The quorum sensing com system regulates pneumococcal colonisation and invasive disease in a pseudo-stratified airway tissue model.

BACKGROUND: The effects of the com quorum sensing system during colonisation and invasion of Streptococcus pneumoniae (Spn) are poorly understood. METHODS: We developed an ex vivo model of differentiated human airway epithelial (HAE) cells with beating ciliae, mucus production and tight junctions to study Spn colonisation and translocation. HAE cells were inoculated with Spn wild-type TIGR4 (wtSpn) or its isogenic ΔcomC quorum sensing-deficient mutant. RESULTS: Colonisation density of ΔcomC mutant was lower after 6 h but higher at 19 h and 30 h compared to wtSpn. Translocation correlated inversely with colonisation density. Transepithelial electric resistance (TEER) decreased after pneumococcal inoculation and correlated with increased translocation. Confocal imaging illustrated prominent microcolony formation with wtSpn but disintegration of microcolony structures with ΔcomC mutant. ΔcomC mutant showed greater cytotoxicity than wtSpn, suggesting that cytotoxicity was likely not the mechanism leading to translocation. There was greater density- and time-dependent increase of inflammatory cytokines including NLRP3 inflammasome-related IL-18 after infection with ΔcomC compared with wtSpn. ComC inactivation was associated with increased pneumolysin expression. CONCLUSIONS: ComC system allows a higher organisational level of population structure resulting in microcolony formation, increased early colonisation and subsequent translocation. We propose that ComC inactivation unleashes a very different and possibly more virulent phenotype that merits further investigation.

Local tumor microbial signatures and response to checkpoint blockade in non-small cell lung cancer.

In cancer patients, the clinical response to checkpoint-based immunotherapy is associated with the composition and functional quality of the host microbiome. While the relevance of the gut microbiome for checkpoint immunotherapy outcome has been addressed intensively, data on the role of the local tumor microbiome are missing. Here, we set out to molecularly characterize the local non-small cell lung cancer microbiome using 16S rRNA gene amplicon sequencing of bronchoscopic tumor biopsies from patients treated with PD-1/PD-L1-targeted checkpoint inhibitors. Our analyses showed significant diversity of the tumor microbiome with high proportions of Firmicutes, Bacteroidetes and Proteobacteria. Correlations with clinical data revealed that high microbial diversity was associated with improved patient survival irrespective of radiology-based treatment response. Moreover, we found that the presence of Gammaproteobacteria correlated with low PD-L1 expression and poor response to checkpoint-based immunotherapy, translating into poor survival. Our study suggests novel microbiome-specific/derived biomarkers for checkpoint immunotherapy response prediction and prognosis in lung cancer. In a broader sense, our data draw attention to the local tumor microbial habitat as an important addition to the spatially separated microbiome of the gut compartment.

Status quo of ALK testing in lung cancer: results of an EQA scheme based on in-situ hybridization, immunohistochemistry, and RNA/DNA sequencing.

With this external quality assessment (EQA) scheme, we aim to investigate the diagnostic performance of the currently available methods for the detection of ALK alterations in non-small cell lung cancer on a national scale, namely, in situ hybridization (ISH), immunohistochemistry (IHC), and RNA/DNA sequencing (NGS). The EQA scheme cohort consisted of ten specimens, including four ALK positive and six ALK negative samples, which were thoroughly pretested using IHC, ISH, and RNA/DNA NGS. Unstained tumor sections were provided to the 57 participants, and the results were retrieved via an online questionnaire. ISH was used by 29, IHC by 38, and RNA/DNA sequencing by 19 participants. Twenty-eight institutions (97%) passed the ring trial using ISH, 33 (87%) by using IHC, and 18 (95%) by using NGS. The highest sensitivity and interrater agreement (Fleiss ' kappa) was observed for RNA/DNA sequencing (99%, 0.975), followed by ISH (94%, 0.898) and IHC (92%, 0.888). However, the proportion of samples that were not evaluable due to bad tissue quality was also higher for RNA/DNA sequencing (4%) compared with ISH (0.7%) and IHC (0.5%). While all three methods produced reliable results between the different institutions, the highest sensitivity and concordance were observed for RNA/DNA sequencing. These findings encourage the broad implementation of this method in routine diagnostic, although the application might be limited by technical capacity, economical restrictions, and tissue quality of formalin-fixed samples.

