Identification and characterization of human gastric cancer stem cells

我们建立了人胃肿瘤组织维持分化和成瘤的异种移植系。利用这些株系，我们鉴定了一个由胃癌干细胞特异性表达的标志物。我们还证实了从新解剖的胃癌中获得的肿瘤干细胞表达了该标志物。此外，我们建立了无血清培养体系，胃癌干细胞在无血清培养体系中增殖形成球体，这是干细胞特有的结构。这些球状细胞表达该抗原，具有很强的致瘤性。我们现在正在研究它们的致瘤性是如何被控制的机制。

We established xenograft lines where human gastric tumor tissues maintain their differentiation and tumorigenesis. Using these lines, we identified a marker which was specifically expressed by gastric cancer stem cells. We also confirmed that the marker was expressed by cancer stem cells which were obtained from newly-dissected gastric cancers. Moreover, we established serum-free culture system where gastric cancer stem cells proliferate to form spheres, structures specific to stem cells. These sphere-forming cells expressed the antigen and were highly tumorigenic. We are now examining the mechanism how their tumorigenicity is controlled.