Antibody Therapy of Cancer

抗体治疗组旨在为肝癌和其他癌症开发新的抗体疗法。项目一：靶向glypican-3治疗肝细胞癌肝癌是世界上第五大常见癌症和第三大癌症死亡原因。肝细胞癌（HCC）约占肝癌病例的75%。胆管癌（CCA）是第二常见的原发性肝脏肿瘤。迫切需要能够成功应用于大量肝癌患者的新治疗方法。由于glypican-3 （GPC3）在HCC中的高蛋白表达，该靶点具有肝癌治疗的潜力。在FY11-12，我们通过杂交瘤技术获得了与GPC3高亲和力的YP7单克隆抗体（mAb）。在FY12，我们进行了动物实验，发现YP7在小鼠中表现出明显的肝癌异种移植肿瘤生长抑制作用。这项研究发表在《mab》杂志上，并登上了封面。正在进行的研究主要集中在探索GPC3在HCC发病机制中的作用机制，以及开发针对GPC3的人抗体用于肝癌治疗。NCI已经根据我们的GPC3单克隆抗体提交了专利申请。我们希望找到行业合作伙伴，与我们合作开发新的gpc3靶向抗体疗法来治疗肝癌。在2012财年，GPC3项目在《单克隆抗体》、《生物药物》和《癌症报告》杂志上发表了三篇论文。我们在国际研讨会上发表了我们的工作，如第二届年度PEGS抗体癌症治疗研讨会，蛋白质发现与治疗，抗体为21。项目2：靶向肝癌、间皮瘤、卵巢癌间皮素在间皮瘤、胆管癌、卵巢癌、胰腺癌、肺癌中高水平表达。在2010年，我们分析了肝癌组织中间皮素的蛋白表达，并假设间皮素是胆管癌（CCA）的潜在治疗靶点。我们与NCI的Ira Pastan合作，运用我们在噬菌体展示技术方面的专业知识，鉴定了人类间皮素特异性单克隆抗体HN1。HN1 mAb以高亲和力结合细胞表面相关的间皮素，并以优异的抗体依赖细胞介导的细胞毒性（ADCC）杀死癌细胞，有望用于治疗表达间皮素的癌症。2011财年，我们在《国际癌症杂志》上发表了HN1的研究成果。我们的间皮瘤研究项目得到了间皮瘤应用研究基金会的部分研究资助和卵巢癌研究基金的个人研究者奖给Mitchell Ho。在2012财年，我们与Ira Pastan和Dimiter Dimitrov （NCI的Frederick国家实验室）合作，通过噬菌体展示技术分离出针对间皮素的新型单域人抗体。这些人抗体可能对间皮素阳性肿瘤细胞具有新的抗肿瘤活性。NCI已经为我们用于癌症治疗的间皮素抗体提交了专利申请。NCI还将我们实验室开发的LMB-H226-GL间皮瘤模型作为研究工具提供给科学界。项目三：建立体外肿瘤球体，研究抗体治疗。大多数抗癌药物的研究只考虑单细胞水平上的遗传和/或细胞机制。然而，药物渗透是一个非常重要的附加机制，需要更复杂的细胞环境来研究。在2011 -12财年，我们与V. Courtney Broaddus（加州大学旧金山分校）和Shuichi Takayama（密歇根大学）合作，建立了体外肿瘤球体来研究单克隆抗体治疗。除了为筛选更有效的抗肿瘤抗体提供创新平台外，这些肿瘤球体对于识别潜在的治疗靶点可能是非常宝贵的。在2012财年，我们使用微阵列分析比较了3D球体和传统2D单层的基因表达谱，并鉴定了100多个间皮瘤3D生物结构特异性基因。其中一些基因可能具有作为治疗靶点和诊断性生物标志物的潜力。在2011 -12财年，这项工作在PloS ONE上发表了两篇研究论文，并在诸如蛋白质治疗论坛和PEGS抗体癌症治疗研讨会等国际研讨会上发表。球体研究部分得到了NCI主任的校内创新奖（首席研究员奖）的支持。

The Antibody Therapy Section aims to develop novel antibody therapies for liver cancer as well as other cancers. Project 1: Targeting glypican-3 in hepatocellular carcinoma Liver cancer is the fifth most common cancer and the third leading cause of cancer mortality in the world. Hepatocellular carcinoma (HCC) accounts for approximately 75% of liver cancer cases. Cholangiocarcinoma (CCA) is the second most common primary liver tumor. There is an urgent need for new treatments that can be successfully applied to a large population of liver cancer patients. With a primary interest in investigating glypican-3 (GPC3), this target holds potential for liver cancer therapy, given its high protein expression in HCC. In FY11-12, we generated the YP7 monoclonal antibody (mAb) with high affinity to GPC3 by hybridoma technology. In FY12, we conducted animal testing and showed that YP7 exhibited significant HCC xenograft tumor growth inhibition in mice. This work was published in the journal mAbs and featured on its cover. Ongoing studies are focused on exploring the mechanisms underlying the role of GPC3 in HCC pathogenesis and on the development of human antibodies targeting GPC3 for liver cancer therapy. The NCI has filed patent applications based on our GPC3 monoclonal antibodies. We hope to find industrial partners to collaborate with us in the development of novel GPC3-targeted antibody therapy to treat liver cancer. In FY12, the GPC3 project yielded three publications in the journals mAbs, BioDrugs and Cancer Reports. We presented our work at international