The changes of blood platelet activation in breast cancer patients before surgery, after surgery, and in various phases of the chemotherapy

A Three-Dimensional Microfluidic Device for Monitoring Cancer and Chemotherapy-Associated Platelet Activation

Platelet activation and the risk of thrombosis are increased in cancer patients, especially after chemotherapy. Our previous studies indicated that chemotherapy-induced platelet activation is largely due to endothelial cell damage. Thus, simple in vitro tests, such as aggregometry, are not desirable tests to predict platelet responsiveness to different chemotherapeutic agents because other contributory factors, such as tumor cells, endothelial cells, and the flow rate of platelets, also contribute to the formation of cancer-associated thrombosis. Therefore, developing a platelet detection system, which includes all possible risk parameters, is necessary. In the present study, we described a microengineered microfluidic system that contained a drug concentration generator, cancer cell culture chip, and three-dimensional (3D) circular microvascular model covered with a confluent endothelial layer and perfused with human platelets at a stable flow rate. Doxorubicin was injected through two injection sites. Endothelial cell injury was evaluated by counting, cell cytoskeleton observation, and the level of IACM1 and ET-1 in endothelial cells or a culture medium. Prestained platelets were perfused into the artificial blood vessel, and platelet-endothelial cell adhesion was measured. We found that (i) MCF7 cell-released factors had a cytotoxicity effect on both endothelial cells and platelets. (ii) We confirmed that doxorubicin-induced platelet activation was endothelial cell-dependent. (iii) A lower dosage of doxorubicin (0-2.0 μM) induced platelet activation, while a higher dosage of doxorubicin (2.0-4.0 μM) led to platelet death. Our findings indicated that platelet-endothelial cell adhesion could be used as a diagnostic marker of platelet activation, providing a simple and rapid detective way to predict platelet responsiveness before or during chemotherapy.

Development and Validation of a Novel Nomogram for Predicting Tumor-Distant-Metastasis in Patients with Early T1-2 Stage Lung Adenocarcinoma

Background

Distant metastasis in early T1-2 (diameter≤5 cm) stage lung adenocarcinoma (ET-LUAD) patients largely affect treatment strategies in clinical practice. However, the associated mechanism remains unclear and related studies is less. This study aimed to establish and validate a novel nomogram to predict the risk of distant metastasis in ET-LUAD.

Methods

A total of 258 patients diagnosed with ET-LUAD and not receiving any treatment were recruited into this study. The patients were randomly divided into a training cohort and validation cohort in a ratio of 1:2. Univariate and multivariate logistic regression analysis was used to select the most significant predictive risk factors associated with distant metastasis in the training cohort. The established nomogram was validated by the consistency index (C-index), calibration curve, and decision curve analysis (DCA).

Results

There were 124 patients with confirmed distant metastasis and 134 patients with non-distant metastases ET-LUAD were enrolled in the study. Multivariate logistic hazards regression analysis identified independent risk factors associated with distant metastasis to include platelet-to-lymphocyte ratios (PLR), lactate dehydrogenase (LDH), neural-specific enolase (NSE), carcinoembryonic antigen (CEA) and cytokeratin 19 fragments (Cyfra211), which were included in the establishment of the nomogram. The nomogram achieved a high consistency (C-index=0.792), good calibration, and high clinical application value in the validation cohort.

Conclusion

The established nomogram can be used to predict distant metastasis in high-risk ET-LUAD nonmetastasis patients and can also be used by doctors to guide preventive and individualized treatment for ET-LUAD patients.

