Liu L, Blat C, Harel L
Institut de Recherches Scientifiques sur le Cancer, Villejuif, France.
Biol Cell. 1992;76(2):125-30. doi: 10.1016/0248-4900(92)90204-e.
Our results show that stimulation by serum of dense cultures of 3T3 cells rapidly induced increased synthesis of a growth inhibitor (mIGFBP-3) capable of binding IGF. mIGFBP-3 was secreted by stimulated cells immediately after its synthesis, and accumulated in the medium. Accumulation of mIGFBP-3 in the medium increased, as a function of growth factor (bFGF, PDGF, insulin) concentrations and time. bFGF was the best stimulatory factor for both DNA synthesis and accumulation of mIGFBP-3 in the first 24 h of incubation. DNA synthesis was arrested after 48 h of incubation with bFGF when accumulation of mIGFBP-3 was maximal. Since we showed that mIGFBP-3 is able to inhibit bFGF stimulation of DNA synthesis in mouse fibroblasts, it is possible that the accumulation of mIGFBP-3 induces a feedback regulation of cell growth.
我们的结果表明，血清对3T3细胞致密培养物的刺激迅速诱导了一种能够结合胰岛素样生长因子（IGF）的生长抑制剂（小鼠IGFBP-3）合成增加。小鼠IGFBP-3在合成后立即由受刺激的细胞分泌，并在培养基中积累。培养基中小鼠IGFBP-3的积累量随着生长因子（碱性成纤维细胞生长因子、血小板衍生生长因子、胰岛素）浓度和时间的变化而增加。在孵育的前24小时，碱性成纤维细胞生长因子是DNA合成和小鼠IGFBP-3积累的最佳刺激因子。当小鼠IGFBP-3的积累量达到最大时，用碱性成纤维细胞生长因子孵育48小时后DNA合成停止。由于我们发现小鼠IGFBP-3能够抑制碱性成纤维细胞生长因子对小鼠成纤维细胞DNA合成的刺激，因此小鼠IGFBP-3的积累可能诱导了细胞生长的反馈调节。
