The association of tumor-expressed REG4, SPINK4 and alpha-1 antitrypsin with cancer-associated thrombosis in colorectal cancer.

Novel biomarkers are needed to improve current imperfect risk prediction models for cancer-associated thrombosis (CAT). We recently identified an RNA-sequencing profile that associates with CAT in colorectal cancer (CRC) patients, with REG4, SPINK4, and SERPINA1 as the top-3 upregulated genes at mRNA level. In the current study, we investigated whether protein expression of REG4, SPINK4 and alpha-1 antitrypsin (A1AT, encoded by SERPINA1) in the tumor associated with CAT in an independent cohort of CRC patients. From 418 patients with resected CRC, 18 patients who developed CAT were age, sex, and tumor stage-matched to 18 CRC patients without CAT. Protein expression was detected by immunohistochemical staining and scored blindly by assessing the H-score (percentage positive cells*scoring intensity). The association with CAT was assessed by means of logistic regression, using patients with an H-score below 33 as reference group. The odds ratios (ORs) for developing CAT for patients with A1AThigh, REG4high, SPINK4high tumors were 3.5 (95%CI 0.8-14.5), 2.0 (95%CI 0.5-7.6) and 2.0 (95%CI 0.5-7.4) when compared to A1ATlow, REG4low, SPINK4low, respectively. The OR was increased to 24.0 (95%CI 1.1-505.1) when two proteins were combined (A1AThigh/REG4high). This nested case-control study shows that combined protein expression of A1AT and REG4 associate with CAT in patients with colorectal cancer. Therefore, REG4/A1AT are potential biomarkers to improve the identification of patients with CRC who may benefit from thromboprophylaxis.

Initial report on distribution of ß3-adrenoceptor in the human female urethra.

INTRODUCTION: Past research has demonstrated that the urethral tonus is mainly under sympathetic control. Since 5 years, a beta 3-adrenoceptor (ADRB3) agonist is available in the treatment of overactive bladder syndrome. The presence of ADRB3 within the human urethra has not been demonstrated to date. Presence of ADRB3 in the urethra could influence urethral tonus. The aim of this study is to investigate the presence of ADRB3 in the human female urethra. MATERIAL AND METHODS: We performed anatomical studies in five female specimens. Three specimens were obtained from the body donation program, two from female patients with muscle-invasive bladder cancer, where radical resection of bladder and urethra was performed. The urethra up till the bladder neck was separated from the rest of the bladder and freshly obtained for this study. For demonstrating ADRB3 expression, we used rabbit polyclonal anti-human ADRB3 LS-A4198. RESULTS: Expression of ADBR3 was demonstrated in the epithelial layer of all urethral parts, except at the level of the meatus. The level of ADRB3 expression was highest in the mid urethra. There was no direct contact between ADRB3 and nerve tissue. ADRB3 expression was also demonstrated in the stratified muscle layer at the level of the external urethral sphincter. CONCLUSIONS: This is the first study to demonstrate the expression of ADRB3 in the human female urethra. There is an absence of a direct connection between ADRB3 and nerve tissue.

Role of Tissue Factor in Tumor Progression and Cancer-Associated Thrombosis.

It has been long-established that cancer and thrombosis are linked, but the exact underlying pathological mechanism remains to be unraveled. As the initiator of the coagulation cascade, the transmembrane glycoprotein tissue factor (TF) has been intensely investigated for its role in cancer-associated thrombosis and cancer progression. TF expression is regulated by both specific oncogenes and environmental factors, and it is shown to regulate primary growth and metastasis formation in a variety of cancer models. In clinical studies, TF has been shown to be overexpressed in most cancer types and is strongly associated with disease progression. While TF clearly associates with cancer progression, a prominent role for TF in the development of cancer-associated thrombosis is less clear. The current concept is that cancer-associated thrombosis is associated with the secretion of tumor-derived TF-positive extracellular vesicles in certain tumor types. To date, many therapeutic strategies to target TF-both in preclinical and clinical phase-are being pursued, including targeting TF or the TF:FVIIa complex by itself or by exploiting TF as a docking molecule to deliver cytotoxic compounds to the tumor. In this review, the authors summarize the current understanding of the role of TF in both cancer progression and cancer-associated thrombosis, and discuss novel insights on TF as a therapeutic target as well as a biomarker for cancer progression and VTE.

Movember GAP1 PDX project: An international collection of serially transplantable prostate cancer patient-derived xenograft (PDX) models.

BACKGROUND: While it has been challenging to establish prostate cancer patient-derived xenografts (PDXs), with a take rate of 10-40% and long latency time, multiple groups throughout the world have developed methods for the successful establishment of serially transplantable human prostate cancer PDXs using a variety of immune deficient mice. In 2014, the Movember Foundation launched a Global Action Plan 1 (GAP1) project to support an international collaborative prostate cancer PDX program involving eleven groups. Between these Movember consortium members, a total of 98 authenticated human prostate cancer PDXs were available for characterization. Eighty three of these were derived directly from patient material, and 15 were derived as variants of patient-derived material via serial passage in androgen deprived hosts. A major goal of the Movember GAP1 PDX project was to provide the prostate cancer research community with a summary of both the basic characteristics of the 98 available authenticated serially transplantable human prostate cancer PDX models and the appropriate contact information for collaborations. Herein, we report a summary of these PDX models. METHODS: PDX models were established in immunocompromised mice via subcutaneous or subrenal-capsule implantation. Dual-label species (ie, human vs mouse) specific centromere and telomere Fluorescence In Situ Hybridization (FISH) and immuno-histochemical (IHC) staining of tissue microarrays (TMAs) containing replicates of the PDX models were used for characterization of expression of a number of phenotypic markers important for prostate cancer including AR (assessed by IHC and FISH), Ki67, vimentin, RB1, P-Akt, chromogranin A (CgA), p53, ERG, PTEN, PSMA, and epithelial cytokeratins. RESULTS: Within this series of PDX models, the full spectrum of clinical disease stages is represented, including androgen-sensitive and castration-resistant primary and metastatic prostate adenocarcinomas as well as prostate carcinomas with neuroendocrine differentiation. The annotated clinical characteristics of these PDXs were correlated with their marker expression profile. CONCLUSION: Our results demonstrate the clinical relevance of this series of PDXs as a platform for both basic science studies and therapeutic discovery/drug development. The present report provides the prostate cancer community with a summary of the basic characteristics and a contact information for collaborations using these models.

Spontaneous bone metastases in a preclinical orthotopic model of invasive lobular carcinoma; the effect of pharmacological targeting TGFß receptor I kinase.

Invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) are the most frequently occurring histological subtypes of breast cancer, accounting for 80-90% and 10-15% of the total cases, respectively. At the time of diagnosis and surgical resection of the primary tumour, most patients do not have clinical signs of metastases, but bone micrometastases may already be present. Our aim was to develop a novel preclinical ILC model of spontaneous bone micrometastasis. We used murine invasive lobular breast carcinoma cells (KEP) that were generated by targeted deletion of E-cadherin and p53 in a conditional K14cre;Cdh1((F/F));Trp53((F/F)) mouse model of de novo mammary tumour formation. After surgical resection of the growing orthotopically implanted KEP cells, distant metastases were formed. In contrast to other orthotopic breast cancer models, KEP cells readily formed skeletal metastases with minimal lung involvement. Continuous treatment with SD-208 (60 mg/kg per day), an orally available TGFß receptor I kinase inhibitor, increased the tumour growth at the primary site and increased the number of distant metastases. Furthermore, when SD-208 treatment was started after surgical resection of the orthotopic tumour, increased bone colonisation was also observed (versus vehicle). Both our in vitro and in vivo data show that SD-208 treatment reduced TGFß signalling, inhibited apoptosis, and increased proliferation. In conclusion, we have demonstrated that orthotopic implantation of murine ILC cells represent a new breast cancer model of minimal residual disease in vivo, which comprises key steps of the metastatic cascade. The cancer cells are sensitive to the anti-tumour effects of TGFß. Our in vivo model is ideally suited for functional studies and evaluation of new pharmacological intervention strategies that may target one or more steps along the metastatic cascade of events.

Brown adipose tissue takes up plasma triglycerides mostly after lipolysis.

