These considerations, together with our findings that knockdown of DJ-1 by shRNA in HMC-1 cells (S5 Fig) or by blockage of IL-6 in the mastocytosis model (Fig 6) reduces mast cell growth in culture or in vivo, respectively, suggest that while depletion of DJ-1 in ISM may result in cytostatic effects under oxidative stress, the IL-6-induced restoration of DJ-1 in more aggressive SM may prevent further oxidative damage, favoring mast cell survival and expansion. The gene discussed is IL6; the disease is mastocytosis.