[Expression of DeltaNp63 protein in nasopharyngeal carcinoma and its significance].

BACKGROUND & OBJECTIVE: The molecular etiology of nasopharyngeal carcinoma is currently unknown. It was reported that DeltaNp63 is dominant-negative toward transactivation of p53, and associated with the malignant hyperplasia and dedifferentiation of the squamous cells. This study was designed to investigate the expression and significance of DeltaNp63 protein in NPC tissues.

METHODS

Immunohistochemical method was used to determine the expression of DeltaNp63 in 60 cases of NPC, 37 cases of nearby mucosa of the carcinoma, and 30 cases of chronic inflammation of nasopharyngeal mucosa. The classification of the 60 NPC cases were as follows: 3 cases of keratinizing squamous cell carcinomas, 57 cases of nonkeratinizing carcinomas including 12 cases of undifferentiated carcinomas.

RESULTS

All 60 NPC cases showed DeltaNp63 positive reaction. Keratinizing squamous cell carcinomas showed weakly positive expression; 66.67% (38/57) of nonkeratinizing carcinomas showed strongly positive reaction, and 83.33% (10/12) of undifferentiated carcinomas showed strongly positive reaction. Chronic inflammation mucosas and cancer nearby mucosas showed positive reaction only in their basal and superbasal cells.

CONCLUSION

DeltaNp63 protein was found to be closely associated with cell malignant hyperplasia. DeltaNp63 protein has distinct tendency to the infantile or anaplastic squamous cells, and DeltaNp63 protein is a valuable diagnostic marker for anaplastic squamous cells.