Diverse CBX family members as potential prognostic biomarkers in non-small-cell lung cancer

Chromobox (CBX) family members are vital epigenetic regulators that repress the transcription of target genes through chromatin modification. Several studies have investigated the role of CBX family members in cancer. However, the function and prognostic value of diverse CBX family members in non-small-cell lung cancer remain largely unknown. In this study, we reveal that CBX family members are overexpressed in non-small-cell lung cancer tissue compared with normal lung tissue, with the exception of CBX6. Kaplan-Meier analysis demonstrated that high expressions of CBX1 and CBX3 are correlated with overall survival, disease-specific survival, disease-free interval, and progression-free interval for patients with lung adenocarcinoma (LUAD). Furthermore, regression model analysis suggests that CBX3 may be suitable as an independent prediction factor for overall survival and progression-free interval in patients with LUAD. In addition, CBX3 mRNA expression was found to be associated with tumor diameter and lymph node metastasis. Gene enrichment analysis suggests that CBX3 is involved in the cell cycle and P53 signaling pathways. Aberrant expression of CBX3 in LUAD is correlated with DNA copy number alteration. In summary, our data imply that CBX3 plays an important role in the promotion of LUAD and may thus have potential as a prognostic biomarker and molecular therapeutic target for the disease.