P7抑制bFGF诱导的3T3细胞增殖的作用机制

研究从噬菌体随机七肽库中筛选得到的新型bFGF拮抗肽 (P7) 抑制bFGF诱导的Balb/c 3T3细胞增殖的作用机制。采用倒置显微镜观察不同浓度P7对细胞形态的影响; 流式细胞术分析P7对细胞周期的影响; Western blotting检测P7对bFGF刺激的Balb/c 3T3细胞中MAPK通路的MEK、Erk1/2信号分子活化水平的影响。结果显示, 在检测的浓度范围内, P7对Balb/c 3T3细胞形态无显著影响; P7可改变bFGF刺激下Balb/c 3T3的细胞周期, 减少S期细胞比率, 使细胞阻滞在G₀/G₁期; 并以剂量依赖的方式下调bFGF激活的MEK、Erk1/2信号分子的磷酸化水平。P7可能通过阻滞细胞在G₀/G₁期, 下调MAPK通路信号分子的活化水平, 从而抑制bFGF诱导的Balb/c 3T3细胞增殖。

Mechanism of inhibitory effect of P7 on 3T3 cell proliferation induced by basic fibroblast growth factor

 To investigate the mechanism of inhibitory effect of a novel bFGF antagonist peptide isolated from the phage display random heptapeptide library on cell proliferation induced by basic fibroblast growth  factor.  The effect of P7 on cell morphology was observed under an inverted microscope.  Flow cytometry was applied to analyze the effect of P7 on cell cycle progress of bFGF-stimulated cells.  The effect of P7 on bFGF-induced activation of MEK and Erk1/2 in MAPK pathway was detected by Western blotting.  The results showed that no significant cell morphology change was observed in the range of detected concentrations of P7.  Cell cycle analysis showed that P7 decreased S-phase cell population and arrested cell cycle at the G₀/G₁ phase of bFGF-stimulated cells.  The results of MAP kinase activation assay indicated that P7 decreased bFGF-induced MEK and Erk1/2 phosphorylation in a dose-dependent manner.  P7 inhibited proliferation of bFGF-stimulated Balb/c 3T3 cells possibly via cell cycle arrest at the G₀/G₁ phase and down-regulation of signal molecular    activation in MAPK pathway.