Stress-activated Protein Kinases and Chemotherapy

描述(由申请人提供)：抗癌剂与其主要靶点的相互作用仅代表药物作用机制的第一步。如果要在提高这些药物的有效性方面取得进展，了解随后诱导的凋亡信号机制是至关重要的。我们研究的总体目标是通过了解这些凋亡信号通路的性质和调节来改进癌症化疗。具体地说，我们感兴趣的是确定应激激活的c-jun氨基末端蛋白激酶(JNK)在抗有丝分裂抗癌药物，特别是长春花碱的作用机制中的作用。在特定的目标1中，我们将特异性地抑制c-Jun/AP-1的JNK信号转导，并检测AP-1抑制对长春花碱诱导的细胞凋亡和基因表达的影响，以确定AP-1的可能靶基因。《特殊目的2》将使用分子和细胞相结合的方法，测试相关AP-1靶基因作为长春花碱诱导细胞凋亡的中间产物。这一目标的完成将为已确定的候选基因的作用提供实验验证，并更好地理解长春花碱激活的JNK/AP-1的凋亡信号机制。特异性目标3将利用染色质免疫沉淀来证明c-jun被招募到相关AP-1靶基因的调控区域，并寻找可能与c-jun合作的新的调控伙伴。具体目标4将利用c-jun/-永生化成纤维细胞作为一个独特的模型系统，进一步探讨c-jun在长春花碱细胞反应中的作用。本研究将为JNKJC-JUN在长春花碱诱导细胞凋亡中的作用提供分子基础，并有助于我们对其作用机制及相关药物的基本了解。反过来，这项研究可能会提出新的方法来改变细胞死亡的阈值，使这些药物更有效，降低毒性，提高特异性。

DESCRIPTION (provided by applicant): The interaction of an anticancer agent with its primary target represents only the first step in the drug's mechanism of action. Knowledge of the apoptotic signaling mechanisms subsequently induced is of critical importance if advances are to be made in improving the effectiveness of these agents. The overall goal of our research is to improve cancer chemotherapy by understanding the nature and regulation of these apoptotic signaling pathways. Specifically, we are interested in defining the role of the stress-activated, c-Jun NH2-terminal protein kinase (JNK) in the mechanism of action of antimitotic anticancer drugs, particularly vinblastine. In Specific Aim 1 we will specifically inhibit JNK signaling to c-Jun/AP-1 and examine the effects of AP-1 inhibition on vinblastine-induced apoptosis and on gene expression in order to identify putative AP-1 target genes. Specific Aim 2 will test the relevant AP-1 target genes as intermediates in vinblastine-induced apoptosis, using a combination of molecular and cellular approaches. Completion of this aim will provide experimental verification of the role of the candidate genes identified, and a better understanding of the mechanisms of apoptotic signaling by vinblastine-activated JNK/AP-1. Specific Aim 3 will utilize chromatin immunoprecipitation to demonstrate recruitment of c-Jun to the regulatory regions of the relevant AP-1 target genes, and to identify novel regulatory partners that may cooperate with c-Jun. Specific Aim 4 will utilizec-jun-/- immortalized fibroblasts as a unique model system to further explore the role of c-Jun in the cellular response to vinblastine. This research will provide molecular insight into the role of JNKJc-Jun in vinblastine-induced apoptosis, and contribute to our basic understanding of the mechanism of action of this and related agents. In turn, this research may suggest novel approaches to alter the threshold for cell death to make these drugs more effective, lessening toxicity and improving specificity.