MEK

Left: BRAFV600E A375 cells expressing pLKO or shMED12 vectors were cultured in the absence or presence of 2.5 μM PLX4032 or 0.5 μM AZD6244. The cells were fixed, stained, and photographed after 10 (untreated) or 28 days (treated). Right: A375 cells expressing pLKO or shMED12 vectors were grown in the absence or presence of 1 μM PLX4032 or 0.5 μM AZD6244 for 6 hr.

Phosphorylation of PPARg in epididymal white adipose tissue in ob/ob mice after treatment with MEK inhibitors. Gene expression in ob/ob epididymal white adipose tissue after treatment with vehicle or either of two MEK inhibitors, PD0325901 or GSK1120212 (n = 7, 7 and 8, respectively). Areas under the curve and gene expression were analysed by analysis of variance.

SMYD3 knockout augments the effects of the MEK1/2 inhibitor Trametinib (GSK1120212) in vivo. Representative serial HE staining and IHC for pERK1/2, a marker of Ras activity, and MUC5, a marker of PanIN lesions. All scale bars, 50 um.

 

Melanoma cell viability and in vivo growth by cyclindependent kinase 2/4 inhibition. Western blot analysis for c-Jun, phosphorylated-ERK1/2 (Thr202/Tyr204) (p-ERK1/2), and total ERK1/2 protein levels was done for human melanoma cell lines treated with the BRAFV600E inhibitor GDC-0879 (1 μM), or MEK inhibitors CI-1040 (1 μM), U0126 (1 μM), and PD98059 (10 μM) for 18 hours.

The inhibitor PD173074 (A) or PD184352 (B) was administered to one uterine horn of Hand2d/d mice on day 3 of pregnancy (n = 5). The other horn served as vehicle-treated control. Uterine horns were collected on the morning of day 4, and sections were subjected to IHC to detect p-FRS2, p-ERK1/2, and Ki-67. (C) IHC of pERa and Muc-1 in uterine sections of Hand2d/d mice treated with PD173074 or PD184352.

a-c, Inhibitors of BRAFV600E (PLX4032) and MEK1/2 (PD98059 or AZD6244) increase PGC1α and ID2 expression (a, b) and repress integrin expression and signalling (b, c). Cells were treated with indicated concentration of inhibitors for 6 h (a, b) or 24 h (c). d, e, PLX4032 increases the interaction between ID2 and TCF4 (d) and decreases the occupancy of TCF4 at the promoters of integrin genes (e). f–g, PGC1α and ID2 are partially required for PLX4032-mediated inhibition of invasion and metastasis. For in vitro assays (f), A375 cells were incubated with 1 μM PLX4032 for 10 h. Images represent one picture captured per membrane with the scale bar representing 200 μm. Values in a, b, e and f represent mean±s.d. of independent biological triplicates; *P<0.05 and **P<0.01 by Student's t-test  in a, b, e, f.

Western blot analysis showing HSP27 up-regulation on treatment of MKN-45 cells with the 2 indicated MEK1/2 kinase inhibitors (AS703026: 0.5 uM; PD98059: 10 uM) for the indicated time. Inset: effectiveness of the inhibitors in reducing Erk1/2 phosphorylation.

Retrograde NGF increased BDNF expression in sensory neurons, which was mediated by the MEK/ERK pathway. In two-compartmented DRG-nerve culture, NGF (50 ng/mL) was added to the chamber containing the sensory axonal terminals. The expression of BDNF was examined in the DRG neuronal soma located in another chamber. After 12 h of NGF treatment, the level of BDNF was increased in the sensory neuronal cell bodies by 3 fold (compare B to A) when compared to control (E). The role of the MEK/ERK pathway in retrograde NGF-triggered BDNF up-regulation was determined by pre-treatment of the ganglia with inhibitors U0126 (C), PD98059 (D) or BIX02188 (E). All inhibitors significantly reduced NGF-evoked BDNF up-regulation in the ganglia when compared to vehicle treatment (F). Results were from 4 independent experiments for each treatment. Bar=80 μm. *, p＜0.05 vs all groups.

(c) Fold induction of apoptotic cells after 3-day compound or vehicle (DMSO) treatment, as measured by annexin V positivity. Error bars indicate s.d.'s (n=4). **P<0.01, ***P<0.001, two-way ANOVA with Holm Sidak multiple comparisons correction.

iKras p53L/+ cells were treated with AZD8330 (50 nM), BKM120 (150 nM), or Rapamycin (20 nM) for 18 hr. As control, cells were cultured in the presence or absence of doxycycline for 24 hr, and cell lysates were blotted for phospho-Akt, phospho-Erk, phospho-S6, and Myc.

Cells seeded in 96-well plates (2,000-3,000 cells per well) were cultured in triplicate with or without graded concentrations of MEK1/2 plus/minus 100 μg/mL cetuximab, which were not renewed during the entire period of cell exposure. For each pair of columns, the height of the left columns represents the sum of the toxic effect of each agent and, therefore, the expected toxicity if their effects were additive when used in combination. The total height of the right columns represents the observed toxicity when the agents were used in combination. The difference between the heights of the paired columns reflects the magnitude of antagonism or synergism on cell toxicity between MEK1/2 inhibitors and cetuximab in NRAS^+/+ (left panels) and NRAS^Q61K/+ (right panels) cells. Results are shown as mean (columns) ± SD (error bars) from at least three experiments in which triplicate wells were analyzed.

After starved in serum-free medium for 24h, T47D cells incubated with the indicated concentrations of PD318088 for 3h,followed by 20-minute stimolation of 100ng/ml EGF.

(B) Cleaved PARP, Bax and Bcl2 protein expression was evaluated by immunoblotting of KRAS mutant cells lysates after 48 h of honokiol (10, 20, 40, and 60 μM) treatment. ∗∗P < 0.01 and ∗∗∗P < 0.001 for comparison between control group and honokiol-treated group.

RDEA119 (1 µM) or JTP-74057 (0.1 µM) abolished the effects of G1 on DAPK1 and NR2B phosphorylation.

Three types of selective inhibitors of MAPK signaling produce expected differential kinase inhibition and activation responses in HCT116 colorectal cancer cells. HCT116 cells were treated with 250 nM of GDC-0973, GDC-0623, SCH772984 or DMSO for 1, 4, or 24 h. In the washout samples, cells were drug treated for 24 h, then changed into fresh media and harvested after 0.5 or 2 h. Lysates were used for Western blots of total and phosphorylated MEK, ERK, and RSK; blotting for COX IV was used as the loading control.

Three types of selective inhibitors of MAPK signaling produce expected differential kinase inhibition and activation responses in HCT116 colorectal cancer cells. HCT116 cells were treated with 250nM of GDC-0973, GDC-0623, SCH772984 or DMSO for 1, 4, or 24 hours. In the washout samples, cells were drug treated for 24 hours, then changed into fresh media and harvested after 0.5 or 2 hours. Lysates were used for western blots of total and phosphorylated MEK, ERK and RSK; blotting for COX IV was used as the loading control.

Detection of the effects of letrozole and the MAPK pathway on the proliferation of GC-1 spg cells by BrdU. MAPK, mitogen-activated protein kinase; spg, spermatogonia; BrdU, bromodeoxyuridine