P53R2 expression as a prognostic biomarker in early stage non-small cell lung cancer

p53R2 is a small subunit of ribonucleotide reductase (RR) which has 80% homology to hRRM2 and metastasis suppressing potential. Previous reports suggested that the expression of p53R2 is used as a prognostic factor and chemo-therapy response indicator in several types of cancer. This study aimed to elucidate the association of p53R2 expression and the clinicopathological characteristics of early stage non small cell lung cancer (NSCLC). Immuno histochemistry was conducted on a tissue array including 92 early stage NSCLC samples. Correlations between p53R2 and clinicopathological factors, recurrence/metastasis and outcomes were analyzed. The analyses showed that there was no correlation between p53R2 expression and the clinicopathological factors. Among disease-free patients during follow-up, patients with p53R2(+) had a better outcome than those with p53R2(-) (P=0.022). By using Cox multivariate regression analysis, p53R2 (risk factor 3.801; 95% CI 1.004-9.454; P=0.044) served as a prognostic biomarker in the prediction of the survival rate for NSCLC patients. Detection of the RR subunit p53R2 may therefore be a useful prognostic marker in early stage NSCLC.