Fig. 4.

SBHA intensifies and prolongs ROS and Ca²⁺ generation caused by MDA-7/IL-24. (A) GBM6 cells were infected with empty vector or recombinant serotype 5 adenovirus to express MDA-7/IL-24 at a multiplicity of infection (moi) of 10. Twenty-four hours after infection, cells were treated with vehicle (DMSO; dimethylsulfoxide) or SBHA (3 μM). Cells were loaded with DCFH (dichlorofluorescin), and the levels of ROS under each condition determined 6, 12, and 24 hours after SBHA treatment (n = 3, ± S.E.M.). *P < 0.05 greater than Ad.5-mda-7 + vehicle. (B) GBM6 cells were infected with empty vector or recombinant serotype 5 adenovirus to express MDA-7/IL-24 at an moi of 10. Twenty-four hours after infection, cells were treated with vehicle (DMSO) or SBHA (3 μM). Cells were loaded with Fura-2, and the levels of free Ca²⁺ under each condition were determined 6, 12, and 24 hours after SBHA treatment (n = 3, ± S.E.M.). *P < 0.05 greater than Ad.5-mda-7 + vehicle. (C) GBM6 cells were transfected with an empty vector plasmid, a plasmid to express thioredoxin (TRX), or a plasmid to express calbindin and in parallel infected with empty vector or recombinant serotype 5 adenovirus to express MDA-7/IL-24 at an moi of 10. Twenty-four hours after infection, cells were treated with vehicle (DMSO) or SBHA (3 μM). Cells were isolated 48 hours later, and viability was determined by trypan blue exclusion (n = 3, ± S.E.M.). ^#P < 0.05 less than corresponding value in CMV transfected cells.