MCM2 is an independent predictor of survival in patients with non-small-cell lung cancer

J Clin Oncol. 2001 Nov 15;19(22):4259-66. doi: 10.1200/JCO.2001.19.22.4259.

Abstract

Purpose: Minichromosome maintenance protein 2 (MCM2) is a component of the prereplicative complex. It is essential for eukaryotic DNA replication and is only expressed in proliferating cells. The prognostic utility of MCM2 compared with Ki-67, another marker of proliferating cells, on survival of patients with non-small-cell lung cancer (NSCLC) was studied.

Patients and methods: We examined the immunohistochemical expression of MCM2 and Ki-67 in primary pathologic tumor specimens from 221 NSCLC patients. For each marker, the fraction of tumor cells with positive staining was assessed as a percentage and categorized into four groups: 0% to 24%, 25% to 49%, 50% to 74%, and > or = 75%. MCM2 and Ki-67 immunoreactivities were compared with each other, and associations with pathologic and clinical parameters predictive of survival were analyzed with the chi(2) test. Cox regression models were used to assess associations between MCM2 and Ki-67 and survival while controlling for confounders.

Results: Independent variables significantly associated with survival were tumor stage, performance status, and staining category. Patients with less than 25% MCM2 immunoreactivity had a longer median survival time than patients with > or = 25% MCM2 immunoreactivity (46 v 31 months; P =.039) and a lower relative risk (RR) of death (RR, 0.55, 95% confidence interval, 0.34 to 0.88). There was no significant association between survival and Ki-67 expression.

Conclusion: Immunostaining of tumor cells for MCM2 is an independent prognostic parameter of survival for patients with NSCLC. Interpretable results can be obtained on more than 96% of paraffin-embedded specimens, and approximately 35% will be in the favorable subgroup, with less than 25% positively stained tumor cells. Whether MCM2 is predictive of response to therapy needs to be studied.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenocarcinoma / chemistry
  • Adenocarcinoma / mortality
  • Adenocarcinoma / pathology
  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Adenosquamous / chemistry
  • Carcinoma, Adenosquamous / mortality
  • Carcinoma, Adenosquamous / pathology
  • Carcinoma, Large Cell / chemistry
  • Carcinoma, Large Cell / mortality
  • Carcinoma, Large Cell / pathology
  • Carcinoma, Non-Small-Cell Lung / chemistry
  • Carcinoma, Non-Small-Cell Lung / mortality*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Carcinoma, Squamous Cell / chemistry
  • Carcinoma, Squamous Cell / mortality
  • Carcinoma, Squamous Cell / pathology
  • Cell Count
  • Female
  • Humans
  • Immunoenzyme Techniques
  • Ki-67 Antigen / analysis
  • Lung Neoplasms / chemistry
  • Lung Neoplasms / mortality*
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Minichromosome Maintenance Complex Component 2
  • Neoplasm Staging
  • Nuclear Proteins / analysis*
  • Prognosis
  • Survival Rate

Substances

  • Ki-67 Antigen
  • Nuclear Proteins
  • Minichromosome Maintenance Complex Component 2