SP25

SP25 is a novel, target-selective modulator of Extracellular Signal-Regulated Kinase 1/2 (ERK1/2) signaling. Unlike traditional ATP-competitive ERK inhibitors, SP25 binds to the FRS (substrate-binding domain) of ERK2, which is responsible for interacting with and activating the transcription factor Activator Protein-1 (AP-1). By targeting this specific interaction, SP25 selectively downregulates the expression of AP-1 components FRA-1 and FosB, leading to a decrease in Cyclin D1 and the inhibition of airway smooth muscle (ASM) cell proliferation. This mechanism aims to treat asthma-related airway remodeling while minimizing the off-target effects and toxicity associated with global ERK pathway inhibition. The compound was developed through computational approaches by researchers at the University of Maryland and Thomas Jefferson University.