Assessment of glutathione-S-transferase and glutathione reductase in patients with squamous-cell carcinoma of buccal mucosa.
Serum and tumor cytosolic levels of glutathione-S-transferase (GST) and glutathione-reductase (GR) activity were determined spectrophotometrically. The levels were correlated with clinicopathological criteria and a tobacco-associated protein band (T band) found in serum. The results showed significantly decreased mean serum GST levels (p < 0.02) in cancer patients as compared with controls. However, mean serum GR levels were significantly higher in patients than in controls (p < 0.01). T-band-positive patients showed low GST and low GR activity as compared with T-band-negative patients. Tumor cytosolic-enzyme levels of GST and GR activity were significantly higher (p < 0.0003 and p < 0.0001, respectively) than in corresponding adjacent noncancerous mucosa. Tumour cytosolic GST and GR activity showed significant association with clinicopathologic criteria, e.g., stage, histologic grade and nodal involvement. T-band-negative patients showed significantly higher levels of GST (p < 0.0001) than did T-band-positive patients. Low levels of cytosolic GST may be associated with increased susceptibility towards carcinogen-induced damage. The results suggest that the presence of T band in the sera may be associated with a high-risk phenotype due to decreased detoxification ability.
Rawal
R M
RM
Department of Cancer Biology, Gujarat Cancer and Research Institute, Ahmedabad, India.
Patel
D D
DD
Patel
B P
BP
Patel
M M
MM
Wadhwa
M K
MK
Patel
P S
PS
Bhatavdekar
J M
JM
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000201:enzymology* / Q000473:pathology; D003600:Cytosol / Q000201:enzymology; D005980:Glutathione Reductase / Q000097:blood / Q000378:metabolism*; D005982:Glutathione Transferase / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000166:cytology / Q000201:enzymology* / Q000473:pathology; D009062:Mouth Neoplasms / Q000097:blood / Q000201:enzymology* / Q000473:pathology; D009367:Neoplasm Staging; D012016:Reference Values; D012907:Smoking
D005980:Glutathione Reductase; D005982:Glutathione Transferase