Expression status of ribonucleotide reductase small subunits hRRM2/p53R2 as prognostic biomarkers in stage I and II non-small cell lung cancer

Anticancer Res. 2011 Oct;31(10):3475-81.

Abstract

Overexpression of ribonucleotide reductase M2 (hRRM2) and p53-dependent RR small subunit (p53R2) has been correlated with tumor malignancy and progression in several types of cancer. The aim of this study was to determine the association of p53R2/hRRM2 expression with clinicopathological characteristics of stage I and II non-small cell lung cancer (NSCLC). Immunohistochemistry was conducted on a tissue array that included 92 samples. Correlations between hRRM2 and p53R2 expression and clinicopathological factors, recurrence/metastasis, and outcomes were analyzed. The analyses revealed that there was no correlation between p53R2 expression and clinicopathological factors; hRRM2 was only positively related to poor tumor differentiation (p=0.006). Regarding overall survival during the follow-up period, patients with p53R2+/hRRM2- tumors had the best outcomes (p<0.01). Multivariant Cox analysis revealed that p53R2 (risk=0.232, 95% CI=0.086-0.626, p=0.004) not only served as a prognostic biomarker to predict survival, but also as an independent biomarker to predict disease-free survival (risk=0.545, 95% CI=0.301-0.987, p=0.045) of patients with NSCLC. Therefore, we consider that the expression of p53R2 can be used not only as a biomarker for overall survival, but also as an indicator for tumor recurrence. Based on our finding, p53R2 expression seems more important than that of hRRM2 in prognosis of early-stage lung cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Biomarkers, Tumor / metabolism*
  • Carcinoma, Non-Small-Cell Lung / diagnosis
  • Carcinoma, Non-Small-Cell Lung / enzymology*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Cell Cycle Proteins / metabolism*
  • Disease-Free Survival
  • Female
  • Humans
  • Immunohistochemistry
  • Lung Neoplasms / diagnosis
  • Lung Neoplasms / enzymology*
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Prognosis
  • Proportional Hazards Models
  • Protein Subunits / metabolism*
  • Ribonucleoside Diphosphate Reductase / metabolism*
  • Ribonucleotide Reductases / metabolism*
  • Treatment Outcome

Substances

  • Biomarkers, Tumor
  • Cell Cycle Proteins
  • Protein Subunits
  • RRM2B protein, human
  • Ribonucleotide Reductases
  • ribonucleotide reductase M2
  • Ribonucleoside Diphosphate Reductase