肝癌细胞系中SP及CD133+细胞的特性分析

Characteristics Analysis of SP and CD133+ Cells in Hepatocellular Carcinoma Cell Lines

近年的研究表明体外培养的肝癌细胞系中存在着少量具有肝癌干细胞功能的细胞群。有研究指出肝癌干细胞存在于侧群细胞(sidepopulation,SP)中,另有研究则发现CD133+细胞是肝癌干细胞的特征。本研究以三种肝癌细胞系(Hep3B、Huh-7和PLC/PRF/5)为对象,利用流式细胞术对其中的SP细胞与CD133+细胞进行了分析,并进一步检测了它们的增殖能力、表型及耐药性等特性。结果显示,肝癌细胞系中存在不同比例的SP细胞和CD133+细胞,且大部分SP细胞呈CD133阳性表达。表型特征分析显示SP细胞表达CK7和CK19,不表达AFP,而CD133+细胞则表达AFP和CK19,却不表达CK7。SP与CD133+细胞都具有较强的增殖能力。另外,相比于其它细胞,SP细胞具有最强的化疗药物抗性。结果表明,肝癌细胞系中SP细胞与CD133+细胞整体特征有一定的区别,提示了它们不同的分化途径。

Recent studies showed that a small population with stem cell functions exists in some cultured liver cancer cell lines. Some studies suggested that hepatocellular carcinoma （HCC） stem cells are enriched in side population（SP）, whereas some other studies found that CD133 is a marker for HCC stem cells. By FACS analysis, SP cells and CD133＋ cells in three human HCC cell lines （Hep3B, Huh-7 and PLC/PRF/5）were examined. In vitro proliferation, phenotypic characteristics, and drug resistance of these cells were further analyzed. Result showed that various levels of SP and CD133＋ cells were existed in HCC cell lines, and the majority of SP cells showed CD133＋ phenotype. SP cells expressed CK7 and CK19, but not AFP, whereas CD133＋ cells expressed AFP and CK19, but not CK7. Both SP and CD133＋ cells contained higher proliferation ability than their counterparts. Furthermore, a highest level of drug resistance was observed in SP cells. Those findings supported the conclusion that SP and CD133＋ ceils showed varied biological characteristics, suggesting that they might be differentiated in diverse pathways.