基于小分子诱导人ES细胞分化肝细胞的肝癌诱导分化策略及其机制研究

项目名称： 基于小分子诱导人ES细胞分化肝细胞的肝癌诱导分化策略及其机制研究

项目编号： No.81472772

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 张培霖

作者单位： 中国人民解放军第二军医大学

项目金额： 72万元

中文摘要： 肝细胞癌（HCC）有发病率高、病情隐匿、预后凶险等特征，目前缺乏有效的治疗方案。肿瘤诱导分化治疗在血液系统肿瘤治疗上有成功先例，但针对HCC分化信号调控系统的特异性分化诱导剂及方法却未见任何报道。根据HCC（干）细胞与ES细胞具同源性和相似性特点，申请者拟研究基于小分子定向诱导ES细胞分化为高纯度的功能性肝细胞的方法和策略，应用于HCC的诱导分化。前期实验结果表明：小分子组合处理多株HCC细胞，3－9天内10－60％凋亡，其余则向成熟细胞方向分化，不再具有肿瘤细胞的生物学行为。HCC干细胞则更易于被诱导凋亡和分化，且该方法对正常肝细胞无损伤。本研究拟完善此方法，深入研究其信号网络通路和关键调控因子及相关调控机理；采用临床肝癌样本和肝癌实验动物模型验证其临床相关性、有效性和普适性。本研究有助于明确肝癌诱导分化机理，为临床诊治肝癌提供理论依据，并可能为临床治疗肝癌提供一种新方法、新药物。

中文关键词： 胚胎干细胞；肿瘤干细胞；肝细胞肝癌；凋亡；分化

英文摘要： Hepatocellular carcinoma (HCC), is the sixth most common malignant disease worldwide and the third greatest cause of cancer-related death. The increasing incidence, the high heterogeneity of HCC, the limited therapeutic options and its resistance to traditional anticancer therapies such as chemotherapy and radiotherapy, and the recurrence and metastasis result in the poor prognosis of HCC. Therefore, development novel therapeutic strategies for HCC treatment are urgent. The observation of cancer stem cell (CSC) led to establish a model in which tumour would arise from rare to moderately frequent cells able to initiate a hierarchy of proliferative and progressively differentiating non-tumourigenic cells. This non-tumourigenic population of cells would then form the bulk of the tumour. In this model, CSC shares similar properties to normal adult stem cells or embryonic stem cell (ESC). These properties include the capacity of self-renewal, the use of key regulatory pathways and the establishment of dynamic epigenetic profiles. Hence, the tumour hierarchical organization would be some level comparable to that found in normal tissue, where genetic and epigenetic changes trigger both cell differentiation and cell fate. Recently, we have developed a novel approach using small molecule combination to efficiently different human ESC to homogenous mature functional hepatocytes. Due to some level similarity of cancer cell and CSC with ESC, we postulated that our protocol for hESC differentiation might also be suitable for HCC differentiation induction. We took several HCC lines to do the same experiments and the primilary data showed that based on the HCC lines,10-60% cell apoptosis in 3-9 days treatment and the left cells differentiate to be matured cell which re-gained its normal morphology and behavior such as reduced proliferation rate, increased ALB and HNF4a expression, non-colonies growth pattern, no longer aerobic glycolysis metabolism. Further analysis revealed that our protocol to induce HCC apoptosis and differentiation was p53 independent and compared to CD133- population, CD133+ HCC (CSC) was much easier to be induced apoptosis and differentiation. These results suggested that hESC differentiation approach also facilitates HCC differentiation. However, what signaling pathway(s) and key regulation factor(s) involve in and work together to induce HCC apoptosis and differentiation? What is the endogenous difference between apoptotic and differentiated HCC? Whether our observation can be confirmed in clinic HCC samples, and whether this small molecule combination can be used for in vitro fresh isolated HCC from clinic and in vivo HCC animal models for apoptosis and differentiation induction? We plan to perform systematic investigation to answer these questions and elucidate the regulation mechanism. Our research results would help to develop a promising novel approach for HCC diagnosis and treatment.

英文关键词： Embryonic stem cell (ESC);Cancer stem cell(CSC);Hepatocellular carcinoma (HCC);Apoptosis;Differentiation