RAS-effector protein-protein interface (RAS-effector PPI)

RAS proteins, including the KRAS, HRAS, and NRAS isoforms, are small GTPases that function as molecular switches in essential signal transduction pathways. In their active, GTP-bound state, RAS proteins interact with various downstream effector proteins, such as RAF kinases, PI3K, and RALGDS, through specific protein-protein interfaces (PPIs) to regulate cell growth, survival, and differentiation (1.2.3, 1.3.1). Mutations that lock RAS in a constitutively active state are found in approximately 30% of human cancers, particularly in pancreatic, colorectal, and lung malignancies, leading to uncontrolled oncogenic signaling (1.2.1, 1.5.1). Targeting the RAS-effector PPI represents a direct strategy to block these signals by preventing the physical association between RAS and its effectors (1.3.2, 1.4.1). Historically, these interfaces were considered undruggable due to their large, flat surface areas and the lack of deep binding pockets typical of enzymes or receptors (1.4.1, 1.5.5). However, recent therapeutic advances have introduced small-molecule inhibitors, peptidomimetics, and molecular glues, such as RMC-6236, which recruit chaperone proteins like cyclophilin A to sterically hinder effector binding (1.4.1). These agents aim to selectively disrupt oncogenic RAS signaling while minimizing the impact on normal cellular functions, though challenges remain regarding the inhibition of wild-type RAS and the emergence of resistance (1.3.1, 1.5.5).

Other names

RAS-effector interactionRAS-effector binding siteRAS-effector complexRAS-RAF interfaceRAS-PI3K interfaceRAS-RALGDS interface

Inhibition of protein-protein interaction by competitive binding to the RAS effector binding domain (EBD) or through molecular glue mechanisms that recruit chaperones to sterically block the interface.