As a result, low expression level of STT3A can support the immune activity in thyroid cancer tissue, which increases inflammatory mediators, cytokines, chemokines, reactive oxygen species in the tumor immune microenvironment and promotes tumor progression. MTHFD1 and GSTM4 are enzymes of folate metabolism and glutathione metabolism, and both of them have been reported to be related to immunodeficiency and tumor [36, 37]. Here, MTHFD1 is linked to immune system disorder.