Establishment of Primary Transgenic Human Airway Epithelial Cell Cultures to Study Respiratory Virus-Host Interactions.

Primary human airway epithelial cell (hAEC) cultures represent a universal platform to propagate respiratory viruses and characterize their host interactions in authentic target cells. To further elucidate specific interactions between human respiratory viruses and important host factors in the airway epithelium, it is important to make hAEC cultures amenable to genetic modification. However, the short and finite lifespan of primary cells in cell culture creates a bottleneck for the genetic modification of these cultures. In the current study, we show that the incorporation of the Rho-associated protein kinase (ROCK) inhibitor (Y-27632) during cell propagation extends the life span of primary human cells in vitro and thereby facilitates the incorporation of lentivirus-based expression systems. Using fluorescent reporters for fluorescence-activated cell sorting (FACS)-based sorting, we generated homogenously fluorescent hAEC cultures that differentiate normally after lentiviral transduction. As a proof-of-principle, we demonstrate that host gene expression can be modulated post-differentiation via inducible short hairpin (sh)RNA-mediated knockdown. Importantly, functional characterization of these transgenic hAEC cultures with exogenous poly (I:C), as a proxy for virus infection, demonstrates that such modifications do not influence the host innate immune response. Moreover, the propagation kinetics of both human coronavirus 229E (HCoV-229E) and human respiratory syncytial virus (hRSV) were not affected. Combined, these results validate our newly established protocol for the genetic modification of hAEC cultures, thereby unlocking a unique potential for detailed molecular characterization of virus-host interactions in human respiratory epithelium.

CCL19-producing fibroblastic stromal cells restrain lung carcinoma growth by promoting local antitumor T-cell responses.

BACKGROUND: A particular characteristic of non-small cell lung cancer is the composition of the tumor microenvironment with a very high proportion of fibroblastic stromal cells (FSCs). OBJECTIVE: Lapses in our basic knowledge of fibroblast phenotype and function in the tumor microenvironment make it difficult to define whether FSC subsets exist that exhibit either tumor-promoting or tumor-suppressive properties. METHODS: We used gene expression profiling of lung versus tumor FSCs from patients with non-small cell lung cancer. Moreover, CCL19-expressing FSCs were studied in transgenic mouse models by using a lung cancer metastasis model. RESULTS: CCL19 mRNA expression in human tumor FSCs correlates with immune cell infiltration and intratumoral accumulation of CD8+ T cells. Mechanistic dissection in murine lung carcinoma models revealed that CCL19-expressing FSCs form perivascular niches to promote accumulation of CD8+ T cells in the tumor. Targeted ablation of CCL19-expressing tumor FSCs reduced immune cell recruitment and resulted in unleashed tumor growth. CONCLUSION: These data suggest that a distinct population of CCL19-producing FSCs fosters the development of an immune-stimulating intratumoral niche for immune cells to control cancer growth.

SUVmax and Tumour Location in PET-CT Predict Oncogene Status in Lung Cancer.

BACKGROUND: In non-small cell lung cancer, anaplastic lymphoma kinase gene rearrangement (ALK+) and epidermal growth factor receptor mutations (EGFR+) are targetable with tyrosine kinase inhibitors. PATIENTS AND METHODS: 27 patients with ALK+ tumours, who underwent positron emission tomography-computed tomography (PET-CT) prior to any treatment, were identified. 2 equally sized control groups based on consecutive patients with EGFR+ and EGFR/ALK wild-type (wt) were identified. The maximum standardized uptake value (SUVmax), tumour location (central vs. peripheral), as well as patient- and disease-specific characteristics were collected. RESULTS: Mutation status was significantly associated with SUVmax (p < 0.008). The median SUVmax of the primary tumour in the lung for ALK+ patients (SUVmax 13) was significantly higher compared to that of the EGFR+ (SUVmax 9.8, p = 0.010) and the EGFR/ALKwt group (SUVmax 9.6, p = 0.022). No difference was observed between the EGFR+ and the EGFR/ALKwt group (p = 0.961). Mutation status was also associated with primary tumour location (p = 0.001). There was a significantly lower rate of central tumours in the EGFR+ group when compared to ALK+ tumours (15%, p = 0.002). Among EGFR/ALKwt tumours, 41% were central compared to 63% of ALK+ tumours (p = 0.235). CONCLUSION: On initial PET-CT, ALK+ primary lung tumours showed a higher SUVmax and were more frequently centrally located while peripheral tumours were more likely to be EGFR+.

