养阴解毒法对吉非替尼耐药PC9肺腺癌miRNA-21的作用机制研究

In 21st century, targeted therapy is the research direction of oncology, which possesses high efficiency in treating lung cancer of EGFR gene sensitive mutation. However, drug resistance has become the critical limit to further improve curative effect of targeted therapy in lung cancer, thus making the study of reversing targeted drug resistance the key and difficult point in lung cancer research. The project takes “strengthening vital Qi to treat cancer” theory of Jiaxiang Liu as guidance, starts from "syndrome differentiation" - the core of the diagnosis and treatment of TCM and studies the law of TCM syndrome after targeted therapy for lung cancer, to put forward the hypothesis that using the method of “Nourish yin and detoxification” to delay drug resistance of lung cancer. In recent years, miRNA has become the new target spot for lung cancer targeted therapy drug resistance. On one hand, the project uses miRNA transfection technique to interpret the mechanism of regulating effect of miRNA-21 in the drug resistance of gefitinib. On the other hand, by using the model of tumor transplanted into nude mice, comparing the effects of “nourishoy yin and detoxification” and “waxiny qi ,nourishoy yin and detoxification” in differentially expressing miRNA of gefitinib-resistant lung adenocarcinoma and its sensitive PC9, studying the effect on the activity of PI3K/Akt signal pathway of miR - 21 controling target gene PTEN and PDCD4, to clarify the mechanism of TCM slowing down gefitinib’s drug resistance, to provide scientific experimental basis for the application of the theory of strengthening vital Qi to treat cancer in the targeted therapy and fill the blank of TCM syndrome differentiation research in the field.

靶向治疗是21世纪肿瘤学研究的方向，对于EGFR基因敏感突变的肺癌靶向治疗有效率高，但是耐药已成为限制肺癌靶向治疗进一步提高疗效的关键，逆转靶向耐药的研究成为肺癌研究的重点和难点。本课题以刘嘉湘“扶正治癌”理论为指导，从中医诊治疾病的核心“辨证”着手，通过对肺癌靶向治疗后中医证候规律研究，提出养阴解毒法延缓肺癌耐药的假说。近年来，miRNA成为肺癌靶向治疗耐药的新靶点，本课题一方面采用miRNA转染技术，阐释miRNA-21在吉非替尼耐药中的调控作用机制，同时采用裸鼠移植瘤模型，通过比较养阴解毒法和益气养阴解毒法对吉非替尼耐药肺腺癌及其敏感PC9差异表达miRNA的影响，研究miR-21调控靶基因PTEN和PDCD4对PI3K/Akt信号通路活性的影响，阐明中医辨证延缓吉非替尼耐药的作用机制，为中医“扶正治癌”理论在靶向治疗中的应用提供科学的实验依据，填补靶向治疗领域中医辨证研究空白。

靶向治疗是21世纪肿瘤学研究的方向，表皮生长因子受体酪氨酸激酶抑制EGFR-TKI已成为晚期非小细胞肺癌EGFR基因敏感突变的一线治疗方案，临床治疗有效率高，副作用小，应用广泛。但是EGFR-TKI耐药已成为限制肺癌靶向治疗进一步提高疗效的关键，已经有多项大型随机对照研究EGFR-TKI在EGFR敏感突变晚期NSCLC患者的中位生存期仅有8-10月左右，因此研究逆转靶向耐药的研究成为肺癌研究的重点和难点。中医扶正法治疗肺癌具有多层次、多靶点综合调节的作用特点，而EGFR-TKI治疗肺癌的特点是针对性强，对局部病灶的控制具有较好疗效，最终会出现耐药而失效；中医扶正治癌与靶向治疗优势互补，弥补中医药在病灶控制方面的不足，符合WHO将肿瘤作为慢性病治疗的概念，是肿瘤治疗模式和理念的革新。本课题以国医大师刘嘉湘“扶正治癌”理论为指导，从中医诊治疾病的核心“辨证”着手，通过对肺癌靶向治疗后中医证候规律研究，提出养阴解毒法延缓肺癌耐药的假说。选择益气养阴解毒的代表方剂金复康口服液和自拟方养阴解毒方，采用人肺腺癌PC9及其耐药细胞株PC9/R，以体内外结合的方法研究中医药延缓吉非替尼耐药的作用和机制，结果显示养阴解毒法体内外均可抑制吉非替尼耐药细胞株PC9/R的增殖，并可诱导其凋亡，与吉非替尼联合应用有增效作用，其作用机制可能与通过降低miRNA-21的表达从而增强PTEN、PDCD4的表达以抑制PI3K/AKT通路活化的信号，从而延缓吉非替尼耐药。为中医“扶正治癌”理论在靶向治疗中的应用提供科学的实验依据，填补靶向治疗领域中医辨证研究空白。但是中药复方成分复杂，作用靶点多，对逆转吉非替尼耐药的机制有待进一步深入阐释和研究。