CD8A and melanoma: Whiteside’s group has previously reported that in patients with head-and-neck carcinoma or melanoma that circulating bulk CD8+ (but not CD4+) T cells frequently exhibit an early apoptotic phenotype (41–43), which may be related to an increased ratio of Bax/Bcl-2 or Bax/Bcl-xL expression within CD8+ T cells of patients (42).