THROMBOCYTOSIS ASSOCIATED WITH MALIGNANT DISEASE

Cancer progression and tumor hypercoagulability: a platelet perspective

Venous thromboembolism, which is common in cancer patients and accompanies or even precedes malignant tumors, is known as cancer-related thrombosis and is an important cause of cancer- associated death. At present, the exact etiology of the elevated incidence of venous thrombosis in cancer patients remains elusive. Platelets play a crucial role in blood coagulation, which is intimately linked to the development of arterial thrombosis. Additionally, platelets contribute to tumor progression and facilitate immune evasion by tumors. Tumor cells can interact with the coagulation system through various mechanisms, such as producing hemostatic proteins, activating platelets, and directly adhering to normal cells. The relationship between platelets and malignant tumors is also significant. In this review article, we will explore these connections.

A circle of life: platelet and megakaryocyte cytoskeleton dynamics in health and disease

Platelets are blood cells derived from megakaryocytes that play a central role in regulating haemostasis and vascular integrity. The microtubule cytoskeleton of megakaryocytes undergoes a critical dynamic reorganization during cycles of endomitosis and platelet biogenesis. Quiescent platelets have a discoid shape maintained by a marginal band composed of microtubule bundles, which undergoes remarkable remodelling during platelet activation, driving shape change and platelet function. Disrupting or enhancing this process can cause platelet dysfunction such as bleeding disorders or thrombosis. However, little is known about the molecular mechanisms underlying the reorganization of the cytoskeleton in the platelet lineage. Recent studies indicate that the emergence of a unique platelet tubulin code and specific pathogenic tubulin mutations cause platelet defects and bleeding disorders. Frequently, these mutations exhibit dominant negative effects, offering valuable insights into both platelet disease mechanisms and the functioning of tubulins. This review will highlight our current understanding of the role of the microtubule cytoskeleton in the life and death of platelets, along with its relevance to platelet disorders.

The pathogenesis of cancer-associated thrombosis

Patients with cancer have a higher risk of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), compared to the general population. Cancer-associated thrombosis (CAT) is a thrombotic event that occurs as a complication of cancer or cancer therapy. Major factors determining VTE risk in cancer patients include not only treatment history and patient characteristics, but also cancer type and site. Cancer types can be broadly divided into three groups based on VTE risk: high risk (pancreatic, ovarian, brain, stomach, gynecologic, and hematologic), intermediate risk (colon and lung), and low risk (breast and prostate). This implies that the mechanism of VTE differs between cancer types and that specific VTE pathways may exist for different cancer types. This review summarizes the specific pathways that contribute to VTE in cancer patients, with a particular focus on leukocytosis, neutrophil extracellular traps (NETs), tissue factor (TF), thrombocytosis, podoplanin (PDPN), plasminogen activator inhibitor-1 (PAI-1), the intrinsic coagulation pathway, and von Willebrand factor (VWF).

Paradigm Shift: A Comprehensive Review of Ovarian Cancer Management in an Era of Advancements

Ovarian cancer (OC) is the female genital malignancy with the highest lethality. Patients present a poor prognosis mainly due to the late clinical presentation allied with the common acquisition of chemoresistance and a high rate of tumour recurrence. Effective screening, accurate diagnosis, and personalised multidisciplinary treatments are crucial for improving patients' survival and quality of life. This comprehensive narrative review aims to describe the current knowledge on the aetiology, prevention, diagnosis, and treatment of OC, highlighting the latest significant advancements and future directions. Traditionally, OC treatment involves the combination of cytoreductive surgery and platinum-based chemotherapy. Although more therapeutical approaches have been developed, the lack of established predictive biomarkers to guide disease management has led to only marginal improvements in progression-free survival (PFS) while patients face an increasing level of toxicity. Fortunately, because of a better overall understanding of ovarian tumourigenesis and advancements in the disease's (epi)genetic and molecular profiling, a paradigm shift has emerged with the identification of new disease biomarkers and the proposal of targeted therapeutic approaches to postpone disease recurrence and decrease side effects, while increasing patients' survival. Despite this progress, several challenges in disease management, including disease heterogeneity and drug resistance, still need to be overcome.

The dynamic role of platelets in cancer progression and their therapeutic implications

Systemic antiplatelet treatment represents a promising option to improve the therapeutic outcomes and therapeutic efficacy of chemotherapy and immunotherapy due to the critical contribution of platelets to tumour progression. However, until recently, targeting platelets as a cancer therapeutic has been hampered by the elevated risk of haemorrhagic and thrombocytopenic (low platelet count) complications owing to the lack of specificity for tumour-associated platelets. Recent work has advanced our understanding of the molecular mechanisms responsible for the contribution of platelets to tumour progression and metastasis. This has led to the identification of the biological changes in platelets in the presence of tumours, the complex interactions between platelets and tumour cells during tumour progression, and the effects of platelets on antitumour therapeutic response. In this Review, we present a detailed picture of the dynamic roles of platelets in tumour development and progression as well as their use in diagnosis, prognosis and monitoring response to therapy. We also provide our view on how to overcome challenges faced by the development of precise antiplatelet strategies for safe and efficient clinical cancer therapy.

Detection of a Prethrombotic State in Patients with Hepatocellular Carcinoma, Using a Clot Waveform Analysis

Background: Although hepatocellular carcinoma (HCC) is frequently associated with thrombosis, it is also associated with liver cirrhosis (LC) which causes hemostatic abnormalities. Therefore, hemostatic abnormalities in patients with HCC were examined using a clot waveform analysis (CWA). Methods: Hemostatic abnormalities in 88 samples from HCC patients, 48 samples from LC patients and 153 samples from patients with chronic liver diseases (CH) were examined using a CWA-activated partial thromboplastin time (APTT) and small amount of tissue factor induced FIX activation (sTF/FIXa) assay. Results: There were no significant differences in the peak time on CWA-APTT among HCC, LC, and CH, and the peak heights of CWA-APTT were significantly higher in HCC and CH than in HVs and LC. The peak heights of the CWA-sTF/FIXa were significantly higher in HCC than in LC. The peak times of the CWA-APTT were significantly longer in stages B, C, and D than in stage A or cases of response. In the receiver operating characteristic (ROC) curve, the fibrin formation height (FFH) of the CWA-APTT and CWA-sTF/FIXa showed the highest diagnostic ability for HCC and LC, respectively. Thrombosis was observed in 13 HCC patients, and arterial thrombosis and portal vein thrombosis were frequently associated with HCC without LC and HCC with LC, respectively. In ROC, the peak time×peak height of the first derivative on the CWA-sTF/FIXa showed the highest diagnostic ability for thrombosis. Conclusion: The CWA-APTT and CWA-sTF/FIXa can increase the evaluability of HCC including the association with LC and thrombotic complications.

