Lead Optimization of Novel Inhibitors of the Thioesterase Domain of FASN

描述(由申请人提供)：本R01申请名为“脂肪酸合成酶硫酯酶结构域抑制物的先导优化”，是对PAR-12-060“发现体内化学探针验证命中的征集”的回应。代谢重联现在被认为是癌症的标志之一，可以在中枢碳代谢的许多子网络中观察到。在实体肿瘤中，脂肪生成亚网络经常上调，脂肪酸合成酶(FASN)的表达和活性增加是许多肿瘤细胞生存和增殖所必需的，包括前列腺癌、乳腺癌、结肠癌、卵巢和肝脏。对于这项提议来说，重要的是，FASN的明确作用最近已经在恶性黑色素瘤中确立，恶性黑色素瘤是一种威胁生命的皮肤癌。因此，抑制FASN是治疗多种非常严重的癌症，特别是黑色素瘤的一种有前途的方法。我们最近通过MLPCN程序筛选了针对FASN硫酯酶(TE)结构域的360K化合物，并鉴定了几个被证明是易处理的小分子撞击。特别是，一种支架产生了一系列具有良好体内特性的类似物。该系列中最先进的化合物是一种高效、高选择性的FASN-TE体外抑制剂，可阻断整个细胞的脂肪酸生物合成，阻止肿瘤细胞增殖，对正常细胞无毒，在小鼠体内单次全身给药(10 mg/kg ip)后显示出有希望的药物水平。然而，高蛋白结合力、较差的水溶解性和较低的微球稳定性表明，必须优化其药代动力学性质，以提供适合于体内概念验证实验的化合物。这些化合物准备进行全面的化学优化，为体内概念验证研究提供准备的先导化合物。因此，我们的具体目标是：1.设计和合成具有体内口服活性的优化FASN-TE抑制剂。2.在相关的体外和细胞检测中评价FASN-TE抑制剂的效力和选择性。3.用体外ADME/T和体内药代动力学(PK)法评价FASN-TE抑制剂。4.检测铅FASN-TE抑制剂探针在相关小鼠致瘤(异种移植)模型中的作用。FASN-TE抑制剂的产生将为验证抑制FASN是有效杀死肿瘤细胞的方法的假说提供强有力的工具，同时为未来开发一类治疗癌症的新型药物奠定基础。

DESCRIPTION (provided by applicant): This R01 application entitled "Lead Optimization of Inhibitors of the Thioesterase Domain of Fatty Acid Synthase" is in response to PAR-12-060 "Solicitation of Validated Hits for the Discovery of in vivo Chemical Probes". Metabolic re-wiring is now recognized as one of the hallmarks of cancer and can be observed in many sub-networks of central carbon metabolism. The lipogenic sub-network is often up-regulated in solid tumors, and increased expression and activity of fatty acid synthase (FASN) is required for the survival and proliferation of many tumor cells, including prostate, breast, colon, ovaries, and liver. Importantly for this proposal, a clear role for FASN has recently been established in malignant melanoma, a life-threatening form of skin cancer. Thus, inhibition of FASN is a promising approach for the treatment of multiple very serious forms of cancer, and especially melanoma. We recently screened 360K compounds against the thioesterase (TE) domain of FASN through the MLPCN program and identified several small molecule hits that proved to be tractable. In particular, one scaffold yielded a family of analogues with promising in vivo properties. The most advanced compound from this series is a potent and highly selective inhibitor of FASN-TE in vitro, blocks fatty acid biosynthesis in whole cells, halts tumor cell proliferation, is non-toxic in normal cells, and shows promising drug levels in mice following a single systemic dose (10 mg/kg i.p.). However, high protein binding, poor aqueous solubility and low microsomal stability suggest that the pharmacokinetic properties must be optimized to provide compounds suitable for in vivo proof-of-concept experiments. These compounds are ready for full- scale chemistry optimization to provide lead compounds ready for in vivo proof-of-concept studies. Therefore our Specific Aims are: 1. Design and synthesize optimized FASN-TE inhibitors that are orally active in vivo. 2. Assess potency and selectivity of FASN-TE inhibitors in relevant in vitro and cellular assays. 3. Evaluate FASN-TE inhibitors using in vitro ADME/T and in vivo pharmacokinetic (PK) assays. 4. Determine efficacy of lead FASN-TE inhibitor probes in relevant mouse tumorigenic (xenograft) models. The FASN-TE inhibitors generated will provide powerful tools for testing the hypothesis that inhibition of FASN is an effective method for killing tumor cells, while laying a foundation for future development of a novel class of medications for the treatment of cancer.