JAG1 and glioblastoma: Treatment with 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) had no effect on Notch-2, Notch-4, or Jagged-1 protein expression in a cell model of glioblastoma, or on Notch-1 or Jagged-1 in keratinocytes [78,79].