Cytotoxic effects of Tz on Tz-sensitive and -resistant breast cancer cells.

(A) Response to Tz with dose increase in SK-BR-3 cell line. The optimal dose of Tz was established. (B) Resistance to Tz in JIMT-1 cell line. Cells were treated with distilled water (control) or Tz for 72 h. Viable cells were counted in a Neubauer chamber. Relative survival rates are shown as percentages of untreated control cells. Bars shows mean ± standard deviation of triplicates. One-way ANOVA followed by post Scheffe test was used for statistical analysis to compare between groups. (*P < 0.05 significantly different from control; ^# P < 0.05 significantly different from 1μg/mL Tz treatment) Student’s t-test was used for statistical analysis to compare Tz treatment with control in JIMT-1 cell line.