Following IGF-I stimulation of a JCPyV LT expressing medulloblastoma cell line (BsB8) and a LT-negative medulloblastoma cell line (Bs-1a), a prolonged (>3 h after stimulation) phosphorylation of AKT was observed in the LT-positive cells, whereas a very transient (~30 min) phosphorylation of AKT was observed in the cells lacking LT [74]. This evidence concerns the gene IGF1 and medulloblastoma.