Relationships between the level of matrix metalloproteinase-2 and tumor size of breast cancer

Background: The involvements of matrix metalloproteinase-2 (MMP-2) in the pathogenesis of breast cancers have been established. We determined the concentrations of MMP-2 in serum samples and tumor tissues of breast cancer patients. Methods: Gelatin zymography and ELISA were used to measure MMP-2 and MMP-9 concentrations in 90 breast cancer patients, including 60 tissue samples and 30 serum samples. Results: ProMMP-2, activated MMP-2, proMMP-9 and activated MMP-9 levels were significantly higher in tumor tissues than that of corresponding paired adjacent normal tissue of 60 breast cancer patients (p < 0.01). Further linear regression analysis has showed that the tumor size positively correlated with MMP-2 level in tumor tissue samples (R = 0.55, p < 0.0001), as well as with that of in serum samples (R = 0.398, p = 0.032). In addition, further statistical analysis for clinic pathological parameters revealed that MMP-2 level was significantly increased in patients with metastasis (p < 0.05). Furthermore, MMP-2 level was significantly different between tumor grades (p = 0.006). Conclusions: MMP-2 levels in serum and tumor tissue might reflect the severity of invasion of breast cancer and various MMP inhibitors might be selectively used as potential anti-metastasis agents according to tumor size.