Abstract
In this “enlightened” era of drug development, molecular targets are validated on the basis of their relevance to specific disease states, and screening assays are developed to identify small molecule-or peptide-derived modulators of the selected target’s function. However, the more classical paradigm, in which the clinical application of new compounds frequently preceded detailed studies of their molecular mechanisms of action, has not been entirely abandoned. Relevant examples are the natural product immunosuppressive agents, cyclosporine A, FK506, and rapamycin. These drugs (cyclosporine A and FK506 in particular) had already made indelible marks on the clinical field of organ transplantation by the time that bench scientists had begun to unravel the molecular pharmacology underlying their effects on immune responses. Remarkably, the insights provided by basic investigations into the cellular mechanisms of action of the immunosuppressants have been as impressive as the results obtained with these drugs in the clinical arena. In each case, the availability of the immunosuppressant enabled investigators to uncover novel and largely unexpected pathways of intracellular signaling. Ongoing research using cyclosporine A, FK506, and rapamycin as pharmacologic probes continues to yield new information relevant to the clinical management of organ transplants, autoimmune diseases, inflammation, and even cancer.
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Abraham, R.T. (2000). Mammalian target of rapamycin: Immunosuppressive drugs offer new insights into cell growth regulation. In: Letts, L.G., Morgan, D.W. (eds) Inflammatory Processes:. Progress in Inflammation Research. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-8468-6_5
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DOI: https://doi.org/10.1007/978-3-0348-8468-6_5
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