Fig. 3. The influence of mutant KRAS on the tumour immune microenvironment.
Activating KRAS mutations have numerous implications for the tumour immune microenvironment87,156, including activation and recruitment of macrophages, polarization of M1 to M2 macrophages, and suppression of CD8+ T cells via effects on MHC–T cell receptor (TCR) and PD-L1–PD-1 signalling as well as via activation of myeloid-derived suppressor cells (MDSCs) and regulatory T (Treg) cells. Together, these alterations in the tumour microenvironment present opportunities for intervention in the treatment of KRAS-mutated malignancies, and pertinent examples are provided. DC, dendritic cell; ICAM1, intercellular adhesion molecule 1.