Protein kinase C inhibitors: a patent review (2010-present)

Introduction: Protein kinase C (PKC) comprises at least 10 isoforms, pivotal in various cellular differentiation processes and in other specific cellular functions. Catalytic subunits of all PKCs are highly conserved which play a central role in the development of kinase-specific inhibitors for the treatment of a number of diseases and also in the drug resistance and immunological disorders. The authors' previous work of reviewing patents of PKC inhibitors is continued in this report. Area covered: Thorough survey on the physiological roles of PKC isoforms and patents filed for PKC inhibitors from 2010 to present representing new and potential strategy for the cure and prevention of disorders due to elevation in various PKC levels is reported. Expert opinion: The PKC isoforms are unique in terms of tissue distribution and an elevation in any isoform level results in different diseased conditions. Different PKC isoforms have high sequence identity but they are involved in different diseases. Crystal structure of few PKC isoforms viz. C1 domain of PKC delta, the C2 domains of PKC alpha and beta, kinase domain and full structure of PKC beta II are known. Identification of more crystal structures and thorough analysis of available structures and information on the PKC ligands will be helpful in the drug designing and development processes.