Thrombosis and cancer

Neutrophil Extracellular Traps: Villains and Targets in Arterial, Venous, and Cancer-Associated Thrombosis

Recent studies have demonstrated a role of neutrophils in both venous and arterial thrombosis. A key prothrombotic feature of neutrophils is their ability to release web-like structures composed of DNA filaments coated with histones and granule proteins referred to as neutrophil extracellular traps (NETs). NETs were discovered over a decade ago as part of our first line of host defense against invading microorganisms. Although NETs have a protective role against pathogens, recent data suggest that an uncontrolled and excessive NET formation within the vasculature may contribute to pathological thrombotic disorders. In vitro studies suggest that NETs promote vessel occlusion by providing a scaffold for platelets, red blood cells, extracellular vesicles, and procoagulant molecules, such as von Willebrand factor and tissue factor. In addition, NET components enhance coagulation by both activating the intrinsic pathway and degrading an inhibitor of the extrinsic pathway (tissue factor pathway inhibitor). NET formation has, therefore, been proposed to contribute to thrombus formation and propagation in arterial, venous, and cancer-associated thrombosis. This review will describe animal and human studies suggesting a role of NETs in the pathogenesis of various thrombotic disorders. Targeting NETs may be a novel approach to reduce thrombosis without affecting hemostasis.

Augmentation of EPR Effect and Efficacy of Anticancer Nanomedicine by Carbon Monoxide Generating Agents

One obstacle to the successful delivery of nanodrugs into solid tumors is the heterogeneity of an enhanced permeability and retention (EPR) effect as a result of occluded or embolized tumor blood vessels. Therefore, the augmentation of the EPR effect is critical for satisfactory anticancer nanomedicine. In this study, we focused on one vascular mediator involved in the EPR effect, carbon monoxide (CO), and utilized two CO generating agents, one is an extrinsic CO donor (SMA/CORM2 micelle) and another is an inducer of endogenous CO generation via heme oxygenase-1 (HO-1) induction that is carried out using pegylated hemin. Both agents generated CO selectively in solid tumors, which resulted in an enhanced EPR effect and a two- to three-folds increased tumor accumulation of nanodrugs. An increase in drug accumulation in the normal tissue did not occur with the treatment of CO generators. In vivo imaging also clearly indicated a more intensified fluorescence of macromolecular nanoprobe in solid tumors when combined with these CO generators. Consequently, the combination of CO generators with anticancer nanodrugs resulted in an increased anticancer effect in the different transplanted solid tumor models. These findings strongly warrant the potential application of these CO generators as EPR enhancers in order to enhance tumor detection and therapy using nanodrugs.

Biology and Role of Extracellular Vesicles (EVs) in the Pathogenesis of Thrombosis

Extracellular vesicles (EVs) are well-established mediators of cell-to-cell communication. EVs can be released by every cell type and they can be classified into three major groups according to their biogenesis, dimension, density, and predominant protein markers: exosomes, microvesicles, and apoptotic bodies. During their formation, EVs associate with specific cargo from their parental cell that can include RNAs, free fatty acids, surface receptors, and proteins. The biological function of EVs is to maintain cellular and tissue homeostasis by transferring critical biological cargos to distal or neighboring recipient cells. On the other hand, their role in intercellular communication may also contribute to the pathogenesis of several diseases, including thrombosis. More recently, their physiological and biochemical properties have suggested their use as a therapeutic tool in tissue regeneration as well as a novel option for drug delivery. In this review, we will summarize the impact of EVs released from blood and vascular cells in arterial and venous thrombosis, describing the mechanisms by which EVs affect thrombosis and their potential clinical applications.

Oncogenic Regulation of Extracellular Vesicle Proteome and Heterogeneity

Mutational and epigenetic driver events profoundly alter intercellular communication pathways in cancer. This effect includes deregulated release, molecular composition, and biological activity of extracellular vesicles (EVs), membranous cellular fragments ranging from a few microns to less than 100 nm in diameter and filled with bioactive molecular cargo (proteins, lipids, and nucleic acids). While EVs are usually classified on the basis of their physical properties and biogenetic mechanisms, recent analyses of their proteome suggest a larger than expected molecular diversity, a notion that is also supported by multicolour nano-flow cytometry and other emerging technology platforms designed to analyze single EVs. Both protein composition and EV diversity are markedly altered by oncogenic transformation, epithelial to mesenchymal transition, and differentiation of cancer stem cells. Interestingly, only a subset of EVs released from mutant cells may carry oncogenic proteins (e.g., EGFRvIII), hence, these EVs are often referred to as "oncosomes". Indeed, oncogenic transformation alters the repertoire of EV-associated proteins, increases the presence of pro-invasive cargo, and alters the composition of distinct EV populations. Molecular profiling of single EVs may reveal a more intricate effect of transforming events on the architecture of EV populations in cancer and shed new light on their biological role and diagnostic utility.

Echocardiographic measures associated with the presence of left ventricular thrombus in patients with chemotherapy-related cardiac dysfunction

BACKGROUND

Previous studies have not evaluated the prevalence and specific risk factors for the development of left ventricular (LV) thrombus in patients with severely reduced left ventricular dysfunction due to chemotherapy-related cardiomyopathy. We sought to evaluate the prevalence and potential markers of LV thrombus in this patient population.

METHODS

From January 2009 to December 2013, patients with chemotherapy-related severe LV dysfunction (LV ejection fraction [LVEF] ≤ 30%) identified from MD Anderson Cancer Center database were reviewed. Patient characteristics and echocardiographic parameters were analyzed to determine potential risk factors for LV thrombus.

RESULTS

A total of 121 patients met inclusion criteria (age 54.8 ± 15.2 years; female 63.6%; LVEF 26.3 ± 4%). LV thrombus was present in 9 patients (7.4%). Patients with LV thrombus have significantly lower LVEF compared to those without (18.7 ± 3.8% vs 26.9 ± 3.4%, P < .0001). Prevalence of LV thrombus increased as LVEF decreased and was the highest in patients with LVEF < 20%. By univariate analysis, decreased LVEF, particularly LVEF < 20% (OR 36.30, 95% CI 7.35-179.25, P < .0001) and restrictive LV filling pattern (OR 18.13, 95% CI 4.17-78.89, P = .0001) were associated with presence of LV thrombus.

