Abstract
OBJECTIVE: One of the biggest therapy challenges for nasopharyngeal cancer (NPC) is still radioresistance. The radioresistance in NPC is thought to be caused by cyclin D1 overexpression. The purpose of this study was to determine how cyclin D1 contributes to radiation resistance in NPC. METHODS: Adhering to the PRISMA guidelines, we systematically reviewed studies on cyclin D1-associated radioresistance in NPC from 2012 until 2023. From our search, 15 studies were included. RESULTS: Cyclin D1's role in radiotherapy resistance is elucidated through several mechanisms, notably SHP-1 and B-catenin. Overexpression of SHP-1 led to an increase in cyclin D1, a higher proportion of cells in the S-phase, and radioresistance. Conversely, inhibiting β-catenin and cyclin D1 expression enhances radiation sensitivity. CONCLUSION: In conclusion, Cyclin D1 has a strong correlation with radiation resistance; downregulation of the protein increases radiosensitivity, while overexpression of the protein promotes radioresistance.