Relationship between pathogenesis of chronic skin ulcer and overexpression of Ras and C-myc

Abstract

Objective To explore the relationship between the abnormal overexpression of Ras and C-myc in chronic ulcers of the skin and the pathogenesis of squamous cell carcinoma (SCC) in Marjolin′s ulcer. Methods Ten tissue specimens of SCC in Marjolin′s ulcer, ten tissue specimens of chronic skin ulcer accompanied with pseudoepitheliomatous hyperplasia, ten tissue specimens of primary SCC, and five tissue specimens of normal skin were collected. The expression of Ras and C-myc in these specimens was detected by immunohistochemistry. Results Both Ras and C-myc were overexpressed in the tissues of SCC in Marjolin′s ulcer. The nuclear staining of Ras and C-myc was positive in some carcinoma cells. However, they were negatively expressed in normal skin tissue and primary SCC cells. They were also not expressed in the epithelial cells with atypical hyperplasia in chronic skin ulcer accompanied with pseudoepitheliomatous hyperplasia. Conclusion The abnormal expression of Ras and C-myc is closely related to the carcinogenesis in chronic ulcer. Key words: Marjolin′s ulcer; Squamous cell carcinoma; Chronic skin ulcer; Ras; C-myc