After the intratumoral injection of recombinant IFN-α protein (3 × 105 IU g−1), the concentration of IFN-α was 609±130 IU g−1 at day 1 and returned to the base line by day 3, which indicated the injected recombinant IFN-α protein was rapidly degraded in the tumour. This evidence concerns the gene IFNA2 and neoplasm.