Karolinska Institutet
  • Solna, Stockholm, Sweden
Recent publications
In this article, we examine the adaptation of learning among scientists and healthcare professionals in conferences and symposia from face-to-face to fully virtual meetings accelerated in the last years. Advantages and limitations for both settings have been described in different research studies but the effectiveness of learning can be reflected similarly by applying five fundamental principles of learning, which are based on empirical research in cognitive psychology. From a practical context, we compared the individual learning outcomes from two satellite symposia conducted face-to-face in 2019 and virtually in 2021 at the European Congress of Urology, EAU. Although both conference formats were almost identical, the five principles of learning were applied in both symposia. There were also some differences due to adaptation to online conferences, and our findings suggest that the virtual conference was perceived as significantly more effective than the face-to-face conference on all five criteria, and digital learning is a valid alternative to face-to-face conferences. What still needs to be better understood and analysed is the informal learning that is taking place during conferences, but suggesting an active design of any digital event by combining “technical literacy· with “learning literacy” will enable us to better analyse and study the impact of learning using the five learning principles in the design of other events in the future.
Objective: To evaluate the efficacy, feasibility and acceptability of microwave ablation (MWA) compared to uterine artery embolization (UAE) as treatment for uterine fibroids. Method: A randomized controlled superiority trial, including premenopausal women 30-55 years, with symptomatic uterine fibroids without any single fibroid exceeding mean diameter of eight centimeters. Patients were randomized to receive microwave ablation, performed abdominally or vaginally, or to uterine artery embolization. The primary outcome was volume difference of the three largest fibroids at 6 months post treatment evaluated by magnetic resonance imaging (MRI) by a blinded radiologist analyzed by Mann-Whitney U-test. Secondary outcomes included symptom severity score (SSS), health related quality of life (HR-QoL), amount of menstrual bleeding, postoperative pain, length of hospitalization, need for additional treatment, adverse events and if patients would recommend the treatment to a friend. Results: Patients were recruited from 30 January 2017 to 12 September 2019, with a total of 17 patients treated in each group from May 2017 to December 2019. Superiority of MWA could not be established. The volume reduction was 41.8% (Interquartile range, IQR, 14-63) in the MWA group compared to 62.2% (IQR 34.9-80.1) in the UAE group (p = 0.29). Effects on symptoms, HR-QoL and acceptability did not differ between groups. Days of hospitalization and sick leave were significantly fewer in the MWA group (p < 0.001 and p = 0.001). Conclusions: Although superiority of MWA could not be established, it is a promising technique for treating uterine fibroids. It was well tolerated and associated with lower use of health care resources. Trial registration: NCT02942537, www.clincialtrials.gov.
Cancer is associated with systemic pathologies that contribute to mortality, such as thrombosis and distant organ failure. The aim of this study was to investigate the potential role of neutrophil extracellular traps (NETs) in myocardial inflammation and tissue damage in treatment-naïve individuals with cancer. Mice with mammary carcinoma (MMTV-PyMT) had increased plasma levels of NETs measured as H3Cit-DNA complexes, paralleled with elevated coagulation, compared to healthy littermates. MMTV-PyMT mice displayed upregulation of pro-inflammatory markers in the heart, myocardial hypertrophy and elevated cardiac disease biomarkers in the blood, but not echocardiographic heart failure. Moreover, increased endothelial proliferation was observed in hearts from tumor-bearing mice. Removal of NETs by DNase I treatment suppressed the myocardial inflammation, expression of cardiac disease biomarkers and endothelial proliferation. Compared to a healthy control group, treatment-naïve cancer patients with different malignant disorders had increased NET formation, which correlated to plasma levels of the inflammatory marker CRP and the cardiac disease biomarkers NT-proBNP and sTNFR1, in agreement with the mouse data. Altogether, our data indicate that NETs contribute to inflammation and myocardial stress during malignancy. These findings suggest NETs as potential therapeutic targets to prevent cardiac inflammation and dysfunction in cancer patients.
