Characterization of tumor-infiltrating CXCR5+CD45RA−CD4+ T cells in 12 pairs of matched tumor and para-tumor tissues showed that the population of CXCR5+CD45RA− cells among CD4+ T cells was higher in tumor tissues than in para-tumor tissues (P = 0.012) (Figure 3A and 3B). The gene discussed is CD4; the disease is neoplasm.