CD8A and cancer: The induction of T-cell immunity following the vaccination of an orthotopic murine HNSCC model with a recombinant vaccinia virus expressing IL-2 induces tumor-specific CD8+ cytotoxic T cell (CTL) and CD4+ Th1-type helper T cells [51], which are targets of the cytocidal effects of galectin-1 secreted by cancer cells [52].