First, the median expression value of the given gene was used to define the high and low expressions, and then we split neuroblastoma patients into three groups: high-high expression of MTHDF2 and PAICS (HMTHFD2HPAICS); low-low expression of MTHDF2 and PAICS (LMTHFD2LPAICS), and high-low or low-high expression of MTHFD2 and PAICS (HMTHFD2LPAICS or LMTHFD2HPAICS). Here, MTHFD2 is linked to neuroblastoma.