Expression of matrix metalloproteinase-9 in pleural effusions of tuberculosis and lung cancer.
BACKGROUND
Matrix metalloproteinase (MMP)-9 has been implicated in the development of pleural effusions.


OBJECTIVE
The aim of this study was to assess the expression of MMP-9 in pleural effusions of tuberculosis, lung cancer and transudates.


METHODS
Ninety-one patients (37 tuberculous pleural effusions, 42 malignant pleural effusions of lung cancer and 12 transudates) were included. Concentrations of pleural fluid MMP-9 and tissue inhibitors of matrix metalloproteinase (TIMP)-1 were determined by immunoassay. We also investigated the cellular localization of MMP-9 and TIMP-1 by reverse-transcriptase polymerase chain reaction on lymphocytes from pleural effusions and by immunohistochemical analysis of pleural tissues.


RESULTS
Pleural fluid MMP-9 levels, MMP-9/total protein and MMP-9/TIMP-1 ratios were significantly higher in tuberculous pleural effusions, whilst TIMP-1 levels were similar in the three groups. MMP-9 levels positively correlated with TIMP-1 and lactate dehydrogenase levels, and negatively with pH and glucose levels in pleural effusions. MMP-9 mRNA expression in lymphocytes tended to be higher in malignant pleural effusions of lung cancer than in the other groups without reaching statistical significance. The strongest immunoreactivity for MMP-9 was observed in epithelioid cells of tuberculous pleural tissues. Much lower levels of MMP-9 expression were found in tumor cells of pleural tissues.


CONCLUSIONS
MMP-9 is increased in tuberculous pleural effusions compared with transudates and malignant pleural effusions of lung cancer and is produced predominantly by epithelioid cells in the granulomas of tuberculous pleural tissues.
Park
Kwang Joo
KJ
Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, South Korea. parkk2@mail.nih.gov
Hwang
Sung Chul
SC
Sheen
Seung Soo
SS
Oh
Yoon Jung
YJ
Han
Jae Ho
JH
Lee
Kyi Beum
KB
D000328:Adult; D001706:Biopsy; D002277:Carcinoma / Q000201:enzymology / Q000473:pathology; D003937:Diagnosis, Differential; D004587:Electrophoresis, Agar Gel; D045604:Extracellular Fluid / Q000166:cytology / Q000201:enzymology*; D005260:Female; D015870:Gene Expression / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D005819:Genetic Markers; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000201:enzymology* / Q000473:pathology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics* / Q000378:metabolism; D010994:Pleura / Q000201:enzymology / Q000473:pathology; D010996:Pleural Effusion / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D016066:Pleural Effusion, Malignant / Q000201:enzymology / Q000473:pathology; D012313:RNA / Q000235:genetics; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism; D014397:Tuberculosis, Pulmonary / Q000150:complications / Q000201:enzymology* / Q000473:pathology
D005819:Genetic Markers; D019715:Tissue Inhibitor of Metalloproteinase-1; D012313:RNA; D020780:Matrix Metalloproteinase 9