thromboxane-a2 and Carcinoma--Squamous-Cell

In order to evaluate the possible role of prostaglandins (PG) in invasion and metastasis of malignant cells in larynx carcinoma, arachidonic acid (AA) metabolite production by tumor tissue, peritumor tissue and node metastasis was investigated in comparison to that by healthy mucosa and unaffected lymph nodes. The study was performed by evaluating PGE2, 6ketoPGF1 alpha and thromboxane B2 (TXB2) production by radioimmunoassay in specimens from eight patients who underwent surgical treatment. The highest rate of AA metabolism was observed in peritumor tissue. PGE2 was the main metabolite produced in all tissues and its levels were significantly higher than those of 6ketoPGF1 alpha and TXB2 (p < 0.05). 6ketoPGF1 alpha production was higher (p < 0.01) than that of TXB2 and did not significantly change among the different tissues. TXB2 production was significantly increased (p < 0.05) by peritumor tissue as compared to healthy mucosa. The ratio between TXB2 and 6ketoPGF1 alpha production was found to be almost twofold higher in tumor tissue, peritumor tissue, metastatic and non-metastatic lymph nodes as compared to control tissue. The lowest AA metabolism was found in affected lymph nodes. These findings demonstrate a different AA metabolism at primary tumor sites in comparison to healthy mucosa suggesting a prometastatic role of TXB2 and supporting the hypothesis of the occurrence of an imbalance between TXB2 and 6ketoPGF1 alpha production in favouring metastatic spread.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Aged; Carcinoma, Squamous Cell; Dinoprostone; Epoprostenol; Humans; Laryngeal Neoplasms; Lymph Nodes; Lymphatic Metastasis; Middle Aged; Radioimmunoassay; Thromboxane A2

Arachidonic acid metabolites (AAm) have important regulatory functions within several areas of otorhinolaryngology: modulation of immune and allergic responses, inflammation, allergy, etc. The aetiology of vocal fold polyps is still obscure as are the possible mechanisms responsible for their forming and developing. The aim of this study was therefore to investigate the relationship between release of prostaglandins (PGE2, PGI2) and tromboxans (TxA2) from vocal fold polyps ex vivo in 21 patients, in comparison to normal airway mucosa. The production of PGE2 by vocal fold polyps was less than in the controls (ng/ml) (0.5 +/- 0.54; n = 21 vs. 1.09 +/- 0.78; n = 21) (p less than 0.05) but higher than in nasal polyps (0.14 +/- 0.11; n = 16) (p less than 0.01). Prostacyclin production by vocal fold polyps (0.99 +/- 0.92) was less than in control mucosa (2.24 +/- 1.93) (p less than 0.01), but higher than by nasal polyps (0.26 +/- 0.14) and less than in controls (0.99 +/- 0.73) (p less than 0.01) or nasal polyps (0.52 +/- 0.04) (p less than 0.01).

Topics: Adult; Carcinoma, Squamous Cell; Dinoprostone; Epoprostenol; Female; Humans; Laryngeal Neoplasms; Male; Middle Aged; Nasal Mucosa; Nasal Polyps; Polyps; Radioimmunoassay; Thromboxane A2; Vocal Cords

Circulating prostaglandins, including thromboxane A2 and prostacyclin, have been implicated as possible facilitative agents in the growth and dissemination of squamous cell carcinomas of the head and neck. The purpose of this study was to evaluate the relationship of plasma concentrations of these compounds to tumor stage and the effect of surgical resection on plasma prostaglandin levels. Blood samples were obtained from 40 patients with head and neck cancer. Ten treated patients were clinically disease-free (NED), and 30 patients with active disease were previously untreated at the time of this study. Plasma concentrations of thromboxane A2 and prostacyclin were measured by radioimmunoassay of their stable metabolites thromboxane B2 (TxB) and prostaglandin 6-keto-F1 (PGI). Platelet aggregation was performed with normal donor platelets (PRP) and normal control or patient plasma (PPP). TxB and TxB/PGI ratios were increased in T1N0M0 patients, compared with NED and with T4N0M0 primary lesions versus all other groups. With lymphatic and hematogenous metastases, TxB and TxB/PGI ratios fell to NED levels. ADP-induced platelet aggregation was significantly increased in head and neck cancer patients, compared with normal controls, and with T4N0M0 lesions, compared with NED. There were no significant differences in PGI levels. TxB, PGI, TxB/PGI, and platelet aggregometry did not change significantly with curative surgery. TxB and TxB/PGI interactions are involved in head and neck cancer. Changes in TxB and TxB/PGI may be related to increased platelet aggregation.

Topics: 6-Ketoprostaglandin F1 alpha; Aged; Aged, 80 and over; Carcinoma, Squamous Cell; Epoprostenol; Female; Head and Neck Neoplasms; Humans; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Staging; Platelet Aggregation; Thromboxane A2; Thromboxane B2