Cancer stem cells (CSCs), which act as an important bridge between cancer formation and embryonic development, represent a small population associated with tumor initiation, drug resistance, metastasis and recurrence. CSCs have the ability to form spheroids in three-dimensional culture systems. Tumor spheroids derived from CSCs with symmetric and asymmetric division patterns were found to contain highly heterogeneous cell groups. The biological behavior patterns which some CSCs display serve as an important bridge between cancer formation and embryonic development. The cell population in the DU-145 prostate cancer cell line with surface markers CD133+/CD44+ was isolated by FACS. Prostate spheroids were formed by using agarose-coated plates. The morphological characteristics of the cell population within spheroid structure and the expression of Ki-67 and Caspase-3 were investigated by histochemical methods. In this study, we observed that CD133+/CD44+ prostate CSCs form different spheroid structures as well as normal spheroid structures: i) some spheroid structures formed with a highly transparent zone on the outer part of the spheroid, in addition to the normal spheroidal zones and ii) spheroidal structures obtained from prostate CD1334+/CD44+ CSCs that share the same microenvironment are hollow spheres similar to the blastula-like structure in the embryo. These spheroidal structures exhibiting embryo-like properties indicate that the expression of embryonic factors might be reiterated in CSCs. Further investigation of the formation mechanism of the transparent zone and the hollow sphere will shed light on the embryonic origin of prostate cancer and the design of new therapeutic strategies.

癌症干细胞 (CSC) 作为癌症形成和胚胎发育之间的重要桥梁，代表了与肿瘤发生、耐药性、转移和复发相关的小群体。CSCs 有能力在三维培养系统中形成球体。发现来自具有对称和不对称分裂模式的 CSC 的肿瘤球体含有高度异质的细胞群。一些 CSC 表现出的生物学行为模式是癌症形成和胚胎发育之间的重要桥梁。通过 FACS 分离具有表面标记 CD133+/CD44+ 的 DU-145 前列腺癌细胞系中的细胞群。通过使用琼脂糖涂层板形成前列腺球体。通过组织化学方法研究了球状结构内细胞群的形态特征以及Ki-67和Caspase-3的表达。在这项研究中，我们观察到 CD133+/CD44+ 前列腺 CSC 形成不同的球状结构以及正常的球状结构：i）除了正常的球状区域外，一些球状结构在球状体的外部形成了高度透明的区域和ii) 从具有相同微环境的前列腺 CD1334+/CD44+ CSCs 获得的球形结构是类似于胚胎中囊胚样结构的空心球体。这些表现出胚胎样特性的球形结构表明胚胎因子的表达可能在 CSCs 中重复出现。