Abstract: PURPOSE: To investigate the influence of p75, ICD on anoikis resistance ability of tumor cells based on generation of an anoikis cell model, discuss the activation of related signaling pathways. METHODS: Immunohistochemistry was used to detect p75, ICD expression in lymph node metastatic, non-lymph node metastatic, primary specimens of oral squamous cell carcinoma. Western blot was used to detect the expression of p75, ICD in a pair of low-, high- metastatic potential OSCC cell lines. Poly-HEMA was used to pre-coat the cell culture dish in order to generate anoikis cell model. Over-expression of p75, ICD was conducted in tumor cells with plasmid transfection. Flow cytometry was used to detect apoptosis level of tumor cells after suspension culture. Laser scanning confocal microscopy analysis, Western blot were performed to detect the activation of related signal pathways of tumor cells in anoikis cell model. SPSS22.0software package was used for statistical analysis. RESULTS: The positive staining of p75NTR ICD in lymph node metastatic OSCC cells was located in the cytoplasm, while on the cytomembrane in non-lymph node metastatic OSCC. The expression of p75, ICD was much higher in HN-12, which was more metastatic as well, compared with HN-4. Larger sphere was formed in HN-12anoikis cell model than in HN-4, lower apoptosis level of HN-12in anoikis cell model was observed than in HN-4. NF-κB signaling was activated in HN-12anoikis cell model, while not in HN-4. CONCLUSIONS: Cellular localization of p75, ICD in tumor cells was related to cervical lymph node metastasis. Over expression of p75NTR ICD in tumor cells shows higher anoikis resistance; p75, ICD promotes anoikis resistance through activating NF-κB signaling

Key words: Oral squamous cell carcinoma, Anoikis, p75^NTR ICD, NF-κB