gms | German Medical Science

Introduction: Squamous Cell Carcinomas (SCCs) of the larynx emerge at the end of carcinogenesis, a multistage sequence involving epithelial aberrations of progressing severity, such as hyperplasia, dysplasia and carcinoma in situ. Even fully developed invasive tumors still progress to less differentiated forms of higher Grade. This morbid process could be reversed by promising pharmacological agents which target retinoid receptors, mainly Retinoid X Receptor (RXR). The present study notes RXR fluctuations, stepwise in the course from normal epithelium to anaplastic carcinomas.

Materials and methods: RXRα expression in laryngeal tissue samples from 127 patients with premalignant lesions and SCCs, who had undergone biopsy or laryngectomy, was immunohistochemically evaluated.

Results: Normal squamous epithelium expresses RXR stronger than normal respiratory type (P=0.002). During laryngeal carcinogenesis, RXR declines steadily in precancerous lesions and finally SCCs (P<0.001). No significant change among carcinomas of different Grade was recorded, however.

Conclusion: RXR is down-regulated as cells acquire a premalignant and malignant phenotype, whereas it does not seem to participate in tumor progression. Retinoids might be effective in chemoprevention of laryngeal cancer.