Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Exp Cell Res. 2012 Sep 10;318(15):1799-807. doi: 10.1016/j.yexcr.2012.04.011. Epub 2012 Jun 5.
There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation.
越来越多的证据表明，人类实体肿瘤细胞起源于癌症干细胞（CSC）。在癌细胞系中，肿瘤起始的 CSC 主要存在于具有排出 Hoechst 33342 等染料能力的侧群（SP）中。我们发现 Nanog 特异性表达于人类胃肠道（GI）癌细胞的 SP 细胞中。核苷酸测序显示 GI 癌细胞中表达的是 NanogP8 而不是 Nanog。将 NanogP8 转染入 GI 癌细胞系可促进细胞增殖，而用抗 Nanog siRNA 抑制其表达则抑制了增殖。对 60 例原发性 GI 癌组织的免疫组织化学染色显示，NanogP8 蛋白在 3 例中强表达。在这些病例中，NanogP8 尤其在肿瘤的浸润部分、具有 Ki67 表达的增殖细胞中表达。这些数据表明，NanogP8 参与了一部分患者的 GI 癌发生，推测其通过支持 CSC 增殖而发挥作用。
