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The nanoparticle-based electrochemical technology for early detection of cancer is an imjportant research topic in the area of biomedicine.This article introduces the concept of tumor marker and principle of electrochemical detection of the tumor marker.The applications of nanoparticles in electrochemical early detection of cancer are reviewed in detail.Finally,the prospected application of research is discussed.
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Objective To investigate the roles of P53/P21 during neuronal differentiation with a differentiated model of PC12 cells. Methods A new cell line PC12(P53/m175) was created by stable transfection of a retrovirus plasmid pBabe-P53/m175, which contains a dominant-negative P53 gene mutant. After NGF treatment, observing with phase-contrast microscopy, flow cytometric analysis and western blotting of P53 and P21 were performed. Results Expression of P53 and P21 was obviously increased in NGF-induced PC12 cells. The appearance of cell cycle G1 phase arrest paralleled the increased expressions of P53 and P21. The level of P21 protein did not change after treatment with NGF in PC12(P53/m175) cells and the extent of G1 phase arrest markedly decreased. However, we did find the normal neurite outgrowth in NGF-treated PC12(P53/m175) cells. Conclusion NGF-induced an increased protein levels of P53 and its transcriptional element, P21 is essential for cell cycle G1 phase arrest, but does not necessarily correlate with the neurite outgrowth of PC12 cells.
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<p><b>OBJECTIVE</b>To assess the atherogenicity of lipoprotein(a), the effect of the heterogeneity of lysine binding of apolipoprotein(a) [apo(a)], a plasminogen-like glycoprotein component on the proliferation of human arterial smooth muscle cells (SMCs).</p><p><b>METHODS</b>Both wild type (wt) Trp72 and mutant (mut) Trp72-->Arg forms of apo(a) kringle IV-10 were expressed by employing a GST-gene fusion system into E. coli. The proliferation of SMCs was determined by flow cytometry and MTT colorimetry. Enzyme-linked immunosorbent assay (ELISA) assay was used to detect the active form of transforming growth factor beta(1) (TGF-beta(1)).</p><p><b>RESULTS</b>Apo(a) wt-kringle IV-10 that has lysine binding properties possessed a growth-stimulating activity to SMCs on a dose-dependence manner by stimulating cells in the G(1)/G(0) phase of cell cycle to S and G(2)/M phase, and reduced significantly the amounts of endogenous active TGF-beta(1) in culture when compared with the control medium and the GST group (2.4 +/- 0.5 vs 8.6 +/- 1.6 and 9.1 +/- 1.7 ng/ml, P < 0.01). The growth-stimulating effect of apo(a) mut-kringle IV-10 deficient in lysine binding was negligible.</p><p><b>CONCLUSIONS</b>Apo(a) induces SMCs growth by inhibiting the activation of latent TGF-beta(1), an activity that may involve the ability of apo(a) kringle IV-10 to bind lysine. The mitogenic effect of apo(a) wt-kringle IV-10 on SMCs might play an active role in the atherogenic function of lipoprotein(a).</p>