Title:The Expression of Glutaminases and their Association with Clinicopathological
Parameters in the Head and Neck Cancers
Volume: 22
Issue: 2
Author(s): Haneen A. Basheer*, Lina Elsalem, Anwar Salem, Artysha Tailor, Keith Hunter and Kamyar Afarinkia
Affiliation:
- Faculty of Pharmacy, Zarqa University, Zarqa 13132, Jordan
Keywords:
Glutaminases, GLS1, GLS2, CD147, immunohistochemistry, head and neck cancers.
Abstract:
Background: The increased glutamine metabolism is a characteristic feature of cancer
cells. The interconversion between glutamine and glutamate is catalyzed by two glutaminase isoforms,
GLS1 and GLS2, which appear to have different roles in different types of cancer. We investigated
for the first time the protein expression of GLS1 and GLS2, and their correlation with advanced
clinicopathological parameters in head and neck cancers.
Methods: Consecutive slides from a tissue microarray comprised of 80 samples ranging from normal
to metastatic were stained immunohistochemically for GLS1, GLS2, HIF-1α or CD147. Following
analysis by two expert pathologists, we carried out a statistical analysis of the scores.
Results: GLS1 and GLS2 were found to be upregulated at the protein level in head and neck tumours
compared to normal tissues, and this increased expression correlated positively (GLS1) and
negatively (GLS2) with tumor grade, indicating a shift of expression between GLS enzyme isoforms
based on tumor differentiation. Increased expression of GLS1 was associated with high
CD147 expression, and elevated GLS2 expression was associated with both high CD147 and high
HIF-1α expressions. The correlation of the GLS1 and GLS2 with HIF-1α or CD147 was strongly
associated with more advanced clinicopathological parameters.
Conclusion: The increased expression of GLS1 and GLS2 may be explored as a new treatment for
head and neck cancers.