Protein kinase C (PKC) comprises a family of 10 serine/threonine kinases divided into 3 subfamilies: classical, novel and atypical. These isoenzymes represent one of the major mediators of signal transduction, and most may be associated with several pathogenic processes including malignant transformation or cancer and metastasis. Moreover, some activated isoenzymes are also involved in other diseases such as infarct, rejection due to incomplete histocompatibility in organ transplantation, pain, diabetic macular edema, etc. Here, we review several patents related to inhibitors of PKC that represent a new and promising strategy for the prevention and treatment of these illnesses. Among these inhibitors, we included antisense oligonucleotides as another useful strategy to treat infectious and autoimmune diseases associated with misregulated expression of PKC and tumour necrosis factor alpha (TNF-α). On the other hand, two different activators of PKC and their applications related to neurodegenerative diseases have also been reviewed in this work.