p53AIP1 Expression can be a Prognostic Marker in Non-small Cell Lung Cancer

p53AIP1 is a potential mediator of p53-dependent apoptosis that is mutated in many kinds of carcinoma. To investigate the role of this gene for non-small cell lung cancer, we compared the relationship between p53AIP1 gene expression and clinicopathological status of lung cancer. Seventy samples from non-small cell lung cancer patients were obtained between 1997 and 2003. For quantitative evaluation of RNA expression by polymerase chain reaction (PCR) we used the Taqman PCR methods. Exons 5–8 of the p53 gene were analysed using PCR–single-stranded conformation polymorphism and sequenced for mutation analysis. p53AIP1 gene expression levels in the lymph node metastasis-positive group were significantly lower than in the negative group (positive 35.1 ± 83.9; negative 64.2 ± 113.4; P = 0.0486). The overall survival of the p53AIP1 low expression group was significantly worse than that of the p53AIP1 high expression group ( P = 0.0206). In the multivariate Cox proportional hazard model, p53AIP1 ( P = 0.0489) was the independent predictor for overall survival. When we investigated mutation analyses of the p53 gene, we could find several point mutations in 15.7% of all samples. However, there was no relationship between p53AIP1 expression and p53 status. These data suggest that the p53AIP1 gene is important for non-small cell lung cancer progression and may be a possible prognostic marker.