Browsing by Author "Selemetjev, Sonja (24463032600)"

Aim: To gain a better insight into the differences in biological behaviour between papillary microcarcinoma (PMC) and clinically evident papillary thyroid carcinoma (PTC). Methods: Immunohistochemical analysis of apoptosis related molecules (Bcl-2, Bax, p53) and proliferation related marker (PCNA) in 39 archival cases of PMC and 46 cases of PTC. Results: Bcl-2 and Bax were expressed in most PMCs and PTCs. The average Bcl-2 staining score did not differ significantly between PMCs and PTCs (p > 0.05), but the average Bax score was significantly lower in PMCs (p < 0.05). The Bcl-2/Bax ratio was significantly higher in PMCs than in PTCs (p < 0.05). The expression of p53 was similar in PMCs and PTCs, without a correlation with clinical data, but was associated with high Bax expression (p < 0.05) in these cases in both groups. Non-malignant tissue expressed only Bcl-2, but not p53 or Bax. PCNA expression was significantly lower (p < 0.05) in PMC than in PTC and positively correlated with tumour size (p < 0.05). Conclusions: The higher Bcl-2/Bax ratio and lower proliferative activity in PMC suggest differences from PTC in the balance between apoptosis and proliferation. However, the presence of p53 and Bax in PMC indicates malignant potential, and thus PMC should be treated with caution. © 2008 Royal College of Pathologists of Australasia.

Purpose: Papillary thyroid carcinoma (PTC) has a strong propensity to metastasize to regional lymph nodes which increases the risk of local-regional relapse and affects the course of the disease. Molecular pathogenesis of lymph node metastasis (LNM) is not yet fully understood. Survivin, a multifunctionale molecule involved in apoptosis, proliferation and angiogenesis, and vascular endothelial growth factor-C (VEGF-C) are suggested to be implicated in lymphatic metastases of human malignancies. Materials and Methods: Expression of survivin and VEGF-C was examined by immunohistochemistry and Western blot in 75 cases of PTCs in relation to their LNM status. Additionally, survivin and VEGF-C were immunohistochemically analyzed in 15 primary PTCs paired with their metastatic tissue in lymph nodes. Results: High expression of survivin and VEGF-C was found in 62.7% and 64.0% cases, respectively, with a positive correlation to each other (Spearman's correlation co-efficient = 0.878, P < 0.001). Expression levels of both proteins were significantly higher in patients with LNM than in those without LNM (P < 0.001). The rate of concomitant high expression of survivin and VEGF-C in patients with LNM involvement was 88.9% (P < 0.01). Metastatic tissue in lymph nodes expressed survivin and VEGF-C at the same high extent as their primary tumors. Conclusion: Concomitant high expression of survivin and VEGF-C is closely associated with LNM status of PTC patients, which suggests their cooperation in the metastatic process. Evaluation of survivin and VEGF-C expression could be clinically significant in predicting the metastatic potential of PTC and subsequent treatment and follow-up of these patients. © 2017 Journal of Cancer Research and Therapeutics.