人原发肝细胞癌干细胞表面标志的初步研究

Preliminary research of hepatocarcinoma stem cell markers

目的研究人肝细胞癌干细胞表面标志特征。方法取肝细胞癌手术切除标本,分离、培养肝癌细胞,按照卵圆细胞表面标记(CD34、c-Kit、Thy-1、CK7、CK14、CK19)分选肿瘤细胞,各个表面标记阳性与阴性肿瘤细胞亚群细胞分别异体移植裸鼠,检测体内成瘤能力差异,并且稀释成瘤能力强的细胞亚群,分析低密度下强成瘤能力细胞亚群与相应阴性细胞亚群成瘤差异。结果(1)CD34、c-kit、CK7等3个标记的阳性与阴性肿瘤细胞移植裸鼠后,成瘤能力差异显著(P<0.05)。(2)在低细胞密度下,CD34-、CK7+、c-kit+肿瘤细胞亚群成瘤能力仍强于对应阴性或阳性肿瘤细胞亚群。结论(1)人原发性肝细胞癌肿瘤细胞中存在成瘤能力差异巨大的肿瘤细胞亚群。CD34-、CK7+、c-kit+可能是人肝细胞癌干细胞的部分表面标记特征。

Objective To study human hepatocarcinoma stem cell markers. Methods Tumor tissue samples were obtained from 8 patients with hepatic cellular cancer undergoing surgical tumor resection and the tumor cells were cultured with primary tissue culture in vitro. The cell subpopulations with each marker were isolated from the tumor cells by immunopanning using oval cell markers （CD34, c-kit, Thy-1, CK7, CK19, CK14）. The cells of each phenotype were injected into nude mice to measure their ability of tumor formation and the tumor mass was weighed one month aider implantation. The tumorigenic subpopulations of the cells were injected into the nude mice again in 1/4 or 1/10 of their original densities to further analyze their ability of tumor formation. Results Among all the cell subpopulations, those positive for CD34, c-kit and CKT, respectively, showed marked difference from the negative cells in their ability of proliferation and tumor formation. The CD34, c-kit^＋ and CK^7- subpopulations of the cells exhibited strong capacity of tumor formation even in only 1/4 or 1/10 of their original density. Conclusions There are heterogeneous subpopulations within human hepatocarcinoma with observable difference in tumor formation ability. The strong tumor formation ability of CD34^-, c-kit^- and CK7^-subpopulation of the cells suggests that CD34^-, c-kit^- and CK^- represent part of the surface markers of hepatocarcinoma stem cells.