MTHFR and glioblastoma: The recognized impact of rs1801133 (C677T) functional polymorphism impairment on the key regulatory enzyme (MTHFR) of folate metabolism gains increased relevance in the context of highly invasive and proliferative glioblastoma, especially if considered the tumor cells metabolic reprogramming as a key pillar of malignant transformation [42] [43, 44].