Fibulin‐3 is associated with tumour progression and a poor prognosis in nasopharyngeal carcinomas and inhibits cell migration and invasion via suppressed AKT activity

• Published in: The Journal of pathology 2010-12, Vol.222 (4), p.367-379
• Main Authors: Hwang, Chung‐Feng, Chien, Chih‐Yen, Huang, Shun‐Cheng, Yin, Yu‐Fang, Huang, Chao‐Cheng, Fang, Fu‐Min, Tsai, Hsin‐Ting, Su, Li‐Jen, Chen, Chang‐Han
• Format: Article
• Language: English
• Subjects: 1-Phosphatidylinositol 3-kinase; AKT protein; Biological and medical sciences; biomarkers; Biomarkers, Tumor - metabolism; Cell migration; Cell Movement - physiology; Disease Progression; DNA Methylation; DNA, Neoplasm - genetics; Down-Regulation; Extracellular Matrix Proteins - metabolism; Extracellular Matrix Proteins - physiology; Female; fibulin-3; Gene Knockdown Techniques; Humans; invasion; Investigative techniques, diagnostic techniques (general aspects); Lymph; Male; Medical sciences; Metastases; Middle Aged; migration; Molecular modelling; Mortality; Nasopharyngeal carcinoma; Nasopharyngeal Neoplasms - diagnosis; Nasopharyngeal Neoplasms - metabolism; Nasopharyngeal Neoplasms - pathology; Neoplasm Invasiveness; Neoplasm Proteins - metabolism; Neoplasm Staging; Otorhinolaryngology. Stomatology; p-AKT; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Polymerase Chain Reaction - methods; Prognosis; Promoter Regions, Genetic; Proto-Oncogene Proteins c-akt - metabolism; RNA, Small Interfering - genetics; siRNA; Survival Analysis; Tumor Cells, Cultured; Tumors; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology
• ISSN: 0022-3417; 1096-9896
• DOI: 10.1002/path.2776

Nasopharyngeal carcinoma (NPC) is known for its highly metastatic character. Recent advances in diagnosis and treatment have not improved the high mortality rate that is attributable to early metastasis. Although several biomarkers correlate with metastasis and prognosis, the molecular mechanisms of NPC development and progression remain unclear. We demonstrate comprehensively that fibulin‐3 is down‐regulated in NPC. Loss of fibulin‐3 expression is significantly correlated with advanced tumour and lymph node‐metastasis stages, and indicates a poor 5‐year survival rate. Functionally, fibulin‐3 has the ability to suppress cell migration and invasion in NPC cancer cells by decreasing the activity of phospho‐AKT. Conversely, its depletion by fibulin‐3‐mediated siRNAs may elevate phospho‐AKT activity and significantly enhance the ability of NPC cancer cells to migrate and invade. Consistent with this negative association between fibulin‐3 and phospho‐AKT, their expression levels are inversely correlated in NPC specimens by immunohistochemical analysis. Thus, lower fibulin‐3 expression is an important indicator of poor survival. It may also contribute to the development of new therapeutic strategies to block the PI3K/AKT pathway in NPC cancer cells. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.