Kinase

Definition: An enzyme that adds phosphate groups to another molecule. Many of the key regulatory proteins in the control of gene expression are targets of kinases. The addition of a phosphate group to a protein by a kinase can alter the activity of the protein and are often used as molecular on/off switches. For example, the retinoblastoma tumor suppressor gene is ‘off’ when phosphate groups are added to the protein at specific locations. Removal of the phosphate groups turns the protein ‘on’. Enzymes that remove phosphate groups are known as phosphatases. Note that all enzymes, regardless of function, end in ASE

Protease

Definition: An enzyme that cleaves other proteins. A variety of proteases found in our digestive system break down the proteins we eat into sizes that can be absorbed. Proteases secreted by or associated with cancer cells allow them to digest their way through the tissues that contain them and allow them to spread or metastasize.

Nuclear Receptor Targeted

GPCR Targeted

Ion Channel Targeted

definitions from cancerquest.org