Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 48
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Scand J Gastroenterol ; 58(11): 1321-1327, 2023.
Article in English | MEDLINE | ID: mdl-37288811

ABSTRACT

OBJECTIVES: Insights into risk factors for hepatocellular carcinoma (HCC) among patients with alcohol-related cirrhosis (ALD cirrhosis) are important for decisions about HCC surveillance. We studied the effects of continued hazardous alcohol use in ALD cirrhosis on HCC risk. METHODS: Within a nationwide registry-based cohort of patients with ALD cirrhosis, we compared HCC risk between patients with a continued hazardous alcohol use and matched comparators. We used Fine-Gray regression to compare the risk of HCC and Cox regression to compare all-cause mortality. We also included patients with ALD cirrhosis in a clinical case-control study. Cases had HCC, and controls did not. Alcohol use was quantified using the AUDIT-C-questionnaire. Logistic regression was used to analyze the association between hazardous alcohol use and HCC risk. RESULTS: In the registry-based study, we included 8,616 patients with continued hazardous alcohol use and 8,616 matched comparators. Patients with a continued hazardous alcohol use had a lower HCC risk (subdistribution hazard ratio: 0.64, 95% confidence interval [CI]: 0.57 - 0.72) and higher mortality (hazard ratio: 1.62, 95% CI: 1.56 - 1.67). In the clinical study, we included 146 patients with ALD cirrhosis of whom 53 had newly diagnosed HCC. Hazardous alcohol use was insignificantly associated with a lower HCC risk (odds ratio: 0.61, 95% CI: 0.25 - 1.46). CONCLUSIONS: Hazardous alcohol use in patients with ALD cirrhosis is associated with higher mortality and, consequently, a lower HCC risk. Even if alcohol is carcinogenic, HCC surveillance will therefore likely be more effective in patients with ALD cirrhosis without a hazardous alcohol use.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/complications , Liver Neoplasms/etiology , Liver Neoplasms/complications , Case-Control Studies , Liver Cirrhosis, Alcoholic/complications , Liver Cirrhosis, Alcoholic/epidemiology , Risk Factors , Liver Cirrhosis/complications
2.
Scand J Prim Health Care ; 41(2): 179-185, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37052881

ABSTRACT

OBJECTIVE: To characterise and explore the development in the number and content of urine samples sent from general practice in the North Denmark Region to the Department of Clinical Microbiology (DCM) at Aalborg University Hospital during a five-year period. DESIGN: A register-based study. SETTING: General practice. SUBJECTS: Urine samples received at DCM, Aalborg University Hospital from general practice between 2017 and 2022. MAIN OUTCOME MEASURES: Number and content of urine samples. RESULTS: A total of 255,271 urine samples from general practice were received at DCM, with 76.1% being from female patients. Uropathogens were identified in 43.0% of the samples. During the five-year period, a 23.0% increase in the number of urine samples per person (incidence rate ratio (IRR) 1.23, 95% CI 1.21-1.25) was observed. A slight increase in the proportion of positive cultures (risk ratio (RR) 1.03, 95% CI 1.01-1.05) was seen. No notable change in the patient population (age, gender) was observed. Overall, Escherichia coli was the most identified uropathogen (60.4%) followed by Klebsiella spp. (8.7%) and Enterococcus spp. (7.7%). Distribution of the various uropathogens differed slightly depending on patient gender and age, importantly E. coli was less frequently observed in males aged >65 years. CONCLUSION: During the past five years an increasing amount of urine cultures have been requested at DCM from general practice. Importantly, the cause(s) of this increasing demand needs to be explored further in future studies.


Appropriate diagnostics of urinary tract infections can reduce the use of antibiotics in general practice.From 2017 to 2022 a 23% increase per person in requested urine cultures from general practice was observed.A slight increase in positive cultures was found, but no notable change in the patient population (age, gender) was seen.E. coli was the most identified uropathogen independent of gender and age, however, the proportion differed within the various groups.


Subject(s)
General Practice , Urinary Tract Infections , Male , Humans , Female , Escherichia coli , Urinary Tract Infections/epidemiology , Urinalysis , Denmark , Anti-Bacterial Agents/therapeutic use
3.
Neuropathol Appl Neurobiol ; 48(2): e12772, 2022 02.
Article in English | MEDLINE | ID: mdl-34713474

