Korean J Oral Maxillofac Radiol.  2000 Sep;30(3):207-216.

The Effect of Irradiation on the Expression of PCNA and Apoptosis Induction during the DMBA Induced Carcinogenesis in Hamster Buccal Pouch

• Jeon IS
• Heo MS
• Choi HM
• Lee SS
• Choi SC

Abstract

PURPOSE: This study was carried out to investigate the effect of irradiation on the expression of proliferating cell nuclear antigen (PCNA) and apoptosis induction during the carcinogenesis in hamster buccal pouch.
MATERIALS AND METHODS
Three months old Syrian golden hamsters were divided into control and 2 experimental groups. Hamsters in control group were left untreated on buccal pouchs. Twenty four hamsters were treated with 0.5% DMBA tri-weekly on the right buccal pouch. Forty eight hamsters were treated with 0.5% DMBA tri-weekly and irradiated with the dose of 5 Gy and 10 Gy at 6, 9, 12, 15 weeks after DMBA application. Resected buccal pouches were sectioned and examined for potential expression pattern of PCNA and apoptosis.
RESULTS
The PCNA index was increased with the stages of buccal pouch epithelium carcinogenesis except the hyperplasia stage in control group (p<0.05). The irradiation did not effect on the PCNA index in the dysplasia and the carcinoma in situ stage, but in the hyperplasia stage, the PCNA index was increased with 10 Gy radiation and decreased in the carcinoma stage (p<0.05). The apoptotic index was significantly decreased from the carcinoma in situ stage and the lowest in the carcinoma stage. The apoptotic index was significantly decreased in the hyperplasia and dysplasia stage with the 5 Gy irradiation and significantly increased only in the carcinoma stage with the 10 Gy irradiation (p<0.05).
CONCLUSION
The PCNA and apoptotic index were varied according to the irradiation period and dosage in each carcinogenesis stage.

Keyword

proliferating cell nuclear antigen; apoptosis; neoplasm; radiation

MeSH Terms

9,10-Dimethyl-1,2-benzanthracene*
Animals
Apoptosis*
Carcinogenesis*
Carcinoma in Situ
Cricetinae*
Epithelium
Hyperplasia
Mesocricetus
Proliferating Cell Nuclear Antigen*
Radiation Dosage
9,10-Dimethyl-1,2-benzanthracene
Proliferating Cell Nuclear Antigen