Role of E2F2 in eugenol-induced melanoma growth inhibit*

描述（由申请方提供）：本提案的长期目标是开发基于机制的联合方法，可预防原发性皮肤黑色素瘤进展为转移性疾病和/或导致转移性黑色素瘤消退。原发性皮肤黑色素瘤是可以治疗的。转移性形式是致命的，在患有IV期疾病的人中，10年生存率低于5%。我们已经确定丁香酚是黑色素瘤的有效抑制剂。我们实验室发表的数据也表明，丁香酚可预防B16异种移植瘤的转移。在这个提议中，我们想研究转录因子E2 F2的作用，我们发现它在其生长抑制活性中被丁香酚下调。我们假设E2 F2的过度表达在黑色素瘤细胞中解除了细胞周期控制，并且E2 F2的下调对于丁香酚诱导的细胞周期阻滞和凋亡诱导是必不可少的，而不依赖于DNA损伤信号通路。我们检验这一假设的具体目的是：确定E2 F2在黑色素瘤细胞的细胞周期进程失调中的作用及其参与丁香酚诱导的生长抑制作用。具体而言，我们将确定（i）E2 F2的抑制是否可以阻止黑素瘤细胞的连续循环，（ii）E2 F2是否是丁香酚诱导的S期阻滞和凋亡诱导中的关键参与者，以及（iii）丁香酚诱导的E2 F2下调的信号是否依赖于DNA损伤信号传导。该试点提案将定义E2 F2在黑色素瘤细胞进展过程中丁香酚诱导的生长抑制、凋亡诱导和细胞周期阻滞中的作用，并确定E2 F2对黑色素瘤细胞连续周期的影响。我们还将确定靶向E2 F2如何影响其他E2 F家族成员的功能，例如补偿E2 F2的缺失，以及确定丁香酚是否直接下调E2 F2或该作用是否通过DNA损伤介导。很明显，在癌症中多个途径被解除管制，使用靶向不同途径的各种药剂（化学和/或生物）的组合来攻击癌细胞是合乎逻辑的。在这项工作中，理解单个化合物的作用机制是至关重要的，以便可以开发合理的药物组合。该提案涉及癌症化学预防的这一核心，旨在减轻国家因治疗费用高昂和丧失生产能力而造成的负担。

DESCRIPTION (provided by applicant): The long-term objective of this proposal is to develop mechanism-based combination approaches that can either prevent the progression of primary cutaneous melanoma to metastatic disease and/or cause regression of metastatic melanoma. Primary cutaneous melanoma is treatable. The metastatic form is fatal with a 10-year survival rate of less than 5% in people who have stage IV disease. We have identified eugenol as a potent inhibitor of melanoma tumors. Published data from our laboratory also shows that eugenol prevents the metastasis of tumors in B16 xenografts. In this proposal we want to examine the role of the transcription factor E2F2 which we have found to be downregulated by eugenol in its growth inhibitory activity. We hypothesize that overexpression of E2F2 deregulates cell cycle control in melanoma cells and that downregulation of E2F2 is essential for eugenol-induced cell cycle block and apoptosis induction independent of DNA damage-signaling pathways. Our specific aim to test this hypothesis is: to identify the role of E2F2 in deregulating cell cycle progression in melanoma cells and its involvement in eugenol induced growth inhibitory effects. Specifically we will determine (i) if the inhibition of E2F2 can prevent the continuous cycling of melanoma cells (ii) if E2F2 is a key player in eugenol-induced S-phase block and apoptosis induction and (iii) if the signal for eugenol-induced E2F2 downregulation is dependent upon DNA damage signaling. This pilot proposal will define the role of E2F2 in eugenol-induced growth inhibition, apoptosis induction and cell cycle block during the progression of melanoma cells, and identify the influence of E2F2 on the continuous cycling of melanoma cells. We will also determine how targeting E2F2 can affect functions of other E2F family members such as compensating for the absence of E2F2 as well as identify whether eugenol directly downregulates E2F2 or whether the effect is mediated via DNA damage. It is clear that multiple pathways are deregulated in cancer, it is only logical that a combination of various agents (chemical and or biological) that target different pathways be used to attack cancer cells. In this effort it is of utmost importance that the mechanism(s) of action of individual compounds be understood so that a rational combination of agents may be developed. This proposal addresses this very core of cancer chemoprevention that aims to reduce the national burden of high cost of treatment and loss of productive life.