虫草素抑制乳腺癌生长和转移的分子信号转导机制

It is well known that cordycepin, the main active ingredient in Cordyceps, has been used for treatment of malignancies in clinical therapy. However, its molecular mechanism is not clear yet. Breast cancer is the most commonly diagnosed cancer in women. The high frequency of pathogenesis and metastasis is correlated with aberrant activation of hedgehog pathway and the process of EMT. Our preliminary results showed that cordycepin down-regulates the expression of Hedgehog-Gli to induce apoptosis and inhibit migration in breast cancer cells, which further cause the up-regulation of E-Cadherin and down-regulation of N-Cadherin. Hereby, our current project proposes that cordycepin inhibits breast cancer cells proliferation and metastasis through regulating Hedgehog pathway. This project will in-depth investigate the effect of cordycepin in regulating Hedgehog pathway on breast cancer cell proliferation and metastasis through shRNA technology. In addition, we also evaluate the control efficiency of cordycepin against breast cancer and its biological effect in vivo. This study will provide mechanism for the treatment of breast cancer in novel therapeutic drugs, which will enhance the utility of bioactive ingredients of traditional Chinese.

虫草素是中药冬虫夏草的主要活性成份，已应用于临床抗肿瘤治疗，但其分子作用机制尚未明确。乳腺癌是女性最常见的恶性肿瘤，其高发病因和转移与Hedgehog通路的激活和EMT的发生有关。前期研究工作发现虫草素阻断Hedgehog-Gli的表达能诱导乳腺癌细胞凋亡和抑制细胞迁移，并上调E-Cadherin和下调N-Cadherin的表达。据此，本项目推测虫草素通过调控Hedgehog通路来抑制乳腺癌生长和转移的分子机制。本项目旨在深入分析虫草素调控Hedgehog通路对乳腺癌细胞生长和转移的影响作用；通过shRNA技术沉默Gli的表达，明确Hedgehog-Gli介导虫草素抑制乳腺癌生长和转移的信号转导机制；通过裸鼠移植瘤模型，阐明虫草素对乳腺癌的防治效果及其体内生物学效应。本研究结果将丰富中药资源活性成份药效药理学，为开发新型的抗乳腺癌药物提供新思路。

虫草素是中药蛹虫草的主要活性成分，具有抗肿瘤作用。乳腺癌是女性最常见的恶性肿瘤。评价虫草素抗乳腺癌的作用效果及阐明其分子作用机制是本项目的研究目标。因此，我们首先基于乳腺癌细胞，研究了虫草素对乳腺癌细胞生长与转移的影响作用，结果表明虫草素对人乳腺正常细胞低毒，但对人乳腺癌细胞具毒性作用、凋亡诱导作用和转移阻滞作用；接着基于裸鼠动物模型，研究了虫草素对乳腺癌移植瘤生长的影响作用，结果表明对照组的移植瘤体积是给药组的3.5倍（n=10,p<0.05）,对照组的实体瘤重是给药组的2.6倍（n=10,p<0.05），提示虫草素在体内显著性的抑制MDA-MB-231移植瘤的生长；进而基于RNA-seq技术，分析了虫草素对乳腺癌移植瘤生长抑制的体内分子效应，结果表明虫草素对移植瘤生长过程中多个生物学功能进程有显著的下调效应，并提示了抑制三阴性乳腺癌生长与转移的分子信号效应途径涉及Hedgehog通路、Hippo通路和EMT等；然后基于移植瘤组织，生物学功能验证了虫草素对乳腺癌移植瘤生长抑制的重要分子效应因子与Hedgehog信号通路，也表明转录组数据分析的可靠性与准确性；最后基于乳腺癌细胞，论证了虫草素通过调控Hedgehog信号通路及下游靶标抑制乳腺癌生长与转移的分子信号转导机制。综上数据，支撑了本项目的研究目标，提示虫草素作为中药资源低毒、高效的天然抗肿瘤药物具有深远的科学研究价值和潜在的开发应用前景。