SHMT2 and intrahepatic cholangiocarcinoma: In addition, previous reports have indicated that SHMT2 expression is upregulated in various types of cancer, including hepatocellular carcinoma (Ji et al., 2019), intrahepatic cholangiocarcinoma (Ning et al., 2018), breast cancer (Bernhardt et al., 2017) and gastrointestinal tumors (Liu et al., 2019).