A small molecule inhibitor of IRE1α RNAse activity markedly diminished Il6 and Arg1 transcription, suggesting that transcellular regulation of myeloid immune cells by aneuploid cancer cells is also IRE1α‐XBP1 dependent (Cubillos‐Ruiz et al, 2015; Batista et al, 2020). The gene discussed is ARG1; the disease is cancer.