ABSTRACT

AIMS: Glioblastomas are heterogeneous tumours with a rich tumour microenvironment particularly comprised of tumour-associated microglia/macrophages (TAMs), but also containing a population of dedifferentiated/stem-like glioblastoma cells. Both cell populations contribute to tumour aggressiveness and immune evasion through the actions of various signalling molecules. The scavenger and pattern recognition receptor CD204 is associated with a pro-tumourigenic phenotype of TAMs and has a negative prognostic value. Our objective was to investigate the possible interaction between TAMs and dedifferentiated glioblastoma cells and characterise the myeloid phenotype of CD204-enriched glioblastomas. METHODS: Double immunohistochemistry and cell counting was performed on eight glioblastoma samples to estimate the expression and interaction level between dedifferentiated/stem-like tumour cells and TAMs. Using the NanoString technology, myeloid transcriptome profiling was performed on 46 glioblastomas, which had been selected based on their protein expression levels of CD204 and ionised calcium-binding adaptor molecule-1 (IBA1). The results were validated by immunohistochemistry and in silico gene expression analyses. RESULTS: TAMs especially CD204+ TAMs accumulated in perivascular and perinecrotic niches in close proximity to podoplanin+ glioblastoma cells. Gene profiling revealed that CD204-enriched glioblastoma has a unique signature with upregulation of genes related to hypoxia, angiogenesis and invasion, including interleukin-6. The gene signature favoured a poor prognosis in patients with glioblastoma. CONCLUSIONS: This is the first study to characterise the role of CD204 in the myeloid microenvironment of glioblastoma. Our results support the unfavourable prognostic impact of CD204 and suggest that CD204 and interleukin-6 could serve as targets for re-education of TAMs and potentiation of current anti-glioma therapy.


Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , Inflammation/metabolism , Interleukin-6/metabolism , Macrophages/metabolism , Microglia/metabolism , Aged , Biomarkers, Tumor/metabolism , Brain Neoplasms/pathology , Female , Glioblastoma/pathology , Humans , Immunohistochemistry , Inflammation/pathology , Macrophages/pathology , Male , Microglia/pathology , Middle Aged , Prognosis , Tumor Microenvironment
4.
Scand J Clin Lab Invest ; 82(4): 261-266, 2022 07.
Article in English | MEDLINE | ID: mdl-35758940

ABSTRACT

We have established and describe two measurement procedures to diagnose possible zinc (Zn) deficiency; albumin-corrected Zn concentration and available free Zn-binding capacity. Reference intervals for both biomarkers were established in healthy adults from the Danish population. The clinical usefulness of the measurement procedures was investigated in patients with cirrhosis and in patients given parenteral nutrition due to short bowel syndrome. The results of both methods indicate that there is a risk of overdiagnosing Zn deficiency based on low plasma Zn concentrations. Needless Zn supplementation may thus be avoided by using the albumin-corrected Zn concentration or available free Zn-binding capacity.


Subject(s)
Albumins , Zinc , Adult , Biomarkers , Humans
5.
Pancreatology ; 21(3): 530-543, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33637450

ABSTRACT

BACKGROUND/OBJECTIVES: Various classifications of pancreatic ductal adenocarcinoma (PDAC) based on RNA profiling resulted in two main subtypes. Kalimuthu and coworkers proposed a morphology-based classification that concurred with these subtypes. Immune therapy approaches in PDAC were so far disappointing. Morphologic PDAC subtypes may differ regarding key immune-oncology pathways. We aimed to examine the reproducibility and prognostic value of Kalimuthu's morphologic classification, and to evaluate differences between subtypes regarding gene expression related to tumor biology and immune-oncology. METHODS: PDAC specimens from 196 patients were included, 108 consecutive chemotherapy-naïve surgical specimens and 88 endoscopic ultrasound-guided fine needle biopsies (EUS-FNBs). The specimens were evaluated as per Kalimuthu by two pancreatic pathologists, resulting in Group A and Group B tumors. Digital mRNA expression profiling was performed, on the surgical specimens using the NanoString IO360 panel of 770 key tumor biology related and 30 custom-genes, and on the EUS-FNBs using a targeted panel of 123 genes. RESULTS: Morphologic subtyping reached substantial interobserver agreement between the two pathologists. In the surgical and EUS-FNB cohorts, 44.4% and 38.6% were Group A tumors, which were associated with improved survival. Group A showed higher expression of immune-related genes and cytokine/chemokine/interleukin signaling and Group B of genes related to cancer cell proliferation and cell cycle regulation. Hierarchical clustering based on significant differences in gene expression levels between Groups A and B revealed clusters with prognostic value. CONCLUSIONS: Morphologic subtyping according to Kalimuthu is reproducible and holds prognostic value, in surgical as well as EUS-FNB specimens. As upregulation of immune-related genes was found in Group A, future studies should evaluate the potential of immune therapy approaches with special emphasis on this subtype of PDAC.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Pancreatic Ductal/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Pancreatic Neoplasms/genetics , Transcriptome , Aged , Aged, 80 and over , Carcinoma, Pancreatic Ductal/classification , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/surgery , Endoscopic Ultrasound-Guided Fine Needle Aspiration , Female , Humans , Male , Middle Aged , Neoplasm Grading , Observer Variation , Pancreatic Neoplasms/classification , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Prognosis , Reproducibility of Results
6.
Acta Derm Venereol ; 101(3): adv00413, 2021 Mar 11.
Article in English | MEDLINE | ID: mdl-33686443

ABSTRACT

Mycosis fungoides is the most common type of cutaneous T-cell lymphoma. The inflammatory micro-environment in mycosis fungoides is complex. There is accumulating evidence that the neoplastic T-cells take control of the microenvironment and thereby promote their own expansion by suppressing cellular immunity. B-cells have proved to be upregulated in large-cell transformed mycosis fungoides, and could potentially play a role in disease progression. To investigate the presence of B-cells in mycosis fungoides compared with controls, this study analysed 85 formalin-fixed and paraffin-embedded mycosis fungoides biopsies. MS4A1 gene expression was significantly upregulated in mycosis fungoides compared with controls (p < 0.0001) and further upregulated in disease progression, (p = 0.001). Digital quantification of PAX5+/CD20+ cells confirmed the increased presence of B-cells in mycosis fungoides compared with controls. No co-labelling of CD3/CD20 was observed in the neoplastic T-cells. This study found a significantly increased presence of B-cells in the tumour-associated microenvironment in mycosis fungoides. These findings could potentially lead to new treatment strategies for mycosis fungoides.


Subject(s)
Lymphoma, T-Cell, Cutaneous , Mycosis Fungoides , Skin Neoplasms , Antigens, CD20 , B-Lymphocytes , Humans , Mycosis Fungoides/genetics , Skin Neoplasms/genetics , Tumor Microenvironment
7.
Glob Chang Biol ; 26(11): 6616-6629, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32311220

ABSTRACT

Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long-term average thermal conditions at coarse spatial resolutions only. Hence, many climate-forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particularly important in relation to effects of observation height (e.g. vegetation, snow and soil characteristics) and in habitats varying in their exposure to radiation, moisture and wind (e.g. topography, radiative forcing or cold-air pooling). Since organisms living close to the ground relate more strongly to these microclimatic conditions than to free-air temperatures, microclimatic ground and near-surface data are needed to provide realistic forecasts of the fate of such organisms under anthropogenic climate change, as well as of the functioning of the ecosystems they live in. To fill this critical gap, we highlight a call for temperature time series submissions to SoilTemp, a geospatial database initiative compiling soil and near-surface temperature data from all over the world. Currently, this database contains time series from 7,538 temperature sensors from 51 countries across all key biomes. The database will pave the way toward an improved global understanding of microclimate and bridge the gap between the available climate data and the climate at fine spatiotemporal resolutions relevant to most organisms and ecosystem processes.


Subject(s)
Ecosystem , Microclimate , Climate Change , Snow , Temperature
8.
Liver Int ; 40(7): 1701-1712, 2020 07.
Article in English | MEDLINE | ID: mdl-32339377

ABSTRACT

BACKGROUND: Alcoholic liver disease (ALD) is a public health concern that is the cause of half of all cirrhosis-related deaths. Early detection of fibrosis, ideally in the precirrhotic stage, is a key strategy for improving ALD outcomes and for preventing progression to cirrhosis. Previous studies identified the blood-borne marker human microfibrillar-associated protein 4 (MFAP4) as a biomarker for detection of hepatitis C virus (HCV)-related fibrosis. AIM: To evaluate the diagnostic accuracy of MFAP4 to detect ALD-induced fibrosis. METHOD: We performed a prospective, liver biopsy-controlled study involving 266 patients with prior or current alcohol overuse. Patients were split into a training and a validation cohort. RESULTS: MFAP4 was present in fibrotic hepatic tissue and serum MFAP4 levels increased with fibrosis grade. The area under the receiver operating characteristic curve (AUROC) for detection of cirrhosis was 0.91 (95% CI 0.85-0.96) in the training cohort and 0.91 (95% CI 0.79-1.00) in the validation cohort. For detection of advanced fibrosis, the AUROC was 0.88 (95% CI 0.81-0.94) in the training cohort and 0.92 (95% CI 0.83-1.00) in the validation cohort. The diagnostic accuracy did not differ between MFAP4 and the enhanced liver fibrosis (ELF) test or transient elastography (TE) in an intention-to-diagnose analysis. MFAP4 did not predict hepatic decompensation in a time-to-decompensation analysis in a subgroup of patients with cirrhosis. CONCLUSION: MFAP4 is a novel biomarker that can detect ALD-related fibrosis with high accuracy.


Subject(s)
Elasticity Imaging Techniques , Liver Diseases, Alcoholic , Biopsy , Carrier Proteins , Extracellular Matrix Proteins , Glycoproteins , Humans , Liver/pathology , Liver Cirrhosis/diagnosis , Liver Cirrhosis/pathology , Liver Diseases, Alcoholic/diagnosis , Liver Diseases, Alcoholic/pathology , Prospective Studies , ROC Curve
9.
J Neurooncol ; 147(1): 1-14, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31960234

