👤 Holly Rosenzweig

Orientia tsutsugamushi is an obligately intracellular bacterium and the etiological agent of scrub typhus. The lung is a major target organ of infection, displaying type 1-skewed proinflammatory responses. Lung injury and acute respiratory distress syndrome are common complications of severe scrub typhus; yet, their underlying mechanisms remain unclear. In this study, we investigated whether the C-type lectin receptor (CLR) Mincle contributes to immune recognition and dysregulation. Following lethal infection in mice, we performed pulmonary differential expression analysis with NanoString. Of 671 genes examined, we found 312 significantly expressed genes at the terminal phase of disease. Mincle (Clec4e) was among the top 5 greatest up-regulated genes, accompanied with its signaling partners, type 1-skewing chemokines (Cxcr3, Ccr5, and their ligands), as well as Il27. To validate the role of Mincle in scrub typhus, we exposed murine bone marrow-derived macrophages (MΦ) to live or inactivated O. tsutsugamushi and analyzed a panel of CLRs and proinflammatory markers via qRT-PCR. We found that while heat-killed bacteria stimulated transitory Mincle expression, live bacteria generated a robust response in MΦ, which was validated by indirect immunofluorescence and western blot. Notably, infection had limited impact on other tested CLRs or TLRs. Sustained proinflammatory gene expression in MΦ (Cxcl9, Ccl2, Ccl5, Nos2, Il27) was induced by live, but not inactivated, bacteria; infected Mincle-/- MΦ significantly reduced proinflammatory responses compared with WT cells. Together, this study provides the first evidence for a selective expression of Mincle in sensing O. tsutsugamushi and suggests a potential role of Mincle- and IL-27-related pathways in host responses to severe infection. Additionally, it provides novel insight into innate immune recognition of this poorly studied bacterium. Show less

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal soft tissue neoplasm often linked to mTOR pathway activation via TSC2 mutation. We analyzed a series of 31 consecutive metastatic PEComa (mPEComa) cases using a combined DNA/RNA hybrid capture-based comprehensive genomic profiling (CGP) assay to assess the genomic landscape of mPEComa. Formalin-fixed, paraffin-embedded (FFPE) blocks or slides were obtained from tumors from 31 unique patients with mPEC-oma. DNA and RNA were extracted and CGP was performed on 405 genes using a targeted next-generation sequencing (NGS) assay in a CLIA-certified lab. All cases had locally advanced or metastatic disease, and 58% of patients were female with a median age of 50 years (range 8-76), and 17 and 14 specimens were from primary and metastatic sites, respectively. One hundred genomic alterations were identified in the cohort, with an average of 3.2 genomic alterations/case including alterations in TSC2 32.3% of cases (10), TSC1 9.6% (3), TFE3 16.1% (5, all fusions), and folliculin (FLCN) 6.4% (2), with all occurring in mutually exclusive fashion. Of TSC2 mutant cases, 70% had biallelic inactivation of this locus, as were 100% of TSC1 mutant cases. Two TSC1/2 wildtype cases harbored truncating mutations in FLCN, both of which were under LOH. Five TFE3 fusion cases were identified including the novel 5' fusion partner ZC3H4. We describe for the first time mPEComa cases with FLCN mutations under LOH, further characterizing dysregulation of the mTOR pathway as a unifying theme in mPEC-oma. Cumulatively, we demonstrate the feasibility and potential utility of segregating mPEComa by TSC, TFE3, and FLCN status via CGP in clinical care. Show less

Glioma susceptibility is inversely related to a history of allergies and atopy. Lung allergies are associated with 30% lower glioma susceptibility, compared to no lung allergies. Asthma and eczema also reduce the chance of glioma. However, the effect of allergy on glioma survival is not well characterized. Because of the allergy-glioma inverse relationship we examined the association of allergy with glioma survival in The Cancer Genome Atlas (TCGA). We evaluated the association between allergy and overall survival in TCGA Glioma (LGG) dataset. In order to have a sample of sufficient size to analyze, we classified as allergic any patient who answered yes to any of the manifestations of allergy that were queried. We analyzed data from 526 patients with glioma. History of allergy conferred a survival advantage on glioma patients, when stratified by tumor histologic grade (p = 0.049). Because allergy confers a favorable prognosis, we performed Cox regression. The effect of allergy on survival was significant (p = 0.025, HR 0.525, 95% CI 0.299-0.924), independent of the effect of chromosome 1p (p < 0.001, HR 93.4, 95% CI 16-546) and 19q (p = 0.801, HR 1.2, 95% CI 0.23-6.9) codeletion or TP53 mutation (p = 0.015, HR 2.7, 95% CI 1.2-5.9), unrelated to TERT expression (p = 0.365, HR 1.1, 95% CI 0.89-1.4) or ATRX mutation (p = 0.904, HR 1.04, 95% CI 0.51-2.14), independent of tumor grade (grade 2 versus grade 3, p = 0.004, HR 2.2, 95% CI 1.3-3.8), not independent of histology (oligodendroglioma and oligoastrocytoma, NOS versus astrocytoma, p = 0.08, HR 0.62, 95% CI 0.36-1.1). Diminished RNA expression of three loci, having reproducible genetic associations with allergic disease risk, are significantly associated with increased survival in glioma: FOSL2, APOBR, and NCF4. Diminished NCF4 copy number is significantly associated with reduced survival (D). Our finding of the improved prognosis that allergy confers on glioma increases the potential importance of understanding the allergy-glioma inverse association. If the mechanism could be more clearly elucidated, new, more effective treatments and preventive measures may be developed. Further studies are warranted. Show less