Protection of p53 wild type cells from taxol by nutlin-3 in the combined lung cancer treatment

<p>Abstract</p> <p>Background</p> <p>Mutations within the tumor suppressor <it>TP53 </it>gene are one of the most common genetic alterations present at high frequency in human tumors and have been shown to be associated with resistance to radio-chemotherapy. The lack of the wild type <it>TP53 </it>gene in cancer cells could be exploited for therapeutic advantage using a sequence of two antagonistic drugs. The aim of this study was to selectively kill p53 deficient cells (FaDu and H1299) by taxol and to protect p53 wild type cells (A549) by the prior administration of nutlin-3 in comparison to certain known anticancer drugs (5-fluorouracil, camptothecin, roscovitine).</p> <p>Methods</p> <p>Cytotoxic and cytostatic properties of 5-fluorouracil, camptothecin, roscovitine and nutlin-3 administrating alone or in combination with taxol were investigated in vitro by flow cytometry.</p> <p>Results</p> <p>It was found that nutlin-3 induced growth arrest and protected A549 cells from taxol. FaDu and H1299 cells responded to the same treatments with mitotic arrest and massive apoptosis. Other compounds (5-fluorouracil, camptothecin and roscovitine) revealed weaker selectivity and elevated toxicity in comparison to nutlin-3.</p> <p>Conclusions</p> <p>We propose a therapeutic strategy protecting normal cells from taxol while increasing apoptosis selectively in p53-deficient cells using nutlin-3.</p

Improvement of Radiation-Mediated Immunosuppression of Human NSCLC Tumour Xenografts in a Nude Rat Model

Human tumour xenografts in a nude rat model have consistently been used as an essential part of preclinical studies for anticancer drugs activity in human. Commonly, these animals receive whole body irradiation to assure immunosuppression. But whole body dose delivery might be inhomogeneous and the resulting incomplete bone marrow depletion may modify tumour behaviour. To improve irradiation-mediated immunosuppression of human non-small cell lung cancer (NSCLC) xenografts in a nude rat model irradiation (2 + 2 Gy) from opposite sides of animals has been performed using a conventional X-ray tube. The described modification of whole body irradiation improves growth properties of human NSCLC xenografts in a nude rat model. The design of the whole body irradiation mediated immunosuppression described here for NSCLC xenografts may be useful for research applications involving other types of human tumours

Evaluation of Endothelial Cells Differentiated from Amniotic Fluid-Derived Stem Cells

Amniotic fluid holds great promise as a stem cell source, especially in neonatal applications where autologous cells can be isolated and used. This study examined chemical-mediated differentiation of amniotic fluid-derived stem cells (AFSC) into endothelial cells and verified the function of AFSC-derived endothelial cells (AFSC-EC). AFSC were isolated from amniotic fluid obtained from second trimester amnioreduction as part of therapeutic intervention from pregnancies affected with twin-twin transfusion syndrome. Undifferentiated AFSC were of normal karyotype with a subpopulation of cells positive for the embryonic stem cell marker SSEA4, hematopoietic stem cell marker c-kit, and mesenchymal stem cell markers CD29, CD44, CD73, CD90, and CD105. Additionally, these cells were negative for the endothelial marker CD31 and hematopoietic differentiation marker CD45. AFSC were cultured in endothelial growth media with concentrations of vascular endothelial growth factor (VEGF) ranging from 1 to 100 ng/mL. After 2 weeks, AFSC-EC expressed von Willebrand factor, endothelial nitric oxide synthase, CD31, VE-cadherin, and VEGF receptor 2. Additionally, the percentage of cells expressing CD31 was positively correlated with VEGF concentration up to 50 ng/mL, with no increase at higher concentrations. AFSC-EC showed a decrease in stem cells markers c-kit and SSEA4 and were morphologically similar to human umbilical vein endothelial cells (HUVEC). In functional assays, AFSC-EC formed networks and metabolized acetylated low-density lipoprotein, also characteristic of HUVEC. Nitrate levels for AFSC-EC, an indirect measure of nitric oxide synthesis, were significantly higher than undifferentiated controls and significantly lower than HUVEC. These results indicate that AFSC can differentiate into functional endothelial-like cells and may have the potential to provide vascularization for constructs used in regenerative medicine strategies

