美国科学家近日利用单个干细胞，建造了小鼠完整的前列腺。这是继2006年科学家在小鼠中利用乳腺干细胞制造出乳腺后，第二次成功地利用单个干细胞制造出完整器官。这一成果代表了干细胞研究和人们对于前列腺发育理解的巨大进步。相关论文10月22日在线发表于《自然》（Nature）杂志上。
之前的研究显示，最接近尿道的前列腺区可能含有丰富的干细胞。在最新的研究中，美国Genentech生物公司的Wei-Qiang Gao和同事将小鼠去势（杀伤了部分前列腺），并注射了睾丸激素以刺激再生。研究人员利用聚合酶链反应分析扫描细胞以寻找多种标记蛋白，其中一些之前在干细胞中发现，另一些已知在前列腺发育中发挥作用。
结果发现，带有CD117+蛋白标记的细胞（先前并不与前列腺干细胞相关），在去势和注射睾丸激素后发生了增殖。当向小鼠肾脏中植入97个带有特殊标记（包括CD117+）的细胞后，其中14个形成了几乎实际大小的前列腺。这些干细胞产生的前列腺与正常前列腺分泌相同的蛋白。
对人类前列腺的蛋白分析同样检测到了CD117+蛋白。Gao说，如果这一蛋白在人体中也是前列腺干细胞标记的话，它将有助于科学家研究前列腺癌是否起源于干细胞出错。
美国匹兹堡大学的再生医学专家Stephen Badylak表示，“这是一项非常重要的发现”，它标志着迈向器官再生目标的重要一步。不过，还需要进行更多的研究，以确保再生器官中的细胞“知道”何时停止生长以及形成怎样的形状。（生物谷Bioon.com）
生物谷推荐原始出处：
Nature，doi:10.1038/nature07427，Kevin G. Leong，Wei-Qiang Gao
Generation of a prostate from a single adult stem cell
Kevin G. Leong1, Bu-Er Wang1, Leisa Johnson1 & Wei-Qiang Gao1
1 Department of Molecular Biology, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA
The existence of prostate stem cells (PSCs) was first postulated from the observation that normal prostate regeneration can occur after repeated cycles of androgen deprivation and replacement in rodents1. Given the critical role of PSCs in maintaining prostate tissue integrity and their potential involvement in prostate tumorigenesis2, it is important to define specific markers for normal PSCs. Several cell-surface markers have been reported to identify candidate PSCs, including stem cell antigen-1 (Sca-1, also known as Ly6a), CD133 (Prom1) and CD44 (refs 3–10). However, many non-PSCs in the mouse prostate also express these markers and thus identification of a more defined PSC population remains elusive. Here we identify CD117 (c-kit, stem cell factor receptor) as a new marker of a rare adult mouse PSC population, and demonstrate that a single stem cell defined by the phenotype Lin-Sca-1+CD133+CD44+CD117+ can generate a prostate after transplantation in vivo. CD117 expression is predominantly localized to the region of the mouse prostate proximal to the urethra and is upregulated after castration-induced prostate involution—two characteristics consistent with that of a PSC marker. CD117+ PSCs can generate functional, secretion-producing prostates when transplanted in vivo. Moreover, CD117+ PSCs have long-term self-renewal capacity, as evidenced by serial isolation and transplantation in vivo. Our data establish that single cells in the adult mouse prostate with multipotent, self-renewal capacity are defined by a Lin-Sca-1+CD133+CD44+CD117+ phenotype.
