adenosine-5--(n-ethylcarboxamide) and Carcinoma--Squamous-Cell

The presence of intratumoral lymphatic vessels (ILVs) and the expression of vascular endothelial growth factor-C (VEGF-C) in tumour cells have been studied as markers of lymphangiogenesis in order to evaluate their role in metastatic dissemination in laryngopharyngeal squamous cell carcinoma.. A retrospective study was performed in 76 patients of N0 laryngopharyngeal carcinoma. with variable tumour size (T1-T4), histological grade, and location (supraglottic, glottic and hypopharyngeal). The presence of ILVs, as revealed by the expression of PA2.26 antigen and VEGF-C expression, were determined by immunohistochemistry (IHC). Low-grade and high-grade lymphangiogenesis were defined by qualitative and quantitative criteria.. Multivariate analysis revealed low-grade ILV and VEGF-C expression to be associated respectively with 30.3- and 16.2-fold higher probabilities of cervical lymph node relapse (P = 0.005 and P = 0.032) and with 16.2- and 8.44-fold shorter disease-free survival (P = 0.009 and P = 0.045).. Low-grade ILV and VEGF-C expression are independent predictive factors of cervical lymph node relapse and shortening of time to relapse in N0 laryngopharyngeal carcinoma.

Topics: Adenosine-5'-(N-ethylcarboxamide); Adult; Aged; Aged, 80 and over; Carcinoma, Squamous Cell; Female; Humans; Laryngeal Neoplasms; Lymphangiogenesis; Lymphatic Metastasis; Lymphatic Vessels; Male; Middle Aged; Pharyngeal Neoplasms; Vascular Endothelial Growth Factor C

The activation of A1 and A2 adenosine receptors was shown to modulate DNA synthesis. In A431 cells, low concentrations of adenosine (approximately 10 microM) inhibited while higher concentrations (approximately 100 microM) stimulated [14C]thymidine incorporation. Epidermal growth factor (EGF) (10 ng/ml) could partially alleviate the inhibitory effects and further enhance the stimulatory effects of adenosine. Treatment of the cells with adenosine analogues (R-PIA and NECA) and antagonists (theophylline and DPCPX), which are selective for either the A1 (inhibitory) or A2 (stimulatory) receptors, indicated the involvement of these two receptors in the biphasic response to adenosine.

Topics: Adenosine; Adenosine-5'-(N-ethylcarboxamide); Carcinoma, Squamous Cell; DNA, Neoplasm; Epidermal Growth Factor; Humans; Phenylisopropyladenosine; Purinergic P1 Receptor Antagonists; Receptors, Purinergic P1; Theophylline; Tumor Cells, Cultured; Xanthines