125I radiation downregulates TRPV1 expression through miR‑1246 in neuroblastoma cells.

Iodine-125 (I-125) seed radiation applied around the celiac ganglion can relieve the refractory pain in pancreatic cancer. In an in vitro cell radiation model of human neuroblastoma cell lines, the impact of I-125 radiation on the expression of transient receptor potential vanilloid-1 (TRPV1) was investigated. The results indicated that the radiation delivering doses <2.13 Gy did not significantly affect cell growth, whereas the doses >3.12 Gy significantly reduced cell viability. The reduced TRPV1 mRNA level was dependent on the doses, while the reduced protein level occurred at lower doses (2.63 and 4.27 Gy), then returned to normal at an intermediate dose of 5.09 Gy, and decreased again at higher doses (5.91 and 6.73 Gy). The miRNA profiling at the dose of 2.63 Gy revealed 32 and 22 miRNAs that were significantly upregulated and downregulated, respectively. In addition, the upregulated miR-1246 target, regulated the expression of TRPV1, indicating that miR-1246 may be a new therapeutic target for pancreatic pain.