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Due to an increasing awareness of the potential hazardousness of air pollutants, new laws, rules and guidelines have recently been implemented globally. In this respect, numerous studies have addressed traffic-related exposure to particulate matter using stationary technology so far. By contrast, only few studies used the advanced technology of mobile exposure analysis. The Mobile Air Quality Study (MAQS) addresses the issue of air pollutant exposure by combining advanced high-granularity spatial-temporal analysis with vehicle-mounted, person-mounted and roadside sensors. The MAQS-platform will be used by international collaborators in order 1) to assess air pollutant exposure in relation to road structure, 2) to assess air pollutant exposure in relation to traffic density, 3) to assess air pollutant exposure in relation to weather conditions, 4) to compare exposure within vehicles between front and back seat (children) positions, and 5) to evaluate "traffic zone"- exposure in relation to non-"traffic zone"-exposure. Primarily, the MAQS-platform will focus on particulate matter. With the establishment of advanced mobile analysis tools, it is planed to extend the analysis to other pollutants including including NO2, SO2, nanoparticles, and ozone.
The COVID-19 pandemic has caused strains on health systems worldwide disrupting routine hospital services for all non-COVID patients. Within this retrospective study, we analyzed inpatient hospital admissions across 18 German university hospitals during the 2020 lockdown period compared to 2018. Patients admitted to hospital between January 1 and May 31, 2020 and the corresponding periods in 2018 and 2019 were included in this study. Data derived from electronic health records were collected and analyzed using the data integration center infrastructure implemented in the university hospitals that are part of the four consortia funded by the German Medical Informatics Initiative. Admissions were grouped and counted by ICD 10 chapters and specific reasons for treatment at each site. Pooled aggregated data were centrally analyzed with descriptive statistics to compare absolute and relative differences between time periods of different years. The results illustrate how care process adoptions depended on the COVID-19 epidemiological situation and the criticality of the disease. Overall inpatient hospital admissions decreased by 35% in weeks 1 to 4 and by 30.3% in weeks 5 to 8 after the lockdown announcement compared to 2018. Even hospital admissions for critical care conditions such as malignant cancer treatments were reduced. We also noted a high reduction of emergency admissions such as myocardial infarction (38.7%), whereas the reduction in stroke admissions was smaller (19.6%). In contrast, we observed a considerable reduction in admissions for non-critical clinical situations, such as hysterectomies for benign tumors (78.8%) and hip replacements due to arthrosis (82.4%). In summary, our study shows that the university hospital admission rates in Germany were substantially reduced following the national COVID-19 lockdown. These included critical care or emergency conditions in which deferral is expected to impair clinical outcomes. Future studies are needed to delineate how appropriate medical care of critically ill patients can be maintained during a pandemic.
Men and women differ substantially regarding height, weight, and body fat. Interestingly, previous work detecting genetic effects for waist-to-hip ratio, to assess body fat distribution, has found that many of these showed sex-differences. However, systematic searches for sex-differences in genetic effects have not yet been conducted. Therefore, we undertook a genome-wide search for sexually dimorphic genetic effects for anthropometric traits including 133,723 individuals in a large meta-analysis and followed promising variants in further 137,052 individuals, including a total of 94 studies. We identified seven loci with significant sex-difference including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were significant in women, but not in men. Of interest is that sex-difference was only observed for waist phenotypes, but not for height or body-mass-index. We found no evidence for sex-differences with opposite effect direction for men and women. The PPARG locus is of specific interest due to its link to diabetes genetics and therapy. Our findings demonstrate the importance of investigating sex differences, which may lead to a better understanding of disease mechanisms with a potential relevance to treatment options.
Background: Tobacco is a leading environmental factor in the initiation of respiratory diseases and causes chronic obstructive pulmonary disease (COPD). Suppressor of cytokine signaling (SOCS) family members are involved in the pathogenesis of many inflammatory diseases and SOCS-3 has been shown to play an important role in the regulation, onset and maintenance of airway allergic inflammation indicating that SOCS-3 displays a potential therapeutic target for anti-inflammatory respiratory drugs development. Since chronic obstructive pulmonary disease (COPD) is also characterized by inflammatory changes and airflow limitation, the present study assessed the transcriptional expression of SOCS-3 in COPD.
Methods: Real-time PCR was performed to assess quantitative changes in bronchial biopsies of COPD patients in comparison to unaffected controls.
Results: SOCS-3 was significantly down-regulated in COPD at the transcriptional level while SOCS-4 and SOCS-5 displayed no change.
