胰腺星状细胞协同介导胰腺癌细胞神经浸润的分子机制研究

The perineural invasion (PNI) is an important pathological feature of pancreatic cancer. Tumor cells not only infiltrated peri-pancreatic nerve plexus, but also reached distant metastases through the perineural space. PNI is usually associated with poor prognosis, likely because neoplastic cells hidden in the perineural space cannot be removed during tumor resection, leading to disease relapse. Pancreatic stellate cell (PSC) is an important part of the microenvironment of pancreatic cancer. A variety of biological characteristics of tumor cells are related to the interaction of pancreatic cancer cells and PSC. Clinical pathology and our preliminary studies showed that the PSC and pancreatic cancer cells may synergistically mediate the perineural invasion of pancreatic cancer. Our study will be divided into in vitro and in vivo experiments to clarify the important role of PSC in pancreatic tumor microenvironment. Whether and how PSC mediate PNI and the exact mechanism will be clarified. The synergy between the PSC and human pancreatic cancer cells will be also studied. In our study, if the synergy between PSC and pancreatic cancer cells is blocked, the occurrence of PNI in pancreatic cancer can be inhibited. Whether it is proper to regarding PSC as a target for PNI treatment to improve the prognosis of pancreatic cancer? In clinical samples, the pathological and clinical data will be collected. And the preliminary analysis of PSC activation markers and factors associated with PNI-related factor expression will be done to judge the PNI degree, progress and prognosis. Our project is a continuous work of our previous research applied by National Natural Science Fund. The aim is to provide new ideas and experimental basis for research for PNI of pancreatic cancer, and to guide clinical work.

胰腺癌特征性的神经浸润(PNI)，是胰腺癌恶性程度高、预后差的重要原因。胰腺星状细胞(PSC)是胰腺癌微环境的重要组成部分，胰腺癌多种生物学特性与肿瘤细胞和PSC的相互作用有关。胰腺疾病临床病理和我们前期研究均提示，PSC与胰腺癌细胞可能协同介导胰腺癌神经浸润。本项目将通过体内体外实验，阐明胰腺星状细胞PSC作为胰腺癌肿瘤微环境的重要组成部分，是否并以何种机制介导胰腺癌的神经浸润，探讨PSC和人胰腺癌细胞的协同作用及对PNI的影响。研究阻断胰腺星状细胞和胰腺癌细胞的协同作用，能否抑制胰腺癌神经浸润的发生，初步探讨PSC能否作为潜在的治疗胰腺癌神经浸润的靶点，提高胰腺癌的治疗效果。并在临床样本中，结合病理和临床资料，初步分析PSC活化标记物及相关因子、神经浸润相关因子的表达，用于判断胰腺癌神经浸润程度、进展及预后的价值。延续前期工作，为胰腺癌神经浸润研究提供新思路和实验基础，指导临床工作。

胰腺癌特征性的神经浸润(PNI)，是多种因素参与、共同作用的复杂过程，是胰腺癌恶性程度高、预后差的重要原因。胰腺星状细胞(PSCs)是胰腺癌微环境的重要组成部分，胰腺癌多种生物学特性与肿瘤细胞和PSC的相互作用有关，PSC与胰腺癌细胞可能协同介导胰腺癌神经浸润。本研究主要分为体外研究、体内研究和临床研究三部分。在体外，对PSCs进行分离培养及鉴定，体外研究PSCs和人胰腺癌细胞的协同作用，结果提示PSCs可以显著促进胰腺癌细胞的增殖，且促进PNI相关因子明显高表达，同时人胰腺癌细胞对PSCs的分泌功能具有刺激作用。PSCs上清液处理的胰腺癌细胞和神经节共同培养，显著增加胰腺癌细胞的群体生长和神经节的轴突生长，证实PSCs协同胰腺癌细胞促进PNI的发生发展。PSCs协同胰腺癌细胞，会降低胰腺癌的化疗敏感性，提示胰腺癌细胞和PSCs互相促进的协同作用，是胰腺癌化疗不敏感的原因之一。在体内，构建NOD/SCID鼠原位胰腺癌神经浸润模型，观察PNI的发生率和程度，并对瘤体大小实时动态监测，证实胰腺星状细胞协同胰腺癌细胞，不仅促进肿瘤生长，还刺激PNI相关因子高表达，提示阻断胰腺星状细胞和胰腺癌细胞的协同作用，有望抑制胰腺癌神经浸润的发生。胰腺癌坐骨神经旁皮下移植瘤模型的构建，显著提高了胰腺癌的PNI发生率，为胰腺癌的PNI动物实验研究提供了新的简便有效方法。结合临床实际，探讨中晚期胰腺癌患者神经浸润相关腹痛的临床治疗方法及疗效分析，揭示胰腺癌PNI相关性疼痛的临床疗效不能由传统的放疗机制来解释，可能与肿瘤细胞和PSCs的相互作用有关。在临床穿刺和手术切除标本中，结合病理和临床资料，初步分析PSC活化标记物及相关因子、神经浸润相关因子的表达，判断胰腺癌神经浸润程度、进展及预后的价值。证实神经浸润(PNI）的程度和生存期显著相关，性别，肿瘤分化程度，E-cadherin的表达是独立的预后因素。该课题的研究实施，为胰腺癌神经浸润研究提供新思路和实验基础，有助于指导临床工作。