Brown adipose tissue (BAT) produces heat by burning TGs that are stored within intracellular lipid droplets and need to be replenished by the uptake of TG-derived FA from plasma. It is currently unclear whether BAT takes up FA via uptake of TG-rich lipoproteins (TRLs), after lipolysis-mediated liberation of FA, or via a combination of both. Therefore, we generated glycerol tri[(3)H]oleate and [(14)C]cholesteryl oleate double-labeled TRL-mimicking particles with an average diameter of 45, 80, and 150 nm (representing small VLDL to chylomicrons) and injected these intravenously into male C57Bl/6J mice. At room temperature (21°C), the uptake of (3)H-activity by BAT, expressed per gram of tissue, was much higher than the uptake of (14)C-activity, irrespective of particle size, indicating lipolysis-mediated uptake of TG-derived FA rather than whole particle uptake. Cold exposure (7°C) increased the uptake of FA derived from the differently sized particles by BAT, while retaining the selectivity for uptake of FA over cholesteryl ester (CE). At thermoneutrality (28°C), total FA uptake by BAT was attenuated, but the specificity of uptake of FA over CE was again largely retained. Altogether, we conclude that, in our model, BAT takes up plasma TG preferentially by means of lipolysis-mediated uptake of FA.

Liposomal delivery of dexamethasone attenuates prostate cancer bone metastatic tumor growth in vivo.

BACKGROUND: The inflammatory tumor microenvironment, and more specifically the tumor-associated macrophages, plays an essential role in the development and progression of prostate cancer towards metastatic bone disease. Tumors are often characterized by a leaky vasculature, which - combined with the prolonged circulation kinetics of liposomes - leads to efficient tumor localization of these drug carriers, via the so-called enhanced permeability and retention (EPR) -effect. In this study, we evaluated the utility of targeted, liposomal drug delivery of the glucocorticoid dexamethasone in a model of prostate cancer bone metastases. METHODS: Tumor-bearing Balb-c nu/nu mice were treated intravenously with 0.2-1.0-5.0 mg/kg/week free- and liposomal DEX for 3-4 weeks and tumor growth was monitored by bioluminescent imaging. RESULTS: Intravenously administered liposomes localize efficiently to bone metastases in vivo and treatment of established bone metastases with (liposomal) dexamethasone resulted in a significant inhibition of tumor growth up to 26 days after initiation of treatment. Furthermore, 1.0 mg/kg liposomal dexamethasone significantly outperformed 1.0 mg/kg free dexamethasone, and was found to be well-tolerated at clinically-relevant dosages that display potent anti-tumor efficacy. CONCLUSIONS: Liposomal delivery of the glucocorticoid dexamethasone inhibits the growth of malignant bone lesions. We believe that liposomal encapsulation of dexamethasone offers a promising new treatment option for advanced, metastatic prostate cancer which supports further clinical evaluation.

Venous Thromboembolism in Patients with Glioblastoma: Molecular Mechanisms and Clinical Implications.

Patients with glioblastoma are among the cancer patients with the highest risk of developing venous thromboembolism (VTE). Long-term thromboprophylaxis is not generally prescribed because of the increased susceptibility of glioblastoma patients to intracranial hemorrhage. This review provides an overview of the current clinical standard for glioblastoma patients, as well as the molecular and genetic background which underlies the high incidence of VTE. The two main procoagulant proteins involved in glioblastoma-related VTE, podoplanin and tissue factor, are described, in addition to the genetic aberrations that can be linked to a hypercoagulable state in glioblastoma. Furthermore, possible novel biomarkers and future treatment strategies are discussed, along with the potential of sequencing approaches toward personalized risk prediction for VTE. A glioblastoma-specific VTE risk stratification model may help identifying those patients in which the increased risk of bleeding due to extended anticoagulation is outweighed by the decreased risk of VTE.

The effects of an aggressive breast tumor on thrombosis after antithrombin downregulation in a hypercoagulable mouse model.

BACKGROUND: Despite improvements in therapy, breast cancer still contributes to high mortality rates. Survival of these patients becomes progressively worse upon diagnosis with cancer-associated thrombosis (CAT). Unfortunately, the mechanism causing CAT has remained unclear. OBJECTIVE: Set up an acute and non-invasive hypercoagulable mouse model with an aggressive breast cancer and study the mechanism of cancer-associated thrombosis. METHODS: Mice were grafted with the aggressive breast cancer cell line MDA-MB-231 or sham-treated. Subsequently, an acute imbalance in coagulation was introduced by injecting a synthetic small interfering (si) RNA targeting hepatic Serpinc1 to knockdown antithrombin - a condition known to predispose to cause a hypercoagulant state in vivo. RESULTS: Silencing Serpinc1 with siRNA decreased plasma antithrombin levels. siRNA treatment had no short-term effects on tumor characteristics, but increased distant metastasis within the timeframe of this study. The systemic pro-inflammatory status, with elevated platelet counts and fibrinogen levels in tumor-bearing mice, was also not affected by antithrombin silencing. While elevated fibrin deposition in the liver upon Serpinc1 targeting was not significantly affected by the presence of breast cancer, knockdown of antithrombin did significantly increase intratumoral fibrin deposition and inflammation. Surprisingly, in the presence of an aggressive tumor, a protective outcome with less clinical features coinciding with venous thrombosis were observed in mice with antithrombin knockdown. CONCLUSION: We conclude that the presence of a breast tumor protects hypercoagulant mice from severe consumption of coagulation factors after lowering hepatic antithrombin levels, possibly due to elevated platelet counts. However, the consequences on cancer-associated thrombosis remained inconclusive.

