Gordeeva O F
Ontogenez. 2012 Jul-Aug;43(4):268-77.
Pluripotent stem cells are able to proliferate indefinitely and differentiate in vitro into various cell types. However, in most cases in vitro differentiation of the pluripotent stem cells is asynchronous and incomplete, and the residual undifferentiated cells can initiate teratoma development after transplantation into recipients. These features of the pluripotent stem cells are the major issue for development of safe cell therapy technologies based on pluripotent stem cells. Considering significant resemblance of growth rates of pluripotent stem and cancer cells we investigated antiproliferative and cytotoxic effects of different type cytostatics (mitomycin C, etoposide, vinblastine and cycloheximide) on the undifferentiated and differentiating mouse embryonic stem cells, embryonic germ cells, blastocyst and on mouse embryonal teratocarcinoma cells and mouse embryonic fibroblasts. The findings showed that all cytostatics used induced both antiproliferative effects and acute toxic processes in undifferentiated pluripotent stem cells and embryonal teratocarcinoma cells whereas these effects were less in differentiating embryonic stem cells and embryonic fibroblast. Moreover, the trophoblast cells of mouse blastocysts were less sensitive to damaging effects of cytostatics than inner cell mass cells. The examination of deferred effects ofcytostatics revealed that the effects ofmitomycin C, etoposide and vinblastine, but not cycloheximide, were irreversible because survived cells were not able to proliferate. Nevertheless, the numbers of embryonic fibroblasts exposed to etoposide or vinblastine remained unchanged while vast majority of undifferentiated pluripotent cells treated underwent apoptosis. Thus, diverse effects of etoposide and vinblastine on the undifferentiated pluripotent stem cells and differentiated embryonic cells allow us to consider these cytostatics and their analogs as drug-candidates for selective elimination of the residual undifferentiated pluripotent stem cells from population of differentiating cells. These findings demonstrate for the first time the possibility of selective elimination of undifferentiated pluripotent stem cells using cytostatic drugs approved for clinic practice. However, to improve effectiveness and safety of this approach and to prevent mutagenic, carcinogenic and teratogenic effects on undifferentiated pluripotent stem cells and their differentiated cell derivatives large-scale studies ofcytostatic effects using different experimental design and active doses must be performed.
多能干细胞能够无限增殖并在体外分化为各种细胞类型。然而，在大多数情况下，多能干细胞的体外分化是异步且不完全的，残留的未分化细胞在移植到受体后可引发畸胎瘤的形成。多能干细胞的这些特性是基于多能干细胞的安全细胞治疗技术发展的主要问题。考虑到多能干细胞与癌细胞生长速率的显著相似性，我们研究了不同类型的细胞抑制剂（丝裂霉素C、依托泊苷、长春碱和环己酰亚胺）对未分化和正在分化的小鼠胚胎干细胞、胚胎生殖细胞、囊胚以及小鼠胚胎性癌细胞和小鼠胚胎成纤维细胞的抗增殖和细胞毒性作用。研究结果表明，所有使用的细胞抑制剂在未分化的多能干细胞和胚胎性癌细胞中均诱导了抗增殖作用和急性毒性过程，而在正在分化的胚胎干细胞和胚胎成纤维细胞中这些作用则较弱。此外，小鼠囊胚的滋养层细胞对细胞抑制剂的损伤作用比内细胞团细胞更不敏感。对细胞抑制剂延迟效应的检测表明，丝裂霉素C、依托泊苷和长春碱的作用是不可逆的，因为存活的细胞无法增殖。然而，暴露于依托泊苷或长春碱的胚胎成纤维细胞数量保持不变，而绝大多数接受处理的未分化多能细胞发生了凋亡。因此，依托泊苷和长春碱对未分化多能干细胞和分化胚胎细胞的不同作用使我们能够将这些细胞抑制剂及其类似物视为从分化细胞群体中选择性消除残留未分化多能干细胞的候选药物。这些发现首次证明了使用已批准用于临床实践的细胞抑制剂选择性消除未分化多能干细胞的可能性。然而，为了提高这种方法的有效性和安全性，并防止对未分化多能干细胞及其分化细胞衍生物产生诱变、致癌和致畸作用，必须使用不同的实验设计和活性剂量对细胞抑制作用进行大规模研究。
