Fig. 4

Neither inactivation of ERS nor induction of mild ERS/UPR significantly reduce CRC cell viability. a Inhibition of the ERS/UPR by a gradient of 4-PBA (1, 2.5, 5 and 10 mM) for 12 h, 24 h or 48 h dose not suppress the cellular viability significantly. Even, some CRC cells displays increased viability. n = 6. * P < 0.05. b Compared with DMSO, low dose of Tm (0.5, 1 and 2 µg/mL) increases GRP78 and activates IRE1α pathway of the UPR. n = 3. *** P < 0.001. Uncropped blots are provided in Supplementary information Fig. S12. c Except for the treatment of 2 µg/mL of Tm on RKO cells for 12 h, the cellular viability is generally not inhibited a lot when treated with low dose of Tm (0.5, 1 and 2 µg/mL). n = 6. * P < 0.05. Tm denotes Tunicamycin