Fig. 4: ATF6 silencing confirms that ATF6 sustains BRCA-1 expression and protects against DNA damage cancer cells subjected to ER stress.

ATF6 was silenced in RKO cells and after 24 h cells were treated or not with DPE (100 μM) for 48 h. A Cell viability was measured by a Trypan Blue exclusion assay; the histograms represent the mean ± S.D. of live cells as percent of scramble control (scr) cells. *p-value < 0.05. B Protein expression level of ATF6, γH2AX, and BRCA-1 was evaluated by western blot analysis. β-Actin was used as loading control. The histograms represent the densitometric analysis of the ratio of specific protein/β-Actin of three different experiments. Data are represented as the mean plus S.D. *p-value < 0.05. ATF6 was silenced in RKO cells and after 24 h cells were treated or not with Thapsigargin (Tg) (30 nM) for 48 h. C Cell viability was measured by a Trypan Blue exclusion assay; the histograms represent the mean ± S.D. of live cells as percent of scramble control (scr) cells. *p-value < 0.05. D Protein expression level of ATF6, γH2AX, and BRCA-1 was evaluated by western blot analysis. β-Actin was used as loading control. The histograms represent the densitometric analysis of the ratio of specific protein/β-Actin of three different experiments. Data are represented as the mean plus S.D. *p-value < 0.05.