In a similar vein, Gu-Trantien et al. (45) have also recently observed that the presence of breast cancer infiltrating follicular CD4+ T helper cells (Tfh; expressing CD200, FBLN7, ICOS, SGPP2, SH2D1A, TIGIT, and PDCD1/PD-1, and producing the CXCL13 chemokine) may be directly correlated with; (i) the degree of tumor-infiltrating lymphocytes (TIL), (ii) the formation of TLO-like structures in cancer tissue, and (iii) improved patient clinical response to pre-operative chemotherapy and/or post-surgical disease-free survival. Here, PDCD1 is linked to breast cancer.