Fig. 4.

Effects of elevated ARNT expression on radioresistance. a Hep3B cells were transfected either with the empty plasmid for control (ctrl.) or an appropriate ARNT expression vector (pARNT) and subjected to Western blot analysis. Actin levels were determined to ensure equal loading of samples. Protein masses are indicated on the right in kDa. b Clonogenic survival assays of irradiated Hep3B cells transfected as described in (a). n = 6, mean +/− SEM, unpaired t-test; (c) MCF-7 cells were transfected as indicated in (a) and subjected to Western Blotting. Actin levels were determined to ensure equal loading of samples. Protein masses are given in kDa. d Clonogenic survival assays of irradiated MCF-7 cells transfected as described in (a). n = 6, mean +/− SEM, unpaired t-test