Synergistic Targeted Therapy of Antibody-Drug Conjugates for Triple-Negative Breast Cancer

三阴性乳腺癌（TNBC）占所有乳腺癌的10-20%，其特征在于快速转移。 生长、转移和复发。此外，人TNBC通常在初次治疗后再生，导致 TNBC患者预后不良。TNBC的标准细胞毒性化疗具有较差的临床效果， 好处和严重的副作用。靶向治疗，如单克隆抗体（mAb）、抗体-药物 偶联物（ADC）、嵌合抗原受体工程化的T细胞和小分子抑制剂，已经被广泛应用。 开发用于治疗实体瘤，同时最大限度地减少对正常细胞的副作用，但这些疗法中没有一种 已被用于治疗TNBC。因此，靶向治疗仍然是有效治疗癌症的未满足的医疗需求。 TNBC。我们的初步研究鉴定了TNBC中的靶向表面受体（如CD 276和CD 47）， 开发了靶向TNBC但不靶向正常细胞的新型肿瘤特异性mAb， 显示出高毒性，建立了抗CD 276/CD 47 ADC的构建和评价方法， 评估了我们的ADC在体外和体内的潜在安全性和抗癌功效。我们的核心假设是 基于ADC的治疗可以通过整合抗癌药物有效地消除TNBC，副作用有限， 机制等在这项研究中，我们建议开发靶向治疗TNBC的治愈性治疗。在目标1中， 我们的目标是建立一个有效的ADC治疗平台来治疗CD 276 + TNBC，并确定最有效的 通过研究靶向特异性、ADC有效载荷介导的抗TNBC疗效和 抗CD 276 mAb诱导的免疫细胞活化和肿瘤血管生成的抑制。在目标2中，我们将 开发基于抗CD 47 ADC的靶向疗法，以消除CD 47 + TNBC，特别是化疗诱导的TNBC， CD 47 + TNBC，并防止肿瘤复发和转移。我们将研究抗肿瘤疗效， 多种TNBC细胞系和异种移植肿瘤，并描述抗TNBC机制，包括ADC- 介导的药物细胞毒性、抗CD 47 mAb依赖性细胞毒性和ADC药物的协同作用 和抗CD 47 mAb。在目标3中，我们计划使用我们建立的最大耐受剂量方案， 药代动力学，生物分布和抗肿瘤疗效，以评估我们的联合双 手术后我们的转移性同基因TNBC异种移植物模型中的靶向CD 276和CD 47的ADC，和/或 化疗如果抗癌功效在临床前模型中得到证实，这将是第一个结合 基于ADC的TNBC靶向治疗，可克服耐药性，增强细胞毒性 以低剂量作用于肿瘤细胞，限制全身毒性，防止抗原丢失复发。重要的是，我们的设计 将为潜在的转化应用建立临床治疗模型，这将改善生活质量， 与手术和/或化疗组合的TNBC患者的存活率。

Triple negative breast cancer (TNBC) comprises 10-20% of all breast cancers and is characterized by rapid growth, metastasis, and recurrence. Furthermore, human TNBC often regrows after primary treatment, leading to poor prognosis in patients with TNBC. The standard cytotoxic chemotherapies for TNBC have the poor clinical benefit and severe side effects. Targeted therapies, such as monoclonal antibodies (mAbs), antibody-drug conjugates (ADCs), chimeric antigen receptor engineered T cells and small molecule inhibitors, have been developed to treat solid tumors while minimizing the side effects on normal cells, but none of these therapies has been applied to treat TNBC. Thus, targeted therapy remains an unmet medical need to effectively treat TNBC. Our preliminary studies identified the targeting surface receptors (such as CD276 and CD47) in TNBC, developed novel tumor-specific mAbs that target TNBC but not to normal cells, tested multiple small molecules showing high toxicity, established the construction and evaluation procedures of anti-CD276/CD47 ADCs, and evaluated the potential safety and anticancer efficacy of our ADCs in vitro and in vivo. Our central hypothesis is that the ADCs-based therapy can effectively eliminate TNBC with a limited side effect via integrated anti-cancer mechanisms. In this study, we propose to develop targeted therapies for curative treatment of TNBC. In Aim 1, we aim to build an effective platform of ADC therapies to treat CD276+ TNBC, and identify the most efficient treatment strategy by investigating the targeting specificity, ADC payloads-mediated anti-TNBC efficacy, and anti-CD276 mAb-induced immune cell activation and suppression of tumor angiogenesis. In Aim 2, we will develop anti-CD47 ADC-based targeted therapies to eliminate CD47+ TNBC, especially chemotherapy-induced CD47+ TNBC, and prevent tumor recurrence and metastasis. We will investigate the anti-tumor efficacy using multiple TNBC cell lines and xenograft tumors, and delineate the anti-TNBC mechanisms, including ADC- mediated drug cytotoxicity, anti-CD47 mAb-dependent cellular cytotoxicity, and synergistic action of ADC drug and anti-CD47 mAb. In Aim 3, we plan to use our established protocols of maximal tolerated dose, pharmacokinetics, biodistribution and anti-tumor efficacy to evaluate the therapeutic values of our combined dual CD276 and CD47 targeting ADCs in our metastatic syngeneic TNBC xenograft models after surgery and/or chemotherapy. If the anti-cancer efficacy is confirmed in the preclinical models, this will be the first combined ADCs-based targeted therapy for TNBC treatment, which may overcome drug resistance, enhance cytotoxicity to tumor cells with low dose, limit systemic toxicities, and prevent antigen-loss relapse. Importantly, our designs will model clinical therapies for potential translational application, which would improve life quality and the survival rate of TNBC patients in combination with surgery and/or chemotherapy.