We have shown that VDR and VD3, known for their role in cancer prevention, also have a role in the regulation of oncogenic ΔNp63α, thus increasing keratinocyte proliferation at low VD3 concentration, bringing to light a drawback of the use of VD3 in cancer prevention and treatment.48, 49 Altogether these results suggest that VD3 can have either a growth-suppressive or growth-stimulatory role in the presence of VDR in keratinocytes cells by regulating the expression of ΔNp63α. Here, VDR is linked to cancer.