The impact of disparate isolation methods for extracellular vesicles on downstream RNA profiling

Despite an enormous interest in the role of extracellular vesicles, including exosomes, in cancer and their use as biomarkers for diagnosis, prognosis, drug response and recurrence, there is no consensus on dependable isolation protocols. We provide a comparative evaluation of 4 exosome isolation protocols for their usability, yield and purity, and their impact on downstream omics approaches for biomarker discovery. OptiPrep density gradient centrifugation outperforms ultracentrifugation and ExoQuick and Total Exosome Isolation precipitation in terms of purity, as illustrated by the highest number of CD63-positive nanovesicles, the highest enrichment in exosomal marker proteins and a lack of contaminating proteins such as extracellular Argonaute-2 complexes. The purest exosome fractions reveal a unique mRNA profile enriched for translation, ribosome, mitochondrion and nuclear lumen function. Our results demonstrate that implementation of high purification techniques is a prerequisite to obtain reliable omics data and identify exosome-specific functions and biomarkers.

Specific migratory dendritic cells rapidly transport antigen from the airways to the thoracic lymph nodes

Antigen transport from the airway mucosa to the thoracic lymph nodes (TLNs) was studied in vivo by intratracheal instillation of fluorescein isothiocyanate (FITC)-conjugated macromolecules. After instillation, FITC(+) cells with stellate morphology were found deep in the TLN T cell area. Using flow cytometry, an FITC signal was exclusively detected in CD11c(med-hi)/major histocompatibility complex class II (MHCII)(hi) cells, representing migratory airway-derived lymph node dendritic cells (AW-LNDCs). No FITC signal accumulated in lymphocytes and in a CD11c(hi)MHCII(med) DC group containing a CD8 alpha(hi) subset (non-airway-derived [NAW]-LNDCs). Sorted AW-LNDCs showed long MHCII(bright) cytoplasmic processes and intracytoplasmatic FITC(+) granules. The fraction of FITC(+) AW-LNDCs peaked after 24 h and had reached baseline by day 7. AW-LNDCs were depleted by 7 d of ganciclovir treatment in thymidine kinase transgenic mice, resulting in a strong reduction of FITC-macromolecule transport into the TLNs. Compared with intrapulmonary DCs, AW-LNDCs had a mature phenotype and upregulated levels of MHCII, B7-2, CD40, and intracellular adhesion molecule (ICAM)-1. In addition, sorted AW-LNDCs from FITC-ovalbumin (OVA)-instilled animals strongly presented OVA to OVA-TCR transgenic T cells. These results validate the unique sentinel role of airway DCs, picking up antigen in the airways and delivering it in an immunogenic form to the T cells in the TLNs.

The 5q-anomaly

A deletion of the long arm of chromosome #5 (5q-) occurs nonrandomly in human malignancies. As a rule, the deletion is interstitial; the distal breakpoint by conventional techniques is usually in band q32, the proximal breakpoints in q12 or q14. Variant breakpoints occur in less than 10% of all cases. As the sole anomaly, 5q- is characteristically found in refractory anemia with or without excess of blasts. It can occur as the sole anomaly in de novo or secondary acute nonlymphocytic leukemia, but is usually accompanied in those disorders by other chromosome changes that are also nonrandomly distributed. In addition, it can be found in lymphoproliferative disorders, and occasionally, also in solid tumors. The 5q- myelodysplastic syndrome typically occurs in older age groups, particularly in females. Characteristic features are macrocytic anemia, normal or elevated platelets in the presence of megakaryocytic anomalies, and a mild clinical course. In cases with 5q- only, transformation into ANLL occurs rarely. Additional chromosome anomalies and male sex are prognostically unfavorable signs. Sex ratio is also at the disadvantage of females in de novo 5q- ANLL, and the latter disorder can occur without being preceded by a myelodysplastic phase. A myelodysplastic phase usually precedes 5q- secondary leukemia, in males as well as in females, and additional chromosome anomalies, especially of chromosome #7, are almost invariably present in those cases. We conclude that 5q- is the most frequently occurring single chromosome anomaly in secondary leukemia. Furthermore, the resemblance between de novo and secondary 5q- MDS and ANLL is striking; clinically, as well as cytogenetically, they are indistinguishable, suggesting that all de novo cases may be due to environmental (chemical) carcinogens. Response to treatment and prognosis are very poor with current therapeutic regimens in de novo as well as in secondary 5q- ANLL. Morphologically, these ANLLs fall into all FAB categories. There is considerable evidence to show that the 5q- anomaly occurs in a myeloid precursor stem cell. The occasional occurrence in lymphoid malignancies, of B cell as well as T cell type, suggests that, as in Ph-positive disorders, a common progenitor stem cell may be affected in 5q- also. The 5q- lymphoid malignancies, however, are much more rare; it is not clear at the present time whether or not a 5q- counterpart of Ph-positive ALL exists, and mixed lymphoid-myeloid 5q- disorders have not yet been documented.(ABSTRACT TRUNCATED AT 400 WORDS)

