肠胃清方对人结肠癌HCT116/L-OHP裸鼠皮下移植瘤miR-30a/Beclin1通路的影响

Effect of Changweiqing on miR-30a/Beclin1 pathway in subcutaneous xenografts of human colon cell line HCT116/L-OHP in nude mice

目的本课题旨在分子生物学技术和中医基础理论指导下,从miRNAs与自噬相关联的角度,讨论miR-30a与自噬基因Beclin1在结肠癌化疗耐药中的相关性,并探讨肠胃清对miR-30a介导自噬的调控作用及逆转结肠癌耐药的分子机制.方法建立人结肠癌耐奥沙利铂(L-OHP)细胞株HCT116/L-OHP裸鼠皮下移植瘤模型,随机分为空白组、L-OHP组、肠胃清方组、肠胃清方低剂量+L-OHP组、肠胃清方高剂量+L-OHP组.治疗结束后采用RT-PCR、免疫组织化学、Tunnel等研究肠胃清对瘤体组织中miR-30a、Beclin1、LC3的表达及细胞凋亡的影响.结果奥沙利铂组可见Beclin1、LC3的上调,miR-30a的下调,细胞凋亡的减少.而肠胃清联用奥沙利铂组可见Beclin1、LC3的下调,miR-30a的上调,细胞凋亡的增加(P<0.05或P<0.01).结论奥沙利铂诱导保护性自噬导致细胞凋亡减少可能是其耐药的机制.肠胃清可通过调控miR-30a/Beclin1通路而抑制自噬逆转结肠癌耐药.

AIM To evaluate the correlation of miR-30a and autophagy gene Beclinl with chemoresistance and to explore the possible mechanism for Changweiqing to reverse drug resistance in colon cancer therapy. METHODS A xenograft tumor model of oxaliplatin-resistant human colon cancer cell line HCT116/L-OHP was established in nude mice, and the mice were randomly divided into a control group, an L-OHP （oxaliplatin） group, a Changweiqing group, a low-dose Changweiqing ＋ L-OHP group, and a high-dose Changweiqing ＋ L-OHP group. The expression of miR-30a, Beclinl, and LC3 was evaluated by RT-PCR and immunohistochemistry, and cell apoptosis was evaluated by TUNEL assay. RESULTS The up-regulation of Beclinl and LC3 expression, down-regulation of miR-30a expression, and decrease of apoptosis were observed in the L-OHP group. However,the down-regulation of Beclinl and LC3 expression, up-regulation of miR-30a expression, and increase of apoptosis were observed in the Changweiqing plus L-OHP groups （P 〈 0.05 or P 〈 0.01）.CONCLUSION L-OHP-induced protective autophagy to reduce apoptosis may be the mechanism of drug resistance. Changweiqing can reverse drug resistance, possibly by inhibiting autophagy and regulating the miR-30a/Beclinl signal transduction pathway.