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Objectives: Multidrug-resistant organisms (MDRO) are considered an emerging threat worldwide. Data covering the clinical impact of MDRO colonization in patients with solid malignancies, however, is widely missing. We sought to determine the impact of MDRO colonization in patients who have been diagnosed with Non-small cell lung cancer (NSCLC) who are at known high-risk for invasive infections.
Materials and methods: Patients who were screened for MDRO colonization within a 90-day period after NSCLC diagnosis of all stages were included in this single-center retrospective study.
Results: Two hundred and ninety-five patients were included of whom 24 patients (8.1%) were screened positive for MDRO colonization (MDROpos) at first diagnosis. Enterobacterales were by far the most frequent MDRO detected with a proportion of 79.2% (19/24). MDRO colonization was present across all disease stages and more present in patients with concomitant diabetes mellitus. Median overall survival was significantly inferior in the MDROpos study group with a median OS of 7.8 months (95% CI, 0.0–19.9 months) compared to a median OS of 23.9 months (95% CI, 17.6–30.1 months) in the MDROneg group in univariate (p = 0.036) and multivariate analysis (P = 0.02). Exploratory analyses suggest a higher rate of non-cancer-related-mortality in MDROpos patients compared to MDROneg patients (p = 0.002) with an increased rate of fatal infections in MDROpos patients (p = 0.0002).
Conclusions: MDRO colonization is an independent risk factor for inferior OS in patients diagnosed with NSCLC due to a higher rate of fatal infections. Empirical antibiotic treatment approaches should cover formerly detected MDR commensals in cases of (suspected) invasive infections.
Although immune checkpoint inhibitors such as anti-PD-1 antibodies have shown remarkable clinical success in many different tumor types, the proportion of patients benefiting from this treatment option remains low. Therefore, there is a need to sensitize tumors for immune checkpoint blockade. In this study two approaches were tested, a chemoimmunotherapy approach combining PD-1 checkpoint blockade with doxorubicin (DOX) chemotherapy, and ablation of the sphingosine-1-phosphate (S1P) receptor (S1PR4) based on the following rationale. Chemotherapy was shown to induce immune paralysis which contributes to tumor relapse, while PD-1 signaling was shown to facilitate the acquisition of chemoresistance. Thus, combinatorial chemoimmunotherapy is expected to be beneficial by maintaining or even activating anti-tumor immunity during chemotherapy. S1PR4 is an immune cell specific receptor, whose ablation slowed tumor progression by activating anti-tumor immunity in a mouse model that was previously insensitive to anti-PD-1 monotherapy. This suggested that S1PR4 ablation might pre-activate immunity to sensitize for anti-PD-1 therapy.
To test these combinatorial approaches, two tumor mouse models were employed, namely the MC38 murine adenocarcinoma model as well as the transgenic polyoma middle T oncogene (PyMT) breast cancer model. In the MC38 model, a mild synergistic effect of PD-1 immune checkpoint blockade and S1PR4 ablation was observed, indicated by improved tumor progression and survival as compared to the WT control, and an increased number of tumor-free mice compared to anti-PD-1 therapy alone in WT mice. These observations correlated with an enhanced natural killer (NK) cell infiltrate and increased CXCL9 and CXCL10 production in anti-PD-1 treated S1PR4 KO tumors. As noted before, the PyMT model was largely resistant to anti-PD-1 monotherapy in a therapeutic setting. S1PR4 ablation alone showed significant tumor reduction that was not further enhanced by anti-PD-1 treatment. The same was observed when chemotherapy with DOX was added, where WT tumors relapsed, while S1PR4 KO tumor did not. Addition of anti-PD-1 did only mildly increase tumor control in S1PR4 KO mice, indicating that S1PR4 KO per se very efficiently re-activated anti-tumor immunity. Since S1PR4 KO induces type I 12 interferon (IFN-1) over-production in S1PR4 KO PyMT tumors, a link between high IFN-1 levels and tumor immunity was tested by using mice deficient in the IFN-1 receptor (IFNAR1). Unexpectedly, DOX chemotherapy was most efficient in mice with IFNAR ablation only as compared to WT, S1PR4 KO or S1PR4 and IFNAR1 double KO mice, although deficiency in IFNAR signaling is predominantly regarded as tumor promoting. The underlying mechanisms need to be tested in future studies. Interestingly, chemoimmunotherapy in WT mice prevented tumor relapse to a similar extent than S1PR4 KO and was superior to chemotherapy or immune checkpoint blockade alone. To investigate mechanisms of chemoimmunotherapy success compared to monotherapy, whole transcriptome analysis was used, which identified a set of genes that were upregulated specifically upon chemoimmunotherapy. This gene signature and, more specifically, a condensed four-gene signature predicted favorable survival of human mammary carcinoma patients in the METABRIC cohort.
