BMP4 and glioblastoma: For this, we treated five patient-derived GBM cultures (see Section 4 with varying sensitivities to TMZ and BMP4 [4] either for four days with 60 ng BMP4/mL and then for seven days with 120 μM TMZ or exclusively for seven days with 120 μM TMZ or a combination (120 μM TMZ+ 60 ng BMP4/mL) of both agents.