miR-146a-5p impairs melanoma resistance to kinase inhibitors by targeting COX2 and regulating NFkB-mediated inflammatory mediators

BACKGROUND: Targeted therapy with BRAF and MEK inhibitors has improved the survival of patients with BRAF-mutated metastatic melanoma, but most patients relapse upon the onset of drug resistance induced by mechanisms including genetic and epigenetic events. Among the epigenetic alterations, microRNA perturbation is associated with the development of kinase inhibitor resistance. Here, we identified and studied the role of miR-146a-5p dysregulation in melanoma drug resistance.METHODS: The miR-146a-5p-regulated NFkB signaling network was identified in drug-resistant cell lines and melanoma tumor samples by expression profiling and knock-in and knock-out studies. A bioinformatic data analysis identified COX2 as a central gene regulated by miR-146a-5p and NFkB. The effects of miR-146a-5p/COX2 manipulation were studied in vitro in cell lines and with 3D cultures of treatment-resistant tumor explants from patients progressing during therapy.RESULTS: miR-146a-5p expression was inversely correlated with drug sensitivity and COX2 expression and was reduced in BRAF and MEK inhibitor-resistant melanoma cells and tissues. Forced miR-146a-5p expression reduced COX2 activity and significantly increased drug sensitivity by hampering prosurvival NFkB signaling, leading to reduced proliferation and enhanced apoptosis. Similar effects were obtained by inhibiting COX2 by celecoxib, a clinically approved COX2 inhibitor.CONCLUSIONS: Deregulation of the miR-146a-5p/COX2 axis occurs in the development of melanoma resistance to targeted drugs in melanoma patients. This finding reveals novel targets for more effective combination treatment. Video Abstract

Country activities of Global Alliance against Chronic Respiratory Diseases (GARD): focus presentations at the 11th GARD General Meeting, Brussels

© Journal of Thoracic Disease. All rights reserved.The Global Alliance against Chronic Respiratory Diseases (GARD) is a voluntary network of national and international organizations, institutions and agencies led by the World Health Organization (WHO), working towards the vision of a world where all people breathe freely (1). GARD is supporting WHO in successfully implementing the WHO’s Global Action Plan for the Prevention and Control of Noncommunicable Diseases (NCDs) 2013–2020. The GARD report on GARD activities is published on a regular basis. Collaboration among GARD countries is critical for sharing experiences and providing technical assistance to developing countries based on each country’s needs (2). The annual GARD meeting is a unique opportunity for assembling all of the GARD participants from developed and developing countries: European countries, North and South American Countries, China, Vietnam as well as Eastern Mediterranean, and African countries. Coordinator for Management of NCDs in the WHO Department for Management of Noncommunicable Diseases, Disability, Violence and Injury Prevention (Cherian Varghese) is present at this meeting. The annual meeting of GARD is a forum for exchanging opinions in order to improve care for chronic respiratory diseases (CRDs) and to achieve the GARD goal—a world where all people breathe freely. Experts—in collaboration with WHO—are helping developing countries to achieve their projects regarding teaching, research and programming for CRD. Each year, there is a poster presentation session on country activities. Each participant is able to present his/her country activities that have been achieved since the last meeting. This is followed by discussion. In this paper, we summarize the posters presented during the 11th GARD general meeting. We hope that this will give readers of the GARD section an opportunity to learn for their countries. We can find all posters on the link: https://gard-breathefreely.org/resources-poster/.info:eu-repo/semantics/publishedVersio

Miaquant, a novel system for automatic segmentation, measurement, and localization comparison of different biomarkers from serialized histological slices

In the clinical practice, automatic image analysis methods quickly quantizing histological results by objective and replicable methods are getting more and more necessary and widespread. Despite several commercial software products are available for this task, they are very little flexible, and provided as black boxes without modifiable source code. To overcome the aforementioned problems, we employed the commonly used MATLAB platform to develop an automatic method, MIAQuant, for the analysis of histochemical and immunohistochemical images, stained with various methods and acquired by different tools. It automatically extracts and quantifies markers characterized by various colors and shapes; furthermore, it aligns contiguous tissue slices stained by different markers and overlaps them with differing colors for visual comparison of their localization. Application of MIAQuant for clinical research fields, such as oncology and cardiovascular disease studies, has proven its efficacy, robustness and flexibility with respect to various problems; we highlight that, the flexibility of MIAQuant makes it an important tool to be exploited for basic researches where needs are constantly changing. MIAQuant software and its user manual are freely available for clinical studies, pathological research, and diagnosis

