p21WAF1/CIP1去泛素化介导复方浙贝颗粒逆转大肠癌化疗耐药的机制研究

Compound Zhe Bei granule can reverse the chemoresistance of colorectal carcinoma cell lines by up-regulating p21WAF1/CIP1 protein, a certain kind of cell cycle inhibitors, in our previous studies. In addition, the deubiquitination of p21WAF1/CIP1 contributes to the reversion of therapeutic resistance in colorectal colorectal carcinoma cell lines. Therefore，our objective is to evalutate the restoration effects of compound Zhe Bei granule to chemoresistance in colorectal cancers, and to understand the molecular mechanism of colorecatal cancer chemoresistance for future anticancer therapy targets discovery. We plan to induce two kinds of colorectal colorectal carcinoma cellular models by genetic engineering techniques in this project, one is called deubiquitination of p21WAF1/CIP1 colorectal carcinoma cellular model which is regarded as a reversal chemoresistant model. The other is p21WAF1/CIP gene silence colorectal cellular model which is regarded as a primary chemoresistant model. To broaden our researches, the reversal effects of compound Zhe Bei granule to chemoresistance in colorectal cancers will be evaluated by using the nu/nu mouse xenograft models. We will study the effects of compound Zhe Bei granule in targeting the deubiquitination of p21WAF1/CIP1 in these two p21WAF1/CIP1 expression models mentioned above, as well as the effects of compound Zhe Bei granule reversing chemoresistance in colorectal cancer will be evalutated in vivo and in vitro models. Furthermore, we will study the effects of compound Zhe Bei granule in the p53/p21 pathway. The outcome may guide future clinical applications and references of compound Zhe Bei granule for decreasing the therapy expenses of chemoresistant colorectal cancer patients based on the precise knowledge of molecular therapy targets. Our long-term goal is to establish this innovative anticancer strategy as a feasible method for improving the efficacy of chemotheraphy in Jiangxi province.

之前研究中发现，复方浙贝颗粒能通过上调细胞周期蛋白激酶抑制剂p21WAF1/CIP1表达而逆转大肠癌细胞化疗耐药，并且这种逆转化疗耐药作用与p21WAF1/CIP1去泛素化有关。为了进一步明确该复方逆转大肠癌化疗耐药的分子机制及作用靶点，本研究拟用基因工程技术制备p21WAF1/CIP去泛素化（逆转化疗耐药模型）和p21WAF1/CIP1基因沉默（原发性化疗耐药模型）这两种大肠癌细胞模型，通过体外细胞实验和裸鼠移植瘤模型实验两种研究途径，观察在p21WAF1/CIP1去泛素化和p21WAF1/CIP1缺失两种条件下，复方浙贝颗粒逆转大肠癌化疗耐药的效应机制，并观察复方浙贝颗粒对p21WAF1/CIP1去泛素化作用及对p53/p21信号通路的影响，以期明确p21WAF1/CIP1去泛素化介导复方浙贝颗粒逆转大肠癌化疗耐药的作用机制，为提高江西省大肠癌化疗耐药患者的疗效，降低治疗费用提供参考。

《p21WAF1/CIP1去泛素化介导复方浙贝颗粒逆转大肠癌化疗耐药的机制研究》由细胞实验，动物实验和临床病理研究三部分构成。在细胞实验中，首次发现复方浙贝颗粒（CZBG）及其活性成份对人结肠癌HCT-116细胞的作用机制为：通过调控MDM2泛素化而活化P21蛋白，由活化的p21/p53通路介导其抗肿瘤和化疗增敏作用；并发现该药物活性成份可激活PI3K/Akt/AMPK 信号通路，诱导结肠癌细胞自噬式凋亡。在移植性裸鼠结肠癌动物模型中，发现CZBG活性成份腹腔注射（3mg/kg）抑瘤率为：58.44%，并可明显诱导瘤块细胞凋亡。在临床病理中，发现结肠癌P21蛋白的表达水平和中医痰证正相关,并与结肠癌化疗敏感性相关。结合流式细胞术、免疫组化、基因芯片和代谢组学分析作用机制证实，CZBG及其活性成份是通过调控肿瘤细胞P21蛋白泛素化、诱导自噬式凋亡、调控能量代谢而发挥直接和间接抗结肠癌效应。