Loss of 5'-Methylthioadenosine Phosphorylase (MTAP) is Frequent in High-Grade Gliomas; Nevertheless, it is Not Associated with Higher Tumor Aggressiveness

The 5'-methylthioadenosine phosphorylase (MTAP) gene is located in the chromosomal region 9p21. MTAP deletion is a frequent event in a wide variety of human cancers; however, its biological role in tumorigenesis remains unclear. The purpose of this study was to characterize the MTAP expression profile in a series of gliomas and to associate it with patients' clinicopathological features. Moreover, we sought to evaluate, through glioma gene-edited cell lines, the biological impact of MTAP in gliomas. MTAP expression was evaluated in 507 glioma patients by immunohistochemistry (IHC), and the expression levels were associated with patients' clinicopathological features. Furthermore, an in silico study was undertaken using genomic databases totalizing 350 samples. In glioma cell lines, MTAP was edited, and following MTAP overexpression and knockout (KO), a transcriptome analysis was performed by NanoString Pan-Cancer Pathways panel. Moreover, MTAP's role in glioma cell proliferation, migration, and invasion was evaluated. Homozygous deletion of 9p21 locus was associated with a reduction of MTAP mRNA expression in the TCGA (The Cancer Genome Atlas) - glioblastoma dataset (p < 0.01). In addition, the loss of MTAP expression was markedly high in high-grade gliomas (46.6% of cases) determined by IHC and Western blotting (40% of evaluated cell lines). Reduced MTAP expression was associated with a better prognostic in the adult glioblastoma dataset (p < 0.001). Nine genes associated with five pathways were differentially expressed in MTAP-knockout (KO) cells, with six upregulated and three downregulated in MTAP. Analysis of cell proliferation, migration, and invasion did not show any significant differences between MTAP gene-edited and control cells. Our results integrating data from patients as well as in silico and in vitro models provide evidence towards the lack of strong biological importance of MTAP in gliomas. Despite the frequent loss of MTAP, it seems not to have a clinical impact in survival and does not act as a canonic tumor suppressor gene in gliomas.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:9

Enthalten in:

Cells - 9(2020), 2 vom: 20. Feb.

Sprache:

Englisch

Beteiligte Personen:

Menezes, Weder Pereira de [VerfasserIn]
Silva, Viviane Aline Oliveira [VerfasserIn]
Gomes, Izabela Natália Faria [VerfasserIn]
Rosa, Marcela Nunes [VerfasserIn]
Spina, Maria Luisa Corcoll [VerfasserIn]
Carloni, Adriana Cruvinel [VerfasserIn]
Alves, Ana Laura Vieira [VerfasserIn]
Melendez, Matias [VerfasserIn]
Almeida, Gisele Caravina [VerfasserIn]
Silva, Luciane Sussuchi da [VerfasserIn]
Clara, Carlos [VerfasserIn]
da Cunha, Isabela Werneck [VerfasserIn]
Hajj, Glaucia Noeli Maroso [VerfasserIn]
Jones, Chris [VerfasserIn]
Bidinotto, Lucas Tadeu [VerfasserIn]
Reis, Rui Manuel [VerfasserIn]

Links:

Volltext

Themen:

5'-methylthioadenosine phosphorylase
5’-methylthioadenosine phosphorylase (MTAP)
EC 2.4.2.1
EC 2.4.2.28
Glioblastoma
Glioma
Immunohistochemistry
Invasion
Journal Article
Migration
Proliferation
Purine-Nucleoside Phosphorylase
Research Support, Non-U.S. Gov't
Tumor biology

Anmerkungen:

Date Completed 19.02.2021

Date Revised 19.02.2021

published: Electronic

Citation Status MEDLINE

doi:

10.3390/cells9020492

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM306860228