TNF-α, a proinflammatory cytokine, is secreted by immune cells in the tumor microenvironment and is also secreted by tumor cells to play an oncogenic role in driving tumor progression and metastasis in multiple cancer types [41, 42], including PTC; in PTC, TNF-α induces epithelial‒mesenchymal transition to activate the metastatic and proliferative abilities of PTC cells [43]. This evidence concerns the gene TNF and cancer.