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Proliferation Cell Nuclear Antigen (proliferation + cell_nuclear_antigen)
Selected AbstractsChromatin assembly factor-1 (CAF-1)-mediated regulation of cell proliferation and DNA repair: a link with the biological behaviour of squamous cell carcinoma of the tongue?HISTOPATHOLOGY, Issue 7 2007S Staibano Aims:, Squamous cell carcinoma (SCC) of the tongue shows aggressive behaviour and a poor prognosis. Clinicopathological parameters fail to provide reliable prognostic information, so the search continues for new molecular markers for this tumour. Chromatin assembly factor-1 (CAF-1) plays a major role in chromatin assembly during cell replication and DNA repair and has been proposed as a new proliferation marker. The aim of this study was to investigate its expression in SCC of the tongue. Methods and results:, The immunohistochemical expression of the p60 and p150 subunits of CAF-1 were evaluated in a series of SCCs of the tongue. The findings were correlated with the expression of proliferation cell nuclear antigen (PCNA) and patients' clinicopathological and follow-up data. CAF-1/p60 was expressed in all the tumours, whereas CAF-1/p150 was down-regulated in a number of cases. Overexpression of CAF-1/p60 and down-regulation of CAF-1/p150 identified SCCs with poor outcome, in addition to the classical prognostic parameters. Conclusions:, Simultaneous CAF-1-mediated deregulation of cell proliferation and DNA repair takes place in aggressive SCC of the tongue. Therefore, the evaluation of CAF-1 expression may be a valuable tool for evaluation of the biological behaviour of these tumours. This may be relevant to the introduction of improved follow-up protocols and/or alternative therapeutic regimens. [source] Expression of Mina53, a product of a Myc target gene in mouse testisINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2006MAKOTO TSUNEOKA Summary Recently we have identified a novel gene mina53 (mina), which is a direct transcriptional target of oncoprotein Myc. Mina53 protein was shown to be highly expressed in tumour cells and to play a role in cell proliferation. Here we report the expression of Mina53 in mouse testis, which contains proliferating cells and expresses many cancer-related genes. Immunohistochemical studies by using newly produced monoclonal antibody to Mina53 showed that Mina53 was expressed in the nuclei of spermatogonia. Mina53 was also expressed in meiotic prophase cells such as preleptotene, leptotene and zygotene, and weakly in early pachytene spermatocytes, but was absent in late pachytene spermatocytes, spermatids and mature sperm. The expression pattern of Mina53 was quite similar to that of proliferation cell nuclear antigen (PCNA). Using experimental cryptorchid testis, it was found that Mina53 was highly expressed in undifferentiated spermatogonia, which were PCNA-positive. These results suggest that Mina53 is prominently expressed in proliferating, undifferentiated spermatogonia, and plays a role in cell proliferation from the spermatogonial stage to the meiotic prophase in spermatogenesis, but not in meiotic divisions per se. [source] Morphological and molecular changes in denture-supporting tissues under persistent mechanical stress in ratsJOURNAL OF ORAL REHABILITATION, Issue 12 2008M. TSURUOKA Summary, The purpose of this study was to determine the effects of mechanical compression on the palatal mucosa using an experimental palatal base. The palatal base was either pressed onto (stress group) or not pressed onto (fit group) rat palatal mucosa. Blood flow was measured and the animals were sacrificed 6,72 h later for analysis. The expression of heat shock protein 70 (HSP70), vascular endothelial growth factor (VEGF) and proliferation cell nuclear antigen (PCNA) was characterized by immunohistochemical staining. For morphometric analysis, connective tissues were divided into bone side and epithelial side tissues. The ratio of PCNA-positive cells (PCNA score) was calculated, and the expressions of mRNA encoding HSP70 and VEGF was evaluated. Whereas blood flow in the stress group showed ischaemia, none was found in the fit group. Proliferation cell nuclear antigen scores on the bone side were higher than on the epithelial side in the stress group (P < 0·05). Heat shock protein 70- and VEGF-positive cells were observed under compression conditions, particularly in the periosteum. In the stress group, the expressions of mRNA encoding HSP70 and VEGF were highest at 12 h (P < 0·05). These results suggest that mechanical compression of the palatal plate induces ischaemia, and that cells in the underlying denture-supporting tissue, which includes the periosteum, synthesize HSP70 and VEGF to maintain homeostasis under these conditions. [source] Heparin Coating of Small-Caliber Decellularized Xenografts Reduces Macrophage Infiltration and Intimal HyperplasiaARTIFICIAL ORGANS, Issue 6 2009Wei-Wei Cai Abstract Small-caliber decellularized xenografts with surface heparin coating are known to reduce in vivo thrombogenicity. This study was performed to examine whether heparin coating on the small-caliber decellularized xenografts would reduce macrophage infiltration and intimal hyperplasia. In a rabbit model of bilateral carotid implantation, each of the animals (n = 18) received a heparin-coated decellularized xenograft from a canine carotid artery on one side and a nonheparin-coated one on the other side. These experiments were terminated respectively at 1 week (n = 6), 3 weeks (n = 6), and 12 weeks (n = 6). Results showed that, compared with the nonheparin-coated grafts, the heparin-coated grafts had significantly less macrophage infiltration 1 week after implantation, identified by the mouse antirabbit macrophage antibody (RAM11)-positive cells on the vascular wall, covering all the proximal, middle, and distal parts of the grafts (P < 0.01). Moreover, the heparin-coated grafts also showed less deposition of proliferation cell nuclear antigen (PCNA)-positive cells on the vascular wall, indicating less cell proliferation, which was significant not only at 1 week (P < 0.01) but also at 12 weeks (P < 0.01). Intimal hyperplasia, measured by the intimal : media (I : M) ratio, was found similar in both groups at 1 and 3 weeks. However, the I : M ratio was significantly lower in the heparin-coated group than in the nonheparin-coated group at 12 weeks, especially in the proximal anastomosis area (0.76 ± 0.12 vs. 0.345 ± 0.06, P < 0.01). Heparin coating of small-caliber decellularized xenografts is associated with an early reduction of macrophage infiltration and intimal hyperplasia in a rabbit model of bilateral carotid artery implantation for 12 weeks. Thus, heparin coating appears to deliver not only the antithrombogeneity but also the antiproliferative property for small-caliber decellularized xenografts. [source] | ||||||||||