UGT1A1 and colonic neoplasm: At present, cells commonly used for the study of miRNA and UGT1As are human primary hepatocytes, hepatoma cell lines (HepG2 and HuH-7, which express high levels of UGT1As and are easy to transfect), a human embryonic kidney cell line (HEK293, which is easy to transfect, stably expresses several UGT1As, and is a commonly used cell line for studying foreign genes), and colon cancer cell lines (LS180, LS174T, and CaCo-2, which have high UGT1A expression and glucuronidation activity).