[The expression and clinical implication of inducible nitric oxide synthase mRNA in laryngeal carcinoma and hypopharyngeal carcinoma].

OBJECTIVE

To study the expression of inducible nitric oxide synthase(iNOS) mRNA in laryngeal carcinoma and hypopharyngeal carcinoma and its clinical significance.

METHOD

The tissue samples (laryngeal carcinoma, 40; hypopharyngeal carcinoma, 12; adjacent tissue, 50; laryngeal papilloma, 10; amyloidosis of larynx, 2; and normal laryngeal mucosa, 7) were examined by reverse transcription-polymerase chain reaction(RT-PCR).

RESULT

1. The target gene of iNOS were detected in 41 of 52 tumor tissues, 10 of 50 adjacent tissues, 5 of 12 benign tumor tissues and 0 of 7 normal tissues. The difference was significant (P < 0.0001, P < 0.005, P < 0.0001); 2. No significant difference was found among the expression of iNOSmRNA in different primary locations, there was significant statistical difference between the early clinical stages (T1-T2) and the advanced stages (T3-T4); 3. The poorly differentiated tumor cell showed a higher iNOSmRNA expression than that in moderate differentiated tumor cell (P < 0.05) and the iNOSmRNA expression in the lymph node metastasis group was higher than the non-metastasis group (P < 0.05).

CONCLUSION

It suggests that iNOS gene expression occurs in human laryngeal carcinoma and hypopharyngeal carcinoma, it might involve in the development of head and neck neoplasms in gene level by generating NO.