CANCER CHEMOTHERAPY AT TRANSCRIPTIONAL LEVEL

拟议研究的目的是研究癌症的化疗。 基因转录水平。我们之前已经表明， 鸡成髓细胞白血病细胞中DNA依赖的RNA聚合酶II 在数量和质量上都与正常鸡不同 骨髓细胞。我们还从鸡肉中分离出一种蛋白质因子 白血病细胞，它通过以下方式刺激体外RNA合成 RNA聚合酶II。我们建议进一步纯化RNA聚合酶及其 同质性的启动因素。白血病AS中纯化的酶 和正常细胞一样，我们将研究它们的性质， 功能、亚单位结构和重构及其分析 产物RNA。预计这将为 白血病特异性RNA聚合酶。纯化的RNA聚合酶起始剂 将对因子进行研究以确定其性质、生理功能 以及它刺激RNA合成的启动机制。 还将尝试确定其在其他正常和 恶性细胞(正常鸡成髓细胞、禽成髓细胞病病毒 非生产细胞系、人白血病细胞系和人母细胞瘤细胞系)。 这些研究将揭示该因子是否为该基因所特有。 癌细胞生长的表达，或者它是RNA普遍需要的 真核细胞的合成。我们建议继续研究 几种目前使用的和较新的实验性抗肿瘤药物 它们对肿瘤基因转录的抑制作用以及对 抑制作用的生化机制。此建议书中使用的代理 包括胞嘧啶阿拉伯糖苷、诺如脲化合物、阿霉素及其 衍生物(AD 32、AD 41和AD 142)、6-巯基嘌呤及其甲基化 衍生品。这项拟议研究的最终目标是确定 有可能阻止癌细胞的肿瘤表达 选择性抑制肿瘤细胞活性的转录水平 RNA聚合酶(或其调节因子)不影响正常 酵素。

The aim of the proposed research is to study the chemotherapy of cancer at the level of gene transcription. We have previously shown that DNA-dependent RNA polymerase II in chicken myeloblastosis leukemic cells is different both quantitatively and qualitatively from that in normal chicken bone marrow cells. We have also isolated a protein factor from the chicken leukemic cells, whch stimulates the initiation of in vitro RNA synthesis by RNA polymerase II. We propose to further purify the RNA polymerase and its initiation factor to homogeneity. The purified enzymes from leukemic as well as normal cells will be studied with regard to their properties, functions, subunit structures and reconstruction, and analysis of their product RNA. This is expected to provide further evidence for a leukemic-specific RNA polymerase. The purified RNA polymerase initiation factor will be studied to determine its properties, physiological functions and the mechanism by which it stimulates the initiation of RNA synthesis. Attempts will also be made to determine its activity in other normal and malignant cells (normal chicken meloblast cells, avian myeloblastosis viral non-producer cell line, human leukemic and human blyphoma cell lines). These studies will reveal whether the factor is specific for the gene expression of cancerous growth or it is universally required for the RNA synthesis of eukaryotic cells. We propose to continue our studies on several currently used and newer experimental antineoplastic agents for thier inhibitory effects on neoplastic gene transcription, as well as the biochemical mechanisms of the inhibition. The agents used in this proposal include cytosine arabinoside, notrosourea compounds, adriamaycin and its derivatives (AD 32, AD 41 and AD 142), 6-mercaptopurine and its methylated derivatives. The ultimate goal of the proposed research is to determine if it is possible to arrest neoplastic expression of cancer cells at transcriptional level by selectively inhibiting the activity of malignant RNA polymerase (or its regulatory factor) without affecting the normal enzyme.