Moreover, PyMT tumors treated with chemoimmunotherapy contained higher levels of cytotoxic lymphocytes, particularly NK cells. Gene set enrichment analysis and ELISA measurements revealed increased IL-27 production and signaling in PyMT tumors upon chemoimmunotherapy. Moreover, IL-27 improved NK cell cytotoxicity against PyMT cells in vitro. These data supported recent clinical observations indicating a benefit of chemoimmunotherapy compared to monotherapy in breast cancer and suggested potential underlying mechanisms.
Taken together the present work revealed new strategies to reactivate tumor immunity leading to improved chemotherapy response, namely a combination with immune checkpoint blockade and ablation of S1PR4, which activated different lymphocyte compartments within tumors.
The interleukin (IL)-1 family has been described for its numerous involvement in the regulation of inflammatory processes. Certain members are able to induce inflammation, whereas others have the capacity to inhibit inflammation. The newly discovered IL-1 family member IL-38 shows interesting and innovative properties. While most of these cytokines are pro-inflammatory mediators, IL-38 appears to enter the smaller circle of anti-inflammatory mediators. As a pattern, IL-38 appears to suppress IL-17-driven chronic or auto-inflammation by working as receptor antagonist. These properties, as well as its beneficial effects in models of inflammatory and autoimmune diseases suggest the possibility of IL-38-based therapies. Nevertheless, its role in the resolution of acute inflammation, thereby preventing chronic inflammation, remains unclear.
The first part of my thesis elucidated the role of IL-38 in the resolution of inflammation. I found that the complete absence of IL-38 in IL-38 KO mice leads to a delayed resolution of inflammation in the zymosan-induced peritonitis mouse model, compared to WT mice. This was marked by a persistent neutrophilia and a lower production of pro-resolving mediators during the resolution phase, such as TGFβ1 production from macrophages following efferocytosis of apoptotic cells. Reduced TGFβ1 production from macrophages coincided with reduced levels of regulatory T cells (Tregs), which are known to promote the resolution of inflammation. Unexpectedly, the TGFβ1 production capacity of macrophages did not influence the induction of Tregs from naïve T cells. Rather, IL-38 KO mice had an accumulation of Tregs in the thymus compared to WT mice. This was caused by an impairment of CD62L expression at the surface of Tregs, which is required for Tregs migration outside of the thymus. Higher Treg numbers in the thymus correlated with lower level of Tregs in peripheral lymphoid organs. Importantly, CD62L expression at the surface of IL-38 KO Tregs in the thymus was restored by injecting IL-38 i.p. for 24h. These data indicate a potential key function of IL-38 in the regulation of Treg migration, which is triggered in many cases of autoimmunity.
The second part of my thesis was to study the role of IL-38 in experimental autoimmune encephalomyelitis (EAE) development, given that EAE is IL-17-dependent. Unexpectedly, IL-38-deficient mice showed strongly reduced clinical scores and histological markers of EAE. This came with reduced inflammatory cell infiltrates, as well as reduced expression of inflammatory markers in the spinal cord. IL-38 mRNA was detected in the spinal cord, mainly by resident and infiltrated phagocytes, but also by other cells, such as ependymal cells. IL-38 was upregulated upon pro-inflammatory stimulation of bone marrow-derived macrophages, and its presence was necessary for a complete activation of inflammatory macrophages. My data suggest an alternative cell-intrinsic role of IL-38 in macrophages to promote inflammation in the central nervous system.
In the last part of my thesis, I initiated a project on the function of IL-38 in B cell physiology and antibody production, given the fact that IL-38 is expressed by B cells. I generated preliminary data showing that the absence of IL-38 in mice decreased antibody production. Furthermore, I showed that IL-38 is particularly expressed by plasma cells in human tonsils. This project remains open and further studies will be conducted to investigate how IL-38 regulates antibody production, both in physiological and autoimmune settings. Understanding the role of IL-38 in autoantibody production could lead to original and innovative therapy for patients suffering from auto-inflammatory disease.
In summary, the different projects of my thesis provide evidence that the pro-resolving function of IL-38 may be indirectly linked to the retention of Tregs in the thymus. Moreover, a possible intracellular role of IL-38 within macrophages was described showing opposite properties in the regulation of inflammation. This function could be causatively involved in EAE development. However, further studies remain to be done to find the mechanism of action by which IL-38 regulates Tregs egression and how it influences the EAE development. Complete understanding of the IL-38 biology and differentiation between its extra- vs potential intracellular functions could make it a promising therapeutic target for chronic inflammatory or autoimmune diseases.
Reliable and efficient recording of the error-related negativity with a speeded Eriksen Flanker task
(2020)
There is accumulating evidence that the error-related negativity (ERN), an event-related potential elicited after erroneous actions, is altered in different psychiatric disorders and may help to guide treatment options. Thus, the ERN is a promising candidate as a psychiatric biomarker. Basic methodological requirements for a biomarker are standardized and reliable measurements. Additional psychiatry specific requirements are time efficiency and patient-friendliness.
The aim of the present study is to establish ERN acquisition in a reliable, time-efficient and patient-friendly way for use in clinical practice.
Healthy subjects (N=27) performed a modified Eriksen Flanker Task with adaptive reaction time window and only incongruent stimuli that maximizes the number of errors. All participants were tested for mental health by the Mini International Neuropsychiatric Interview (M.I.N.I.). The first N=12 subjects were part of a pilot study and further N=14 subjects were included for analysis (one subject was excluded due to technical problems). In a test-retest design with two sessions separated by 28 days the reliability of the ERN has been assessed. To ensure external validity, we aimed to replicate previously reported correlation patterns of ERN amplitude with (1) number of errors and (2) negative affect. State affect of each subject was measured by the Positive and Negative Affect Schedule. In order to optimize the clinical use of the task, we determined to which extent the task can be shortened while keeping reliability >0.80.
We found excellent reliability of the ERN (intraclass correlation coefficient =0.806-0.947) and replicated specific correlation patterns (ERN amplitude with relative number of errors: r=0.394; p=0.082; ERN amplitude with negative affect: r=-0.583, p=0.014). The task can be shortened to a patient-friendly and clinically feasible length of only 8 minutes keeping reliability >0.80.
To conclude, the present modified task provides reliable and efficient recording of the ERN, facilitating its use as a psychiatric biomarker.
Bipolar disorder (BD) and major depressive disorder (MDD) are severe mood disorders that belong to the most debilitating diseases worldwide. Differentiating both mood disorders often poses a major clinical challenge, leading to frequent misdiagnoses. Objective biomarkers able to differentiate individuals with BD and MDD therefore represent a psychiatric research field of utmost importance. Recent studies have applied resting-state fMRI paradigms and found promising results differentiating both disorders based on the acquired data. However, most of these studies have focused their efforts on acutely depressed patients. Thus, it remains unclear whether the aberrations remain in a symptomless disease state.
The here presented study addresses these issues by evaluating the ability to differentiate both disorders from one another by conducting a between-group comparison of functional brain network connectivity (FNC) obtained from resting-state fMRI data. Data were collected from 20 BD, 15 MDD patients and 30 age- and gender-matched healthy controls (HC). Graph theoretical analyses were applied to detect differences in functional network organization between the groups on a global and regional network level.
Network analysis detected frontal, temporal and subcortical nodes in emotion regulation areas such as the limbic system and associated regions exhibiting significant differences in network integration and segregation in BD compared to MDD patients and HC. Participants with MDD and HC only differed in frontal and insular network centrality.
These results indicate that a significantly altered brain network topology in the limbic system might be a trait marker specific to BD. Brain network analysis in these regions may therefore be used to differentiate euthymic BD not only from HC but also from patients with MDD.
Colorectal cancer (CRC) is one of the most frequently diagnosed tumor in humans and one of the most common causes of cancer-related death worldwide. The pathogenesis of CRC follows a multistage process which together with somatic gene mutations is mainly attributed to the dysregulation of signaling pathways critically involved in the maintenance of homeostasis of epithelial integrity in the intestine. A growing number of studies has highlighted the critical impact of members of the tripartite motif (TRIM) protein family on most types of human malignancies including CRC. In accordance, abundant expression of many TRIM proteins has been observed in CRC tissues and is frequently correlating with poor survival of patients. Notably, some TRIM members can act as tumor suppressors depending on the context and the type of cancer which has been assessed. Mechanistically, most cancer-related TRIMs have a critical impact on cell cycle control, apoptosis, epithelial–mesenchymal transition (EMT), metastasis, and inflammation mainly through directly interfering with diverse oncogenic signaling pathways. In addition, some recent publications have emphasized the emerging role of some TRIM members to act as transcription factors and RNA-stabilizing factors thus adding a further level of complexity to the pleiotropic biological activities of TRIM proteins. The current review focuses on oncogenic signaling processes targeted by different TRIMs and their particular role in the development of CRC. A better understanding of the crosstalk of TRIMs with these signaling pathways relevant for CRC development is an important prerequisite for the validation of TRIM proteins as novel biomarkers and as potential targets of future therapies for CRC.
Obstructive Sleep Apnea is emerging as a global health epidemic, particularly due to the obesity pandemic. However, comprehensive prevalence data are still lacking and global OSA research has not yet been structurally evaluated. Using the latest comprehensive age/gender-specific BMI and obesity data, a global landscape estimating the risk/burden of OSA was created. Results were presented in relation to an in-depth analysis of OSA research and countries’ socioeconomic/scientific background. While the USA, Canada, and Japan are the highest publishing countries on OSA, Iceland, Greece, and Israel appeared at the forefront when relating the scientific output to socioeconomic parameters. Conversely, China, India, and Russia showed relatively low performances in these relations. Analysis of the estimated population at risk (EPR) of OSA showed the USA, China, India, and Brazil as the leading countries. Although the EPR and OSA research correlated strongly, major regional discrepancies between the estimated demand and actual research performances were identified, mainly in, but not limited to, developing nations. Our study highlights regional challenges/imbalances in the global activity on OSA and allows targeted measures to mitigate the burden of undiagnosed/untreated OSA. Furthermore, the inclusion of disadvantaged countries in international collaborations could stimulate local research efforts and provide valuable insights into the regional epidemiology of OSA.
Reduced external knee adduction moments in the second half of stance after total hip replacement have been reported in hip osteoarthritis patients. This reduction is thought to shift the load from the medial to the lateral knee compartment and as such increase the risk for knee osteoarthritis. The knee adduction moment is a surrogate for the load distribution between the medial and lateral compartments of the knee and not a valid measure for the tibiofemoral contact forces which are the result of externally applied forces and muscle forces. The purpose of this study was to investigate whether the distribution of the tibiofemoral contact forces over the knee compartments in unilateral hip osteoarthritis patients 1 year after receiving a primary total hip replacement differs from healthy controls. Musculoskeletal modeling on gait was performed in OpenSim using the detailed knee model of Lerner et al. (2015) for 19 patients as well as for 15 healthy controls of similar age. Knee adduction moments were calculated by the inverse dynamics analysis, medial and lateral tibiofemoral contact forces with the joint reaction force analysis. Moments and contact forces of patients and controls were compared using Statistical Parametric Mapping two-sample t-tests. Knee adduction moments and medial tibiofemoral contact forces of both the ipsi- and contralateral leg were not significantly different compared to healthy controls. The contralateral leg showed 14% higher medial tibiofemoral contact forces compared to the ipsilateral (operated) leg during the second half of stance. During the first half of stance, the lateral tibiofemoral contact force of the contralateral leg was 39% lower and the ratio 32% lower compared to healthy controls. In contrast, during the second half of stance the forces were significantly higher (39 and 26%, respectively) compared to healthy controls. The higher ratio indicates a changed distribution whereas the increased lateral tibiofemoral contact forces indicate a higher lateral knee joint loading in the contralateral leg in OA patients after total hip replacement (THR). Musculoskeletal modeling using a detailed knee model can be useful to detect differences in the load distribution between the medial and lateral knee compartment which cannot be verified with the knee adduction moment.
Objective: Many patients with localized prostate cancer (PCa) do not immediately undergo radical prostatectomy (RP) after biopsy confirmation. The aim of this study was to investigate the influence of “time-from-biopsy-to- prostatectomy” on adverse pathological outcomes.
Materials and Methods: Between January 2014 and December 2019, 437 patients with intermediate- and high risk PCa who underwent RP were retrospectively identified within our prospective institutional database. For the aim of our study, we focused on patients with intermediate- (n = 285) and high-risk (n = 151) PCa using D'Amico risk stratification. Endpoints were adverse pathological outcomes and proportion of nerve-sparing procedures after RP stratified by “time-from-biopsy-to-prostatectomy”: ≤3 months vs. >3 and < 6 months. Medians and interquartile ranges (IQR) were reported for continuously coded variables. The chi-square test examined the statistical significance of the differences in proportions while the Kruskal-Wallis test was used to examine differences in medians. Multivariable (ordered) logistic regressions, analyzing the impact of time between diagnosis and prostatectomy, were separately run for all relevant outcome variables (ISUP specimen, margin status, pathological stage, pathological nodal status, LVI, perineural invasion, nerve-sparing).
Results: We observed no difference between patients undergoing RP ≤3 months vs. >3 and <6 months after diagnosis for the following oncological endpoints: pT-stage, ISUP grading, probability of a positive surgical margin, probability of lymph node invasion (LNI), lymphovascular invasion (LVI), and perineural invasion (pn) in patients with intermediate- and high-risk PCa. Likewise, the rates of nerve sparing procedures were 84.3 vs. 87.4% (p = 0.778) and 61.0% vs. 78.8% (p = 0.211), for intermediate- and high-risk PCa patients undergoing surgery after ≤3 months vs. >3 and <6 months, respectively. In multivariable adjusted analyses, a time to surgery >3 months did not significantly worsen any of the outcome variables in patients with intermediate- or high-risk PCa (all p > 0.05).
Conclusion: A “time-from-biopsy-to-prostatectomy” of >3 and <6 months is neither associated with adverse pathological outcomes nor poorer chances of nerve sparing RP in intermediate- and high-risk PCa patients.
MicroRNAs (miRNAs) have emerged as critical posttranscriptional regulators of the immune system, including function and development of regulatory T (Treg) cells. Although this critical role has been firmly demonstrated through genetic models, key mechanisms of miRNA function in vivo remain elusive. Here, we review the role of miRNAs in Treg cell development and function. In particular, we focus on the question what the study of miRNAs in this context reveals about miRNA biology in general, including context-dependent function and the role of individual targets vs. complex co-targeting networks. In addition, we highlight potential technical pitfalls and state-of-the-art approaches to improve the mechanistic understanding of miRNA biology in a physiological context.