摘要
目的 研究真皮来源成体多能干细胞体外恶性转化现象及其相关机制。方法 对分离的真皮多能干细胞克隆体外进行连续传代培养 ,观察其生长性状的改变 ,通过裸鼠皮下接种实验观察其是否恶性转化 ;应用基因芯片技术比较转化前后细胞基因表达谱的改变。结果 经过长期体外连续传代培养后 ,真皮多能干细胞可发生恶性转化 ,在裸鼠体内形成肉瘤样组织 ;基因芯片技术检测显示 ,转化后细胞仍表达多种类型细胞特异性基因的转录子 ,提示其仍具有多向分化的潜能 ;但转化后细胞多种增殖相关基因的表达升高 ,代谢反应酶类基因表达升高 ,生长因子和受体的表达下调 ,符合肿瘤细胞的特征 ;c ki ras基因及其相关信号分子的表达上调可能在转化过程中起重要作用 ;初步筛选鉴定了一个与干细胞增殖调控相关的候选基因。结论 体外长期连续传代培养可诱发真皮多能干细胞的恶性转化 。
Objective To study the phenomena and the related mechanisms of malignant transformation of dermis derived multipotential stem cells in vitro . Methods Clonal populations of dermal multipotential stem cells were passaged sequentially in vitro , and the subcutaneous inoculation of cells in nude mice was used for observation of the tumor formation. The transcript profiles of the transformed cells were analyzed by DNA microarray technique. Results Dermal multipotential stem cells underwent spontaneous malignant transformation after serial subculture in vitro . Cells grew out of control, and chromosome number was abnormal. After cells were inoculated subcutaneously into BALB/c nu/nu athymic mice, tumors characterized by fibrous histiocytoma were produced. Immunohistochemistry showed that there were different cell populations for the expression of vimentin, cytokeratin, S 100, and α smooth actin. Detection by DNA microarray technique revealed that the transformed cells expressed multilineage transcripts, indicating that the transformed cells might have the multipotency. Among the differentially expressed genes in transformed cells, most of the up regulated genes were related to the proliferation process, but most of the down regulated genes were growth factors and their receptors. The enhanced expression of the c ki ras gene and its relevant molecules may play important roles in the transformation process. A candidate gene with unknown functions related to the stem cell proliferation was also preliminarily identified. Conclusion Dermal multipotential stem cells can undergo spontaneous malignant transformation in vitro . Further studies of the mechanisms of this process at the molecular level may have significance both in stem cell application and in tumorigenesis.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2004年第1期71-73,共3页
Journal of Third Military Medical University
基金
国家重点基础研究发展规划资助项目 ("973"项目 ) (G19990 54 2 0 5)~~
关键词
干细胞
恶性转化
皮肤
stem cell
malignant transformation
skin