Background: In thermal ablation of malignant liver tumors, ablation dimensions remain poorly predictable. This study aimed to investigate factors influencing volumetric ablation dimensions in patients treated with stereotactic microwave ablation (SMWA) for colorectal liver metastases (CRLM). Methods: Ablation volumes from CRLM ≤3 cm treated with SMWA within a prospective European multicentre trial were segmented. Correlations between applied ablation energies and resulting effective ablation volumes (EAV) and ablation volume irregularities (AVI) were investigated. A novel measure for AVI, including minimum enclosing and maximum inscribed ellipsoid ablation volumes, and a surrogate parameter for the expansion of ablation energy (EAV per applied energy), was introduced. Potential influences of tumor and patient-specific factors on EAV per applied energy and AVI were analyzed using multivariable mixed-effects models. Results: A total of 116 ablations from 71 patients were included for analyses. Correlations of EAV or AVI and ablation energy were weak to moderate, with a maximum of 25% of the variability in EAV and 13% in AVI explained by the applied ablation energy. On multivariable analysis, ablation expansion (EAV per applied ablation energy) was influenced mainly by the tumor radius (B = -0.03, [CI -0.04, -0.007]). AVI was significantly larger with higher applied ablation energies (B = 0.002 [CI 0.0007, 0.002]]); liver steatosis, KRAS mutation, subcapsular location or proximity to major blood vessels had no influence. Conclusions: This study confirmed that factors beyond the applied ablation energy might affect volumetric ablation dimensions, resulting in poor predictability. Further clinical trials including tissue sampling are needed to relate physical tissue properties to ablation expansion.
Protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and associated clinical sequelae requires well-coordinated metabolic and immune responses that limit viral spread and promote recovery of damaged systems. However, the role of the gut microbiota in regulating these responses has not been thoroughly investigated. In order to identify mechanisms underpinning microbiota interactions with host immune and metabolic systems that influence coronavirus disease 2019 (COVID-19) outcomes, we performed a multi-omics analysis on hospitalized COVID-19 patients and compared those with the most severe outcome (i.e. death, n = 41) to those with severe non-fatal disease (n = 89), or mild/moderate disease (n = 42), that recovered. A distinct subset of 8 cytokines (e.g. TSLP) and 140 metabolites (e.g. quinolinate) in sera identified those with a fatal outcome to infection. In addition, elevated levels of multiple pathobionts and lower levels of protective or anti-inflammatory microbes were observed in the fecal microbiome of those with the poorest clinical outcomes. Weighted gene correlation network analysis (WGCNA) identified modules that associated severity-associated cytokines with tryptophan metabolism, coagulation-linked fibrinopeptides, and bile acids with multiple pathobionts, such as Enterococcus. In contrast, less severe clinical outcomes are associated with clusters of anti-inflammatory microbes such as Bifidobacterium or Ruminococcus, short chain fatty acids (SCFAs) and IL-17A. Our study uncovered distinct mechanistic modules that link host and microbiome processes with fatal outcomes to SARS-CoV-2 infection. These features may be useful to identify at risk individuals, but also highlight a role for the microbiome in modifying hyperinflammatory responses to SARS-CoV-2 and other infectious agents.
Objective. Patients with underlying heart diseases have a higher risk of dying from Covid-19. It has also been suggested that Covid-19 affects the heart through myocarditis. Despite the rapidly growing research on the management of Covid-19 associated complications, most of the ongoing research is focused on the respiratory complications of Covid-19, and little is known about the prevalence of myocarditis. Design. This study aimed to characterize myocardial involvement by using a panel of antibodies to detect hypoxic and inflammatory changes and the presence of SARS-CoV-2 proteins in heart tissues obtained during the autopsy procedure of Covid-19 deceased patients. Thirty-seven fatal COVID-19 cases and 21 controls were included in this study. Results. Overall, the Covid-19 hearts had several histopathological changes like the waviness of myocytes, fibrosis, contract band necrosis, infiltration of polymorphonuclear neutrophils, vacuolization, and necrosis of myocytes. In addition, endothelial damage and activation were detected in heart tissue. However, viral replication was not detected using RNA in situ hybridization. Also, lymphocyte infiltration, as a hallmark of myocarditis, was not seen in this study. Conclusion. No histological sign of myocarditis was detected in any of our cases; our findings are thus most congruent with the hypothesis of the presence of a circulating endothelium activating factor such as VEGF, originating outside of the heart, probably from the hypoxic part of the Covid-19 lungs.
Successful translation of chimeric antigen receptor (CAR) T cell therapy for the treatment of solid tumors has proved to be troublesome, mainly due to the complex tumor microenvironment promoting T cell dysfunction and antigen heterogeneity. Mesothelin (MSLN) has emerged as an attractive target for CAR T cell therapy of several solid malignancies, including ovarian cancer. To improve clinical response rates with MSLN-CAR T cells, a better understanding of the mechanisms impacting CAR T cell functionality in vitro is crucial. Here, we demonstrated superior cytolytic capacity of CD28-costimulated MSLN-CAR T cells (M28z) relative to 4-1BB-costimulated MSLN-CAR T cells (MBBz). Furthermore, CD28-costimulated MSLN CAR T cells displayed enhanced cytolytic capacity against tumor spheroids with heterogeneous MSLN expression compared to MBBz CAR T cells. In this study, we identified CAR-mediated trogocytosis as a potential impeding factor for successful MSLN-CAR T cell therapy due to fratricide killing and contributing to tumor antigen heterogeneity. Moreover, we link antigen-dependent upregulation of LAG-3 with reduced CAR T cell functionality. Taken together, our study highlights the therapeutic potential and bottlenecks of MSLN-CAR T cells, providing a rationale for combinatorial treatment strategies.
Objectives. The aim of this study was to analyse the risk of valvular heart diseases among foreign-born individuals in Sweden. Design. This was a nationwide study of individuals aged 18 years of age and older (N = 6,118,649; 2,970,055 men and 3,148,594 women). Valvular heart diseases were defined as at least one registered diagnosis in the National Patient Register between 1 January 1998 and 31 December 2012. Cox regression analysis was used to estimate hazard ratios (HR) with 99% confidence intervals (CI) of incident valvular heart diseases in foreign-born individuals compared to Swedish natives. The Cox regression models were adjusted for age, co-morbidities, and sociodemographic factors. Sub-categories were chronic rheumatic valvular heart diseases and non-rheumatic valvular heart diseases. Results. There were 64,979 male cases and 59,075 female cases. Fully adjusted HRs (99% CI) were among immigrant men 0.86 (0.82-0.89) and immigrant women 0.96 (0.92-1.00). For chronic rheumatic valvular disease among immigrant men and women, the HRs were 1.62 (1.37-1.92) and 1.75 (1.52-2.00), respectively, and, for non-rheumatic valvular disease among immigrant men 0.83 (0.80-0.87) and immigrant women 0.92 (0.88-0.96). Increased risks for chronic rheumatic valvular disease were found among men from Southern, Eastern and Central Europe, Africa and Asia and among women from Western, Eastern and Central Europe and Africa, Latin America and Asia. Conclusions. We observed lower risks in general of valvular heart disease, but higher risks of chronic rheumatic valvular heart disease in immigrants, which is important in the clinical situation.
Tyrosine kinase inhibitors (TKIs) have dramatically improved the survival in chronic myeloid leukemia (CML), but residual disease typically persists even after prolonged treatment. Several lines of evidence suggest that TKIs administered to CML patients upregulate interferon γ (IFNγ) production, which may counteract the anti-tumorigenic effects of the therapy. We now show that activated T cell-conditioned medium (TCM) enhanced proliferation and counteracted imatinib-induced apoptosis of CML cells, and addition of a neutralizing anti-IFNγ antibody at least partially inhibited the anti-apoptotic effect. Likewise, recombinant IFNγ also reduced imatinib-induced apoptosis of CML cells. This anti-apoptotic effect of IFNγ was independent of alternative IFNγ signaling pathways, but could be notably diminished by STAT1-knockdown. Furthermore, IFNγ upregulated the expression of several anti-apoptotic proteins, including MCL1, PARP9, and PARP14, both in untreated and imatinib-treated primary human CD34+ CML stem/progenitor cells. Our results suggest that activated T cells in imatinib-treated CML patients can directly rescue CML cells from imatinib-induced apoptosis at least partially through the secretion of IFNγ, which exerts a rapid, STAT1-dependent anti-apoptotic effect potentially through the simultaneous upregulation of several key hematopoietic survival factors. These mechanisms may have a major clinical impact, when targeting residual leukemic stem/progenitor cells in CML.
Background Genome-wide association studies (GWAS) have identified multiple common breast cancer susceptibility variants. Many of these variants have differential associations by estrogen receptor (ER) status, but how these variants relate with other tumor features and intrinsic molecular subtypes is unclear. Methods Among 106,571 invasive breast cancer cases and 95,762 controls of European ancestry with data on 173 breast cancer variants identified in previous GWAS, we used novel two-stage polytomous logistic regression models to evaluate variants in relation to multiple tumor features (ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and grade) adjusting for each other, and to intrinsic-like subtypes. Results Eighty-five of 173 variants were associated with at least one tumor feature (false discovery rate < 5%), most commonly ER and grade, followed by PR and HER2. Models for intrinsic-like subtypes found nearly all of these variants (83 of 85) associated at p < 0.05 with risk for at least one luminal-like subtype, and approximately half (41 of 85) of the variants were associated with risk of at least one non-luminal subtype, including 32 variants associated with triple-negative (TN) disease. Ten variants were associated with risk of all subtypes in different magnitude. Five variants were associated with risk of luminal A-like and TN subtypes in opposite directions. Conclusion This report demonstrates a high level of complexity in the etiology heterogeneity of breast cancer susceptibility variants and can inform investigations of subtype-specific risk prediction.
Androgen receptor (AR) is an important prognostic marker and therapeutic target in luminal androgen receptor triple-negative breast cancer (LAR TNBC) and prostate cancer (PCa). Endoplasmic reticulum (ER) stress may activate the unfolded protein response (UPR) to regulate associated protein expression and is closely related to tumor growth and drug resistance. The effect of ER stress on AR expression and signaling remains unclear. Here, we focused on the regulation and underlying mechanism of AR expression induced by ER stress in LAR TNBC and PCa. Western blotting and quantitative RT-PCR results showed that AR expression was markedly decreased under ER stress induced by thapsigargin and brefeldin A, and this effect was dependent on PERK/eIF2α/ATF4 signaling activation. Chromatin immunoprecipitation-PCR and luciferase reporter gene analysis results showed that ATF4 bound to the AR promoter regions to inhibit its activity. Moreover, ATF4 overexpression inhibited tumor proliferation and AR expression both in vitro and in vivo. Collectively, these results demonstrated that ER stress could decrease AR mRNA and protein levels via PERK/eIF2α/ATF4 signaling in LAR TNBC and PCa. Targeting the UPR may be a treatment strategy for AR-dependent TNBC and PCa.
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9,412 members
Christopher R. Cederroth
  • Department of Physiology and Pharmacology
André Görgens
  • Department of Laboratory Medicine
Johanna Viiliäinen
  • Department of Cell and Molecular Biology
Pekka Kohonen
  • Institute of Environmental Medicine - IMM
Nobels väg 6, 17177, Solna, Stockholm, Sweden
Head of institution
Ole Petter Ottersen
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