Tumor-specific anti-angiogenic anti-CD70-FGF/VEGF-trap fusion antibodies for renal cancer therapy

项目摘要 肾细胞癌（Renal cell carcinoma，RCC）是一种致死性疾病，其发病率呈上升趋势.它被分为各种 RCC是透明细胞RCC（ccRCC）亚型，占所有RCC肿瘤的约85%。电流靶向分子 包括酪氨酸激酶抑制剂（TKI）在内的治疗策略， ccRCC患者的总体生存率显著提高。尽管治疗取得了进展， 只有少数几个案件得到了持久的答复。晚期乳腺癌治疗方法的前景 近年来，由于在发展 免疫药物。靶向VEGF和免疫疗法的组合已经显示出显著的 临床前景，并打开了治愈这种致命疾病的可能性。然而，这种疗法也 产生额外的毒性，范围从中度到不良，需要中断或减少剂量， 从而限制了功效。另一个因素，限制了VEGF靶向治疗晚期乳腺癌的成功， ccRCC是均匀发展的抗性。多项研究揭示了成纤维细胞的关键作用 生长因子-2（FGF 2）在晚期ccRCC耐药发展中的作用，无论TKI或 抗VEGF/VEGFR 2抗体用作抗VEGFR剂。因此，我们首次设计了， 一类新型的双陷阱肽（F/V陷阱），阻断两种生物学上不同的促血管生成途径， VEGFR和FGFR依赖性，对ccRCC进展至关重要。通过将我们的F/V陷阱融合到抗-HCV的Fab片段， 为了进一步研究抗CD 70抗体的作用，我们研制了一种新的三特异性抗CD 70-FGF/VEGF Trap融合抗体（F/V-trap FA）。 该抗体同时结合在ccRCC中特异性表达的配体CD 70，并中和两者， VEGF-A和FGF 2细胞因子。预期通过中和FGF 2，一种关键的替代促血管生成细胞因子， F/V-trap FA将预防或至少显著延迟抗VEGF/VEGFR耐药性的发展。 治疗晚期ccRCC。重要的是，VEGF-和FGF-细胞因子家族的肿瘤内消耗通过 预计F/V-trap FA将克服由使用F-TRAP观察到的脱靶VEGF/VEGFR抑制引起的副作用。 全身性抗血管生成方法。拟议的研究将检验新的双特异性F/V- 捕集剂FA与现有的VEGF中和剂相比具有两个主要优点。通过靶向FGF/VEGF陷阱， 在肿瘤中，它将：（i）实现FGF/VEGF陷阱的更高的肿瘤内浓度;（ii）克服FGF 2- 在晚期ccRCC中介导对常规抗血管生成疗法的抗性的发展;和（iii）限制 由全身性抗VEGF方法观察到的脱靶VEGFR抑制引起的副作用。来测试我们 假设和验证F/V-trap FA的治疗价值，我们提出以下具体目的：（1） 具有上级FGF/VEGF的领先F/V-trap FA衍生物的开发、鉴定和表征 （2）使用抗VEGFR TKI-1在体内检测F/V-trap FA的抗血管生成功效。 RCC的耐药PDX小鼠模型。

PROJECT SUMMARY Renal cell carcinoma (RCC) is a lethal disease whose incidence is on the rise. It is categorized into various subtypes, with clear cell RCC (ccRCC) representing about 85% of all RCC tumors. Current targeted molecular strategies, including tyrosine kinase inhibitors (TKIs), have resulted in a doubling of progression-free survival and significant gains in overall survival in ccRCC patients. Despite the therapeutic progress, complete and durable responses have been noted in only a few cases. The landscape of therapeutic approaches for advanced RCC has expanded rapidly in recent years as a result of significant progress in the development of immunotherapeutic drugs. The combination of VEGFR-targeting and immunotherapies have shown significant clinical promise and opened the possibility of a cure for this lethal disease. However, such therapies have also conferred additional toxicities ranging from moderate to adverse, requiring dose interruptions or reductions, thereby limiting the efficacy. Another factor, limiting the success of VEGFR-targeting therapy of advanced ccRCC, is the resistance which uniformly develops. Multiple studies have revealed the key role of fibroblast growth factor-2 (FGF2) in the development of resistance in advanced ccRCC, irrespective of whether TKIs or anti-VEGF/VEGFR2 antibodies were used as anti-VEGFR agents. Therefore, we have designed for the first time, a novel class of dual-trap peptides (F/V traps), to block two biologically distinct pro-angiogenic pathways, VEGFR- and FGFR-dependent, critical for ccRCC progression. By fusion of our F/V trap to Fab fragment of anti- CD70 antibody, we have developed a new tri-specific anti-CD70-FGF/VEGF Trap fusion antibody (F/V-trap FA). This antibody does simultaneously bind CD70, a ligand, specifically expressed in ccRCC, and neutralize both, VEGF-A and FGF2 cytokines. It is expected that by neutralizing FGF2, a key alternative pro-angiogenic cytokine, F/V-trap FA will prevent or at least significantly delay the development of resistance to anti-VEGF/VEGFR therapy in advanced ccRCC. Importantly, the intra-tumoral depletion of VEGF- and FGF- cytokine families by F/V-trap FA is anticipated to overcome side-effects arising from off-target VEGF/VEGFR inhibition seen with systemic anti-angiogenic approaches. The proposed studies will test the hypothesis that novel bi-specific F/V- trap FA have two major advantages over existing VEGF-neutralizing agents. By targeting the FGF/VEGF trap to tumors, it will: (i) achieve higher intra-tumoral concentrations of the FGF/VEGF Trap; (ii) overcome FGF2- mediated development of resistance to conventional anti-angiogenic therapy in advanced ccRCC; and (iii) limit side-effects arising from off-target VEGFR inhibition seen with systemic anti-VEGF approaches. To test our hypothesis and to validate the therapeutic value of F/V-trap FA, we propose the following Specific Aims: (1) Development, identification and characterization of the leading F/V-trap FA derivative with superior FGF/VEGF neutralizing activity; (2) To examine the anti-angiogenic efficacy of F/V-trap FA in vivo using anti-VEGFR TKI- resistant PDX mouse models of RCC.