title: Increased platelet reactivity in patients with late-stage metastatic cancer.
abstract: Platelet hyperreactivity is associated with an increased risk of thrombosis. Cancer patients are at an increased risk of thrombosis, a risk that increases with disease progression. While cancer patients show evidence of platelet activation in vivo, few studies have extensively assessed whether these patients display platelet hyperreactivity. We hypothesized that patients with metastatic cancer would display platelet hyperreactivity, reflecting their associated high risk of thrombosis. In a cohort of patients with metastatic cancer (n = 13), we assessed platelet function using well-established assays of platelet reactivity (agonist-induced platelet aggregation, spontaneous platelet aggregation, and agonist-induced P-selectin expression). In comparison with healthy controls (n = 10), patients with metastatic cancer displayed global platelet hyperreactivity. Agonist-induced platelet aggregation responses to ADP (adenosine diphosphate), epinephrine, collagen, arachidonic acid, and PAR-1 (protease-activated receptor-1) activating peptide, as well as spontaneous platelet aggregation, were significantly increased in patients with metastatic cancer. Furthermore, agonist-induced platelet P-selectin expression was also significantly increased within the patient cohort. We demonstrate that patients with metastatic cancer are characterized by global platelet hyperreactivity, a factor that may contribute to their increased risk of thrombosis.
authors.affiliation: Molecular and Cellular Therapeutics, The Royal College of Surgeons in Ireland Dublin, Ireland ; The Biomedical Diagnostics Institute, Dublin City University Dublin, Ireland.
authors.forename: Niamh M
authors.initials: NM
authors.lastname: Cooke
authors.forename: Karl
authors.initials: K
authors.lastname: Egan
authors.forename: Siobhan
authors.initials: S
authors.lastname: McFadden
authors.forename: Liam
authors.initials: L
authors.lastname: Grogan
authors.forename: Oscar S
authors.initials: OS
authors.lastname: Breathnach
authors.forename: John
authors.initials: J
authors.lastname: O'Leary
authors.forename: Bryan T
authors.initials: BT
authors.lastname: Hennessy
authors.forename: Dermot
authors.initials: D
authors.lastname: Kenny
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009369:Neoplasms / Q000097:blood* / Q000150:complications / Q000473:pathology*; D015539:Platelet Activation; D010974:Platelet Aggregation; D010976:Platelet Count; D013922:Thrombocytosis / Q000209:etiology
keywords: Activation; aggregation; hyperreactivity; metastasis; platelets