Vemurafenib-related sterile scrotal abscess in a patient with BRAFV600K-mutant advanced melanoma mimicking distant metastasis.

BACKGROUND: Vemurafenib is a selective BRAF-inhibitor that has been approved for the use in patients with advanced BRAF-mutant melanoma. Major adverse events include skin rash, photosensitivity, pruritus, cutaneous squamous-cell carcinoma or keratoacanthoma. OBSERVATION: We present the case of a patient experiencing extensive sterile abscess of the scrotum after nine months of treatment with vemurafenib for oligometastatic (liver) BRAF-mutant melanoma. The scrotal lesion mimicked distant metastasis in a first round of clinical and radiological examinations, but was identified as sterile abscess after surgical exploration and complete excision. The patient went on to receive hemihepatectomy for melanoma supposedly confined to the liver, and continues receiving vemurafenib. CONCLUSIONS: We describe a remarkable case of probably vemurafenib-related sterile abscess. This adverse event is of substantial clinical relevance, as it mimicks metastatic melanoma and requires careful diagnostic evaluation and proper treatment to allow a favorable patient outcome.

[Malignant hypoglycaemia]. / Maligne Hypoglykämie.

We describe the case of a 19-years old patient with seizure due to severe hypoglycaemia during general practitioner consultation. Because of hyperinsulinaemic hypoglycaemia and suspected liver metastasis a neuroendocrine hormone active tumor was suspected. After liver biopsy and CT scan a neuroendocrine pancreatic tumor could be diagnosed. Afterwards oncological therapy was induced.

EML4-ALK-Positive Pulmonary Adenocarcinoma with an Unusual Metastatic Pattern: A Case Report.

BACKGROUND: Non-small cell adenocarcinoma is a frequent tumour entity with a high mortality. Insight into molecular mechanisms has led to the development of promising therapeutic options, which improve the prognosis of affected patients. There are only a few reports on molecular tumour subtypes and clinical presentation of the disease. We present the case of a patient with anaplastic lymphoma kinase (ALK)-positive adenocarcinoma of the lung with an unusual metastatic pattern. CONCLUSION: The metastatic pattern of non-small cell lung cancer with ALK translocation may be different from other lung cancers. An uncommon clinical presentation may sensitize treating physicians to perform corresponding molecular testing in order to offer the best treatment options.

Epidermal growth factor receptor mutation in a patient with squamous cell carcinoma of the lung: who should be tested?

We report the case of a 64-year-old ex-smoker with metastatic poorly differentiated squamous cell carcinoma (SCC) of the lung and an epidermal growth factor receptor (EGFR) mutation in exon 21 (p.L858R) who achieved prolonged clinical benefit from treatment with an EGFR tyrosine kinase inhibitor (TKI). The initial diagnosis of SCC of the lung obtained by bronchoscopic biopsy was based on immunohistochemical staining only with positivity for cytokeratin (CK) 5/6 and p63 because morphological diagnosis was not possible. Patients with non-small cell lung cancer (NSCLC), not otherwise specified (NOS) favouring SCC are usually not tested for the presence of EGFR mutations, and therefore may not receive EGFR TKI therapy. A bronchoscopic rebiopsy showed small nests of undifferentiated tumour cells with weak immunoreactivity of some tumour cells for CK5/6, p63 and no positivity of some tumour cells for thyroid transcription factor-1. These findings suggested a mixed squamous/glandular immunophenotype that has been missed at the initial biopsy. Our clinical case illustrates the problem of tumour heterogeneity encountered in small bronchoscopic biopsies and the difficulties of evaluating the histological subtype in poorly differentiated carcinomas. Initial bronchoscopy should be performed by an experienced pulmonologist who attempts to obtain sufficient material from different areas of the tumour. In the era of targeted therapy, a remote smoking history in a patient with NOS favouring SCC should also lead to EGFR mutation testing to allow highly effective therapy to be offered to mutation-positive patients.