ABSTRACT

PURPOSE: Isocitrate dehydrogenase 1 (IDH1) mutations are associated with improved survival in gliomas. Depending on the IDH1 status, TERT promoter mutations affect prognosis. IDH1 mutations are associated with alpha-thalassemia/mental retardation syndrome X-linked (ATRX) mutations and alternative lengthening of telomeres (ALT), suggesting an interaction between IDH1 and telomeres. However, little is known how IDH1 mutations affect telomere maintenance. METHODS: We analyzed cell-specific telomere length (CS-TL) on a single cell level in 46 astrocytoma samples (WHO II-IV) by modified immune-quantitative fluorescence in situ hybridization, using endothelial cells as internal reference. In the same samples, we determined IDH1/TERT promoter mutation status and ATRX expression. The interaction of IDH1R132H mutation and CS-TL was studied in vitro using an IDH1R132H doxycycline-inducible glioma cell line system. RESULTS: Virtually all ALTpositive astrocytomas had normal TERT promoter and lacked ATRX expression. Further, all ALTpositive samples had IDH1R132H mutations, resulting in a significantly longer CS-TL of IDH1R132H gliomas, when compared to their wildtype counterparts. Conversely, TERT promotor mutations were associated with IDHwildtype, ATRX expression, lack of ALT and short CS-TL. ALT, TERT promoter mutations, and CS-TL remained without prognostic significance, when correcting for IDH1 status. In vitro, overexpression of IDHR132H in the glioma cell line LN319 resulted in downregulation of ATRX and rapid TERT-independent telomere lengthening consistent with ALT. CONCLUSION: ALT is the major telomere maintenance mechanism in IDHR132H mutated astrocytomas, while TERT promoter mutations were associated with IDHwildtype glioma. IDH1R132H downregulates ATRX expression in vitro resulting in ALT, which may contribute to the strong association of IDH1R132H mutations, ATRX loss, and ALT.


Subject(s)
Astrocytoma/genetics , Brain Neoplasms/genetics , Isocitrate Dehydrogenase/genetics , Telomerase/genetics , Telomere Homeostasis/genetics , X-linked Nuclear Protein/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Isocitrate Dehydrogenase/metabolism , Male , Middle Aged , Mutation , Single-Cell Analysis , Tumor Cells, Cultured , Young Adult
10.
Surgeon ; 18(6): 344-348, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32044289

ABSTRACT

INTRODUCTION: Glioblastoma has a high mortality rate. Current treatment includes largest possible surgical resection of the tumour using neuronavigation and fluorescence to better identify tumour tissue. In recent years, sodium fluorescein has been reintroduced in neurosurgery as a fluorescence to increase the resection rate. In this study we aimed to measure the surgeons experience of using sodium fluorescein to locate and remove tumour tissue. Furthermore we describe a case of sodium fluorescein tissue distribution. MATERIAL AND METHODS: 13 patients with glioblastoma and seven patients with cerebral metastases undergoing surgical resection were included. Surgery was performed using microscope alternating between white light and the YELLOW 560 filter, which visualized sodium fluorescein. Surgeons graded its usability in terms of location and removal on a scale from one to four. The resection rate was determined by neuroradiologists. Tissue samples obtained during surgery were analysed in relation to fluorescence and dysmorphic cells. RESULTS: Surgeons reported high usability in terms of location and removal of tumours using sodium fluorescein with medians of four in all groups, except for sub-total resections which had a median of three. Surgical complications were minimal and both resection rate and survival rate was within international standards. Histological analysis showed a visual correlation between tumorous tissue and intensity of fluorescence. CONCLUSION: Sodium fluorescence is an effective and useful tool for surgeons during fluorescence-guided surgery for the resection of glioblastoma and cerebral metastases.


Subject(s)
Brain Neoplasms/surgery , Fluorescein , Fluorescent Dyes , Glioblastoma/surgery , Aged , Aged, 80 and over , Brain Neoplasms/mortality , Brain Neoplasms/pathology , Cohort Studies , Female , Glioblastoma/mortality , Glioblastoma/pathology , Humans , Male , Middle Aged , Practice Patterns, Physicians'
11.
BMC Cancer ; 18(1): 270, 2018 03 09.
Article in English | MEDLINE | ID: mdl-29523123

ABSTRACT

BACKGROUND: We have previously identified tissue inhibitor of metalloproteinases-1 (TIMP-1) as a prognostic marker in glioblastomas. TIMP-1 has been associated with chemotherapy resistance, and CD63, a known TIMP-1-binding protein, has been suggested to be responsible for this effect. The aim of this study was to assess CD63 expression in astrocytomas focusing on the prognostic potential of CD63 alone and in combination with TIMP-1. METHODS: CD63 expression was investigated immunohistochemically in a cohort of 111 astrocytomas and correlated to tumor grade and overall survival by semi-quantitative scoring. CD63 expression in tumor-associated microglia/macrophages was examined by double-immunofluorescence with ionized calcium-binding adapter molecule 1 (Iba1). The association between CD63 and TIMP-1 was investigated using previously obtained TIMP-1 data from our astrocytoma cohort. Cellular co-expression of TIMP-1 and CD63 as well as TIMP-1 and the tumor stem cell-related markers CD133 and Sox2 was investigated with immunofluorescence. TIMP-1 and CD63 protein interaction was detected by an oligonucleotide-based proximity ligation assay and verified using co-immunoprecipitation. RESULTS: The expression of CD63 was widely distributed in astrocytomas with a significantly increased level in glioblastomas. CD63 levels did not significantly correlate with patient survival at a protein level, and CD63 did not augment the prognostic significance of TIMP-1. Up to 38% of the CD63+ cells expressed Iba1; however, Iba1 did not appear to impact the prognostic value of CD63. A significant correlation was found between TIMP-1 and CD63, and the TIMP-1 and CD63 proteins were co-expressed at the cellular level and located in close molecular proximity, suggesting that TIMP-1 and CD63 could be co-players in glioblastomas. Some TIMP-1+ cells expressed CD133 and Sox2. CONCLUSION: The present study suggests that CD63 is highly expressed in glioblastomas and that TIMP-1 and CD63 interact. CD63 does not add to the prognostic value of TIMP-1. Co-expression of TIMP-1 and stem cell markers as well as the wide expression of CD63 might suggest a role for TIMP-1 and CD63 in glioblastoma stemness.


