(A) and (B) HeLa cells were treated with Tun (20 μg/ml, 6 h) in the absence or presence of PERK kinase inhibitor GSK2606414 (1 μM) with DMSO as the control. Total RNA and cell lysates were prepared, normalized for total protein and mRNA expression and immunoblotting of indicated proteins ASB7, CHOP and ATF4 for 6 h in HeLa cells and displayed as rations of the housekeeping gene (18s rRNA and β-actin). Data representative of 2 experiments. (C) HeLa cells were transfected with two different siRNAs targeting ASB7 and with scrambled (SC) siRNA control. After 2 days of transfection, cells were cultured with DTT (2 mM) and Tun (20 μg/ml) for 24 h. Cell viability was estimated by measuring MTT assay, expressing data as % of control untreated DMSO cells (mean ± SEM, n = 2). “ * ” denotes significance with respect to scramble and DMSO control. Error bars represent mean ± SEM. *** p≤0.001; **: p≤0.01; *: p≤0.05 calculated using one-way ANOVA.