Targeting Casein Kinase 1d/e (CK1d/1e) in Cancer Therapeutics

描述(由申请人提供)：我们研究团队的目标是优化和评估酪蛋白激酶1(CK1δ/ϵ)的β和β亚型的抑制剂。CK1DNA是一种单体丝氨酸/苏氨酸蛋白激酶，调节多种细胞过程，包括δ/ϵ信号、DNA损伤反应和昼夜节律。CK1δ/ϵ的异常调控与多种癌症、神经退行性疾病和睡眠障碍有关。重要的是，我们的研究团队将药物和合成有机化学方面的专业知识和新疗法的派生专业知识(Pi William Roush博士)、癌症遗传学和临床前治疗研究方面的专业知识(约翰·克利夫兰博士共同)以及药物开发和抗癌激酶疗法的专业知识(Derek Duckett博士)结合在一起，证明了我们新型的内部高选择性和竞争性的CK1δ/ϵ抑制剂具有非常低的纳米分子生化和抗癌(黑色素瘤、乳腺癌和胶质母细胞瘤)细胞效力。此外，对黑色素瘤和三阴性乳腺癌细胞的体外遗传学研究表明，我们的化合物的抗肿瘤活性与抑制CK1δ/ϵ活性是一致的，初步的原位异种移植研究表明，我们的CK1δ/ϵ抑制剂在体内具有强大的抗黑色素瘤和抗基底膜活性。此外，NCI-60筛查和中空纤维分析表明，我们的CK1δ/ϵ抑制剂对包括结肠癌、肺癌和肾癌在内的其他人类癌症具有显著的效力。重要的是，我们的先导化合物通常没有毒性，因为这些CK1δ/ϵ抑制剂不会损害某些肿瘤类型或正常细胞的生长或存活，而且在临床前研究中，它们在21天的慢性BID剂量中耐受性很好。因此，我们假设CK1δ/ϵ亚型是癌症治疗发展的极具吸引力的靶点。在目标1中，我们的领先CK1δ/ϵ抑制剂的类药物特性--包括脑渗透--将使用反复药物化学、二甲基苯丙酮和药效筛选进行优化。我们将使用严格的研究操作计划来确定CK1δ/ϵ抑制剂的优先顺序，这些将进入AIM 2和3中概述的研究。在AIM中，我们将使用一系列遗传方法，严格测试我们的先导化合物和优化的类似物的抗癌活性是否仅仅是由于抑制CK1δ和/或CK1ϵ，或者是否其他生物相关的靶点有助于它们的效力。利用小鼠模型，我们还测试了CK1δ和/或CK1ϵ在突变型BRAF驱动的黑色素瘤发生中的作用。最后，在目标3中，TOP化合物将使用小鼠和人类黑色素瘤、人类三阴性乳腺癌以及原发人类GBM作为单一药物和与传统疗法相结合的异种移植瘤来测试其抗肿瘤效果。我们认为，我们的研究团队将产生一系列针对CK1δ/ϵ的新的、有效的和安全的抗癌药物，这些药物将作为治疗一系列耐药恶性肿瘤的广谱疗法。

DESCRIPTION (provided by applicant): The goal of our research team is to optimize and evaluate compounds that are inhibitors of the delta and epsilon isoforms of casein kinase 1 (CK1δ/ϵ). CK1δ/ϵ are monomeric serine/threonine protein kinases that regulate diverse cellular processes including Wnt signaling, the DNA damage response and circadian rhythms. Aberrant regulation of CK1δ/ϵ is implicated in various cancers, and in neurodegenerative and sleep disorders. Importantly, our research team, which combines expertise in medicinal and synthetic organic chemistry and the derivation of novel therapeutics (PI Dr. William Roush), with those in cancer genetics and preclinical therapeutic studies (co-PI Dr. John Cleveland) and drug development and anti- cancer kinase therapeutics (co-PI Dr. Derek Duckett) has demonstrated that our new in-house and highly selective and ATP competitive CK1δ/ϵ inhibitors have very low nanomolar biochemical and anti-cancer (melanoma, breast cancer and glioblastoma [GBM]) cell potency. Furthermore, ex vivo genetic studies in melanoma and triple-negative breast cancer cells indicate that the anti-tumor activity of our compounds is consistent with inhibition of CK1δ/ϵ activity and pilot orthotopic xenograft studies have shown that our CK1δ/ϵ inhibitors have potent anti-melanoma and anti-GBM activity in vivo. In addition, NCI-60 screens and hollow fiber assays have shown that our CK1δ/ϵ inhibitors have remarkable potency against other human cancers that include colon, lung and renal cancer. Importantly, our lead compounds are not generally toxic, as these CK1δ/ϵ inhibitors do not compromise the growth or survival of some tumor types or of normal cells and they are well tolerated in chronic 21 day BID dosing in pre-clinical studies. Thus, we hypothesize that the CK1δ/ϵ isoforms are highly attractive targets for the development of cancer therapeutics. In Aim 1 the drug-like properties - including brain penetration - of our lead CK1δ/ϵ inhibitors will be optimized using reiterative medicinal chemistry, DMPK, and efficacy screens. We will use a rigorous research operating plan to prioritize CK1δ/ϵ inhibitors which will flow into studies outlined in Aims 2 and 3. In Aim , using a battery of genetic approaches, we will rigorously test whether the anti-cancer activity of our lead compounds and optimized analogs is solely due to inhibition of CK1δ and/or CK1ϵ, or whether other biologically relevant targets contribute to their potency. Using mouse models we also test the roles of CK1δ and/or CK1ϵ in the development of mutant BRaf-driven melanoma. Finally, in Aim 3, top compounds will be tested for their anti-tumor efficacy using xenografts of mouse and human melanoma, human triple negative breast cancer, and of primary human GBM both as single agents and in combination with conventional therapies. We submit that our research team will generate a cast of new, potent and safe anti-cancer agents targeting CK1δ/ϵ that will be useful as broad-spectrum therapeutics against a host of resistant malignancies.