In cultured VSMCs, treatment with PGE1-OH or infection of Ad-EP4 also significantly upregulated the mRNA levels of genes related to cell proliferation including Ki67, Foxm1, Ccna2, Ccnb1, Ccnd1, Ccnd2, Ccne1, and CDK2 (Figure S4C,D). This evidence concerns the gene CCND1 and infection.