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The multifunctional protein p21Cip1/CDKN1A (p21) is an important and universal Cdk-interacting protein. Recently, we have reported that p21 is involved in the regulation of the mitotic kinase Cdk1/cyclin B1 and critical for successful mitosis and cytokinesis. In the present work we show that S130 of p21 is phosphorylated by Cdk1/cyclin B1 during mitosis, which reduces p21’s stability and binding affinity to Cdk1/cyclin B1. Interfering with this phosphorylation results in extended mitotic duration and defective chromosome segregation, indicating that this regulation ensures proper mitotic progression. Given that p53, the major transcriptional activator of p21, is the most frequently mutated gene in human cancer and that deregulated Cdk1 associates with the development of different types of cancer, this work provides new insight into the understanding of how deregulated p21 contributes to chromosomal instability and oncogenesis.
Impact of Polo-like kinase 1 inhibitors on human adipose tissue-derived mesenchymal stem cells
(2016)
Polo-like kinase 1 (Plk1) has been established as one of the most promising targets for molecular anticancer intervention. In fact, various Plk1 inhibitors have been identified and characterized. While the data derived from the bench are prospective, the clinical outcomes are less encouraging by showing modest efficacy. One of the explanations for this discrepancy could be unintendedly targeting of non-malignant cells by Plk1 inhibitors. In this work, we have addressed the effect of Plk1 inhibition in adipose tissue-derived mesenchymal stem cells (ASCs). We show that both visceral and subcutaneous ASCs display monopolar spindles, reduced viability and strong apoptosis induction upon treatment with BI 2536 and BI 6727, the Plk1 kinase domain inhibitors, and with Poloxin, the regulatory Polo-box domain inhibitor. While Poloxin triggers quickly apoptosis, BI 2536 and BI 6727 result in mitotic arrest in ASCs. Importantly, survived ASCs exhibit DNA damage and a pronounced senescent phenotype. In addition, Plk1 inhibition impairs ASCs’ motility and homing ability. These results show that Plk1 inhibitors target slowly proliferating ASCs, an important population of anti-inflammation and immune modulation. The toxic effects on primary cells like ASCs could be partially responsible for the reported moderate antitumor activity in patients treated with Plk1 inhibitors.
Although the mechanistic target of rapamycin (mTOR) inhibitor, everolimus, has improved the outcome of patients with renal cell carcinoma (RCC), improvement is temporary due to the development of drug resistance. Since many patients encountering resistance turn to alternative/complementary treatment options, an investigation was initiated to evaluate whether the natural compound, sulforaphane (SFN), influences growth and invasive activity of everolimus-resistant (RCCres) compared to everolimus-sensitive (RCCpar) RCC cell lines in vitro. RCC cells were exposed to different concentrations of SFN and cell growth, cell proliferation, apoptosis, cell cycle, cell cycle regulating proteins, the mTOR-akt signaling axis, adhesion to human vascular endothelium and immobilized collagen, chemotactic activity, and influence on surface integrin receptor expression were investigated. SFN caused a significant reduction in both RCCres and RCCpar cell growth and proliferation, which correlated with an elevation in G2/M- and S-phase cells. SFN induced a marked decrease in the cell cycle activating proteins cdk1 and cyclin B and siRNA knock-down of cdk1 and cyclin B resulted in significantly diminished RCC cell growth. SFN also modulated adhesion and chemotaxis, which was associated with reduced expression of the integrin subtypes α5, α6, and β4. Distinct differences were seen in RCCres adhesion and chemotaxis (diminished by SFN) and RCCpar adhesion (enhanced by SFN) and chemotaxis (not influenced by SFN). Functional blocking of integrin subtypes demonstrated divergent action on RCC binding and invasion, depending on RCC cell sensitivity to everolimus. Therefore, SFN administration could hold potential for treating RCC patients with established resistance towards everolimus.
EUSOBI and 30 national breast radiology bodies support mammography for population-based screening, demonstrated to reduce breast cancer (BC) mortality and treatment impact. According to the International Agency for Research on Cancer, the reduction in mortality is 40 % for women aged 50–69 years taking up the invitation while the probability of false-positive needle biopsy is <1 % per round and overdiagnosis is only 1–10 % for a 20-year screening. Mortality reduction was also observed for the age groups 40–49 years and 70–74 years, although with “limited evidence”. Thus, we firstly recommend biennial screening mammography for average-risk women aged 50–69 years; extension up to 73 or 75 years, biennially, is a second priority, from 40–45 to 49 years, annually, a third priority. Screening with thermography or other optical tools as alternatives to mammography is discouraged. Preference should be given to population screening programmes on a territorial basis, with double reading. Adoption of digital mammography (not film-screen or phosphor-plate computer radiography) is a priority, which also improves sensitivity in dense breasts. Radiologists qualified as screening readers should be involved in programmes. Digital breast tomosynthesis is also set to become “routine mammography” in the screening setting in the next future. Dedicated pathways for high-risk women offering breast MRI according to national or international guidelines and recommendations are encouraged.
We assessed the prognostic value of hypoxia (carbonic anhydrase 9; CA9), vessel density (CD31), with macrophages (CD68) and B cells (CD20) that can interact and lead to immune suppression and disease progression using scanning and histological mapping of whole-mount FFPE pancreatectomy tissue sections from 141 primarily resectable pancreatic ductal adenocarcinoma (PDAC) samples treated with surgery and adjuvant chemotherapy. Their expression was correlated with clinicopathological characteristics, and overall survival (OS), progression-free survival (PFS), local progression-free survival (LPFS) and distant metastases free-survival (DMFS), also in the context of stroma density (haematoxylin-eosin) and activity (alpha-smooth muscle actin). The median OS was 21 months after a mean follow-up of 20 months (range, 2–69 months). The median tumor surface area positive for CA9 and CD31 was 7.8% and 8.1%, respectively. Although total expression of these markers lacked prognostic value in the entire cohort, nevertheless, high tumor compartment CD68 expression correlated with worse PFS (p = 0.033) and DMFS (p = 0.047). Also, high CD31 expression predicted for worse OS (p = 0.004), PFS (p = 0.008), LPFS (p = 0.014) and DMFS (p = 0.004) in patients with moderate density stroma. High stromal and peripheral compartment CD68 expression predicted for significantly worse outcome in patients with loose and moderate stroma density, respectively. Altogether, in contrast to the current notion, hypoxia levels in PDAC appear to be comparable to other malignancies. CD31 and CD68 constitute prognostic markers in patient subgroups that vary according to tumor compartment and stromal density. Our study provides important insight on the pathophysiology of PDAC and should be exploited for future treatments.
Background: Few studies have evaluated the impact of pre-treatment drug resistance (PDR) on response to combination antiretroviral treatment (cART) in children. The objective of this joint EuroCoord-CHAIN-EPPICC/PENTA project was to assess the prevalence of PDR mutations and their association with virological outcome in the first year of cART in children.
Methods: HIV-infected children <18 years initiating cART between 1998 and 2008 were included if having at least one genotypic resistance test prior to cART initiation. We used the World Health Organization 2009 resistance mutation list and Stanford algorithm to infer resistance to prescribed drugs. Time to virological failure (VF) was defined as the first of two consecutive HIV-RNA > 500 copies/mL after 6 months cART and was assessed by Cox proportional hazards models. All models were adjusted for baseline demographic, clinical, immunology and virology characteristics and calendar period of cART start and initial cART regimen.
Results: Of 476 children, 88 % were vertically infected. At cART initiation, median (interquartile range) age was 6.6 years (2.1–10.1), CD4 cell count 297 cells/mm3 (98–639), and HIV-RNA 5.2 log10copies/mL (4.7–5.7). Of 37 children (7.8 %, 95 % confidence interval (CI), 5.5–10.6) harboring a virus with ≥1 PDR mutations, 30 children had a virus resistant to ≥1 of the prescribed drugs. Overall, the cumulative Kaplan-Meier estimate for virological failure was 19.8 % (95 %CI, 16.4–23.9). Cumulative risk for VF tended to be higher among children harboring a virus with PDR and resistant to ≥1 drug prescribed than among those receiving fully active cART: 32.1 % (17.2–54.8) versus 19.4 % (15.9–23.6) (P = 0.095). In multivariable analysis, age was associated with a higher risk of VF with a 12 % reduced risk per additional year (HR 0.88; 95 %CI, 0.82–0.95; P < 0.001).
Conclusions: PDR was not significantly associated with a higher risk of VF in children in the first year of cART. The risk of VF decreased by 12 % per additional year at treatment initiation which may be due to fading of PDR mutations over time. Lack of appropriate formulations, in particular for the younger age group, may be an important determinant of virological failure.
Influence of the sFlt-1/PlGF ratio on clinical decision-making in women with suspected preeclampsia
(2016)
Objective: To evaluate the influence of the soluble fms-like tyrosine kinase 1/placental growth factor ratio in physicians’ decision making in pregnant women with signs and symptoms of preeclampsia in routine clinical practice.
Methods: A multicenter, prospective, open, non-interventional study enrolled pregnant women presenting with preeclampsia signs and symptoms in several European perinatal care centers. Before the soluble fms-like tyrosine kinase 1/placental growth factor ratio result was known, physicians documented intended clinical procedures using an iPad® application (data locked/time stamped). After the result was available, clinical decisions were confirmed or revised and documented. An independent adjudication committee evaluated the appropriateness of decisions based on maternal/fetal outcomes. Clinician decision making with regard to hospitalization was the primary outcome.
Results: In 16.9% of mothers (20/118) the hospitalization decision was changed after knowledge of the ratio. In 13 women (11.0%), the initial decision to hospitalize was changed to no hospitalization. In seven women (5.9%) the revised decision was hospitalization. All revised decisions were considered appropriate by the panel of adjudicators (McNemar test; p < 0.0001).
Conclusions: The use of the soluble fms-like tyrosine kinase 1/placental growth factor test influenced clinical decision making towards appropriate hospitalization in a considerable proportion of women with suspected preeclampsia. This is the first study to demonstrate the impact of angiogenic biomarkers on decision making in a routine clinical practice.
Background: Hemodynamic instability is frequent and outcome-relevant in critical illness. The understanding of complex hemodynamic disturbances and their monitoring and management plays an important role in treatment of intensive care patients. An increasing number of treatment recommendations and guidelines in intensive care medicine emphasize hemodynamic goals, which go beyond the measurement of blood pressures. Yet, it is not known to which extent the infrastructural prerequisites for extended hemodynamic monitoring are given in intensive care units (ICUs) and how hemodynamic management is performed in clinical practice. Further, it is still unclear which factors trigger the use of extended hemodynamic monitoring.
Methods: In this multicenter, 1-day (November 7, 2013, and the preceding 24 h) cross-sectional study, we retrieved data on patient monitoring from ICUs in Germany, Austria, and Switzerland by means of a web-based case report form. One hundred and sixty-one intensive care units contributed detailed information on availability of hemodynamic monitoring. In addition, detailed information on hemodynamic monitoring of 1789 patients that were treated on due date was collected, and independent factors triggering the use of extended hemodynamic monitoring were identified by multivariate analysis.