Tumor cell-released kynurenine biases MEP differentiation into megakaryocytes in individuals with cancer by activating AhR-RUNX1

Tumor-derived factors are thought to regulate thrombocytosis and erythrocytopenia in individuals with cancer; however, such factors have not yet been identified. Here we show that tumor cell-released kynurenine (Kyn) biases megakaryocytic-erythroid progenitor cell (MEP) differentiation into megakaryocytes in individuals with cancer by activating the aryl hydrocarbon receptor-Runt-related transcription factor 1 (AhR-RUNX1) axis. During tumor growth, large amounts of Kyn from tumor cells are released into the periphery, where they are taken up by MEPs via the transporter SLC7A8. In the cytosol, Kyn binds to and activates AhR, leading to its translocation into the nucleus where AhR transactivates RUNX1, thus regulating MEP differentiation into megakaryocytes. In addition, activated AhR upregulates SLC7A8 in MEPs to induce positive feedback. Importantly, Kyn-AhR-RUNX1-regulated MEP differentiation was demonstrated in both humanized mice and individuals with cancer, providing potential strategies for the prevention of thrombocytosis and erythrocytopenia.

The role of platelets in the regulation of tumor growth and metastasis: the mechanisms and targeted therapy

Platelets are a class of pluripotent cells that, in addition to hemostasis and maintaining vascular endothelial integrity, are also involved in tumor growth and distant metastasis. The tumor microenvironment is a complex and comprehensive system composed of tumor cells and their surrounding immune and inflammatory cells, tumor-related fibroblasts, nearby interstitial tissues, microvessels, and various cytokines and chemokines. As an important member of the tumor microenvironment, platelets can promote tumor invasion and metastasis through various mechanisms. Understanding the role of platelets in tumor metastasis is important for diagnosing the risk of metastasis and prolonging survival. In this study, we more fully elucidate the underlying mechanisms by which platelets promote tumor growth and metastasis by modulating processes, such as immune escape, angiogenesis, tumor cell homing, and tumor cell exudation, and further summarize the effects of platelet-tumor cell interactions in the tumor microenvironment and possible tumor treatment strategies based on platelet studies. Our summary will more comprehensively and clearly demonstrate the role of platelets in tumor metastasis, so as to help clinical judgment of the potential risk of metastasis in cancer patients, with a view to improving the prognosis of patients.

Inhibition of Factor XI: A New Era in the Treatment of Venous Thromboembolism in Cancer Patients?

Direct oral anticoagulants against activated factor X and thrombin were the last milestone in thrombosis treatment. Step by step, they replaced antivitamin K and heparins in most of their therapeutic indications. As effective as the previous anticoagulant, the decreased but persistent risk of bleeding while using direct oral anticoagulants has created space for new therapeutics aiming to provide the same efficacy with better safety. On this basis, drug targeting factor XI emerged as an option. In particular, cancer patients might be one of the populations that will most benefit from this technical advance. In this review, after a brief presentation of the different factor IX inhibitors, we explore the potential benefit of this new treatment for cancer patients.

Emerging Role of Tumor-Educated Platelets as a New Liquid Biopsy Tool for Colorectal Cancer

Colorectal cancer (CRC) is a major cause of cancer-associated death universally. Currently, the diagnosis, prognosis, and treatment monitoring of CRC mostly depends on endoscopy integrated with tissue biopsy. Recently, liquid biopsy has gained more and more attention in the area of molecular detection and monitoring of tumors due to ease of sampling, and its safe, non-invasive, and dynamic nature. Platelets, despite their role in hemostasis and thrombosis, are known to have an active, bifacial relationship with cancers. Platelets are the second most common type of cell in the blood and are one of the wealthy liquid biopsy biosources. These cells have the potential to absorb nucleic acids and proteins and modify their transcriptome with regard to external signals, which are termed tumor-educated platelets (TEPs). Liquid biopsies depend on TEPs' biomarkers which can be used to screen and also detect cancer in terms of prognosis, personalized treatment, monitoring, and prediction of recurrence. The value of TEPs as an origin of tumor biomarkers is relatively new, but platelets are commonly isolated using formidable and rapid techniques in clinical practice. Numerous preclinical researches have emphasized the potential of platelets as a new liquid biopsy biosource for detecting several types of tumors. This review discusses the potential use of platelets as a liquid biopsy for CRC.

Venous Thromboembolism and Primary Thromboprophylaxis in Perioperative Pancreatic Cancer Care

Recent studies have shown that patients with pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant chemo(radio)therapy followed by surgery have an improved outcome compared to patients treated with upfront surgery. Hence, patients with PDAC are more and more frequently treated with chemotherapy in the neoadjuvant setting. PDAC patients are at a high risk of developing venous thromboembolism (VTE), which is associated with decreased survival rates. As patients with PDAC were historically offered immediate surgical resection, data on VTE incidence and associated preoperative risk factors are scarce. Current guidelines recommend primary prophylactic anticoagulation in selected groups of patients with advanced PDAC. However, recommendations for patients with (borderline) resectable PDAC treated with chemotherapy in the neoadjuvant setting are lacking. Nevertheless, the prevention of complications is crucial to maintain the best possible condition for surgery. This narrative review summarizes current literature on VTE incidence, associated risk factors, risk assessment tools, and primary thromboprophylaxis in PDAC patients treated with neoadjuvant chemo(radio)therapy.

The overall process of metastasis: From initiation to a new tumor

Metastasis-a process that involves the migration of cells from the primary site to distant organs-is the leading cause of cancer-associated death. Improved technology and in-depth research on tumors have furthered our understanding of the various mechanisms involved in tumor metastasis. Metastasis is initiated by cancer cells of a specific phenotype, which migrate with the assistance of extracellular components and metastatic traits conferred via epigenetic regulation while modifying their behavior in response to the complex and dynamic human internal environment. In this review, we have summarized the general steps involved in tumor metastasis and their characteristics, incorporating recent studies and topical issues, including epithelial-mesenchymal transition, cancer stem cells, neutrophil extracellular traps, pre-metastatic niche, extracellular vesicles, and dormancy. Several feasible treatment directions have also been summarized. In addition, the correlation between cancer metastasis and lifestyle factors, such as obesity and circadian rhythm, has been illustrated.

Cancer-associated venous thromboembolism

Cancer-associated thrombosis (including venous thromboembolism (VTE) and arterial events) is highly consequential for patients with cancer and is associated with worsened survival. Despite substantial improvements in cancer treatment, the risk of VTE has increased in recent years; VTE rates additionally depend on the type of cancer (with pancreas, stomach and primary brain tumours having the highest risk) as well as on individual patient's and cancer treatment factors. Multiple cancer-specific mechanisms of VTE have been identified and can be classified as mechanisms in which the tumour expresses proteins that alter host systems, such as levels of platelets and leukocytes, and in which the tumour expresses procoagulant proteins released into the circulation that directly activate the coagulation cascade or platelets, such as tissue factor and podoplanin, respectively. As signs and symptoms of VTE may be non-specific, diagnosis requires clinical assessment, evaluation of pre-test probability, and objective diagnostic testing with ultrasonography or CT. Risk assessment tools have been validated to identify patients at risk of VTE. Primary prevention of VTE (thromboprophylaxis) has long been recommended in the inpatient and post-surgical settings, and is now an option in the outpatient setting for individuals with high-risk cancer. Anticoagulant therapy is the cornerstone of therapy, with low molecular weight heparin or newer options such as direct oral anticoagulants. Personalized treatment incorporating risk of bleeding and patient preferences is essential, especially as a diagnosis of VTE is often considered by patients even more distressing than their cancer diagnosis, and can severely affect the quality of life. Future research should focus on current knowledge gaps including optimizing risk assessment tools, biomarker discovery, next-generation anticoagulant development and implementation science.