CONCLUSION

In patients with severely reduced LV systolic function due to chemotherapy-induced cardiomyopathy, LV thrombus was found in 7.4% of subjects. Severely decreased LVEF (<20%) and restrictive LV filling pattern were associated with the presence of LV thrombus.

Human cancer cells suppress behaviors of endothelial progenitor cells through miR-21 targeting IL6R

Deep vein thrombosis (DVT) is a severe clinical process and has a high rate of fatality. Cancer patients have a high incidence rate of venous thrombosis complication and increase the mortality of cancer patients for 2-8 times. The mechanisms involved in human cancers and venous thrombosis remains unclear. In this study, we determined miR-21 expressed higher in human breast cancer, colon cancer and hepatocellular cancer tissues compared with normal tissues and expressed higher in exosomes of breast cancer and hepatocellular cancer cell lines compared with normal cells. MiR-21 dramatically suppressed proliferation, migration and invasion of endothelial progenitor cells (EPCs), which performed promoting role in thrombus repairment and resolution. High levels of miR-21 in exosomes of human cancers dramatically inhibited behaviors of EPCs, and depletion of miR-21 abrogated the decreased proliferation, migration and invasion of EPCs induced by human cancer cells. Moreover, IL6R (interleukin 6 receptor) was identified to be a direct target of miR-21 and promoted cell proliferation, migration and invasion of EPCs. Therefore, the miR-21-IL6R pathway contributed to behaviors of EPCs and consequently mediated the vein thrombosis in patients with cancer. MiR-21-IL6R pathway based therapeutic methods would be beneficial to decrease the complicated venous thrombosis in cancer patients and promote thrombus resolution.

Analysis of preoperative blood platelet parameters in terms of diversity of epithelial ovarian cancer

Smouldering inflammation, thrombocytosis, and platelet hyper-reactivity are linked to malignancy. The relationships between preoperative diagnostic blood morphology parameters and cancer have been the focus of much interest, because some of these parameters are correlated with advanced cancer stages and poor patient survival rates. This study aimed to perform an observational, retrospective analysis of the intradiversity of blood platelet parameters in patients with different International Federation of Gynaecology and Obstetrics (FIGO) stages and different histological types of epithelial ovarian carcinomas (EOC), and also an analysis of the overall survival rate.In all, 94 EOC patients were included in this analysis (23 mucinous, 33 serous, 20 undifferentiated, 14 endometrioid, and 4 clear cell carcinoma cases). Peripheral blood samples were collected and analyzed before drug or surgical treatment.The platelet-to-neutrophil ratio (PNR) was related to the histological type of EOC, particularly mucinous carcinoma. In patients with mucinous cancer, the PNR was significantly lower compared with patients with nonmucinous cancer, and this parameter distinguished between mucinous and nonmucinous groups of patients (area under receiver-operating characteristic [ROC] curve 0.721 ± .056; sensitivity 82.6%; specificity 61%; P < .001; ROC analysis), regardless of the FIGO stage. Moreover, elevated PNR values were correlated with lower survival rate of EOC patients.The reduced PNR, similar to the lower level of cancer antigen 125, is characteristic for mucinous ovarian carcinoma patients. Moreover, elevated PNR index might correlate with poor survival of patients.

Mutations in Coagulation Factor VIII Are Associated with More Favorable Outcome in Patients with Cutaneous Melanoma

Coagulation factor VIII (FVIII), von Willebrand factor (VWF), and ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats 13) play an important role in the regulation of normal hemostasis. However, little is known about their roles in patients with malignancy, particularly with cutaneous melanoma. Whole genome sequencing data are available for 25,719 cases in 126 cancer genomic studies for analysis. All sequencing data and corresponding pathology findings were obtained from The Cancer Genome Atlas. The cBioPortal bioinformatics tools were used for the data analysis. Our results demonstrated that mutations in genes encoding FVIII , VWF , and ADAMTS13 were reported in 92 of 126 cancer genomic studies, and high mutation rates in these three genes were observed in patients with cutaneous melanoma from three independent studies. Moreover, high mutation rates in FVIII , VWF , and ADAMTS13 were also found in patients with diffuse large B cell lymphoma (22.9%), lung small cell carcinoma (20.7%), and colon adenocarcinoma (19.4%). Among 366 melanoma cases from TCGA provisional, the somatic mutation rates of FVIII , VWF , and ADAMTS13 in tumor cells were 15, 14, and 5%, respectively. There was a strong tendency for coexisting mutations of FVIII , VWF , and ADAMTS13 . Kaplan–Meier survival analysis demonstrated that melanoma patients with FVIII mutations had a more favorable overall survival rate than those without FVIII mutations ( p  = 0.02). These findings suggest, for the first time, that the FVIII mutation burden may have a prognostic value for patients with cutaneous melanoma. Further studies are warranted to delineate the molecular mechanisms underlying the favorable prognosis associated with FVIII mutations.

Incidence of venous thromboembolism following the neoadjuvant chemotherapy regimen for epithelial type of ovarian cancer

This study aims to analyze the risk of venous thromboembolism (VTE) in patients receiving neoadjuvant chemotherapy (NACT) for epithelial ovarian cancer (EOC).A retrospective audit was conducted examining 147 patients treated for EOC. Surgical treatment with curative intent, with or without NACT and adjuvant chemotherapy, is the treatment approach, which was modified according to the patient's condition. The incidence of VTE with the most commonly used chemotherapy regimen, carboplatin, cisplatin, paclitaxel, docetaxel, and others were evaluated.This study found a 13.6% incidence of VTE in patients undergoing therapy with curative intent for EOC. No association was seen between NACT and VTE compared to VTE after standard treatment: 2/16 (12.5%) vs 5/131 (3.8%) (P = .16). Univariate and multivariate analyses also demonstrated that NACT has no risk for VTE with odds ratio (OR) = 0.89 (95% CI = 0.18-4.28) and P = 1. Results did not vary significantly with the type of chemotherapy used. Furthermore, increased incidence of VTE as an incidental finding supports the well-established role of malignancy in VTE occurrence. Univariate and multivariate analyses demonstrated that VTE occurred more frequently in menopausal women than nonmenopausal women (17.9% vs 5.8%) with OR = 3.55 (95% CI = 0.99-12.78) and P = .04 in patients aged ≥60 (19.3% vs 10%) with OR = 2.15 (95% CI = 0.83-5.57) and P = .13 but is not statistically significant.We conclude that NACT has no association with VTE and the currently used common chemotherapeutic drug combinations for ovarian cancer carry the minimal risk of thromboembolic events.

Hypoxia in Gliomas: Opening Therapeutical Opportunities Using a Mathematical-Based Approach

This chapter explores the use of mathematical models as promising and powerful tools to understand the complexity of tumors and their, frequently, hypoxic environment. We focus on gliomas, which are primary brain tumors derived from glial cells, mainly astrocytes and/or oligodendrocytes. A variety of mathematical models, based on ordinary and/or partial differential equations, have been developed both at the micro and macroscopic levels. The aim here is to describe in a quantitative way key physiopathological mechanisms relevant in these types of malignancies and to suggest optimal therapeutical strategies. More specifically, we consider novel therapies targeting thromboembolic phenomena to decrease cell invasion in high grade glioma or to delay the malignant transformation in low grade gliomas. This study has been the basis of a multidisciplinary collaboration involving, among others, neuro-oncologists, radiation oncologists, pathologists, cancer biologists, surgeons and mathematicians.

Subgroup Analysis of Patients with Cancer in XALIA: A Noninterventional Study of Rivaroxaban versus Standard Anticoagulation for VTE

Background  The noninterventional XALIA study compared rivaroxaban with standard anticoagulation for deep vein thrombosis treatment. This substudy describes the demographics, clinical characteristics, and outcomes of the patients with cancer.

Methods  Therapy type, dose, and duration were at the physician's discretion. The cohorts identified were rivaroxaban (rivaroxaban alone or after heparin or fondaparinux for ≤48 hours); early switchers (rivaroxaban after heparin or fondaparinux for >48 hours to 14 days and/or a vitamin K antagonist [VKA] for 1–14 days); standard anticoagulation (heparin or fondaparinux and a VKA); low-molecular-weight heparin (LMWH) alone; and miscellaneous (other heparins, fondaparinux alone, VKA alone). Primary outcomes were major bleeding, recurrent venous thromboembolism, and all-cause mortality.

Results  In XALIA, 587 patients (11.4% of the XALIA cohort) were with cancer: 146 (24.9%) rivaroxaban, 30 (5.1%) early switchers, 141 (24.0%) standard anticoagulation, 223 (38.0%) LMWH, and 47 (8.0%) miscellaneous. Patients with gastrointestinal or lung cancer more commonly received LMWH than rivaroxaban; the opposite occurred in patients with breast or genitourinary cancer. Rates of primary outcome in the rivaroxaban group were as follows: major bleeding, 1.4% ( n  = 2); recurrent venous thromboembolism, 3.4% ( n  = 5); and all-cause mortality, 4.8% ( n  = 7).

Conclusion  In XALIA, physicians treated cancer-associated thrombosis with various anticoagulant regimens, most commonly LMWH. In addition, the choice of anticoagulant varied with cancer type. In rivaroxaban-treated patients, rates for the primary outcomes were low, suggesting that patients administered rivaroxaban were a good prognosis group.

First US experience with Pipeline Flex with Shield Technology using aspirin as antiplatelet monotherapy

Flow diversion has revolutionised the treatment of intracranial aneurysms, and the Pipeline Embolization Device (PED) remains the only flow diverter (FD) approved in the USA. However, thromboembolic events remain an issue for FDs. Attempting to minimise these incidents, a newer PED has been developed with the use of covalent bonding of phosphorylcholine onto the Pipeline device that has been known as Shield Technology (PED Shield), which in vitro has demonstrated a significant reduction in material thrombogenicity. We report the first US experience of the PED Shield in the treatment of a ruptured fusiform aneurysm located in the right vertebral artery in an attempt to mitigate complications related to the use of dual-antiplatelet therapy and discuss our rationale for using the new FD, using aspirin only as the antiplatelet regimen.

Thrombin-unique coagulation system protein with multifaceted impacts on cancer and metastasis

The association between blood coagulation and cancer development is well recognized. Thrombin, the pleiotropic enzyme best known for its contribution to fibrin formation and platelet aggregation during vascular hemostasis, may also trigger cellular events through protease-activated receptors, PAR-1 and PAR-4, leading to cancer progression. Our pioneering findings provided evidence that thrombin contributes to cancer metastasis by increasing adhesive potential of malignant cells. However, there is evidence that thrombin regulates every step of cancer dissemination: (1) cancer cell invasion, detachment from primary tumor, migration; (2) entering the blood vessel; (3) surviving in vasculature; (4) extravasation; (5) implantation in host organs. Recent studies have provided new molecular data about thrombin generation in cancer patients and the mechanisms by which thrombin contributes to transendothelial migration, platelet/tumor cell interactions, angiogenesis, and other processes. Though a great deal is known regarding the role of thrombin in cancer dissemination, there are new data for multiple thrombin-mediated events that justify devoting focus to this topic with a comprehensive approach.

