P21 transcriptional inhibitors as proapoptotic compounds

描述（由申请人提供）： 放疗和化疗都是癌症治疗的重要方式。它 有人建议这些抗癌疗法通过消除肿瘤细胞 诱导程序性细胞死亡（细胞凋亡）。细胞周期蛋白依赖性激酶 抑制剂 p21 (Wafl/Cipl) 在转录水平上被诱导 参与癌症发展的信号通路，以及 各种抗癌治疗。越来越多的证据表明 p21 是 细胞凋亡的一般抑制剂。我们假设 p21 的抑制 肿瘤细胞中的转录将增强它们对辐射的反应 化疗，因为 p21 的转录诱导通常会导致肿瘤 对这些治疗有抵抗力。我们提出了一项识别化学物质的策略 p21 启动子抑制剂，我们计划测试有效的化学抑制剂 p21 转录与肿瘤中的放疗和化疗药物一起 不同来源和异种移植肿瘤的细胞系，以评估其 通过 p53 依赖性和非依赖性细胞凋亡对细胞杀伤的影响。一个细胞 与人类 p21 启动子控制下的细菌 LacZ 基因一致， 阿霉素可通过 p53 依赖性机制高度诱导 将成立。该细胞系将用于识别化学物质 通过筛选单个化合物来抑制 p21 转录 可从 Chembridge 购买的化学 DlVERSet TM 库 公司。抑制 p21 启动子的化合物将在 含有 lacZ 报告基因的 ConA 细胞系 ap53响应启动子，以确保它们不会损害 p53 作为转录激活剂。最有效的抑制剂 p21 启动子的 p53 依赖性激活不影响 p53 依赖性 ConA 细胞中 LacZ 的激活将在体外和体内进行鉴定和测试 体内。这些化合物将代表 p21 启动子的阻遏物，但不是 p53 抑制剂。该研究的具体目的是确定化学物质 p21转录抑制剂并结合测试它们 癌细胞系和异种移植肿瘤中的化疗药物。我们期望 这些化合物将使肿瘤细胞对抗癌治疗敏感， 验证 p21 表达作为治疗靶点。这项研究可能会改善 通过识别新化合物来治疗癌症 将提高促进细胞死亡的抗癌药物的效率 癌症治疗。

DESCRIPTION (provided by applicant): Both radiation and chemotherapy are important modes of cancer treatment. It has been suggested that these anticancer treatments eliminate tumor cells by inducing programmed cell death (apoptosis). The cyclin-dependent kinase inhibitor p21 (Wafl/Cipl) is induced at the transcriptional level both by signaling pathways that participate in the development of cancer, and by a variety of anticancer treatments. There is a mounting evidence that p21 is a general inhibitor of apoptosis. We hypothesize that suppression of p21 transcription in tumor cells will enhance their response to radiation and chemotherapy because transcriptional induction of p21 usually makes tumors resistant to these treatments. We propose a strategy to identify chemical inhibitors of p21 promoter and we plan to test potent chemical inhibitors of p21 transcription together with radiation and chemotherapeutic drugs in tumor cell lines of different origin and in xenograft tumors to evaluate their effect on cell killing via p53-dependent and -independent apoptosis. A cell line with the bacterial LacZ gene under control of the human p21 promoter, which will be highly inducible by adriamycin via a p53-dependent mechanism will be established. This cell line will be used for identifying chemical inhibitors of p21 transcription by screening of individual compounds of a chemical DlVERSet(TM) library that is commerically available from Chembridge Corporation. Compounds that repress the p21 promoter will be rescreened in a ConA cell line containing the lacZ reporter gene under the control of ap53-responsive promoter to ensure that they do not compromise the ability of p53 to act as a transcriptional activator. The most potent inhibitors of p53-dependent activation of the p21 promoter that do not affect p53-dependent activation of LacZ in ConA cells will be identified and tested in vitro and in vivo. These compounds will represent repressors of the p21 promoter, but not inhibitors of p53. The specific aims of the study are to identify chemical inhibitors of p21 transcription and to test them in combination with chemotherapeutic drugs in cancer cell lines and xenograft tumors. We expect that such compounds will sensitize tumor cells to anti-cancer therapy, validating p21 expression as a therapeutic target. This study may improve treatment of cancer by leading to the identification of new compounds that will increase the efficiency of cell death promoting anticancer drugs for cancer treatment.