Several mechanisms by which radiation has shown to modulate TME have been identified, including the induction of immunogenic cell death facilitating tumor-neoantigen presentation by antigen presenting cells, or “epitope spreading”, resulting in improved T-cell priming and activation, enhancement of T-cell infiltration through a release of T-cell-attractive chemokines, and/or an upregulation of surface receptors such as MHC-I and Fas that increase vulnerability of cancer cells to cytotoxic CD8 + T-cell attack30–33. The gene discussed is CD8A; the disease is cancer.