SAGE mRNA expression in advanced-stage lung cancers

Aims: SAGE and HAGE are recently isolated genes, which were thought to be expressed tumour-specifically, and are potentially coding for tumour-specific antigens recognized by T lymphocytes. The expression of these genes may serve as a useful diagnostic marker in detecting malignant disease. We report the correlation of SAGE and HAGE expression with clinicopathological features in patients with lung cancer who had undergone surgery. Methods: Expression of SAGE and HAGE messenger RNA was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) in 102 lung carcinomas and adjacent histological normal lung samples using LightCycler. Results: SAGE/GAPDH mRNA expression was not significantly different between the tumour of lung cancer tissue (3.777±10.802) and normal lung tissue (3.028±3.356, p=0.7283). There was no relationship between SAGE gene expression and age, gender or N-status. SAGE/GAPDH expression was significantly higher in stage III–IV lung cancer (6.180±16.475) than in stage I lung cancer (1.534±2.591, p=0.0393). SAGE/GAPDH expression was also significantly higher in T4 lung cancer (9.183±23.117) than in T2 lung cancer (2.676±5.943, p=0.0362) and T1 lung cancer (2.373±3.433, p=0.0371). Conclusions: Detection for SAGE mRNA expression is possible in lung cancer samples. There was no relationship between HAGE gene expression and clinicopathological factor, such that the usefulness of detection for HAGE mRNA expression is limited for lung cancer.