Subject(s)
Biomarkers, Tumor/metabolism , Cell Membrane/metabolism , Glioblastoma/metabolism , Glioblastoma/pathology , Neoplastic Stem Cells/pathology , Tetraspanin 30/metabolism , Tissue Inhibitor of Metalloproteinase-1/metabolism , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Female , Follow-Up Studies , Humans , Immunoprecipitation , Male , Middle Aged , Neoplastic Stem Cells/metabolism , Prognosis , Survival Rate , Young Adult
12.
J Neurooncol ; 138(1): 49-53, 2018 May.
Article in English | MEDLINE | ID: mdl-29404978

ABSTRACT

Epileptic seizures are an important cause of morbidity in glioma patients. Substantial lines of evidence support the concept of the excitatory neurotransmitter glutamate being a crucial mediator of glioma-associated seizures. In gliomas, non-vesicular secretion of glutamate via the cystine-glutamate exchanger (SLC7A11, xCT) constitutes the main mechanism contributing to high extracellular glutamate concentrations. However, a convincing "proof-of-relevance" of this mechanism in patient material is lacking. A cohort of 229 consecutive patients with newly diagnosed glioma was analyzed with respect to presence, time course, and severity of epileptic seizures. 14 patients were excluded due to previous epileptic seizures, insufficient clinical data or insufficient tumor material. The maximal immunohistochemical expression of xCT was determined in 1-3 independent samples from central tumor areas of each tumor using tissue microarrays. In addition to histological grading of the tumors, isocitrate dehydrogenase 1 (IDH1) R132H mutational status was determined by immunohistochemistry. 215 consecutive glioma patients were included in the study (7.4% grade II, 7.0% grade III, 85.6% grade IV). High xCT expression was significantly associated with seizures at onset (p = 0.05) but not with development of seizures or with refractory seizures. Low-grade gliomas (WHO II/III) had lower xCT expression than glioblastoma (p = 0.001), and tumors without IDH1 R132H mutation tended to have higher xCT levels (p = 0.07). In a multivariate analysis, high xCT expression and WHO tumor grade but not IDH1 R132H mutation, were significantly associated with epileptic seizures at diagnosis (odds ratio 2.2, p = 0.02). Further, xCT expression did not correlate with survival (p = 0.27, log-rank test). Thus, high xCT expression is an independent marker for glioma-associated seizures at diagnosis especially in high-grade glioma, but is not associated with worse survival in our cohort.


Subject(s)
Amino Acid Transport System y+/metabolism , Brain Neoplasms/complications , Glioma/complications , Seizures/etiology , Seizures/metabolism , Aged , Amino Acid Transport System y+/genetics , Brain Neoplasms/genetics , Cohort Studies , Female , Gene Expression Regulation, Neoplastic/physiology , Glioma/genetics , Humans , Isocitrate Dehydrogenase/genetics , Isocitrate Dehydrogenase/metabolism , Male , Middle Aged , Multivariate Analysis , Mutation/genetics , Survival Analysis , Tissue Array Analysis
13.
BMC Ecol ; 18(1): 29, 2018 08 30.
Article in English | MEDLINE | ID: mdl-30165832

ABSTRACT

BACKGROUND: Shrub cover in arctic and alpine ecosystems has increased in recent decades, and is predicted to further increase with climate change. Changes in shrub abundance may alter ecosystem carbon (C) sequestration and storage, with potential positive feedback on global C cycling. Small and large herbivores may reduce shrub expansion and thereby counteract the positive feedback on C cycling, but herbivore pressures have also changed in the alpine-arctic tundra; the increased shrub cover together with changes in herbivore pressure is leading to unpredictable changes in carbon sequestration and storage. In this study we investigate the importance of herbivory and shrub introduction for carbon sequestration in the short term. We measured standing biomass and daytime mid-growing season carbon fluxes in plots in a full factorial design where we excluded small and large mammalian herbivores and introduced Salix by planting Salix transplants. We used three study sites: one Empetrum-dominated heath, one herb- and cryptogam-dominated meadow, and one Salix-dominated shrub community in the low-alpine zone of the Dovre Mountains, Central Norway. RESULTS: After 2 years, significant treatment effects were recorded in the heath community, but not in the meadow and shrub communities. In the heath community cessation of herbivory increased standing biomass due to increased biomass of dwarf shrubs. Cessation of herbivory also reduced biomass of bryophytes and ecosystem respiration (ER). Except for an increase in biomass of deciduous shrubs caused by the Salix introduction, the only effect of Salix introduction was an increase in biomass of graminoids in the heath. CONCLUSIONS: Our short-term study demonstrated that herbivore exclusion had small but still significant effects on heath vegetation, whereas such effects were not apparent in the herb-and cryptogam-dominated meadow and the Salix-dominated shrub community. Following the treatments over more years is needed to estimate the long-term effects on community structure and the consequences for C sequestration in the three plant communities. Such data are important for predicting the impact of shrub expansion on C budgets from alpine regions.


