125 research outputs found
Circulating Leukotriene B4 Identifies Respiratory Complications after Trauma
Background. Leukotriene B4 (LTB4), a proinflammatory lipid mediator correlates well with the acute phase of Acute Respiratory Distress Syndrome (ARDS). Therefore, LTB4-levels were investigated to determine whether they might be a useful clinical marker in predicting pulmonary complications (PC) in multiply traumatized patients. Methods: Plasma levels of LTB4 were determined in 100 patients on admission (ED) and for five consecutive days (daily). Twenty healthy volunteers served as control. LTB4-levels were measured by ELISA. Thirty patients developed PC (pneumonia, respiratory failure, acute lung injury (ALI), ARDS, pulmonary embolism) and 70 had no PC (ØPC). Results. LTB4-levels in the PC-group [127.8 pg/mL, IQR: 104–200pg/ml] were significantly higher compared to the ØPC-group on admission [95.6 pg/mL, IQR: 55–143 pg/mL] or control-group [58.4 pg/mL, IQR: 36–108 pg/mL]. LTB4 continuously declined to basal levels from day 1 to 5 without differences between the groups. The cutoff to predict PC was calculated at 109.6 pg/mL (72% specificity, 67% sensitivity). LTB4 was not influenced by overall or chest injury severity, age, gender or massive transfusion. Patients with PC received mechanical ventilation for a significantly longer period of time, and had prolonged intensive care unit and overall hospital stay. Conclusion. High LTB4-levels indicate risk for PC development in multiply traumatized patients
Brd2/4 and Myc regulate alternative cell lineage programmes during early osteoclast differentiation in vitro
Osteoclast (OC) development in response to nuclear factor kappa-Β ligand (RANKL) is critical for bone homeostasis in health and in disease. The early and direct chromatin regulatory changes imparted by the BET chromatin readers Brd2-4 and OC-affiliated transcription factors (TFs) during osteoclastogenesis are not known. Here, we demonstrate that in response to RANKL, early OC development entails regulation of two alternative cell fate transcriptional programmes, OC vs macrophage, with repression of the latter following activation of the former. Both programmes are regulated in a non-redundant manner by increased chromatin binding of Brd2 at promoters and of Brd4 at enhancers/super-enhancers. Myc, the top RANKL-induced TF, regulates OC development in co-operation with Brd2/4 and Max and by establishing negative and positive regulatory loops with other lineage-affiliated TFs. These insights into the transcriptional regulation of osteoclastogenesis suggest the clinical potential of selective targeting of Brd2/4 to abrogate pathological OC activation
The innate sensor ZBP1-IRF3 axis regulates cell proliferation in multiple myeloma
Multiple myeloma is a malignancy of plasma cells (PC) initiated and driven by primary and secondary genetic events. Nevertheless, myeloma PC survival and proliferation might be sustained by non-genetic drivers. Z-DNA-binding protein 1 (ZBP1; also known as DAI) is an interferon-inducible, Z-nucleic acid sensor that triggers RIPK3-MLKL-mediated necroptosis in mice. ZBP1 also interacts with TBK1 and the transcription factor IRF3 but the function of this interaction is unclear, and the role of ZBP1-IRF3 axis in cancer is not known. Here we show that ZBP1 is selectively expressed in late B cell development in both human and mouse cells and it is required for optimal T-cell-dependent humoral immune responses. In myeloma PC, interaction of constitutively expressed ZBP1 with TBK1 and IRF3 results in IRF3 phosphorylation. IRF3 directly binds and activates cell cycle genes, in part through co-operation with the PC lineage-defining transcription factor IRF4, and thereby promoting myeloma cell proliferation. This generates a novel, potentially therapeutically targetable and relatively selective myeloma cell addiction to the ZBP1-IRF3 axis. Our data also show a non-canonical function of constitutive ZBP1 in human cells and expand our knowledge of the role of cellular immune sensors in cancer biology
Chromatin-based, in cis and in trans regulatory rewiring underpins distinct oncogenic transcriptomes in multiple myeloma
Multiple myeloma is a genetically heterogeneous cancer of the bone marrow plasma cells (PC). Distinct myeloma transcriptome profiles are primarily driven by myeloma initiating events (MIE) and converge into a mutually exclusive overexpression of the CCND1 and CCND2 oncogenes. Here, with reference to their normal counterparts, we find that myeloma PC enhanced chromatin accessibility combined with paired transcriptome profiling can classify MIE-defined genetic subgroups. Across and within different MM genetic subgroups, we ascribe regulation of genes and pathways critical for myeloma biology to unique or shared, developmentally activated or de novo formed candidate enhancers. Such enhancers co-opt recruitment of existing transcription factors, which although not transcriptionally deregulated per se, organise aberrant gene regulatory networks that help identify myeloma cell dependencies with prognostic impact. Finally, we identify and validate the critical super-enhancer that regulates ectopic expression of CCND2 in a subset of patients with MM and in chronic lymphocytic leukemia
