[Mechanistic research progress on radiotherapy resistance of cancer stem cells]

Radiotherapy is an important treatment modality for tumors and is involved in the treatment course of more than 50% of cancer patients. However, resistance to ionizing radiation results in suboptimal radiotherapy efficacy and contributes to tumor recurrence and metastasis at later stages. With the increasing understanding of tumor pathogenesis, cancer stem cell (CSC), characterized by self-renewal capacity and differentiation potential, have attracted growing attention and play key roles in radiotherapy resistance, tumor progression, metastasis, immune evasion, and other processes. Mechanisms including the tumor microenvironment, DNA damage repair, and epithelial-mesenchymal transition (EMT) are critical drivers of CSC-mediated radiotherapy resistance. Reviewing the key pathways involved and identifying CSC-specific therapeutic targets may provide new insights for developing more efficient and less toxic radiotherapy strategies.