摘要
目的 研究 5 -氟尿嘧啶 (5 -Fu)诱导人肝癌HepG2细胞凋亡过程中Fas抗原和bcl-XL 蛋白的表达及意义。方法 采用免疫细胞化学法对 5 -Fu处理的HepG2细胞进行染色 ,运用图像处理和分析系统定量分析Fas抗原和bcl-XL 蛋白表达。流式细胞仪检测抗 -Fas -抗体对氟尿嘧啶诱导人肝癌HepG2细胞凋亡百分率的影响。结果 在未用药处理的对照组细胞Fas抗原呈弱表达(0 .17± 0 .0 3) ,加入 0 .0 1mol L 5 -Fu后Fas阳性表达的细胞数目增加 ,表达强度增强。作用 16h后Fas抗原表达强度达高峰 (0 .4 5± 0 .0 5 ) ,与对照组比较两者有显著差异 (P <0 .0 1)。但在 0 .0 1mol L5 -Fu诱导HepG2细胞凋亡过程中癌基因蛋白bcl-XL 表达逐渐减弱 ,经药物处理 4、8、16、2 4h后 ,其表达分别为 0 .2 8± 0 .0 3、0 .2 0± 0 .0 3、0 .14± 0 .0 3和 0 .0 7± 0 .0 2。癌基因蛋白bcl-XL 的表达与Fas抗原表达呈负相关 (r =- 0 .787,P <0 .0 1)。流式细胞仪分析显示 5 -Fu作用 4 8h后 ,肝癌细胞凋亡百分率为 (16 .2 3± 0 .90 ) % ,而加入抗 -Fas -抗体后细胞凋亡百分率显著上升为 (40 .13± 1.4 5 ) % (P<0 .0 1)。结论 5 -Fu诱导HepG2细胞凋亡是通过Fas依赖途径 ,属于第Ⅱ型Fas信号传导途径。
Objective To explore the expression and biological significance of Fas antigen and bcl-X L oncoprotein in the process of 5-fluorouracil (5-Fu)-induced apoptosis of HepG2 cells in vitro. Methods Immunocytochemical and quantitative image analysis were used for detection of the expression of Fas antigen and bcl-X L oncoprotein in 5-Fu-induced apoptosis of HepG2 cells. The apoptotic rates of human hepatoma cells induced by 5-Fu with or without anti-Fas-antibody (clone CH-11) were measured by flow cytometry. Results Weak expression of Fas antigen was detected in the control cells (0.17±0.03), the number and the intensity of staining of the positive cells increased after treatment with 0.01 mol/L 5-Fu, the expression of Fas antigen increased in accordance with the development of apoptosis and reached the peak 16 hours after exposure to the drug (0.45±0.05). However, the expression of oncoprotein bcl-X L was decreased in the process of 5-Fu-induced apoptosis of HepG2 cells. After 4, 8, 16, 24 h of exposure to 0.01 mol/L 5-Fu, the expression rate of bcl-X L oncoprotein was 0.28±0.03, 0.20±0.03, 0.14±0.03, 0.07±0.02 respectively. There was negative relationship between expression of oncoprotein bcl-X L and Fas antigen (r=-0.787, P<0.01). After 48 h of exposure to 5-Fu, the apoptotic rate of HepG2 cells was (16.23±0.90)%. However, after the HepG2 cells were treated with 5-Fu and anti-Fas-Antibody, the apoptotic rate was increased significantly and reached (40.13±1.45)% (P<0.01). Conclusions 5-Fu induces apoptosis of HepG2 cells via Fas-dependent pathway, which belongs to type Ⅱ Fas signal transduction pathway. The increased Fas antigen expression may be the one that can functionally transduce apoptotic signals. The increased expression of functional Fas antigen and the decreased expression of oncoprotein bcl-X L may involve in the process of 5-Fu induced apoptosis.
出处
《消化外科》
CSCD
2003年第3期168-171,共4页
Journal of Digestive Surgery
