The level of tyrosine kinase activity regulates the expression of p21/WAF1 in cancer cells.

  • Authors:
    • K B Reddy
    • V G Keshamouni
    • Y Q Chen
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  • Published online on: August 1, 1999     https://doi.org/10.3892/ijo.15.2.301
  • Pages: 301-307
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Abstract

It is well documented that epidermal growth factor (EGF) inhibits proliferation of A431 and MDA-468 cells via activation of p21/WAF1. In the present study, we have shown that treatment of MDA-468 and A431 cells that express high levels of EGFR with 100 ng/ml of EGF leads to 14.9-fold increase in epidermal growth factor receptor (EGFR) autophosphorylation and high levels of p21/WAF1-induction (6. 7-fold), down regulation of cdk2 activity and growth arrest. When MDA-468 or A431 cells were simultaneously treated with 100 ng/ml EGF and RG13022, a relatively specific tyrosine kinase inhibitor, there was a significant reduction in p21/WAF1 levels. In contrast, when MDA-468, A432 cells that are treated with low levels of EGF (10 ng/ml) or other cells which express low to moderate levels of EGFRs such as MCF-7, MCF-10A, MDA-231 and SKBR-3 breast cells were exposed to 100 ng/ml of EGF there was a 3.8-fold increase in EGFR autophosphorylation, leading to 1.6-fold induction of p21/WAF1 and increased cell proliferation. These results suggest that the level of EGFR tyrosine kinase activity may regulate p21/WAF1 induction in cancer cells.

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August 1999
Volume 15 Issue 2

Print ISSN: 1019-6439
Online ISSN:1791-2423

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APA
Reddy, K., Keshamouni, V., & Chen, Y. (1999). The level of tyrosine kinase activity regulates the expression of p21/WAF1 in cancer cells.. International Journal of Oncology, 15, 301-307. https://doi.org/10.3892/ijo.15.2.301
MLA
Reddy, K., Keshamouni, V., Chen, Y."The level of tyrosine kinase activity regulates the expression of p21/WAF1 in cancer cells.". International Journal of Oncology 15.2 (1999): 301-307.
Chicago
Reddy, K., Keshamouni, V., Chen, Y."The level of tyrosine kinase activity regulates the expression of p21/WAF1 in cancer cells.". International Journal of Oncology 15, no. 2 (1999): 301-307. https://doi.org/10.3892/ijo.15.2.301