Furthermore, immunohistochemical staining analysis revealed that in the tumor tissues of the sh-circSIRT5 group, the expression levels of PHGDH and SLC7A11 were significantly higher than in the sh-NC group, whereas in the circSIRT5 overexpression group, the expression levels of PHGDH and SLC7A11 were markedly lower than in the Vector group. Here, PHGDH is linked to neoplasm.