MicroRNA-181a as novel liquid biopsy marker of central nervous system involvement in pediatric acute lymphoblastic leukemia

Bálint Egyed; Nóra Kutszegi; Judit C Sági; András Gézsi; Andrea Rzepiel; Tamás Visnovitz; Péter Lőrincz; Judit Müller; Marianna Zombori; Csaba Szalai; Dániel J Erdélyi; Gábor T Kovács; Ágnes F Semsei

doi:10.1186/s12967-020-02415-8

MicroRNA-181a as novel liquid biopsy marker of central nervous system involvement in pediatric acute lymphoblastic leukemia

J Transl Med. 2020 Jun 22;18(1):250. doi: 10.1186/s12967-020-02415-8.

Authors

Bálint Egyed^{1

2}, Nóra Kutszegi¹, Judit C Sági², András Gézsi^{3

4}, Andrea Rzepiel¹, Tamás Visnovitz², Péter Lőrincz⁵, Judit Müller¹, Marianna Zombori⁶, Csaba Szalai^{2

6}, Dániel J Erdélyi¹, Gábor T Kovács¹, Ágnes F Semsei⁷

Affiliations

¹ 2nd Department of Pediatrics, Semmelweis University, 7-9 Tűzoltó Str, Budapest, 1094, Hungary.
² Department of Genetics, Cell- and Immunobiology, Semmelweis University, 4 Nagyvárad Sqr, Budapest, 1089, Hungary.
³ MTA-SE Immune-Proteogenomics Extracellular Vesicle Research Group, Semmelweis University, 4 Nagyvárad Sqr, Budapest, 1089, Hungary.
⁴ Department of Measurements and Information Systems, Budapest University of Technology and Economics, 2 Magyar tudosok korutja, Budapest, 1117, Hungary.
⁵ Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, 1/c Pázmány Promenade, Budapest, 1117, Hungary.
⁶ Heim Pal National Pediatric Institute, 86 Üllői Str, Budapest, 1089, Hungary.
⁷ Department of Genetics, Cell- and Immunobiology, Semmelweis University, 4 Nagyvárad Sqr, Budapest, 1089, Hungary. semsei.agnes@med.semmelweis-univ.hu.

Abstract

Background: Refractory central nervous system (CNS) involvement is among the major causes of therapy failure in childhood acute leukemia. Applying contemporary diagnostic methods, CNS disease is often underdiagnosed. To explore more sensitive and less invasive CNS status indicators, we examined microRNA (miR) expressions and extracellular vesicle (EV) characteristics.

Methods: In an acute lymphoblastic leukemia (ALL) discovery cohort, 47 miRs were screened using Custom TaqMan Advanced Low-Density Array gene expression cards. As a validation step, a candidate miR family was further scrutinized with TaqMan Advanced miRNA Assays on serial cerebrospinal fluid (CSF), bone marrow (BM) and peripheral blood samples with different acute leukemia subtypes. Furthermore, small EV-rich fractions were isolated from CSF and the samples were processed for immunoelectron microscopy with anti-CD63 and anti-CD81 antibodies, simultaneously.

Results: Regarding the discovery study, principal component analysis identified the role of miR-181-family (miR-181a-5p, miR-181b-5p, miR-181c-5p) in clustering CNS-positive (CNS⁺) and CNS-negative (CNS^‒) CSF samples. We were able to validate miR-181a expression differences: it was about 52 times higher in CSF samples of CNS⁺ ALL patients compared to CNS^‒ cases (n = 8 vs. n = 10, ΔFC = 52.30, p = 1.5E-4), and CNS⁺ precursor B cell subgroup also had ninefold higher miR-181a levels in their BM (p = 0.04). The sensitivity of CSF miR-181a measurement in ALL highly exceeded those of conventional cytospin in the initial diagnosis of CNS leukemia (90% vs. 54.5%). Pellet resulting from ultracentrifugation of CNS⁺ CSF samples of ALL patients showed atypical CD63^-/CD81^- small EVs in high density by immunoelectron microscopy.

Conclusions: After validating in extensive cohorts, quantification of miR-181a or a specific EV subtype might provide novel tools to monitor CNS disease course and further adjust CNS-directed therapy in pediatric ALL.

Keywords: Central nervous system involvement; Liquid biopsy; Pediatric leukemia; Small extracellular vesicles; microRNA-based biomarker.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biomarkers
Central Nervous System
Child
Humans
Liquid Biopsy
MicroRNAs* / genetics
Precursor Cell Lymphoblastic Leukemia-Lymphoma* / genetics

Substances

Biomarkers
MIrn181 microRNA, human
MicroRNAs