Background: Selective outcome reporting in clinical trials introduces bias in the body of evidence distorting clinical decision making. Trial registration aims to prevent this bias and is suggested by the International Committee of Medical Journal Editors (ICMJE) since 2004. Methods: The 585 randomized controlled trials (RCTs) published between 1965 and 2017 that were included in a recently published Cochrane review on antiemetic drugs for prevention of postoperative nausea and vomiting were selected. In a retrospective study, we assessed trial registration and selective outcome reporting by comparing study publications with their registered protocols according to the ‘Cochrane Risk of bias’ assessment tool 1.0. Results: In the Cochrane review, the first study which referred to a registered trial protocol was published in 2004. Of all 585 trials included in the Cochrane review, 334 RCTs were published in 2004 or later, of which only 22% (75/334) were registered. Among the registered trials, 36% (27/75) were pro- and 64% (48/75) were retrospectively registered. 41% (11/27) of the prospectively registered trials were free of selective outcome reporting bias, 22% (6/27) were incompletely registered and assessed as unclear risk, and 37% (10/27) were assessed as high risk. Major outcome discrepancies between registered and published high risk trials were a change from the registered primary to a published secondary outcome (32%), a new primary outcome (26%), and different outcome assessment times (26%). Among trials with high risk of selective outcome reporting 80% favoured at least one statistically significant result. Registered trials were assessed more often as ‘overall low risk of bias’ compared to non-registered trials (64% vs 28%). Conclusions: In 2017, 13 years after the ICMJE declared prospective protocol registration a necessity for reliable clinical studies, the frequency and quality of trial registration in the field of PONV is very poor. Selective outcome reporting reduces trustworthiness in findings of clinical trials. Investigators and clinicians should be aware that only following a properly registered protocol and transparently reporting of predefined outcomes, regardless of the direction and significance of the result, will ultimately strengthen the body of evidence in the field of PONV research in the future.

Background: In principle, the elimination of malignancies by oncolytic virotherapy could proceed by different mechanisms - e.g. tumor cell specific oncolysis, destruction of the tumor vasculature or an anti-tumoral immunological response. In this study, we analyzed the contribution of these factors to elucidate the responsible mechanism for regression of human breast tumor xenografts upon colonization with an attenuated vaccinia virus (VACV). Methods: Breast tumor xenografts were analyzed 6 weeks post VACV infection (p.i.; regression phase) by immunohistochemistry and mouse-specific expression arrays. Viral-mediated oncolysis was determined by tumor growth analysis combined with microscopic studies of intratumoral virus distribution. The tumor vasculature was morphologically characterized by diameter and density measurements and vessel functionality was analyzed by lectin perfusion and extravasation studies. Immunological aspects of viral-mediated tumor regression were studied in either immune-deficient mouse strains (T-, B-, NK-cell-deficient) or upon cyclophosphamide-induced immunosuppression (MHCII+-cell depletion) in nude mice. Results: Late stage VACV-infected breast tumors showed extensive necrosis, which was highly specific to cancer cells. The tumor vasculature in infected tumor areas remained functional and the endothelial cells were not infected. However, viral colonization triggers hyperpermeability and dilatation of the tumor vessels, which resembled the activated endothelium in wounded tissue. Moreover, we demonstrated an increased expression of genes involved in leukocyte-endothelial cell interaction in VACV-infected tumors, which orchestrate perivascular inflammatory cell infiltration. The immunohistochemical analysis of infected tumors displayed intense infiltration of MHCII-positive cells and colocalization of tumor vessels with MHCII+/CD31+ vascular leukocytes. However, GI-101A tumor growth analysis upon VACV-infection in either immunosuppressed nude mice (MHCII+-cell depleted) or in immune-deficient mouse strains (T-, B-, NK-cell-deficient) revealed that neither MHCII-positive immune cells nor T-, B-, or NK cells contributed significantly to VACV-mediated tumor regression. In contrast, tumors of immunosuppressed mice showed enhanced viral spreading and tumor necrosis. Conclusions: Taken together, these results indicate that VACV-mediated oncolysis is the primary mechanism of tumor shrinkage in the late regression phase. Neither the destruction of the tumor vasculature nor the massive VACV-mediated intratumoral inflammation was a prerequisite for tumor regression. We propose that approaches to enhance viral replication and spread within the tumor microenvironment should improve therapeutical outcome.

Background: COVID-19 patients are at high thrombotic risk. The safety and efficacy of different anticoagulation regimens in COVID-19 patients remain unclear. Methods: We searched for randomised controlled trials (RCTs) comparing intermediate- or therapeutic-dose anticoagulation to standard thromboprophylaxis in hospitalised patients with COVID-19 irrespective of disease severity. To assess efficacy and safety, we meta-analysed data for all-cause mortality, clinical status, thrombotic event or death, and major bleedings. Results: Eight RCTs, including 5580 patients, were identified, with two comparing intermediate- and six therapeutic-dose anticoagulation to standard thromboprophylaxis. Intermediate-dose anticoagulation may have little or no effect on any thrombotic event or death (RR 1.03, 95% CI 0.86–1.24), but may increase major bleedings (RR 1.48, 95% CI 0.53–4.15) in moderate to severe COVID-19 patients. Therapeutic-dose anticoagulation may decrease any thrombotic event or death in patients with moderate COVID-19 (RR 0.64, 95% CI 0.38–1.07), but may have little or no effect in patients with severe disease (RR 0.98, 95% CI 0.86–1.12). The risk of major bleedings may increase independent of disease severity (RR 1.78, 95% CI 1.15–2.74). Conclusions: Certainty of evidence is still low. Moderately affected COVID-19 patients may benefit from therapeutic-dose anticoagulation, but the risk for bleeding is increased.

Background: Oncolytic viruses, including vaccinia virus (VACV), are a promising alternative to classical mono-cancer treatment methods such as surgery, chemo- or radiotherapy. However, combined therapeutic modalities may be more effective than mono-therapies. In this study, we enhanced the effectiveness of oncolytic virotherapy by matrix metalloproteinase (MMP-9)-mediated degradation of proteins of the tumoral extracellular matrix (ECM), leading to increased viral distribution within the tumors. Methods: For this study, the oncolytic vaccinia virus GLV-1h255, containing the mmp-9 gene, was constructed and used to treat PC-3 tumor-bearing mice, achieving an intra-tumoral over-expression of MMP-9. The intra-tumoral MMP-9 content was quantified by immunohistochemistry in tumor sections. Therapeutic efficacy of GLV-1h255 was evaluated by monitoring tumor growth kinetics and intra-tumoral virus titers. Microenvironmental changes mediated by the intra-tumoral MMP-9 over-expression were investigated by microscopic quantification of the collagen IV content, the blood vessel density (BVD) and the analysis of lymph node metastasis formation. Results: GLV-1h255-treatment of PC-3 tumors led to a significant over-expression of intra-tumoral MMP-9, accompanied by a marked decrease in collagen IV content in infected tumor areas, when compared to GLV-1h68-infected tumor areas. This led to considerably elevated virus titers in GLV-1h255 infected tumors, and to enhanced tumor regression. The analysis of the BVD, as well as the lumbar and renal lymph node volumes, revealed lower BVD and significantly smaller lymph nodes in both GLV-1h68- and GLV-1h255- injected mice compared to those injected with PBS, indicating that MMP-9 over-expression does not alter the metastasis-reducing effect of oncolytic VACV. Conclusions: Taken together, these results indicate that a GLV-1h255-mediated intra-tumoral over-expression of MMP-9 leads to a degradation of collagen IV, facilitating intra-tumoral viral dissemination, and resulting in accelerated tumor regression. We propose that approaches which enhance the oncolytic effect by increasing the intra-tumoral viral load, may be an effective way to improve therapeutic outcome.

Background Oncolytic virotherapy is a novel approach for the treatment of glioblastoma multiforme (GBM) which is still a fatal disease. Pathologic features of GBM are characterized by the infiltration with microglia/macrophages and a strong interaction between immune- and glioma cells. The aim of this study was to determine the role of microglia and astrocytes for oncolytic vaccinia virus (VACV) therapy of GBM. Methods VACV LIVP 1.1.1 replication in C57BL/6 and \(Foxn1^{nu/nu}\) mice with and without GL261 gliomas was analyzed. Furthermore, immunohistochemical analysis of microglia and astrocytes was investigated in non-, mock-, and LIVP 1.1.1-infected orthotopic GL261 gliomas in C57BL/6 mice. In cell culture studies virus replication and virus-mediated cell death of GL261 glioma cells was examined, as well as in BV-2 microglia and IMA2.1 astrocytes with M1 or M2 phenotypes. Co-culture experiments between BV-2 and GL261 cells and apoptosis/necrosis studies were performed. Organotypic slice cultures with implanted GL261 tumor spheres were used as additional cell culture system. Results We discovered that orthotopic GL261 gliomas upon intracranial virus delivery did not support replication of LIVP 1.1.1, similar to VACV-infected brains without gliomas. In addition, recruitment of \(Iba1^+\) microglia and \(GFAP^+\) astrocytes to orthotopically implanted GL261 glioma sites occurred already without virus injection. GL261 cells in culture showed high virus replication, while replication in BV-2 and IMA2.1 cells was barely detectable. The reduced viral replication in BV-2 cells might be due to rapid VACV-induced apoptotic cell death. In BV-2 and IMA 2.1 cells with M1 phenotype a further reduction of virus progeny and virus-mediated cell death was detected. Application of BV-2 microglial cells with M1 phenotype onto organotypic slice cultures with implanted GL261 gliomas resulted in reduced infection of BV-2 cells, whereas GL261 cells were well infected. Conclusion Our results indicate that microglia and astrocytes, dependent on their activation state, may preferentially clear viral particles by immediate uptake after delivery. By acting as VACV traps they further reduce efficient virus infection of the tumor cells. These findings demonstrate that glia cells need to be taken into account for successful GBM therapy development.