TGF-β介导Wnt/β-catenin活化在骨肉瘤形成中的作用及重芪散防治机制研究

Osteosarcoma is common in adolescents，which is characterized by very high malignancy, complex etiology, unclear pathogenesis, very poor prognosis and lack of effective treatment.This project is based on the theory of traditional Chinese medicine:"Ulcer was caused by qi and blood coagulation because of the heat-toxicity"and takes clinical specimens, genetically modified cells and mice, xenografts models in mice as study objects. Technologies of cell and molecular biology, immunology and experimental oncology are used to study the critical role and molecular mechanism of crosstalk between TGF-βand Wnt/β-catenin signaling pathways in process of initiation, development and metastasis of osteosarcoma. At the same time, we will dissect ChongQi San formula on the effect of inhibition of protease activity and regulation of cell cycle, critical signaling pathway to induce cancer cell apoptosis at the molecular, cellular and organism levels and find out the main active ingredient of ChongQi San both in the process of anti-osteosarcoma and reversal the resistance of osteosarcoma cell to TRAIL in vitro and in vivo. We will explore which active ingredient serve as principal or adjuvant components in the formula and how they work. Dissection the mode of action of clinically effective formulae may be a good strategy in exploring the value and addressing the possible beneficial effects of ChongQi San formula with current biomedical approaches, which could provide the guiding rule for clinicians to treat osteosarcoma.

骨肉瘤好发于青少年，恶性度甚高，发病因素复杂，机制不明确，缺乏有效治疗药物，预后极差。 根据《医宗金鉴》"痈疽原是火毒生，经络阻塞气血凝"等中医理论，以临床标本、转基因细胞、转基因小鼠、移植瘤小鼠模型为研究对象，结合细胞和分子生物学、免疫学、实验肿瘤等技术研究TGF-β和Wnt/β-catenin信号通路相互作用在骨肉瘤发生、发展和转移过程中的重要作用和分子机制；同时从抑制蛋白酶活性、调控细胞周期、诱导癌细胞凋亡的关键信号通路为切入点，研究重芪散有效组分在体内外的抗骨肉瘤效应及其逆转骨肉瘤细胞对TRAIL耐药的作用和机制，揭示重芪散抗骨肉瘤的疗效及其君、臣、佐使配伍规律和分子机制，用现代生物医学方法客观评价重芪散的治疗优势和价值，为临床工作提供抗骨肉瘤新药和指导法则。

骨肉瘤是一种儿童和青少年最常见的高度恶性肿瘤，其五年生存率低，恶性度高，临床尚无特异性治疗。重楼皂苷（Polyphyllin I，PPI）是从重楼中提取的一种活性化合物。本项目进行PPI杀灭骨肉瘤的效应及分子机制，以及其协同TRAIL抗骨肉瘤作用及相关分子机制的研究。研究结果显示，PPI及其与TRAIL联合作用可明显抑制骨肉瘤细胞增殖，迁移和侵袭能力，诱导细胞周期阻滞和细胞凋亡。并且PPI可抑制骨肉瘤裸鼠移植瘤的生长，同时揭示了PPI可能是通过Wnt/β-catenin信号通路发挥其抗骨肉瘤作用。并且，我们第一次提出并证实PPI是一种新型的蛋白酶体抑制剂，在纯化的人蛋白酶体和骨肉瘤细胞的培养液中均表现出对蛋白酶体的糜蛋白酶样活性具有选择性抑制作用。但是重楼皂苷所属中药制剂“重芪散”的中药煎剂对骨肉瘤裸鼠移植瘤未见明显抑瘤作用，考虑可能为复方煎剂的提纯方式以及复方煎剂溶度的疗效表达，我们打算后期改变复方煎剂提纯方式并进一步增加“重芪散”中药煎剂的浓度深入研究复方的抗骨肉瘤作用。本研究客观评价了重楼皂苷（Polyphyllin I，PPI）防治骨肉瘤的疗效机制，为临床用药提供了一定的理论基础。