To investigate whether mc-oriP-IFNγ can mediate efficient expression of the IFNγ gene in EBV-positive NPC cells, the minicircle-IFNγ was compared with its parent plasmid p2ΦC31-IFNγ and the intermediate plasmid from which p2ΦC31-IFNγ was derived (pSP72). Here, IFNG is linked to nasopharyngeal carcinoma.