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Survivin, an inhibitor of apoptosis protein and a cell cycle regulator, has been detected in the majority of human cancers. Five splice variants (survivin, survivin-2α, survivin-2B, survivin-3B, and survivin-ΔEx3) have been identified; their expressions have been investigated here. By means of RT real-time PCR and immunohistochemistry, we have evaluated survivin isoform expressions at both mRNA and protein levels in human normal oral tissue, precancerous lesions, and oral squamous cell carcinoma (OSCC). Their correlations with the pathological findings have also been analyzed. Expression levels of all survivin transcript variants were markedly elevated in OSCC when compared to normal tissues. One-way analysis of variance (ANOVA) revealed highly significant up-regulation of survivin ( P = 0.001), survivin-ΔEx3 ( P = 0.001) and survivin-2B ( P = 0.004), whereas survivin-3B showed a minor increase in OSCC compared to normal mucosa. Our findings suggest that survivin isoforms deregulation may have significant implications in tumor aggressiveness and prognosis. [ABSTRACT FROM AUTHOR]

Summary: Ascorbic acid (AA), also known as Vitamin C, is a cofactor required for the function of several hydroxylases. It is not synthesised in humans and has to be provided by diet. Its absence is responsible for scurvy, a condition related to the defective synthesis of collagen by the reduced function of prolylhydroxylase. AA is also a risk factor for periodontal disease. Recently, it has been shown that AA induces embryonic stem cells to differentiate into osteoblasts. The mechanism by which AA sustains pre-osteoblast proliferation and commitment is mediated through the synthesis of collagen type I, interaction with alpha2- and beta1-integrin, activation of the mitogen-activated protein kinase pathway, and phosphorylation of osteoblast-specific transcription factors. However, the multifunctional role of AA is not fully elucidated. MC3T3-E1 mouse calvaria-derived cell line is a well-defined in vitro model of pre-osteoblast differentiation, and AA is essential for the proliferation and differentiation of MC3T3-E1. By using DNA micro-arrays containing 15,000 genes, we identified several genes in MC3T3-E1 cultured with AA for 24h whose expression was significantly up or downregulated. The differentially expressed genes covered a broad range of functional activities: (1) cell growth; (2) metabolism; (3) morphogenesis; (4) cell death; (5) cell communication. The data reported are, to our knowledge, the first genetic portrait of early stage stimulation of pre-osteoblasts by AA, and may be relevant to better understand the molecular mechanism of pre-osteoblast proliferation and commitment. Elucidation of the molecular mechanism has important clinical implications because it may facilitate the correct use of AA to accelerate bone regeneration. [Copyright &y& Elsevier]

Zirconium oxide ceramics have outstanding mechanical properties, a high biocompatibility and a high resistance to scratching. Expression profiling by DNA microarray is a molecular technology that allows the analysis of gene expression in a cell system. By using DNA microarrays containing 19,200 genes, we identified in osteoblast-like cells line (MG-63) cultured on zirconium oxide discs (Cercon, Degussa Dental, Hanau, Germany) several genes whose expression was significantly up or down-regulated. The differentially expressed genes cover a broad range of functional activities: (a) immunity, (b) vesicular transport and (c) cell cycle regulation. It was also possible to detect some genes whose function is unknown. The data reported are, to our knowledge, the first genetic portrait of a zirconium oxide surface. They can be relevant to better understand the molecular mechanism of biocompatibility and as a model for comparing other materials. [Copyright &y& Elsevier]