Extracellular vesicle communication pathways as regulatory targets of oncogenic transformation

Pathogenesis of human cancers bridges intracellular oncogenic driver events and their impact on intercellular communication. Among multiple mediators of this 'pathological connectivity' the role of extracellular vesicles (EVs) and their subsets (exosomes, ectosomes, oncosomes) is of particular interest for several reasons. The release of EVs from cancer cells represents a unique mechanism of regulated expulsion of bioactive molecules, a process that also mediates cell-to-cell transfer of lipids, proteins, and nucleic acids. Biological effects of these processes have been implicated in several aspects of cancer-related pathology, including tumour growth, invasion, angiogenesis, metastasis, immunity and thrombosis. Notably, the emerging evidence suggests that oncogenic mutations may impact several aspects of EV-mediated cell-cell communication including: (i) EV release rate and protein content; (ii) molecular composition of cancer EVs; (iii) the inclusion of oncogenic and mutant macromolecules in the EV cargo; (iv) EV-mediated release of genomic DNA; (v) deregulation of mechanisms responsible for EV biogenesis (vesiculome) and (vi) mechanisms of EV uptake by cancer cells. Intriguingly, EV-mediated intercellular transfer of mutant and oncogenic molecules between subpopulations of cancer cells, their indolent counterparts and stroma may exert profound biological effects that often resemble (but are not tantamount to) oncogenic transformation, including changes in cell growth, clonogenicity and angiogenic phenotype, or cause cell stress and death. However, several biological barriers likely curtail a permanent horizontal transformation of normal cells through EV-mediated mechanisms. The ongoing analysis and targeting of EV-mediated intercellular communication pathways can be viewed as a new therapeutic paradigm in cancer, while the analysis of oncogenic cargo contained in EVs released from cancer cells into biofluids is being developed for clinical use as a biomarker and companion diagnostics. Indeed, studies are underway to further explore the multiple links between molecular causality in cancer and various aspects of cellular vesiculation.

Plasma D-dimer levels and ischaemic lesions in multiple vascular regions can predict occult cancer in patients with cryptogenic stroke

BACKGROUND AND PURPOSE

Cancer patients with cryptogenic stroke often have high plasma D-dimer levels and lesions in multiple vascular regions. Hence, if patients with cryptogenic stroke display such characteristics, occult cancer could be predicted. This study aimed to investigate the clinical characteristics of cryptogenic stroke as the first manifestation of occult cancer and to determine whether plasma D-dimer levels and lesions in multiple vascular regions can predict occult cancer in patients with cryptogenic stroke.

METHODS

Between January 2006 and October 2015, data on 1225 patients with acute ischaemic stroke were extracted from the stroke database of Osaka University Hospital. Among them, 184 patients were classified as having cryptogenic stroke, and 120 patients without a diagnosis of cancer at stroke onset were identified. Clinical variables were analyzed between cryptogenic stroke patients with and without occult cancer.

RESULTS

Among 120 cryptogenic stroke patients without a diagnosis of cancer, 12 patients had occult cancer. The body mass index, hemoglobin levels and albumin levels were lower; plasma D-dimer and high-sensitivity C-reactive protein levels were higher; and lesions in multiple vascular regions were more common in patients with than in those without occult cancer. Multiple logistic regression analysis revealed that plasma D-dimer levels (odds ratio, 3.48; 95% confidence interval, 1.68-8.33; P = 0.002) and lesions in multiple vascular regions (odds ratio, 7.40; 95% confidence interval, 1.70-39.45; P = 0.01) independently predicted occult cancer.

CONCLUSIONS

High plasma D-dimer levels and lesions in multiple vascular regions can be used to predict occult cancer in patients with cryptogenic stroke.

Trends in Hospitalization and Mortality of Venous Thromboembolism in Hospitalized Patients With Colon Cancer and Their Outcomes: US Perspective

INTRODUCTION

Venous thromboembolism (VTE) is a major cause of morbidity and mortality in hospitalized patients with colon cancer. We assessed nationwide population-based trends in rates of hospitalization and mortality from VTE among patients with colon cancer to determine its impact.

METHODS

We queried the Nationwide Inpatient Sample (NIS) database entries from 2003 to 2011 to identify patients with colon cancer. Bivariate group comparisons between hospitalized patients with colon cancer with VTE to those without VTE were made. Multivariate logistic regression analysis was used to obtain adjusted odds ratios. The Cochrane-Armitage test for linear trend was used to assess occurrences of VTE and mortality rates among patients with colon cancer.

RESULTS

The total number patients with colon cancer was 1,502,743, of which 41,394 (2.75%) had VTE. The median age of the study population was 69 years; 51.5% were women. After adjusting for potential confounders, compared with those without VTE, patients with colon cancer with VTE had significantly higher inpatient mortality (6.26% vs. 5.52%, OR 1.15, P < .001) and greater disability at discharge (OR 1.38, P < .001), but were not associated with longer length of stay (LOS) or cost of hospitalization. From 2003 to 2011, despite an increase in hospitalization rate with VTE in patients with colon cancer, their mortality steadily declined.

CONCLUSION

VTE in hospitalized patients with colon cancer is associated with a significantly higher inpatient mortality and greater disability, but not with longer LOS or cost of hospitalization. Furthermore, even though there has been a trend toward more frequent hospitalizations in this patient population, their mortality continues to decline.

Anticoagulation in combination with antiangiogenesis and chemotherapy for cancer patients: evidence and hypothesis

Hypercoagulable state and disorganized angiogenesis are two conspicuous characteristics during tumor progression. There are a considerable number of clinical trials focusing on the effects of anticoagulant and antiangiogenic drugs on the survival of cancer patients. Favorable outcomes have been observed. Excessive blood coagulation not only causes cancer-associated thrombosis, which is a common complication and is the second leading cause of death in patients, but also decreases intratumoral perfusion rates and drug delivery by reducing the effective cross-sectional area of blood vessels. Meanwhile, structural and functional abnormalities of the tumor microvasculature also compromise convective drug transport and create a hypoxic and acidic microenvironment. Vascular normalization strategy can temporarily recover the abnormal state of tumor vasculature by improving blood density, dilation, and leakiness, resulting in enhanced penetration of chemotherapies and oxygen within a short time window. In this article, we first review the evidence to support the opinion that anticoagulant and antiangiogenic therapy can improve cancer survival through several underlying mechanisms. Next, we speculate on the feasibility and value of the combined strategy and discuss whether such a combination has a synergistic antineoplastic effect in cancer patients by way of increasing blood vessel perfusion and drug distribution.

