Ultra-fine zirconium carbide (ZrC) powder with nano-sized primary particles was synthesized by the carbothermal reduction method by using nano-sized and nano-sized graphite powders mixture. The synthesized ZrC powder was well dispersed after simple milling process. After heat-treatment at for 2 h under vacuum, ultra-fine ZrC powder agglomerates (average size, ) were facilely obtained with rounded particle shape and particle size of ~200 nm. Ultra-fine ZrC powder with an average particle size of 316 nm was obtained after ball milling process in a planetary mill for 30 minutes from the agglomerated ZrC powder.

Eukaryotic translation initiation factor 5A (eIF-5A) is essential for proliferation of eukaryotic cells, andwas identified as diagnotic marker in cervical intraepithelial neoplasia, cervical and endometrial cancer, but relatively little is known about thein vivo and in vitro expression patterns of eIF-5A in oral premalignant and malignant lesions mirror the expression levels observed in vitro with cells derived from normal oral mucosa, immortalized oral keratinocytes (IHOK) and primary and metastatic oral squamous cell carcinoma (OSCC). We used an oral squamous cell carcinoma (OSCC) progression model composed of cell lines and tissue specimens to characterize expression patterns by Western blotting and immunohistochemistry. eIF-5A and PCNA levels are elevated in IHOKand primary and metastatic OSCC cella as compatred to normal human oral keraitinocytes. eIF5A and PCNA expression was l imited to basal cells of normal oral mucosa. eIF-5A and PCNA expression is increased in dysplastic epithelium spreading to more superficial layers, and its expression levels correlated significantly with the degree of dysplasia. Well and moderately differentiated OSCC showed strong expression of eIF-5A and PCNA. These results suggest that upregulated expression of eIF-5A seems to be an important epigenetic alteration that accompanies oral carcinogenic progression, and eIF-5A could be used as an biomarker for oral premalignat lesion or squamous cell carcinoma

Considering the great potential of iron chelators at inhibiting the proliferation of tumor cells, in order to determine the molecular and biological basis for the effects of iron chelator in oral cancer, we investigated the effects of iron chelator, desferrioxamine (DFO), on the gene profiling analysis of immortalized human oral keratinocytes (IHOK), and oral cancer cells (HN12), using the cDNA microarray. We identified 46 clones cDNA exhibiting more than 2 fold overexpression in DFO treated IHOK and HN12 cells, and 94 cDNA reveal more than 2 fold down-regulated expression. Examination of gene expression that differs between DFO treated vs. control IHOK and HN12 cells apprear to be related to : cell cycle regulator, cell growth and apoptosis, signal transduction and stress. p21 for cell cell cycle factor was upregualted, and cyclin-cdk gene was decreased expression, so we observed cell cycle arrest in DFO treated IHOK and HN12 cells. In tumor growth, we have identified downregulation of hemidesmosomal protein (bullous pemphigoid antigen 1) and epiregulin expression in DFO treated IHOK and oral cancer cells. Signal transducers including mitogen-activated protein kinase-activated protein kinase 5, serine/thereonine kinase 6 were downregulated with DFO treated cells, suggesting the DFO regulates the p38 MAP kianse pathway in immortalized and maignant oral keratincytes. In conclusion, we have demonstrated the high-throughput utility of cDNA array hybridization in parallel to the gene expression analysis to identify genes that are expressed differentially in DFO treated with immortalized and malignant oral keratinocytes. The differentially expressed genes identified here should be informative in DFO-induced anti-cancer effects.