Results: Besides basic monitoring with electrocardiography (ECG), pulse oximetry, and blood pressure monitoring, the majority of patients received invasive arterial (77.9 %) and central venous catheterization (55.2 %). All over, additional extended hemodynamic monitoring for assessment of cardiac output was only performed in 12.3 % of patients, while echocardiographic examination was used in only 1.9 %. The strongest independent predictors for the use of extended hemodynamic monitoring of any kind were mechanical ventilation, the need for catecholamine therapy, and treatment backed by protocols. In 71.6 % of patients in whom extended hemodynamic monitoring was added during the study period, this extension led to changes in treatment.
Conclusions: Extended hemodynamic monitoring, which goes beyond the measurement of blood pressures, to date plays a minor role in the surveillance of critically ill patients in German, Austrian, and Swiss ICUs. This includes also consensus-based recommended diagnostic and monitoring applications, such as echocardiography and cardiac output monitoring. Mechanical ventilation, the use of catecholamines, and treatment backed by protocol could be identified as factors independently associated with higher use of extended hemodynamic monitoring.
Resistance formation after initial therapy response (acquired resistance) is common in high-risk neuroblastoma patients. YM155 is a drug candidate that was introduced as a survivin suppressant. This mechanism was later challenged, and DNA damage induction and Mcl-1 depletion were suggested instead. Here we investigated the efficacy and mechanism of action of YM155 in neuroblastoma cells with acquired drug resistance. The efficacy of YM155 was determined in neuroblastoma cell lines and their sublines with acquired resistance to clinically relevant drugs. Survivin levels, Mcl-1 levels, and DNA damage formation were determined in response to YM155. RNAi-mediated depletion of survivin, Mcl-1, and p53 was performed to investigate their roles during YM155 treatment. Clinical YM155 concentrations affected the viability of drug-resistant neuroblastoma cells through survivin depletion and p53 activation. MDM2 inhibitor-induced p53 activation further enhanced YM155 activity. Loss of p53 function generally affected anti-neuroblastoma approaches targeting survivin. Upregulation of ABCB1 (causes YM155 efflux) and downregulation of SLC35F2 (causes YM155 uptake) mediated YM155-specific resistance. YM155-adapted cells displayed increased ABCB1 levels, decreased SLC35F2 levels, and a p53 mutation. YM155-adapted neuroblastoma cells were also characterized by decreased sensitivity to RNAi-mediated survivin depletion, further confirming survivin as a critical YM155 target in neuroblastoma. In conclusion, YM155 targets survivin in neuroblastoma. Furthermore, survivin is a promising therapeutic target for p53 wild-type neuroblastomas after resistance acquisition (neuroblastomas are rarely p53-mutated), potentially in combination with p53 activators. In addition, we show that the adaptation of cancer cells to molecular-targeted anticancer drugs is an effective strategy to elucidate a drug’s mechanism of action.
Background: Community acquired viruses (CRVs) may cause severe disease in cancer patients. Thus, efforts should be made to diagnose CRV rapidly and manage CRV infections accordingly.
Methods: A panel of 18 clinicians from the Infectious Diseases Working Party of the German Society for Haematology and Medical Oncology have convened to assess the available literature and provide recommendations on the management of CRV infections including influenza, respiratory syncytial virus, parainfluenza virus, human metapneumovirus and adenovirus.
Results: CRV infections in cancer patients may lead to pneumonia in approximately 30% of the cases, with an associated mortality of around 25%. For diagnosis of a CRV infection, combined nasal/throat swabs or washes/aspirates give the best results and nucleic acid amplification based-techniques (NAT) should be used to detect the pathogen. Hand hygiene, contact isolation and face masks have been shown to be of benefit as general infection management. Causal treatment can be given for influenza, using a neuraminidase inhibitor, and respiratory syncytial virus, using ribavirin in addition to intravenous immunoglobulins. Ribavirin has also been used to treat parainfluenza virus and human metapneumovirus, but data are inconclusive in this setting. Cidofovir is used to treat adenovirus pneumonitis.
Conclusions: CRV infections may pose a vital threat to patients with underlying malignancy. This guideline provides information on diagnosis and treatment to improve the outcome.
