RNF11 confers chemotherapy sensitivity to tumor cells by regulating the ubiquitination of KU80 and the cell cycle.

BACKGROUND

Ring finger protein 11 (RNF11) is integral to cell signal transduction and transcription factor regulation and is strongly connected to the beginning and progression of malignant tumors. However, the core mechanisms of RNF11 remain unknown to date. This study highlights the significant function of RNF11 in the DNA damage response.

METHODS

After the CRISPR-Cas9 gene knockout of RNF11, HCT116 cells were transfected, and cell viability assays were performed to evaluate the response of tumor cells to the chemotherapy drugs after RNF11 deletion. The interaction of RNF11 with its binding proteins and its ubiquitination mechanism, along with the recruitment of KU80 to chromatin, were subsequently evaluated. RNF11 was revealed to participate in the regulation of the cell cycle and apoptosis. An HCT116 xenograft tumor model was used to validate the in vivo sensitivity of tumors to 5-FU, revealing that RNF11 is essential for regulating the responsiveness of tumor cells to chemotherapy.

RESULTS

RNF11 modulates KU80 expression and participates in cell cycle regulation. The elimination of RNF11 results in the accumulation of KU80 at the DNA damage sites, induces G1 phase cell cycle arrest, and increases sensitivity to the chemotherapy drugs. Mechanistically, RNF11 regulates KU80 expression through a direct interaction and facilitates its ubiquitination while modulating apoptosis and the cell cycle, thereby participating in the cellular damage response. Furthermore, high RNF11 expression is associated with poor prognosis in patients with cancer, while RNF11 deletion impedes tumor progression and enhances the sensitivity of the xenografts to 5-FU treatment. These findings demonstrate that RNF11 is involved in the clinical tumor treatment processes and could be a target for cancer treatment.

CONCLUSION

RNF11 binds with KU80, facilitates its ubiquitination, supports DNA damage repair, preserves genomic stability, and enhances the chemotherapy response in tumor cells.