Iodine-125 seed brachytherapy inhibits non-small cell lung cancer by suppressing epithelial-mesenchymal transition.

PURPOSE: Metastatic non-small cell lung cancer (NSCLC) has posed a great clinical challenge with high mortality. Iodine-125 (I-125) seed brachytherapy has not been widely applied in clinic against NSCLC.

METHODS AND MATERIALS: Mice were injected with human H23 NSCLC cells to establish a mouse xenograft model, which received I-125 seed implantation. The curative effect, pathological impairments, and survival rate of mice were investigated. Changes in the expression levels of epithelial-mesenchymal transition (EMT) markers, including N-cadherin, E-cadherin, and vimentin, in the xenograft tumors were analyzed using reverse transcription polymerase chain reaction and Western blot.

RESULTS: The tumor volume and pathological effect were reduced by I-125 seed implant. I-125 seed implant also significantly improved survival rate of the model mice. Expression patterns of N-cadherin, E-cadherin, and vimentin were reversed in I-125 seed-implanted mice in comparison with control mice, indicating suppressed EMT.

CONCLUSIONS: I-125 seed brachytherapy significantly inhibits NSCLC by suppressing EMT in a mouse model.