化疗耐药是导致胰腺癌预后差的主要原因之一，化疗过程中胰腺癌微环境的动态变化及其对化疗敏感性的影响是目前研究热点，相关分子机制尚不明确。胰腺星形细胞是塑造胰腺癌微环境的主要效应细胞，本课题组前期研究结果显示胰腺星形细胞通过旁分泌作用促进了胰腺癌细胞的多种恶性表型。本项目拟应用肿瘤细胞特异性生物发光成像技术，基于细胞共培养体系和胰腺癌原位移植瘤模型，动态研究化疗过程中胰腺星形细胞对胰腺癌化疗敏感性的影响，筛查和鉴定介导胰腺癌细胞耐药的关键细胞因子，并进一步通过转录组学分析构建两种细胞间的动态基因调控网络，联合基因工程小鼠模型和人源异种移植瘤模型，从分子-细胞-组织多个层面，系统而深入地解析以吉西他滨为代表的化疗药物诱导胰腺星形细胞转录重编程介导胰腺癌耐药的旁分泌机制，以期发现药物敏感性预测新指标，探索多靶标联合干预新策略，为推动胰腺癌个体化治疗最终改善患者预后奠定基础。

Chemoresistance is a major reason for poor prognosis of pancreatic cancer. Recent researches highlight the chemotherapy-induced dynamic changing of microenvironment and its impact on chemosensitivity in pancreatic ductal adenocarcinoma (PDAC), but the underlining mechanisms remain unclear. Pancreatic stellate cell (PSC) represents one of the main effector cells in building the unique microenvironment of PDAC. Our previous data demonstrated that PSC promoted multiple malignant phenotypes of pancreatic cancer cell (PCC) by a paracrine effect. In this project, we aim to systematically clarify how chemotherapy-induced dynamic transformation of PSC in transcriptional levels promotes PCC chemoresistance via paracrine signaling. Firstly, we plan to dynamically study the effects of PSC on chemosensitivity of PCC during gemcitabine treatment based on cellular co-culture system and pancreatic cancer orthotopic xenograft model with a new tumor cell specific bioluminescence imaging (CS-BLI) technique. Then we seek to screen and identify the key cytokine secreted by PSC to induce PCC chemoresistance. Next, transcriptional sequencing of both PSC and PCC will be performed to establish a dynamic gene regulatory network between these two cells, based on which both the regulatory mechanism of the key cytokine secreting in chemotherapy-stressed PSC and the molecular mechanism of the key cytokine inducing chemoresistance in PCC will be investigated in cell lines and animal models. Finally, the genetically engineered mouse models（GEMMs）and patient derived xenograft (PDX) of pancreatic cancer will be employed to screen the potential biomarkers predicting chemosensitivity and evaluate efficacy of possible combined therapy. This study will identify novel biomarkers for drug sensitivity and establish a new strategy for multi-targets intervention to promote personalized therapy and ultimately improve prognosis of pancreatic cancer.