The main problem of radiotherapy is that some cancer cells acquire radioresistance after radiation. Remodeled tumor microenvironment (TME) is an inevitable consequence following irradiation, however, its cardinal gene expression remains unknown. We aimed to find out screen and validate surrogate genes of TME alteration related to radiation resistance (RR) to improve the poor prognosis of head and neck squamous cell carcinoma (HNSCC), which demands radiotherapy. NM23A was one of the surrogate markers to be related to RR and partly translocated into nucleus when upregulated.

NM23A is a powerful candidate for radiation-resistant related gene products screened by both proteomics and cDNA platform array, and validated in vitro by IF and ex vivo by IHC. With overexpression of NM23A, nuclear translocation could be a biomarker to predict biological locoregional failure followed by radiotherapy in head and neck SCC.

Results (I) : NM23a translocation to nucleus radiation-treated cell lines.

Results (II) : IHC of NM23 in HNSCC FFPE tissue samples obtained from locoregional failure followed by radiotherapy.