These include lower mutational rates, reduced lymphocyte cell infiltrates, low MHC expression and elevated numbers of immunosuppressive cellular infiltrates.45–47 Virotherapy enhances immune cell infiltration into the tumor and MHC upregulation and can change myeloid polarization, all of which can turn a ’cold’ tumor to ‘hot’.25 48 However, if these tumors have low mutational rates and no neoantigens, the immune cells may not generate ongoing antitumor activity after viral replication ceases. The gene discussed is HLA-C; the disease is neoplasm.