Conclusions: It can be concluded that the presently observed inhibition of SOCS-3 mRNA expression may be related to the dysbalance of cytokine signaling observed in COPD.
Background: Models of isolated and perfused kidneys are used to study the effects of drugs, hazardous or toxic substances on renal functions. Since physiological and morphological parameters of small laboratory animal kidneys are difficult to compare to human renal parameters, porcine kidney perfusion models have been developed to simulate closer conditions to the human situation, but exact values of renal parameters for different collection and perfusion conditions have not been reported so far. If the organs could be used out of regular slaughtering processes animal experiments may be avoided.
Methods: To assess renal perfusion quality, we analyzed different perfusion settings in a standardized model of porcine kidney hemoperfusion with organs collected in the operating theatre (OP: groups A-D) or in a public abattoir (SLA: group E) and compared the data to in vivo measurements in living animals (CON). Experimental groups had defined preservation periods (0, 2 and 24 hrs), one with additional albumin in the perfusate (C) for edema reduction.
Results: Varying perfusion settings resulted in different functional values (mean +/- SD): blood flow (RBF [ml/min*100 g]: (A) 339.9 +/- 61.1; (C) 244.5 +/- 53.5; (D) 92.8 +/- 25.8; (E) 153.8 +/- 41.5); glomerular filtration (GFR [ml/min*100 g]: (CON) 76.1 +/- 6.2; (A) 59.2 +/- 13.9; (C) 25.0 +/- 10.6; (D) 1.6 +/- 1.3; (E) 16.3 +/- 8.2); fractional sodium reabsorption (RFNa [%] (CON) 99.8 +/- 0.1; (A) 82.3 +/- 8.1; (C) 86.8 +/- 10.3; (D) 38.4 +/- 24.5; (E) 88.7 +/- 5.8). Additionally the tubular coupling-ratio of Na-reabsorption/O2-consumption was determined (TNa/O2-cons [mmol-Na/mmol- O2] (CON) 30.1; (A) 42.0, (C) 80.6; (D) 17.4; (E) 23.8), exhibiting OP and SLA organs with comparable results.
Conclusion: In the present study functional values for isolated kidneys with different perfusion settings were determined to assess organ perfusion quality. It can be summarized that the hemoperfused porcine kidney can serve as a biological model with acceptable approximation to in vivo renal physiology, also if the organs originate from usual slaughtering processes.
Background: Severe allergic reactions during rush-specific immunotherapy (Rush-SIT) may occur in the treatment of hymenoptera sting allergy. The objective of the present study was to examine the characteristics of allergic reactions during Rush-SIT in a cohort of patients with allergy towards hymenoptera venom in the mediterranean population of Albania.
Methods: A retrospective study was performed using the clinical reports of 37 patients with venom of bee (apinae), wasp (vespidae, subfamily vespinae) or paperwasp (vespidae, subfamily polistinae) allergy treated with Rush-SIT between 1987 and 1996. After hymenoptera sting allergy diagnosis according to anamnesis and intracutaneous tests the patient were treated with Rush-SIT. The protocol lasted 3 - 4 d with an increase in the concentration from 0.01 microg/ml to 100 microg/ml. Anaphylactic reactions were classified according to the Mueller-classification.
Results: The frequency of reactions during Rush-SIT for bee-venom was 4.7% and for wasp-venom was 1.5% (p < 0.01). The mean frequency of reactions of Mueller grade II for the bee-venom Rush-SIT patients during the first 4 d (= 26 injections) was 0.73 and for the wasp-venom Rush-SIT patients 0.15. No patient experienced a third-degree reaction. 94.6% of the patient supported an end dose of 100 microg.
Conclusions: Rush-SIT is a reliable method for the treatment of anaphylactic reactions to hymenoptera venom even in less developed countries. Bee-venom Rush-SIT was found to cause higher numbers allergic reactions than wasp or paperwasp Rush-SIT.
The sphingolipid sphingosine‐1‐phosphate (S1P) fulfills distinct functions in immune cell biology via binding to five G protein‐coupled receptors. The immune cell‐specific sphingosine‐1‐phosphate receptor 4 (S1pr4) was connected to the generation of IL‐17‐producing T cells through regulation of cytokine production in innate immune cells. Therefore, we explored whether S1pr4 affected imiquimod‐induced murine psoriasis via regulation of IL‐17 production. We did not observe altered IL‐17 production, although psoriasis severity was reduced in S1pr4‐deficient mice. Instead, ablation of S1pr4 attenuated the production of CCL2, IL‐6, and CXCL1 and subsequently reduced the number of infiltrating monocytes and granulocytes. A connection between S1pr4, CCL2, and Mϕ infiltration was also observed in Zymosan‐A induced peritonitis. Boyden chamber migration assays functionally linked reduced CCL2 production in murine skin and attenuated monocyte migration when S1pr4 was lacking. Mechanistically, S1pr4 signaling synergized with TLR signaling in resident Mϕs to produce CCL2, likely via the NF‐κB pathway. We propose that S1pr4 activation enhances TLR response of resident Mϕs to increase CCL2 production, which attracts further Mϕs. Thus, S1pr4 may be a target to reduce perpetuating inflammatory responses.
Hintergrund
In Anbetracht ihres bedeutenden Potenzials zur Verbesserung der medizinischen Versorgung wird Telemedizin weiterhin zu wenig genutzt. Trotz einiger erfolgreicher Pilotprojekte in den vergangenen Jahren ist insbesondere über die Hindernisse der Etablierung und Verstetigung von Telemedizin wenig bekannt. Diese Studie hatte das Ziel, die Einstellung niedergelassener Neurologen hinsichtlich der Nutzung von Telemedizin in der Epileptologie und resultierende Hinderungsgründe zu verstehen. Gleichzeitig werden mögliche Lösungsansätze präsentiert.
Methoden
Mithilfe eines individuell erstellten 14-Item-Fragebogens befragten wir prospektiv alle Neurologen, die zuvor die Teilnahme an einem transregionalen Telemedizinpilotprojekt im Bereich der Epileptologie abgelehnt oder keine Rückmeldung gegeben hatten, zu Gründen für und gegen den generellen Einsatz von bzw. die Teilnahme an Telemedizin.
Ergebnisse
Von 58 kontaktierten Neurologen antworteten 33 (57 %). Die häufigsten Gründe für die fehlende Nutzung der Telemedizin waren ein vermuteter Zeitmangel oder ein vermuteter zu großer organisatorischer Aufwand (49 %). Zudem wurden Bedenken bezüglich der technischen Ausstattung (30 %) und eine Präferenz für alternative Wege der intersektoralen Kommunikation (30 %) angegeben. Befürchtete Probleme in Bezug auf die Kostenerstattung für telemedizinische Leistungen waren für 27 % ein Hindernis. Neurologen in ländlichen Gebieten waren signifikant häufiger bereit, zunächst eine telemedizinische Konsultation anzufordern, bevor sie eine Überweisung ausstellen (p = 0,006).
Schlussfolgerungen
Die flächendeckende Etablierung von Telemedizinstrukturen ist immer noch durch Hindernisse erschwert, die meist im organisatorischen Bereich liegen. Die bestehenden Herausforderungen im Gesundheitswesen in ländlichen Gebieten sind eine besondere Chance für die Implementierung von Telemedizin. Die meisten Probleme der Telemedizin können gelöst werden, sollten aber bereits bei der Konzeptionierung von Projekten mitbedacht werden, um ihre Verstetigung zu erleichtern.
Alcoholism is one of the leading and increasingly prevalent reasons of liver associated morbidity and mortality worldwide. Alcoholic hepatitis (AH) constitutes a severe disease with currently no satisfying treatment options. Lipoxin A4 (LXA4), a 15-lipoxygenase (ALOX15)-dependent lipid mediator involved in resolution of inflammation, showed promising pre-clinical results in the therapy of several inflammatory diseases. Since inflammation is a main driver of disease progression in alcoholic hepatitis, we investigated the impact of endogenous ALOX15-dependent lipid mediators and exogenously applied LXA4 on AH development. A mouse model for alcoholic steatohepatitis (NIAAA model) was tested in Alox12/15+/+ and Alox12/15−/− mice, with or without supplementation of LXA4. Absence of Alox12/15 aggravated parameters of liver disease, increased hepatic immune cell infiltration in AH, and elevated systemic neutrophils as a marker for systemic inflammation. Interestingly, i.p. injections of LXA4 significantly lowered transaminase levels only in Alox12/15−/− mice and reduced hepatic immune cell infiltration as well as systemic inflammatory cytokine expression in both genotypes, even though steatosis progressed. Thus, while LXA4 injection attenuated selected parameters of disease progression in Alox12/15−/− mice, its beneficial impact on immunity was also apparent in Alox12/15+/+ mice. In conclusion, pro-resolving lipid mediators may be beneficial to reduce inflammation in alcoholic hepatitis.
In Eurotransplant kidney allocation system (ETKAS), candidates can be considered unlimitedly for repeated re‐transplantation. Data on outcome and benefit are indeterminate. We performed a retrospective 15‐year patient and graft outcome data analysis from 1464 recipients of a third or fourth or higher sequential deceased donor renal transplantation (DDRT) from 42 transplant centers. Repeated re‐DDRT recipients were younger (mean 43.0 vs. 50.2 years) compared to first DDRT recipients. They received grafts with more favorable HLA matches (89.0% vs. 84.5%) but thereby no statistically significant improvement of patient and graft outcome was found as comparatively demonstrated in 1st DDRT. In the multivariate modeling accounting for confounding factors, mortality and graft loss after 3rd and ≥4th DDRT (P < 0.001 each) and death with functioning graft (DwFG) after 3rd DDRT (P = 0.001) were higher as compared to 1st DDRT. The incidence of primary nonfunction (PNF) was also significantly higher in re‐DDRT (12.7%) than in 1st DDRT (7.1%; P < 0.001). Facing organ shortage, increasing waiting time, and considerable mortality on dialysis, we question the current policy of repeated re‐DDRT. The data from this survey propose better HLA matching in first DDRT and second DDRT and careful selection of candidates, especially for ≥4th DDRT.
Consensus on definition and severity grading of lymphatic complications after kidney transplantation
(2020)
Background: The incidence of lymphatic complications after kidney transplantation varies considerably in the literature. This is partly because a universally accepted definition has not been established. This study aimed to propose an acceptable definition and severity grading system for lymphatic complications based on their management strategy.
Methods: Relevant literature published in MEDLINE and Web of Science was searched systematically. A consensus for definition and a severity grading was then sought between 20 high-volume transplant centres.
Results: Lymphorrhoea/lymphocele was defined in 32 of 87 included studies. Sixty-three articles explained how lymphatic complications were managed, but none graded their severity. The proposed definition of lymphorrhoea was leakage of more than 50 ml fluid (not urine, blood or pus) per day from the drain, or the drain site after removal of the drain, for more than 1 week after kidney transplantation. The proposed definition of lymphocele was a fluid collection of any size near to the transplanted kidney, after urinoma, haematoma and abscess have been excluded. Grade A lymphatic complications have a minor and/or non-invasive impact on the clinical management of the patient; grade B complications require non-surgical intervention; and grade C complications require invasive surgical intervention.
Conclusion: A clear definition and severity grading for lymphatic complications after kidney transplantation was agreed. The proposed definitions should allow better comparisons between studies.
Apheresis therapies for NMOSD attacks : a retrospective study of 207 therapeutic interventions
(2018)
Objective: To analyze whether 1 of the 2 apheresis techniques, therapeutic plasma exchange (PE) or immunoadsorption (IA), is superior in treating neuromyelitis optica spectrum disorder (NMOSD) attacks and to identify predictive factors for complete remission (CR).
Methods: This retrospective cohort study was based on the registry of the German Neuromyelitis Optica Study Group, a nationwide network established in 2008. It recruited patients with neuromyelitis optica diagnosed according to the 2006 Wingerchuk criteria or with aquaporin-4 (AQP4-ab)-antibody–seropositive NMOSD treated at 6 regional hospitals and 16 tertiary referral centers until March 2013. Besides descriptive data analysis of patient and attack characteristics, generalized estimation equation (GEE) analyses were applied to compare the effectiveness of the 2 apheresis techniques. A GEE model was generated to assess predictors of outcome.
Results: Two hundred and seven attacks in 105 patients (87% AQP4-ab-antibody seropositive) were treated with at least 1 apheresis therapy. Neither PE nor IA was proven superior in the therapy of NMOSD attacks. CR was only achieved with early apheresis therapy. Strong predictors for CR were the use of apheresis therapy as first-line therapy (OR 12.27, 95% CI: 1.04–144.91, p = 0.047), time from onset of attack to start of therapy in days (OR 0.94, 95% CI: 0.89–0.99, p = 0.014), the presence of AQP4-ab-antibodies (OR 33.34, 95% CI: 1.76–631.17, p = 0.019), and monofocal attack manifestation (OR 4.71, 95% CI: 1.03–21.62, p = 0.046).
Conclusions: Our findings suggest early use of an apheresis therapy in NMOSD attacks, particularly in AQP4-ab-seropositive patients. No superiority was shown for one of the 2 apheresis techniques.
