Tumor caveolae-targeted systemic therapy of breast cancer with antibody drug conjugates

乳腺癌是女性最常见的癌症，也是第二大致死原因。 在女人中间。尽管在分子理解和个性化治疗方面取得了重大进展 乳腺癌，这种疾病处于进展性转移阶段，仍然无法治愈，可供选择的治疗方法 对患者来说，只能提供适度的生存益处。现有的全身化疗的疗效仅限于 给药、进入和穿透实体肿瘤，以及对患者的毒性。因此，要发展更多 乳腺癌的有效和安全治疗，有必要实施有效的靶向给药 系统。肿瘤内皮细胞表面的小凹作为一种跨内皮细胞转运系统 主动地将血液循环中的靶向抗体注入肿瘤组织。我们的发现支持这一点 靶向小窝提供了一个快速泵送带有特定附着货物的靶向抗体的平台 进入乳腺肿瘤的浓度远远超过血液中的最高水平。使用这些最新的 发现，我们打算靶向抗体药物结合物(ADC)的DM1美坦辛，最有效的之一 靶向肿瘤内皮腔内膜联蛋白A1截短型的抗癌药物 强大的治疗效果，在乳腺肿瘤内。我们已经证明了AnnA1在 人类肿瘤的血管系统和小窝。最近，我们已经产生了针对AnnA1的人源化抗体 (HAnnA1)和我们的初步实验显示乳腺癌对 HAnnA1与DM1结合(hAnnA1-DM1 ADC)。我们假设通过注射有针对性的抗体 随着DM1药物进入乳腺肿瘤，小凹可以迅速和特异地积累这种治疗剂。 在肿瘤内部，导致肿瘤破坏，毒性显著降低。我们提出以下具体目标： 目的1.产生ADC并对其进行表征。我们将与DM1药物共价制备一系列偶联物 使用不可切割和可切割接头连接到hAnnA1抗体上。基于AIM2中的筛选，我们 将产生具有选择连接子化学的THIOMAB hAnnA1。 目的2.筛选最佳连接子化学、生产、验证和药代动力学分析 肿瘤血管小窝靶向DM1-THIOMAB-ADC在乳腺癌啮齿动物模型中的作用这些 研究将能够实现最佳的连接子化学，以开发具有DM1位点特异性连接的ADC。 目的3.评价肿瘤血管小窝靶向DM1ADC的治疗效果 乳腺癌的临床相关模型。临床相关原位模型的治疗研究 乳腺癌，包括植入人乳房的人肿瘤球体活体显微镜模型 组织和患者来源的乳腺癌异种移植，包括三阴性和HER2+模型，将提供 评估新型hAnnA1-DM1 ADC疗法的平台。拟议的项目将有助于建立框架 用于临床翻译肿瘤-小凹靶向ADC治疗乳腺癌。

Breast cancer is the most commonly diagnosed cancer in women and is a second leading cause of death among woman. Despite the significant progress in molecular understanding and personalized therapies of breast cancer, this disease in progressed metastatic stage remains incurable and treatment options available to patients provide only modest survival benefit. Efficacy of existing systemic chemotherapy is limited in delivery, access and penetration into solid tumors, as well as by toxicity to patients. Thus, to develop more effective and safer therapies of breast cancer, it is necessary to implement an efficient targeted drug delivery system. Caveolae at the surface of tumor endothelial cells act as a transendothelial transport system that actively pumps targeted antibodies from the blood circulation into the tumor tissue. Our findings support that targeting caveolae provides a platform for rapid pumping of targeted antibodies with attached cargo specifically into breast tumors at concentrations greatly exceeding maximum levels in the blood. Using these recent findings, we intend to target antibody drug conjugates (ADC) of DM1 maytansinoid, one of the most potent anticancer drugs to target truncated form of Annexin A1 in tumor endothelial caveolae in order to deliver this powerful therapeutic effectively inside of breast tumors. We have demonstrated that AnnA1 is expressed in the vasculature and caveolae of human tumors. Recently, we have generated humanized antibody against AnnA1 (hAnnA1) and our preliminary experiments demonstrate strong therapeutic response of breast cancer to hAnnA1 conjugated to DM1 (hAnnA1-DM1 ADC). We hypothesize that by pumping targeted antibodies armed with DM1 drug into breast tumors, caveolae can rapidly and specifically accumulate this therapeutic agent inside tumors, leading to tumor destruction with significantly reduced toxicity. We propose these Specific Aims: Aim 1. To generate and characterize ADCs. We will prepare series of conjugates with DM1 drug covalently attached to hAnnA1 antibody using non-cleavable and cleavable linkers. Based on the screening in Aim2, we will generate THIOMAB hAnnA1 with select linker chemistry. Aim 2. Screening for optimal linker chemistry, production, validation and pharmacokinetic analysis of tumor vascular caveolae-targeted DM1 THIOMAB ADC in rodent tumor model of breast cancer. These studies will enable implementing optimal linker chemistry to develop ADC with site-specific attachment of DM1. Aim 3. Evaluation of therapeutic efficacy of the tumor vascular caveolae-targeted DM1 ADCs in clinically-relevant models of breast cancer. Therapeutic studies in clinically-relevant orthotopic models of breast cancer, including intravital microscopy model of human tumor spheroids engrafted into human breast tissue, and patient-derived breast cancer xenografts, including triple-negative and HER2+ models, will provide platform to evaluate novel hAnnA1-DM1 ADC therapy. The proposed project will help to establish framework for clinical translation of tumor-caveolae targeted ADC for treatment of breast cancer.