Investigation of radiation-induced DNA damage repair-related genes as diagnostic biomarkers for radiation.

Radiation exposure is a significant risk factor for various tumors and illnesses, with early-stage radiation dose closely linked to disease progression. Accurate assessment of radiation exposure is critical for effective treatment. This study aimed to identify radiation-induced DNA damage repair-related genes using weighted gene co-expression network analysis on datasets GSE90909 and GSE102971, supplemented by literature. A protein-protein interaction network was constructed to identify key genes, and their expression levels were compared between irradiated and control groups to evaluate diagnostic efficacy. Immune-related scores were calculated, and correlations between diagnostic genes and immune cells were analyzed. Regulatory networks involving transcription factors (TFs), microRNAs (miRNAs) and key genes were established, alongside gene interaction networks using GeneMANIA. A gene-drug interaction network was also developed. Five key genes-PCNA, REV3L, POLH, LIG1 and XPC-were identified, all significantly overexpressed in irradiated populations. These genes demonstrated strong diagnostic capability for radiation exposure and were positively correlated with radiation dose. Their expression levels were also closely associated with immune cell infiltration, including natural killer cells, plasma cell-like dendritic cells and regulatory T cells. Key regulatory interactions involved TFs (E2F1, TP53) and miRNAs (miR-145, miR-143), while associated genes included FEN1, REV1 and CDKN1A. Drugs linked to these genes included Quercetin and Hydroxyurea. In conclusion, the study identified five key genes with diagnostic potential for radiation exposure, positively correlated with radiation dose. These findings provide a foundation for radiation diagnosis and dose assessment, particularly in populations with later-stage diseases.