Lack of expression of the liver-type glutaminase (LGA) mRNA in human malignant gliomas.
In the central nervous system (CNS), liver-type glutaminase (LGA) shows a unique nuclear localization suggesting its role in the regulation of transcription rather than in the cellular glutamine metabolism. RT-PCR analysis of RNA derived from postoperative tissue samples revealed the absence or only traces of LGA mRNA in all (9) cases of malignant gliomas (astrocytoma anaplasticum, AA, WHO grade III; glioblastoma multiforme, WHO grade IV) examined. The RNA was strongly expressed in the non-neoplastic tissue derived from the same patients (6 cases), and in most of the brain metastases from different organs (5 out of 7 cases). By contrast, the mRNAs coding for the kidney-type glutaminase (KGA) and its less ubiquitous isoform GAC, which catalyze degradation of the cytoplasmic pool of Gln, were expressed in all the tissues examined. The lack of LGA may be thus considered as a useful negative diagnostic marker of highly malignant gliomas in situ.
Szeliga
Monika
M
Department of Neurotoxicology, Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Pawińskiego 5, Poland.
Sidoryk
Marta
M
Matyja
Ewa
E
Kowalczyk
Paweł
P
Albrecht
Jan
J
D015152:Blotting, Northern / Q000379:methods; D015139:Blotting, Southern / Q000379:methods; D018076:DNA, Complementary / Q000032:analysis; D005910:Glioma / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D005972:Glutaminase / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D018709:Statistics, Nonparametric
D018076:DNA, Complementary; D012333:RNA, Messenger; D005972:Glutaminase