Meta-analysis and experimental validation identified FREM2 and SPRY1 as new glioblastoma marker candidates

Vidak, Marko (author), Jovchevska, Ivana (author), Šamec, Neja (author), Zottel, Alja (author), Liović, Mirjana (author), Rozman, Damjana (author), Džeroski, Sašo (author), Juvan, Peter (author), Komel, Radovan (author)

Glioblastoma (GB) is the most aggressive brain malignancy. Although some potential glioblastoma biomarkers have already been identified, there is a lack of cell membrane-bound biomarkers capable of distinguishing brain tissue from glioblastoma and/or glioblastoma stem cells (GSC), which are responsible for the rapid post-operative tumor reoccurrence. In order to find new GB/GSC marker candidates that would be cell surface proteins (CSP), we have performed meta-analysis of genome-scale mRNA expression data from three data repositories (GEO, ArrayExpress and GLIOMASdb). The search yielded ten appropriate datasets, and three (GSE4290/GDS1962, GSE23806/GDS3885, and GLIOMASdb) were used for selection of new GB/GSC marker candidates, while the other seven (GSE4412/GDS1975, GSE4412/GDS1976, E-GEOD-52009, E-GEOD-68848, E-GEOD-16011, E-GEOD-4536, and E-GEOD-74571) were used for bioinformatic validation. The selection identified four new CSP-encoding candidate genes-CD276, FREM2, SPRY1, and SLC47A1-and the bioinformatic validation confirmed these findings. A review of the literature revealed that CD276 is not a novel candidate, while SLC47A1 had lower validation test scores than the other new candidates and was therefore not considered for experimental validation. This validation revealed that the expression of FREM2-but not SPRY1-is higher in glioblastoma cell lines when compared to non-malignant astrocytes. In addition, FREM2 gene and protein expression levels are higher in GB stem-like cell lines than in conventional glioblastoma cell lines. FREM2 is thus proposed as a novel GB biomarker and a putative biomarker of glioblastoma stem cells. Both FREM2 and SPRY1 are expressed on the surface of the GB cells, while SPRY1 alone was found overexpressed in the cytosol of non-malignant astrocytes.

• Language: English
• Keywords: glioblastoma, glioblastoma stem cells, biomarkers, data repositories, meta-analysis, cell surface, experimental validation, FREM2, SPRY1
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2018
• Number of pages: 24 str.
• Numbering: Vol. 19, iss. 5, art. 1369
• PID: 20.500.12556/RUL-131851
• UDC: 577
• ISSN on article: 1422-0067
• DOI: 10.3390/ijms19051369
• COBISS.SI-ID: 33752793
• Publication date in RUL: 04.10.2021

Record is a part of a journal

• Title: International journal of molecular sciences
• Shortened title: Int. j. mol. sci.
• Publisher: MDPI
• ISSN: 1422-0067
• COBISS.SI-ID: 2779162

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 04.05.2018

Secondary language

• Language: Slovenian
• Keywords: glioblastom, matične celice glioblastoma, biomarkerji