with IC50 of 0.010, 0.006, 0.040 and 0.047 μM, respectively. The compound demonstrated >100 folds selectivity against a panel of 63 kinases. In accordance with enzymatic activity, HM-018 suppressed ligand dependent or constitutive JAK activation in multiple cell lines as evidenced by the decrease of STAT3/5 phosphorylation. As a result, JAK dependent cell proliferation was significantly inhibited by HM-018. EPO-mediated mouse PV model was utilized to evaluate the in vivo efficacy of the compound. HM-018 could shrink enlarged mouse spleen, a typical symptom of PV, in a dose dependent manner accompanied with decreased STAT5 phosphorylation both in animal spleen and in bone marrow after oral dosing for 7 days. To better mimic MPD development in a more clinically-relevant manner, JAK2-V617F-tranfected 32D cells were injected into mice intravenously, and it was observed that oral treatment of HM-018 not only prolonged the animal's life span, but also reduced MPD-related symptoms, such as spleen weight increase and organ invasion by malignant cells. Meanwhile, HM-018 exhibited a favorable pharmacokinetic profile and acceptable safety window in rats. Based on the preclinical data, HM-018 demonstrated anti-MPD potency both in vitro and in vivo, and the studies have provided rationale to further develop this compound as possible MPD therapeutics. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1797. doi:1538-7445.AM2012-1797
Databáze: OpenAIRE