Creation of a plasma collection for the search of diagnostic biomarkers of glial tumors

Aim . To create a collection of plasma samples of patients with brain tumors (BTs) for the development of a diagnostic microRNA (ribonucleic acid) panel of glial tumors. Material and methods . Plasma samples of patients with benign and malignant BTs were obtained by double centrifugation of whole blood and then frozen at -75оС.Fifty-nine RNA samples isolated from blood plasma were analyzed by next-generation sequencing (NGS). Results . Currently, the biobank contains samples from 339 patients with primary and secondary BTs and 10 control group individuals (698 samples — 2 plasma aliquots per individual), including 143 men and 206 women. The age of the patients ranged from 19 to 91 years (median — 56 years). Primary BTs (41%) included two following groups: benign (33,7%) and malignant (66,3%). Meningiomas constituted the bulk (91%) of the benign BTs. Among the malignant tumors, glioblastomas (46,7%) and astrocytomas (41,6%) prevailed, while oligodendrogliomas and ependymomas accounted for only 9,1 and 2,5%, respectively. Secondary BTs (59%) are represented by recurrent glial tumors (92,5%) and metastatic tumors (7,5%) of lung cancer (71,4%) and breast cancer (28.6%). A protocol for the primary preparation of liquid biopsy samples was implemented, which made it possible to obtain high-quality deoxyribonucleic acid libraries for the selected microRNA profiling platform. Conclusion . The creation of a plasma sample collection is the basis for searching circulating biomarkers of BTs.