Incidence of Cancer Among Adults With Thrombocytosis in Ontario, Canada

IMPORTANCE

Individuals with newly diagnosed cancer often have a high platelet count (thrombocytosis). Whether thrombocytosis is associated with the presence of an undiagnosed cancer remains unknown.

OBJECTIVE

To assess whether a new diagnosis of thrombocytosis is associated with a subsequent risk of cancer among adults.

DESIGN, SETTING, AND PARTICIPANTS

This population-based retrospective cohort study was conducted using linked laboratory data from Ontario, Canada, from January 1, 2007, to December 31, 2017, with follow-up until December 31, 2018. The study cohort included adults aged 40 to 75 years on the date of a routine complete blood count (CBC) test (index test) who had a normal platelet count in the 2 previous years and no history of cancer. Data analysis was performed in December 2020.

EXPOSURES

Exposed individuals were those with a platelet count greater than 450 × 109/L. Matched unexposed control individuals had a platelet count within the reference range (150 × 109/L to 450 × 109/L) reported within 30 days of the exposure.

MAIN OUTCOMES AND MEASURES

Incident cancers within 5 years after diagnosis of thrombocytosis. Absolute and relative risks for cancer associated with thrombocytosis were estimated for all cancers and for cancers at specific sites.

RESULTS

Of the 3 386 716 Ontario residents with a recorded routine CBC test result, 53 339 (1.6%) had thrombocytosis and a prior normal platelet count. Among individuals with thrombocytosis, the median age was 59.7 years (interquartile range, 50.2-67.4 years) and 37 349 (70.0%) were women. Among the 51 624 individuals with thrombocytosis included in the matched analysis, 2844 (5.5%) had received a diagnosis of a solid cancer in the 2-year follow-up period and 3869 (7.5%) had received a diagnosis within 5 years. The relative risk (RR) for developing any solid cancer within 2 years was 2.67 (95% CI, 2.56-2.79). Associations were found between thrombocytosis and cancers of the ovary (RR, 7.11; 95% CI, 5.59-9.03), stomach (RR, 5.53; 95% CI, 4.12-7.41), colon (RR, 5.41; 95% CI, 4.80-6.10), lung (RR, 4.41; 95% CI, 4.02-4.85), kidney (RR, 3.64; 95% CI, 2.94-4.51), and esophagus (RR, 3.64; 95% CI, 2.46-5.40).

CONCLUSIONS AND RELEVANCE

In this cohort study, an increased platelet count was associated with an increased risk of cancer for at least 2 years. The results suggest that individuals with unexplained thrombocytosis should be offered screening for several cancers.

The Provocative Roles of Platelets in Liver Disease and Cancer

Both platelets and the liver play important roles in the processes of coagulation and innate immunity. Platelet responses at the site of an injury are rapid; their immediate activation and structural changes minimize the loss of blood. The majority of coagulation proteins are produced by the liver—a multifunctional organ that also plays a critical role in many processes: removal of toxins and metabolism of fats, proteins, carbohydrates, and drugs. Chronic inflammation, trauma, or other causes of irreversible damage to the liver can dysregulate these pathways leading to organ and systemic abnormalities. In some cases, platelet-to-lymphocyte ratios can also be a predictor of disease outcome. An example is cirrhosis, which increases the risk of bleeding and prothrombotic events followed by activation of platelets. Along with a triggered coagulation cascade, the platelets increase the risk of pro-thrombotic events and contribute to cancer progression and metastasis. This progression and the resulting tissue destruction is physiologically comparable to a persistent, chronic wound. Various cancers, including colorectal cancer, have been associated with increased thrombocytosis, platelet activation, platelet-storage granule release, and thrombosis; anti-platelet agents can reduce cancer risk and progression. However, in cancer patients with pre-existing liver disease who are undergoing chemotherapy, the risk of thrombotic events becomes challenging to manage due to their inherent risk for bleeding. Chemotherapy, also known to induce damage to the liver, further increases the frequency of thrombotic events. Depending on individual patient risks, these factors acting together can disrupt the fragile balance between pro- and anti-coagulant processes, heightening liver thrombogenesis, and possibly providing a niche for circulating tumor cells to adhere to—thus promoting both liver metastasis and cancer-cell survival following treatment (that is, with minimal residual disease in the liver).

Platelets as messengers of early-stage cancer

Platelets have an important role in tumor angiogenesis, growth, and metastasis. The reciprocal interaction between cancer and platelets results in changes of several platelet characteristics. It is becoming clear that analysis of these platelet features could offer a new strategy in the search for biomarkers of cancer. Here, we review the human studies in which platelet characteristics (e.g., count, volume, protein, and mRNA content) are investigated in early-stage cancer. The main focus of this paper is to evaluate which platelet features are suitable for the development of a blood test that could detect cancer in its early stages.

Lessons to learn from tumor-educated platelets

Platelets have long been known to play important roles beyond hemostasis and thrombosis. Now recognized as a bona fide mediator of malignant disease, platelets influence various aspects of cancer progression, most notably tumor cell metastasis. Interestingly, platelets isolated from cancer patients often display distinct RNA and protein profiles, with no clear alterations in hemostatic activity. This phenotypically distinct population, termed tumor-educated platelets, now receive significant attention for their potential use as a readily available liquid biopsy for early cancer detection. Although the mechanisms underpinning platelet education are still being defined, direct uptake and storage of tumor-derived factors, signal-dependent changes in platelet RNA processing, and differential platelet production by tumor-educated megakaryocytes are the most prominent scenarios. This article aims to cover the various modalities of platelet education by tumors, in addition to assessing their diagnostic potential.

Efficacy of Liver Resection for Single Large Hepatocellular Carcinoma in Child-Pugh A Cirrhosis: Analysis of a Nationwide Cancer Registry Database

Background

Therapeutic strategies and good prognostic factors are important for patients with single large hepatocellular carcinoma (HCC). This retrospective study aimed to identify the prognostic factors in patients with single large HCC with good performance status and Child-Pugh A cirrhosis using a large national cancer registry database and to recommend therapeutic strategies.

Methods

Among 12139 HCC patients registered at the Korean Primary Liver Cancer Registry between 2008 and 2015, single large (≥ 5 cm) HCC patients with Eastern Cooperative Oncology Group (ECOG) performance status 0 and Child-Pugh score A were selected.

Results

Overall, 466 patients were analyzed. The 1-,2-,3-, and 5-year survival rates after initial treatment were 84.9%, 71.0%, 60.1%, and 51.6%, respectively, and progression-free survival rates were 43.6%, 33.0%, 29.0%, and 26.8%, respectively. Platelet count < 100 × 10⁹/L (P < 0.001), sodium level < 135 mmol/L (P = 0.002), maximum tumor diameter ≥ 10 cm (P = 0.001), and treatment other than resection (transarterial therapy vs. resection: P < 0.001, others vs. resection: P = 0.002) were significantly associated with poorer overall survival; sodium < 135 mmol/L (P = 0.015), maximum tumor diameter ≥ 10 cm (P < 0.001), and treatment other than resection (transarterial therapy vs. resection: P < 0.001, others vs. resection: P = 0.001) were independently associated with poorer progression-free survival.

