Figure 1.

Sensitivity of LTC and GIC to single BA derivatives (AKBA, α-BA and β-BA) in acute viability and in clonogenic survival assays. LN-319 LTCs or T-269 GICs were exposed to increasing drug concentrations and metabolic activity was assessed by MTT assay in (A) acute viability or (B) clonogenic survival assays. (C) Cells were exposed to drugs (AKBA, 1.95, 19.50 or 195.00 µM; α-BA and β-BA, 2.2, 22.0 or 220.0 µM) for 2, 4, 8, 12, 24, 48 or 72 h and then subjected to MTT assays. Data are expressed as mean and SEM (n=2). LTC (left, filled symbols) or GIC (right, open symbols) were exposed to BA in a concentration-dependent manner, and metabolic activity was assessed by MTT assay in (D) acute viability or (E) clonogenicity assays. EC₅₀ values were calculated for each BA in every tested cell line. Representative results of two independent experiments are shown. The SEM was <15%. BA, boswellic acid; AKBA, acetyl-11-keto-β-boswellic acid; LTC, long-term cell line; GIC, glioma stem-like culture; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; EC₅₀, half maximal effective concentration; SEM, standard error of the mean.