Vitamin D Analogs as Adjuvants in Chemotherapy of Cancer

描述（由申请人提供）：本提案的总体目标是开发基于维生素d的治疗方案，以补充治疗，并设计预防人类急性髓性白血病（AML）的策略。具体来说，我们将专注于鉴定维生素D的生理形式的类似物，1,25-二羟基维生素D3 （1,25D和类似物统称为“类三角洲”），当与鼠尾草酸联合施用于白血病细胞时，它们是最有效的。我们将研究基因表达的改变，以及其他可以作为对这种治疗反应的生物标志物的细胞变化。离体AML细胞，从患者身上新鲜获得的细胞，以及已建立的培养细胞将用于研究细胞分化、分化抗性、细胞周期阻滞和治疗毒性药物存在下的生存机制。先前的许多观察提供了其基本原理，即三角洲类药物诱导调节单核细胞分化的基因表达，但也可能导致分化抵抗（Specific Aim 1），分化相关的细胞周期阻滞（Specific Aim 2），以及依赖于microRNA32和连接支架蛋白hKSR2与NFkB复合物的信号通路的细胞存活变化（Specific Aim 3）。将特别注意已经批准用于人用药的三角类药物，其分化活性被鼠尾草酸高度增强。该项目将通过多种方法完成，包括添加药物制剂、反义寡核苷酸、sirna、分子诱饵和转染质粒构建的培养细胞，以研究这些操作的分子后果，这些操作将通过免疫印迹、定量RT-PCR、免疫沉淀和其他分子技术来确定。分化细胞将通过测定细胞表面和分子标记，以及各种酶的活性和表达来监测。在基础研究中获得的信息将用于指导三角类药物的临床试验的发展，以及它们与分化增强剂鼠尾草酸的组合，而白血病细胞的体外转化研究将用于确定对三角类药物的反应性生物标志物和髓系白血病亚群的识别，这将是最适合开始计划的临床试验。

DESCRIPTION (provided by applicant): The overall goal of this proposal is to develop vitamin D-based therapeutic regimens to supplement the treatment, and design strategies for the prevention, of human acute myeloid leukemia (AML). Specifically, we will focus on the identification of analogs of the physiological form of vitamin D, 1,25- dihydroxyvitamin D3 (1,25D and analogs are collectively dubbed "deltanoids") which are the most effective when administered to leukemia cells in combination with Carnosic acid . We will study the alterations in gene expression, and other cellular changes that can be used as biomarkers of response to this treatment. AML cells ex vivo, freshly obtained from patients, and cells in established cultur will be used for studies of cell differentiation, resistance to differentiation, cell cycle arrest,and survival mechanisms in the presence of therapeutic toxic agents. The rationale is provided by numerous previous observations that deltanoids induce expression of genes which regulate monocytic differentiation but also can cause resistance to differentiation (Specific Aim 1), the differentiation-associated cell cycle arrest (Specific Aim 2), and cell survival changes dependent on microRNA32 and on signaling pathways that link the scaffold protein hKSR2 with NFkB complex(Specific Aim 3). Special attention will be given to deltanoids already approved for human administration the differentiation activity of which is highly enhanced by Carnosic acid. This project will be accomplished by a variety of approaches, including addition to cultured cells of pharmacological agents, antisense oligonucleotides, siRNAs, molecular decoys, and transfected plasmid constructs to study the molecular consequences of these manipulations, which will be determined by immunoblotting, quantitative RT-PCR, immunoprecipitation, and other molecular techniques. Differentiating cells will be monitored by determination of cell surface and molecular markers, as well as by the activity and the expression of various enzymes. The information obtained in basic studies will be utilized to guide development of Clinical Trials of deltanoids, and their combinations with the differentiation enhancer carnosic acid, while translational studies on leukemic cells ex vivo will serve to identify biomarkers of responsiveness to deltanoids and the recognition of subgroups of myeloid leukemias which will be the most suitable for the initiation of planned clinical trials. PUBLIC HEALTH RELEVANCE: Differentiation therapy, which depends on the activation of existing cellular programs rather than on toxic drugs to combat cancers and blood malignancies is already effective as the treatment of some of these diseases. We propose to develop it as treatment and prevention of blood malignancy known as acute myeloid leukemia which, although kills approximately 15,000 people in USA every year, is unlikely to receive attention for finding its cure from commercial sources. Therefore, acute myeloid leukemia can be considered an orphan disease and merits support from public sources for the development of novel therapy.