Conclusion

Resection as an initial treatment should be considered when possible, even in patients with single large HCC with good performance status and mild cirrhosis. Caution should be exercised in patients with low platelet level (< 100 × 10⁹/L), low serum sodium level (< 135 mmol/L), and maximum tumor diameter ≥ 10 cm.

Prognostic impact of pretreatment thrombocytosis in epithelial ovarian cancer

Aims

This study was aimed at investigating the prognostic impact of pretreatment thrombocytosis in epithelial ovarian cancer (EOC) patients in Lagos, Nigeria.

Methods

This was a retrospective cohort study involving the review of the clinical record of 72 patients with histologically confirmed EOC who were managed at the Lagos University Teaching Hospital, Lagos, Nigeria over a 7-year period from January 2010 to December 2016. Information on the sociodemographic data and platelet counts at diagnosis of EOC were retrieved from the patients' medical records. Descriptive statistics were then computed for all baseline patients' characteristics. Survival analyses were carried out using the Kaplan-Meier estimates. Multivariate analysis of these data was performed with the Cox proportional hazards model.

Results

This study revealed that the prevalence of pretreatment thrombocytosis was 41.7% among the women with EOC. Fifty-three (73.6%) of the women had the advanced-stage disease (FIGO stage III-IV) while 52 (72.2%) had high-grade disease (II-III). The majority (66.7%) of the women had a serous histological type of EOC while 76.4% had documented recurrence. Pretreatment thrombocytosis was significantly associated with the women's parity (P = 0.009), serum carbohydrate antigen 125 levels (P = 0.018), median progression-free survival (PFS) (P < 0.001), 3-year median overall survival (OS) (P < 0.001), type of primary treatment (P = 0.002), extent of cytoreduction (P < 0.001), presence of ascites (P = 0.002), International Federation of Gynecology and Obstetrics (FIGO) stage (P = 0.008), and histological type (P = 0.011). Pretreatment thrombocytosis was negatively associated with PFS (hazard ratio [HR] = 0.25; 95% CI 0.83, 0.75; P = 0.014) and 3-year OS (HR = 0.03; 95% CI 0.03, 0.27; P = 0.002).

Conclusions

The study suggests that pretreatment thrombocytosis may be a useful predictor of survivals in EOC patients.

Thrombocytosis as a Biomarker in Type II, Non-Endometrioid Endometrial Cancer

Thrombocytosis (platelets ≥ 400K) is a common hematologic finding in gynecologic malignancies and associated with worse outcomes. Limited data exist on the prognostic capability of thrombocytosis in women with high-grade endometrial cancer (EC). Our objective was to describe the associations between elevated platelets at diagnosis, clinicopathologic features, and survival outcomes among women with high-grade, non-endometrioid EC. A review of the institutional cancer registry was performed to identify these women treated between 2005 and 2017. Sociodemographic, clinical, and outcomes data were collected. Analyses were performed using chi-square tests, Cox proportional hazards models, and the Kaplan–Meier method. A total of 271 women were included in the analysis. A total of 19.3% of women had thrombocytosis at diagnosis. Thrombocytosis was associated with reduced median overall survival (OS) compared with those not displaying thrombocytosis (29.4 months vs. 60 months, p < 0.01). This finding was most pronounced in uterine serous carcinoma (16.4 months with thrombocytosis vs. 34.4 months without, p < 0.01). While non-White women had shorter median OS for the whole cohort in the setting of thrombocytosis (29.4 months vs. 39.6 months, p < 0.01), among those with uterine serous carcinoma (USC), this finding was reversed, with decreased median OS in White women (22.1 vs. 16.4 months, p = 0.01). Thrombocytosis is concluded to have negative associations with OS and patient race.

Targeting platelets for improved outcome in KRAS-driven lung adenocarcinoma

Elevated platelet count is associated with poor survival in certain solid cancers, including lung cancer. In addition, experimental transplantation of cancer cell lines has uncovered a role for platelets in blood-borne metastasis. These studies, however, do not account for heterogeneity between lung cancer subtypes. Subsequently, the role of platelets in the major subtypes of non-small cell lung cancer (adenocarcinoma (ADC) and squamous cell carcinoma (SqCC)) is not fully understood. We utilised an autochthonous Kras^LSL-G12D/+;p53^flox/flox mouse model of lung ADC together with genetic models of thrombocytopenia to interrogate the role of platelets in lung cancer growth and progression. While thrombocytopenia failed to impact primary tumour growth, in experimental metastatic models however, thrombocytopenic mice displayed significantly extended survival. Utilising a novel thrombocytopenic immunocompromised mouse, the importance of platelets in metastatic dissemination was confirmed with human KRAS-mutant ADC cell lines. Finally, retrospective analysis of a NSCLC patient cohort revealed thrombocytosis was predictive of poor survival in ADC patients with metastatic disease. Interestingly, this association was not apparent in SqCC patients. Overall, these data highlight the possibility of patient stratification using thrombocytosis as a biomarker, and indicates opportunities for potential novel treatment strategies that combine anti-platelet and lung cancer therapies.

Prognostic role of thrombocytosis in recurrent ovarian cancer: a pooled analysis of the AGO Study Group

PURPOSE

Although thrombocytosis in patients with primary ovarian cancer has been widely investigated, there are only very few data about the role of thrombocytosis in recurrent ovarian cancer. The aim of our study was to investigate the impact of pretreatment thrombocytosis prior to chemotherapy on clinical outcome in patients with recurrent platinum eligible ovarian cancer.

METHODS

In our retrospective analysis we included 300 patients who were treated by AGO Study Group Centers within three prospective, randomized phase-III-trials. All patients included had been treatment-free for at least 6 months after platinum-based chemotherapy. We excluded patients who underwent secondary cytoreductive surgery before randomization to the trial. Thrombocytosis was defined as a platelet count of ≥ 400⋅10⁹/L.

RESULTS

Pretreatment thrombocytosis was present in 37 out of 300 (12.3%) patients. Patients with thrombocytosis responded statistically significantly less to chemotherapy (overall response rate 35.3% and 41.6%, P = 0.046). The median progression-free survival (PFS) for patients with thrombocytosis was 6.36 months compared to 9.00 months for patients without thrombocytosis (hazard ratio [HR] = 1.19, 95% confidence interval [CI] = 0.84-1.69, P = 0.336). Median overall survival (OS) of patients with thrombocytosis was 16.33 months compared to 23.92 months of patients with a normal platelet count (HR = 1.46, 95% CI = 1.00-2.14, P = 0.047).

CONCLUSIONS

The present analysis suggests that pretreatment thrombocytosis is associated with unfavorable outcome with regard to response to chemotherapy and overall survival in recurrent ovarian cancer.

