The clinical significance of the expression of urokinase type plasminogen activator and plasminogen activator inhabitor in thyroid carcinomas

Objective:To investigate the expression of urokinase type plasminogen activator(uPA) and plasminogen activator inhibitor(PAI-1) in the tissue of thyroid carcinomas,sum up the role of these factors in the occurrence,progression,invasion in thyroid carcinomas and their significances for clinical practice.Methods:The levels of uPA and PAI-1 in tissue was determined by ELISA method in 42 cases of thyroid carcinomas,30 cases of benign thyroid tumor and normal thyroid tissues.The levels of these two factors were compared between benign and malignant diseases,various clinical stages and different pathologic types.Results:The level of uPA in thyroid carcinomas tissue was significantly higher than that of normal group(P0 05),but the level of PAI-1 was not different between two groups.The level of uPA and PAI-1 in tissue of thyroid carcinomas were significantly higher than that in benign tumour tissue and in tissues beside carcinomas(P0 01),and were positively correlated to clinical stages of thyroid tumor,Compared with the group of no lymph node metastasis,the uPA level in lymph node metastasis group was higher(P0 05).The level of uPA and PAI-1 in anaplastic thyroid cancer was higher than that in papillary thyroid cancer and follicular thyroid cancer(P0 05).There was no different levels of these two factors between papillary thyroid cancer and follicular thyroid cancer.In comparison with other kind of cancers,the level of uPA and PAI-1 in medullary thyroid cancer was lowest.Conclusion:Measuring levels of uPA and PAI-1 in tissues may help to evaluate the extent of cancer invasion,lymph node metastasis and prognosis of thyroid cancer.