IMMUNOTHERAPY BY IN VIVO GENE TRANSFER INTO TUMORS

通过刺激免疫增强肿瘤消退的策略 对恶性细胞的反应在动物中显示出有限的功效， 人类研究，但代表了一个重要的潜在方法， 癌症的治疗。 我们开发了一种基因转移方法， 肿瘤细胞表面表达的免疫治疗 在肿瘤中使用直接体内基因转移的抗原。 我们有 以前的研究表明，将重组基因直接转移到肿瘤中， 在体内改变它们的免疫原性。 临床前研究表明， 引入编码高免疫原性蛋白质的基因， 同种异体I类主要组织相容性复合体（MHC）基因， 可移植小鼠肿瘤诱导特异性溶细胞T细胞抗 这种蛋白质也引起了对未经修饰的肿瘤的反应， 细胞，导致动物肿瘤消退或治愈。 人类研究 用外源MHC进行直接基因转移也已经进行， 支持这项赠款，并适用于黑色素瘤在两个独立的 人类I期临床研究完成于 密歇根医学中心的初步结果令人鼓舞。 在这 建议将外源组织相容性基因直接导入 结肠癌肝转移将被优化， 将分析患者中的表达和免疫应答， 了解导致成功应对的机制。 将评估同种异体MHC的表达，并将免疫学检测结果进行分析。 抗肿瘤反应的基础。 同种异体MHC的表达将是 评估，抗肿瘤反应的免疫学基础将被 表征了 这种分析也将用于开发系统 其允许免疫相关肿瘤的分子克隆- 相关抗原。 最后，我们将开发 对当前方案进行修改，以提高其在以下方面的疗效： 人类 为了理解和改进这种基因转移策略， 我们将：1）进行导管输送外源MHC基因，HLA- B7，进入结肠癌的转移性肝病变，利用改进的 载体和脂质体，2）分析基因表达，确定 肿瘤成功免疫应答和阐明的机制 排斥，和3）开发新的基因转移方法， 外源MHC和p21细胞周期蛋白的联合基因治疗， 依赖性激酶，其抑制细胞增殖并诱导终末 分化，这可能会促进进一步的变化， 肿瘤的免疫识别 这些研究扩展了目前 目前人类临床试验的技术，以提高疗效 基因转移方法治疗癌症，并将提供深入了解 恶性肿瘤免疫识别的分子基础。

Strategies to enhance tumor regression by stimulating the immune response to malignant cells have shown limited efficacy in animal and human studies, but represent an important potential approach to the treatment of cancer. We have developed a gene transfer approach to the immunotherapy of malignancy by expression of cell surface antigens in tumors using direct gene transfer in vivo. We had previously shown that direct transfer of recombinant genes to tumors in vivo alters their immunogenicity. Preclinical studies had shown that introduction of a gene encoding a highly immunogenic protein, from an allogeneic class I major histocompatibility complex (MHC) gene, in transplantable mouse tumors induced specific cytolytic T cells against this protein and also elicited a response against unmodified tumor cells, causing tumor regression or cure in animals. Human studies of direct gene transfer with foreign MHC have also been performed with the support of this grant and applied to melanoma in tow independent human phase I clinical studies completed at The University of Michigan medical Center with encouraging preliminary results. In this proposal, delivery of a foreign histocompatibility gene directly into colon carcinoma metastatic to liver will be optimized, and gene expression and immune response in patients will be analyzed to understand the mechanisms which lead to successful responses. Expression of allogeneic MHC will be assessed, and the immunologic basis of antitumor responses. Expression of allogeneic MHC will be assessed, and the immunologic basis of antitumor responses will be characterized. Such analyses will also be used to develop systems which allow molecular cloning of immunologically relevant tumor- associated antigens in the future. Finally, we will develop modifications of the current protocol which will improve its efficacy in humans. To understand and improve upon this gene transfer strategy, we will: 1) perform catheter delivery of a foreign MHC gene, HLA- B7, into metastatic liver lesions of colon cancer utilizing improved vectors and liposomes, 2) analyze gene expression, define correlates of successful immune responses and delineate mechanisms of tumor rejection, and 3) develop novel gene transfer approaches using combination gene therapy of foreign MHC and the p21 cyclin- dependent kinase, which arrests cell proliferation and induces terminal differentiation which may promote further changes which induce immune recognition of tumors. These studies expand on the present technology of current human clinical trials to improve the efficacy of gene transfer approaches to cancer and will provide insight into the molecular basis of immune recognition in malignancy.