Praćenje metabolizma flavonoida u humanim stanicama na temelju fluorescencije izazvane interakcijom kvercetina s proteinima

Despite the wealth of information concerning biological effects of flavonoids, a systematic approach to analyzing the molecular targets is still lacking and, for this reason, a rational evaluation of the risks or benefits of flavonoid-containing foods or of possible pharmaceutical applications is difficult. We have exploited the property of quercetin to elicit fluorescence when bound to specific target proteins and assayed several flavonoids with different modifications (methylation, hydroxylation, glycosylation). Quercetin target proteins can be visualized in living cells, but in vital human leukaemia cells (HL-60) the fluorescence decreases rapidly after labelling, while metabolically inactive apoptotic cells retain the fluorescence. These cytological differences were apparent under the fluorescent microscope and were quantified using flow cytometry. Metabolic conversion of quercetin in vital cells was confirmed and quantified by HPLC analysis. While apoptotic cells still contained considerable amounts of quercetin, vital cells rapidly metabolized the flavonoid (e.g., by methylation or glycosylation). Biochemical results are consistent with the cytological observations and support the conclusion that quercetin becomes rapidly converted to non-fluorogenic metabolites in vital cells. Loss of fluorescence in vital cells allows convenient monitoring and quantifying of the dynamics of quercetin metabolism in human cells.Unatoč mnoštvu informacija koje se odnose na biološke učinke flavonoida, sustavni pristup analizi njihovih ciljnih molekula još uvijek nedostaje. Iz toga razloga vrlo je teško racionalno vrednovati opasnosti ili koristi koje donosi hrana koja sadrži flavonoide kao i njihovu moguću farmakološku primjenu. Iskoristili smo svojstvo kvercetina da izazove fluorescenciju kada se veže za specifične ciljne proteine i analizirali nekoliko različito modificiranih flavonoida (metilacija, hidroksilacija, glikozilacija). Ciljni proteini za koje se kvercetin veže u živim stanicama mogu se vizualizirati na temelju fluorescencije. U živim stanicama humane leukemije (HL-60) fluorescencija naglo pada nakon označavanja flavonoidima, dok metabolički inaktivne apoptotične stanice zadržavaju fluorescenciju. Te su citološke razlike jasno zapažene pod fluorescencijskim mikroskopom, a kvantificirane su pomoću protočne citometrije. Metabolička pretvorba kvercetina u živim stanicama potvr|ena je i kvantificirana pomoću HPLC analiza. Dok apoptotične stanice zadržavaju značajnu količinu kvercetina, žive ga stanice brzo metaboliziraju (npr. metilacijom ili glikozilacijom). Ti su biokemijski rezultati u skladu s citološkim promatranjima i podupiru zaključak da se kvercetin u živim stanicama brzo pretvara u nefluorogene metabolite. Gubitak fluorescencije u živim stanicama omogućava praćenje i kvantifikaciju dinamike metabolizma kvercetina u humanim stanicama

Effects of Sinusoidal Electromagnetic Field on Structure and Function of Different Kinds of Cell Lines

