| Description: |
Human EGF is produced as a long precursor protein of 1207 amino acids which is released by proteolytic
cleavage to give a globular protein of 6.4kDa consisting of 53 amino acids. (1) EGF contains three intramolecular
disuphide bonds, which are essential for its biological activity. It is also known as Human Milk Growth Factor
(HMGF), Prostatic Growth Factor (PGF) and Urogastone. EGF is produced by various organs including the brain,
kidney, salivary gland and stomach, and is found in nearly all bodily fluids at low levels and at higher levels in
saliva, milk, semen and urine. (2)
EGF has been shown to be elevated in patients with brain tumours and to induce differentiation in tumour cell
lines. Also, many epithelial cancers over-express the EGF receptor. Tumour aggressiveness is also associated
with increased expression of EGF receptors. This expression is also high in invasive and disseminated tumours,
therefore many strategies to block the EGF receptor have been studied in an attempt to inhibit tumour
proliferation. (3-6) It has also been proposed that EGF plays an important role in male infertility, as there is a
correlation between the level of circulating EGF, and the number of spermatids in the testis. (7)
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| References:
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1. Bell, G.I. et al, Human EGF precursor: cDNA sequence, expressed in vitro and gene organisation. Nucleic Acid Research. 1986, 14: 8427-8446
2. Carpenter, G. and Wahl, M.I., “The Epidermal Growth Factor Family” in Peptide Growth Factors and Their Receptors I, Sporn MB. And Roberts AB. Eds. Springer-Verlag, New York. 1990, pp 69
3. Saloman, D.S. et al, Epidermal growth factor-related peptides and their receptors in human malignancies. Crit. Rev. Oncol. Hematol. 1995, 19: 183-232
4. Sainsbury, J.R. Epidermal growth factor receptors in human breast cancer. Lancet I. 1985, 364-366
5. Neal, D.E. Epidermal growth factor receptors in human bladder cancer: Comparison of invasive and superficial tumours. Lancet I. 1985, 366-368
6. Modjahedi, H. et al, EGFR blockade by tyrosine kinase inhibitor or monoclonal antibody inhibits growth, directs terminal differentiation and induces apoptosis in human squamous cell carcinoma. Int. J. Oncol. 1998, 13: 335-342
7. Tsutsumi, O. et al, A physiological role of epidermal growth factor in male reproduction function. Science. 1986, 223: 975-977
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