Published online Nov 15, 2003. doi: 10.3748/wjg.v9.i11.2592
Revised: May 21, 2003
Accepted: June 2, 2003
Published online: November 15, 2003
AIM: Type IV collagenase participates in invasion and metastasis of cancer cells. Malignant ascites is a manifestation of advanced malignant disease that is associated with invasion and metastasis of the peritoneal cavity. Thus, it is reasonable to hypothesize that type IV collagenase is linked to malignant ascites. The purpose of our study was to detect type IV collagenase activity in malignant ascites so as to provide the scientific basis for clinic diagnosis and treatment of malignant ascites.
METHODS: Cirrhotic ascites (n = 36), tuberculous ascites (n = 8) and malignant ascites (n = 23) from patients with gastric cancer (n = 6), colon cancer (n = 5), ovarian cancer (n = 8) and other cancers (n = 4), including 2 hepatocellular cancers, 1 pancreatic cancer, 1 primary peritoneal carcinoma were collected by paracentesis. The ascites were made cell-free by centrifugation and stored frozen at -70 °C before determination. Type IV collagenase activity was determined by gelatin zymography.
RESULTS: The activity of matrix metalloproteinases-2 and -9 could not be detected in ascites of hepatic cirrhosis and tuberculous peritonitis but could be detected in 20 and 18 out of 23 malignant ascites respectively. The positive rate of type IV collagenase (MMP-2, 87.0% and MMP-9, 78.3%) was higher than that by routine ascites tests (P < 0.01) in malignant ascites. Furthermore, the activity of MMP-2 was higher than that of MMP-9 (P = 0.022 < 0.05).
CONCLUSION: Type IV collagenase is positive in malignant ascites. Detection of type IV collagenase activity is useful in qualitative diagnosis of ascites. Type IV collagenase may play an important role in malignant ascites formation.