Fig. 2.

DL-TBOA augments SN38-induced death in SN38-resistant cells, but protects oxaliplatin-resistant cells from oxaliplatin-induced death. Parental and drug-resistant HCT116 and LoVo cell lines seeded in 96-well dishes were exposed to SN38 (0.1 or 0.8 μM) or oxaliplatin (0.8 or 20 μM), alone or in combination with 70 or 350 μM DL-TBOA as indicated, for 48 h. Viability was assessed by MTT assay. a-b Parental HCT116 cells, (c) SN38 resistant HCT116 cells, (d) Oxaliplatin-resistant HCT116 cells, (e-f) Parental LoVo cells, (g) SN38 resistant LoVo cells, (h) Oxaliplatin-resistant LoVo cells. Data are means with S.E.M. error bars of 3 independent experiments. *) p < 0.05, **) p < 0.01, ***) p < 0.001 compared to the control group without drug or TBOA treatment; #) p < 0.05 compared to controls without TBOA treatment. One-way ANOVA followed by Dunnett post-test