p53R2, p53 inducible ribonucleotide reductase gene, correlated with tumor progression of non-small cell lung cancer

p53R2 plays a crucial role in supplying dNTPs for DNA repair. The expression of p53R2 is induced by DNA- damaging agents in a p53-dependent manner and p53R2 translocates to the nucleus upon DNA damage. Immunohistochemistry was used to analyze the protein expression of p53R2 in paraffin-embedded tumor samples from 130 well-characterized non-small cell lung cancer (NSCLC) patients and the expression level of p53R2, clinical variables and survival outcome were compared. A positive expression of p53R2 was detected in the cytoplasm of tumor cells in 61 of the 130 patients (46.2%) with NSCLC. The positive ratio was significantly higher in the patients with pathological stage II/III, pathological T3-4 and pathological N1-3 than in those with stage I, T1-2 and N0, respectively. No significant difference was observed between the p53R2 expression and the gender, age at operation, histological type or p53 expression. Though our findings do not support that the p53R2 immunocytochemical marker alone plays an important prognostic role in NSCLC, the DNA repair pathway mediated by p53R2 may be responsible for controlling the growth of lung cancer. Lung cancer is the leading cause of cancer-related death in the world. Despite years of multidisciplinary management and research, the prognosis for patients with lung cancer remains dismal, with a 5-year survival rate of only 14% (1).