Therapeutic Implications of Targeting AKT Signaling in Melanoma

Figure 3

Schematic representation of PI3 kinase enzymes. PI3 kinases are a group of enzymes involved in regulating cell growth, proliferation, differentiation, motility, and survival. Based on structure and substrate specificity PI3 kinases have been divided into Class I (EC number: 2.7.1.153), Class II (EC number: 2.7.1.154), and Class III (2.7.1.137) enzymes. Class I and II PI3Ks are composed of regulatory and catalytic subunits, whereas Class III contains only catalytic subunit. Depending on the type of subunits, heteromeric Class I PI3Ks are further subdivided into Class IA and Class IB. Whereas Class IA PI3K consists of p85 regulatory subunit and p110 catalytic subunit, the Class IB PI3K is made up of p101 regulatory subunit and p110γ catalytic subunit. Class IA PI3K is the most common PI3Ks implicated in the development of cancers.