Prostaglandin E synthase is upregulated by Gas6 during cancer-induced venous thrombosis

Venous thromboembolism is a common complication of cancer. Based on recent evidence that (1) growth arrest-specific 6 (Gas6) regulates the expression of tissue factor during venous thrombosis, and (2) cancer promotes a procoagulant milieu, we hypothesize that Gas6 may be involved in cancer-induced coagulopathy. Venous thrombi were induced in both wild-type (WT) and Gas6-deficient ((-/-)) mice with cancer. WT mice with cancer developed larger thrombi than their healthy counterparts; these larger thrombi induced by cancer were not seen in Gas6(-/-) mice. Whole genome microarray analysis of differential gene expression in WT and Gas6(-/-) endothelial cells exposed to M27 murine lung carcinoma cells reveal that Gas6 increases prostaglandin E synthase (Ptges) expression in endothelial cells. This was confirmed using real-time polymerase chain reaction and immunofluorescence staining. Culture of WT endothelial cells with M27 increases the secretion of prostaglandin E2 (PGE2), the enzymatic product of Ptges, in WT but not in Gas6(-/-) endothelial cells. In WT endothelial cells, Ptges expression was regulated through extracellular signal-regulated kinase 1/2 phosphorylation (ERK1/2). In vitro, PGE2 activates platelets after binding to its receptor, EP3. In vivo, EP3 receptor antagonism reversed the effect of cancer-induced thrombosis in WT mice. These results show that Gas6, through upregulation of PGE2, contributes to cancer-induced venous thrombosis.

The humanistic and economic burden of venous thromboembolism in cancer patients: a systematic review

The objective of this study was to present evidence on the epidemiology, health outcomes and economic burden of cancer-related venous thromboembolism (VTE). Medline, Cochrane Central Register of Controlled Trials, Econlit, Science Direct, JSTOR, Oxford Journals and Cambridge Journals were searched. The systematic literature search was limited to manuscripts published from January 2000 to December 2012. On the basis of the literature, cancer patients experience between two-fold and 20-fold higher risk of developing VTE than noncancer patients. They are more likely to experience a VTE event during the first 3-6 months after cancer diagnosis. In addition, an increased risk of VTE in patients with distant metastases and certain types of cancer (i.e. pancreatic or lung) was revealed. VTE was found to be a leading cause of mortality in cancer patients. The annual average total cost for cancer patients with VTE was found to be almost 50% higher than that of cancer patients without VTE. Inpatient care costs accounted for more than 60% of total cost. The existing evidence assessed in the present review demonstrated the significant health and economic consequences of cancer-related VTE, which make a strong case for the importance of its proper and efficient prevention and management.

Venous thrombosis and cancer: from mouse models to clinical trials

Cancer patients have a ~4 fold increased risk of venous thromboembolism (VTE) compared with the general population and this is associated with significant morbidity and mortality. This review summarizes our current knowledge of VTE and cancer, from mouse models to clinical studies. Notably, the risk of VTE varies depending on the type and stage of cancer. For instance, pancreatic and brain cancer patients have a higher risk of VTE than breast and prostate cancer patients. Moreover, patients with metastatic disease have a higher risk than those with localized tumors. Tumor-derived procoagulant factors and growth factors may directly and indirectly enhance VTE. For example, increased levels of circulating tumor-derived, tissue factor-positive microvesicles may trigger VTE. In a mouse model of ovarian cancer, tumor-derived IL-6 and hepatic thrombopoietin have been linked to increased platelet production and thrombosis. In addition, mouse models of mammary and lung cancer showed that tumor-derived granulocyte colony-stimulating factor causes neutrophilia and activation of neutrophils. Activated neutrophils can release neutrophil extracellular traps (NETs) that enhance thrombosis. Cell-free DNA in the blood derived from cancer cells, NETs and treatment with cytotoxic drugs can activate the clotting cascade. These studies suggest that there are multiple mechanisms for VTE in patients with different types of cancer. Preventing and treating VTE in cancer patients is challenging; the current recommendations are to use low-molecular-weight heparin. Understanding the underlying mechanisms may allow the development of new therapies to safely prevent VTE in cancer patients.

High-Dose Vitamin C Injection to Cancer Patients May Promote Thrombosis Through Procoagulant Activation of Erythrocytes

Potential risk of high-dose vitamin C consumption is often ignored. Recently, gram-dose vitamin C is being intravenously injected for the treatment of cancer, which can expose circulating blood cells to extremely high concentrations of vitamin C. As well as platelets, red blood cells (RBCs) can actively participate in thrombosis through procoagulant activation. Here, we examined the procoagulant and prothrombotic risks associated with the intravenous injection of gram-dose vitamin C. Vitamin C (0.5-5 mM) increased procoagulant activity of freshly isolated human RBCs via the externalization of phosphatidylserine (PS) to outer cellular membrane and the formation of PS-bearing microvesicles. PS exposure was induced by the dysregulation of key enzymes for the maintenance of membrane phospholipid asymmetry, which was from vitamin C-induced oxidative stress, and resultant disruption of calcium and thiol homeostasis. Indeed, the intravenous injection of vitamin C (0.5-1.0 g/kg) in rats in vivo significantly increased thrombosis. Notably, the prothrombotic effects of vitamin C were more prominent in RBCs isolated from cancer patients, who are at increased risks of thrombotic events. Vitamin C-induced procoagulant and prothrombotic activation of RBCs, and increased thrombosis in vivo. RBCs from cancer patients exhibited increased sensitivity to the prothrombotic effects of vitamin C, reflecting that intravenous gram-dose vitamin C therapy needs to be carefully revisited.

B blood group: A strong risk factor for venous thromboembolism recurrence

BACKGROUND

Non-O blood group patients are at higher risk of first episode of venous thromboembolism (VTE). However, only little is known about the risk of recurrence according to the blood group. In this study, we aimed to determine the impact of ABO blood group on VTE recurrence.

