Correlation of the in situ detection of polymerase chain reaction-amplified metalloproteinase complementary DNAs and their inhibitors with prognosis in cervical carcinoma.
The purpose of this study was to correlate the presence of matrix metalloproteinase (MMP)-9 and MMP-2 and tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 mRNAs, detected in serial sections using the reverse transcriptase in situ PCR technique, with prognosis in 23 cases of cervical carcinoma. PCR-amplified MMP and TIMP cDNA were restricted to the invasive cancers cells and the surrounding stromal cells. The ratios of cancer and stromal cells expressing MMP-9 and MMP-2 to those expressing TIMP-1 and TIMP-2 were approximately 1 in those cancers with a good prognosis. This MMP:TIMP ratio in the cancer and stromal cells with a poor prognosis was significantly increased to 5.4 and 3.4 (P < 0.0001), respectively, reflecting a marked reduction in the TIMP detection rate in cancers with a poor prognosis. In cervical cancer cell lines SiHa and HeLa, the MMP:TIMP ratio was also close to 1 and, interestingly, these cell lines are invasive but rarely metastatic in nude mice. These data suggest that the balance of MMP-9 and MMP-2 to TIMP-1 and TIMP-2 expression is an essential factor in the aggressiveness of cervical cancer.