Given that studies have shown that reduced SM22α levels have a proliferative effect in vascular smooth muscle cells and prostate tumor cells [52, 53], and that SM22 levels were significantly reduced in proliferating cells in prostate, lung, breast, gliobrastoma and colorectal cancers [54–56], it is perhaps not surprising that PECs had higher proliferation in mice deficient in SM22α. This evidence concerns the gene TAGLN and colorectal cancer.