Some limited in vitro evidence suggests a direct link between the IGF-1/insulin axes and vitamin D. For example, laboratory studies on cultured the human prostate cancer cells the LNCaP human prostate cancer cell line have suggested that 1,25-dihydroxyvitamin D3 might influence IGFBP-3 levels [39], [40]. This evidence concerns the gene IGF1 and Familial prostate cancer.