SDPS-13 CELL LINE STUDY OF NUCLEOSOME-BASED BIOMARKERS IN THE DIAGNOSIS AND DETECTION OF RELAPSES IN GLIOBLASTOMA

Abstract Currently, glioblastoma (GBM) diagnosis and monitoring rely on neuroimaging and histopathological confirmation. However, overall survival has not improved in last decades due to therapeutic failure and to a lack of biomarkers for relapses’ detection. Liquid biopsies (i.e. blood or cerebrospinal fluid) using nucleosomes-containing-histone post-translational modifications (PTMs) have the potential to become valuable biomarkers for diagnosis and monitoring GBM. Four glioblastoma cell lines (SF-126, U-87MG, U-118MG, and U-138MG) compared to a healthy microglia cell line (HMC3) and other solid cancer cell lines including pancreas (MIA PaCa-2), liver (HepG2), and cervix/uterus (HeLa) have been analyzed to identify their epigenetic profile. Nucleosomes were extracted and analyzed with the Nu.Q® Discover immunoassays platform (Belgian Volition) addressing 13 histone-PTMs. Quantitative results of PTMs expression were normalized on quantification of total nucleosomes (H3.1-nucleosomes). The immunoassay identified three candidate biomarkers compared to control cell lines (n=4): citrullinated-histone H3 (H3R8Cit) (control=4.68% ; GBM=13.88% ; p