Doxorubicin contributes to thrombus formation and vascular injury by interfering with platelet function

In clinical studies, platelet aggregation and risk of thrombosis are increased in patients after doxorubicin treatment. However, the exact role of doxorubicin in platelet functions and thrombus formation in vivo remain unclear. The present study is to investigate the role of doxorubicin in platelet function in relation to thrombus formation and vascular toxicity, as well as the efficacy of antiplatelet therapy. Mice were treated with doxorubicin or vehicle (5 mg/kg iv, 4 wk), and the following parameters were determined: platelet count and size, platelet surface adhesive receptors by flow cytometry, density of granules by electron microscopy, platelet aggregation and degranulation at resting or agonist-stimulated state, platelet adhesion on fibrinogen or endothelial cells, and thrombus formation on collagen matrix. The efficacy of clopidogrel (15 mg·kg^-1·day^-1, followed by 5 mg·kg^-1·day^-1) on doxorubicin-induced changes in the aforementioned parameters as well as vascular injury were also determined. Whereas platelet count and size were similar between doxorubicin-treated and vehicle-treated mice, doxorubicin promoted thrombus formation evidenced by greater platelet aggregation, degranulation, and adhesion to endothelial cells evoked by agonists. Clopidogrel treatment attenuated the enhanced platelet activity and thrombus formation by doxorubicin, as well as vascular platelet infiltration and reactive oxygen species generation. Collectively, this study demonstrates that platelet functions are enhanced after long-term doxorubicin administration, which leads to thrombus formation and vascular toxicity, and that doxorubicin-induced changes in the functionality of platelets can be effectively inhibited by antiplatelet drugs.NEW & NOTEWORTHY Doxorubicin therapy in mice (antitumor dosage) markedly enhanced platelet functions measured as agonist-induced platelet aggregation, degranulation, and adhesion to endothelial cells, actions leading to thrombus formation and thrombosis-independent vascular injury. Clopidogrel treatment ameliorated thrombus formation and vascular toxicity induced by doxorubicin via inhibiting platelet activity.

Platelet function in lung cancer patients undergoing lobectomy

A growing interest concerns arterial thromboembolic disease in cancer patients. As platelets may be key players in this process, investigation of platelet aggregation in cancer patients is of importance. We aimed to investigate platelet aggregation in patients with lung cancer prior to surgery and during video-assisted thoracoscopic surgery (VATS) lobectomy compared with lobectomy performed through a thoracotomy. We included 93 patients (VATS + low molecular weight heparin (LMWH), n = 32; VATS no LMWH, n = 31; thoracotomy + LMWH, n = 30). Data obtained from 121 healthy individuals were used for comparison prior to surgery. Platelet aggregation was analysed by impedance aggregometry using adenosine diphosphate 6.5 μM (ADPtest) and collagen 3.2 μg/mL (COLtest) as agonists. Prior to surgery, platelet aggregation was significantly increased in both VATS-patients (ADPtest, p < .0001; COLtest, p = .0002) and patients undergoing thoracotomy (ADPtest, p < .0001; COLtest, p < .0001) compared with healthy individuals. Platelet aggregation did not differ between VATS-patients and thoracotomy patients prior to surgery (p-values >.11). At the first postoperative day, VATS-patients demonstrated significantly higher collagen-induced platelet aggregation than preoperatively (p = .001), but the increase in platelet aggregation did not differ significantly between VATS and thoracotomy patients (p-values ≥.24). At the second postoperative day, platelet aggregation was significantly reduced in thoracotomy patients compared with the preoperative level (ADPtest, p = .002; COLtest, p = .05). In conclusion, platelet aggregation was significantly increased in patients with primary lung cancer prior to surgery compared with healthy individuals. At the first postoperative day, platelet aggregation was significantly higher than the preoperative level in VATS-patients; however, this increase did not differ between patient groups.

Breast cancer cell-induced platelet activation is compounded by tamoxifen and anastrozole in vitro

