ATP-binding cassette (ABC) transporters are transmembrane efflux transporters 
mediating the extrusion of an array of substrates ranging from amino acids and 
lipids to xenobiotics, and many therapeutic compounds, including anticancer 
drugs. The ABC transporters are also recognized as important contributors to 
pharmacokinetics, especially in drug-drug interactions and adverse drug effects. 
Drugs and xenobiotics, as well as pathologic conditions, can influence the 
transcription of ABC transporters, or modify their activity or intracellular 
localization. Kinases can affect the aforementioned processes for ABC 
transporters as do protein interactions. In this review, we focus on the ABC 
transporters ABCB1, ABCB11, ABCC1, ABCC4, and ABCG2 and illustrate how kinases 
and protein-protein interactions affect these transporters. The clinical 
relevance of these factors is currently unknown; however, these examples suggest 
that our understanding of drug-drug interactions will benefit from further 
knowledge of how kinases and protein-protein interactions affect ABC 
transporters.