MicroRNAs as prognostic biomarkers for (cancer-associated) venous thromboembolism.

MicroRNAs (miRNAs) are small noncoding RNAs with gene regulatory functions and are commonly dysregulated in disease states. As miRNAs are relatively stable, easily measured, and accessible from plasma or other body fluids, they are promising biomarkers for the diagnosis and prediction of cancer and cardiovascular diseases. Venous thromboembolism (VTE) is the third most common cardiovascular disease worldwide with high morbidity and mortality. The suggested roles of miRNAs in regulating the pathophysiology of VTE and as VTE biomarkers are nowadays more evidenced. Patients with cancer are at increased risk of developing VTE compared to the general population. However, current risk prediction models for cancer-associated thrombosis (CAT) perform suboptimally, and novel biomarkers are therefore urgently needed to identify which patients may benefit the most from thromboprophylaxis. This review will first discuss how miRNAs mechanistically contribute to the pathophysiology of VTE. Next, the potential use of miRNAs as predictive biomarkers for VTE in subjects without cancer is reviewed, followed by an in-depth focus on CAT. Several of the identified miRNAs in CAT were found to be differentially regulated in VTE as well, giving clues on the pathophysiology of CAT. We propose that subsequent studies should be adequately sized to determine which panel of miRNAs best predicts VTE and CAT. Thereafter, validation studies using comparable patient populations are required to ultimately unveil whether miRNAs-as standalone or incorporated into existing risk models-are promising valuable VTE and CAT biomarkers.

Temozolomide and Lomustine Induce Tissue Factor Expression and Procoagulant Activity in Glioblastoma Cells In Vitro.

Glioblastoma (GBM) patients have one of the highest risks of venous thromboembolism (VTE), which is even further increased upon treatment with chemotherapy. Tissue factor (TF) is the initiator of the extrinsic coagulation pathway and expressed by GBM cells. In this study, we aimed to examine the effect of routinely used chemotherapeutic agents Temozolomide (TMZ) and Lomustine (LOM) on TF procoagulant activity and expression in GBM cells in vitro. Three human GBM cell lines (U-251, U-87, U-118) were exposed to 100 µM TMZ or 30 µM LOM for 72 h. TF procoagulant activity was assessed via an FXa generation assay and TF gene and protein expression through qPCR and Western blotting. The externalization of phosphatidylserine (PS) was studied using Annexin V flow cytometry. Treatment with TMZ and LOM resulted in increased procoagulant activity in all cell lines. Furthermore, both agents induced procoagulant activity in the supernatant and tumor-cell-secreted extracellular vesicles. In line, TF gene and protein expression were increased upon TMZ and LOM treatment. Additionally, PS externalization and induction of inflammatory-associated genes were observed. Overall, the chemotherapeutic modalities TMZ and LOM induced procoagulant activity and increased TF gene and protein expression in all GBM cell lines tested, which may contribute to the increased VTE risk observed in GBM patients undergoing chemotherapy.

Targeted DNA sequencing to identify genetic aberrations in glioblastoma that underlie venous thromboembolism; a cohort study.

BACKGROUND AND OBJECTIVES: Patients with glioblastoma have a high risk of developing venous thromboembolism (VTE). However, the role of underlying genetic risk factors remains largely unknown. Therefore, the aim of this study was to discover whether genetic aberrations in glioblastoma associate with VTE risk. METHODS: In this cohort study, all consecutive patients diagnosed with glioblastoma in two Dutch hospitals between February 2017 and August 2020 were included. Targeted DNA next-generation sequencing of all glioblastomas was performed for diagnostic purposes and included mutational status of the genes ATRX, BRAF, CIC, FUBP1, H3F3A, IDH1, IDH2, PIK3CA, PTEN and TP53 and amplification/gain or deletion of BRAF, CDKN2A, EGFR, NOTCH1 and PTEN. The primary outcome was VTE within three months before glioblastoma diagnosis until two years after. Cumulative incidences were determined using competing risk analysis adjusting for mortality. Univariable Cox regression analysis was performed to determine hazard ratios. RESULTS: From 324 patients with glioblastoma, 25 were diagnosed with VTE. Patients with a CDKN2A deletion had a 12-month adjusted cumulative incidence of VTE of 12.5 % (95%CI: 7.3-19.3) compared with 5.4 % (95%CI: 2.6-9.6) in patients with CDKN2A wildtype (p = 0.020), corresponding to a HR of 2.53 (95%CI: 1.12-5.73, p = 0.026). No significant associations were found between any of the other investigated genes and VTE. CONCLUSION: This study suggests a potential role for CDKN2A deletion in glioblastoma-related VTE. Therefore, once independently validated, CDKN2A mutational status may be a promising predictor to identify glioblastoma patients at high risk for VTE, who may benefit from thromboprophylaxis.

RNA-sequencing to discover genes and signaling pathways associated with venous thromboembolism in glioblastoma patients: A case-control study.

BACKGROUND: Glioblastoma patients are at high risk of developing venous thromboembolism (VTE). Tumor-intrinsic features are considered to play a role, but the underlying pathophysiological mechanisms remain incompletely understood. OBJECTIVES: To identify tumor-expressed genes and signaling pathways that associate with glioblastoma-related VTE by using next generation RNA-sequencing (RNA-Seq). METHODS: The tumor gene expression profile of 23 glioblastoma patients with VTE and 23 glioblastoma patients without VTE was compared using an unpaired analysis. Ingenuity Pathway Analysis (IPA) core analysis was performed on the top 50 differentially expressed genes to explore associated functions and pathways. Based on full RNA-Seq data, molecular glioblastoma subtypes were determined by performing cluster analysis. RESULTS: Of the 19,327 genes, 1246 (6.4 %) were differentially expressed between glioblastoma patients with and without VTE (unadjusted P < 0.05). The most highly overexpressed gene was GLI1, a classical target gene in the Sonic Hedgehog (Shh) signaling pathway (log2 fold change: 3.7; unadjusted P < 0.0001, adjusted P = 0.219). In line, Shh signaling was among the top canonical pathways and processes associated with VTE. The proportion of patients with the proneural/neural glioblastoma subtype was higher among those with VTE than controls. CONCLUSION: Shh signaling may be involved in the development of glioblastoma-related VTE.

Tumor-expressed factor VII is associated with survival and regulates tumor progression in breast cancer.

Cancer enhances the risk of venous thromboembolism, but a hypercoagulant microenvironment also promotes cancer progression. Although anticoagulants have been suggested as a potential anticancer treatment, clinical studies on the effect of such modalities on cancer progression have not yet been successful for unknown reasons. In normal physiology, complex formation between the subendothelial-expressed tissue factor (TF) and the blood-borne liver-derived factor VII (FVII) results in induction of the extrinsic coagulation cascade and intracellular signaling via protease-activated receptors (PARs). In cancer, TF is overexpressed and linked to poor prognosis. Here, we report that increased levels of FVII are also observed in breast cancer specimens and are associated with tumor progression and metastasis to the liver. In breast cancer cell lines, tumor-expressed FVII drives changes reminiscent of epithelial-to-mesenchymal transition (EMT), tumor cell invasion, and expression of the prometastatic genes, SNAI2 and SOX9. In vivo, tumor-expressed FVII enhanced tumor growth and liver metastasis. Surprisingly, liver-derived FVII appeared to inhibit metastasis. Finally, tumor-expressed FVII-induced prometastatic gene expression independent of TF but required a functional endothelial protein C receptor, whereas recombinant activated FVII acting via the canonical TF:PAR2 pathway inhibited prometastatic gene expression. Here, we propose that tumor-expressed FVII and liver-derived FVII have opposing effects on EMT and metastasis.

Integrin αv expression is required for the acquisition of a metastatic stem/progenitor cell phenotype in human prostate cancer.

