Biomarker-Driven Src Inhibitor Studies in Colorectal Cancer Patients

描述（由申请人提供）：结直肠癌是每年癌症死亡的第二大原因，2009年估计有超过49，920例死亡。尽管在过去十年中有多种新的FDA批准的治疗方法，但5年生存率仍然非常低。此外，尽管人们对“靶向”患者掺入KRAS基因密码子12/13测试EGFR靶向抗体感到兴奋，但这一发现是在FDA批准这些药物5年后，导致数十亿美元（以及副作用）的浪费“治疗”那些有0%机会获益的患者。迫切需要新的方法和新的疗法。为此，已经创建了患者来源的结直肠癌人外植体异种移植模型，以帮助开发结直肠癌的新疗法。一个有前途的药物靶点是非受体激酶Src。这种蛋白质调节影响细胞粘附、迁移和侵袭的多个级联反应，这些因素在失调时使肿瘤细胞能够破坏其微环境，不依赖于正常的调节信号而移动到远处并侵入宿主组织。这种表型的结果是转移，这是癌细胞引起器官功能障碍并最终死亡的关键机制。 我们已经发现了一个子集的人结直肠肿瘤细胞系和外植体敏感的Src抑制。使用基因测序，基因微阵列（最高评分对分析），和FISH，我们已经开发了一个假定的综合基因组预测，选择敏感的肿瘤/患者开始治疗之前。下一步是在扩大的临床前试验（包括一种新的小鼠肝转移模型）中完善预测因子，并进行两阶段的II期临床试验。我们已经组建了一个由国家认可的Src抑制剂和临床生物标志物开发专家组成的团队，他们完全有资格进行这项工作。 目的是证明使用存档肿瘤组织，接受saracatinib治疗的生物标志物阳性患者队列的缓解/非进展率高于同时入组的生物标志物阴性患者。我们还将对一部分患者进行系列肿瘤活检，以探索Src抑制剂在肿瘤水平的作用。该临床试验代表了一个非常独特的机会，可以鉴定和扩展结直肠癌人类异种移植实验的结果，以进行可能的III期试验。我们还期望该数据集成为开发Src抑制剂合理组合研究的丰富来源。此外，关于人类外植体异种移植物模型的效用也有更广泛的影响，目前正在地球仪的许多癌症类型中探索，作为癌症临床的模拟器。

DESCRIPTION (provided by applicant): Colorectal cancer is the second leading cause of cancer deaths annually, with over 49,920 deaths estimated for 2009. Despite multiple new FDA-approved therapies in the last decade, the 5-year survival remains extremely poor. In addition, although there has been much excitement about "targeted" patients with the incorporation of KRAS gene codon 12/13 testing for EGFR-targeting antibodies, this discovery came 5 years after the FDA approval of these drugs, resulting in the waste of billions of dollars (as well as side effects) "treating" patients who had a 0% chance of benefit. New approaches, as well as new therapies, are desperately needed. To this end, a patient-derived colorectal cancer human explant xenograft model has been created to help develop novel therapies for colorectal cancer. A promising drug target is the non-receptor kinase, Src. This protein regulates multiple cascades that impact cellular adhesion, migration and invasion, factors that when dysregulated enable tumor cells to disrupt their microenvironment, travel to distant sites and invade host tissues independent of normal regulatory signals. The result of this phenotype is metastasis, the critical mechanism by which cancer cells cause organ dysfunction and ultimately death. We have discovered a subset of human colorectal tumor cell lines and explants sensitive to Src inhibition. Using gene sequencing, gene micro-array (top scoring pairs analysis), and FISH, we have developed a putative integrated genomic predictor to select sensitive tumors/patients prior to initiating therapy. The next steps are to refine the predictor in expanded preclinical testing (including a novel mouse liver metastases model) as well as conduct a two-stage phase II clinical trial. We have assembled a team of nationally recognized experts in Src inhibitors and clinical biomarker development who are well-qualified to perform this work. The goal is to demonstrate that using archival tumor tissue, a cohort of biomarker-positive patients treated with saracatinib will have a higher response/nonprogression rate than a simultaneously enrolled group on biomarker-negative patients. We will also perform serial tumor biopsies on a subset of patients to explore Src inhibitor effects at the tumoral level. The clinical trial represents a highly unique opportunity to qualify and extend the results of the human xenograft experiments in colorectal cancer for possible phase III testing. We also expect this dataset to be a rich source with which to develop rational combination studies with Src inhibitors. Moreover, there are also broader implications with regard to the utility of human explant xenograft models, currently being explored across the globe in many cancer types, as simulators of the cancer clinic.