Synthesis and secretion by mouse 3T3 cells of an inhibitor of cell growth (mIGFBP-3): correlation with cell proliferation. |
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Authors: | L Liu C Blat L Harel |
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Affiliation: | Institut de Recherches Scientifiques sur le Cancer, Villejuif, France. |
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Abstract: | 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. |
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Keywords: | growth inhibitor IGFBP-3 growth factors 3T3 cells |
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