For example, higher frequencies of CD8 tumor infiltrating T cells are associated with improved clinical outcome and survival (Zhang et al. 2003; Sato et al. 2005), but the presence of T regulatory cells (CD4+ FoxP3+) in tumor tissues is associated with reduced survival and high death hazard in patients with ovarian carcinoma (Curiel et al. 2004). This evidence concerns the gene CD4 and neoplasm.