The urokinase plasminogen activating system in thyroid cancer: clinical implications

The urokinase plasminogen activator (uPA) system (uPAS) comprises the uPA, its cell membrane receptor (uPAR) and two specific inhibitors, the plasminogen activator inhibitor 1 (PAI-1) and 2 (PAI-2). The uPA converts the plasminogen in the serine protease plasmin, involved in a number of physiopathological processes requiring basement membrane (BM) or extracellular matrix (ECM) remodelling, including tumor progression and metastasis. The tumor-promoting role of PAS is not limited to the degradation of ECM and BM required for local diffusion and spread to distant sites of malignant cells, but widens to tumor cell proliferation, adhesion and migration, intravasation, growth at the metastatic site and neoangiogenesis. The relevance of uPAS in cancer progression has been confirmed by several studies which documented an increased expression of uPA, uPAR and PAI-1 in different human malignancies, and a positive correlation between the levels of one or more of them and a poor prognosis. For these reasons, the uPAS components have aroused considerable interest as suitable targets for anticancer therapy, and several pharmacological approaches aimed at inhibiting the uPA and/or uPAR expression or function in preclinical and clinical settings have been described. In the present manuscript, we will first glance at uPAS biological functions in human cancer progression and its clinical significance in terms of prognosis and therapy. We will then review the main findings regarding expression and function of uPAS components in thyroid cancer tissues along with the experimental and clinical evidence suggesting its potential value as molecular prognostic marker and therapeutic target in thyroid cancer patients.

Actual status of preoperative diagnosis of thyroid cancer in Albania

Introduction. Thyroid cancer is the most common endocrine malignancy and accounts for almost 1% of human cancer. It is well known that the majority of cases occur in women in the middle decades of life. Thyroid cancer is a relatively rare disease; on the other hand clinically apparent thyroid nodules are present in 4-7% of the adult population. Most thyroid nodules are not malignant, with reported malignancy rates from 3-12%. It is important for the surgeon to know beforehand the diagnosis of malignancy, in order to perform a more radical operation on the thyroid gland. Patients and Methods. In our study we have analyzed the preoperative clinical data of 84 patients operated in the First Clinic of General Surgery, UHC “Mother Theresa” in Tirana; all with a positive histopathologic diagnosis of thyroid cancer. The data comprised age, sex, age distribution, blood group, time-lapse from the first endocrinologic visit, clinical examination, signs and symptoms, imaging, functional tests, preoperative FNA, admission diagnosis, associated diseases and preoperative treatment. Results. From the study emerged that only 9,3% of these patients were diagnosed preoperatively as thyroid cancer. Another related problem is the low percentage of preoperative FNA – only 22%. Among the signs and symptoms related to thyroid cancer we found that 40 and 33% of these patient presented dyspnea and dysphagia, respectively. The physical examination revealed apparent nodular growth of the thyroid gland in 81% and nodular hard consistency in 79% of cases. The proper endocrinologist consultation lacked in 23% of cases. Conclusion. In our opinion, close collaboration between endocrinologists and surgeons in a multidisciplinary frame is the key to correct preoperative thyroid cancer diagnosis and optimal treatment.