Exfoliated buccal and microdissected lung cell expression of antioxidant enzymes.
BACKGROUND
An exfoliated buccal cell biomarker assay for antioxidant gene transcript levels was used to measure inter-tissue concordance with lung, and inter-subject variability in a lung cancer case-control study.


METHODS
First, qualitative RNA-specific RT-PCR was used to compare expression in exfoliated buccal cells with that in laser microdissected lung tissue remote from the tumor from 14 individuals providing both specimens.


RESULTS
There was complete [100% for quinone oxidoreductase 1 (NQO1), glutathione peroxidase (GPX), and superoxide dismutase 1 (SOD1)], or predominant [85.7% for catalase (CAT)] inter-tissue concordance for qualitative expression. Second, quantitative real-time RT-PCR for antioxidant enzyme transcript levels was performed in exfoliated buccal samples from these same 14 individuals, as well as 28 additional individuals providing buccal cells only, for a total of 42 buccal specimens (19 current smokers and 23 ex- or never-smokers), of whom 26 (61.39%) had a new diagnosis of lung cancer.


CONCLUSIONS
Wide inter-individual expression differences for each gene transcript (>10(1)-10(4)-fold) were observed in the exfoliated buccal cells, unrelated to smoking and case-control status. In multivariate analyses, family history of tobacco-related malignancy correlated inversely with buccal NQO1 and CAT mRNA levels (p=0.003, p<0.001, respectively). This antioxidant expression trait may relate to family risk of cancer, but is notably unrelated to oxidant challenges inherent in cigarette smoke.
Kumar
Shalini V
SV
Laboratory of Human Toxicology and Molecular Epidemiology, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509, USA.
Jain
Ritu
R
Mokhiber
Katherine
K
Venezia
Ann
A
Sheehan
Angela
A
Spivack
Simon D
SD
D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000096:biosynthesis; D002610:Cheek / Q000502:physiology; D015870:Gene Expression; D005979:Glutathione Peroxidase / Q000096:biosynthesis; D006801:Humans; D007834:Lasers; D008168:Lung / Q000166:cytology / Q000201:enzymology*; D008175:Lung Neoplasms / Q000201:enzymology / Q000209:etiology; D008297:Male; D042282:Microdissection; D009061:Mouth Mucosa / Q000166:cytology / Q000201:enzymology*; D011808:Quinone Reductases / Q000096:biosynthesis; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012907:Smoking / Q000009:adverse effects; D013482:Superoxide Dismutase / Q000096:biosynthesis; D000072105:Superoxide Dismutase-1
D000975:Antioxidants; C000606290:SOD1 protein, human; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; D011808:Quinone Reductases