METHODS

We prospectively recruited 106 consecutive patients with a first documented episode of pulmonary embolism (PE). Patients were followed at least 12months after anticoagulation discontinuation. The main endpoint was recurrence of symptomatic VTE.

RESULTS

Data from 100 patients were analyzed. Median follow-up was 28months [24-34.8]. PE was unprovoked in 48 patients. Mean anticoagulation duration was 5.3±2.2months. The rate of VTE recurrence was 12.7 per 100 patient-years (30 recurrences). B blood group patients had a 2.7-fold increased risk of VTE recurrence (95%CI 1.1-6.2, p=0.03). On multivariate analysis, B blood group was the strongest independent predictor of VTE recurrence (Hazard Ratio (HR) 2.6, 95%CI 1.1-6.1, p=0.04). In contrast, A and AB blood groups were not associated with VTE recurrence. VTE recurrences were less frequent in O blood group compared to non-O patients (HR 0.5, 95%CI 0.2-1.1, p=0.09). O blood group women had a 5-fold decreased risk of VTE recurrence (HR 0.2, 95%CI 0.1-0.8, p=0.01).

CONCLUSIONS

Non-O blood groups, beyond being involved in the occurrence of a first VTE event, also contribute to VTE recurrence. B blood group is strongly associated with VTE recurrence, thus high-risk B blood group patients could benefit from long-term anticoagulation therapy after a first VTE event.

Venous thrombosis in pancreaticobiliary tract cancer: outcome and prognostic factors

BACKGROUND

The differences in outcome among cancer patients with incidental vs. symptomatic venous thromboembolism (VTE) are unknown. In this study, patients with extrahepatic pancreaticobiliary tract cancer (PBC) were selected for a prospective cohort study between February 2008 and February 2011.

METHODS

At the time of cancer diagnosis, all patients were examined for deep vein thrombosis with bilateral compression ultrasonography (biCUS). Computed tomography pulmonary angiography was also performed to diagnose pulmonary embolisms. After inclusion, the patients were followed up with clinical examinations, blood collections, and biCUS.

RESULTS

A total of 121 PBC patients were enrolled. At the time of cancer diagnosis, 15 patients had experienced a VTE (12.4%, 95% confidence interval [CI] 7.1-19.6), including six symptomatic and nine incidental cases. A total of 25 first-time VTE events were identified (20.7%; 95% CI 13.8-29.0). Patients with a VTE had reduced survival, with a median overall survival (OS) of 4.4 months (95% CI 2.2-11.5). The median OS of the patients with incidental VTE was 3.0 months (95% CI 0.1-15.0), which was not different from the median OS of the patients with symptomatic VTE (5.0 months; 95% CI 2.1-14.5). The median OS was 11.9 months (95% CI 8.1-14.7) in the PBC patients with no VTEs.

CONCLUSION

The occurrence of a VTE event in a PBC patient within the first months of the disease is associated with significantly increased mortality.

Pharmacogenomics and targeted therapy of cancer: Focusing on non-small cell lung cancer

Recent studies have been established high degree of genetic diversity in solid organ tumors among individuals and even between individual tumor cells. This intratumor and intertumor genetic diversity results in a heterogeneous tumor with unique characteristics which potentially allows effective drug therapy. The goal of pharmacogenomics is to elucidate the genetic network(s) that underlie drug efficacy and drug resistance. Advances in targeted and personalized therapy play an increasingly important role in many common cancers, notably lung cancer, due to the high incidence, prevalence, mortality and the greater tendency towards drug resistance seen in these patients. Non-small cell lung cancer (NSCLC) is characterized by mutations in the epidermal growth factor receptor (EGFR) and or downstream kinase pathways. This has led to the development of highly selective monoclonal antibodies and EGFR tyrosine kinase inhibitors (EGFR-TKIs) to prevent cancer initiation, proliferation, differentiation, angiogenesis, survival, and invasion. However, resistance to many of these new treatments is induced and further pharmacogenomic analysis has revealed mutations associated with increased or reduced drug efficacy. Combinations of kinase inhibitors or potentially the targeting of cancer stem cells may further increase the success of pharmacogenomics in treating patients with lung cancer.

Oncogenes and the coagulation system--forces that modulate dormant and aggressive states in cancer

Cancers arise and progress genetically amidst profound perturbations of the microenvironmental and systemic homeostasis. This includes the coagulation system, which is a part of the vascular milieu (niche) that remains under the control of molecular events occurring within the cancer cell genome. Thus, activation of several prototypic oncogenic pathways, such as RAS, EGFR, HER2, MET, SHH and loss of tumor suppressors (PTEN, TP53) alter the expression, activity and vesicular release of coagulation effectors, as exemplified by tissue factor (TF). The cancer-specific determinants of coagulopathy are also illustrated by the emerging link between the expression profiles of coagulation-related genes (coagulome) in glioblastoma multiforme (GBM), medulloblastoma (MB) and possibly other cancers and molecular subtypes of these respective tumors. The state of the coagulome is consequential for growth, metastasis and angiogenesis of established tumors, but could potentially also affect dormant cancer cells. For example, TF expression may trigger awakening of dormant glioma cells in mice in a manner involving recruitment of vascular and inflammatory cells, and resulting in lasting changes in the cancer cell genome and epigenome. Thus, coagulation system effectors could act as both targets and (indirect) inducers of genetic tumor progression, and a better understanding of this link may hold new diagnostic and therapeutic opportunities.

Treatment-related frequency of venous thrombosis in lower esophageal, gastro-esophageal and gastric cancer--a clinical prospective study of outcome and prognostic factors

INTRODUCTION

Prospective studies of chemotherapy-associated VTE in cancer patients undergoing neoadjuvant chemotherapy in combination with curative intended surgery have not been reported for upper gastrointestinal cancer. In this clinical prospective study, we sought to estimate the incidence of VTE in esophagogastric cancer (OEC) patients scheduled for a specific perioperative chemotherapy regime: oxaliplatin, capecitabine, and epirubicin, (EXE) and curative intended surgery.

MATERIAL AND METHODS

A total of 129 consecutive OEC patients were examined using state-of-the-art bilateral compression ultrasound (biCUS) for deep vein thrombosis (DVT) before undergoing preoperative chemotherapy, surgery, and postoperative chemotherapy. In addition 79 were also consecutively scanned at baseline for pulmonary embolism (PE) using state-of-the-art computer tomography pulmonary angiography (CTPA).

RESULTS

There were 21 VTE cases throughout the course of treatment (16%, 95% confidence interval [95% CI]: 10 - 24%) among the patients examined using both biCUS and CTPA. Fourteen of 21 VTE was incidental (68%, 95% CI: 43 -85) and 7 VTE events was symptomatic (33%, 15 - 57). The median overall survival was 18months (95% CI: 13 - 24) in patients without any VTE and 14months (95% CI: 7 -30, P = 0.820) in patients with VTE. The cancer stage (adjusted odds ratio [OR]: 5.2, 95% CI: 1 - 21, p=0.002) and gastric cancer (OR 6.4, 95% CI: 2 - 21, P = 0.002) was a significant predictor of VTE.

CONCLUSION

The incidence of VTE in patients undergoing EXE neoadjuvant chemotherapy was high, particularly among patients with initial stage III and IV cancers. In addition, a substantial number of chemotherapy-related VTE cases were asymptomatic.

Anti-platelet agents augment cisplatin nanoparticle cytotoxicity by enhancing tumor vasculature permeability and drug delivery

Tumor vasculature is critically dependent on platelet mediated hemostasis and disruption of the same can augment delivery of nano-formulation based chemotherapeutic agents which depend on enhanced permeability and retention for tumor penetration. Here, we evaluated the role of Clopidogrel, a well-known inhibitor of platelet aggregation, in potentiating the tumor cytotoxicity of cisplatin nano-formulation in a murine breast cancer model. In vivo studies in murine syngeneic 4T1 breast cancer model showed a significant greater penetration of macromolecular fluorescent nanoparticles after clopidogrel pretreatment. Compared to self-assembling cisplatin nanoparticles (SACNs), combination therapy with clopidogrel and SACN was associated with a 4 fold greater delivery of cisplatin to tumor tissue and a greater reduction in tumor growth as well as higher survival rate. Clopidogrel enhances therapeutic efficiency of novel cisplatin based nano-formulations agents by increasing tumor drug delivery and can be used as a potential targeting agent for novel nano-formulation based chemotherapeutics.

The Duality of Fgl2 - Secreted Immune Checkpoint Regulator Versus Membrane-Associated Procoagulant: Therapeutic Potential and Implications

Fibrinogen-like protein 2 (Fgl2), a member of the fibrinogen family, can be expressed as a membrane-associated protein with coagulation activity or in a secreted form possessing unique immune suppressive functions. The biological importance of Fgl2 is evident within viral-induced fibrin depositing inflammatory diseases and malignancies and provides a compelling rationale for Fgl2 expression to not only be considered as a disease biomarker but also as a therapeutic target. This article will provide a comprehensive review of the currently known biological properties of Fgl2 and clarifies future scientific directives.

Multiple hypercoagulability disorders at presentation of non-small-cell lung cancer

Hypercoagulability disorders are commonly encountered in clinical situations in patients with a variety of cancers. However, several hypercoagulability disorders presenting as first symptoms or signs in cancer patients have rarely been reported. We herein described a case of a woman with adenocarcinoma of the lung presenting with deep vein thrombosis, nonbacterial thrombotic endocarditis, recurrent cerebral embolic infarction, and heart failure.

Platelet effects on ovarian cancer

Growing understanding of the role of thrombocytosis, high platelet turnover, and the presence of activated platelets in the circulation in cancer progression and metastasis has brought megakaryocytes into focus. Platelet biology is essential to hemostasis, vascular integrity, angiogenesis, inflammation, innate immunity, wound healing, and cancer biology. However, before megakaryocyte/platelet-directed therapies can be considered for clinical use, understanding of the mechanism and biology of paraneoplastic thrombocytosis in malignancy is required. Here, we provide an overview of the clinical implications, biological significance, and mechanisms of paraneoplastic thrombocytosis in the context of ovarian cancer.

Platelets and cancer: a casual or causal relationship: revisited

Human platelets arise as subcellular fragments of megakaryocytes in bone marrow. The physiologic demand, presence of disease such as cancer, or drug effects can regulate the production circulating platelets. Platelet biology is essential to hemostasis, vascular integrity, angiogenesis, inflammation, innate immunity, wound healing, and cancer biology. The most critical biological platelet response is serving as "First Responders" during the wounding process. The exposure of extracellular matrix proteins and intracellular components occurs after wounding. Numerous platelet receptors recognize matrix proteins that trigger platelet activation, adhesion, aggregation, and stabilization. Once activated, platelets change shape and degranulate to release growth factors and bioactive lipids into the blood stream. This cyclic process recruits and aggregates platelets along with thrombogenesis. This process facilitates wound closure or can recognize circulating pathologic bodies. Cancer cell entry into the blood stream triggers platelet-mediated recognition and is amplified by cell surface receptors, cellular products, extracellular factors, and immune cells. In some cases, these interactions suppress immune recognition and elimination of cancer cells or promote arrest at the endothelium, or entrapment in the microvasculature, and survival. This supports survival and spread of cancer cells and the establishment of secondary lesions to serve as important targets for prevention and therapy.

Venous thromboembolism during primary treatment of ovarian clear cell carcinoma is associated with decreased survival

OBJECTIVES

To determine the impact of venous thromboembolism (VTE) during primary treatment of ovarian clear cell carcinoma (OCCC) on survival.

METHODS

After Institutional Review Board approval, 74 cases of OCCC were retrieved from our pathology files. Clinical and pathological data were obtained by medical record and pathology review. Standard statistical analyses were performed.

