In this study, we introduced a new NDGA derivative, tetra-acetyl-O-nordihydroguaiaretic acid (A4N), which has more hydrophilic characteristics than M4N and can be dissolved in water more easily than M4N, and examined the effect of M4N and A4N treatment on the expression of SP1, MYC, HIF1A, and various proteins related to CSCs and epithelial–mesenchymal (EM) transition (which was strongly related to CSCs) [17,18], as well as on cell death induction in LN229 and U87MG GBM cells. Here, SP1 is linked to glioblastoma.