Identification of a DNA damage repair gene‐related signature for lung squamous cell carcinoma prognosis

BACKGROUND: DNA damage repair (DDR) plays a role in the tumorigenesis and progression of lung squamous cell carcinoma (LUSC), but the predictive value of DDR in LUSC has not been fully elucidated. METHODS: The LUSC datasets were retrieved from the Cancer Genome Atlas databases. Univariate Cox regression and least absolute shrinkage and selection operator regression were integrated to identify critical genes and construct a DDR gene signature. We performed Kaplan–Meier (KM) curve to compare the overall survival (OS) between the two groups based on DDR signature and used the CIBERSORT tool to compare the immune cell composition. Further gene set enrichment analysis (GSEA) was performed on the differential expressed genes. RESULT: We established the DDR‐related gene signature on LUSC. KM curve showed the low‐risk group had a better prognosis than the high‐risk group in the training set (p = 0.022673) and the complete set (p = 0.003201). The area under receiver operating characteristic curve for OS was 0.98, 0.96, and 0.97 in the training dataset, testing dataset, and the complete dataset, respectively. The composition of immune cells was different between the high‐ and low‐risk group. The GSEA result suggests that genes of the patients in low‐risk group were mainly enriched in the DNA adducts; drug metabolism‐cytochrome P450, metabolism of xenobiotics by cytochrome P450. CONCLUSION: This study identified DDR‐associated potential biomarkers related to overall survival of LUSC and establishes the DDR‐associated gene signature.