论文部分内容阅读
目的:探索胰腺癌干细胞的存在及其起源。方法:通过分析基因打靶小鼠胰腺腺管上皮异常增生(PanIN)及胰腺癌模型,对LSL-K-rasG12D与Pdx1-Cre产生的小鼠胰腺PanIN和LSL-K-rasG12D、LSL-Tp53R172H与Pdx1-Cre产生的小鼠原发浸润性胰腺癌及胰腺癌肝、肺、胸腺转移组织进行免疫组化分析,并分离、建立PanIN细胞系及胰腺癌和转移癌细胞系,鉴定其体外贴壁依赖性生长及在软琼脂半固体培养基中集落形成。结果:原发胰腺癌及其肝、肺、胸腺转移细胞Tp53和磷酸化-MAPK呈高表达,胰腺癌的肝、肺、胸腺转移灶显示了典型的胰腺腺体及腺管样结构特征;其细胞系在体外培养中快速增殖并在软琼脂中形成肉眼可见集落,提示胰腺癌中含有胰腺癌干细胞。令人感兴趣的是,PanIN的磷酸化-MAPK高表达,在体外培养中的增殖速度与原发及转移性胰腺癌相似,并且能在软琼脂中形成光学显微镜下所见的集落,随着培养时间的延长而集落增大,这不仅提示K-ras的激活突变是胰腺癌的早期分子遗传学改变事件,且提示PanIN细胞已在一定程度上具备了恶性转化的肿瘤行为。结论:本研究首次证实胰腺癌干细胞存在,并提出胰腺癌的发生演变假说:胰腺管上皮细胞—PanIN细胞—胰腺癌干细胞—浸润性和转移性胰腺癌。
Objective: To explore the existence and origin of pancreatic cancer stem cells. Methods: PanIN and LSL-K-rasG12D, LSL-Tp53R172H and Pdx1-P were amplified by LSL-K-rasG12D and Pdx1-Cre in mouse pancreatic ductal adenocarcinoma The primary invasive pancreatic cancer and the metastatic tissues of liver, lung and thymus of mice with pancreatic cancer were analyzed by immunohistochemistry, and the PanIN cell lines and pancreatic cancer and metastatic cancer cell lines were established and their in vitro adherence dependent Sexually grown and colonized in soft agar semi-solid medium. Results: Tp53 and phospho-MAPK were highly expressed in primary pancreatic cancer and its metastatic cells of liver, lung and thymus. Pancreatic adenocarcinoma and duct-like structures of pancreatic carcinoma showed typical pancreatic glandular and duct-like structures. Cell lines rapidly proliferate in vitro and form macroscopically visible colonies in soft agar suggesting pancreatic cancer stem cells in pancreatic cancer. Interestingly, phosphorylation of MAPK in PanIN is highly expressed, its proliferation rate in vitro is similar to that of primary and metastatic pancreatic cancer, and colonies seen under light microscopy can be formed in soft agar as The prolongation of culture time and the increase of colonies not only indicated that the activation mutation of K-ras was an early molecular genetic change event in pancreatic cancer, but also suggested that PanIN cells had a certain degree of malignant transformation tumor behavior. CONCLUSIONS: This study, for the first time, confirms the existence of pancreatic cancer stem cells and proposes the hypothesis that pancreatic ductal epithelial cells-PanIN cells-pancreatic cancer stem cells-invasive and metastatic pancreatic cancer.