Platelet-tumour cell interaction is implicated in the initiation of breast cancer-associated thrombosis, with hormone-therapy (Tamoxifen/Anastrozole), increasing this risk. However, recent in vitro research indicates that Tamoxifen inhibits platelet activation, while the effects of Anastrozole on platelet activation are not well characterised. This study investigated platelet activation caused by Tamoxifen or Anastrozole-treated breast cancer cells in vitro. MCF7 and T47D cells were pre-treated with Tamoxifen or Anastrozole to mimic the effects of the drugs in vivo, and co-cultured with whole blood. Platelet activation was determined using flow cytometry. Platelet (CD41a⁺CD62P⁺) was determined using an interval gating strategy. Platelet morphology was visualised using scanning electron microscopy. Our results support clinical findings, showing that hormone-therapy is associated with platelet activation. Tamoxifen-treated MCF7 cells increased P-selectin expression, with ultrastructural analysis showing fully spread platelets. Conversely, Tamoxifen-treated T47D cells decreased P-selectin expression with platelets showing signs of early aggregation. Anastrozole pre-treatment decreased P-selectin expression, with treated MCF7 cells inducing platelet membrane folds and lamellipodia extension, and treated T47D cells inducing platelet aggregation and fibrin network formation indicating hypercoagulation. The findings support clinical studies. Hormone-therapy augments tumour cell-induced platelet activation, which may be linked to cell phenotype. This may have clinical implications for treatment strategies.

Adjuvant radiotherapy does not affect hemostasis

Cancer is associated with increased risk of venous thromboembolic disease. Venous thromboembolic disease accounts for a substantial addition to morbidity and mortality rates in cancer patients and is the second leading cause of death in cancer patients, exceeded only by the underlying cancer. Only few previous studies have investigated the influence of radiotherapy on hemostasis and whether radiotherapy in itself causes an increased risk of venous thromboembolic disease. The aim was to investigate if adjuvant radiotherapy affects hemostasis after surgery and chemotherapy in patients with breast cancer. Radiotherapy consisted of either 40 Gy/15 fractions or 50 Gy/25 fractions. Blood samples were obtained from 39 consecutive women before and immediately after the first, the intermediate, and the final radiation fraction. Platelet function was measured using impedance aggregometry, and thrombin generation was determined in platelet-poor plasma using calibrated automated thrombogram. Furthermore, P-selectin, international normalized ratio, fibrinogen, activated partial thromboplastin time, coagulation factor VIII, von Willebrand factor, C-reactive protein (CRP), and soluble thrombomodulin were measured before and after radiation treatment. Platelet aggregation was within reference interval before initiation of radiotherapy, and remained unaffected during the radiation course. Neither serum P-selectin, thrombin generation, fibrinogen, coagulation factor VIII, von Willebrand factor, CRP nor thrombomodulin were substantially influenced by radiation treatment. The present study showed that radiotherapy did not affect hemostasis, neither by a single radiation dose nor during the radiation course, in early breast cancer patients receiving adjuvant radiotherapy.

Prognostic and clinicopathological significance of platelet to lymphocyte ratio in esophageal cancer: a meta-analysis

Background

The prognostic and clinicopathological significance of the platelet to lymphocyte ratio (PLR) has been studied in various cancers. However, studies examining the role of PLR in esophageal cancer have not yielded consistent results. The purpose of this meta-analysis was to study the prognostic and clinicopathological significance of PLR in esophageal cancer patients.

Methods

We performed a literature search in three major databases: PubMed, Web of Science and Embase (up until May 1, 2017). The clinicopathologic significance of PLR and its prognostic significance were analyzed.

Results

Our meta-analysis consisted of 13 studies with 4,621 patients. The pooled hazard ratios (HRs) showed that a high PLR was associated with poor survival of esophageal cancer [HR =1.283; 95% confidence interval (CI): 1.173-1.404; P<0.001]. Subgroup analysis revealed that elevated PLR was associated with poor survival in esophageal squamous cell carcinoma (HR =1.281; 95% CI: 1.098-1.493; P=0.002). The pooled odds ratio (OR) indicated that high PLR was also associated with the depth of tumor invasion (OR =1.543, 95% CI: 1.269-1.876, P<0.001), lymph node metastasis (OR =1.427, 95% CI: 1.195-1.705, P<0.001), tumor length (OR =1.81, 95% CI: 1.331-2.461, P<0.001), and Tumor stage (OR =1.459, 95% CI: 1.235-1.724, P<0.001).

Conclusions

Our results demonstrate that elevated PLR was significantly associated with poor prognosis of esophageal cancer. Furthermore, the high PLR might predict worse clinicopathological features of esophageal cancer patients.

