Genetic Variation in MAP3K1 Associates with Ventilator-Free Days in Acute Respiratory Distress Syndrome.

Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) regulates numerous intracellular signaling pathways involved in inflammation and apoptosis. We hypothesized that genetic variation in MAP3K1 might be associated with outcomes in patients with acute respiratory distress syndrome (ARDS), and that these variants would alter MAP3K1-mediated changes in inflammation and transcriptional regulation. To test this hypothesis, we genotyped single-nucleotide polymorphisms covering linkage disequilibrium bins in MAP3K1 in 306 subjects with ARDS from the ARDSNet FACTT (Fluid and Catheter Treatment Trial) study, and tested for associations between MAP3K1 single-nucleotide polymorphisms and ventilator-free days (VFDs) and mortality. We then validated these associations in a separate cohort of 241 patients with ARDS from Harborview Medical Center (Seattle, WA). We found the variant allele of rs832582 (MAP3K1906Val) was significantly associated with decreased VFDs using multivariate linear regression (-6.1 d, false discovery rate = 0.06) in the FACTT cohort. In the Harborview Medical Center cohort, subjects homozygous for MAP3K1906Val also had decreased VFDs (-15.1 d, false discovery rate < 0.01), and increased 28-day mortality (all subjects homozygous for the rare allele died). In whole blood stimulated with various innate immune agonists ex vivo, MAP3K1906Val was associated with increased IL-1ß, IL-6, IL-8, monocyte chemoattractant protein 1, and TNF-α production. Transcriptome analysis of whole blood stimulated with Toll-like receptor 4 agonist ex vivo demonstrated enrichment of inflammatory gene sets in subjects homozygous for MAP3K1906Val. Our findings show a robust association between the variant allele of rs832582 (MAP3K1906Val) and decreased VFDs in patients with ARDS and suggest that this variant may predispose individuals to a greater inflammatory response.

Induction of copper/zinc-superoxide dismutase by CCL5/CCR5 activation causes tumour necrosis factor-alpha and reactive oxygen species production in macrophages.

Using two-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis, we found that copper/zinc superoxide dismutase (Cu/Zn-SOD, SOD-1) was induced in constructed CCR5 stably transfected HEK 293 cells, but not in mock cells, treated with CCL5. CCL5-induced SOD-1 expression was also confirmed in HEK 293-CCR5 cells and CCR5-positive granulocyte-macrophage colony-stimulating factor-induced human macrophages and murine macrophage RAW264.7 cells. CCL5 and CCR5 interaction induced SOD-1 expression mainly via MEK-ERK activation. In addition, we provided evidence that upregulation of SOD-1 by CCL5/CCR5 activation occurred in parallel with the increased release of tumour necrosis factor-alpha and nitric oxide and production of intracellular reactive oxygen species as well as enhanced nuclear factor-kappaB transcriptional activity in CCR5-positive RAW264.7 cells. Conversely, the MEK1/2 inhibitor PD98059 significantly inhibited SOD-1 expression with the decrease of these biological responses. More importantly, inhibition of SOD-1 activity by disulfiram also strongly inhibited the CCL5-induced biological effects. These data suggest that SOD-1 mediates CCR5 activation by CCL5 and that pharmacological modulation of SOD-1 may be beneficial to CCR5-associated diseases.

Genetic Variants in Immune-Related Pathways and Breast Cancer Risk in African American Women in the AMBER Consortium.

Background: Constitutional immunity shaped by exposure to endemic infectious diseases and parasitic worms in Sub-Saharan Africa may play a role in the etiology of breast cancer among African American (AA) women.Methods: A total of 149,514 gene variants in 433 genes across 45 immune pathways were analyzed in the AMBER consortium among 3,663 breast cancer cases and 4,687 controls. Gene-based pathway analyses were conducted using the adaptive rank truncated product statistic for overall breast cancer risk, and risk by estrogen receptor (ER) status. Unconditional logistic regression analysis was used to estimate ORs and 95% confidence intervals (CIs) for single variants.Results: The top pathways were Interleukin binding (P = 0.01), Biocarta TNFR2 (P = 0.005), and positive regulation of cytokine production (P = 0.024) for overall, ER+, and ER- cancers, respectively. The most significant gene was IL2RB (P = 0.001) for overall cancer, with rs228952 being the top variant identified (OR = 0.85; 95% CI, 0.79-0.92). Only BCL3 contained a significant variant for ER+ breast cancer. Variants in IL2RB, TLR6, IL8, PRKDC, and MAP3K1 were associated with ER- disease. The only genes showing heterogeneity between ER- and ER+ cancers were TRAF1, MAP3K1, and MAPK3 (P ≤ 0.02). We also noted genes associated with autoimmune and atopic disorders.Conclusions: Findings from this study suggest that genetic variants in immune pathways are relevant to breast cancer susceptibility among AA women, both for ER+ and ER- breast cancers.Impact: Results from this study extend our understanding of how inherited genetic variation in immune pathways is relevant to breast cancer susceptibility. Cancer Epidemiol Biomarkers Prev; 27(3); 321-30. ©2018 AACR.