RESULTS

Among 74 patients with OCCC, VTE was diagnosed in 11 (15%) during primary treatment and 7 (9%) at time of cancer recurrence. 56 (76%) patients never developed VTE. Patients with VTE during OCCC primary treatment had shorter progression-free survival (PFS) and overall survival (OS) than OCCC patients without VTE (median PFS 11 vs. 76 months, p=0.01, median OS 19 vs. 90 months, p=0.001). Patients with VTE during OCCC primary treatment had a 3.9-fold increase in risk of recurrence (p=0.007) and a 6.3-fold increase in risk of death (p<0.001). After controlling for cancer stage, VTE during OCCC primary treatment remained an independent prognostic factor for death (HR=3.6, p=0.005). No patient died of VTE.

CONCLUSIONS

VTE during OCCC primary treatment is associated with a significantly higher risk of cancer recurrence and death. This increased risk is not attributable to VTE-related mortality and raises the possibility that a paracrine circuit involving thrombosis might contribute to a more aggressive tumor biology.

Oral anticoagulants in the management of venous thromboembolism

Despite advances in diagnosis, prevention, and management, venous thromboembolism (VTE) remains a common cause of morbidity and mortality. For decades, antithrombotic therapy for prevention and treatment of VTE was limited to parenteral agents related to heparin and oral vitamin K antagonists (VKAs). Both classes of anticoagulants are effective, but have limitations, including considerable variability in dose-response, narrow therapeutic margins between the risks of thrombosis and bleeding, and the need to monitor anticoagulation intensity. Over the past decade, the introduction of new oral anticoagulants that specifically inhibit coagulation factors IIa (thrombin) or Xa has changed practice in a variety of clinical situations, including VTE prophylaxis and treatment. In this Review, we outline the use of the novel oral anticoagulants apixaban, dabigatran, edoxaban, and rivaroxaban in the prevention and treatment of VTE, and discuss practical considerations for choosing the appropriate drug for each patient. Although the introduction of novel anticoagulant drugs is promising, selecting the optimum strategy for an individual patient requires an understanding of the specific circumstances associated with thrombus formation and the pharmacological properties of each agent.

Cancer-related coagulopathy (Trousseau's syndrome): review of the literature and experience of a single center of internal medicine

Venous thromboembolism (VTE) occurs roughly in one out of five cancer patients and is the second cause of death in this population. When all cancer patients are considered together, a sevenfold increased risk for VTE has been calculated. Over the last 20 years, a number of risk factors have been recognized. These have been used in several risk assessment models aimed at identifying high-risk patients who are therefore candidates for thromboprophylaxis. An easily applicable and reliable risk score is based on the cancer site, hemoglobin levels, pre-chemotherapy platelet and leukocyte counts as well as body mass index. The additional measurement of two biomarkers, namely D-dimer and soluble P-selectin, may improve estimates of the cumulative VTE probability. A variable incidence of VTE has been determined in patients with specific types of malignancy, with the highest odds in those with pancreatic cancer followed by head and neck tumors. In terms of histotype, the risk of VTE is significantly higher in patients with adenocarcinoma than in those with squamous cell carcinoma and in patients with high-grade versus low-grade tumors. Cancer therapy may also be responsible for VTE; specifically, the presence of an indwelling central venous catheter, immunomodulatory drugs such as thalidomide and lenalidomide, monoclonal antibodies, such as bevacizumab, erythropoiesis-stimulating agents and hormonal therapy with tamoxifen place patients at higher risk. The pathogenesis of cancer-related VTE is poorly understood but is likely to be multifactorial. "Virchow's triad," comprising stasis consequent to a decreased blood flow rate, an enhanced blood clotting tendency such as accompanies inflammation and growth factor expression, and structural modifications in blood vessel walls, is thought to play a central role in the induction of VTE. The prophylaxis and treatment of VTE are based on well-established drugs such as vitamin K antagonists and unfractionated and low-molecular-weight heparins as well as on an expanding group of new oral anticoagulants, including fondaparinux, rivaroxaban, apixaban and dabigatran. Furthermore, aspirin has been shown to prevent arterial thrombosis and to reduce the rate of major vascular events. Guidelines for the general management of VTE in cancer patients and in those with an indwelling central venous catheter have been recently developed with the aim of selecting the most rational therapeutic approach for each clinical situation. The main features of VTE based on our own observations of 92 cancer patients and 159 patients with non-neoplastic disease are briefly described herein.

Stroke and cancer: the importance of cancer-associated hypercoagulation as a possible stroke etiology

BACKGROUND AND PURPOSE

The importance of cancer-associated hypercoagulability as a possible stroke etiology in patients with cancer has received relatively little attention to date. A recent study has suggested that cancer-associated hypercoagulation may be of special importance in the absence of conventional stroke mechanisms.

METHODS

We identified patients with ischemic stroke sequentially admitted to our stroke center with the additional diagnosis of active and malignant cancer from 2002 to 2011. By using our prospectively collected stroke, MRI, and laboratory data banks, the etiology and risk factors of stroke, types of cancer, deep vein thrombosis/pulmonary embolism, d-dimer levels, and diffusion-weighted imaging lesion patterns were compared to an age- and sex-matched control group. Patients with cancer with a conventional stroke etiology and patients with an unidentified and/or cancer-associated stroke etiology were analyzed separately.

RESULTS

One hundred forty patients with cancer and 140 control subjects were included. Unidentified stroke (P<0.001) and infarction in multiple vascular territories (P<0.001) were significantly more frequent and d-dimer levels significantly higher (P<0.05) in patients with cancer. Vice versa, risk factors such as hypertension (P<0.05) and hyperlipidemia (P<0.01) were more prevalent in control subjects. Deep vein thrombosis and pulmonary embolism were more frequent (P<0.01) and d-dimer levels higher (P<0.01) in the patients with unidentified and/or cancer-associated stroke etiology compared to the patients with cancer with a conventional stroke etiology. Lung and pancreatic cancer were significantly overrepresented and d-dimer levels higher in these patients compared with other patients with cancer (P<0.01).

CONCLUSIONS

Our data confirm the concept of cancer-associated hypercoagulation as a widely underestimated important stroke risk factor in patients with cancer, especially in those with severely elevated d-dimer levels and in the absence of conventional risk factors.