Han et al. (2011) reported that, when B16 melanoma cells were co-injected with MSCs pre-incubated with interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in syngeneic mice, xenografts were developed faster than those obtained from B16 cells alone whereas tumor incidence was increased in allogeneic recipients [45]. The gene discussed is TNF; the disease is neoplasm.