Frontiers in Immunology (Jul 2019)

A Dual Inhibitor of Cdc7/Cdk9 Potently Suppresses T Cell Activation

  • Elijah W. Chen,
  • Neil Q. Tay,
  • Neil Q. Tay,
  • Neil Q. Tay,
  • Joanna Brzostek,
  • Nicholas R. J. Gascoigne,
  • Nicholas R. J. Gascoigne,
  • Nicholas R. J. Gascoigne,
  • Vasily Rybakin,
  • Vasily Rybakin

DOI
https://doi.org/10.3389/fimmu.2019.01718
Journal volume & issue
Vol. 10

Abstract

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T cell activation is mediated by signaling pathways originating from the T cell receptor (TCR). Propagation of signals downstream of the TCR involves a cascade of numerous kinases, some of which have yet to be identified. Through a screening strategy that we have previously introduced, PHA-767491, an inhibitor of the kinases Cdc7 and Cdk9, was identified to impede TCR signaling. PHA-767491 suppressed several T cell activation phenomena, including the expression of activation markers, proliferation, and effector functions. We also observed a defect in TCR signaling pathways upon PHA-767491 treatment. Inhibition of Cdc7/Cdk9 impairs T cell responses, which could potentially be detrimental for the immune response to tumors, and also compromises the ability to resist infections. The Cdc7/Cdk9 inhibitor is a strong candidate as a cancer therapeutic, but its effect on the immune system poses a problem for clinical applications.

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