Anti-Angiogenic and Tumorcidal Drugs Against Lung Carcinoma

描述（由申请人提供）：肺癌是世界上癌症死亡的主要原因，传统疗法的疗效非常有限。因此，新的治疗方法来改善这种疾病的结果是至关重要的。鉴于受体酪氨酸激酶在肿瘤生长、侵袭、转移和血管生成中起着重要作用，肿瘤细胞生物学的最新进展使人们对开发靶向受体酪氨酸激酶的新疗法重新产生了兴趣和高度乐观。特别是c-Met，肝细胞生长因子/分散因子（HGF/SF）的受体酪氨酸激酶，已被确定为抗肿瘤发生的治疗靶点。c-Met在多种实体瘤中过表达或突变。有强有力的证据表明，c-Met在肺癌细胞系和肿瘤组织中过度表达、激活，有时甚至发生突变。SF/HGF与其受体的结合不仅促进肿瘤细胞的生长，而且还促进肿瘤新生血管内皮细胞的生长。c-Met-SF/HGF通路的拮抗是一种有吸引力的肿瘤杀灭和抗血管生成途径，这种双向机制可能降低治疗诱导的耐药发生率。我们的初步研究已经确定了ANG-797，一种活性的小分子激酶抑制剂，与ATP竞争c-Met的ATP结合位点。令人鼓舞的结果表明，ANG-797显著且选择性地抑制c-Met活化，抑制SF/HGF引发的下游信号事件。在体外，ANG-797抑制内皮细胞和肿瘤细胞的生长以及SF/ hgf诱导的血管生成。体内实验数据显示，口服或口服ANG-797对原位植入脑肿瘤的动物有显著的生存益处。最近的研究表明，ANG-797还能抑制与血管生成相关的另一种RTK的活性，并且该化合物对这些RTK的双重抑制活性可能是体内高水平抗肿瘤活性的原因，尽管对单个肿瘤生长相关的RTK靶点的体外ic50很高。我们认为，通过合理修饰2,4-二氨基喹啉支架上的取代基，可以提高ANG-797的效价。最近，我们利用分子模拟和药物化学方法，合成了103个新的ANG-797类似物：37个2位类似物和66个4位修饰类似物。这些修饰允许这一系列化合物的扩展，并有可能显著降低针对激酶靶点的IC50。在较新的化合物中，ANG-1490和ANG-2201在我们基于细胞的筛选试验中对这两个靶点的效力都有所提高。有趣的是，我们的试点体内研究表明，ANG-1490和ANG-2201对皮下NSCLC A549肿瘤有效。在目前的应用中，我们拟在多个筛选中证实ANG-1490和ANG-2201的选择性和效力水平的提高，并充分评价这些化合物对肺癌细胞系增殖和信号转导的抗肺癌作用。此外，我们正在进行的化学项目中出现的任何具有相同或更好的效力和选择性的新类似物将包括在这些评估中。我们还将确定最小有效剂量并更好地了解体外作用机制。拟议的体内研究将为这些抗血管生成和肿瘤杀灭药物在小鼠模型中抑制肺肿瘤生长和延长生存期的能力提供重要的临床前疗效数据。这些初步研究将支持正在进行的新药开发，对迫切需要更好干预的疾病具有潜在的临床益处。肺癌的高死亡率和缺乏有效的治疗强调需要新的治疗方法。c-Met小分子抑制剂作为抗肿瘤和抗血管生成药物在人肺癌的治疗中具有重要的治疗潜力。

DESCRIPTION (provided by applicant): Lung cancer is the world's leading cause of cancer deaths, with conventional therapies offering very limited benefit. Therefore, novel therapeutic approaches to improve outcomes of this disease are critical. Recent advances in tumor cell biology have led to renewed interest and heightened optimism in the development of new therapeutics targeting receptor tyrosine kinases, given their essential roles in tumor growth, invasion, metastasis and angiogenesis. In particular, c-Met, the receptor tyrosine kinase for hepatocyte growth factor/scatter factor (HGF/SF), has been identified as a therapeutic target against tumorigenesis. c-Met is over-expressed or mutated in a variety of solid tumors. There is strong evidence that c-Met is overexpressed, activated, and sometimes mutated in lung cancer cell lines and tumor tissues. Binding of SF/HGF to its receptor promotes growth not only of tumor cells, but also of the endothelial cells lining the tumor neovasculature. Antagonism of the c-Met-SF/HGF pathway represents an attractive tumoricidal and anti- angiogenic approach and such a bi-faceted mechanism potentially can lower the incidence of therapy-induced resistance. Our preliminary studies have identified ANG-797, an active, small molecule kinase inhibitor that competes with ATP for the ATP-binding site of c-Met. Encouraging results indicate that ANG-797 significantly and selectively inhibits c-Met activation and inhibits downstream signaling events initiated by SF/HGF. In vitro, ANG-797 inhibits endothelial and tumor cell growth and SF/HGF-induced angiogenesis. In vivo data reveal a significant survival benefit to animals bearing orthotopically implanted brain tumors after i.p. or oral administration of ANG-797. Recent studies have demonstrated that ANG-797 also inhibits activity of a second RTK associated with angiogenesis, Tie-2, and the dual inhibitory activities of the compound towards these RTKs may account for the high level of anti-tumor activity in vivo despite high nanomolar in vitro IC50s towards the individual tumor growth-related RTK targets. We believe that the potency of ANG-797 can be improved by rationally modifying substituents on its 2,4-diaminoquinazoline scaffold. Recently, by using molecular modeling and medicinal chemistry approaches, we have generated 103 new ANG-797 analogs: thirty-seven 2- positional analogs and Sixty-six modified at the 4-position. These modifications allow expansion of this series of compounds and the potential to significantly decrease the IC50 against the kinase targets. Among the newer compounds, ANG-1490 and ANG-2201 have increased potency against both targets in our cell-based screening assays. Interestingly, our pilot in vivo studies suggest that ANG-1490 and ANG-2201 are efficacious against subcutaneous NSCLC A549 tumors. In the current application, we propose to confirm the improved levels of selectivity and potency of ANG-1490 and ANG-2201 in multiple screens, and fully evaluate the anti-lung cancer effects of these compounds on the proliferation and signal transduction in lung cancer cell lines. In addition, any newer analogs emerging from our ongoing chemistry program with the same or better potency and selectivity will be included in these evaluations. We will also determine the minimal effective dose and better understand the mechanism of action in vitro. The proposed in vivo studies will provide important preclinical efficacy data regarding the ability of these anti-angiogenic and tumorcidal agents to inhibit lung tumor growth and prolong survival in mouse models. These initial studies will support the ongoing development of a new drug with potential clinical benefits to a disease urgently needing better interventions. The high death rate of lung cancer and the lack of an effective therapy stress the need for novel therapeutics. Small molecule inhibitors against c-Met as anti-tumor and anti-angiogenic agents have important therapeutic potential for the treatment of human lung carcinoma.