摘要目的 观察胃癌中基质细胞源性因子-1α/CXC趋化因子受体-4(SDF-1α/CXCR4)轴经由PI3K/Akt信号通路对下游分子CD133表达及其活性的影响.方法 免疫细胞化学染色检测胃癌KATO -Ⅲ细胞株中CXCR4、Akt、p-Akt及CD133的表达.分别用SDF-1α、AMD3100及LY294002作用于胃癌KATO -Ⅲ细胞株,半定量酶链聚合反应(PCR)检测CXCR4 mRNA和CD133mRNA的表达变化,蛋白免疫印迹法检测CXCR4、Akt、p-Akt及CD133蛋白的表达变化.结果 免疫细胞化学染色证实KATO -Ⅲ细胞呈CXCR4、Akt、p-Akt及CD133阳性表达.SDF-1α组中,CXCR4蛋白(0.980±0.083)、p-Akt蛋白(0.770±0.071)及CD133蛋白(0.890±0.078)表达与对照组(0.750±0.042、0.680±0.038、0.720±0.034)比较明显增高(P＜0.05).与对照组(0.540±0.036、0.520±0.034)比较,CD133 mRNA(0.890±0.061)表达明显增高(P＜0.05).AMD3100组与对照组(0.750±0.042、0.680±0.038、0.720 ±0.034)比较,CXCR4蛋白(0.430±0.055)、p-Akt蛋白(0.350±0.050)及CD133蛋白(0.110±0.060)表达显著下降(P＜0.05).LY294002组中,p-Akt蛋白(0.100 ±0.033)、CD133蛋白(0.440±0.055)表达与对照组(0.680±0.038、0.720±0.034)比较显著下降(P＜0.05).同时,与对照组(0.540±0.036)比较,CD133mRNA(0.310±0.021)表达差异有统计学意义(P＜0.05).结论 刺激或抑制SDF-1α/CXCR4轴可经由PI3K/Akt信号通路上调或下调CD133表达.

abstractsObjective To observe the effects of stromal cell derived factor/CXC chemokine receptor (SDF-1α/CXCR4) axis on the expression of CD133 via PI3K/Akt signaling pathway in gastric cancer (GC) in vitro.Methods The morphological expression of CXCR4,Akt,p-Akt and CD133 in KATO-Ⅲ cells were detected by using immunocytochemistry.SDF-1α,AMD3100 and LY294002 were respectively used to stimulate/inhibit KATO-Ⅲ cells.The semi-quantitative enzyme-linked polymerization assay for CXCR4 and CD133 mRNA expression was applied.The expression levels of CXCR4,Akt,p-Akt and CD133 proteins were detected by using Western blotting.Results Positive staining of CXCR4,Akt,p-Akt and CD133 was observed in the cultured cells.The expression levels of CXCR4 protein (0.980 ±0.083),p-Akt protein (0.770 ± 0.071 ),and CD133 protein ( 0.890 ± 0.078 ) were significantly higher ( P ＜0.05 ) in SDF-1α group than in control group (0.750 ± 0.042,0.680 ± 0.038,0.720 ± 0.034 respectively).The expression levels of CD133 mRNA (0.890 ± 0.061 ) were significantly higher ( P ＜ 0.05 ) in SDF-1α group.In AMD3100 group,the expression levels of CXCR4 protein (0.430 ±0.055 ),p-Akt protein (0.350 ±0.050) and CD133 protein (0.110 ±0.060) were decreased significantly as compared with those in control group (0.750 ±0.042,0.680 ±0.038,and 0.720 ±0.034 respectively,P ＜0.05).In LY294002 group,the expression levels of p-Akt protein (0.100 ± 0.033) and CD133 protein (0.440 ±0.055) were decreased significantly as compared with those in control group (0.680 ±0.038 and 0.720 ±0.034 respectively,P ＜0.05) ; In comparison with that in control group (0.540 ±0.036),CD133 mRNA (0.310 ± 0.021 ) was decreased significantly (P ＜ 0.05 ).Conclusion The axis of SDF-1α/CXCR4 stimulated or inhibited can up-regulate or down-regulate the CD133 expression via PI3K/Akt signaling pathway in GC in vitro.