Systemic Therapy Options for Patients With Unresectable Melanoma.

There has been a therapeutic revolution in the treatment of metastatic melanoma over the past decade. Patients presenting with inoperable disease have several therapeutic options, which can include both targeted and immune therapy. Immune checkpoint inhibitors have demonstrated an improvement in overall survival and led to some durable responses. However, toxicity, especially in combination regimens, can be severe. Adverse events should be anticipated, diagnosed as early as possible, monitored, and managed. Combination BRAF and MEK inhibition has also been shown to improve overall survival in patients with V600E-mutated melanoma. Responses to therapy are often rapid, and treatment is not associated with immune-related adverse events. Current trials are under way to determine which option is optimal as frontline therapy for patients with V600E melanoma. In patients with progressive disease despite standard therapies, clinical trials are recommended. There are several promising agents in development.

Development of an enzyme-linked immunosorbent assay (ELISA) for the specific detection of MEKK1 expression in cells.

INTRODUCTION: MEKK1 is a 196-kDa serine-threonine kinase activated in response to a variety of stimuli, including EGF, lysophosphatidic acid, osmotic stress, UV light, and microtubule toxins. However, there are few reports about the expression level of MEKK1 in cancers. METHODS: In this report, a direct competitive ELISA to quantify total MEKK1 in cell lines was developed. RESULTS: The procedure showed a high sensitivity (detection limit: 0.17 ng/ml), good precision (coefficient of variation

MEKK1/MEKK4 are responsible for TRAIL-induced JNK/p38 phosphorylation.

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been shown to activate mitogen-activated protein kinases (MAPKs) depending on caspase and mammalian sterile 20-like kinase 1 activations. However, the upstream molecule of MAPKs has not yet been identified. The mitogen-activated protein kinase kinase 1 (MEKK1) and the apoptosis signal-regulating kinase 1 (ASK1) are considered to be possible candidates for the action of MAPKKKs induced by TRAIL and the possibility of reactive oxygen species involvement has also been investigated. We found that MEKK1/MEKK4 as opposed to ASK1, are responsible for TRAIL-induced c-Jun NH2-terminal kinase (JNK) or p38 activation, and that their catalytic activity is repressed by the caspase-8 inhibitor, suggesting that the caspase-8 activation induced by TRAIL is indispensible for MEKK activation. The 14-3-3 θ was also shown to interact with and to dissociate from MEKK1 by TRAIL treatment, thus implicating the 14-3-3 protein as a negative regulator of MEKK1 activation. Taken together, we show herein that the upstream molecule of the TRAIL-induced MAPK activation is MEKK, as opposed to ASK1, via the mediation of its signal through JNK/p38 in a caspase-8-dependent manner.

The MAPKKK Mekk1 regulates the expression of Turandot stress genes in response to septic injury in Drosophila.

Septic injury triggers a rapid and widespread response in Drosophila adults that involves the up-regulation of many genes required to combat infection and for wound healing. Genome-wide expression profiling has already demonstrated that this response is controlled by signaling through the Toll, Imd, JAK-STAT and JNK pathways. Using oligonucleotide microarrays, we now demonstrate that the MAPKKK Mekk1 regulates a small subset of genes induced by septic injury including Turandot (Tot) stress genes. Our analysis indicates that Tot genes show a complex regulation pattern including signals from both the JAK-STAT and Imd pathways and Mekk1. Interestingly, Mekk1 flies are resistant to microbial infection but susceptible to paraquat, an inducer of oxidative stress. These results point to a role of Mekk1 in the protection against tissue damage and/or protein degradation and indicate complex interactions between stress and immune pathways in Drosophila.