Integrins participate in multiple cellular processes, including cell adhesion, migration, proliferation, survival, and the activation of growth factor receptors. Recent studies have shown that expression of αv integrins is elevated in the prostate cancer stem/progenitor cell subpopulation compared with more differentiated, committed precursors. Here, we examine the functional role of αv integrin receptor expression in the acquisition of a metastatic stem/progenitor phenotype in human prostate cancer. Stable knockdown of αv integrins expression in PC-3M-Pro4 prostate cancer cells coincided with a significant decrease of prostate cancer stem/progenitor cell characteristics (α2 integrin, CD44, and ALDH(hi)) and decreased expression of invasion-associated genes Snail, Snail2, and Twist. Consistent with these observations, αv-knockdown strongly inhibited the clonogenic and migratory potentials of human prostate cancer cells in vitro and significantly decreased tumorigenicity and metastatic ability in preclinical models of orthotopic growth and bone metastasis. Our data indicate that integrin αv expression is functionally involved in the maintenance of a highly migratory, mesenchymal cellular phenotype as well as the acquisition of a stem/progenitor phenotype in human prostate cancer cells with metastasis-initiating capacity.

Tumor-expressed microRNAs associated with venous thromboembolism in colorectal cancer.

Background: Colorectal cancer patients have an increased risk of developing venous thromboembolism (VTE), resulting in increased morbidity and mortality. Because the exact mechanism is yet unknown, risk prediction is still challenging; therefore, new biomarkers are needed. MicroRNAs (miRNAs) are small, relatively stable RNAs, that regulate a variety of cellular processes, and are easily measured in body fluids. Objective: The aim of this study was to identify novel tumor-expressed miRNAs associated with VTE. Methods: In a cohort of 418 colorectal cancer patients diagnosed between 2001 and 2015 at the Leiden University Medical Center, 23 patients (5.5%) developed VTE 1 year before or after cancer diagnosis. Based on availability of frozen tumor material, tumor cells of 17 patients with VTE and 18 patients without VTE were isolated using laser capture microdissection and subsequently analyzed on the Illumina sequencing platform NovaSeq600 using 150-bp paired-end sequencing. Cases and controls were matched on age, sex, tumor stage, and grade. Differential miRNA expression was analyzed using edgeR. Results: A total of 547 miRNAs were detected. Applying a 1.5-fold difference and false discovery rate of <0.1, 19 tumor-miRNAs were differentially regulated in VTE cases versus controls, with hsa-miR-3652, hsa-miR-92b-5p, and hsa-miR-10,394-5p as most significantly downregulated. Seven of the 19 identified miRNAs were predicted to regulate the gonadotropin-releasing hormone receptor pathway. Conclusion: We identified 19 differentially regulated tumor-expressed miRNAs in colorectal cancer-associated VTE, which may provide insights into the biological mechanism and in the future might have potential to serve as novel, predictive biomarkers.

Incidence and determinants of thrombotic and bleeding complications in patients with glioblastoma.

BACKGROUND: Glioblastoma patients are considered to be at high risk of venous thromboembolism (VTE) and major bleeding (MB), although reliable incidence estimates are lacking. Moreover, the risk of arterial thromboembolism (ATE) in these patients is largely unknown. Our aim was to assess the cumulative incidence, predictors, and prognostic impact of VTE, ATE, and MB on subsequent complications and mortality. METHODS: Cohort study of 967 consecutive patients diagnosed with glioblastoma between 2004-2020 in two hospitals. Patients were followed from 6 months before date of histopathological glioblastoma diagnosis up to 2 years after, or until an outcome of interest (VTE, ATE, and MB) or death occurred, depending on the analysis. Cumulative incidences were estimated with death as competing risk. Cox regression was used to identify predictors and the prognostic impact. RESULTS: A total of 101 patients were diagnosed with VTE, 50 with ATE, and 126 with MB during a median follow-up of 15 months (interquartile range 9.0-22). The adjusted 1-year cumulative incidence of VTE was 7.5% (95% confidence interval [CI] 5.9-9.3), of ATE 4.1% (95% CI 3.0-5.6), and of MB 12% (95% CI 9.6-14). Older age, type of surgery, and performance status were predictors of VTE. Incident VTE during follow-up was associated with MB (adjusted HR 4.7, 95% CI 2.5-9.0). MB and VTE were associated with mortality (adjusted HR 1.7, 95% CI 1.3-2.1 and 1.3, 95% CI 1.0-1.7, respectively). CONCLUSION: We found considerable incidences of VTE and MB in glioblastoma patients, with both complications associated with poorer prognosis. Our observations emphasize the need for prospective studies to determine optimal thromboprophylaxis and VTE treatment strategy in these patients.

