Detection Of Urokinase-type Plasminogen Activator Receptor And Its Clinical Significance In Lung Cancer

Objective To study the expression of urokinase-type plasminogen activator receptor (uPAR) in the tumor tissue and the peripheral blood to investigate its value for the metastasis and prognosis of lung cancer.Methods The expression of uPAR in 52 pulmonary tissues obtained through thoracic operation and bronchoscopy were examined by S-P immunohistochemical technique. The plasma levels of suPAR in 26 normal adults, 54 patients suffered from lung cancer were measured by using enzyme linked immunosorbent assay (ELISA).Results (1) The positive rate of uPAR in the lung cancer cases was 88.89% and that in the non-malignant cases was 6.25%. The difference of the two groups was statistically significant (PO.0001), but the expression of uPAR in the lung cancer did not show a significant correlation with age, gender and histological classification (P>0.05) . (2) The mean levels of suPAR were 1.884 + 0.103 ug/L in plasma of 26 normal adults, while that in plasma of 54 lung cancer patients were 3.498 + 0.162 ug/L. The plasma suPAR levels of lung cancer patients were increased in comparision with that of normal adults (PO.001). The suPAR levels in the lung cancer patients did not show a significant correlation with age, gender and histological classification (P>0.05), but were related to TNM stage (P<0.05). Our preliminary date show that high levels of suPAR were associated with worse survival of the patients andthe suPAR levels paralleled with the expression of uPAR in the tumor tissue.Conclusion There are expression of uPAR in the tumor tissue and the peripheral blood from the lung cancer patients, and uPAR plays a central role in promoting tumor growth, invasion and metastasis. Measurement of suPAR in lung cancer patients' blood may have value in assessment of prognosis and tumor recurrence. Plasma suPAR would be more reliable and convenient indicator in monitoring uPA system, and could be used as a new tumor marker in clinic.