Platelets disrupt vasculogenic mimicry by cancer cells

Tumour vasculature supports the growth and progression of solid cancers with both angiogenesis (endothelial cell proliferation) and vasculogenic mimicry (VM, the formation of vascular structures by cancer cells themselves) predictors of poor patient outcomes. Increased circulating platelet counts also predict poor outcome for cancer patients but the influence of platelets on tumour vasculature is incompletely understood. Herein, we show with in vitro assays that platelets did not influence angiogenesis but did actively inhibit VM formation by cancer cell lines. Both platelet sized beads and the releasates from platelets were partially effective at inhibiting VM formation suggesting that direct contact maximises the effect. Platelets also promoted cancer cell invasion in vitro. B16F10 melanomas in Bcl-x^Plt20/Plt20 thrombocytopenic mice showed a higher content of VM than their wildtype counterparts while angiogenesis did not differ. In a xenograft mouse model of breast cancer with low-dose aspirin to inactivate the platelets, the burden of MDA-MB-231-LM2 breast cancer cells was reduced and the gene expression profile of the cancer cells was altered; but no effect on tumour vasculature was observed. Taken together, this study provides new insights into the action of platelets on VM formation and their involvement in cancer progression.

The "Janus Face" of Platelets in Cancer

Besides their vital role in hemostasis and thrombosis, platelets are also recognized to be involved in cancer, where they play an unexpected central role: They actively influence cancer cell behavior, but, on the other hand, platelet physiology and phenotype are impacted by tumor cells. The existence of this platelet-cancer loop is supported by a large number of experimental and human studies reporting an association between alterations in platelet number and functions and cancer, often in a way dependent on patient, cancer type and treatment. Herein, we shall report on an update on platelet-cancer relationships, with a particular emphasis on how platelets might exert either a protective or a deleterious action in all steps of cancer progression. To this end, we will describe the impact of (i) platelet count, (ii) bioactive molecules secreted upon platelet activation, and (iii) microvesicle-derived miRNAs on cancer behavior. Potential explanations of conflicting results are also reported: Both intrinsic (heterogeneity in platelet-derived bioactive molecules with either inhibitory or stimulatory properties; features of cancer cell types, such as aggressiveness and/or tumour stage) and extrinsic (heterogeneous characteristics of cancer patients, study design and sample preparation) factors, together with other confounding elements, contribute to “the Janus face” of platelets in cancer. Given the difficulty to establish the univocal role of platelets in a tumor, a better understanding of their exact contribution is warranted, in order to identify an efficient therapeutic strategy for cancer management, as well as for better prevention, screening and risk assessment protocols.

Platelets promote breast cancer cell MCF-7 metastasis by direct interaction: surface integrin α2β1-contacting-mediated activation of Wnt-β-catenin pathway

Background

Integrin-mediated platelet-tumor cell contacting plays an important role in promoting epithelial-mesenchymal transition (EMT) transformation of tumor cells and cancer metastasis, but whether it occurs in breast cancer cells is not completely clear.

Objective

The purpose of this study was to investigate the role of integrin α2β1 in platelet contacting to human breast cancer cell line MCF-7 and its effect on the EMT and the invasion of MCF-7 cells.

Methods

Human platelets were activated by thrombin, and separated into pellets and releasates before the co-incubation with MCF-7 cells. Cell invasion was evaluated by transwell assay. The surface integrins on pellets and MCF-7 cells were inhibited by antibodies. The effect of integrin α2β1 on Wnt-β-catenin pathway was assessed by integrin α2β1-silencing and Wnt-β-catenin inhibitor XAV. The therapeutic effect of integrin α2β1-silencing was confirmed in the xenograft mouse model.

Results

Pellets promote the invasion and EMT of MCF-7 cells via direct contacting of surface integrin α2β1. The integrin α2β1 contacting activates Wnt-β-catenin pathway and promotes the expression of EMT proteins in MCF-7 cells. The activated Wnt-β-catenin pathway also promotes the autocrine of TGF-β1 in MCF-7 cells. Both Wnt-β-catenin and TGF-β1/pSmad3 pathways promote the expression of EMT proteins. Integrin α2β1-silencing inhibits breast cancer metastasis in vivo.

Conclusions

The direct interaction between platelets and tumor cells exerts its pro-metastatic function via surface integrin α2β1 contacting and Wnt-β-catenin activation. Integrin α2β1-silencing has the potential effect of inhibiting breast cancer metastasis.

New Insights Into the Differentiation of Megakaryocytes From Hematopoietic Progenitors

Megakaryocytes are hematopoietic cells, which are responsible for the production of blood platelets. The traditional view of megakaryopoiesis describes the cellular journey from hematopoietic stem cells, through a hierarchical series of progenitor cells, ultimately to a mature megakaryocyte. Once mature, the megakaryocyte then undergoes a terminal maturation process involving multiple rounds of endomitosis and cytoplasmic restructuring to allow platelet formation. However, recent studies have begun to redefine this hierarchy and shed new light on alternative routes by which hematopoietic stem cells are differentiated into megakaryocytes. In particular, the origin of megakaryocytes, including the existence and hierarchy of megakaryocyte progenitors, has been redefined, as new studies are suggesting that hematopoietic stem cells originate as megakaryocyte-primed and can bypass traditional lineage checkpoints. Overall, it is becoming evident that megakaryopoiesis does not only occur as a stepwise process, but is dynamic and adaptive to biological needs. In this review, we will reexamine the canonical dogmas of megakaryopoiesis and provide an updated framework for interpreting the roles of traditional pathways in the context of new megakaryocyte biology. Visual Overview- An online visual overview is available for this article.

Tumor-educated platelets

Liquid biopsies have been considered the holy grail in achieving effective cancer management, with blood tests offering a minimally invasive, safe, and sensitive alternative or complementary approach for tissue biopsies. Currently, blood-based liquid biopsy measurements focus on the evaluation of biomarker types, including circulating tumor DNA, circulating tumor cells, extracellular vesicles (exosomes and oncosomes), and tumor-educated platelets (TEPs). Despite the potential of individual techniques, each has its own advantages and disadvantages. Here, we provide further insight into TEPs.

Biomarkers of Cancer-Associated Thromboembolism

Venous thromboembolism is known to be associated with an increase in morbidity and mortality in patients with malignancy. Predictive laboratory biomarkers of venous thromboembolism (VTE) have long been sought after to improve outcomes and help guide clinical decision making. Previously studied biomarkers include C reactive protein (CRP), tissue factor expressing microparticles (TF MP), D-dimer, soluble P-selectin (sP-selectin), plasminogen activator inhibitor 1 (PAI-1), factor VIII, platelet count, and leukocyte counts. This chapter will focus on these possible biomarkers for cancer-associated thrombosis (CAT) with particular emphasis on the pathophysiology behind thrombosis formation as well as data from clinical studies in patients with malignancy. The incorporation of the above biomarkers into risk assessment tools to predict CAT will also be reviewed, as will risk factors for recurrent VTE in patients with malignancy. Further studies are ongoing to develop readily available biomarkers that can be incorporated into future risk assessment models with the goal of reducing morbidity and mortality due to cancer-associated thrombosis.