Prevalence, Treatment, and Prognosis of Tumor Thrombi in Renal Cell Carcinoma.

Background: Renal cell carcinoma (RCC) can be complicated by a venous tumor thrombus (TT), of which the optimal management is unknown. Objectives: This study sought to assess the prevalence of TT in RCC, its current management, and its association with venous thromboembolism (VTE), arterial thromboembolism (ATE), major bleeding (MB), and mortality. Methods: Patients diagnosed with RCC between 2010 and 2019 in our hospital were included and followed from RCC diagnosis until 2 years after, or until an outcome of interest (VTE, ATE, and MB) or death occurred, depending on the analysis. Cumulative incidences were estimated with death as a competing risk. Cause-specific hazard models were used to identify predictors and the prognostic impact. Results: Of the 647 patients, 86 had a TT (prevalence 13.3%) at RCC diagnosis, of which 34 were limited to the renal vein, 37 were limited to the inferior vena cava below the diaphragm, and 15 extended above the diaphragm; 20 patients started therapeutic anticoagulation and 45 underwent thrombectomy with/without anticoagulation. During follow-up (median 24.0 [IQR: 7.0-24.0] months), 17 TT patients developed a VTE, 0 developed an ATE, and 11 developed MB. TT patients were more often diagnosed with VTE (adjusted HR: 6.61; 95% CI: 3.18-13.73) than non-TT patients, with increasing VTE risks in more proximal TT levels. TT patients receiving anticoagulation still developed VTE (HR: 0.56; 95% CI: 0.13-2.48), at the cost of more MB events (HR: 3.44; 95% CI: 0.95-12.42) compared with those without anticoagulation. Conclusions: Patients with RCC-associated TT were at high risk of developing VTE. Future studies should establish which of these patients benefit from anticoagulation therapy.

A systematic review on the effects of direct oral anticoagulants on cancer growth and metastasis in animal models.

BACKGROUND: Direct oral anticoagulants (DOACs) are now the first choice thromboprophylaxis in cancer patients who do not have a high risk of bleeding. In addition to the anticoagulant effects, potential anti-tumor effects of DOACs have also been studied in animal cancer models. In this study, we summarize the effects of DOACs on cancer growth and metastasis in animal models through a systematic review with a qualitative analysis. METHODS: PubMed, EMBASE and Web of Science were systematically searched for original studies that describe animal models of cancer in which one of the experimental groups received DOAC monotherapy, and which reported quantitatively on primary tumor or metastases. RESULTS: Nine studies - reporting a total of 19 animal experiments - met the inclusion criteria. These 19 experiments included spontaneous cancer (n = 2), carcinogenicity (n = 2), xenograft (n = 7) and syngeneic (n = 8) models, encompassing orthotopic (n = 7), subcutaneous (n = 5), intraperitoneal (n = 1) and intravenous (n = 2) injection of cancer cells and included treatments with the DOACs ximelagatran (n = 4), dabigatran etexilate (n = 6) and/or rivaroxaban (n = 11). DOAC treatment decreased tumor growth at implanted and metastatic site in 18.8% (3/16) and 20.0% (3/15) of the experiments, respectively. Conversely, DOACs increased tumor growth at implanted and metastatic site in 6.3% (1/16) and 20.0% (3/15) of the experiments, respectively. CONCLUSION: DOAC monotherapy resulted in neoplastic changes in a rat carcinogenicity study, showed a lack of effect in mouse xenograft models, while the effect on cancer growth and metastasis in mouse syngeneic models depended on the timing of DOAC treatment and type of cancer model used.

Genes and proteins associated with the risk for cancer-associated thrombosis.

Cancer patients have a four- to sevenfold increased risk of developing cancer-associated thrombosis (CAT), which is associated with a strong increase in morbidity and mortality. Not all cancer patients receive thromboprophylaxis as this may lead to adverse events in a cancer population that is already at increased risk for major bleedings. Different risk prediction models have been developed to identify cancer patients at high risk of developing CAT that may be selected for thromboprophylaxis. However, risk models using the currently established biomarkers and clinical parameters perform poorly, particularly when validated in independent cohorts. Discovery of new and better biomarkers are therefore urgently needed. This review describes how aberrations in the genetic profile of the tumor and host influence a hypercoagulable state, and explores how these can be used as novel biomarker to improve CAT risk prediction.