Figure 6: The MGST2-LTC4 pathway elicits ER stress-triggered cell death.
From: Leukotriene C4 is the major trigger of stress-induced oxidative DNA damage
Survival was determined by crystal violet staining and is relative to vehicle-treated cells. (a,b) Survival of WISH cells transfected with the indicated siRNA, treated with BfA (0.5 μg ml−1, 24 h). Bar, 100 μm. n=3, **P<0.02. (c) Immunoblot of MGST2 in extracts of WISH cells treated as in a. (d,e) Survival of WISH cells treated with BfA and pranlukast. Bar, 200 μm. n=3, ***P<0.001. (f,g) Survival of human HaCaT pre-keratinocytes treated with BfA (1.3 μg ml−1, 48 h) and BAY u9773 (80 nM). Bar, 100 μm. n=4, ***P<0.0001. (h,i) Survival of WISH cells treated with BfA (48 h) and BAY cysLT2. Bar, 500 μm. n=4, ***P<0.001. (j,k) Survival of HaCaT pre-keratinocytes treated with the proteasome inhibitor MG262 (0.05 μM) and zileuton. Bar, 50 μm. n=4, ***P<0.001. (l,m) Survival of B16 cells treated with Tm, thapsigargin (Tg) or BfA (1.3 μg ml−1) and the CysLTR1 antagonist MK571. Bar, 200 μm. n=4, ***P<0.001. (n) Immunoblot of the necrosis marker HMGB1 (top panel) in media of B16 cells treated with BfA (1.3 μg ml−1) and MK571 (MK). Ponceau S staining served as loading control. (o) Immunoblot of cleaved caspase-3 in extracts of WISH cells treated with Tm (2 μg ml−1, 48 h) and the indicated inhibitors. (p,q) Survival of B16 cells treated with LTC4. Bar, 200 μm. n=3, ***P<0.001. (r) Survival of B16 cells treated with LTC4 or LTD4. Bar, 200 μm. (s,t) Survival of HEK 293T cells stably transfected with Tet-inducible Mgst2 expression vector, treated with doxycycline (2 μg ml−1, 48 h). Bar, 200 μm. n=3, ***P<0.001. Immunoblots c,n and o are representatives of three replicates. Values in b,e,g,i,k,m,q and t represent the mean±s.d. Statistical significance was determined using one-way ANOVA.
