Additionally, the role of B cells in chemotherapy responses has also been explored, identifying an ICOSL+ B cell subset following treatment that enhances anti‐tumor immunity by increasing the effector‐to‐regulatory T cell ratio.[153] Single‐cell sequencing has unveiled substantial heterogeneity within B cell populations,[154, 155] highlighting the need for further research to fully elucidate the distinct functions of B cell subsets and their influence on anti‐tumor immune responses and therapeutic outcomes. Here, ICOSLG is linked to neoplasm.