In addition, the correlation in the expression levels of Annexin A1 and its associated proteins S100A9 and Vimentin in different NPC cell types were evaluated; Annexin A1 /S100A9/Vimentin complex in NPC cells was detected by co-immunoprecipitation and Western blot analysis, and the effects of Annexin A1 modulation on S100A9 and Vimentin expression, as well as in vitro invasion ability of NPC cells were determined. Here, S100A9 is linked to nasopharyngeal carcinoma.