title: Expression of cystatin C in human esophageal cancer.
abstract: OBJECTIVE
  Cystatin C is a member of the cysteine protease inhibitors and its function is to decrease protease activity. A recent study showed that it was aberrantly expressed in many malignant tumors in association with tumor invasion and metastasis. We attempted to detect its expression in esophageal cancer tissues and adjacent reparative normal tissues.
  
  
  METHODS
  Samples of cancers and non-cancerous esophageal tissues were obtained as matched pairs from 30 surgery patients with esophageal cancer and paraffin embedded. The expression of cystatin C in tissues was investigated by immunohistochemistry. Fisher's exact test was used to analyze the relationship between esophageal cancer tissues and adjacent normal tissues. Furthermore, mRNA was extracted, and reverse transcriptase polymerase chain reaction was performed.
  
  
  RESULTS
  The intensity of cystatin C immunostaining in tumor tissues was increased compared to that of adjacent normal tissues. mRNA expression of the cystatin C gene was greater in esophageal cancer than in normal tissues (P <0.05).
  
  
  CONCLUSIONS
  Our results indicate that cystatin C may play an important role in the pathogenesis and metastasis of esophageal cancer.
authors: Department of Microbiology and Immunology, The Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, China.
authors: Qinghong
authors: Q
authors: Zeng
authors: Yonggang
authors: Y
authors: Zhao
authors: Yuxian
authors: Y
authors: Yang
authors: Guiyu
authors: G
authors: Zheng
authors: Gefei
authors: G
authors: Wang
authors: Peng
authors: P
authors: Zhang
authors: Youhong
authors: Y
authors: Cui
authors: Shaobo
authors: S
authors: Su
authors: Kangsheng
authors: K
authors: Li