Subject(s)
Carbon Sequestration , Herbivory , Trees/physiology , Tundra , Biomass , Carbon Cycle , Climate Change , Norway , Plant Physiological Phenomena
14.
Stem Cells ; 34(8): 2026-39, 2016 08.
Article in English | MEDLINE | ID: mdl-27145382

ABSTRACT

Shifting the balance away from tumor-mediated immune suppression toward tumor immune rejection is the conceptual foundation for a variety of immunotherapy efforts currently being tested. These efforts largely focus on activating antitumor immune responses but are confounded by multiple immune cell populations, including myeloid-derived suppressor cells (MDSCs), which serve to suppress immune system function. We have identified immune-suppressive MDSCs in the brains of GBM patients and found that they were in close proximity to self-renewing cancer stem cells (CSCs). MDSCs were selectively depleted using 5-flurouracil (5-FU) in a low-dose administration paradigm, which resulted in prolonged survival in a syngeneic mouse model of glioma. In coculture studies, patient-derived CSCs but not nonstem tumor cells selectively drove MDSC-mediated immune suppression. A cytokine screen revealed that CSCs secreted multiple factors that promoted this activity, including macrophage migration inhibitory factor (MIF), which was produced at high levels by CSCs. Addition of MIF increased production of the immune-suppressive enzyme arginase-1 in MDSCs in a CXCR2-dependent manner, whereas blocking MIF reduced arginase-1 production. Similarly to 5-FU, targeting tumor-derived MIF conferred a survival advantage to tumor-bearing animals and increased the cytotoxic T cell response within the tumor. Importantly, tumor cell proliferation, survival, and self-renewal were not impacted by MIF reduction, demonstrating that MIF is primarily an indirect promoter of GBM progression, working to suppress immune rejection by activating and protecting immune suppressive MDSCs within the GBM tumor microenvironment. Stem Cells 2016;34:2026-2039.


Subject(s)
Brain Neoplasms/immunology , Glioblastoma/immunology , Immune Evasion , Macrophage Migration-Inhibitory Factors/metabolism , Myeloid-Derived Suppressor Cells/metabolism , Neoplastic Stem Cells/metabolism , Animals , Arginase/metabolism , Brain Neoplasms/pathology , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Line, Tumor , Cell Survival/drug effects , Culture Media, Conditioned/pharmacology , Female , Glioblastoma/pathology , Humans , Immune Evasion/drug effects , Mice, Inbred C57BL , Mice, Nude , Myeloid-Derived Suppressor Cells/drug effects , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , Tumor Microenvironment/drug effects
15.
J Neurooncol ; 135(1): 107-117, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28677106

ABSTRACT

Gliomas are among the most lethal cancers, being highly resistant to both chemo- and radiotherapy. The expression of junctional adhesion molecule-A (JAM-A) was recently identified on the surface of stem cell-like brain tumor-initiating cells and suggested to function as a unique glioblastoma niche adhesion factor influencing the tumorigenic potential of brain tumor-initiating cells. We have recently identified high JAM-A expression to be associated with poor outcome in glioblastomas, and our aim was to further investigate the expression of JAM-A in gliomas focusing especially on the prognostic value in WHO grade II and III gliomas. JAM-A protein expression was evaluated by immunohistochemistry and advanced quantitative image analysis with continuous estimates of staining intensity. The JAM-A antibody stained tumor cell membranes and cytoplasm to various extent in different glioma subtypes, and the intensity was higher in glioblastomas than low-grade gliomas. We could not detect an association with overall survival in patients with grade II and III tumors. Double-immunofluorescence stainings in glioblastomas revealed co-expression of JAM-A with CD133, SOX2, nestin, and GFAP in tumor cells as well as some co-expression with the microglial/macrophage marker IBA-1. In conclusion, JAM-A expression was higher in glioblastomas compared to low-grade gliomas and co-localized with recognized stem cell markers suggesting an association of JAM-A with glioma aggressiveness. No significant association between JAM-A expression and overall survival was found in grade II and III gliomas. Further research is needed to determine the function and clinical impact of JAM-A in gliomas.


