Comparing B cell subsets between mTNBCchemo_naive patients to HDs revealed a significant reduction in non-switched B cells and plasmablast-like cells (Fig. 4e, f), but not IgM only—and memory B cells, suggesting that the reduced differentiated B cell subsets we identified (Fig. 3) were partly cancer-driven and partly impacted by prior chemotherapy. This evidence concerns the gene CD40LG and cancer.