The plasma miRnome and venous thromboembolism in high-grade glioma: miRNA sequencing of a nested case-control cohort

Background: Patients with high-grade gliomas are at high risk of venous thromboembolism (VTE). MicroRNAs (miRNAs) are small non-coding RNAs with multiple roles in tumor biology, hemostasis and platelet function. We aimed to explore the association between plasma miRNAs and risk of VTE in high-grade glioma. Results: We conducted a nested-case control study within 152 patients with WHO grade IV glioma that had been included in the Vienna Cancer and Thrombosis Study (CATS), a prospective cohort study focused on risk factors for VTE in newly diagnosed or recurrent cancer. At study inclusion a single blood draw was taken, and patients were thereafter followed for a maximum of two years. During that time, 24 patients (16%) developed VTE. Of the other 128 patients, we randomly selected 24 age- and sex-matched controls. After sample quality control, the final group size was 21 VTE-patients and 23 without VTE. Small RNA next-generation sequencing of plasma was performed. We observed that hsa-miR-451a was globally the most abundant miRNA. Notably, 51% of all miRNAs showed a correlation with platelet count. The analysis of miRNAs differentially regulated in VTE patients – with and without platelet adjustment – identified potential VTE biomarker candidates such as has-miR- 221-3p. Conclusion: We here provide one of the largest and deepest peripheral blood miRNA datasets of high-grade glioma patients so far. Further, we confirm previous observations of a considerable impact of platelet count on the blood miRNome. And, finally, we present first VTE biomarker candidates that can serve as the starting point for future confirmatory research. Overall design: miRNA sequencing of a nested case-control cohort