Cancer-Associated Thrombosis in Cirrhotic Patients with Hepatocellular Carcinoma

It is common knowledge that cancer patients are more prone to develop venous thromboembolic complications (VTE). It is therefore not surprising that patients with hepatocellular carcinoma (HCC) present with a significant risk of VTE, with the portal vein being the most frequent site (PVT). However, patients with HCC are peculiar as both cancer and liver cirrhosis are conditions that can perturb the hemostatic balance towards a prothrombotic state. Because HCC-related hypercoagulability is not clarified at all, the aim of the present review is to summarize the currently available knowledge on epidemiology and pathogenesis of non-malignant thrombotic complications in patients with liver cirrhosis and HCC. They are at increased risk to develop both PVT and non-splanchnic VTE, indicating that both local and systemic factors can foster the development of site-specific thrombosis. Recent studies have suggested multiple and often interrelated mechanisms through which HCC can tip the hemostatic balance of liver cirrhosis towards hypercoagulability. Described mechanisms include increased fibrinogen concentration/polymerization, thrombocytosis, and release of tissue factor-expressing extracellular vesicles. Currently, there are no specific guidelines on the use of thromboprophylaxis in this unique population. There is the urgent need of prospective studies assessing which patients have the highest prothrombotic profile and would therefore benefit from early thromboprophylaxis.

The Platelet Lifeline to Cancer: Challenges and Opportunities

Besides their function in limiting blood loss and promoting wound healing, experimental evidence has highlighted platelets as active players in all steps of tumorigenesis including tumor growth, tumor cell extravasation, and metastasis. Additionally, thrombocytosis in cancer patients is associated with adverse patient survival. Due to the secretion of large amounts of microparticles and exosomes, platelets are well positioned to coordinate both local and distant tumor-host crosstalk. Here, we present a review of recent discoveries in the field of platelet biology and the role of platelets in cancer progression as well as challenges in targeting platelets for cancer treatment.

Thrombocytosis in Malignant Pleural Mesothelioma

The prevalence of thrombocytosis (defined as a platelet count above 400,000/mm3 in at least two examinations) and the prevalence of thromboembolism were retrospectively investigated in a series of 41 patients with malignant pleural mesothelioma and in 40 subjects with non small cell lung carcinoma. All the patients were examined at necropsy. The mesothelioma patients showed a higher prevalence of thrombocytosis (56.8% vs 24.2%; p < 0.01). However, the prevalences of thromboembolism were similar in the two groups of patients (36.6% and 32.5% respectively). Among those with mesothelioma the prevalence of thrombocytosis varied widely from one histological type to another (76.9% in mixed type, 57.1% in the epithelial, and 30% in the sarcomatous type), the difference between mixed and sarcomatous being statistically significant (p < 0.01). Moreover, the mesothelioma patients of under 70 years had thrombocytosis more often than those over 70 (80% vs 29.4%; p < 0.01).

Coagulation Disorders in Patients with Tumors of the Uterus

Sixty-eight previously untreated female subjects were studied: 26 patients with cervical carcinoma, 22 with endometrial carcinoma, and 20 with benign uterine diseases. These patients, together with 25 healthy female control subjects, underwent several coagulation tests, including beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) plasma levels. Of all the parameters considered, the variations in beta-TG and PF4 were the most interesting. They were increased in patients with cervical and endometrial carcinoma. The sensitivity of the two tests reached 79% (15/19) for patients with invasive cervical carcinoma and 74% (16/22) for all patients with endometrial carcinoma. Our data demonstrate that among the investigated parameters beta-TG and PF4 are the earliest disorders of the hemostatic system and are more frequently increased in the gynecologic malignancies.

Thrombocytosis in a male patient with acute promyelocytic leukaemia during all-trans retinoic (ATRA) acid treatment

We present a rather uncommon side effect observed in a 20-year-old man with acute promyelocytic leukemia during treatment with ATRA. He developed a high platelet counts reaching up to 1655×10⁹/L on day 29 of ATRA treatment, and started to recover spontaneously on day 33 of treatment, without any change in ATRA, or adding any cytoreduction therapy. No complications associated with thrombocytosis were observed. IL-6 seems to play an important role in the pathogenesis of the thrombocytosis induced by ATRA. However, it is unclear what are the precipitating factors for this rare phenomenon and whether it is caused by certain predisposing factors that might be related to patient's, disease pathogenesis or other unknown factors.

The association of pretreatment thrombocytosis with prognosis and clinicopathological significance in cervical cancer: a systematic review and meta-analysis

Previous studies reported inconsistent findings about the relationship between pretreatment thrombocytosis and survival in patients with cervical cancer. This study aimed to evaluate the prognostic significance of thrombocytosis in cervical cancer. We searched databases to identify relevant articles. Pooled hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Fourteen studies including 3,394 patients were eligible for the meta-analysis. Overall, an elevated platelet count was significantly associated with inferior overall survival (OS, hazard ratio [HR]: 1.66, 95% confidence interval [CI]: 1.42–1.95, P < 0.001) and recurrence-free survival (RFS, HR: 1.67, 95% CI: 1.15–2.42, P = 0.007) but not progression-free survival (PFS, HR: 1.21, 95% CI: 0.89–1.64; P = 0.235). The results were similar for low stage patients treated with surgery alone. Moreover, a pretreatment thrombocytosis status was significantly associated with higher clinical stage (odd ratio [OR]: 2.39, 95% CI: 1.68–3.38, P < 0.001), positive pelvic node status (OR: 1.58, 95% CI: 1.01– 2.45, P = 0.044) and larger tumor size (OR: 2.32, 95% CI: 1.39–3.87, P = 0.001). Pretreatment thrombocytosis is an independent prognosis predictor in cervical cancer patients. It may be used as a readily available biomarker to refine clinical outcome prediction for cervical cancer patients.

Carpe low-dose aspirin: the new anti-cancer face of an old anti-platelet drug

Cancer metastasis is a dynamic process during which cancer cells separate from a primary tumor, migrate through the vessel wall into the bloodstream, and extravasate at distant sites to form secondary colonies. During this process, circulating tumor cells are subjected to shear stress forces from blood flow, and in contact with plasma proteins and blood cells of the immune and hemostatic system, including platelets. Many studies have shown an association between high platelet count and cancer metastasis, suggesting that platelets may play an occult role in tumorigenesis. This mini-review summarizes recent and emerging discoveries of mechanisms by which cancer cells activate platelets and the role of activated platelets in promoting tumor growth and metastasis. Moreover, the review discusses how aspirin has the potential for being clinically used as an adjuvant in cancer therapy.

Routine blood tests and probability of cancer in patients referred with non-specific serious symptoms: a cohort study

BACKGROUND

Danish cancer patients have lower survival rates than patients in many other western countries. Half of the patients present with non-alarm symptoms and thus have a long diagnostic pathway. Consequently, an urgent referral pathway for patients with non-specific serious symptoms was implemented throughout Denmark in 2011-2012. As part of the diagnostic workup, a panel of blood tests are performed for all patients referred by their general practitioner (GP) to the urgent referral pathway. In this study, we analysed the probability of being diagnosed with cancer in GP-referred patients with abnormal blood test results.

