Negative hMSH2 Protein Expression in Pancreatic Carcinoma May Predict a Better Prognosis of Patients

Oncol Rep. Jul-Aug 2003;10(4):997-1000.

Abstract

The prognostic values of immunohistochemical staining for hMSH2 and hMLH1 in patients with pancreatic carcinomas were investigated. Fifty-five patients with histologically proven pancreatic carcinomas were studied. Immunohistochemical staining for hMSH2 and hMLH1 was performed by avidin-biotin-peroxidase complex method with a catalyzed signal amplification system. Tumor cells that exhibited an absence of nuclear staining in the presence of non-neoplastic cells with nuclear staining were considered to have an abnormal pattern. Four tumors (7.3%) demonstrated abnormal hMS2-negative staining. One tumor (1.8%) had abnormal hMLH1-negative staining and this tumor showed negative hMSH2 staining. No particular clinicopathologic factor such as tumor location, histology, T-factor, N-factor and TNM-stage were observed in patients with negative hMSH2 staining tumors. Median survival time (MST) of patients with hMSH2-negative tumors was comparatively longer than that of patients with hMSH2-positive tumors, however, there was no significant difference between MSTs of the two groups (56 months vs. 14 months; p=0.16). We concluded that negative hMSH2 immunohistochemical staining in the pancreatic carcinomas may demonstrate certain patients, but not all, who had microsatellite instability-positive tumors. The patients with hMSH2-negative tumors may have better prognoses than those with hMSH2-positive tumors. To clarify these findings, further large number of pancreatic carcinomas must be investigated.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Adult
  • Aged
  • Biomarkers, Tumor / metabolism*
  • Carrier Proteins
  • Cell Differentiation
  • DNA Repair
  • DNA-Binding Proteins / metabolism
  • Down-Regulation
  • Female
  • Humans
  • Immunoenzyme Techniques
  • Male
  • Middle Aged
  • MutL Protein Homolog 1
  • MutS Homolog 2 Protein
  • Neoplasm Proteins / metabolism*
  • Nuclear Proteins
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology
  • Prognosis
  • Proto-Oncogene Proteins / metabolism*
  • Survival Rate

Substances

  • Adaptor Proteins, Signal Transducing
  • Biomarkers, Tumor
  • Carrier Proteins
  • DNA-Binding Proteins
  • MLH1 protein, human
  • Neoplasm Proteins
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • MSH2 protein, human
  • MutL Protein Homolog 1
  • MutS Homolog 2 Protein