symposia such as 2nd Annual PEGS Antibodies for Cancer Therapy Symposium, Protein Discovery & Therapeutics, and Antibodies for the 21st. Project 2: Targeting mesothelin in liver cancer, mesothelioma and ovarian cancer Mesothelin is expressed at high levels in mesothelioma, cholangiocarcinoma, ovarian as well as pancreatic and lung cancers. In FY10, we analyzed protein expression of mesothelin in liver cancer tissues and hypothesized that mesothelin is a potential therapeutic target in cholangiocarcinoma (CCA). In collaboration with Ira Pastan at the NCI, we applied our expertise in phage display technology to identify HN1, a human mAb specific for mesothelin. The HN1 mAb binds cell surface-associated mesothelin with high affinity and kills cancer cells with excellent antibody-dependent cell mediated cytotoxicity (ADCC) and is promising for the treatment of mesothelin-expressing cancers. In FY11, we published the HN1 work in the International Journal of Cancer. Our mesothelin project was supported in part by a Mesothelioma Applied Research Foundation research grant and the Ovarian Cancer Research Fund Individual Investigator Award to Mitchell Ho. In FY12, in collaboration with Ira Pastan and Dimiter Dimitrov (NCI's Frederick National Lab), we isolated novel single-domain human antibodies against mesothelin by phage display technology. These human antibodies may have novel anti-tumor activities against mesothelin-positive tumor cells. The NCI has filed patent applications on our mesothelin antibodies for cancer therapy. NCI also provides the LMB-H226-GL mesothelioma model developed in our lab as a Research Tool to the scientific community. Project 3: Establish in vitro tumor spheroids to investigate antibody therapy. Most studies of anticancer drugs consider only genetic and/or cellular mechanisms at the level of the single cell. However, drug penetration is a highly important additional mechanism and requires a more complex cellular environment for study. In FY11-12, in collaboration with V. Courtney Broaddus (University of California San Francisco) and Shuichi Takayama (University of Michigan), we established in vitro tumor spheroids to study monoclonal antibody therapy. These tumor spheroids may prove invaluable for identifying potential therapeutic targets in addition to providing an innovative platform for screening more effective anti-tumor antibodies. In FY12, we compared the gene expression profiles of 3D spheroids and conventional 2D monolayers using microarray analysis and identified over 100 genes specific to the 3D biological structure of mesothelioma. Some of these genes may have potential as therapeutic targets and diagnostic biomarkers. In FY11-12, this work yielded two research articles in PloS ONE and presented at international symposia such as the Protein Therapeutics Forum and PEGS Antibodies for Cancer Therapy Symposium. The spheroid work was supported in part by the NCI Director's Intramural Innovation Award (Principal Investigator Award) to Mitchell Ho.