Immunologic aspects of targeted therapy of erbB tumors

我们的总体假设是，序贯治疗癌蛋白失能单克隆抗体，然后IFN-γ导致 肿瘤细胞的表型变化从未用mAb本身实现。单克隆抗体诱导的表型变化 细胞或允许IFN-γ直接对肿瘤的意外作用。本提案的总体目标是 是为了更深入地了解erbB介导的肿瘤发生事件， 治疗和预防耐药肿瘤形成和扩散的出现。我们会委聘 MMTV NeuT-tdTomato转基因小鼠在番茄标记的乳腺中表达MMTV-neu蛋白 细胞，并像人类乳腺癌一样随机发生乳腺肿瘤。这些独特 转基因将受到针对p185癌蛋白的靶向治疗的影响， 与IFN-γ治疗同时进行。肿瘤的出现和扩散将被跟踪，细胞系从 进行进一步的生物化学研究。其他研究将采用抗p185抗体的配对给药 mAb和IFN-γ，以及具有修饰的效应结构域的抗erbB 2-scFv的新种类的用途， 我们通过基因连接了IFN-γ分子。MMTV NeuT-tdTomato转基因小鼠将成为 跟踪mAb单独或与IFN-γ组合对肿瘤进展和转移扩散的影响。 尽管用p185 neu的mAb治疗仍出现耐药肿瘤，将研究其表型和等位基因 肿瘤本身发生的变化，通过使用繁殖的细胞系，特别是我们拥有的基因， 被认为与恶性表型相关。我们对一种新的人源化单克隆抗体的研究 与人源化ZZ结构域（我们称之为ZED结构域）融合的mAb-IFN-γ重组蛋白将是 扩展到赫赛汀耐药乳腺癌。这种高度工程化的mAb种类同时使 p185 erbB 2/neu激酶;通过ZED结构域放大免疫球蛋白效应;最后， IFN-γ直接作用于人肿瘤细胞。我们将评估效应结构域修饰的靶向抗erbB 2 mAb是否也 影响由erbB 2/neu癌基因和其他体细胞突变如KiRas转化的细胞。这 构建体可以是用于人类疾病的治疗剂的原型。最后，我们还将评估， 与这种新种类的抗体一起使用的细胞毒性/遗传毒性信号（例如紫杉烷、紫杉醇）进一步 消除赫赛汀耐药肿瘤细胞。

Our overall hypothesis is that ordered therapy with oncoprotein disabling mAb followed by IFN-γ leads to phenotypic changes in tumor cells never achieved with mAb itself. MAb induced phenotypic changes sensitize cells or are permissive for unexpected actions of IFN-γ directly on the tumor. The overall goal of this proposal is to gain a deeper understanding of events of erbB mediated tumorigenesis and to develop more potent therapeutics to treat and prevent the emergence of resistant tumor formation and spread. We will employ MMTV NeuT-tdTomato transgenic mice created to express MMTV-neu proteins in Tomato tagged mammary cells and which develop breast tumors stochastically much like human breast cancer. These unique transgenics will be subjected to the effects of targeted therapy against the p185 oncoprotein followed by or concurrent with IFN-γ therapy. Tumor emergence and spread will be followed and cell lines developed from progressive tumors for further biochemical studies. Other studies will employ paired administration of anti-p185 mAb and IFN-γ, as well as use of a new species of anti-erbB2-scFv with a modified effector domain to which we have genetically attached the IFN-γ molecule. The MMTV NeuT-tdTomato transgenic mice will be hosts to follow the effects of mAb alone, or in combination with IFN-γ, on tumor progression and metastatic spread. Resistant tumors that arise despite treatment with mAb to p185neu will be studied for phenotypic and allelic changes that occur in the tumor itself, through the use of propogated cell lines, in particular genes we have considered to be relevant to the malignant phenotype. Our studies on a newly engineered mAb humanized mAb-IFN-γ recombinant protein fused with a humanized ZZ domain, (which we term the ZED domain) will be extended to Herceptin resistant breast cancers. This highly engineered mAb species simultaneously disables p185erbB2/neu kinases; amplifies immunoglobulin effects through the ZED domain; and, finally, delivers IFN-γ directly to human tumor cells. We will evaluate if effector domain modified targeting anti-erbB2 mAb also affects cells transformed by both the erbB2/neu oncogene and other somatic mutations such as KiRas. This construct may be a prototype of a therapeutic for human disease. Finally, we will also evaluate if cytotoxic/genotoxic signals (such as the taxane, docetaxol) used with this new species of antibody further eliminates Herceptin resistant tumor cells.