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，我们将集中在维生素D的生理形式，1，25-二羟基维生素D3（1，25 D和类似物统称为“deltanoids”）的类似物的鉴定，这是最有效的，当与鼠尾草酸组合施用到白血病细胞。我们将研究基因表达的改变，以及其他可用作对这种治疗反应的生物标志物的细胞变化。 从患者新鲜获得的离体AML细胞和已建立培养物中的细胞将用于研究细胞分化、分化抗性、细胞周期停滞和存在治疗毒性剂时的存活机制。 大量先前的观察结果提供了基本原理，即三角洲类化合物诱导调节单核细胞分化的基因表达，但也可以导致分化抗性（特异性目标1）、分化相关的细胞周期停滞（特异性目标2）和依赖于microRNA 32和连接支架蛋白hKSR 2与NFkB复合物的信号传导途径的细胞存活变化（特异性目标3）。将特别关注已经批准用于人类施用的Deltanoids，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，包括向培养的细胞中加入药理学试剂、反义寡核苷酸、siRNA、分子诱饵和转染的质粒构建体，以研究这些操作的分子后果，这些后果将通过免疫印迹、定量RT-PCR、免疫沉淀和其他分子技术来确定。将通过测定细胞表面和分子标志物以及通过各种酶的活性和表达来监测分化细胞。 在基础研究中获得的信息将用于指导Deltanoid及其与分化增强剂鼠尾草酸的组合的临床试验的开发，而白血病细胞的体外转化研究将用于鉴定对Deltanoid的反应性的生物标志物和髓性白血病亚组的识别，这将是最适合启动计划的临床试验的。

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.