Objective: To study the expression and role of pRb in 7,12-dimethylbenzanthracene(DMBA) induced hamster buccal pouch carcinogenesis.
Methods: DMBA (0.5%) in acetone was applied to the right buccal pouch 3 times per week for up to 12 week. Paraffin-embedded sections were used for pRb immunohistochemical determination (ISAB technipue, polyclonal antibody c-15 for pRb). The density of staining was analysed by rank sum test.
Results: The positive staining of pRb was strong in normal buccal epithelium, no alteration of pRb staining in 3 week (hyperplastic epithelium) and somewhat reduced between 6 and 9 week (dysplastic lesion), but it was marked reduced in 12 week (carcinoma). Statistical analysis found that changes of pRb were associated with stages of carcinogenesis.
Conclusion: These results indicate that abnomal expression of Rb gene product could be related to oral carcinogenesis and may serve as a biomarker for supervising oral malignancy.