[Expression and prognostic significance of cyclooxygenase-2 in supraglottic laryngeal squamous cell carcinomas]

To study the expression and prognostic significance of cyclooxygenase-2 (Cox-2) in supraglottic laryngeal squamous cell carcinomas (SGLSCC) and identify the relationship between Cox-2 and angiogenesis and the roles of Cox-2 in SGLSCC as a biological marker.

Eighty-eight primary SGLSCC patients received surgical treatment were studied by immunohistochemical staining, and reverse transcription-polymerase chain reaction (RT-PCR) technique.

The percentage of Cox-2-positive cells was 94.3% (83/88) in SGLSCC whereas there was no immunostaining in the all cells of normal mucosa of paracarcinoma. Cox-2 expression was higher in well-differentiated tumors compared with poorly-differentiated SGLSCC. The relative concentration of Cox-2 mRNA was 141.871 +/- 20.5435 in SGLSCC and 17.031 +/- 2.2597 in normal paracarcinoma mucosa (P < 0.01). It was significantly higher in SGLSCC than in normal paracarcinoma mucosa. In SGLSCC, only pathological grading and the percentage of Cox-2-positive cells had significant correlation (P < 0.01). And not only the percentage of Cox-2-positive cells but also Cox-2 intensity had significant correlation with microvessel density (MVD) (P < 0.01). Kaplan-Meier survival analysis showed there had significant relationship between Cox-2 intensity and cumulative survival rate of SGLSCC patients (P < 0.05). But the percentage of Cox-2-positive cells was different (P > 0.05). Cox's regression analysis indicated that Cox-2 intensity were significantly independent prognostic factors (P < 0.01).

Cox-2 expression maybe relate to the carcinogenesis and progress in tumors especially in well-differentiated ones; The changes of Cox-2 expression are synchronous with MVD. Cox-2 intensity is a significantly independent prognostic factor. So Cox-2 may be an effective target of prevention, therapy and prognostic evaluation for laryngeal carcinoma and other head and neck squamous cell carcinomas (HNSCC).