Aggressive chronic platelet inhibition with prasugrel and increased cancer risks: revising oral antiplatelet regimens?

de Pancorbo M, Palencia-Madrid L, Garcia-Etxebarria K, Rocandio AM, Arroyo-Izaga M. Gene-Diet Interactions in Colorectal Cancer: Survey Design, Instruments, Participants and Descriptive Data of a Case-Control Study in the Basque Country

Epidemiologic studies have revealed inconsistent evidence of gene-diet interaction in relation to colorectal cancer (CRC). The aim of this study was to analyze them in a sample of cases and controls from the population-based bowel cancer screening program of the Osakidetza/Basque Health Service. This study analyzed dietetic, genetic, demographic, socioeconomic factors and lifestyles. In the present manuscript, the survey design, sampling, instruments, measurements and related quality management were presented. Moreover, we analyze differences between cases and controls in some data, especially those related to diet. The participants were 308 cases and 308 age- and sex-matched subjects as controls. Cases were more likely than controls to have overweight/obesity (67.5% vs. 58.1%, p < 0.05), a lower intake of vitamin B2 (0.86 ± 0.23 vs. 0.92 ± 0.23 mg/1000 kcal, p < 0.01) and calcium:phosphorus ratio (0.62 ± 0.12 vs. 0.65 ± 0.13, p < 0.01). A higher proportion of cases than controls did not meet the Nutritional Objectives for saturated fatty acids (85.7% vs. 67.5%, p < 0.001) or cholesterol (35.4% vs. 25.0%, p < 0.01). In conclusion, the present study provides valuable data for analyzing the complexity of gene-diet interaction in relation to CRC. The results presented here suggest that overweight/obesity and a high intake of certain dietary components, especially saturated fatty acids and cholesterol, are more frequent in cases than in controls.

Impact of Clopidogrel Therapy on Mortality and Cancer in Patients With Cardiovascular and Cerebrovascular Disease: A Patient-Level Meta-Analysis

BACKGROUND

Clinical trial data associate extended clopidogrel therapy with increased mortality and cancer. We sought to determine the impact of continued clopidogrel use on mortality and cancer within a patient-level meta-analysis of randomized clinical trials.

METHODS AND RESULTS

Meta-analytic clinical event rates for all-cause, cardiovascular, noncardiovascular, and cancer-related mortality; cancer; myocardial infarction; stroke; and fatal and major nonfatal bleeding were generated using patient-level data from 6 randomized trials comparing prolonged versus no or short-duration clopidogrel on a background of aspirin in patients with cardiovascular and cerebrovascular disease. Among 48 817 randomized patients (median follow-up 546 days), there was no difference in all-cause (7.23% versus 7.26%; P=0.97), cardiovascular (5.25% versus 5.22%; P=0.86), noncardiovascular (1.98% versus 2.03%; P=0.73), and cancer-related (0.93% versus 0.99%; P=0.59) mortality or in new cancer diagnoses (2.97% versus 2.96%; P>0.99). Rates of myocardial infarction (3.21% versus 4.05%; P<0.0001) and stroke (3.04% versus 3.75%; P<0.0001) were significantly lower in patients receiving continued clopidogrel. Fatal bleeding was more common with continued clopidogrel use (0.39% versus 0.27%; P=0.03), as were major nonfatal bleeding (4.06% versus 2.68%; P<0.0001) and intracranial hemorrhage (0.43% versus 0.30%; P=0.02).

CONCLUSIONS

Across trials of cardiovascular and cerebrovascular disease, extended-duration clopidogrel on a background of aspirin has no overall effect on mortality or cancer but does reduce rates of myocardial infarction and stroke and increase rates of bleeding. These findings emphasize the need for selective use of extended clopidogrel therapy in patients in whom the risks of ischemia are not fully counterbalanced by the risks of bleeding.

Cancer and platelet crosstalk: opportunities and challenges for aspirin and other antiplatelet agents

Platelets have long been recognized as key players in hemostasis and thrombosis; however, growing evidence suggests that they are also significantly involved in cancer, the second leading cause of mortality worldwide. Preclinical and clinical studies showed that tumorigenesis and metastasis can be promoted by platelets through a wide variety of crosstalk between platelets and cancer cells. For example, cancer changes platelet behavior by directly inducing tumor-platelet aggregates, triggering platelet granule and extracellular vesicle release, altering platelet phenotype and platelet RNA profiles, and enhancing thrombopoiesis. Reciprocally, platelets reinforce tumor growth with proliferation signals, antiapoptotic effect, and angiogenic factors. Platelets also activate tumor invasion and sustain metastasis via inducing an invasive epithelial-mesenchymal transition phenotype of tumor cells, promoting tumor survival in circulation, tumor arrest at the endothelium, and extravasation. Furthermore, platelets assist tumors in evading immune destruction. Hence, cancer cells and platelets maintain a complex, bidirectional communication. Recently, aspirin (acetylsalicylic acid) has been recognized as a promising cancer-preventive agent. It is recommended at daily low dose by the US Preventive Services Task Force for primary prevention of colorectal cancer. The exact mechanisms of action of aspirin in chemoprevention are not very clear, but evidence has emerged that suggests a platelet-mediated effect. In this article, we will introduce how cancer changes platelets to be more cancer-friendly and highlight advances in the modes of action for aspirin in cancer prevention. We also discuss the opportunities, challenges, and opposing viewpoints on applying aspirin and other antiplatelet agents for cancer prevention and treatment.

Prasugrel hydrochloride for the treatment of acute coronary syndrome patients

INTRODUCTION

Dual antiplatelet therapy (DAPT) with aspirin combined with either a thienopyridine (clopidogrel or prasugrel) or acyclopentyl-triazolo-pyrimidine (ticagrelor) plays a vital role in the management of acute coronary syndrome (ACS) especially in those undergoing percutaneous coronary intervention (PCI) but even those being managed medically. Observational studies and some formal studies have shown patients on the standard dual antiplatelet regimen (clopidogrel and aspirin) continue to have further ischemic events and can suffer stent thrombosis. It has been demonstrated that clopidogrel is associated with a delayed onset of action with a considerable inter-individual variation to treatment thus making it difficult to achieve an optimal level of platelet inhibition. Areas covered: This article will review the current evidence that is available regarding the effectiveness and safety of prasugrel in ACS patients undergoing percutaneous coronary intervention (PCI). Expert commentary: Prasugrel is an oral third-generation inhibitor of platelet activation and aggregation. Laboratory studies and early phase clinical trials show prasugrel has a faster onset of action, is more potent and has reduced inter-patient response variability compared to clopidogrel. The published studies so far demonstrated that prasugrel when compared to clopidogrel also shows a higher degree of effectiveness in the prevention of platelet-initiated thrombotic events in patients with ACS undergoing PCI, however these benefits are offset somewhat by an increased bleeding risk.

Antithrombotic drugs, patient characteristics, and gastrointestinal bleeding: Clinical translation and areas of research

Gastrointestinal bleeding (GIB) is a potentially fatal and avoidable medical condition that poses a burden on global health care costs. Current understanding of the roles of platelet activation and thrombin generation/activity in vascular medicine has led to the development of effective antithrombotic treatments. However, in parallel with a sustained coronary and cerebral flow patency, the increasingly intensive treatment with warfarin; direct oral anticoagulant drugs [DOACs], and/or with aspirin ± clopidogrel (or ± prasugrel or ± ticagrelor), has increased the burden of GIBs related to the use of antithrombotic agents. Compelling evidence concerning this issue is accumulating to indicate that: 1) the risk of GIB related to the use of antithrombotic drugs dramatically differs in different clinical settings; and 2) the characteristics of patients (e.g., severity of illness, comorbidities) in whom it is used exert a greater impact on the risk of GIB than the type of antithrombotic agent employed. The latter concept argues for the occurrence of GIB as reflecting the presence of patients at the highest risk for adverse outcomes. The HAS-BLED score identifies subjects at risk of bleeding among those untreated and those treated with warfarin, DOACs and/or low-dose aspirin. Its use within the frame of a severity score (e.g., the CHA2DS2-VASc score in patients with atrial fibrillation) helps balance the benefits and the risks of an antithrombotic treatment and identify those patients in whom the absolute gain (vascular events prevented) outweighs the risk of GIB. Potential implications of the latter information in settings other than atrial fibrillation is thoroughly discussed.

Cardiovascular medications and risk of cancer

Cardiovascular disease and cancer are 2 of the leading causes of death globally. Certain cardiovascular medications have been linked to an increased risk for cancer. Although individual reviews of specific classes of cardiovascular medications have been published previously, a more complete review of several classes has not been performed. The aim of this review is to evaluate the associations of various cardiovascular agents with the risk for developing cancer and provide guidance for clinicians. A comprehensive search of published research was conducted using MEDLINE from 1994 to 2011. Three trials demonstrated an increased risk for cancer using angiotensin II receptor blockers. Additionally, risk for cancer was shown in a number of trials that included the use of angiotensin II receptor blockers in combination with angiotensin-converting enzyme inhibitors. Five trials suggested that diuretics increased the risk for specific cancers, especially in women and those who had been using diuretics for >4 years. Statins and ezetimibe, in contrast, did not show this increased risk. Prasugrel was shown to be associated with an increased risk for cancer in 1 study. It appears that the use of certain cardiovascular medications is associated with an increased risk for cancer. In conclusion, clinicians need to balance the risks and benefits of the use of these agents and provide the appropriate therapy on an individual basis.

Release of angiogenesis regulatory proteins from platelet alpha granules: modulation of physiologic and pathologic angiogenesis

An association between platelets, angiogenesis, and cancer has long been recognized, but the mechanisms linking them remains unclear. Platelets regulate new blood vessel growth through numerous stimulators and inhibitors of angiogenesis by several pathways, including differential exocytosis of angiogenesis regulators. Herein, we investigated the differential release of angiogenesis stimulators and inhibitors from platelets. Activation of human platelets with adenosine diphosphate (ADP) stimulated the release of VEGF, but not endostatin whereas, thromboxane A(2) (TXA(2)) released endostatin but not VEGF. Platelet releasates generated by activation with ADP promoted migration and formation of capillary structures by human umbilical vein endothelial cells (HUV-EC-Cs) in in vitro angiogenesis models. Conversely, TXA(2)-stimulated platelet releasate inhibited migration and formation of capillary structures. Because tumor growth beyond 1-2 mm(3) is angiogenesis-dependent, we hypothesized that cancer cells preferentially stimulate platelets to secrete their pro-angiogenic payload. In support of this, the breast cancer cell line MCF-7 stimulated secretion of VEGF and a pro-angiogenic releasate from platelets. Furthermore, the antiplatelet agent aspirin inhibited platelet-mediated angiogenesis after exposure to ADP or MCF-7 cells providing a potential mechanism for how aspirin may impact malignancy. Manipulation of differentially mediated release of angiogenic factors from platelets may provide a new modality for cancer treatment.

Arterial and venous thrombosis in cancer patients

The most frequent ultimate cause of death is myocardial arrest. In many cases this is due to myocardial hypoxia, generally arising from failure of the coronary macro- and microcirculation to deliver enough oxygenated red cells to the cardiomyocytes. The principle reason for this is occlusive thrombosis, either by isolated circulating thrombi, or by rupture of upstream plaque. However, an additionally serious pathology causing potentially fatal stress to the heart is extra-cardiac disease, such as pulmonary hypertension. A primary cause of the latter is pulmonary embolus, considered to be a venous thromboembolism. Whilst the thrombotic scenario has for decades been the dominating paradigm in cardiovascular disease, these issues have, until recently, been infrequently considered in cancer. However, there is now a developing view that cancer is also a thrombotic disease, and notably a disease predominantly of the venous circulation, manifesting as deep vein thrombosis and pulmonary embolism. Indeed, for many, a venous thromboembolism is one of the first symptoms of a developing cancer. Furthermore, many of the standard chemotherapies in cancer are prothrombotic. Accordingly, thromboprophylaxis in cancer with heparins or oral anticoagulation (such as Warfarin), especially in high risk groups (such as those who are immobile and on high dose chemotherapy), may be an important therapy. The objective of this communication is to summarise current views on the epidemiology and pathophysiology of arterial and venous thrombosis in cancer.

Emerging drugs for acute myocardial infarction

IMPORTANCE OF THE FIELD

The present review is aimed at going over the pharmacological profile (and the clinical impact) of the emerging drugs involved in the management of patients with ST-elevation myocardial infarction (STEMI) in order to provide the cardiologists who deal with these patients in the early phase with the most recent evidence on this topic.

AREAS COVERED IN THIS REVIEW

Anticoagulant and antiplatelet drugs are the main cornerstones of therapy in the treatment of STEMI patients undergoing primary percutaneous coronary intervention (PCI). The main issues that clinicians have to deal with are represented by balancing thrombotic and bleeding risks. In tailoring therapy, variables such as age, sex and previous disease should be taken into account, as well as ongoing complications (such as acute renal failure) that could affect hemostasis. Despite the well-established clinical benefits of antiplatelet agents, questions remain, mainly surrounding potential for variable platelet response, which are strictly related to non-genetic (i.e., diet, drug-drug interaction, clinical factors such as obesity, diabetes mellitus, and inflammation) and genetic determinants.

WHAT THE READER WILL GAIN

In their daily practice, cardiologists cannot abstract from the knowledge and updating on the ongoing research fields as well as the newly developed drugs, which they should frame in the very patient in the attempt to the develop a personalized medical strategy. These include also the pharmacological option(s) in the treatment of the reperfusion injury, the metabolic aspects and the stem cell therapy. TAKE HOME MASSAGE: In our opinion, the goal of ongoing research on the pharmacological approach to STEMI patients is a personalized medical strategy that relies on critical clinicians who merge newly developed acquisitions on this topic and a more complete, systemic and critical approach to the patient.

Prasugrel: Clinical development and therapeutic application

Dual antiplatelet therapy with aspirin and clopidogrel is a cornerstone of the management of patients with acute coronary syndromes and following percutaneous coronary intervention. Despite the proven benefits, clear limitations of clopidogrel exist. Prasugrel is a third-generation thienopyridine antiplatelet agent with pharmacologic characteristics that overcome some of the limitations of clopidogrel, but at the expense of increased bleeding. The promising results seen with prasugrel in large, randomized trials led to its recent approval by the US Food and Drug Administration for reducing thrombotic cardiovascular events in patients with acute coronary syndromes managed with percutaneous coronary intervention. This article will review the limitations of standard antiplatelet therapy and discuss the clinical application of prasugrel.