Subject(s)
Brain Neoplasms/metabolism , Cell Adhesion Molecules/metabolism , Glioma/metabolism , Receptors, Cell Surface/metabolism , AC133 Antigen/metabolism , Adult , Biomarkers, Tumor/metabolism , Brain/metabolism , Brain/pathology , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Calcium-Binding Proteins , Cohort Studies , DNA-Binding Proteins/metabolism , Female , Gene Expression , Glial Fibrillary Acidic Protein/metabolism , Glioma/genetics , Glioma/pathology , Humans , Male , Microfilament Proteins , Middle Aged , Neoplasm Grading , Nestin , Prognosis , RNA, Messenger/metabolism , SOXB1 Transcription Factors/metabolism , Survival Analysis
16.
J Neurooncol ; 130(1): 53-62, 2016 10.
Article in English | MEDLINE | ID: mdl-27510953

ABSTRACT

Glioblastoma (GBM) is the most frequent and malignant brain tumor with an overall survival of only 14.6 months. Although these tumors are treated with surgery, radiation and chemotherapy, recurrence is inevitable. A critical population of tumor cells in terms of therapy, the so-called cancer stem cells (CSCs), has been identified in gliomas and many other cancers. These tumor cells have a stem cell-like phenotype and are suggested to be responsible for tumor growth, chemo- and radio-resistance as well as recurrence. However, functional evidence for migrating glioma cells having a stem cell-like phenotype is currently lacking. In the present study, the aim was to characterize the phenotype of migrating tumor cells using a novel migration assay based on serum-free stem cell medium and patient-derived spheroid cultures. The results showed pronounced migration of five different GBM spheroid cultures, but not of the commercial cell line U87MG. An in vitro limiting dilution assay showed preserved but reduced spheroid formation capacity of migrating cells. Orthotopic xenografting in mice showed preserved but reduced tumorigenic capacity. Profiling of mRNAs revealed no significant deregulation of 16 predefined CSC-related genes and the HOX-gene list in migrating cells compared to spheroids. Determination of GBM molecular subtypes revealed that subtypes of spheroids and migrating cells were identical. In conclusion, migrating tumor cells preserve expression of stem cell markers and functional CSC characteristics. Since CSCs are reported to be highly resistant to therapy, these results emphasize that the CSC phenotype should be taken into consideration in future treatment of GBMs.


Subject(s)
Brain Neoplasms/pathology , Cell Movement/physiology , Gene Expression Regulation, Neoplastic/physiology , Glioma/pathology , Neoplastic Stem Cells/physiology , Transplantation, Heterologous , AC133 Antigen/metabolism , Animals , Brain Neoplasms/mortality , Cell Line, Tumor , Cell Movement/drug effects , Culture Media, Serum-Free/pharmacology , Glioma/mortality , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Kaplan-Meier Estimate , Mice , Microarray Analysis , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , RNA, Messenger/metabolism , SOXB1 Transcription Factors/metabolism , Spheroids, Cellular , Time Factors
17.
J Neurooncol ; 128(3): 395-404, 2016 07.
Article in English | MEDLINE | ID: mdl-27063952

ABSTRACT

Glioblastomas always recur despite surgery, radiotherapy and chemotherapy. A key player in the therapeutic resistance may be immature tumor cells with stem-like properties (TSCs) escaping conventional treatment. A group of promising molecular targets are microRNAs (miRs). miRs are small non-coding RNAs exerting post-transcriptional regulation of gene expression. In this study we aimed to identify over-expressed TSC-related miRs potentially amenable for therapeutic targeting. We used non-differentiated glioblastoma spheroid cultures (GSCs) containing TSCs and compared these to xenografts using a NanoString nCounter platform. This revealed 19 over-expressed miRs in the non-differentiated GSCs. Additionally, non-differentiated GSCs were compared to neural stem cells (NSCs) using a microarray platform. This revealed four significantly over-expressed miRs in the non-differentiated GSCs in comparison to the NSCs. The three most over-expressed miRs in the non-differentiated GSCs compared to xenografts were miR-126, -137 and -128. KEGG pathway analysis suggested the main biological function of these over-expressed miRs to be cell-cycle arrest and diminished proliferation. To functionally validate the profiling results suggesting association of these miRs with stem-like properties, experimental over-expression of miR-128 was performed. A consecutive limiting dilution assay confirmed a significantly elevated spheroid formation in the miR-128 over-expressing cells. This may provide potential therapeutic targets for anti-miRs to identify novel treatment options for GBM patients.


Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , MicroRNAs/metabolism , Neoplastic Stem Cells/metabolism , Animals , Brain Neoplasms/pathology , Cell Line, Tumor , Cells, Cultured , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Glioblastoma/pathology , Heterografts , Humans , Male , Microarray Analysis , Neoplasm Transplantation , Neural Stem Cells/metabolism , Rats, Nude , Spheroids, Cellular/transplantation
18.
Adv Exp Med Biol ; 853: 111-38, 2015.
Article in English | MEDLINE | ID: mdl-25895710

ABSTRACT

Glioblastoma remains a tumor with a dismal prognosis because of failure of current treatment. Glioblastoma cells with stem cell (GSC) properties survive chemotherapy and give rise to tumor recurrences that invariably result in the death of the patients. Here we summarize the current knowledge on chemoresistance of malignant glioma with a strong focus on GSC. Chemoresistant GSC are the most likely cause of tumor recurrence, but it remains controversial if GSC and under which conditions GSC are more chemoresistant than non-GSC within the tumor. Regardless of this uncertainty, the chemoresistance varies and it is mainly mediated by intrinsic factors. O6-methyl-guanidine methyltransferase (MGMT) remains the most potent mediator of chemoresistance, but disturbed mismatch repair system and multidrug resistance proteins contribute substantially. However, the intrinsic resistance by MGMT expression is regulated by extrinsic factors like hypoxia increasing MGMT expression and thereby resistance to alkylating chemotherapy. The search of new biomarkers helping to predict the tumor response to chemotherapy is ongoing and will complement the already known markers like MGMT.


