Background
Therapy-induced senescence plays an important role in the clinical treatment of tumors, which is positively correlated with the treatment response. However, senescent cells reshape tumor microenvironment and increase the risk of cancer recurrence. Regarded as hormones to regulate cell-to-cell communication, microRNA (miRNA) is highly sensitive to environmental stress. To understand the response of tumor cells to chemotherapeutic drugs, miRNAs in chemotherapy-induced senescent cells and their secreted extracellular vehicles (EVs) were detected and the miRNA profiles were analyzed, hoping to provide some thoughts for the evaluation of chemotherapy effect in clinical tumor treatment.
Conclusions
The expression profiles of miRNA in senescent neuroblastoma cells and extracellular vesicles were altered, and the differentially expressed miRNAs were mostly involved in cellular metabolic pathways. The information decryption can provide reference for clinical interpretation of the phenomenon of therapy-induced senescence.
Methods
Neuroblastoma cell line IMR32 was treated with low concentration of aurora kinase A (AURKA) inhibitor MLN8237 to establish a cell senescence model. RNAs were extracted from senescent cells and extracellular vesicles, and miRNA spectrum was investigated by small RNA deep sequencing.
Results
Thirteen miRNAs including miR-378b and miR-206 were significantly increased, whereas 32 miRNAs including miR-205-5p, miR-378d, and miR-378f were significantly decreased in the senescence cell group. In senescent cells secreted extracellular vesicles, there were 48 of up-regulated miRNAs including miR-205-5p and 9 of down-regulated miRNAs. Bioinformatics analysis revealed that these differentially expressed miRNAs in senescent cells may potentially regulate many common target genes which belong to the metabolic signaling pathway and transcriptional misregulation in cancer. Conclusions: The expression profiles of miRNA in senescent neuroblastoma cells and extracellular vesicles were altered, and the differentially expressed miRNAs were mostly involved in cellular metabolic pathways. The information decryption can provide reference for clinical interpretation of the phenomenon of therapy-induced senescence.