| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2774982 | Experimental and Molecular Pathology | 2016 | 5 Pages |
•The level of GA mRNAs in G1 + G2 grade GEP-NETs was tested for the first time.•KGA was overexpressed, while GAC remained unaltered in tumor samples.•The lowered GAC/KGA ratio bespeaks the slowly proliferative phenotype.•The expression of the GLS2 gene tended to be elevated in GEP-NETs.
Glutamine (Gln) is a crucial metabolite in cancer cells of different origin, and the expression and activity of different isoforms of the Gln-degrading enzyme, glutaminase (GA), have variable implications for tumor growth and metabolism. Human glutaminases are encoded by two genes: the GLS gene encodes the kidney-type glutaminases, KGA and GAC, while the GLS2 gene encodes the liver-type glutaminases, GAB and LGA. Recent studies suggest that the GAC isoform and thus high GAC/KGA ratio, are characteristic of highly proliferating tumors, while GLS2 proteins have an inhibitory effect on tumor growth. Here we analyzed the expression levels of distinct GA transcripts in 7 gastroenteropancreatic neuroendocrine tumors (GEP-NETs) with low proliferation index and 7 non-neoplastic tissues. GEP-NETs overexpressed KGA, while GAC, which was the most abundant isoform, was not different from control. The expression of the GLS2 gene showed tendency towards elevation in GEP-NETs compared to control. Collectively, the expression pattern of GA isoforms conforms to the low proliferative capacity of GEP-NETs encompassed in this study.
