The reason for increased Ki-67 in CD4+ and CD8+ T cells in peripheral blood, but not in the tumor site might be due to the differences in the CTLA-4 blocking antibodies or the different time points for sample harvesting, or lymphocytes may proliferate in lymphoid organs [33] and the peripheral blood compartment before they infiltrate into tumor sites. The gene discussed is CTLA4; the disease is neoplasm.