IL9 and neoplasm: The MC38-luc tumor-bearing mice which were cured by the combination therapy of vvDD-IL-9 and anti-CTLA-4 antibody were re-challenged with a high dose of MC38 (1.0 × 106 per mouse) in the left flank and challenged with irrelevant tumor control B16 (5.0 × 105 per mouse) in the right flank.