Time course of cigarette smoke-induced pulmonary inflammation in mice

Inflammation of the airways and lung parenchyma plays a major role in the pathogenesis of chronic obstructive pulmonary disease. In the present study a murine model of tobacco smoke-induced emphysema was used to investigate the time course of airway and pulmonary inflammatory response, with a special emphasis on pulmonary dendritic cell (DC) populations. Groups of mice were exposed to either cigarette smoke or to control air for up to 24 weeks. In response to cigarette smoke, inflammatory cells (i.e. neutrophils, macrophages and lymphocytes) progressively accumulated both in the airways and lung parenchyma of mice. Furthermore, a clear infiltration of DCs was observed in airways (10-fold increase) and lung parenchyma (1.5-fold increase) of cigarette-exposed mice at 24 weeks. Flow cytometric analysis of bronchoalveolar lavage (BAL) DCs of smoke-exposed mice showed upregulation of major histocompatability complex II molecules and costimulatory molecules CD40 and CD86, compared with BAL DCs of air-exposed mice. Morphometric analysis of lung histology demonstrated a significant increase in mean linear intercept and alveolar wall destruction after 24 weeks of smoke exposure. In conclusion, the time course of the changes in inflammatory and dendritic cells in both bronchoalveolar lavage and the pulmonary compartment of cigarette smoke-exposed mice was carefully characterised.

Genes associated with common variable immunodeficiency: one diagnosis to rule them all?

Common variable immunodeficiency (CVID) is a primary antibody deficiency characterised by hypogammaglobulinaemia, impaired production of specific antibodies after immunisation and increased susceptibility to infections. CVID shows a considerable phenotypical and genetic heterogeneity. In contrast to many other primary immunodeficiencies, monogenic forms count for only 2-10% of patients with CVID. Genes that have been implicated in monogenic CVID include ICOS, TNFRSF13B (TACI), TNFRSF13C (BAFF-R), TNFSF12 (TWEAK), CD19, CD81, CR2 (CD21), MS4A1 (CD20), TNFRSF7 (CD27), IL21, IL21R, LRBA, CTLA4, PRKCD, PLCG2, NFKB1, NFKB2, PIK3CD, PIK3R1, VAV1, RAC2, BLK, IKZF1 (IKAROS) and IRF2BP2 With the increasing number of disease genes identified in CVID, it has become clear that CVID is an umbrella diagnosis and that many of these genetic defects cause distinct disease entities. Moreover, there is accumulating evidence that at least a subgroup of patients with CVID has a complex rather than a monogenic inheritance. This review aims to discuss current knowledge regarding the molecular genetic basis of CVID with an emphasis on the relationship with the clinical and immunological phenotype.

Accurate and simple discrimination of mouse pulmonary dendritic cell and macrophage populations by flow cytometry: methodology and new insights

BACKGROUND

The need to accurately discriminate dendritic cells (DCs) and macrophages (Mphs) in mouse lungs is critical given important biological differences. However, a validated flow cytometry-based method is still lacking, resulting in much confusion between both cell types.

METHODS

Single-cell suspensions freshly obtained from collagenase-digested lung tissue were stained with a CD11c-specific monoclonal antibody, detected using a PE-Cy5 or APC-conjugated secondary reagent. Cellular immunophenotype was simultaneously explored using a panel of PE-conjugated markers. The FL1 or FITC-detection channel was reserved for the assessment of autofluorescence.