Platelets in cancer and thrombosis

Platelets are the smallest circulating blood cells and their major function is the maintenance of haemostasis. They do not have a nucleus, but instead a multitude of granules that contain molecules important for several physiological processes. These granules can be released after platelet activation and thereby platelets take part in haemostasis, wound repair or immunological processes. Furthermore, platelets are also involved in the pathophysiology of several diseases, including cancer. Platelets can support various steps of cancer development and progression by promoting tumour growth, angiogenesis and metastasis. Moreover, platelets contribute to the hypercoagulable state frequently observed in cancer patients, leading to an increased risk of venous thromboembolism (VTE). In previous studies a high platelet count was repeatedly found to be associated with an elevated risk of VTE and a worse prognosis in patients with cancer.

The aim of this review is to give an overview of the most important alterations of platelet physiology in cancer patients and how these alterations may influence cancer disease and contribute to cancer-associated VTE.

Venous thromboembolic events in lymphoma patients: Actual relationships between epidemiology, mechanisms, clinical profile and treatment

Venous thromboembolic events (VTE) are an underestimated health problem in patients with lymphoma. Many factors contribute to the pathogenesis of thromboembolism and the interplay between various mechanisms that provoke VTE is still poorly understood. The identification of parameters that are associated with an increased risk of VTE in lymphoma patients led to the creation of several risk-assessment models. The models that evaluate potential VTE risk in lymphoma patients in particular are quite limited, and have to be validated in larger study populations. Furthermore, the VTE prophylaxis in lymphoma patients is largely underused, despite the incidence of VTE. The lack of adequate guidelines for the prophylaxis and treatment of VTE in lymphoma patients, together with a cautious approach due to an increased risk of bleeding, demands great efforts to ensure the implementation of current knowledge in order to reduce the incidence and complications of VTE in lymphoma patients.

The Potential Role of Senescence As a Modulator of Platelets and Tumorigenesis

In addition to thrombus formation, alterations in platelet function are frequently observed in cancer patients. Importantly, both thrombus and tumor formation are influenced by age, although the mechanisms through which physiological aging modulates these processes remain poorly understood. In this context, the potential effects of senescent cells on platelet function represent pathophysiological mechanisms that deserve further exploration. Cellular senescence has traditionally been viewed as a barrier to tumorigenesis. However, far from being passive bystanders, senescent cells are metabolically active and able to secrete a variety of soluble and insoluble factors. This feature, known as the senescence-associated secretory phenotype (SASP), may provide senescent cells with the capacity to modify the tissue environment and, paradoxically, promote proliferation and neoplastic transformation of neighboring cells. In fact, the SASP-dependent ability of senescent cells to enhance tumorigenesis has been confirmed in cellular systems involving epithelial cells and fibroblasts, leaving open the question as to whether similar interactions can be extended to other cellular contexts. In this review, we discuss the diverse functions of platelets in tumorigenesis and suggest the possibility that senescent cells might also influence tumorigenesis through their ability to modulate the functional status of platelets through the SASP.

Cancer antigen 15-3, platelet distribution width, and fibrinogen in combination to distinguish breast cancer from benign breast disease in non-conclusive mammography patients

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females. However, mammographic diagnosis is sometimes non-conclusive with a Breast imaging Reporting and Data System (Bi-RaDS) result of 0. Cancer antigen 15-3 (CA15-3) is the most widely used serum tumor marker for breast cancer screening. Platelet distribution width (PDW) is an early indicator of platelet activation. Fibrinogen contributed to angiogenesis and distant metastasis. The aim of this study was to investigate the ability of CA15-3, PDW, and fibrinogen individually or in combination, to distinguish breast cancer from benign breast disease. 200 consecutive patients with breast cancer and 187 patients with benign breast disease were included in this retrospective study. Patients’ characteristics and hematologic tests data at initial diagnosis were collected. The benefit of adding PDW and fibrinogen to a model with only CA15-3 was evaluated as an increased in the area under the curve (AUC) obtained by receiver operating curve (ROC). CA15-3, PDW and fibrinogen are higher in breast cancer patients than in patients with benign breast disease. Single biomarkers had AUC values ranging from 0.687 for fibrinogen to 0.810 for CA15-3. In addition, the combination of PDW, CA15-3, and fibrinogen increased the AUC to 0.900 (0.866-0.928) (p<0.0001), significantly higher than those of any single marker. In conclusion, the combined use of CA15-3, PDW and fibrinogen may be clinically useful in discriminating between breast cancer and benign breast disease in non-conclusive mammography patients.

