Itaconate promotes an unexpected tumor immune escape mechanism. Cancer cell Itaconate is a metabolite produced by macrophages upon infection and acts as an antimicrobial molecule. In this issue of Cancer Cell, Lin et al. find that itaconate produced by tumor-associated macrophages is taken up by cancer cells via the transporter solute carrier family 13 member 3 (SLC13A3), promoting resistance to immune checkpoint inhibitors. 10.1016/j.ccell.2024.10.011

Mutation burden and anti-PD-1 outcomes are not universally associated with immune cell infiltration or lymphoid activation. Cancer cell Analysis of 27,810 patients with advanced cancers treated with anti-PD-1/L1 therapies shows that immune gene signatures or immune cell infiltration is not universally associated with mutation burden or long-term survivors after immunotherapies across cancer entities. Thus, immunological stratification of tumors has limited bearing on the immunogenicity of tumors or immunotherapy outcomes. 10.1016/j.ccell.2024.10.017