SMO and medulloblastoma: However, another study has proposed the role of cilia loss in the context of drug resistance to SMO inhibitors in vitro and in vivo, in which the loss of cilia in medulloblastoma cells was associated with mutations in OFD1, and a basal level of activated Hedgehog pathway sustained tumor growth [184], indicating that the role of cilia in promoting cell death resistance depends on the oncogenic context.