CD8A and cancer: Furthermore, accumulation of senescent CD8+ T cells has also been found in younger patients with chronic viral infections and patients with certain types of cancers, such as lung, breast, or head and neck cancers (Appay et al, 2000; Chen et al, 2009; Meloni et al, 2006; Montes et al, 2008; Tsukishiro et al, 2003; Wolfram et al, 2000).