Immune evasion. NO/RNS further contribute to the inhibition of anti-tumor immune responses and the ability of tumors to evade the immune system by increasing T cell apoptosis, and by nitrating TCR on CD8+ T cells, thereby inhibiting their ability to kill antigen-specific tumor cells (Ostrand-Rosenberg and Sinha, 2009; Jia et al., 2010). This evidence concerns the gene CD8A and neoplasm.