Adenovirus Replication-Competent Anti-Cancer Vector

描述（由申请人提供）：我们已经开发了几种用于癌症基因治疗的肿瘤特异性和组织特异性可复制腺病毒（Ad）载体。一种名为KD 3的载体在E1 A基因中有突变，使得KD 3不能在“正常”细胞中复制并破坏“正常”细胞。然而，KD 3可以在癌细胞中复制，因为它们具有有利于KD 3复制的微环境。KD 3在裂解细胞和从细胞到细胞传播方面是有效的，因为它过表达一种名为ADP的蛋白质，这种蛋白质增强了细胞裂解。第二个载体名为GZ 3，与KD 3相同，但它具有野生型E1 A基因。GZ 3具有很强的细胞溶解性，但它不是肿瘤特异性的，并且不能以其目前的形式用于治疗癌症。在过去的一年里，我们继续努力开发治疗癌症的最佳载体。我们已经构建了新的载体，命名为KD 3-COL和GZ 3-COL，其中E4启动子被称为COL的结肠癌特异性启动子所取代。这些Ad载体在结肠癌细胞中复制，但不复制其他类型的细胞。我们还构建了KD 3-TERT和GZ 3-TERT载体，它们将E4启动子替换为端粒酶的TERT启动子。这些载体应该在端粒酶阳性的癌细胞中复制，而不是在正常细胞中复制。我们还构建了一种分泌诱导凋亡蛋白而不妨碍载体复制的KD 3。该载体应该通过两种机制破坏肿瘤，载体裂解复制和感染细胞周围未感染细胞的凋亡。希望这种分泌的蛋白能够诱导已经转移的肿瘤细胞凋亡。我们建议在细胞培养中表征KD 3-COL、GZ 3-COL、KD 3-TERT、GZ 3-TERT和凋亡诱导载体，主要目的是确定它们对癌细胞的特异性以及它们在这些细胞中复制和扩散的能力。还将评估它们在免疫缺陷裸鼠中破坏或抑制人癌细胞生长的能力。将检查这些肿瘤的生长、病理和支持载体复制的能力。将研究这些载体在小鼠中的毒性和分布。 建议的商业应用：癌症是美国第二大死亡原因。我们开发的腺病毒抗癌载体有望为许多不同类型的癌症提供有效的治疗，包括结肠癌和前列腺癌。 因此，市场潜力非常大。

DESCRIPTION (provided by applicant): We have developed several tumor-specific and tissue-specific replication-competent adenoviruses (Ad) vectors for cancer gene therapy. One vector, named KD3, has a mutation in the E1A gene such that KD3 cannot replicate in, and destroy, "normal" cells. However, KD3 can replicate in cancer cells because they have a microenvironment conducive to KD3 replication. KD3 is efficient in lysing cells and spreading from cell-to-cell, because it overexpresses a protein named ADP which enhances cell lysis. A second vector, named GZ3, is identical to KD3 except it has a wild-type E1A gene. GZ3 is very cytolytic, but it is not tumor-specific and could not be used in its present form to treat cancer. In the past year, we have continued in our attempt to develop optimal vectors to treat cancer. We have constructed new vectors, named KD3-COL and GZ3-COL, where the E4 promoter is replaced by a colon cancer-specific promoter named COL. These Ad vectors replicate in colon cancer cells but not other types of cells. We have also constructed vectors named KD3-TERT and GZ3-TERT, which have the E4 promoter replaced by the TERT promoter for telomerase. These vectors should replicate in telomerase-positive cancer cells but not in normal cells. We have also constructed a version of KD3 that secretes an apoptosis-inducing protein without precluding the replication of the vector. This vector should destroy tumors by two mechanisms, vector lytic replication and apoptosis of uninfected cells surrounding the infected cells. Hopefully, the secreted protein may be able to induce apoptosis in tumors that have metastasized. We propose to characterize KD3-COL, GZ3-COL, KD3-TERT, GZ3-TERT, and the apoptosis-inducing vector in cell culture, with the primary aim of ascertaining their specificity to cancer cells together with their ability to replicate and spread in these cells. They will also be evaluated for their ability to destroy or suppress the growth of human cancer cells in immunodeficient nude mice. These tumors will be examined with respect to their growth, pathology, and ability to support vector replication. The toxicity and distribution of these vectors in mice will be studied. PROPOSED COMMERCIAL APPLICATION: Cancer is the second leading cause of death in the USA. The adenovirus anti-cancer vectors that wwe have developed are expected to provide effective treatment of many different types of cancers, including colon and prostate. Accordingly, the market potential is extremely large.