Immunohistochemical localization of glutathione s-transferase isoenzymes (gsta, Gstp, Gstm4, And Gstt1) and tumour marker p53 in matched tissue from normal larynx and laryngeal carcinoma: correlations with prognostic factors.
OBJECTIVE
The immunohistochemical staining characteristics of glutathione S-transferase (GST) alpha (GSTA), pi (GSTP), mu (GSTM4), and theta (GSTT1) and P53 were investigated in laryngeal squamous cell carcinoma (LSCC) cases and normal laryngeal tissue from 46 patients. The relationships between expression of the GST isoenzymes and some clinicopathologic features were also examined.


METHODS
For immunohistochemical studies, tissues from 46 patients with LSCC at the Dr. Lütfi Kirdar Kartal Education and Research Hospital were used. The relationship between expression of the GST isoenzymes and P53 in normal and tumour tissue was analyzed using the Wilcoxon signed rank test. The correlation between GST isoenzymes and P53 and clinicopathologic data was also examined using the Spearman rank test.


RESULTS
When the normal and tumour tissues of these cases were compared according to their staining intensity and percentage of positive staining, GSTA expression in normal cells was significantly higher than in tumour cells, and GSTP and P53 expression was higher in tumour cells (p < .05). GSTM and GSTT1 expression was higher in normal cells; however, the statistical significance was low (p > .05). There was no correlation between P53 and GST expression in patients with LSCC. When the immunohistochemical results of GST isoenzymes and P53 were correlated with the clinical parameters, GSTA expression was increased in poorly differentiated laryngeal tumour, but GSTM4 and GSTT1 expression was decreased (p < .05).


CONCLUSIONS
According to these results, GST-A, -P, and T1 and P53 were important in the diagnosis of LSCC.
Sedat
Aydin
A
Department ofOtolaryngology, Head and Neck Surgery, Gu¨lhane Military MedicalAcademy, Ankara, Turkey. sedataydin63@yahoo.com
Serpil
Oguztuzun
O
Nurdan
Gurbuz
G
Aylin
Gul
G
Arif
Sanli
S
Muzeyyen
Ozhavzali
O
Bulent
Satar
S
Sezen
Ozan
O
Nimet
Karadayi
K
D051549:Glutathione S-Transferase pi / Q000096:biosynthesis; D005982:Glutathione Transferase / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D007822:Laryngeal Neoplasms / Q000378:metabolism* / Q000473:pathology; D007830:Larynx / Q000166:cytology / Q000378:metabolism*; D011379:Prognosis; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
D016159:Tumor Suppressor Protein p53; C413545:glutathione S-transferase T1; C484555:GSTA1 protein, human; C514654:GSTM4 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase