High-mobility group box 2 reflects exacerbated disease characteristics and poor prognosis in non-small cell lung cancer patients

Background High-mobility group box 2 (HMGB2) is considered as oncogene in non-small cell lung cancer (NSCLC), while its clinical implication is still unknown. This study aimed to explore the correlation of HMGB2 with clinicopathological characteristics and prognosis in NSCLC patients. Methods A total of 133 NSCLC patients who received radical excision were enrolled. HMGB2 expression in the tumor specimens and paired adjacent tissue specimens was determined by immunohistochemical assay (for protein expression) and reverse transcription quantitative polymerase chain reaction assay (for gene expression), respectively. Results HMGB2 protein expression was higher in tumor tissue compared with adjacent tissue, and it could distinguish tumor tissue from adjacent tissue (area under the curve (AUC): 0.775, 95%confidence interval (95%CI): 0.720-0.830). Meanwhile, tumor HMGB2 protein high expression correlated with lymph node (LYN) metastasis and advanced TNM stage. Additionally, tumor HMGB2 protein high expression associated with worse disease-free survival (DFS), while HMGB2 protein expression did not correlate with overall survival (OS). Besides, HMGB2 mRNA expression was raised in tumor tissue compared with adjacent tissue, and it had a good value in differentiating tumor tissue from adjacent tissue (AUC: 0.875, 95% CI: 0.834-0.915). Furthermore, tumor HMGB2 mRNA high expression correlated with higher Eastern Cooperative Oncology Group performance status score, LYN metastasis, and advanced TNM stage. Meanwhile, tumor HMGB2 mRNA high expression associated with shorter DFS and OS. Conclusion HMGB2 could be a biomarker that reflects disease features and prognosis of NSCLC, which is beneficial to improve clinical efficacy in NSCLC patients.