RESULTS

CD11c-bright cells were heterogeneous and displayed a bimodal distribution with regard to autofluorescence (AF). CD11c+/low-AF cells were lineage-negative and showed features compatible with myeloid DCs. This was confirmed by morphology, potent T-cell stimulatory function in a mixed-leukocyte reaction, surface expression of MHCII and costimulatory molecules, and further immunophenotypical criteria, including the expression of Mac-1 and absence of CD8alpha. In contrast, CD11c+/high-AF cells displayed the features of pulmonary Mphs, including typical Mph morphology, very weak induction of T-cell proliferation, low to absent expression of MHCII and costimulatory molecules, and very low levels of Mac-1 as well as F4/80. We also show that only CD11c+/high-AF cells strongly expressed the macrophage marker MOMA-2, while interestingly Mac-3 was expressed at high levels by CD11c+/high-AF and low-AF alike.

CONCLUSIONS

This study shows that the combination of CD11c-expression and autofluorescence is necessary and sufficient to accurately separate DCs from macrophage subpopulations in mouse lungs.

Identification and Characterization of Human Pulmonary Dendritic Cells

Dendritic cells (DC) are specialized antigen-presenting cells, linking innate and adaptive immune responses, and thus play an important role in immunologically mediated diseases, including pulmonary diseases such as asthma and respiratory viral infections. Although much is known about the characteristics of lung DC in animal models, very few data concerning human lung DC are available. The goal of our study was to identify and characterize dendritic cells in human lung by preparing single-cell suspensions from surgical resection specimens and subsequent labeling with the recently developed blood dendritic cell antigen (BDCA) markers. A straightforward isolation procedure was developed to avoid phenotypical and functional changes induced by extensive purification methods. In this way, human lung DC were directly identified without the need for an additional adherence step for further purification. For the first time, we demonstrate the presence of three previously unidentified DC subsets in human lung digests: myeloid DC type 1 (BDCA1+/HLA-DR+), myeloid DC type 2 (BDCA3+/HLA-DR+), and plasmacytoid DC (BDCA2+/CD123+). The presence of CD1a+ DC in the human lung was confirmed. The identification and characterization of different human pulmonary DC subtypes is of great importance for the future development of DC-based immunotherapies.

Pulmonary dendritic cells

Dendritic cells (DCs) are leukocytes that are emerging as chief orchestrators of immune responses. The crucial task of DCs is the continuous surveillance of antigen-exposed sites throughout the body, and their unique responsibility is to decide whether to present sampled antigen in an immunogenic or tolerogenic way. Any misstep can either lead to a flawed immune defense or to allergy, even autoimmunity. It comes as no surprise that the lungs become increasingly the subject of DC-related investigations, as they represent a vast interface between the body and the outer world. This constitutes an enormous challenge for the immune system: "firing up" immune responses inappropriately could have devastating results for the fragile gas exchange structures. Evidence accumulates that DCs play a pivotal role in maintaining the delicate balance between tolerance and active immune response in our respiratory system. The exponentially growing body of DC-related publications is a big challenge. This article aims to provide researchers and clinicians with an up-to-date view on DC biology and its relevance to pulmonary medicine. A developing trend in the field of DCs is the shift from fundamental immunologic research toward exciting clinical insights and applications. For the pulmonary clinician, this heralds the dawn of promising therapies in various domains such as infections, allergy, and cancer.

Treatment of extensive-stage small cell lung carcinoma: current status and future prospects

Small cell lung cancer (SCLC) is an aggressive lung tumour strongly associated with cigarette smoking, with patients often presenting with metastatic disease at the time of diagnosis. Although SCLC is very chemoradiosensitive and high response rates are obtained with treatment, relapse rates are high and the prognosis remains very poor. In limited-stage SCLC, the overall survival rate has been significantly improved by adding dose-hyperfractionated thoracic radiotherapy and prophylactic cranial irradiation to systemic chemotherapy. In contrast, little progress has been made in the treatment of extensive-stage SCLC (ES-SCLC), apart from the recently documented survival gain by the addition of prophylactic cranial irradiation. First-line therapy in ES-SCLC currently consists of chemotherapy, combining a platinum drug with either etoposide or irinotecan as a possible alternative. New treatments are needed in order to improve the prognosis of ES-SCLC, as median survival with current standard treatment is still only 9-10 months from diagnosis. The present review focuses on the management of ES-SCLC, with special attention to the development of new treatment options.