Sevoflurane attenuates platelets activation of patients undergoing lung cancer surgery and suppresses platelets-induced invasion of lung cancer cells

STUDY OBJECTIVE

Platelets play a pivotal role in metastasis of tumor cells. The aim of this study is to explore the effects of sevoflurane and isoflurane on platelets activation of patients undergoing lung cancer surgery, and the effects of sevoflurane and isoflurane on platelets-induced invasion of lung cancer cells.

DESIGN

Prospective and randomized study, and in vitro experiment.

SETTING

University-affiliated teaching hospital and laboratory.

PATIENTS

Forty-six patients scheduled for lung cancer radical surgery.

INTERVENTIONS

Patients were randomized to two groups of 23 patients each and were received sevoflurane (group SEV) or isoflurane (group ISO) during surgery, respectively. In vitro, lung cancer cells were treated with platelets in the presence or absence anesthetics.

MEASUREMENTS

Platelets activation were determined by detecting glycoproteinIIb/IIIa (GPIIb/IIIa), CD62P, and platelets aggregation rate (PAR) pre-, intra-, and postoperatively. Invasion ability of lung cancer cells were evaluated by Transwell assay.

RESULTS

The levels of GPIIb/IIIa, CD62P, and PAR were reduced markedly in group SEV during perioperative period compared with group ISO. In vitro, activated platelets contributed profoundly to the invasive ability of lung cancer cells. Sevoflurane, but not isoflurane, inhibited platelets-induced invasion of lung cancer cells. Furthermore, sevoflurane suppressed the platelets activity in vitro.

CONCLUSION

Sevoflurane attenuates platelets activation of patients undergoing lung cancer surgery. In vitro, sevoflurane suppresses platelets-induced invasion of lung cancer cells via decreasing platelets activity.

Platelet phenotype changes associated with breast cancer and its treatment

Platelets and their granular contents influence both angiogenesis and breast cancer progression. This study was performed to assess the effect of breast cancer and its treatment on platelet biology and the response to inhibition of the platelet P2Y12 receptor. Receptor-specific platelet activation and inhibition was studied for three platelet-associated proteins important in cancer angiogenesis and progression, vascular endothelial growth factor (VEGF), thrombospondin1 (TSP1), and transforming growth factor beta 1 (TGF-β1). Twenty-four women with active breast cancer and 10 healthy controls not receiving antiplatelet therapy participated in the study. Ex vivo activation of platelets in whole blood was accomplished using PAR1AP, PAR4AP, convulxin, and ADP. Platelet inhibition was accomplished using the P2Y12 receptor antagonist cangrelor (the in vitro equivalent of clopidogrel). VEGF, TSP1, and TGF-β1 were measured using standard ELISA. Platelet activation by ADP, PAR1, PAR4, and collagen receptors increased VEGF, TSP1, and TGF-β1 secretion in patients with breast cancer. Agonist-induced release of VEGF was greater in cancer patients as compared to healthy controls (p = 0.02 for ADP, p < 0.001 for PAR1AP, PAR4AP, and convulxin) despite a decrease in the efficiency of VEGF secretion in patients with breast cancer. These differences were not observed for TSP1 and TGF-β1 secretion. P2Y12 receptor inhibition decreased VEGF, TSP1, and TGF-β1 secretion. In patients with cancer, cangrelor inhibited TSP1 release to a greater extent than VEGF and TGF-β1 release. In patients with breast cancer, the magnitude of platelet inhibition achieved by cangrelor was greater than that achieved with healthy controls for all agonists and platelet proteins studied. While platelets are known to influence progression of breast cancer, our results show that breast cancer and its treatment influence the platelet phenotype by increasing the secretion of pro-angiogenic proteins following platelet activation, modulating the efficiency of platelet protein release as well as increasing the response to antiplatelet therapy.

