miR-1/14-3-3ξ调控IL-6自分泌进而抑制肿瘤干细胞样特性在咖啡酸抑制肝癌侵袭转移中的作用

The prevention and treatment of cancer by dietary factors have been received more and more attention. Hepatocellular carcinoma (HCC) is the most common cancer in our country; the invasion and metastasis of HCC is one of the key factors which affect the prognostic of HCC patients. So the anti-invasion/metastasis by dietary factors has become a new way in the prevention and treatment of HCC. Here, based on our previous studies and on the researches worldwide, we choose an important component of the diet, caffeic acid (CaA), and suggest a new mechanism underlying the anti-invasion/metastasis. That is CaA epigenetic targets and decreases the expression of 14-3-3ξ. As an important manager, which regulates some of the key up-stream transcriptional factors of IL-6, 14-3-3ξ elevates IL-6 effectively. CaA blocks the attenuation of IL-6 by 14-3-3ξ, which attenuates the cancer stem cells-like protein of HCC cells, and finally inhibits the invasion/metastasis of HCC. Our project will perform the work in the cell and animal models. Moreover, we will also indicate the significance of the serum miR-1, 14-3-3ξ and IL-6 in the invasion/metastasis potential, as well as therapeutic effect of HCC. So our project will elevate our knowledge underlying in the molecular mechanisms whereby CaA inhibits the tumor progression; Further, our project will also facilitate for searching the new HCC dietary intervention targets.

膳食因子对恶性肿瘤的防治作用已日益受到关注；中国是肝癌高发国家，侵袭转移是影响肝癌患者预后的最主要因素之一；因此应用膳食因子抑制侵袭转移对防治肝癌具有十分重要的意义。本课题根据前期积累，结合国内外报道，提出膳食中重要成分咖啡酸抑制肝癌侵袭转移分子机制假说如下：咖啡酸通过miR-1靶向抑制14-3-3ξ，作为重要的磷酸化调控蛋白，14-3-3ξ的失活有效的抑制了肝癌炎症微环境中的核心分子IL-6，继而下调肝癌细胞的肿瘤干细胞样特性，最终抑制肝癌侵袭转移。本项目拟从细胞和动物水平系统探讨我们提出的科学假说，并进一步阐明血清miR-1、14-3-3ξ和IL-6在肝癌侵袭转移性以及膳食干预效果评估中的意义。为深入研究咖啡酸抗肿瘤作用的分子机制、寻找肝癌的膳食干预靶标提供新思路。

膳食营养对恶性肿瘤的防/治作用已日益受到关注，肝癌是我国当前社会重大公共卫生问题之一，侵袭转移是造成肝癌患者死亡的重要原因。本项目从细胞、动物及人群水平系统探讨了我们提出的科学假说，初步阐明miR-1/14-3-3调控IL-6自分泌进而抑制CSCs特性在CaA抗肝癌侵袭转移中的作用及机制。主要研究结果和研究意义如下：.1. CaA显著抑制肝癌细胞自分泌IL-6；同时CaA处理组中CD133和EpCAM表达水平和SP细胞比例均显著下降。CaA显著下调肝癌细胞NF-κB、SMAD2、SMAD3和STAT-3磷酸化水平；miR-1表达水平显著上升，而14-3-3和IL-6表达/分泌水平均显著下降。在肝癌细胞中高表达14-3-3显著上调IL-6的表达和自分泌水平；相反，在肝癌细胞中敲除miR-1则显著抑制CaA处理所致CD133、EpCAM、IL-6和14-3-3表达水平降低；而在此基础上同时敲除14-3-3能够显著逆转上述现象；CaA抑制细胞CSCs特性和侵袭转移能力亦发生逆转。.2. CaA处理能够显著抑制巨噬细胞的炎症应答，在此过程中NF-κB、STAT-3、IL-6和TNF-α等分子发挥了重要作用；敲除14-3-3亦可通过干预上述分子，抑制巨噬细胞炎症应答；14-3-3在CaA抑制巨噬细胞炎症应答过程中发挥重要作用。.3. CaA处理在对裸鼠体重和肝重均无显著影响的情况下，可显著抑制肝癌细胞裸鼠皮下移植瘤的生长，下调移植瘤细胞中14-3-3、IL-6、EMT和CSCs特性指标的表达水平，上调miR-1表达水平。.4. 通过Kaplan-Meier曲线发现14-3-3表达水平与肝癌预后和索拉菲尼抵抗呈显著相关性，14-3-3过表达组肝癌人群预后显著差于14-3-3低表达肝癌人群（研究拓展）。.本研究为继续深入系统研究CaA及其衍生物抗肿瘤作用的分子机制、寻找肝癌的膳食干预靶标，及发现新的预后评价指标提供了新思路。