Anaplastic lymphoma kinase (ALK) gene rearrangement in non-small cell lung cancer (NSCLC): results of a multi-centre ALK-testing.

BACKGROUND: The reliable identification of non-small cell lung cancers (NSCLC) with chromosomal breaks in the gene of the anaplastic lymphoma kinase (ALK) is crucial for the induction of therapy with ALK-inhibitors. In order to ensure a reliable detection of ALK-breaks by means of fluorescence in situ hybridization (FISH) testing, round robin tests are essential. In preparation of a nation (German)-wide round robin test we initiated a pre-testing phase involving 8 experts in FISH-diagnostics to identify NSCLC cases (n = 10) with a pre-tested ALK-status. In addition, ALK immunohistochemistry (IHC) was performed to assess ALK protein expression. MATERIAL AND METHODS: Sections derived from a tissue microarray, each consisting of 3 cores from 10 NSCLC cases, were independently tested for ALK protein expression by IHC and genomic ALK-breaks by FISH involving 8 institutes of pathology. Based on a pre-screening, 5 cases were identified to be clearly ALK-break negative, whereas the remaining 5 cases were ALK-break positive including one case with low percentage (20%) of positive cells. The latter had been additionally tested by RT-PCR. RESULTS: The 5 unequivocal ALK-break negative NSCLC were almost consistently scored negative by means of FISH and IHC by all 8 experts. Interestingly, 4 of the 5 cases with pre-defined ALK-breaks revealed homogenous FISH results whereas IHC for the detection of ALK protein expression showed heterogeneous results. The remaining case (low number of ALK-break positive cells) was scored negative by 3 experts and positive by the other 5. RT-PCR revealed the expression of an EML4-ALK fusion gene variant 1. CONCLUSION: ALK-break negative NSCLC cases revealed concordant homogeneous results by means of FISH and IHC (score 0-1) by all 8 experts. Discordant FISH results were raised in one ALK-break positive case with a low number of affected tumor cells. The remaining 4 ALK-break positive cases revealed concordant FISH data whereas the ALK-IHC revealed very diverse results. The cases with concordant FISH results provide an excellent basis for round robin ALK-FISH testing. As long as standardized ALK-IHC protocols are missing, ALK protein expression cannot by regarded as the method of choice for identification of patients eligible for treatment with ALK inhibitors.

Efficient replication of the novel human betacoronavirus EMC on primary human epithelium highlights its zoonotic potential.

The recent emergence of a novel human coronavirus (HCoV-EMC) in the Middle East raised considerable concerns, as it is associated with severe acute pneumonia, renal failure, and fatal outcome and thus resembles the clinical presentation of severe acute respiratory syndrome (SARS) observed in 2002 and 2003. Like SARS-CoV, HCoV-EMC is of zoonotic origin and closely related to bat coronaviruses. The human airway epithelium (HAE) represents the entry point and primary target tissue for respiratory viruses and is highly relevant for assessing the zoonotic potential of emerging respiratory viruses, such as HCoV-EMC. Here, we show that pseudostratified HAE cultures derived from different donors are highly permissive to HCoV-EMC infection, and by using reverse transcription (RT)-PCR and RNAseq data, we experimentally determined the identity of seven HCoV-EMC subgenomic mRNAs. Although the HAE cells were readily responsive to type I and type III interferon (IFN), we observed neither a pronounced inflammatory cytokine nor any detectable IFN responses following HCoV-EMC, SARS-CoV, or HCoV-229E infection, suggesting that innate immune evasion mechanisms and putative IFN antagonists of HCoV-EMC are operational in the new host. Importantly, however, we demonstrate that both type I and type III IFN can efficiently reduce HCoV-EMC replication in HAE cultures, providing a possible treatment option in cases of suspected HCoV-EMC infection. IMPORTANCE A novel human coronavirus, HCoV-EMC, has recently been described to be associated with severe respiratory tract infection and fatalities, similar to severe acute respiratory syndrome (SARS) observed during the 2002-2003 epidemic. Closely related coronaviruses replicate in bats, suggesting that, like SARS-CoV, HCoV-EMC is of zoonotic origin. Since the animal reservoir and circumstances of zoonotic transmission are yet elusive, it is critically important to assess potential species barriers of HCoV-EMC infection. An important first barrier against invading respiratory pathogens is the epithelium, representing the entry point and primary target tissue of respiratory viruses. We show that human bronchial epithelia are highly susceptible to HCoV-EMC infection. Furthermore, HCoV-EMC, like other coronaviruses, evades innate immune recognition, reflected by the lack of interferon and minimal inflammatory cytokine expression following infection. Importantly, type I and type III interferon treatment can efficiently reduce HCoV-EMC replication in the human airway epithelium, providing a possible avenue for treatment of emerging virus infections.

