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Background: Lysyl oxidase (LOX) is a copper-dependent enzyme that cross-links collagen and elastin in the extracellular matrix. LOX overexpressed in various tumors. The manner in which LOX affects tumor growth remains controversial., Methods: Chemical treatment and gene transfection were used to induce LOX overexpression or inhibition in cell lines SAS and SVEC4-10. LOX mRNA, protein, and activity were confirmed before tube formation assay and tumorigenesis. The microvessels in the tumor section were detected by immunostaining CD31-positive endothelial cells., Results: LOX overexpression and copper induction of LOX activity increased SVEC4-10 tube formation. LOX silencing and β-aminopropionitrile inhibition of LOX activity had opposite effects. LOX overexpression increased proliferation and proliferating cell nuclear antigen expression. High LOX expression clones increased tumor size in a tumorigenesis model. The microvascular numbers were higher in LOX overexpression tumors than in control tumors., Conclusion: LOX can induce cell proliferation and angiogenesis in oral squamous cell carcinoma., (Copyright © 2012 Wiley Periodicals, Inc.)

Abstract: Bacterial adhesion and colonization are considered to play key roles in the pathogenesis of peri-implant disease, which is an inflammatory process leading the destruction of both soft and hard tissue around a Titanium (Ti) implant. The osseointegration of Ti implants is influenced by their composition and surface treatment. Zirconia (ZrO2) coatings have been shown to improve implant osseointegration in various biomedical fields, including orthopedic devices and dental implants. This study used a twin-gun magnetron sputtering system to deposit ZrO2–Sliver (Ag) and ZrO2–Copper (Cu) coatings on biograde pure-Ti implant materials. The effects of Ag and Cu on the antibacterial properties of the coated Ti samples were investigated using Staphylococcus aureus (S. aureus) and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), which are found frequently in implant-associated infections. The in vitro antibacterial analyses employed a fluorescence staining method using SYTO9 and bacterial-viability tests on agar plates. Incorporating Ag and Cu into ZrO2 changed the structure of crystalline ZrO2, and the nanostructures of the resulting ZrO2–Ag and ZrO2–Cu coatings were found to be correlated with the antibacterial performance. The adherence of S. aureus and A. actinomycetemcomitans was less for ZrO2 samples with a small doping of Cu than for uncoated Ti. The ZrO2–Ag coating with an Ag content of 10.6at.%, which showed hydrophobicity, exhibited the lowest bacterial retention and viability of S. aureus and A. actinomycetemcomitans. The results suggest that ZrO2–Ag and ZrO2–Cu coatings improve the antibacterial performance relative to pure-Ti implant materials. [Copyright &y& Elsevier]