Vaccine Strategies to Improve Anti-cancer Cellular Immune Responses

More than many other fields in medicine, cancer vaccine development has been plagued by a wide gap between the massive amounts of highly encouraging preclinical data on one hand, and the disappointing clinical results on the other. It is clear now that traditional approaches from the infectious diseases' vaccine field cannot be borrowed as such to treat cancer. This review highlights some of the strategies developed to improve vaccine formulations for oncology, including research into more powerful or “smarter” adjuvants to elicit anti-tumoral cellular immune responses. As an illustration of the difficulties in translating smart preclinical strategies into real benefit for the cancer patient, the difficult road of vaccine development in lung cancer is given as example. Finally, an outline is provided of the combinatorial strategies that leverage the increasing knowledge on tumor-associated immune suppressive networks. Indeed, combining with drugs that target the dominant immunosuppressive pathway in a given tumor promises to unlock the true power of cancer vaccines and potentially offer long-term protection from disease relapse.

Matrix metalloproteinase-9 deficiency impairs cellular infiltration and bronchial hyperresponsiveness during allergen-induced airway inflammation

We investigated the specific role of matrix metalloproteinase (MMP)-9 in allergic asthma using a murine model of allergen-induced airway inflammation and airway hyperresponsiveness in MMP-9(-/-) mice and their corresponding wild-type (WT) littermates. After a single intraperitoneal sensitization to ovalbumin, the mice were exposed daily either to ovalbumin (1%) or phosphate-buffered saline aerosols from days 14 to 21. Significantly less peribronchial mononuclear cell infiltration of the airways and less lymphocytes in the bronchoalveolar lavage fluid were detected in challenged MMP-9(-/-) as compared to WT mice. In contrast, comparable numbers of bronchoalveolar lavage fluid eosinophils were observed in both genotypes. After allergen exposure, the WT mice developed a significant airway hyperresponsiveness to carbachol whereas the MMP-9(-/-) mice failed to do so. Allergen exposure induced an increase of MMP-9-related gelatinolytic activity in WT lung extracts. Quantitative reverse transcriptase-polymerase chain reaction showed increased mRNA levels of MMP-12, MMP-14, and urokinase-type plasminogen activator after allergen exposure in the lung extracts of WT mice but not in MMP-9-deficient mice. In contrast, the expression of tissue inhibitor of metalloproteinases-1 was enhanced after allergen exposure in both groups. We conclude that MMP-9 plays a key role in the development of airway inflammation after allergen exposure.

Matrix metalloproteinases in asthma and COPD

Asthma and chronic obstructive pulmonary disease (COPD) are both highly prevalent, chronic inflammatory lung diseases that lead to significant morbidity and mortality. Matrix metalloproteinases (MMPs) are extracellular matrix degrading enzymes that play a critical role in normal development and physiological tissue remodeling and repair. In addition, they play an important role in the regulation of the kinetics and function of inflammatory cells. There is increasing evidence that MMPs are involved in the pathogenesis of both asthma and COPD, and several MMPs are possible therapeutic targets in these common chronic airway diseases.

Matrix metalloproteinase-9-mediated dendritic cell recruitment into the airways is a critical step in a mouse model of asthma

Dendritic cells (DCs) appear to be strategically implicated in allergic diseases, including asthma. Matrix metalloproteinase (MMP)-9 mediates transmigration of inflammatory leukocytes across basement membranes. This study investigated the role of MMP-9 in airway DC trafficking during allergen-induced airway inflammation. MMP-9 gene deletion affected the trafficking of pulmonary DCs in a specific way: only the inflammatory transmigration of DCs into the airway lumen was impaired, whereas DC-mediated transport of airway Ag to the thoracic lymph nodes remained unaffected. In parallel, the local production of the Th2-attracting chemokine CC chemokine ligand 17/thymus and activation-regulated chemokine, which was highly concentrated in purified lung DCs, fell short in the airways of allergen-exposed MMP-9(-/-) mice. This was accompanied by markedly reduced peribronchial eosinophilic infiltrates and impaired allergen-specific IgE production. We conclude that the specific absence of MMP-9 activity inhibits the development of allergic airway inflammation by impairing the recruitment of DCs into the airways and the local production of DC-derived proallergic chemokines.