Classification of evidence: This study provides Class IV evidence that for patients with NMOSD, neither PE nor IA is superior in the treatment of attacks.
Background: Conditions during blood product storage and transportation should maintain quality. The aim of this in vitro study was to investigate the effect of interruption of agitation, temporary cooling (TC), and pneumatic tube system transportation (PTST) on the aggregation ability (AA) and mitochondrial function (MF) of platelet concentrates (PC).
Study Design and Methods: A PC was divided equally into four subunits and then allocated to four test groups. The control group (I) was stored as recommended (continuous agitation, 22 ± 2°C) for 4 days. The test groups were stored without agitation (II), stored as recommended, albeit 4°C for 60 minutes on day (d)2 (III) and PTST (IV). Aggregometry was measured using Multiplate (RocheAG; ADPtest, ASPItest, TRAPtest, COLtest) and MF using Oxygraph‐2k (Oroboros Instruments). The basal and maximum mitochondrial respiratory rate (MMRR) were determined. AA and MF were measured daily in I and II and AA in III and IV on d2 after TC/PTST. Statistical analysis was performed using tests for matched observations.
Results: Eleven PCs were used. TRAP‐6 induced AA was significantly lower in II when compared to I on d4 (P = 0.015*). In III the ASPItest was significantly lower (P = 0.032*). IV showed no significant differences. The basal and MMRR were significantly reduced over 4 days in I and II (for both rates in both groups: P = <0.0001*). No significant differences occurred on d4 (P = 0.495).
Conclusion: Our results indicate that ex vivo AA and MF of PCs are unaffected, even in no‐ideal storage and transport circumstances with respect to agitation, temperature, and force.
Aims: Patients with aortic stenosis (AS) may have concomitant heart failure (HF) that determines prognosis despite successful transcatheter aortic valve implantation (TAVI). We compared outcomes of TAVI patients with low stroke volume index (SVI) ≤35 ml/m2 body surface area in different HF classes.
Methods and results: Patients treated by transfemoral TAVI at our center (n = 1822) were classified as 1) ‘HF with preserved ejection fraction (EF)’ (HFpEF, EF ≥50%), 2) ‘HF with mid-range EF’ (HFmrEF, EF 40–49%), or 3) ‘HF with reduced EF’ (HFrEF, EF <40%). Patients with SVI >35 ml/m2 served as controls. The prevalence of cardiovascular disease and symptoms increased stepwise from controls (n = 968) to patients with HFpEF (n = 591), HFmrEF (n = 97), and HFrEF (n = 166). Mortality tended to be highest in HFrEF patients 30 days post-procedure, and it became significant after one year: 10.2% (controls), 13.5% (HFpEF), 13.4% (HFmrEF), and 23.5% (HFrEF). However, symptomatic improvement in survivors of all groups was achieved in the majority of patients without differences among groups.
Conclusions: Patients with AS and HF benefit from TAVI with respect to symptom alleviation. TAVI in patients with HFpEF and HFmrEF led to an identical, favorable post-procedural prognosis that was significantly better than that of patients with HFrEF, which remains a high-risk population.
The Kinase Chemogenomic Set (KCGS): an open science resource for kinase vulnerability identification
(2021)
We describe the assembly and annotation of a chemogenomic set of protein kinase inhibitors as an open science resource for studying kinase biology. The set only includes inhibitors that show potent kinase inhibition and a narrow spectrum of activity when screened across a large panel of kinase biochemical assays. Currently, the set contains 187 inhibitors that cover 215 human kinases. The kinase chemogenomic set (KCGS), current Version 1.0, is the most highly annotated set of selective kinase inhibitors available to researchers for use in cell-based screens.
The Kinase Chemogenomic Set (KCGS): An open science resource for kinase vulnerability identification
(2019)
We describe the assembly and annotation of a chemogenomic set of protein kinase inhibitors as an open science resource for studying kinase biology. The set only includes inhibitors that show potent kinase inhibition and a narrow spectrum of activity when screened across a large panel of kinase biochemical assays. Currently, the set contains 187 inhibitors that cover 215 human kinases. The kinase chemogenomic set (KCGS) is the most highly annotated set of selective kinase inhibitors available to researchers for use in cell-based screens.
Background
Cytochrome-P450 (CYP450) epoxygenases metabolise arachidonic acid (AA) into four different biologically active epoxyeicosatrienoic acid (EET) regioisomers. Three of the EETs (i.e., 8,9-, 11,12- and 14,15-EET) are rapidly hydrolysed by the enzyme soluble epoxide hydrolase (sEH). Here, we investigated the role of sEH in nociceptive processing during peripheral inflammation.
