Identification of key genes associated with cell cycle in ER+ breast cancer by bioinformatic analysis

This study aims to screen crucial genes associated with cell cycle in ER+ breast cancer through analyzing TCGA-BRCA, GSE45827 and GSE42568 datasets. Based on the screening of the differentially expressed genes, pathway enrichment was performed by pathfindR. Then we found five shared enriched pathways existing across all datasets, including Cell cycle, Fanconi anemia pathway, MAPK signaling pathway, ErbB signaling pathway and Ras signaling pathway. Up-regulated genes associated with cell-cycle control system are more likely to be therapeutic targets for breast cancer treatment. We overlapped the up-regulated genes involved in cell-cycle regulation in each dataset, resulting in identification of the 16 key genes strongly connected to cell cycle. PPI was constructed and then hub genes were predicted, including BUB1B, BUB3, MCM4, MAD2L1, ESPL1, CDC7, PTTG1, TTK, CCND1 and CCNB2 . Expressions of the hub genes were associated with short relapse-free survival for ER+ breast cancer. Taken together, we identified the hub genes associated with cell cycle in ER+ breast cancer and they may be effective biomarkers and therapeutic targets.