The coordinated action of VCP/p97 and GCN2 regulates cancer cell metabolism and proteostasis during nutrient limitation
VCP/p97 regulates numerous cellular functions by mediating protein degradation through its segregase activity. Its key role in governing protein homoeostasis has made VCP/p97 an appealing anticancer drug target. Here, we provide evidence that VCP/p97 acts as a regulator of cellular metabolism. We found that VCP/p97 was tied to multiple metabolic processes on the gene expression level in a diverse range of cancer cell lines and in patient-derived multiple myeloma cells. Cellular VCP/p97 dependency to maintain proteostasis was increased under conditions of glucose and glutamine limitation in a range of cancer cell lines from different tissues. Moreover, glutamine depletion led to increased VCP/p97 expression, whereas VCP/p97 inhibition perturbed metabolic processes and intracellular amino acid turnover. GCN2, an amino acid-sensing kinase, attenuated stress signalling and cell death triggered by VCP/p97 inhibition and nutrient shortages and modulated ERK activation, autophagy, and glycolytic metabolite turnover. Together, our data point to an interconnected role of VCP/p97 and GCN2 in maintaining cancer cell metabolic and protein homoeostasis
Systems medicine dissection of chr1q-amp reveals a novel PBX1-FOXM1 axis for targeted therapy in multiple myeloma
Understanding the biological and clinical impact ofcopy number aberrations (CNA)for the development of precision therapies in cancer remains anunmet challenge. Genetic amplification of chromosome 1q (chr1q-amp) is a major CNAconferring adverse prognosis in several types of cancer, including in the blood cancer multiple myeloma (MM). Although severalgenes across chr1q portend high-risk MM disease, the underpinning molecular aetiology remains elusive. Here, with reference to the 3D chromatin structure, we integrate MMpatient multi-omics datasets with genetic variables to obtain an associated clinical risk map across chr1q and to identify 103 adverse prognosis genes in chr1q-amp MM. Prominent amongst these genes, the transcription factor PBX1 is ectopically expressed by genetic amplification and epigenetic activation of its own preserved 3D regulatory domain. By binding to reprogrammed super-enhancers, PBX1 directly regulates critical oncogenic pathways and a FOXM1-dependent transcriptional programme. Together, PBX1 and FOXM1 activate a proliferative gene signature which predicts adverse prognosis across multiple types of cancer. Notably, pharmacological disruption of the PBX1-FOXM1 axis with existing agents (thiostrepton) and a novel PBX1 small-molecule inhibitor (T417) is selectively toxic against chr1q-amplified myeloma and solid tumour cells. Overall, our systems medicine approach successfully identifies CNA-driven oncogenic circuitries, links them to clinical phenotypes and proposes novel CNA-targeted therapystrategies in multiple myeloma and other types of cancer
Recommended from our members
Computerized Ultrasound Risk Evaluation (CURE) System: Development of Combined Transmission and Reflection Ultrasound with New Reconstruction Algorithms for Breast Imaging
Our Computerized Ultrasound Risk Evaluation (CURE) system has been developed to the engineering prototype stage and generated unique data sets of both transmission and reflection ultrasound (US). This paper will help define the clinical underpinnings of the developmental process and interpret the imaging results from a similar perspective. The CURE project was designed to incorporate numerous diagnostic parameters to improve upon two major areas of early breast cancer detection. CURE may provide improved tissue characterization of breast masses and reliable detection of abnormal microcalcifications found in some breast cancers and ductal carcinoma in situ (DCIS). Current breast US is limited to mass evaluation, whereas mammography also detects and guides biopsy of malignant calcifications. Screening with CURE remains a distant goal, but improved follow-up of mammographic abnormalities may represent a feasible breakthrough. Improved tissue characterization could result in reduction of the estimated one million benign biopsies each year in the United States, costing up to several billion dollars. Most breast calcifications are benign and comprise-80% of stereotactic biopsies guided by mammography. Ultrasound has the capability of finding some groups of calcifications, but further improvements in resolution should also address tissue characterization to define the soft tissue filling of ducts by DCIS. In this manner, CURE may be able to more accurately identify the malignant calcifications associated with progression of DCIS or early cancers. Currently, high-resolution US images of the breast