FIGURE 7.

Role of OCT1 in stimulation of BER enzyme expression due to BRCA1 overexpression. A and B, T47D cells were treated with control (CON)-siRNA or OCT1-siRNA (100 nm for 48 h) and then transfected overnight with either a wild-type (wt) BRCA1 expression vector (+) or empty pcDNA3 vector (−). The cells were post-incubated for 24 h to allow gene expression and then subjected to Western blotting to detect the indicated proteins. α-Actin was used as a control for loading and transfer. A shows a typical Western blot. B shows quantification of these experiments by densitometry. Values plotted are means ± S.E. of the fold-change (ratio of protein/actin normalized to control-siRNA and empty vector transfection value) based on three independent experiments. C and D, T47D cells were treated with control (CON)-siRNA or OCT1-siRNA and transfected with WTBRCA1 (+) or empty pcDNA3 vector (−), as above; and 30-μg aliquots of nuclear extracts were tested for incision of duplex oligonucleotides containing a TG lesion, using the corresponding wild-type oligonucleotide as a control. C shows a representative DNA gel and D shows quantification of three separate experiments. *, p < 0.05.