肝素增强佛波酯对人鼻咽癌CNE2细胞的作用：上调c-jun、p53、p21的表达（英文）

目的：观察肝素联合佛波酯对人鼻咽癌细胞的增殖与凋亡的影响及其可能的分子机制。方法：用细胞记数法、流式细胞术观察肝素联合佛波酯对人鼻咽癌细胞的增殖及细胞周期的影响；而用TUNEL、琼脂糖凝胶电泳、Western blot等方法观察肝素与佛波酯联合应用对人鼻咽癌细胞凋亡的作用。结果：肝素与佛波酯联合应用后对鼻咽癌细胞的生长抑制及其凋亡具有显著增强的作用，同佛波酯单独应用于诱导细胞凋亡相比,低剂量的肝素与佛波酯联合应用后发现：TUNEL阳性细胞明显增多；G₁期细胞阻滞，S期细胞明显减少，凋亡率增加；DNA“梯形”变化更加明显；c-jun、p53、p21基因表达明显升高，而c-fos在整个用药过程中没有改变。结论：肝素增强佛波酯对人鼻咽癌细胞的抗增殖及促凋亡，这可能与c-jun、p53、p21的表达上凋有关。

Potentiation of the action of phorbol ester by heparin in human CNE2 cells: Association with enhanced expression of c-jun,p53 and p21

AIM: To measure the effect of addition of hep arin to TPA on cell proli feration and apoptosis in CNE2 cells and investigate the possible molecular mech anisms underlying heparin and TPA interaction on cell proliferation and apoptosi s. METHODS: Cell viability and cell cycle were determined by cel l counting and flow cytometry. Apoptosis was evaluated by terminal deoxynucleotidyl transferase -mediated dUPT nick-end labeling (TUNEL) and agarose gel electrophoresis. The ex pression of c-jun,c-fos,p21 and p53 was examined by Western blot. RESU LTS: TPA alone inhibited CNE2 cell proliferation and evoked apoptosis associated with ty pical morphological changes and DNA fragmentation,which was augmented when hepa rin was added. Compared with TPA or heparin alone,TPA plus heparin obviously en hanced the number of TUNEL-positive cells from 23%±1.2% to 51%±0.9%. After exp os ure to different concentrations of heparin (with or without TPA) for 24 h,CNE2 cells were accumulated G 0/G 1 phase. There was a decrease in the number of ce lls in S phase by the combined heparin and TPA treatment compared to heparin or TPA alone. Western blot analysis revealed that TPA induced the increases in c-jun an d p53,p21 protein expression and the levels were remarkably increased following heparin in combination with TPA treatment,whereas no significant change in c-f os was detected. CONCLUSION: These results suggest that heparin synergistically potentiates the action of TPA in CNE2 cells,which may be associated with the in crease in c-jun protein level and the upregulation of p21,p53 protein expressio n.