Son of sevenless homolog 1 (Sos1) is a guanine nucleotide exchange factor (GEF) that directs the exchange of Ras-GDP to Ras-GTP by binding to SH3 domains of the growth factor receptor-bound protein 2 (Grb2), leading to the activation of ERK. Ras inhibitory peptide is a synthetic peptide that contains the sequence PVPPR, which corresponds to a region within human Sos1 that interacts with an SH3 domain of Grb2. It specifically blocks the interaction of the GEF with Grb2, preventing an interaction that is essential for Ras activation by receptor tyrosine kinases, including epidermal growth factor receptor.
KRA-533 is an effective KRAS agonist that targets the GTP/GDP binding pocket within the KRAS protein, inhibiting GTP cleavage. This leads to accumulation of the active GTP-KRAS form, promoting apoptosis and autophagic death in cancer cells.
Divarasib (GDC-6036) adipate is a selective and highly potent KRAS G12C inhibitor with an impressively low IC 50 value of <0.01 μM, designed for oral administration. It covalently attaches to the switch II (SW-II) pocket in KRAS G12C, irreversibly maintaining the protein in its inactive GDP-bound state [1] [2].