Accelerated airway dendritic cell maturation, trafficking, and elimination in a mouse model of asthma

Pulmonary dendritic cells (DC) can induce both tolerogenic as well as inflammatory immune responses in the lung. Conversely, little is known about the impact of ongoing airway inflammation on pulmonary DC biology. In noninflammatory conditions, expression of T cell costimulatory molecules on mouse airway DCs is low and only upregulated after homing into draining thoracic lymph nodes. In this study, we reveal that ongoing allergic airway inflammation induces a premature upregulation of the T cell costimulatory molecules CD40, B7-2 and intercellular adhesion molecule 1 on DCs still present in the airways. In contrast, high surface expression of inducible costimulator ligand, involved in respiratory tolerance induction is restricted to DCs from noninflamed lungs. In addition, during inflammation the migratory flux of allergen-transporting airway DCs toward draining thoracic nodes increases both in amplitude as well as in speed. Remarkably, migratory DCs from inflamed airways are short-lived in the draining lymph nodes, a finding that is temporally associated with a marked loss of the antiapoptotic protein Bcl-2 in these cells. This study demonstrates the profound effects of ongoing allergen-driven airway inflammation on the dynamics of pulmonary DC physiology, a knowledge that could be exploited in the development of novel DC-based immunotherapies.

Indoleamine 2,3-dioxygenase, a new prognostic marker in sentinel lymph nodes of melanoma patients

BACKGROUND

Indoleamine 2,3-dioxygenase (IDO), an enzyme with immunosuppressive properties is considered as a factor that impairs the antitumour immune response in melanoma. In this study, we investigated the expression of IDO in sentinel nodes of melanoma patients to determine its prognostic relevance.

PATIENTS AND METHODS

One hundred and sixteen melanoma patients were enrolled in this study with a median follow-up time after diagnosis of 71 months. The expression of IDO and forkhead box P3 (Foxp3) in the sentinel lymph nodes was determined by immunohistochemistry and correlated with progression-free survival and overall survival. In 42 patients, regulatory T cells were investigated by flow cytometry.

RESULTS

Cox regression survival analysis showed a significant negative effect of IDO expression on progression-free survival (p = 0.015) and overall survival (p = 0.010). High IDO expression was correlated with a significant higher frequency of Foxp3-positive cells in uninvaded lymph nodes (p = 0.016). The presence of IDO expression in the sentinel nodes was not associated with an increased frequency of circulating regulatory T cells (Tregs) but was significantly correlated with an increased mean fluorescence intensity of Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) in Tregs (p = 0.019). After CD3CD28 stimulation, peripheral blood mononuclear cells of patients with high IDO expression showed a lower production of interferon-gamma (IFN-γ) (p = 0.025).

CONCLUSIONS

This study points to an independent predictive role of IDO on survival, especially in melanoma patients with uninvolved sentinel nodes. Investigating IDO expression in the sentinel nodes of melanoma patients may be a useful marker to pre-identify patients with a less favourable prognosis in stage I and II disease.

The RNA Atlas expands the catalog of human non-coding RNAs

Existing compendia of non-coding RNA (ncRNA) are incomplete, in part because they are derived almost exclusively from small and polyadenylated RNAs. Here we present a more comprehensive atlas of the human transcriptome, which includes small and polyA RNA as well as total RNA from 300 human tissues and cell lines. We report thousands of previously uncharacterized RNAs, increasing the number of documented ncRNAs by approximately 8%. To infer functional regulation by known and newly characterized ncRNAs, we exploited pre-mRNA abundance estimates from total RNA sequencing, revealing 316 microRNAs and 3,310 long non-coding RNAs with multiple lines of evidence for roles in regulating protein-coding genes and pathways. Our study both refines and expands the current catalog of human ncRNAs and their regulatory interactions. All data, analyses and results are available for download and interrogation in the R2 web portal, serving as a basis for future exploration of RNA biology and function.

Murine TLR4 is implicated in cigarette smoke-induced pulmonary inflammation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with an abnormal inflammatory response of the lungs to noxious particles or gases. We investigated whether Toll-like receptor 4 (TLR4) is implicated in cigarette smoke (CS)-induced pulmonary inflammation in a murine model of COPD.

METHODS

C3H/HeOuJ (Tlr4(WT)) and C3H/HeJ (Tlr4(defective)) mice were exposed to air or CS for 5 weeks (subacute) and 26 weeks (chronic), and pulmonary inflammation was evaluated.

