IGF1 and ischemic disease: In contrast, the expression of the senescence factor P21 decreased in the S and APCS groups compared with that in the 2D group.[30] Next, we analyzed the expression of ischemic disease‐associated HIF‐1α signaling‐regulated factors VEGF, COX‐2, IGF‐1, ANGPT‐1, and IL‐8, all involved in angiogenesis, and found expression of these genes was significantly enhanced in the S and APCS groups than that observed in the 2D group.