Figure 2

PXR expression reduced mRNA expression of p53 target gene p21 induced by doxorubicin and nutlin-3a. Human colon cancer HCT116 isogenic (p53^+/+; p53^−/−) cell lines stably transduced with lentiviral FLAG-tagged EV or FLAG-tagged hPXR (PXR) were treated with DMSO (0.1%) vehicle control, doxorubicin (1 μM) (Dox) for 4 h, or nutlin-3a (10 μM) (N3a) for 24 h. (a) qRT-PCR results for p21 (CDKN1A) mRNA expression as normalized to β-actin in HCT116 isogenic cells treated with DMSO (0.1%) vehicle control or doxorubicin (1 μM). (b) qRT-PCR results for PUMA (BBC3) mRNA expression as normalized to β-actin in HCT116 isogenic cells treated with DMSO (0.1%) vehicle control or doxorubicin (1 μM). (c) qRT-PCR results for CDKN1A mRNA expression as normalized to β-actin in HCT116 isogenic cells treated with DMSO (0.1%) vehicle control or nutlin-3a (10 μM). (d) qRT-PCR results for BBC3 mRNA expression as normalized to β-actin in HCT116 isogenic cells treated with DMSO (0.1%) vehicle control or nutlin-3a (10 μM). Data are shown as mRNA fold change (2^-ΔΔCT) relative to the mRNA level of the corresponding transcript in the control samples as indicated. Experiments were performed at least three times and all samples were analyzed in triplicate. Values are given as means±S.D.s (statistically significant if P<0.05, n=3). The comparison of experimental conditions was evaluated using one-way ANOVA and Tukey’s multiple comparisons test. The results of a representative experiment are shown.