As Gmnn inhibition selectively impaired the growth of several cancer cell lines under conditions where normal/non-cancer lines were not affected [10], we hypothesized that Gmnn inhibition might represent a therapeutic target inmedulloblastoma.Usingpubliclyavailabledata, we found that Gmnn expression is elevated in human medulloblastomas, relative to normal cerebellum (Figure 1A). The gene discussed is GMNN; the disease is cancer.