RESULTS

In Tlr4(WT) mice, subacute and chronic CS exposure induced a substantial pulmonary infiltration of macrophages, neutrophils, lymphocytes and dendritic cells (DCs), that was absent in air-exposed mice. CS exposure increased the costimulatory marker expression on DCs, the levels of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-alpha) in bronchoalveolar lavage (BAL) fluid and induced the pulmonary expression of matrix metalloproteinase-12 (MMP-12), TLR4 and TLR2. In contrast, after subacute CS exposure, Tlr4(defective) mice showed a limited (5-fold lower) increase of DCs and lymphocytes in BAL fluid, lower costimulatory marker expression on DCs and lower MCP-1 and TNF-alpha levels in BAL fluid compared to Tlr4(WT) animals. After chronic CS exposure, however, the difference in pulmonary inflammation between Tlr4(WT) and Tlr4(defective) mice was less pronounced and both strains showed similar MCP-1 and TNF-alpha levels in BAL and similar pulmonary MMP-12, TLR4 and TLR2 expression.

CONCLUSIONS

We demonstrated that the TLR4 mutation in C3H/HeJ mice is protective against CS-induced pulmonary influx of neutrophils, DCs and lymphocytes upon subacute CS exposure. However, TLR4 is only of minor importance in chronic CS-induced inflammation in mice.

Allergen-induced changes in bone-marrow progenitor and airway dendritic cells in sensitized rats

Eosinophilic airway inflammation is orchestrated by T-helper (Th)-2 lymphocytes. We have previously demonstrated that dendritic cells (DC) are essential for the presentation of antigen to these Th2 cells leading to airway inflammation. Here, we have examined the presence of DC in the lungs, the kinetics of appearance, and the possible involvement of the bone-marrow progenitor for DC in a rat model of ovalbumin (OVA)-induced airway inflammation. Sensitized rats were exposed to 0, 1, 3, or 7 consecutive daily OVA aerosols. Control rats were sham sensitized and/or exposed to phosphate-buffered saline (PBS), and bronchoalveolar lavage (BAL) was performed 24 h after the last challenge. DC were identified in BAL fluid as low-density, low-autofluorescence, CD3(-), CD45RA-, OX62(+), OX6(+) cells that had long surface extensions and strong costimulatory activity. Low but detectable amounts of BAL DC were seen in sensitized, unexposed animals. After three OVA exposures, the inflammatory infiltrate consisted of CD4(+)-activated T cells, eosinophils, and monocytes. The number of BAL DC was significantly increased in OVA-sensitized/OVA-exposed animals compared with sham-sensitized or PBS-exposed animals. The kinetics of DC increase closely parallelled those in other inflammatory cells. Bone-marrow cells taken from the OVA-sensitized and -exposed group were grown in the DC growth factor granulocyte macrophage colony-stimulating factor for 6 d and the yield of OX62(+)OX6(+) DC was 60% higher compared with PBS-exposed or sham-sensitized animals. We conclude that allergen exposition in sensitized rats increases the number of DC in the airways and the production of progenitors for DC in the bone marrow.

High incidence of chromosome abnormalities in IgG3 myeloma

Chromosomes were studied in 33 untreated myeloma patients, and results were correlated with the class of Ig secreted by the myeloma cells. A high incidence of clonal karyotypic anomalies seemed to be present in IgG3 myeloma patients, in whom the disease was advanced at diagnosis and rapidly progressing. Among the chromosome anomalies, the t(11;14)(q14;q32) was particularly prominent, and this chromosome anomaly, in analogy with the Ph1 chromosome, may characterize a family of lymphoproliferative disorders.

The transcriptome of lung tumor-infiltrating dendritic cells reveals a tumor-supporting phenotype and a microRNA signature with negative impact on clinical outcome

Targeting immunomodulatory pathways has ushered a new era in lung cancer therapy. Further progress requires deeper insights into the biology of immune cells in the lung cancer micro-environment.

Dendritic cells (DCs) represent a heterogeneous and highly plastic immune cell system with a central role in controlling immune responses. The intratumoral infiltration and activation status of DCs are emerging as clinically relevant parameters in lung cancer.

In this study, we used an orthotopic preclinical model of lung cancer to dissect how the lung tumor micro-environment affects tissue-resident DCs and extract novel biologically and clinically relevant information.