METHOD

We performed a cohort study that included all patients aged 18 years or older referred by their GP to Silkeborg Regional Hospital for analysis of a panel of blood tests. All patients were followed for 3 months for a cancer diagnosis in the Danish Cancer Registry. The likelihood ratio and post-test probability of subsequently finding cancer were calculated in relation to abnormal blood test results.

RESULTS

Among the 1499 patients included in the study, 12.2% were subsequently diagnosed with cancer. The probability of cancer increased with the number of abnormal blood tests. Patients with specific combinations of two abnormal blood tests had a 23-62% probability of cancer. Only a few single abnormal blood tests were linked with a high post-test probability of cancer, and most abnormalities were not specific to cancer.

CONCLUSIONS

A number of specific abnormal blood tests and combinations of abnormal blood tests markedly increased the probability of cancer being diagnosed. Still, abnormal blood test results should be interpreted cautiously as most are non-specific to cancer. Thus, results from the blood test panel may strengthen the suspicion of cancer, but blood tests cannot be used as a stand-alone tool to rule out cancer.

Cancer-associated pathways and biomarkers of venous thrombosis

Cancer patients have an increased risk of venous thromboembolism (VTE). In this review, we summarize common and cancer type-specific pathways of VTE in cancer patients. Increased levels of leukocytes, platelets, and tissue factor-positive (TF⁺) microvesicles (MVs) are all potential factors that alone or in combination increase cancer-associated thrombosis. Patients with lung or colorectal cancer often exhibit leukocytosis. Neutrophils could increase VTE in cancer patients by releasing neutrophil extracellular traps whereas monocytes may express TF. Thrombocytosis is often observed in gastrointestinal, lung, breast, and ovarian cancer and this could decrease the threshold required for VTE. Soluble P-selectin has been identified as a biomarker of cancer-associated thrombosis in a general cancer population and may reflect activation of the endothelium. P-selectin expression by the endothelium may enhance VTE by increasing the recruitment of leukocytes. Studies in patients with pancreatic or brain cancer suggest that elevated levels of PAI-1 may contribute to VTE. Although elevated levels of TF⁺ MVs have been observed in patients with different types of cancer, an association between TF⁺ MVs and VTE has been observed only in pancreatic cancer. Podoplanin expression is associated with VTE in patients with brain cancer and may activate platelets. Future studies should measure multiple biomarkers in each cancer type to determine whether combinations of biomarkers can be used as predictors of VTE. A better understanding of the pathways that increase VTE in cancer patients may lead to the development of new therapies to reduce the morbidity and mortality associated with thrombosis.

CD61+ and CAF+ were found to be good prognosis factors for invasive breast cancer patients

BACKGROUND

During the epithelial tumor development process, changes in tumor cell genes are an important driving factor for tumorigenesis. Recently, however, studies have shown that the tumor microenvironment, especially for cancer-associated fibroblasts (CAFs) and the infiltration of platelets into tumors, plays an essential role in the progression of human malignant disease.

METHODS

In this study, we investigated the presence and prognostic role of podoplanin-expressing CAFs (CAF+), the infiltration of platelets into tumors (CD61+) and platelet count before surgery in a large sample of patients with breast cancer. Podoplanin expression and platelet infiltration were evaluated by immunohistochemistry in 164 patients with breast cancer.

RESULTS

Seventy-two patients (44%) showed CAF+, while fifty-seven patients (35%) showed CD61+. Several strong positive correlations were found, including CD61+ with blood platelet count before surgery (P=0.004), and CAF+ with CD61+ (P=0.048). Patients with CAF+, CD61+ or platelet count >280×10⁹/L before surgery had a significantly shorter disease-free survival according to univariate analysis. Multivariable analysis showed that CAF+ was an independent prognostic factor (Hazard ratio=3.928; p=0.005).

CONCLUSIONS

CAF+ and CD61+ were found to be good negative prognosis factors for invasive breast cancer patients. CD61+ also had strong positive correlation with blood platelet count before surgery. These targets may be used as strategies for the treatment of breast cancer in the future.

Targeting Activated Platelets: A Unique and Potentially Universal Approach for Cancer Imaging

Rationale The early detection of primary tumours and metastatic disease is vital for successful therapy and is contingent upon highly specific molecular markers and sensitive, non-invasive imaging techniques. We hypothesized that the accumulation of activated platelets within tumours is a general phenomenon and thus represents a novel means for the molecular imaging of cancer. Here we investigate a unique single chain antibody (scFv), which specifically targets activated platelets, as a novel biotechnological tool for molecular imaging of cancer.

Methods The scFv_GPIIb/IIIa, which binds specifically to the activated form of the platelet integrin receptor GPIIb/IIIa present on activated platelets, was conjugated to either Cy7, ⁶⁴Cu or ultrasound-enhancing microbubbles. Using the Cy7 labelled scFv_GPIIb/IIIa, fluorescence imaging was performed in mice bearing four different human tumour xenograft models; SKBr3, MDA-MB-231, Ramos and HT-1080 cells. Molecular imaging via PET and ultrasound was performed using the scFv_GPIIb/IIIa-⁶⁴Cu and scFv_GPIIb/IIIa-microbubbles, respectively, to further confirm specific targeting of scFv_GPIIb/IIIa to activated platelets in the tumour stroma.

Results Using scFv_GPIIb/IIIa we successfully showed specific targeting of activated platelets within the microenvironment of human tumour xenografts models via three different molecular imaging modalities. The presence of platelets within the tumour microenvironment, and as such their relevance as a molecular target epitope in cancer was further confirmed via immunofluorescence of human tumour sections of various cancer types, thus validating the translational importance of our novel approach to human disease.

Conclusion Our study provides proof of concept for imaging and localization of tumours by molecular targeting activated platelets. We illustrate the utility of a unique scFv as a versatile biotechnological tool which can be conjugated to various contrast agents for molecular imaging of cancer using three different imaging modalities. These findings warrant further development of this activated platelet specific scFv_GPIIb/IIIa, potentially as a universal marker for cancer diagnosis and ultimately for drug delivery in an innovative theranostic approach.

Platelet "first responders" in wound response, cancer, and metastasis

Platelets serve as "first responders" during normal wounding and homeostasis. Arising from bone marrow stem cell lineage megakaryocytes, anucleate platelets can influence inflammation and immune regulation. Biophysically, platelets are optimized due to size and discoid morphology to distribute near vessel walls, monitor vascular integrity, and initiate quick responses to vascular lesions. Adhesion receptors linked to a highly reactive filopodia-generating cytoskeleton maximizes their vascular surface contact allowing rapid response capabilities. Functionally, platelets normally initiate rapid clotting, vasoconstriction, inflammation, and wound biology that leads to sterilization, tissue repair, and resolution. Platelets also are among the first to sense, phagocytize, decorate, or react to pathogens in the circulation. These platelet first responder properties are commandeered during chronic inflammation, cancer progression, and metastasis. Leaky or inflammatory reaction blood vessel genesis during carcinogenesis provides opportunities for platelet invasion into tumors. Cancer is thought of as a non-healing or chronic wound that can be actively aided by platelet mitogenic properties to stimulate tumor growth. This growth ultimately outstrips circulatory support leads to angiogenesis and intravasation of tumor cells into the blood stream. Circulating tumor cells reengage additional platelets, which facilitates tumor cell adhesion, arrest and extravasation, and metastasis. This process, along with the hypercoagulable states associated with malignancy, is amplified by IL6 production in tumors that stimulate liver thrombopoietin production and elevates circulating platelet numbers by thrombopoiesis in the bone marrow. These complex interactions and the "first responder" role of platelets during diverse physiologic stresses provide a useful therapeutic target that deserves further exploration.

