We focused our attention on 2 genes, PTCH1 and IGF1, and we compared the expression of both genes in 1085 breast cancers versus 291 normal breast tissues and 492 prostate cancers versus 152 normal prostate tissues (Figures 8a and 8b) Both genes resulted significantly downregulated in the tumor group compared to the normal one except for the PTCH1 gene in prostate cancer (Figure 8a). Here, PTCH1 is linked to prostate cancer.