Extrapulmonary small cell carcinoma: An indication for prophylactic cranial irradiation? A single center experience.

BACKGROUND: Information about extrapulmonary small cell carcinoma (EPSCC) is limited and the role of prophylactic cranial irradiation (PCI) is unknown. PATIENTS AND METHODS: Disease presentation and outcome of all EPSCC at our hospital between 1990 and 2009 were retrospectively analyzed. RESULTS: Of 30 EPSCC, the male:female ratio was 58%:42%; 83% had a performance status of 0-2. Median age was 71 years (32-80). Seventeen (57%) had limited stage (LS), 13 (43%) extensive stage (ES). The location of the primary tumor was gastrointestinal (n = 8), unknown (6), gynecological (6), urogenital (5), and ear nose throat (5). Four (13%) developed brain metastases (2 ES, 2 LS). In ES, first line chemotherapy (CT) was given in 85%, mostly platinum-etoposide (64%). Response rate was 90%. In LS, CT and radiotherapy (RT) ± resection resulted in persistent remissions in 67% of patients. Median survival was 16 months (1-107 months), 18 months (1-107 months), and 9 months (0.4-25 months) for LS + ES, LS, and ES, respectively. Weight loss ≥5 % and ECOG performance status 3 + 4 were associated with poorer survival (p < 0.001 and p < 0.01, respectively). CONCLUSION: The incidence of brain metastases was relatively low (13%). More studies are necessary, before routinely offering PCI to patients with EPSCC. Best survival outcomes in LS were achieved with multimodality treatment including CT and RT. Prognosis was poor in patients with ES.

Elevated cardiac troponin I in sepsis and septic shock: no evidence for thrombus associated myocardial necrosis.

BACKGROUND: Elevated cardiac troponin I (cTnI) is frequently observed in patients with severe sepsis and septic shock. However, the mechanisms underlying cTnI release in these patients are still unknown. To date no data regarding coagulation disturbances as a possible mechanism for cTnI release during sepsis are available. METHODOLOGY/PRINCIPAL FINDINGS: Consecutive patients with systemic inflammatory response syndrome (SIRS), sepsis or septic shock without evidence of an acute coronary syndrome were analyzed. Coagulation parameters (clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), alpha-angle) were assessed in native whole blood samples, and using specific activators to evaluate the extrinsic and intrinsic as well as the fibrin component of the coagulation pathway with the use of rotational thrombelastometry (ROTEM). Thirty-eight patients were included and 22 (58%) were cTnI-positive. Baseline characteristics between TnI-positive and -negative patients were similar. The CT, CFT, MCF and the alpha-angle were similar between the groups with trends towards shorter CT in the extrinsic and fibrin activation. CONCLUSIONS/SIGNIFICANCE: We found no differences in coagulation parameters analyzed with rotational thrombelastometry between cTnI-positive and -negative patients with SIRS, severe sepsis, and septic shock. These findings suggest that pathophysiological mechanisms other than thrombus-associated myocardial damage might play a major role, including reversible myocardial membrane leakage and/or cytokine mediated apoptosis in these patients.