Mutant Ras proteins (Mutant Ras)

Mutant Ras proteins are among the most common drivers in human oncology, particularly in pancreatic, colorectal, and lung cancers (Simanshu et al., 2017). These proteins arise from point mutations in the KRAS, NRAS, or HRAS genes, most frequently at codons 12, 13, or 61, which lock the GTPase in a constitutively active, GTP-bound state (Prior et al., 2020). This leads to persistent activation of downstream signaling pathways like MAPK and PI3K, driving uncontrolled cell proliferation and survival (Huang et al., 2021). In the context of antigens, these mutant proteins are processed into unique peptides (neoantigens) and presented on the cell surface by Major Histocompatibility Complex (MHC) molecules (Leidner et al., 2022). This presentation allows them to be targeted by the immune system through therapeutic vaccines or engineered T-cell receptor (TCR) therapies (Bear et al., 2020). Recent breakthroughs have also led to the development of allele-specific small molecule inhibitors, such as those targeting the KRAS G12C mutation, which bind to the switch II pocket to stabilize the inactive GDP-bound form (Canon et al., 2019).

Other names

Mutant Ras antigensMutant KRASMutant NRASMutant HRASOncogenic RasRas neoantigens

Small molecule inhibitors (e.g., G12C inhibitors) covalently bind to the switch II pocket of the mutant protein to lock it in the inactive GDP-bound state, thereby inhibiting downstream signaling (Canon et al., 2019). Immunotherapeutic approaches, such as vaccines and TCR-T cell therapies, involve the recognition of mutant Ras peptide fragments (neoantigens) presented on MHC molecules by T-cells, leading to the targeted destruction of tumor cells (Leidner et al., 2022).