Thromboelastometry hypercoagulable profiles and portal vein thrombosis in cirrhotic patients with hepatocellular carcinoma

BACKGROUND

Cirrhotic patients with hepatocellular carcinoma (HCC) exhibit hypercoagulability.

AIM

We investigated whether thromboelastometry can detect hypercoagulability in these patients and the association with portal vein thrombosis (PVT).

METHODS

At baseline, cirrhotic patients with and without HCC underwent thromboelastometry. PVT onset was recorded over a 12-month follow-up period.

RESULTS

Seventy-six patients (41 with and 35 without HCC) were included. Vital tumor volume (VTV) was  >5cm³ in 18 patients. Fibrinogen was higher in HCC patients with VTV>5cm³ as compared to those with VTV≤5cm³ and those without HCC. Mean platelet count was significantly increased in HCC patients compared with non-HCC. At baseline thromboelastometry, HCC patients showed shorter CTF and higher MCF than non-HCC. PVT incidence was 24,4% and 11.4% in patients with (10/41) and without (4/35) HCC, respectively. Among HCC, 50% of PVT occurred in Child A patients. In HCC, FIBTEM MCF>25mm was associated with a 5-fold increased PVT risk [RR: 4.8 (2-11.3); p=0.0001]. Cox multivariate analysis confirmed HCC and increased MCF (FIBTEM) to be independently associated with increased PVT risk.

CONCLUSIONS

Hypercoagulability in HCC which can be detected by thromboelastometry is associated with increased risk of PVT even in Child A patients. The clinical implication of these findings deserves further investigation.

Thrombopoietin Secretion by Human Ovarian Cancer Cells

The thrombopoietin (TPO) gene expression in human ovary and cancer cells from patients with ovarian carcinomatosis, as well as several cancer cell lines including MDA-MB231 (breast cancer), K562 and HL60 (Leukemic cells), OVCAR-3NIH and SKOV-3 (ovarian cancer), was performed using RT PCR, real-time PCR, and gene sequencing. Human liver tissues are used as controls. The presence of TPO in the cells and its regulation by activated protein C were explored by flow cytometry. TPO content of cell extract as well as plasma of a patient with ovarian cancer was evaluated by ELISA. The functionality of TPO was performed in coculture on the basis of the viability of a TPO-dependent cell line (Ba/F3), MTT assay, and Annexin-V labeling. As in liver, ovarian tissues and all cancer cells lines except the MDA-MB231 express the three TPO-1 (full length TPO), TPO-2 (12 bp deletion), and TPO-3 (116 pb deletion) variants. Primary ovarian cancer cells as well as cancer cell lines produce TPO. The thrombopoietin production by OVCAR-3 increased when cells are stimulated by aPC. OVCAR-3 cell's supernatant can replace exogenous TPO and inhibited TPO-dependent cell line (Ba/F3) apoptosis. The thrombopoietin produced by tumor may have a direct effect on thrombocytosis/thrombosis occurrence in patients with ovarian cancer.

Undercover Agents: Targeting Tumours with Modified Platelets

Platelets have long been recognised to colocalise with tumour cells throughout haematogenous metastasis. Interactions between these cells contribute to tumour cell survival and motility through the vasculature into other tissues. Now, the research focus is shifting towards developing means to exploit this relationship to provide accurate diagnostics and therapies. Alterations to platelet count, RNA profile, and platelet ultrastructure are associated with the presence of certain malignancies, and may be used for cancer detection. Additionally, nanoparticle-based drug delivery systems are enhanced through the use of platelet membranes to specifically target cancer cells and camouflage the foreign particles from the immune system. This review discusses the development of platelets into highly powerful tools for cancer diagnostics and therapies.

Investigating Preoperative Hematologic Markers for Prediction of Ovarian Cancer Surgical Outcome

PURPOSE

The current study aimed at assessing the association between neutrophil-lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) for the prognosis of the surgical outcome of epithelial ovarian cancer (EOC).

MATERIALS AND METHODS

EOC patient medical records of surgical operations between January, 2005 and December, 2015 were reviewed and their data of clinicopathological complete blood counts (CBCs) and surgical outcomes were collected. To assess their effects on surgical outcomes, PLR and NLR optimal predictive values were determined and then compared with each other.

RESULTS

A statistically significant relation was found between surgical outcomes and NLR and PLR (p<0.001 and p<0.001), for which new cutoff points were gained (PLR: 192,3,293; NLR: 3). The sensitivity and specificity were 0.74 and 0.67, respectively for PLR and 0.74 and 0.58, for NLR.

CONCLUSIONS

NLR and PLR seem to be useful methods for the prediction of surgical outcomes in patients with EOCs. Increased NLR and PLR proved to be beneficial for poor surgical outcomes. Moreover, PLR increase showed further help in the predicting outcome of EOC suboptimal debulking.

Pre-treatment platelet counts as a prognostic and predictive factor in stage II and III rectal adenocarcinoma

AIM

To investigate if pre-treatment platelet counts could provide prognostic information in patients with rectal adenocarcinoma that received neo-adjuvant treatment.

METHODS

Platelet number on diagnosis of stage II and III rectal cancer was evaluated in 51 patients receiving neo-adjuvant treatment and for whom there were complete follow-up data on progression and survival, as well as pathologic outcome at the time of surgery. Pathologic responses on the surgical specimen of patients with lower platelet counts (150-300 × 10⁹/L) were compared with these of patients with higher platelet counts (> 300 × 10⁹/L) by the χ² test. Overall and progression free survival Kaplan-Meier curves of the two groups were constructed and compared with the Log-Rank test.

RESULTS

A significant difference was present between the two groups in regards to pathologic response with patients with lower platelet counts being more likely to exhibit a good or complete response to neo-adjuvant treatment than patients with higher platelet counts (P = 0.015). Among other factors evaluated, there was also a significant difference between the carcinoembryonic antigen (CEA) at presentation of patients that exhibited a good or complete response and those that had no response or a minimal to moderate response. Patients with a good or complete response were more likely to present with a CEA of less than 5 μg/L (P = 0.00066). There was no significant difference in overall and progression free survival between the two platelet count groups (Log-Rank tests P = 0.42 and P = 0.35, respectively).

CONCLUSION

In this retrospective analysis of stage II and III rectal cancer patients, platelet counts at the time of diagnosis had prognostic value for neo-adjuvant treatment pathologic response. Pre-treatment CEA also held prognostic value in regards to treatment effect.