are performed in the reflection mode at higher frequencies, which also limits depth of penetration. Reconstruction of reflection ultrasound images relies upon acoustic impedance differences in the tissue and includes only direct backscatter of the ultrasound signal. Resolution and tissue contrast of current US continues to improve with denser transducer arrays and image processing, but the operator dependent nature of using a moveable transducer head remains a significant problem for thorough coverage of the entire breast. We have therefore undertaken the development of a whole breast (i.e., including auxiliary tail) system, with improved resolution and tissue characterization abilities. The extensive ultrasound physics considerations, engineering, materials process development and subsequent algorithm reconstruction are beyond the scope of this initial paper. The proprietary nature of these processes will be forthcoming as the intellectual property is fully secured. We will focus here on the imaging outcomes as they apply to eventual expansion into clinical use
Histone deacetylases as new therapy targets for platinum-resistant epithelial ovarian cancer
Introduction: In developed countries, ovarian cancer is the fourth most common cancer in women. Due to the nonspecific symptomatology associated with the disease many patients with ovarian cancer are diagnosed late, which leads to significantly poorer prognosis. Apart from surgery and radiotherapy, a substantial number of ovarian cancer patients will undergo chemotherapy and platinum based agents are the mainstream first-line therapy for this disease. Despite the initial efficacy of these therapies, many women relapse; therefore, strategies for second-line therapies are required. Regulation of DNA transcription is crucial for tumour progression, metastasis and chemoresistance which offers potential for novel drug targets. Methods: We have reviewed the existing literature on the role of histone deacetylases, nuclear enzymes regulating gene transcription. Results and conclusion: Analysis of available data suggests that a signifant proportion of drug resistance stems from abberant gene expression, therefore HDAC inhibitors are amongst the most promising therapeutic targets for cancer treatment. Together with genetic testing, they may have a potential to serve as base for patient-adapted therapies
Leukotriene B-4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo
This work was supported by generous funds from the Wellcome Trust (098291/Z/12/Z to S.N.). T.C. was supported by the ERC (ENDHORET). The work was also supported in part by funds from the William Harvey Research Foundation
Effect of prior treatments on selinexor, bortezomib, and dexamethasone in previously treated multiple myeloma
Therapeutic regimens for previously treated multiple myeloma (MM) may not provide prolonged disease control and are often complicated by significant adverse events, including peripheral neuropathy. In patients with previously treated MM in the Phase 3 BOSTON study, once weekly selinexor, once weekly bortezomib, and 40 mg dexamethasone (XVd) demonstrated a significantly longer median progression-free survival (PFS), higher response rates, deeper responses, a trend to improved survival, and reduced incidence and severity of bortezomib-induced peripheral neuropathy when compared with standard twice weekly bortezomib and 80 mg dexamethasone (Vd). The pre-specified analyses described here evaluated the influence of the number of prior lines of therapy, prior treatment with lenalidomide, prior proteasome inhibitor (PI) therapy, prior immunomodulatory drug therapy, and prior autologous stem cell transplant (ASCT) on the efficacy and safety of XVd compared with Vd. In this 1:1 randomized study, enrolled patients were assigned to receive once weekly oral selinexor (100 mg) with once weekly subcutaneous bortezomib (1.3 mg/m2) and 40 mg per week dexamethasone (XVd) versus standard twice weekly bortezomib and 80 mg per week dexamethasone (Vd). XVd significantly improved PFS, overall response rate, time-to-next-treatment, and showed reduced all grade and grade ≥ 2 peripheral neuropathy compared with Vd regardless of prior treatments, but the benefits of XVd over Vd were more pronounced in patients treated earlier in their disease course who had either received only one prior therapy, had never been treated with a PI, or had prior ASCT. Treatment with XVd improved outcomes as compared to Vd regardless of prior therapies as well as manageable and generally reversible adverse events. XVd was associated with clinical benefit and reduced peripheral neuropathy compared to standard Vd in previously treated MM. These results suggest that the once weekly XVd regimen may be optimally administered to patients earlier in their course of disease, as their first bortezomib-containing regimen, and in those relapsing after ASCT. Trial registration: ClinicalTrials.gov (NCT03110562). Registered 12 April 2017. https://clinicaltrials.gov/ct2/show/NCT03110562
- …