This study investigated that whether a 2 mT, 60 Hz, sinusoidal electromagnetic field (EMF) alters the structure and function of cells. This research compared the effects of EMF on four kinds of cell lines: hFOB 1.19 (fetal osteoblast), T/G HA-VSMC (aortic vascular smooth muscle cell), RPMI 7666 (B lymphoblast), and HCN-2 (cortical neuronal cell). Over 14 days, cells were exposed to EMF for 1, 3, or 6 hours per day (hrs/d). The results pointed to a cell type-specific reaction to EMF exposure. In addition, the cellular responses were dependent on duration of EMF exposure. In the present study, cell proliferation was the trait most sensitive to EMF. EMF treatment promoted growth of hFOB 1.19 and HCN-2 compared with control cells at 7 and 14 days of incubation. When the exposure time was 3 hrs/d, EMF enhanced the proliferation of RPMI 7666 but inhibited that of T/G HA-VSMC. On the other hand, the effects of EMF on cell cycle distribution, cell differentiation, and actin distribution were unclear. Furthermore, we hardly found any correlation between EMF exposure and gap junctional intercellular communication in hFOB 1.19. This study revealed that EMF might serve as a potential tool for manipulating cell proliferation

iASPP is over-expressed in human non-small cell lung cancer and regulates the proliferation of lung cancer cells through a p53 associated pathway

Background iASPP is a key inhibitor of tumour suppressor p53 and is found to be up-regulated in certain malignant conditions. The present study investigated the expression of iASPP in clinical lung cancer, a leading cancer type in the world, and the biological impact of this molecule on lung cancer cells. Methods iASPP protein levels in lung cancer tissues were evaluated using an immunohistochemical method. In vitro, iASPP gene expression was suppressed with a lentvirus-mediated shRNA method and the biological impact after knocking down iASSP on lung cancer cell lines was investigated in connection with the p53 expression status. Results We showed here that the expression of iASPP was significantly higher in lung cancer tissues compared with the adjacent normal tissues. iASPP shRNA treatment resulted in a down-regulation of iASPP in lung cancer cells. There was a subsequent reduction of cell proliferation of the two lung tumour cell lines A459 and 95D both of which had wild-type p53 expression. In contrast, reduction of iASPP in H1229 cells, a cell with little p53 expression, had no impact on its growth rate. Conclusions iASPP regulates the proliferation and motility of lung cancer cells. This effect is intimately associated with the p53 pathway. Together with the pattern of the over-expression in clinical lung cancers, it is concluded that iASPP plays an pivotal role in the progression of lung cancer and is a potential target for lung cancer therapy

Induction of Cancer Cell Death by Isoflavone: The Role of Multiple Signaling Pathways

Soy isoflavones have been documented as dietary nutrients broadly classified as “natural agents” which plays important roles in reducing the incidence of hormone-related cancers in Asian countries, and have shown inhibitory effects on cancer development and progression in vitro and in vivo, suggesting the cancer preventive or therapeutic activity of soy isoflavones against cancers. Emerging experimental evidence shows that isoflavones could induce cancer cell death by regulating multiple cellular signaling pathways including Akt, NF-κB, MAPK, Wnt, androgen receptor (AR), p53 and Notch signaling, all of which have been found to be deregulated in cancer cells. Therefore, homeostatic regulation of these important cellular signaling pathways by isoflavones could be useful for the activation of cell death signaling, which could result in the induction of apoptosis of both pre-cancerous and/or cancerous cells without affecting normal cells. In this article, we have attempted to summarize the current state-of-our-knowledge regarding the induction of cancer cell death pathways by isoflavones, which is believed to be mediated through the regulation of multiple cellular signaling pathways. The knowledge gained from this article will provide a comprehensive view on the molecular mechanism(s) by which soy isoflavones may exert their effects on the prevention of tumor progression and/or treatment of human malignancies, which would also aid in stimulating further in-depth mechanistic research and foster the initiation of novel clinical trials

CHANGE OF CELLULAR CYCLE AT RADIATION INJURY AND CARCINOGENESIS

The oncological patients have been examined. The experiments have been performed on 5,280 rats and 800 mice. The regularities of changing myelocaryocyte distribution in the rats according to the living cycle phases at radiation injury in the wide dose range and also at natural ageing of the animals have been revealed. The indication procedure of radiation injury with low dose powers and also the methods for diagnosis, forecasting efficiency, evaluation and treatment correction at some oncological diseases among people have been developed. The work results have been introducedAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

IV delivery of fluorescent beads

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