Expression of membrane-type 1, 2, and 3 matrix metalloproteinases messenger RNA in ovarian carcinoma cells in serous effusions

We studied the levels of matrix metalloproteinase (MMP)-2, membrane-type, ( MT)1-MMP, MT2-MMP, and MT3-MMP in 43 malignant pleural and peritoneal effus ions using reverse transcription-polymerase chain reaction (RT-PCR) and cel lular localization of MT1-MMP in 66 effusion specimens and 85 corresponding primary and metastatic tumors using messenger RNA (mRNA) in situ hybridiza tion (ISH). In 43 effusions, MMP-2 mRNA was detected in 37, MT1-MMP in 25, and MT2-MMP in 32. Expression of MT1-MMP and MT2-MMP was found in 21 specim ens; in 16 MT-MMP-positive specimens, mRNA for only 1 of 2 enzymes was expr essed. MT3-MMP mRNA was not detected. High levels of MMP-2 mRNA were detect ed more often in effusions with high MT1-MMP and/or MT2-MMP mRNA expression . Using ISH, MT1-MMP mRNA was localized to cancer cells in 27 of 58 maligna nt effusions; focal signals were detected in mesothelial cells in 7 of 42. MT1-MMP was localized to tumor cells in 32 of 85 primary and metastatic sol id lesions, and stromal cells expressed MT1-MMP in 3. Tumor cell MT1-MMP ex pression in effusion specimens did not differ from primary or metastatic le sions. MT-MMP expression in tumor cells in effusions showed no association with effusion site or tumor type using ISH and RT-PCR.