For example, caffeic acid phenyl propyl ester (CAPPE) and caffeic acid phenyl ethyl ester (CAPE), which are the better bioavailable versions of caffeic acid, significantly inhibited the growth of colorectal tumors in xenografted mouse models by decreasing the number of proliferating cells as evident by reduced expression of proliferating cell nuclear antigen (PCNA), and by inhibiting fatty acid synthetase (FASN) as well as matrix metalloproteinase 9 (MMP-9) [85]. Here, PCNA is linked to colorectal neoplasm.