Modulation of the S100A9/CD33 Pathway by the Flavonoids ICA and ICT on the Tumor

描述（由申请人提供）：类黄酮伊卡和ICT对肿瘤微环境的S100 A9/CD 33通路的调节背景：骨髓来源的抑制性细胞是最近衍生的肿瘤微环境的组分，其已被确定在癌症的维持和进展中具有关键作用。这些细胞有助于与肿瘤进展相关的炎症如MRP 8/9的上调。黄酮类化合物是一组多酚化合物，通常存在于具有许多生物学能力的植物中，这些生物学能力可以证明在对抗疾病的斗争中有用，包括抗炎，抗氧化以及最近的抗肿瘤特性。从淫羊藿中提取的活性成分淫羊藿苷（伊卡）及其衍生物3，5，7-三羟基-4 ′-甲氧基-8-（3-羟基-3-甲基丁基）黄酮（ICT）具有很强的免疫调节和抗肿瘤作用。假设和目的：我们最近已经表明，这两种化合物都具有有效的调节作用，涉及来自肿瘤微环境的MDSC和MRP 8/14的下调以及STAT 3、NF-kB和MAPK通路组分的失活、体外肿瘤细胞的细胞毒性和小鼠癌症模型中肿瘤负荷的降低。虽然在认识这些化合物对癌症的治疗潜力方面取得了长足的进步，但对其作用机制知之甚少。特别是，我们假设对MDSC的影响与PDE 5的抑制有关，就像在合成药物如伟哥中看到的那样。我们还假设这些化合物对炎症途径的作用是通过磷酸酶的激活和可能的上调介导的，特别是PP 2A，如先前所建议的。这种特殊的作用可能与这些化合物对癌细胞的直接细胞毒性作用有关。在体内，这些药物也可能对肿瘤微环境的结构产生直接影响，导致其不稳定和抑制肿瘤生长。因此，通过伊卡和ICT对MDSC和与癌症相关的炎症标志物的调节所涉及的机制的研究将提供使这些化合物更接近临床用于未来治疗应用的见解。具体目标：目标1：了解PDE 5抑制对伊卡/ICT作用的作用。目的2：探讨磷酸酶在伊卡和ICT致炎介质失活中的作用。目的3：研究伊卡/ICT对肿瘤微环境的调控机制。研究设计：对于目标1，我们将首先继续进行计算机模拟，以证明ICT与PDE 5结合的特异性。我们将继续我们的评估，这种结合与机制在体外研究，并确定是否机制是类似的， 其他PDE 5抑制剂如西地那非，我们的对照。我们还将确定PDE 5抑制的一些作用是否也影响肿瘤细胞。对于目标2，我们将确定磷酸酶对关键促炎通路NF-κ B、Akt、ERK、p38和Stat 3失活的作用。PP 2A和SHP 1是唯一的磷酸酶吗？有没有一种特定类型的磷酸酶被伊卡和ICT激活。对于目标3，我们将进行体内研究，以了解这些途径的作用以及它们中的每一个在伊卡和ICT的调节作用中所起的重要作用。

DESCRIPTION (provided by applicant): Modulation of the S100A9/CD33 pathway by the flavonoids ICA and ICT on the tumor microenvironment Background: Myeloid-derived suppressive cells are a recently derived component of the tumor microenvironment that has been determined to have a pivotal role in the maintenance and progression of cancer. These cells contribute to the upregulation of inflammatory correlated with tumor progression such as MRP8/9. Flavonoids are a group of polyphenolic compounds, commonly found on plants with many biological abilities that could prove useful in the battle against disease including anti-inflammatory, antioxidant and, more recently, anti-tumorigenic properties. Those obtained from Herba Epimedii, specifically its active compound icariin (ICA) and a derivative named 3, 5, 7-Trihydroxy-4'-methoxy-8-(3-hydroxy-3- methylbutyl)-flavone (ICT), have been shown to have strong immunomodulatory as well as anti-tumorigenic effects. Hypothesis and objective: We have recently shown that both of these compounds have potent modulatory effects that involve the downregulation of MDSC and MRP8/14 from the tumor microenvironment as well as the deactivation of STAT3, NF-kB and MAPK pathway components, cytotoxicity of tumor cells in vitro and the reduction of tumor burden in a mice model of cancer. While strides have been made in recognizing the role of these compounds on their therapeutic potential against cancer, their mechanisms of action is poorly understood. In particular we hypothesize that the effect on MDSC is linked to the inhibition of PDE5 just as seen with synthetic drugs like Viagra. We also hypothesize that the effect of these compounds on inflammatory pathways is mediated by the activation and perhaps upregulation of phosphatases, in particular PP2A as has been suggested previously. This particular effect might be linked to the direct cytotoxic effect of thes compounds on cancer cells. It is also possible that in vivo these drugs could have a direct impact on the architecture of the tumor microenvironment that lead to its destabilization and the inhibition of tumor growth. Therefore the study of the mechanisms involved in the modulation of MDSC and inflammatory markers linked to cancer by ICA and ICT would provide the insight to bring these compounds one step closer to the clinic for future therapeutical applications. Specific aims: Aim1: To understand the role of PDE5 inhibition on ICA/ICT action. Aim 2: To investigate the role of phosphatases on the deactivation of pro-inflammatory mediators by ICA and ICT. Aim 3: To study the regulatory mechanisms of ICA/ICT on the in vivo tumor microenvironment. Study design: For aim 1, we will first continue in silico modeling that demonstrates the specificities of the binding of ICT with PDE5. We will continue our assessment of this binding with mechanistic in vitro studies and determine if the mechanism is similar to that of other PDE5 inhibitors like sildenafil, our control. We will also determine if some of the effect of PDE5 inhibition affect tumor cells as well. For aim 2, we will determine the role of phosphatases on the deactivation of key pro-inflammatory pathways NF-kB, Akt, ERK, p38, and Stat3. Are PP2A and SHP1 the only phosphatases? Is there a specific type of phosphatases that gets activated by ICA and ICT. For aim 3, we will do in vivo studies to understand the role of these pathways and the importance each one of them plays in the modulatory role of ICA and ICT.