Subject(s)
Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/drug therapy , Drug Resistance, Neoplasm , Glioma/drug therapy , Neoplastic Stem Cells/drug effects , Animals , Brain Neoplasms/genetics , Brain Neoplasms/pathology , DNA Mismatch Repair/genetics , DNA Modification Methylases/physiology , DNA Repair Enzymes/physiology , Dacarbazine/analogs & derivatives , Dacarbazine/therapeutic use , Drug Resistance, Neoplasm/genetics , Glioma/genetics , Glioma/pathology , Humans , Neoplastic Stem Cells/pathology , Temozolomide , Tumor Suppressor Proteins/physiology
19.
BMJ Case Rep ; 17(9)2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39322572

ABSTRACT

Haemophagocytic lymphohistiocytosis (HLH) is a syndrome with an abnormal activation of the immune system and is associated with a high mortality even with treatment. We present a case of a woman in her mid-50s who developed HLH triggered by miliary tuberculosis (TB) while receiving a tumour necrosis factor alpha inhibitor.The patient was admitted with a high fever and respiratory pain. Her condition deteriorated despite empirical treatment. Diagnosis of HLH was established based on clinical presentation, H-score and HLH-04 criteria. Concurrently, miliary TB was identified as the trigger. She was treated with anti-tuberculous therapy and HLH-directed treatment with dexamethasone, etoposide and anakinra. Initial improvement was observed, leading to the withholding of HLH-orientated treatment. However, several relapses occurred, necessitating prolonged HLH treatment.A literature review corroborated the importance of combined anti-tuberculous and immunosuppressive therapy for managing HLH. This case underscores the necessity of timely and comprehensive management of HLH-oriented treatment.


Subject(s)
Lymphohistiocytosis, Hemophagocytic , Tuberculosis, Miliary , Humans , Lymphohistiocytosis, Hemophagocytic/drug therapy , Lymphohistiocytosis, Hemophagocytic/diagnosis , Tuberculosis, Miliary/drug therapy , Tuberculosis, Miliary/complications , Tuberculosis, Miliary/diagnosis , Female , Middle Aged , Antitubercular Agents/therapeutic use , Dexamethasone/therapeutic use , Dexamethasone/administration & dosage , Immunosuppressive Agents/therapeutic use , Etoposide/therapeutic use , Interleukin 1 Receptor Antagonist Protein/therapeutic use , Immunosuppression Therapy/adverse effects
20.
Radiother Oncol ; 193: 110149, 2024 04.
Article in English | MEDLINE | ID: mdl-38341096

ABSTRACT

BACKGROUND AND PURPOSE: Reliable and accessible biomarkers for patients with Head and Neck Squamous Cell Carcinoma (HNSCC) are warranted for biologically driven radiotherapy (RT). This study aimed to investigate the prognostic value of putative cancer stem cell (CSC) markers, hypoxia, and tumor volume using loco-regional high-dose failure (HDF) as endpoint. MATERIALS AND METHODS: Tumor tissue was retrieved from patients treated with primary chemo-(C-)RT and nimorazole for HNSCC in the Danish Head and Neck Cancer Study Group (DAHANCA) 19 study. Tumor volume, hypoxic classification, and expression of CSC markers CD44, SLC3A2, and MET were analyzed. For patients with eligible data on all parameters (n = 340), the risk of HDF following primary chemo-(C-)RT were analyzed by these biomarkers as a whole and stratified for p16-positive oropharynx (p16 + OPSCC) vs p16-negative (p16-) tumors (oral cavity, p16- oropharynx, hypopharynx and larynx). RESULTS: Higher risk of HDF was seen for patients with larger primary and nodal volume (>25 cm3, Hazard Ratio (HR): 3.00 [95 % CI: 1.73-5.18]), high SLC3A2 (HR: 2.99 [1.28-6.99]), CD44 (>30 % positive, HR: 2.29 [1.05-5.00]), and p16- tumors (HR: 2.53 [1.05-6.11]). p16- tumors had a higher CSC marker expression than p16 + OPSCC. The factors associated with the highest risk of HDF were larger volume (HR: 3.29 [1.79-6.04]) for p16- tumors (n = 178) and high SLC3A2 (HR: 6.19 [1.58-24.23]) for p16 + OPSCC (n = 162). CONCLUSION: Tumor volume, p16, and CSC markers are potential biomarkers for HDF for patients with HNSCC treated with (C-)RT. Lower expression of CSC in p16 + OPSCC may contribute to better tumor control.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Papillomavirus Infections , Humans , Squamous Cell Carcinoma of Head and Neck/metabolism , Prognosis , Carcinoma, Squamous Cell/radiotherapy , Tumor Burden , Head and Neck Neoplasms/metabolism , Hypoxia/metabolism , Biomarkers , Neoplastic Stem Cells/pathology , Papillomavirus Infections/metabolism , Cyclin-Dependent Kinase Inhibitor p16 , Biomarkers, Tumor/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL