Caroline J. Reddel

The high occurrence of cancer-associated thrombosis is associated with elevated thrombin generation. Tumour cells increase the potential for thrombin generation both directly, through the expression and release of procoagulant factors, and indirectly, through signals that activate other cell types (including platelets, leukocytes and erythrocytes). Furthermore, cancer treatments can worsen these effects. Coagulation factors, including tissue factor, and inhibitors of coagulation are altered and extracellular vesicles (EVs), which can promote and support thrombin generation, are released by tumour and other cells. Some phosphatidylserine-expressing platelet subsets and platelet-derived EVs provide the surface required for the assembly of coagulation factors essential for thrombin generation in vivo. This review will explore the causes of increased thrombin production in cancer, and the availability and utility of tests and biomarkers. Increased thrombin production not only increases blood coagulation, but also promotes tumour growth and metastasis and as a consequence, thrombin and its contributors present opportunities for treatment of cancer-associated thrombosis and cancer itself.

Summary Introduction Studies have shown dabigatran to be an effective anticoagulant with an acceptable bleeding profile. None the less, these patients do suffer from bleeding complications. Unfortunately, there are currently no direct reversal agents to dabigatran or established guidelines on the management of bleeding in these circumstances. Methods We examined the effects on thrombin generation parameters, after ex‐vivo spiking the plasma of patients on dabigatran ( n = 8) with FEIBA ® . These parameters were measured using the calibrated automated thrombography ( CAT ) machine. Results In our study, we showed the ability of FEIBA ® to improve the abnormal thrombin generation parameters caused by dabigatran in these patients. Conclusion This provides evidence, lacking in the literature, that this agent may be able to provide haemostatic support in situations where dabigatran induced coagulopathy exists.

<h3>Abstract</h3> Dengue virus, a single-stranded positive sense RNA virus, is the most prevalent mosquito-borne pathogen in the world. Like all RNA viruses, it uses conserved structural elements within its genome to control essential replicative steps. A 70 nucleotides stem-loop RNA structure (called SLA) found at the 5’-end of the genome of all flaviviruses, functions as the promoter for viral replication. This highly conserved structure interacts with the viral polymerase NS5 to initiate RNA synthesis. Here we report the NMR structure of a monomeric SLA from Dengue virus serotype 1, assembled to high-resolution from independently folded structural elements. The DENV1 SLA has an L-shape structure, where the top and side helices are coaxially-stacked and the bottom helix is roughly perpendicular to them. Because the sequence is highly conserved among different flavivirus genomes, it is likely that the three-dimensional fold and local structure of SLA are also conserved among flaviviruses and required for efficient replication. This work provides structural insight into the Dengue promoter and provides the foundation for the discovery of new antiviral drugs that target this essential replicative step.