Bowman-Birk protease inhibitor reduces the radiation-induced activation of the EGF receptor and induces tyrosine phosphatase activity

• Published in: International journal of radiation biology 1998, Vol.73 (2), p.157-162
• Main Authors: GUEVEN, N, DITTMANN, K, MAYER, C, RODEMANN, H. P
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biological effects of radiation; Enzyme Induction - drug effects; Enzyme Induction - radiation effects; ErbB Receptors - drug effects; ErbB Receptors - radiation effects; Fundamental and applied biological sciences. Psychology; Humans; Protein Tyrosine Phosphatases - biosynthesis; Protein Tyrosine Phosphatases - drug effects; Protein Tyrosine Phosphatases - radiation effects; Radiation-Protective Agents - pharmacology; Radioprotection; Space life sciences; Tissues, organs and organisms biophysics; Trypsin Inhibitor, Bowman-Birk Soybean - pharmacology
• ISSN: 0955-3002; 1362-3095
• DOI: 10.1080/095530098142536

Purpose: To investigate the molecular action of the radioprotective Bowman-Birk protease inhibitor (BBI) on radiation-induced tyrosine kinase activity. Materials and methods: Radiation-induced activation of tyrosine kinases and phosphatases was measured in normal human skin fibroblasts by in vitro kinase assays after pre-incubation with BBI. Results: Pre-incubation with BBI resulted in a time-dependent block of the radiation-induced activation of tyrosine kinases. Whilst radiation-induced pp60c-Src activity was not modulated due to BBI pre-treatment, activation of epidermal growth factor receptor (EGFR) was inhibited. Additionally, pre-incubation with BBI resulted in enhanced tyrosine specific phosphatase (PTP) activity. Conclusions: BBI might exert its radioprotective activity by stabilizing specific tyrosine-phosphatases that interfere with EGFR activation in response to radiation exposure.