Results
In dorsal root ganglia (DRG), we found that sEH is expressed in medium and large diameter neurofilament 200-positive neurons. Isolated DRG-neurons from sEH-/- mice showed higher EET and lower DHET levels. Upon AA stimulation, the largest changes in EET levels occurred in culture media, indicating both that cell associated EET concentrations quickly reach saturation and EET-hydrolyzing activity mostly effects extracellular EET signaling. In vivo, DRGs from sEH-deficient mice exhibited elevated 8,9-, 11,12- and 14,15-EET-levels. Interestingly, EET levels did not increase at the site of zymosan-induced inflammation. Cellular imaging experiments revealed direct calcium flux responses to 8,9-EET in a subpopulation of nociceptors. In addition, 8,9-EET sensitized AITC-induced calcium increases in DRG neurons and AITC-induced calcitonin gene related peptide (CGRP) release from sciatic nerve axons, indicating that 8,9-EET sensitizes TRPA1-expressing neurons, which are known to contribute to mechanical hyperalgesia. Supporting this, sEH-/- mice showed increased nociceptive responses to mechanical stimulation during zymosan-induced inflammation and 8,9-EET injection reduced mechanical thresholds in naive mice.
Conclusion
Our results show that the sEH can regulate mechanical hyperalgesia during inflammation by inactivating 8,9-EET, which sensitizes TRPA1-expressing nociceptors. Therefore we suggest that influencing the CYP450 pathway, which is actually highly considered to treat cardiovascular diseases, may cause pain side effects.
Background: Glucose metabolism in the tumor-microenvironment is a fundamental hallmark for tumor growth and intervention therein remains an attractive option for anti-tumor therapy. Whether tumor-derived factors such as microRNAs (miRs) regulate glucose metabolism in stromal cells, especially in tumor-associated macrophages (TAMs), to hijack them for trophic support, remains elusive.
Methods: Ago-RIP-Seq identified macrophage lactate dehydrogenase B (LDHB) as a target of tumor-derived miR-375 in both 2D/3D cocultures and in murine TAMs from a xenograft mouse model. The prognostic value was analyzed by ISH and multiplex IHC of breast cancer patient tissues. Functional consequences of the miR-375-LDHB axis in TAMs were investigated upon mimic/antagomir treatment by live metabolic flux assays, GC/MS, qPCR, Western blot, lentiviral knockdown and FACS. The therapeutic potential of a combinatorial miR-375-decoy/simvastatin treatment was validated by live cell imaging.
Results: Macrophage LDHB decreased in murine and human breast carcinoma. LDHB downregulation increase aerobic glycolysis and lactagenesis in TAMs in response to tumor-derived miR-375. Lactagenesis reduced fatty acid synthesis but activated SREBP2, which enhanced cholesterol biosynthesis in macrophages. LDHB downregulation skewed TAMs to function as a lactate and sterol/oxysterol source for the proliferation of tumor cells. Restoring of LDHB expression potentiated inhibitory effects of simvastatin on tumor cell proliferation.
Conclusion: Our findings identified a crucial role of LDHB in macrophages and established tumor-derived miR-375 as a novel regulator of macrophage metabolism in breast cancer, which might pave the way for strategies of combinatorial cancer cell/stroma cell interventions.
Background: Despite advances in treatment of patients with non-small cell lung cancer, carriers of certain genetic alterations are prone to failure. One such factor frequently mutated, is the tumor suppressor PTEN. These tumors are supposed to be more resistant to radiation, chemo- and immunotherapy.
Results: We demonstrate that loss of PTEN led to altered expression of transcriptional programs which directly regulate therapy resistance, resulting in establishment of radiation resistance. While PTEN-deficient tumor cells were not dependent on DNA-PK for IR resistance nor activated ATR during IR, they showed a significant dependence for the DNA damage kinase ATM. Pharmacologic inhibition of ATM, via KU-60019 and AZD1390 at non-toxic doses, restored and even synergized with IR in PTEN-deficient human and murine NSCLC cells as well in a multicellular organotypic ex vivo tumor model.
Conclusion: PTEN tumors are addicted to ATM to detect and repair radiation induced DNA damage. This creates an exploitable bottleneck. At least in cellulo and ex vivo we show that low concentration of ATM inhibitor is able to synergise with IR to treat PTEN-deficient tumors in genetically well-defined IR resistant lung cancer models.