Hydroxyethyl starch 200/0.5 decreases circulating tumor cells of colorectal cancer patients and reduces metastatic potential of colon cancer cell line through inhibiting platelets activation

Platelets play an important role in metastasis of circulating tumor cells (CTCs). It has been demonstrated that hydroxyethyl starch (HES) inhibits platelets function. However, the effect of HES on CTCs in patients with colorectal cancer remains unclear. We compared the effects of HES 200/0.5 and HES 130/0.4 on CTCs and platelets activation of colorectal patients in this study. Additionally, the effects of HES 200/0.5 or HES 130/0.4 on metastasis ability of colon cancer cell line that stimulated by activated platelets have been explored. In vivo, 90 patients undergoing colorectal cancer radical surgery received randomly 15 mL/kg of HES 200/0.5 (n = 45) or HES 130/0.4 (n = 45) infusion before surgery. Platelet glycoprotein IIb/IIIa (GPIIb/IIIa), CD62P and platelets aggregation rate (PAR) were evaluated pre-, intra- and postoperatively. Cytokeratin-20 (CK-20) mRNA was detected by reverse transcriptase polymerase chain reaction before and after surgery. In vitro, colon cancer SW480 cells were incubated with activated platelets in the presence or absence HES 200/0.5 or HES 130/0.4. The metastasis ability of SW480 cells was assessed by Transwell assay. The results showed that CK-20 mRNA positive rate in HES 200/0.5 group after surgery was decreased significantly as compared to group HES 130/0.4 (χ (2) = 6.164, P = 0.013). Simultaneously, a more pronounced inhibition of platelets activation was observed in group HES 200/0.5. A positive correlation between platelets activation marker and CK-20 mRNA positive rate was found. In vitro, HES 200/0.5, but not HES 130/0.4, decreased the invasion and migration ability of SW480 cells that induced by activated platelets. Besides, the expression of GPIIb/IIIa, CD62P and PAR was inhibited more strongly in group HES 200/0.5 than those in group HES 130/0.4. In summary, we found that HES 200/0.5 significantly decreased CTCs of patients undergoing colorectal cancer radical surgery as compared to HES 130/0.4, which might be associated with inhibiting platelets activation of HES 200/0.5. Furthermore, HES 200/0.5, but not HES 130/0.4, reduced the metastatic potential of colon cell line stimulated by activated platelets through depressing platelets activation. Modulation of platelets activity may be a novel strategy to minimize the risk of metastasis during surgery.

Evaluation of antitumor activity of platelet microbicidal protein on the model of transplanted breast cancer in CBRB-Rb(8.17)1Iem mice

Breast cancer is the most common women's cancer in the world. There is considerable current interest in developing anticancer agents with a new mode of action because of the development of resistance by cancer cells towards current anticancer drugs. Mamalian cells have been shown to contain small, cationic, microbicidal peptides. Antimicrobial peptides have drawn attention as a promising alternative to current antitumor agents. Such peptides have been isolated both from animal and human platelets and have been termed platelets microbicidal proteins (PMP). The aim of this work was to study antitumor activity of PMP in vivo on the model of mouse breast cancer in comparison with antitumor hexapeptide Arg-alpha-Asp-Lys-Val-Tyr-Arg (Immunofan). We demonstrated that the tumors treated with PMP were significant smaller than the control groups (P < 0.05). In experiments in vivo using CBRB-Rb(8.17)1Iem mice with transplanted tumors PMP inhibited tumor growth during the treatments and after its discontinuation. These findings indicate that PMP can exert antitumor effects. Therefore, PMP may be used for the development of therapy for the intervention of breast cancer.