Lung tumor-infiltrating leukocytes expressing generic DC markers were found to predominantly consist of CD11b⁺ cells that, compare with peritumoral lung DC counterparts, strongly overexpress the T-cell inhibitory molecule PD-L1 and acquire classical surface markers of tumor-associated macrophages (TAMs). Transcriptome analysis of these CD11b⁺ tumor-infiltrating DCs (TIDCs) indicates impaired antitumoral immunogenicity, confirms the skewing toward TAM-related features, and indicates exposure to a hypoxic environment. In parallel, TIDCs display a specific microRNA (miRNA) signature dominated by the prototypical lung cancer oncomir miR-31. In vitro, hypoxia drives intrinsic miR-31 expression in CD11b⁺ DCs. Conditioned medium of miR-31 overexpressing CD11b⁺ DCs induces pro-invasive lung cancer cell shape changes and is enriched with pro-metastatic soluble factors. Finally, analysis of TCGA datasets reveals that the TIDC-associated miRNA signature has a negative prognostic impact in non-small cell lung cancer.

Together, these data suggest a novel mechanism through which the lung cancer micro-environment exploits the plasticity of the DC system to support tumoral progression.

mRNA in cancer immunotherapy: beyond a source of antigen

mRNA therapeutics have become the focus of molecular medicine research. Various mRNA applications have reached major milestones at high speed in the immuno-oncology field. This can be attributed to the knowledge that mRNA is one of nature's core building blocks carrying important information and can be considered as a powerful vector for delivery of therapeutic proteins to the patient.For a long time, the major focus in the use of in vitro transcribed mRNA was on development of cancer vaccines, using mRNA encoding tumor antigens to modify dendritic cells ex vivo. However, the versatility of mRNA and its many advantages have paved the path beyond this application. In addition, due to smart design of both the structural properties of the mRNA molecule as well as pharmaceutical formulations that improve its in vivo stability and selective targeting, the therapeutic potential of mRNA can be considered as endless.As a consequence, many novel immunotherapeutic strategies focus on the use of mRNA beyond its use as the source of tumor antigens. This review aims to summarize the state-of-the-art on these applications and to provide a rationale for their clinical application.

Reciprocal translocation t(6;9)(p21;q33): a new characteristic chromosome anomaly in myeloid leukemias

Three patients with myeloproliferative disorders, two acute myeloid leukemias and one chronic myelocytic leukemia, were found to present a t(6;9)(p21;q33) as the sole anomaly in the leukemic cells. It is likely that this translocation is to be added to the steadily growing list of characteristic chromosome changes in human malignancy.

11q-chromosome is associated with abnormal iron stores in myelodysplastic syndromes

Nine cases of myelodysplastic syndrome with a deletion of the long arm of chromosome #11 (11q-) showed ringed sideroblasts, and three of which had an acquired sideroblastic anemia according to the criteria of the FAB classification. In contrast, among four cases of myelodysplastic syndromes with translocation of extra material to the long arm of chromosome #11 (11q+), only one showed bone marrow sideroblasts. These results strongly indicate that an 11q- chromosome is a marker of iron overload in myelodysplastic syndromes. Within the cases of 11q- associated with sideroblastosis, two cytogenetically different anomalies (i.e., terminal or interstitial deletions) were delineated.

Biomarkers for early diagnosis of malignant mesothelioma: Do we need another moonshot?

Early diagnosis of malignant pleural mesothelioma (MPM) is a challenge for clinicians. The disease is usually detected in an advanced stage which precludes curative treatment. We assume that only new and non-invasive biomarkers allowing earlier detection will result in better patient management and outcome. Many efforts have already been made to find suitable biomarkers in blood and pleural effusions, but have not yet resulted in a valid and reproducible diagnostic one. In this review, we will highlight the strengths and shortcomings of blood and fluid based biomarkers and highlight the potential of breath analysis as a non-invasive screening tool for MPM. This method seems very promising in the early detection of diverse malignancies, because exhaled breath contains valuable information on cell and tissue metabolism. Research that focuses on breath biomarkers in MPM is in its early days, but the few studies that have been performed show promising results. We believe a breathomics-based biomarker approach should be further explored to improve the follow-up and management of asbestos exposed individuals.