Abstract 4799: The expression of nuclear factor-kB in human oral squamous cell carcinoma and its relationship with clinical factors

[Background] Nuclear factor-κB (NF-κB), a key transcription factor plays a major role in carcinogenesis, regulate many important signaling pathways involved in tumor progression. The overexpression of NF-κB in the nuclei has been reported to be a poorer prognostic factor in various malignancies. However, the prognostic value of NF-κB expression in patients with oral cancer is less understood. [Purpose] The aims of present study were to evaluate the expression of p65 protein, which is NF-κB subunits, in oral squamous cell carcinoma (OSCC) and to elucidate the relationships among the p65 expression, clinical stages, histological differentiation and classification of invasion mode. [Materials and Methods] Tissue specimens were obtains from 78 patients with OSCC after surgery or biopsy. Immunohistochemistry was used to assess the p65 subunit of NF-κB, using >10% nuclear staining-positive cells as a surrogate of activation. Human OSCC cell lines, B88, cells were used in this study. After B88 cells were inoculated into the tongue of nude mice, tumors and metastatic lymph nodes were cut off, and applied to immunohistochemical analysis of p65. [Results] Immunohistochemical analysis of 78 cases of OSCC showed that the expression of cytoplasmic p65 was detected in all OSCC and in 4/6 cases of epithelial dysplasia, but not in normal epithelial cells. 19 (24.3%) cases of 78 OSCC patients expressed nuclear p65 protein. There was no relationship between nuclear p65 expression and clinical stages, or classification of invasion mode. There were significant differences between nuclear p65 expression and histological differentiation or metastasis. Nuclear p65 expression of cancer cells in metastatic lymph nodes increased compared with cancer cells of primary sites. Although nuclear p65 expression of B88 cells tumor in the tongue was not almost detected, nuclear p65 expression of cancer cells in metastatic lymph nodes was increased. [Conclusions] These findings suggested that the expression of nuclear p65 in OSCC could be related to histological differentiation and metastasis. Citation Format: Tetsuya Tamatani, Natsumi Takamaru, Makoto Kinouchi, Nobuyuki Kuribayasi, Daisuke Uchida, Kenji Fujisawa, Hirokazu Nagai, Youji Miyamoto. The expression of nuclear factor-kB in human oral squamous cell carcinoma and its relationship with clinical factors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington,