Measurement of glutathione S-transferase and its class-pi in plasma and tissue biopsies obtained after laparoscopy and endoscopy from subjects with esophagus and gastric cancer.
OBJECTIVE
To develop an indirect enzyme-linked immunosorbent assay (ELISA) for measuring class-pi glutathione S-transferase (GST) in plasma, and tissue biopsies obtained from upper gastrointestinal cancer (UGI Ca) patients.


METHODS
GST activity and GST-pi concentration were detected in normal human squamous esophageal epithelium, normal gastric cardia and their corresponding malignant tumor biopsies.


RESULTS
Plasma GST was significantly higher (p < 0.05) in UGI Ca patients as compared to those obtained from normal individuals. Plasma GST-pi concentration in normal subjects was 6.6 +/- 1.9 ng/mg protein, whereas it was higher in UGI Ca patients (esophageal, 10.0 +/- 1.8; gastric, 10.7 +/- 1.7 ng/mL, p <or= 0.01). GST and GST-pi levels were higher in surgically resected tumor biopsies as compared to normal tissues adjacent to a tumor (p < 0.05). GST-pi was also elevated in malignant esophagus and gastric biopsies taken at endoscopy as compared to normal and normal-appearing esophageal tissues (p < 0.05). Total GST was also increased significantly in gastric malignant tissues although its activity was within the same range in normal and normal-appearing tissues. A significant correlation between plasma GST-pi with that in malignant tissues was observed. Total GST and GST-pi were also correlated in different malignant tissues.


CONCLUSIONS
Biopsies obtained at endoscopy can be used satisfactorily to measure tumor markers.
Mohammadzadeh
G S
GS
Department of Biochemistry, Faculty of Medical Sciences, Tarbiat Modarres University, PO Box 14115-111, I R, Tehran, Iran.
Nasseri Moghadam
S
S
Rasaee
M J
MJ
Zaree
A B
AB
Mahmoodzadeh
H
H
Allameh
A
A
D000328:Adult; D000368:Aged; D001706:Biopsy; D004724:Endoscopy; D004797:Enzyme-Linked Immunosorbent Assay; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000201:enzymology; D004947:Esophagus / Q000201:enzymology / Q000473:pathology; D005260:Female; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase / Q000032:analysis / Q000097:blood*; D006801:Humans; D007492:Iran; D007527:Isoenzymes / Q000032:analysis / Q000097:blood*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D013270:Stomach / Q000201:enzymology / Q000473:pathology; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000201:enzymology
D007527:Isoenzymes; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase