TNF and neoplasm: Wang et al. (2019) found that CD8+ T cells release cytokines, including tumor necrosis factor and interferon γ, to drive tumor cell killing by regulating ferroptosis. Co-stimulation has been found to promote the proliferation and survival of CD8+ T cells and Tregs (Chen and Flies, 2013). Combining our results, we suspect that increased T cell costimulation in patients in the high-risk group may promote the proliferation of CD8+ T cells and Tregs, increasing their content in ESCA. The increased CD8+ T cells release interferon γ to improve the response of interferon γ to regulate ferroptosis.