Vitamin D Analogs as Adjuvants in Chemotherapy

描述(由申请人提供)： 急性和慢性髓系白血病造成约15,000人死亡 美国每年都有。这些疾病经常折磨处于壮年的人，而且几乎不到一半的人通过目前的治疗方法实现长期缓解，大多数治疗方案既强烈又有毒，需要抗肿瘤多种化疗，在某些情况下，需要像异基因造血细胞移植这样的根治性治疗，及其伴随的风险。这项提议的总体目标是发展辨证治疗，以补充这一组疾病的治疗方案。我们将集中于鉴定最有效的生理形式维生素D的类似物，1，25-二羟基维生素D3(1，25D3)，在培养的白血病细胞中给予低浓度的1，25D3，以研究基因表达的变化和细胞生理学的其他变化。三角烷类化合物和1，25D3也将与目前用作食品防腐剂或添加剂的无毒物质或可能用于此类用途的无毒物质联合使用，以最大限度地提高三角烷类化合物的分化活性。已建立的白血病细胞系以及从患者新鲜获得的白血病细胞样本将用于细胞分化研究。通过对信号通路的研究，特别是对MAPK通路的研究，以及通过细胞周期蛋白依赖性蛋白激酶及其激活物和抑制物的表达对细胞周期的调控，将获得对分化控制的深入了解。这将通过添加药理学试剂、反义寡核苷酸、转录因子诱骗和转基因质粒构建物来研究这些操作的分子后果，这些操作将通过免疫印迹、Northern分析、RT-PCR、免疫共沉淀和其他标准技术来确定。分化细胞将通过测定表面标志物以及各种激酶的活性和它们的表达来监测。基础研究中获得的信息将被用来指导新一代Deltanid和Deltanid与共诱导剂组合的开发，而对白血病细胞的体外翻译研究将有助于确定最适合启动临床试验的髓系白血病亚群。

DESCRIPTION (provided by applicant): Acute and chronic myeloid leukemias are responsible for approximately 15,000 deaths in the USA every year. These diseases frequently afflict people in the prime of their lives, and substantially less than half of all achieve long-term remission with current therapies, Most treatment options are both intense and toxic, requiring anti-neoplastic poly-chemotherapy, and, in some cases, therapy as radical as allogeneic hematopoietic cell transplantation, with its attendant risks. The overall goal of this proposal is to develop differentiation therapy to supplement the treatment regimens for this group of diseases. We will focus on the identification of the most effective analogs (deltanoids) of the physiological form of vitamin D, 1,25- dihydroxyvitamin D3 (1,25D3) administered at low concentrations to leukemia cells in culture to study alterations in gene expression and other changes in cell physiology. The deltanoids and 1,25D3 will also be administered in combination with nontoxic substances currently used as food preservatives or additives, or with potential for such use, to maximize the differentiation activity of the deltanoids. Established lines of leukemia as well as samples of leukemic cells freshly obtained from patients will be used for studies of cell differentiation. Insight into differentiation control will be obtained by examination of signaling pathways with particular attention to MAPK pathways and into cell cycle regulation by the expression of cyclin-dependent kinases as well as their activators and inhibitors. This will be accomplished by adding pharmacological agents, antisense oligonucleotides, transcription factor decoys, and transfected plasmid constructs to study the molecular consequences of these manipulations, which will be determined by immunoblotting, Northern analysis, RT-PCR, coimmunoprecipitation, and other standard techniques. Differentiating cells will be monitored by determination of surface makers as well as the activity of various kinases as and as their expression. The information obtained in basic studies will be utilized to guide development of a new generation of deltanoids and deltanoid combinations with co-inducers, while translational studies on leukemic cells ex vivo will serve to identify subgroups of myeloid leukemias most suitable for the initiation of clinical trials.