Upper limb movements in dementia with Lewy body: a quantitative analysis

Dementia with Lewy body is a neurodegenerative disorder affecting both cognitive and motor domains. Motor impairment manifests predominantly as a symmetrical/mild asymmetrical parkinsonian syndrome that is only mildly responsive to Levodopa. To characterize motor dysfunction in dementia with Lewy body, we quantitatively assessed upper limb movements using a motion-capture system. Ten patients and ten healthy controls were tested while performing the hand-to-mouth movement of which speed, smoothness and accuracy features were measured. The results showed that individuals with dementia with Lewy body required a longer time to complete the task, particularly due to a prolonged duration of the adjusting phase (i.e., when approaching the target/mouth). The overall motor performance of dementia with Lewy body patients closely resembled what previously observed in patients affected by both Parkinson's disease and ataxia while performing the same task. Moreover, the severity of parkinsonian symptoms as assessed by the UPDRS-III scale impacted on the velocity of movement alone whereas impairment of executive functions correlated with variables related to the phase of targeting the mouth. This study provides new information about upper limb motor dysfunction in dementia with Lewy body

Nucleolar detention of NONO shields DNA double-strand breaks from aberrant transcripts

RNA-binding proteins emerge as effectors of the DNA damage response (DDR). The multifunctional non-POU domain-containing octamer-binding protein NONO/p54$^{nrb}$ marks nuclear paraspeckles in unperturbed cells, but also undergoes re-localization to the nucleolus upon induction of DNA double-strand breaks (DSBs). However, NONO nucleolar re-localization is poorly understood. Here we show that the topoisomerase II inhibitor etoposide stimulates the production of RNA polymerase II-dependent, DNA damage-inducible antisense intergenic non-coding RNA (asincRNA) in human cancer cells. Such transcripts originate from distinct nucleolar intergenic spacer regions and form DNA–RNA hybrids to tether NONO to the nucleolus in an RNA recognition motif 1 domain-dependent manner. NONO occupancy at protein-coding gene promoters is reduced by etoposide, which attenuates pre-mRNA synthesis, enhances NONO binding to pre-mRNA transcripts and is accompanied by nucleolar detention of a subset of such transcripts. The depletion or mutation of NONO interferes with detention and prolongs DSB signalling. Together, we describe a nucleolar DDR pathway that shields NONO and aberrant transcripts from DSBs to promote DNA repair

Multistep tumor genetic evolution and changes in immunogenicity trigger immune-mediated disease eradication in stage IV melanoma: lessons from a single case

Durable remissions are observed in 10%–20% of treated patients with advanced metastatic melanoma but the factors associated with long-term complete clinical responses are largely unknown. Here, we report the molecular characteristics of tumor evolution during disease progression along a 9-year clinical course in a patient with advanced disseminated melanoma who received different treatments, including trametinib, ipilimumab, radiation, vemurafenib, surgical tumor debulking and a second ipilimumab course, ultimately achieving complete long-term disease remission.Longitudinal analyses of therapies-resistant metastatic tumors revealed the effects of different treatments on tumor’s microenvironment and immunogenicity, ultimately creating a milieu favorable to immunotherapy response. Monitoring of the temporal dynamics of T cells by analysis of the T cell receptor (TCR) repertoire in the tumor and peripheral blood during disease evolution indicated that T-cell clones with common TCR rearrangements, present at low levels at baseline, were maintained and expanded after immunotherapy, and that TCR diversity increased. Analysis of genetic, molecular, and cellular components of the tumor depicted a multistep process in which treatment with kinase inhibitors strongly conditioned the immune microenvironment creating an inflamed milieu converting cold into hot tumors, while ipilimumab impacted and increased the TCR repertoire, a requirement for tumor rejection.Since the optimal sequencing of treatment with antibodies targeting immune checkpoints and kinase inhibitors for advanced melanoma is still clinically debated, this case indicates that immunotherapy success is possible even after progression on targeted therapy