Platelet-Derived Growth Factor Increases the Activity of the Promoter of the Insulin-like Growth Factor-1 (IGF-1) Receptor Gene

Differential Regulation of Insulin-like Growth Factor-I (IGF-I) Receptor Gene Expression by IGF-I and Basic Fibroblastic Growth Factor

“…Both growth factors increase IGF-IR gene expression. It has been shown that PDGF stimulates IGF-IR promoter transcriptional activity (15). Likewise, we show in the present study that bFGF stimulates IGF-IR gene expression by activating promoter activity.…”

“…The promoter activity of this region has been previously characterized and several cis-acting regulatory elements have been described, including EGR/WT1 binding sites (34), Sp1 binding sites (35), a PDGF response region (15) and a potential FGF response region (this study). In addition, the IGF-IR promoter contains a sequence between nucleotides Ϫ583 and Ϫ555, which is similar to a putative IGF-I response element described in the elastin gene that mediates activation of the elastin promoter by IGF-I (36).…”

“…Similarly, PDGF increases IGF-IR gene expression and ligand binding in cells in culture (14), and this effect is due, at least in part, to PDGF stimulation of IGF-IR gene transcriptional activity. This transcriptional effect is mediated by a ϳ100-base pair (bp) region located immediately upstream of the transcription start site (15).…”

Polymorphisms of genes coding for insulin-like growth factor 1 and its major binding proteins, circulating levels of IGF-I and IGFBP-3 and breast cancer risk: results from the EPIC study

“…It is difficult to interpret these associations, with either IGFBP-3 levels or cancer risk, as for none of these SNPs is there any evidence to suggest a possible functional role. Little appears to be known about what genomic elements are involved in the regulation of IGF1 transcription, except for a region immediately upstream of the transcription start (Porcu et al, 1994;Rubini et al, 1994), which however harbours no known genetic variation. We have not typed a CA repeat polymorphism located in the 5 0 region of IGF1, between SNPs rs35767 and rs2162679, which has been frequently included in previous studies.…”

Tendon Healing with Growth Factors

“…Several studies have shown that IGF-I is locally increased during and after inflammation following soft tissue injury, both at the mRNA and protein levels, and is associated with a corresponding up-regulation of its receptors (Bos et al, 2001;Edwall et al, 1989;Fortier et al;Molloy et al, 2003;Rubini et al, 1994Sciore et al, 1998Vogt et al, 1998). James mentioned, that Insulin-like growth factor-1 may be stored as an inactive precursor protein in normal tendon and, upon injury, enzymes release the growth factor to exert its biological activity.…”