吉西他滨白蛋白纳米微球（GEM-ANPs）提升药物疗效并干预胰腺癌细胞耐药的“双通道”机制研究

Gemcitabine (GEM) is the first choice for the treatment of pancreatic cancer, but its’ Inherent and acquired drug resistance are the difficult problem to be solved. In vitro and in vivo experiments, the gemcitabine loaded albumin nanoparticles (GEM-ANPs) was invented by our applicant team, and not only showed better efficacy than GEM, but also decreased the drug resistance of pancreatic cancer cells. The preliminary study focused on this special phenomenon found that: GEM-ANPs does not rely on nucleoside transporter and could carry GEM into the cell, GEM-ANPs could hinder the ABC transporter family to efflux GEM simultaneously. Accordingly, this study put forward the hypothesis that GEM-ANPs has the function of "dual channel" intervention between GEM and cancer cells. This project intends to construct cell dynamics and transplanted tumor animal models, through RNA interference, lentivirus transfection, fluorescence confocal imaging techniques for investigation of endocytosis, intracellular ATP content and epigenetic changes related to drug resistance in vitro and in vivo, to analysis the molecular mechanism of "double channel" caused by GEM-ANPs. The implementation of this project will be a supplement and update to the existing pharmacokinetics, and will provide new ideas and strategies in order to improve the durg efficacy and interfere drug resistance of pancreatic cancer.

胰腺癌化疗首选药物吉西他滨（GEM）存在严重的原发性和获得性耐药,是临床治疗亟需解决难题。申请人所在团队前期自主研发的吉西他滨白蛋白纳米微球（GEM-ANPs）在体内外实验中不仅表现出药效优于GEM，并具有减弱胰腺癌细胞对GEM耐药的功能。课题组前期聚焦此特殊作用展开研究后发现：GEM-ANPs存在不依赖核苷转运体将GEM载入细胞并阻碍ABC转运蛋白家族外排GEM的作用可能。据此，本课题提出假设：GEM-ANPs具有干预GEM出入细胞的“双通道”作用。本课题拟构建细胞动力学和移植瘤动物模型，通过RNA干扰、慢病毒转染、荧光共聚焦显像等技术手段，针对细胞内吞作用、细胞ATP含量和耐药相关表观遗传等对GEM-ANPs存在的“双通道”干预作用进行体内外检验，并解析其分子机制。本课题实施将是对现有药代动力学的理论补充和更新，为改善胰腺癌药效和干预胰腺癌细胞耐药提供新思路、新策略。

在胰腺癌的治疗中，化疗首选药物吉西他滨（GEM）存在的原发性和获得性耐药现象是亟需解决的关键问题。申请人所在团队前期自主研发的吉西他滨白蛋白纳米微球（GEM-ANPs）在体内外实验中不仅表现出药效优于GEM，还被发现具有潜在减弱胰腺癌细胞耐药的功能。聚焦此特殊作用展开机制研究和解析是对已有药代动力学理论的重要补充和更新，还将为干预胰腺癌细胞耐药提供新思路。. 我们揭示了GEM-ANPs能在GEM药物入胞转运体低表达的情况下促进GEM顺利进入到胰腺癌细胞内，并探究了GEM-ANPs克服入胞通道耐药而增强吉西他滨药效的作用机制；我们同时揭示了GEM-ANPs能在GEM药物外排转运体高表达的情况下减少GEM外排从而使胰腺癌细胞克服出胞通道耐药，并进一步探究了潜在机制；最后在移植瘤动物模型上验证了GEM-ANPs在体内对胰腺癌细胞耐药存在的“双通道”干预作用。本课题通过多学科交叉与协作，为改善胰腺癌药效这一目标提供了策略依据和理论支撑。