To further explore the relationship between SDH5 and p53, we conducted an in vitro cell experiment and examined expression of the SDH5 protein in the following p53 wild-type lung cancer cell lines: A549, HCC827, and NCI-H292 cells expressing high levels of SDH5 and H226, NCI-H460, and H522 cells expressing low levels of SDH5. This evidence concerns the gene SDHAF2 and lung cancer.