Overexpression of manganese superoxide dismutase mRNA may correlate with aggressiveness in gastric and colorectal adenocarcinomas

Int J Oncol. 2000 Jul;17(1):107-12. doi: 10.3892/ijo.17.1.107.


The expression or activity of manganese superoxide dismutase (Mn-SOD) is reduced in a variety of malignant tumors and Mn-SOD may act as a new type of tumor suppressor gene. On the other hand, increased expression of Mn-SOD can diminish the cytotoxic effects of several anticancer modalities, including tumor necrosis factor alpha, ionizing radiation, certain chemotherapeutic agents and hyperthermia. Although Mn-SOD expression and its role in various cancers are intensely studied, little is known about its function in gastrointestinal carcinomas. To examine the expression level and significance of Mn-SOD in gastrointestinal carcinomas, Mn-SOD mRNA expression was examined in 53 gastric carcinoma and 38 colorectal carcinoma by reverse transcription-polymerase chain reaction and was compared with those in the corresponding normal mucosal tissues. The tumor/normal (T/N) ratio was calculated and the data were clinicopathologically analyzed. The average T/N ratios of Mn-SOD mRNA expression in gastric and colorectal carcinomas were 2.19 and 3. 72, respectively. Clinicopathologic analyses revealed positive correlation between the Mn-SOD expression level and venous invasion in both gastric and colorectal carcinomas (p<0.05 and p<0.05, respectively). Furthermore, the colorectal carcinoma with lymph node metastasis showed significantly higher Mn-SOD expression than those without it (p<0.05). Our results suggest that Mn-SOD mRNA overexpression can occur in gastric and colorectal carcinomas and may be related to increased aggressiveness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / enzymology
  • Adenocarcinoma / genetics
  • Adenocarcinoma / pathology*
  • Adenocarcinoma / surgery
  • Colorectal Neoplasms / enzymology
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / pathology*
  • Colorectal Neoplasms / surgery
  • Female
  • Gastric Mucosa / enzymology
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Intestinal Mucosa / enzymology
  • Lymphatic Metastasis
  • Male
  • Neoplasm Invasiveness
  • Neoplasm Staging
  • RNA, Messenger / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Stomach Neoplasms / enzymology
  • Stomach Neoplasms / genetics
  • Stomach Neoplasms / pathology*
  • Stomach Neoplasms / surgery
  • Superoxide Dismutase / genetics*
  • Transcription, Genetic*


  • RNA, Messenger
  • Superoxide Dismutase