Use of phosphodiesterase inhibitors for treating multidrug resistance

Abstract

The present invention relates to methods of treating multidrug resistance in cancerous cells with phosphodiesterase (PDE) inhibitors, e.g., PDE5 inhibitors. More specifically, the invention relates to methods of treating multidrug resistance that arises, e.g., during administration of chemotherapeutic/antineoplastic (anticancer) agents for treatment of cancer, with a PDE5 inhibitor (e.g., sildenafil, vardenafil, and tadalafil). The invention also relates to methods of treating cancer, e.g., multidrug resistant cancer, using a PDE5 inhibitor in combination with an antineoplastic therapeutic agent. Further, the invention relates to pharmaceutical compositions for treating multidrug resistant cancers comprising a PDE5 inhibitor, or a combination of a PDE5 inhibitor and an antineoplastic agent.

1 . A method of treating multidrug resistance in a cancer cell in a subject in need thereof by inhibiting ABCB1 transporter activity, comprising administering to the subject a therapeutically effective amount of a phosphodiesterase 5 (PDE5) inhibitor. 
     
     
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