益胃饮调控胃癌细胞exosomal ITGαvβ5在肝脏转移前微环境形成中的作用和机制研究

中药复方益胃饮是申请人基于柴氏中医肿瘤防治四法而创制，具有延缓胃癌术后复发转移的临床效果，前期研究发现其可抑制胃癌肝转移。靶器官转移前微环境（PMN）是肿瘤转移的关键步骤，癌细胞外泌体可活化肝脏间质细胞、促进肝脏PMN形成。课题组进一步研究发现益胃饮可抑制胃癌外泌体诱导的肝脏Kupffer细胞（KC）活化，推测其可抑制肝脏PMN的形成，但机制不清；ITGαvβ5是外泌体调控肝PMN的关键分子，基因芯片结果提示益胃饮可下调胃癌细胞外泌体ITGαvβ5表达。基于此，本项目拟借助KC-外泌体共培养及胃癌肝转移模型，利用外泌体电穿孔转染等技术，明确益胃饮通过下调胃癌外泌体ITGαvβ5抑制KC活化，阻断肝脏PMN形成；并联合质谱、基因蛋白组学技术和生物信息学分析，探索益胃饮有效成分及其对外泌体ITGαvβ5的调控通路。研究结果旨在提供益胃饮临床应用的实验依据，为中药复方抗肿瘤转移研究提供新的思路。

The traditional Chinese medicine compound “Yiweiyin” which was invented by the applicant based on the four methods of Chai's TCM cancer prevention and treatment has the clinical effect of delaying the recurrence and metastasis of gastric cancer after operation. Our previous studies found that it can inhibit the liver metastasis of gastric cancer. Pre-metastasis microenvironment (PMN) is the key step of tumor metastasis. And exosomes secreted by cancer cells can activate hepatic interstitial cells and promote the formation of PMN in liver. Moreover, we found that “Yiweiyin” can block the activation of Kupffer cell induced by exosomes from gastric cells and down-regulate the expression of tumor-derived exosomal integrin αvβ5 (ITGαvβ5) which plays an vital role in formation of liver PMN. However, the underlying mechanism need further dissection. This project aims to confirm the effect of “Yiweiyin” in regulating tumor-derived exosomal ITGαvβ5 which induces the inhibition of liver pre-metastatic niche formation and subsequently liver metastasis via Kupffer cell-exosomes co-culture assay and xenografted mouse model. Furthermore, we will identify the effective components of “Yiweiyin” and their regulation mechanism in tumor-derived exosomal ITGαvβ5 using mass spectrometry genomic/proteomics techniques. The results will provide the theoretical basis for the clinical application of “Yiweiyin” and new strategies of metastatic gastric cancer.