On the basis of these findings, we speculate that the EMT-inducer ZEB1 may support tumor metastasis in B16F10 melanoma-bearing mouse model by promoting tumor cell mobility and dissemination, and that antitumor immune responses induced by tumor vaccine B16F10/GPI-IL-21 might result in tumor cell apoptosis and inhibit tumor growth but do not block the EMT of B16F10 cells or metastasis in mice. The gene discussed is IL21; the disease is neoplasm.