Background: Shortening duration of peginterferon-based HCV treatment reduces associated burden for patients. Primary objectives of this study were to assess the efficacy against the minimally acceptable response rate 12 weeks post-treatment (SVR12) and safety of simeprevir plus PR in treatment-naïve HCV GT1 patients treated for 12 weeks. Additional objectives included the investigation of potential associations of rapid viral response and baseline factors with SVR12.
Methods: In this Phase III, open-label study in treatment-naïve HCV GT1 patients with F0–F2 fibrosis, patients with HCV-RNA <25 IU/mL (detectable/undetectable) at Week 2, and undetectable HCV-RNA at Weeks 4 and 8, stopped all treatment at Week 12. All other patients continued PR for a further 12 weeks. Baseline factors significantly associated with SVR12 were identified through logistic regression.
Results: Of 163 patients who participated in the study, 123 (75%) qualified for 12-week treatment; of these, 81 (66%) achieved SVR12. Baseline factors positively associated with SVR12 rates in patients receiving the 12-week regimen were: IL28B CC genotype: (94% SVR12); HCV RNA ≤800,000 IU/mL (82%); F0–F1 fibrosis (74%). Among all 163 patients, 94% experienced ≥1 adverse event (AE), 4% a serious AE, and 2.5% discontinued due to an AE. Reduced impairment in patient-reported outcomes was observed in the 12-week vs >12-week regimen.
Conclusions: Overall SVR12 rate (66%) was below the target of 80%, indicating that shortening of treatment with simeprevir plus PR to 12 weeks based on very early response is not effective. However, baseline factors associated with higher SVR12 rates were identified. Therefore, while Week 2 response alone is insufficient to predict efficacy, GT1 patients with favourable baseline factors may benefit from a shortened simeprevir plus PR regimen.
Trial Registration: ClinicalTrials.gov NCT01846832
Background: Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. Growing evidence indicates that tumor-initiating cells (TICs) are responsible for tumor growth and progression. Conventional chemotherapeutics do not sufficiently eliminate TICs, leading to tumor relapse. We aimed to gain insight into TIC biology by comparing the transcriptome of primary TIC cultures and their normal stem cell counterparts to uncover expression differences.
Methods: We established colonosphere cultures derived from the resection of paired specimens of primary tumor and normal mucosa in patients with CRC. These colonospheres, enriched for TICs, were used for differential transcriptome analyses to detect new targets for a TIC-directed therapy. Effects of target inhibition on CRC cells were studied in vitro and in vivo.
Results: Pathway analysis of the regulated genes showed enrichment of genes central to PI3K/AKT and Wnt-signaling. We identified CD133 as a marker for a more aggressive CRC subpopulation enriched with TICs in SW480 CRC cells in an in vivo cancer model. Treatment of CRC cells with the selective AKT inhibitor MK-2206 caused a decrease in cell proliferation, particularly in the TIC fraction, resulting in a significant reduction of the stemness capacity to form colonospheres in vitro and to initiate tumor formation in vivo. Consequently, MK-2206 treatment of mice with established xenograft tumors exhibited a significant deceleration of tumor progression. Primary patient-derived tumorsphere growth was significantly inhibited by MK-2206.
Conclusion: This study reveals that AKT signaling is critical for TIC proliferation and can be efficiently targeted by MK-2206 representing a preclinical therapeutic strategy to repress colorectal TICs.
Monitoring of minimal residual disease (MRD) or chimerism may help guide pre-emptive immunotherapy (IT) with a view to preventing relapse in childhood acute lymphoblastic leukemia (ALL) after transplantation. Patients with ALL who consecutively underwent transplantation in Frankfurt/Main, Germany between January 1, 2005 and July 1, 2014 were included in this retrospective study. Chimerism monitoring was performed in all, and MRD assessment was performed in 58 of 89 patients. IT was guided in 19 of 24 patients with mixed chimerism (MC) and MRD and by MRD only in another 4 patients with complete chimerism (CC). The 3-year probabilities of event-free survival (EFS) were .69 ± .06 for the cohort without IT and .69 ± .10 for IT patients. Incidences of relapse (CIR) and treatment-related mortality (CITRM) were equally distributed between both cohorts (without IT: 3-year CIR, .21 ± .05, 3-year CITRM, .10 ± .04; IT patients: 3-year CIR, .18 ± .09, 3-year CITRM .13 ± .07). Accordingly, 3-year EFS and 3-year CIR were similar in CC and MC patients with IT, whereas MC patients without IT experienced relapse. IT was neither associated with an enhanced immune recovery nor an increased risk for acute graft-versus-host disease. Relapse prevention by IT in patients at risk may lead to the same favorable outcome as found in CC and MRD-negative-patients. This underlines the importance of excellent MRD and chimerism monitoring after transplantation as the basis for IT to improve survival in childhood ALL.
Infant acute leukemia still has a poor prognosis, and allogeneic hematopoietic stem cell transplantation is indicated in selected patients. Umbilical cord blood (UCB) is an attractive cell source for this population because of the low risk of chronic graft-versus-host disease (GVHD), the strong graft-versus-leukemia effect, and prompt donor availability. This retrospective, registry-based study reported UCB transplantation (UCBT) outcomes in 252 children with acute lymphoblastic leukemia (ALL; n = 157) or acute myelogenous leukemia (AML; n = 95) diagnosed before 1 year of age who received a single-unit UCBT after myeloablative conditioning between 1996 and 2012 in European Society for Blood and Marrow Transplantation centers. Median age at UCBT was 1.1 years, and median follow-up was 42 months. Most patients (57%) received a graft with 1 HLA disparity and were transplanted in first complete remission (CR; 55%). Cumulative incidence function (CIF) of day 100 acute GVHD (grades II to IV) was 40% ± 3% and of 4-year chronic GVHD was 13% ± 2%. CIF of 1-year transplant-related mortality was 23% ± 3% and of 4-year relapse was 27% ± 3%. Leukemia-free-survival (LFS) at 4 years was 50% ± 3%; it was 40% and 66% for those transplanted for ALL and AML, respectively (P = .001). LFS was better for patients transplanted in first CR, regardless of diagnosis. In multivariate model, diagnosis of ALL (P = .001), advanced disease status at UCBT (<.001), age at diagnosis younger than 3 months (P = .012), and date of transplant before 2004 were independently associated with worse LFS. UCBT is a suitable option for patients diagnosed with infant acute leukemia who achieve CR. In this cohort, patients with AML had better survival than those with ALL.
Natural Killer (NK) cells are active against Aspergillus fumigatus, which in turn is able to impair the host defense. Unfortunately, little is known on the mutual interaction of NK cells and A. fumigatus. We coincubated human NK cells with A. fumigatus hyphae and assessed the gene expression and protein concentration of selected molecules. We found that A. fumigatus up-regulates the gene expression of pro-inflammatory molecules in NK cells, but inhibited the release of these molecules resulting in intracellular accumulation and limited extracellular availability. A. fumigatus down-regulatedmRNA levels of perforin in NK cells, but increased its intra- and extracellular protein concentration. The gene expression of stress related molecules of A. fumigatus such as heat shock protein hsp90 was up-regulated by human NK cells. Our data characterize for the first time the immunosuppressive effect of A. fumigatus on NK cells and may help to develop new therapeutic antifungal strategies.
We have recently shown that caspase-8 is a new substrate of Polo-like kinase 3 (Plk3) that phosphorylates the protein on residue T273 thereby promoting its pro-apoptotic function. In the present study we aimed to investigate the clinical relevance of Plk3 expression and phosphorylation of caspase-8 at T273 in patients with anal squamous cell carcinoma (SSC) treated with 5-fluorouracil and mitomycin C-based chemoradiotherapy (CRT). Immunohistochemical detection of the markers was performed in pretreatment biopsy specimens of 95 patients and was correlated with clinical/histopathologic characteristics including HPV-16 virus load/p16INK4a expression and cumulative incidence of local and distant failure, cancer specific survival (CSS), and overall survival (OS). We observed significant positive correlations between Plk3 expression, pT273 caspase-8 signal, and levels of HPV-16 virus DNA load/p16INK4a detection. Patients with high scores of Plk3 and pT273 caspase-8 showed increased local control (p = 0.011; p = 0.001), increased CSS (p = 0.011; p = 0.013) and OS (p = 0.024; p = 0.001), while the levels of pT273 caspase-8 were significantly associated (p = 0.033) with distant metastases. In multivariate analyses Plk3 expression remained significant for local failure (p = 0.018), CSS (p = 0.016) and OS (p = 0.023). Moreover, a combined HPV16 DNA load and Plk3 or pT273 caspase-8 variable revealed a significant correlation to decreased local failure (p = 0.001; p = 0.009), increased CSS (p = 0.016; p = 0.023) and OS (p = 0.003; p = 0.003). In conclusion these data indicate that elevated levels of Plk3 and pT273 caspase-8 are correlated with favorable clinical outcome in patients with anal SCC treated with concomitant CRT.
Renal cell carcinoma alters endothelial receptor expression responsible for leukocyte adhesion
(2016)
Renal cell carcinoma (RCC) escapes immune recognition. To elaborate the escape strategy the influence of RCC cells on endothelial receptor expression and endothelial leukocyte adhesion was evaluated. Human umbilical vein endothelial cells (HUVEC) were co-cultured with the RCC cell line, Caki-1, with and without tumor necrosis factor (TNF)-alpha. Intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial (E)-selectin, standard and variants (V) of CD44 were then analysed in HUVEC, using flow cytometry and Western blot analysis. To determine which components are responsible for HUVEC-Caki-1 interaction causing receptor alteration, Caki-1 membrane fragments versus cell culture supernatant were applied to HUVECS. Adhesion of peripheral blood lymphocytes (PBL) and polymorphonuclear neutrophils (PMN) to endothelium was evaluated by co-culture adhesion assays. Relevance of endothelial receptor expression for adhesion to endothelium was determined by receptor blockage. Co-culture of RCC and HUVECs resulted in a significant increase in endothelial ICAM-1, VCAM-1, E-selectin, CD44 V3 and V7 expression. Previous stimulation of HUVECs with TNF-alpha and co-cultivation with Caki-1 resulted in further elevation of endothelial CD44 V3 and V7 expression, whereas ICAM-1, VCAM-1 and E-selectin expression were significantly diminished. Since Caki-1 membrane fragments also caused these alterations, but cell culture supernatant did not, cell-cell contact may be responsible for this process. Blocking ICAM-1, VCAM-1, E-selectin or CD44 with respective antibodies led to a significant decrease in PBL and PMN adhesion to endothelium. Thus, exposing HUVEC to Caki-1 results in significant alteration of endothelial receptor expression and subsequent endothelial attachment of PBL and PMN.
Purpose: Few individuals that are latently infected with M. tuberculosis latent tuberculosis infection(LTBI) progress to active disease. We investigated risk factors for LTBI and active pulmonary tuberculosis (PTB) in Germany.
Methods: Healthy household contacts (HHCs), health care workers (HCWs) exposed to M. tuberculosis and PTB patients were recruited at 18 German centres. Interferon-γ release assay (IGRA) testing was performed. LTBI risk factors were evaluated by comparing IGRA-positive with IGRA-negative contacts. Risk factors for tuberculosis were evaluated by comparing PTB patients with HHCs.
Results: From 2008–2014, 603 HHCs, 295 HCWs and 856 PTBs were recruited. LTBI was found in 34.5% of HHCs and in 38.9% of HCWs. In HCWs, care for coughing patients (p = 0.02) and longstanding nursing occupation (p = 0.04) were associated with LTBI. In HHCs, predictors for LTBI were a diseased partner (odds ratio 4.39), sexual contact to a diseased partner and substance dependency (all p < 0.001). PTB was associated with male sex, low body weight (p < 0.0001), alcoholism (15.0 vs 5.9%; p < 0.0001), glucocorticoid therapy (7.2 vs 2.0%; p = 0.004) and diabetes (7.8 vs. 4.0%; p = 0.04). No contact developed active tuberculosis within 2 years follow-up.
Conclusions: Positive IGRA responses are frequent among exposed HHCs and HCWs in Germany and are poor predictors for the development of active tuberculosis.
Measuring NADPH oxidase (Nox)-derived reactive oxygen species (ROS) in living tissues and cells is a constant challenge. All probes available display limitations regarding sensitivity, specificity or demand highly specialized detection techniques. In search for a presumably easy, versatile, sensitive and specific technique, numerous studies have used NADPH-stimulated assays in membrane fractions which have been suggested to reflect Nox activity. However, we previously found an unaltered activity with these assays in triple Nox knockout mouse (Nox1-Nox2-Nox4-/-) tissue and cells compared to wild type. Moreover, the high ROS production of intact cells overexpressing Nox enzymes could not be recapitulated in NADPH-stimulated membrane assays. Thus, the signal obtained in these assays has to derive from a source other than NADPH oxidases. Using a combination of native protein electrophoresis, NADPH-stimulated assays and mass spectrometry, mitochondrial proteins and cytochrome P450 were identified as possible source of the assay signal. Cells lacking functional mitochondrial complexes, however, displayed a normal activity in NADPH-stimulated membrane assays suggesting that mitochondrial oxidoreductases are unlikely sources of the signal. Microsomes overexpressing P450 reductase, cytochromes b5 and P450 generated a NADPH-dependent signal in assays utilizing lucigenin, L-012 and dihydroethidium (DHE). Knockout of the cytochrome P450 reductase by CRISPR/Cas9 technology (POR-/-) in HEK293 cells overexpressing Nox4 or Nox5 did not interfere with ROS production in intact cells. However, POR-/- abolished the signal in NADPH-stimulated assays using membrane fractions from the very same cells. Moreover, membranes of rat smooth muscle cells treated with angiotensin II showed an increased NADPH-dependent signal with lucigenin which was abolished by the knockout of POR but not by knockout of p22phox. In conclusion: the cytochrome P450 system accounts for the majority of the signal of Nox activity chemiluminescence based assays.
Infections of the central nervous system (CNS) are infrequently diagnosed in immunocompetent patients, but they do occur in a significant proportion of patients with hematological disorders. In particular, patients undergoing allogeneic hematopoietic stem-cell transplantation carry a high risk for CNS infections of up to 15%. Fungi and Toxoplasma gondii are the predominant causative agents. The diagnosis of CNS infections is based on neuroimaging, cerebrospinal fluid examination and biopsy of suspicious lesions in selected patients. However, identification of CNS infections in immunocompromised patients could represent a major challenge since metabolic disturbances, side-effects of antineoplastic or immunosuppressive drugs and CNS involvement of the underlying hematological disorder may mimic symptoms of a CNS infection. The prognosis of CNS infections is generally poor in these patients, albeit the introduction of novel substances (e.g. voriconazole) has improved the outcome in distinct patient subgroups. This guideline has been developed by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) with the contribution of a panel of 14 experts certified in internal medicine, hematology/oncology, infectious diseases, intensive care, neurology and neuroradiology. Grades of recommendation and levels of evidence were categorized by using novel criteria, as recently published by the European Society of Clinical Microbiology and Infectious Diseases.