Evaluation of matrix metalloproteinase-2 expression in cervical carcinogenesis using tissue array and integrated optical density for immunoreactivity

To correlate matrix metalloproteinase-2 (MMP-2) expression with cervical carcinogenesis, the authors use reverse-transcription polymerase chain reaction to detect MMP-2 mRNA expression in 10 cervical squamous cell carcinoma (SCC), 10 high-grade cervical intraepithelial neoplasia (CIN), and 10 normal tissues. They further detect MMP-2 immunoreactivity of 24 tissue cores in each SCC, high-and low-grade CINs, and a healthy subgroup on a tissue array using integrated optical density (IOD) for number and intensity of stained cells in 345 × 345 pixels. They found the mRNA expression of MMP-2 to be higher in most SCCs (9/10 samples) and high-grade CINs (7/10 samples) but lower in normal tissues. The IOD of MMP-2 was significantly higher in high-grade CIN than in normal and low-grade CIN tissue cores (P < .001 for both) and significantly higher in SCC than in high-grade CIN tissue cores (P <.001). The results show that MMP-2 upregulation confers on tumor cells the ability to degrade the subepithelial basement membrane and subsequently invade the cervix.