Ceramides for Breast Cancer Treatment

项目摘要/摘要 许多研究表明鞘磷脂信号通路与癌症之间存在相关性。 致病机制以及耐药性。神经鞘磷脂途径的中心分子神经酰胺也参与其中。 在包括乳腺癌在内的许多人类癌症中诱导细胞凋亡、衰老和生长停滞。 最近的研究表明，某些神经酰胺类似物具有优先杀伤的能力 和/或抑制葡萄糖神经酰胺合成酶(GCS)活性，这与 癌症多药耐药。该项目的主要假设是神经酰胺类似物可以被开发出来 作为治疗化疗耐药和侵袭性转移性乳腺癌的新药物 影响临床癌症治疗理念。我们的第二个假设是自体荧光神经酰胺 类似物可用于确认已知的神经酰胺作用机制，确定潜在的新的神经酰胺作用机制 行动，并发现新的目标和互动。 为该项目提出了四个具体目标： 特定目标1-开发杀灭候选耐药癌细胞的高效选择性药物 用于临床治疗乳腺癌的多药耐药和转移； 特异性目标2--确定导致耐药细胞和转移细胞凋亡的机制因素 细胞，并研究耐药癌细胞的优先杀伤与 神经酰胺类似物对葡萄糖神经酰胺合成酶和神经酰胺酶的抑制作用； 具体目标3-使用一种新的实验工具，自体荧光小分子，来研究 神经酰胺在癌细胞中的分布和作用； 具体目标4--测定最有效的靶标神经酰胺类似物的体内效应(S)。 为了实现这一特定目标，将合成40-45个自发荧光神经酰胺类似物。 扩展的芳香族共轭体系。为实现具体目标2、一般抗癌活性筛查 将用于鉴定有效的和选择性的神经酰胺类似物。一系列的力学研究 强效神经酰胺类似物将被用来检查类似物是否诱导细胞凋亡，如果是， 通过哪条途径(S)。糖神经酰胺水平测定、GCS和P-gp水平测定、耐药逆转 试验和神经酰胺酶抑制试验将确定目标类似物对活性和 GCS、P-gp和神经酰胺酶的表达。实现特定目标3，通过荧光 将跟踪目标荧光神经酰胺类似物在处理细胞中的显微镜、分布和作用， 验证作用机制。最后，最有效的类似物将被用于动物研究，以实现 具体目标4. 该项目的长期目标是提高乳房的存活率和生活质量。 通过靶向神经酰胺信号通路治疗癌症患者。本科生，包括 研究培训计划的参与者将参与该项目的各个方面。

PROJECT SUMMARY/ABSTRACT Many studies have shown a correlation between the sphingolipid signaling pathway and cancer pathogenesis as well as drug-resistance. The central molecule in sphingolipid pathway, ceramide, is involved in the induction of apoptosis, senescence, and growth arrest in many human cancers including breast cancer. Recent studies have shown that certain ceramide analogs possess the capability of preferentially killing resistant cancer cells and/or inhibiting glucosylceramide synthase (GCS) activity, which is highly correlated to cancer multidrug-resistance. The main hypothesis of this project is that ceramide analogs can be developed as new therapeutic agents for the treatment of chemo-resistant and aggressive metastatic breast cancers influencing clinical cancer treatment concepts. Our Secondary hypothesis is that self-fluorescent ceramide analogs can be used to affirm known ceramide mechanisms of action, determine potential new mechanisms of action, and discover novel targets and interactions. Four specific aims are proposed for the Project: Specific Aim 1 - Development of highly potent selective agents for killing resistant cancer cells as candidates for clinical treatment of breast cancer multidrug-resistance and metastasis; Specific Aim 2 - Determination of the mechanistic factors leading to the apoptosis of resistant and metastatic cells, and investigating the relationship between preferential killing of resistant cancer cells and glucosylceramide synthase (GCS) and ceramidase inhibition by ceramide analogs; Specific Aim 3 - Using a novel experimental tool, self-fluorescent small molecules, for investigating the distribution and action of ceramides in cancer cells; and Specific Aim 4 - Determination of the in vivo effects of the most potent target ceramide analog(s). To achieve the Specific Aim 1, 40-45 self-fluorescent ceramide analogs will be synthesized with extended aromatic conjugated systems. To achieve the Specific Aim 2, general anticancer activity screenings will be performed to identify the effective and selective ceramide analogs. A series of mechanistic studies on the potent ceramide analogs will be performed to examine whether the analogs induce apoptosis, and if yes, through which pathway(s). A glucosylceramide level assay, GCS and P-gp level assays, resistance-reversal assays, and ceramidase inhibition assays will determine the effects of the target analogs on the activity and expression of GCS and P-gp and ceramidase. To achieve the Specific Aim 3, through fluorescence microscopy, distribution and actions of the target fluorescent ceramide analogs will be tracked in treated cells, validating the mechanisms of action. Finally, most potent analogs will be used in animal studies to achieve the Specific Aim 4. The long-term objective of this project is to improve the survival rate and quality of life of breast cancer patients by targeting the ceramide signaling pathway. Undergraduate research students, including participants in research training programs, will be involved in all aspects of the Project.