The response of GBM to temozolomide (TMZ), clomipramine (CLM), and vincristine (VCR) when in co-culture with different ratios of astrocytes in 2D. (A,B) Proliferation of U-87 MG (A) and UP-007 (B) in mono- or co-culture with UP-010 when treated with TMZ (400 μM). (C,D) U-87 MG (C) and UP-007 (D) cell proliferation in a mono- or co-culture with astrocytes after treatment with CLM (20 μM). (E,F) Proliferation of U-87MG (E) and UP-007 (F) cells in co-culture with UP-010 when treated with VCR (2 μM). Co-cultures of GBM and astrocytes were established at ratios of 90:10, 80:20, and 50:50 of GBM to UP-010. Cell proliferation is expressed in relation to control of GBM cells growing in monoculture. Mean ± SEM (n = 3). * p < 0.05, ** p < 0.01 in comparison to monoculture of GBM.