Glutathione-S-transferase pi expression and activity is increased in colonic neoplasia.
Glutathione-S-transferase (GST) isoenzymes are involved in the conjugation of glutathione to electrophilic carcinogens. Recent studies have shown increased levels and activities of GST in different tumors suggesting their role in carcinogen detoxification. This study compared GST activity levels and GST-pi protein expression in paired samples of colorectal cancer, adenoma and adjacent normal mucosa from a total of thirteen patients. GST was isolated from human colorectal specimens and assayed spectrophotometrically; Western immunoblot analysis was used to quantify GST-pi levels. GST activity was greater in both colorectal cancer and adenomas than in adjacent normal colonic tissue, although statistical significance was achieved only when comparing colorectal cancer to normal tissue. Based on these observations, we conclude that increased GST activity may be a useful marker of colonic neoplasia.
Baylor-Sammons Cancer Center, Dallas, Texas, USA.
Kamatham A
KA
Naidu
Aejaz
A
Nasir
Haim
H
Pinkas
Hans E
HE
Kaiser
Patric
P
Brady
Domenico
D
Coppola
D000236:Adenoma / Q000201:enzymology* / Q000473:pathology; D014408:Biomarkers, Tumor; D015153:Blotting, Western; D002277:Carcinoma / Q000201:enzymology* / Q000473:pathology; D003110:Colonic Neoplasms / Q000201:enzymology*; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000201:enzymology / Q000473:pathology; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male
D014408:Biomarkers, Tumor; D007527:Isoenzymes; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase