In addition, expression levels of markers related to T cell exhaustion, cell survival, senescence, proliferation and differentiation; for example, members of the TOX family, silent information regulator 1 (SIRT1), PRDM1 (gene name for Blimp1), Helios and Ki-67, were also determined in tumor tissues of CRC patients. The gene discussed is PRDM1; the disease is neoplasm.