Background: Vitamin D receptor (VDR) polymorphisms have important implications for vitamin D signalling and are associated with various malignancies.
Patients and methods: In a German population, the frequency of several VDR polymorphisms (Apa1, Taq1, Bgl1) in basal cell carcinomas (BCCs, n=90) and cutaneous squamous cell carcinomas (SCCs, n=100) as compared to healthy controls (n=51) was analyzed.
Results: Impressive variations in the frequency of some VDR genotypes were found when comparing skin of cancer patients and controls. An association of the genotype AaTtBb with BCC risk was found (BCC: 45.7%, SCC: 39.8% and controls: 38.0%). The genotype aaTTBB was exclusively found in the control group (20%), which suggested that this genotype may be protective against skin carcinogenesis. Moreover, the aaTTbb genotype was associated with skin cancer risk, being found at a much higher frequency in BCCs (21%) and SCCs (17%) as compared to controls (8.0%). Comparison of the frequencies of the VDR genotypes in sunlight-exposed vs. not sunlight-exposed skin areas revealed BB 30.1% vs. 7.1% respectively in BCCs and BB 28.1% vs. 0.0% respectively in SCCs, indicating that vitamin D signalling may be of importance for photocarcinogenesis of the skin. Associations also indicated that the Apa1 and Taq1 genotypes may be of importance for photocarcinogenesis of BCCs, but not for SCCs. Comparison of the VDR genotype frequencies by age (younger than 60 years vs. 60 years or older) revealed no evidence of age-dependent variations in patients with BCCs or SCCs.
Conclusion: VDR polymorphisms are of importance for the development of BCCs and cutaneous SCCs, but further explorations of these findings and their implications are required.