[Clinical Management of Choanal Atresia]. / Klinisches Management der Choanalatresie.

Choanal atresia (CA) is a rare congenital anomaly of the nasal airway with an incidence of 1/5000 to 1/9000, which may occur unilateral (uCA) or bilateral (bCA). bCA manifests as an acute emergency immediately after birth by airway obstruction and paradoxical cyanosis, whereas uCA may present with a heterogeneous clinical picture in addition to unilateral nasal airway obstruction. Fiber endoscopic examination and cranial computed tomography are the gold standard in the diagnosis of CA. CA often occurs in association with congenital malformation syndromes, among which CHARGE syndrome stands out. Due to cardiopulmonary instability and difficult intubation conditions, syndromic CA patients should be considered as a separate risk group. After securing the airway, bCA must be treated surgically without delay, whereas correction of uCA should not be performed until after six months of age. Endoscopic techniques are the surgical standard in the treatment of CA. Different approaches can be distinguished: transnasal puncture of the atresia plate with subsequent extension medially and laterally, creation of a septal window with subsequent resection of the posterior vomer and atresia plate, and elevation of mucoperiosteal flaps with subsequent opening of the atresia plate. The transpalatal approach should only be employed in anatomically complex cases. The use of conventional choanal stents in the primary treatment of CA is increasingly rejected and should be reserved for high-risk constellations. Similarly, local application of mitomycin C should be avoided.

CD52 mRNA expression predicts prognosis and response to immune checkpoint blockade in melanoma.

The immune-modulating protein CD52 attenuates lymphocyte function and is associated with autoimmune disorders, for example, multiple sclerosis (MS). CD52 represents a therapeutic target in MS and chronic lymphocytic leukemia (CLL). Its expression has prognostic and predictive value in CLL and is prognostic in breast cancer. Its significance in melanoma is unclear. We analyzed CD52 mRNA expression data from tumor bulk tissues of N = 445 untreated melanoma patients from The Cancer Genome Atlas (TCGA) Research Network and of N = 121 melanoma patients undergoing anti-PD-1 immune checkpoint blockade (ICB) with regard to outcome (overall survival [OS], disease control [DC], and progression-free survival [PFS]), single-cell RNA-Seq data of N = 4645 cells from N = 19 melanoma tissues, and N = 15,457 cells from normal skin provided by N = 5 donors. Higher CD52 mRNA expression was associated with favorable OS (hazard ratio (HR) = 0.820, [95% CI 0.734-0.916], p < .001) in non-ICB-treated melanoma and with PFS (HR = 0.875, [95% CI 0.775-0.989], p = .033) and DC (p = .005) in ICB-treated melanoma. CD52 expression correlated significantly with distinct immune cell subsets and correlated negatively with immune checkpoint expression in T cells. Moreover, our results suggest CD52 expression by a certain type of tissue-resident macrophages. CD52 mRNA was expressed in a small subgroup (8%) of immune checkpoint coexpressing melanoma cells. CD52 expression is associated with features of ICB response in melanoma. Concomitant ICB and anti-CD52 treatment requires critical review.

CTLA4 DNA methylation is associated with CTLA-4 expression and predicts response to immunotherapy in head and neck squamous cell carcinoma.

BACKGROUND: The majority of patients with recurrent or metastasized head and neck squamous cell carcinoma (HNSCC) do not benefit from immune checkpoint blockade (ICB) while several patients experience severe and persistent immune-mediated side effects. Therefore, predictive biomarkers are urgently needed to allow for a personalized treatment. In this study, we investigated DNA methylation of the immune checkpoint gene CTLA4 with regard to its predictive value. METHODS: We analyzed CTLA4 promoter methylation in tumors of HNSCC patients (N = 29) treated with ICB at the University Medical Center Bonn with regard to response to ICB and progression-free survival. We further analyzed a second cohort (N = 138) of patients that did not receive ICB with regard to CTLA4 promoter methylation, CTLA-4 protein expression, and immune cell infiltrates. Finally, we tested inducibility of CTLA-4 protein expression in HNSCC cells using the DNA methyltransferase inhibitor decitabine. RESULTS: Lower CTLA4 promoter methylation correlated with response to ICB and prolonged progression-free survival. We could show that not only tumor infiltrating immune cells, but also HNSCC cells harbor cytoplasmic and nuclear CTLA-4 expression. CTLA4 promoter methylation inversely correlated with infiltrates of CD3+, CD4+, CD8+, and CD45+ immune cells. CTLA4 methylation did not correlate with protein expression in tumors, however, decitabine treatment led to decreased CTLA4 methylation and an induction of CTLA4 mRNA and CTLA-4 protein expression in HNSCC cell lines. CONCLUSIONS: Our results indicate that CTLA4 DNA hypomethylation is a predictive biomarker for response to ICB in HNSCC. Our study warrants further analyses of the predictive value of CTLA4 DNA methylation in clinical trials of anti-PD-1 and/or anti-CTLA-4 immunotherapy in HNSCC.

ICOS DNA methylation regulates melanoma cell-intrinsic ICOS expression, is associated with melanoma differentiation, prognosis, and predicts response to immune checkpoint blockade.

BACKGROUND: Inducible T cell costimulator ICOS is an emerging target in immuno-oncology. The aim of this study was to investigate the epigenetic regulation of ICOS in melanoma by DNA methylation. METHODS: We comprehensively investigate ICOS DNA methylation of specific CpG sites and expression pattern within the melanoma microenvironment with regard to immune correlates, differentiation, clinical outcomes, and immune checkpoint blockade (ICB) response. RESULTS: Our study revealed a sequence-contextual CpG methylation pattern consistent with an epigenetically regulated gene. We found a cell type-specific methylation pattern and locus-specific correlations and associations of CpG methylation with ICOS mRNA expression, immune infiltration, melanoma differentiation, prognosis, and response to ICB. High ICOS mRNA expression was identified as a surrogate for enriched immune cell infiltration and was associated with favorable overall survival (OS) in non-ICB-treated patients and predicted response and a prolonged progression-free survival (PFS) following ICB therapy initiation. ICOS hypomethylation, however, significantly correlated with poor OS in non-ICB patients but predicted higher response and prolonged PFS and OS in ICB-treated patients. Moreover, we observed cytoplasmic and sporadically nuclear tumor cell-intrinsic ICOS protein expression. Tumor cell-intrinsic ICOS protein and mRNA expression was inducible by pharmacological demethylation with decitabine. CONCLUSION: Our study identified ICOS DNA methylation and mRNA expression as promising prognostic and predictive biomarkers for immunotherapy in melanoma and points towards a hitherto undescribed role of ICOS in tumor cells.

In vivo analysis of noise dependent activation of white blood cells and microvascular dysfunction in mice.

This article contains supporting information on data collection for the research article entitled "Aircraft noise exposure drives the activation of white blood cells and induces microvascular dysfunction in mice" by Eckrich et al. We found that noise-induced stress triggered microvascular dysfunction via involvement of innate immune-derived reactive oxygen species. In this article, we present the instrumentation of mice with dorsal skinfold chambers for in vivo microscopic imaging of blood flow, interaction of leukocytes with the vascular wall (also by fluorescent labelling of blood cells) and vessel diameter. In addition, we explain the preparation of cerebral arterioles for measurement of vascular reactivity in vitro.•visualization of noise-dependent effects in dorsal skinfold chamber.•in vivo microscopy of noise-dependent activation of white blood cells.•analysis of noise-dependent microvascular dysfunction in dorsal skinfold chamber and cannulated cerebral arterioles.