BACKGROUND We observed a syndrome of intermittent fevers, early-onset lacunar strokes and other neurovascular manifestations, livedoid rash, hepatosplenomegaly, and systemic vasculopathy in three unrelated patients. We suspected a genetic cause because the disorder presented in early childhood. METHODS We performed whole-exome sequencing in the initial three patients and their unaffected parents and candidate-gene sequencing in three patients with a similar phenotype, as well as two young siblings with polyarteritis nodosa and one patient with small-vessel vasculitis. Enzyme assays, immunoblotting, immunohistochemical testing, flow cytometry, and cytokine profiling were performed on samples from the patients. To study protein function, we used morpholino-mediated knockdowns in zebrafish and short hairpin RNA knockdowns in U937 cells cultured with human dermal endothelial cells. RESULTS All nine patients carried recessively inherited mutations in CECR1 (cat eye syndrome chromosome region, candidate 1), encoding adenosine deaminase 2 (ADA2), that were predicted to be deleterious; these mutations were rare or absent in healthy controls. Six patients were compound heterozygous for eight CECR1 mutations, whereas the three patients with polyarteritis nodosa or small-vessel vasculitis were homozygous for the p.Gly47Arg mutation. Patients had a marked reduction in the levels of ADA2 and ADA2-specific enzyme activity in the blood. Skin, liver, and brain biopsies revealed vasculopathic changes characterized by compromised endothelial integrity, endothelial cellular activation, and inflammation. Knockdown of a zebrafish ADA2 homologue caused intracranial hemorrhages and neutropenia — phenotypes that were prevented by coinjection with nonmutated (but not with mutated) human CECR1. Monocytes from patients induced damage in cocultured endothelial-cell layers. CONCLUSIONS Loss-of-function mutations in CECR1 were associated with a spectrum of vascular and inflammatory phenotypes, ranging from early-onset recurrent stroke to systemic vasculopathy or vasculitis. (Funded by the National Institutes of Health Intramural Research Programs and others.)

Checkpoint inhibitors are relatively inefficacious in head and neck cancers, despite an abundance of genetic alterations and a T cell-inflamed phenotype. One significant barrier to efficacy may be the recruitment of myeloid-derived suppressor cells (MDSC) into the tumor microenvironment. Here we demonstrate functional inhibition of MDSC with IPI-145, an inhibitor of PI3Kδ and PI3Kγ isoforms which enhances responses to PD-L1 blockade. Combination therapy induced CD8+ T lymphocyte-dependent primary tumor growth delay and prolonged survival only in T cell-inflamed tumor models of head and neck cancers. However, higher doses of IPI-145 reversed the observed enhancement of anti-PD-L1 efficacy due to off-target suppression of the activity f tumor-infiltrating T lymphocytes. Together, our results offer a preclinical proof of concept for the low dose use of isoform-specific PI3Kδ/γ inhibitors to suppress MDSC to enhance responses to immune checkpoint blockade.

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Food and Drug Administration Office of Orphan Product Development award, RO1 FD003005; NHLBI awards, PO1 HL73104 and Z01 HG000122; UCLA Clinical and Translational Science Institute awards, UL1RR033176 and UL1TR000124.

Wiskott-Aldrich syndrome protein (WASP) plays a key role in cytoskeletal rearrangement and transcriptional activation in T-cells. Recent evidence links WASP and related proteins to actin polymerization by the Arp2/3 complex. To study whether the role of WASP in actin polymerization is coupled to T-cell receptor (TCR)-mediated transcriptional activation, we made a series of WASP deletion mutants and tested them for actin colocalization, actin polymerization, and transcriptional activation of NFAT. A WASP mutant with a deletion in the C-terminal region (WASP⌬C) that is defective in actin polymerization potentiated NFAT transcription following TCR activation by anti-CD3 and anti-CD3/CD28 antibodies, but not by phorbol 12-myristate 13-acetate/ ionomycin. Furthermore, cotransfection of a dominantactive mutant (WASP-WH2-C) for Arp2/3 polymerization did not inhibit NFAT activation. Finally, by analyzing a series of WASP double-domain deletion mutants, we determined that the WASP homology-1 domain is responsible for NFAT transcriptional activation. Our results suggest that WASP activates transcription following TCR stimulation in a manner that is independent of its role in Arp2/3-directed actin polymerization.

Human papilloma viruses (HPV) are linked to an epidemic increase in oropharyngeal head and neck squamous cell carcinomas (HNSCC), which display viral inactivation of tumor suppressors TP53 and RB1 and rapid regional spread. However, the role of genomic alterations in enabling the modulation of pathways that promote the aggressive phenotype of these cancers is unclear. Recently, a subset of HPV HNSCC has been shown to harbor novel genetic defects or decreased expression of (). TRAF3 has been implicated as a negative regulator of alternative NF-κB pathway activation and activator of antiviral type I IFN response to other DNA viruses. How alterations affect pathogenesis of HPV HNSCC has not been extensively investigated. Here, we report that TRAF3-deficient HPV tumors and cell lines exhibit increased expression of alternative NF-κB pathway components and transcription factors NF-κB2/RELB. Overexpression of in HPV cell lines with decreased endogenous TRAF3 inhibited NF-κB2/RELB expression, nuclear localization, and NF-κB reporter activity, while increasing the expression of IFNA1 mRNA and protein and sensitizing cells to its growth inhibition. Overexpression of TRAF3 also enhanced TP53 and RB tumor suppressor proteins and decreased HPV E6 oncoprotein in HPV cells. Correspondingly, TRAF3 inhibited cell growth, colony formation, migration, and resistance to TNFα and cisplatin-induced cell death. Conversely, knockout enhanced colony formation and proliferation of an HPV HNSCC line expressing higher TRAF3 levels. Together, these findings support a functional role of as a tumor suppressor modulating established cancer hallmarks in HPV HNSCC. These findings report the functional role of TRAF3 as a tumor suppressor that modulates the malignant phenotype of HPV head and neck cancers. .

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The environment has become polluted with a variety of xenobiotics, including PCBs, as a result of the industrial development of useful halogenated compounds. While the PCBs may not exhibit the acute toxicity originally ascribed to them, they and their attendant byproducts remain as significant factors for adverse effects in the ecological food-chain. The use of microorganisms for bioremediation of PCBs is reviewed. This paper further details three new isolates obtained by conventional enrichment technics which show significant degradation capabilities for Aroclor 1242. These were identified by morphology, staining, and fatty acid analysis as Comamonas testosteroni, Rhodococcus rhodochrous, and a strain of Pseudomonasputida. These isolates demonstrated somewhat selective degradations of the congeners within Aroclor 1242; comprising total losses of 13.8, 19.1, and 24.6%, respectively. Each organism can attack dichloro-through tetrachlorobiphenyls. Analysis of chromatographic patterns from anaerobically digested Aroclor 1242 samples treated by these bacteria demonstrated decreases in di-through penta-substituted biphenyls. Each of these isolates, with discrete specificities, showed preferences for 'open' 2,3-sites, indicative of the action of 2,3-dioxygenase enzymes. The identification of many intermediates in the foregoing transformations was established by GC-MS analyses. Several variations in metabolic pathways, centering on the meta cleavage product 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) were suggested from these data. It is concluded that the described strains may be of future bioremediation use in processes which have an initial anaerobic dechlorination stage.