Correlation of NF-kappaB signal pathway with tumor metastasis of human head and neck squamous cell carcinoma.
BACKGROUND
Nuclear factor-kappa B (NF-kappaB) signaling constitutes a key event in the multistep process of carcinogenesis, progression and treatment in many cancer types. However, the significance of NF-kappaB pathway for complex and tissue-specific aspects of head and neck cancer progression, such as invasion and metastasis, is less understood.


METHODS
The expression of NF-kappaB p65 in squamous cell carcinoma of the head and neck (SCCHN) clinical specimens by immunohistochemistry. The role of NF-kappaB activity in head and neck squamous cell carcinoma was determined by western blot, reporter assay and EMSA analysis in vitro and metastasis assays in vivo in different metastatic potential tumor cells. Furthermore, the apoptosis rate and expression of metastasis-related protein such as MMP9 and VEGF were examined by Annexin V/PI staining and Western blot, respectively.


RESULTS
A higher level of active nuclear-localized NF-kappaB was observed in the metastatic SCCHN specimens group (p < 0.01). The NF-kappaB activities of SCCHN cell lines with different metastatic potentials were then determined and in excellent agreement with results found in SCCHN specimens, highly metastatic SCCHN cell lines expressed high level of NF-kappaB activity. The treatment of highly metastatic SCCHN cells with NF-kappaB inhibitors reduced the in vitro cell invasion capacity of the cells without affecting the apoptotic rate. Additionally, the NF-kappaB inhibitors significantly inhibited the experimental lung metastasis of Tb cells and lymph node metastasis of TL cells in nude mice. Furthermore, the expression of metastasis-related proteins, such as matrix metalloproteinase 9 and vascular endothelial growth factor, was inhibited by pyrrolidine dithiocarbonate.


CONCLUSIONS
This study suggests that NF-kappaB activity significantly contributes to tumor hematologic and lymphatic metastases and may aid in the development of early detection methods or therapies targeting non-conventional molecular targets.
Yan
Ming
M
Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.
Xu
Qin
Q
Zhang
Ping
P
Zhou
Xiao-jian
XJ
Zhang
Zhi-yuan
ZY
Chen
Wan-tao
WT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D024202:Electrophoretic Mobility Shift Assay; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008156:Luciferases / Q000378:metabolism; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000556:secondary*; D008207:Lymphatic Metastasis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009570:Nitriles / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013450:Sulfones / Q000494:pharmacology; D014407:Tumor Cells, Cultured
C416282:BAY 11-7085; D016328:NF-kappa B; D009570:Nitriles; D012333:RNA, Messenger; D013450:Sulfones; D008156:Luciferases