Modulation of HIF-1α signaling in tumor antigen-specific CD8 T cells was achieved by nucleofecting activated TCRP1A CD8 T cells with ribonucleoproteins (RNP), consisting of the Cas9 protein in complex with guide RNA (gRNA) targeting HIF-1α or two major isoforms of PHD enzymes expressed by CD8 T cells: PHD2 and PHD3 (Fig. 1a). The gene discussed is CD8A; the disease is neoplasm.