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.

Balloon angioplasty-induced neointimal hyperplasia remains a clinical problem that must be resolved. The bioactivities of the Crossostephium chinense extract (CCE) have demonstrated potential in preventing the progression of restenosis. The present study evaluated whether CCE can suppress balloon angioplasty-induced neointima formation and elucidated its possible pharmacological mechanisms. A rat model of carotid arterial balloon angioplasty was established to evaluate the inhibitory effect of CCEs on neointimal hyperplasia. Two cell lines, A10 vascular smooth muscle cells (VSMCs) and RAW264.7 macrophages, were used to investigate the potential regulatory activities and pharmacological mechanisms of CCEs in cell proliferation and migration and in inflammation. Our in vitro results indicated that CCE3, the ethanolic extract of C. chinense, exerted the strongest growth inhibitory and antimigratory effects on VSMCs. CCE3 blocked the activation of focal adhesion kinase, platelet-derived growth factor receptor-β (PDGFRB), and its downstream molecules (AKT and mTOR) and reduced the expression of matrix metalloproteinase-2. In addition, our findings revealed that CCE3 significantly increased the expression of miRNA-132, an inhibitory regulator of inflammation and restenosis, and suppressed the expression of inflammation-related molecules (inducible nitric oxide synthase, cyclooxygenase-2, interleukin- (IL-) 1β, and IL-6). Our in vivo study results indicated that balloon injury-induced neointimal hyperplasia was inhibited by CCE3. CCE3 could reduce neointima formation in balloon-injured arteries, and this effect may be partially attributed to the CCE3-induced suppression of PDGFRB-mediated downstream pathways and inflammation-related molecules.