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41.
Natural products are considered recently as one of the source for production of efficient therapeutical agents for breast cancer treatment. In this study, a sesquiterpene lactone, 13-O-acetylsolstitialin A (13ASA), isolated from Centaurea cyanus, showed cytotoxic activities against MCF-7 and MDA-MB-231 breast cancer cell lines using standard 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. To find the mechanism of action of cytotoxicity, annexin V/propidium iodide (PI) staining was performed for evaluation of apoptosis. This process was further confirmed by immunoblotting of anti- and proapoptotic, Bcl-2 and Bax, proteins. Cell cycle arrest was evaluated by measurement of fluorescence intensity of PI dye and further confirmed by immunoblotting of Cdk-4 and cyclin D1. Mitochondrial transmembrane potential (ΔΨm) and generation of reactive oxygen species (ROS) were measured using the JC-1 and DCFDA fluorescence probes, respectively. These experiments showed that 13ASA is a potent cytotoxic agent, which activates apoptosis-mediated cell death. In response to this compound, Bax/Bcl-2 ratio was noticeably increased in MCF-7 and MDA-MB-231 cells. Moreover, 13ASA induced cell cycle arrest at subG1 and G1 phases by decreasing protein levels of cyclin D1 and Cdk-4. It was done possibly through the decrease of ΔΨm and increase of ROS levels which induce apoptosis. In conclusion, this study mentioned that 13ASA inhibit the growth of MCF-7 and MDA-MB-231 breast cancer cell lines through the induction of cell cycle arrest, which triggers apoptotic pathways. 13ASA can be considered as a susceptible compound for further investigation in breast cancer study.  相似文献   
42.
Multiple modalities for lung cancer therapy have emerged in the past decade, whereas their clinical applications and survival-beneficiary is little known. Vaccination with dendritic cells (DCs) or DCs/cytokine-induced killer (CIK) cells has shown limited success in the treatment of patients with advanced non-small-cell lung cancer. To evaluate and overcome these limitations in further studies, in the present review, we sum up recent progress about DCs or DCs/CIKs-based approaches for preclinical and clinical trials in patients with lung cancer and discuss some of the limited therapeutic success. Moreover, this review highlights the need to focus future studies on the development of new approaches for successful immunotherapy in patients with lung cancer.  相似文献   
43.
International Journal of Peptide Research and Therapeutics - Immunoinformatics is a science that helps to create significant immunological information using bioinformatics softwares and...  相似文献   
44.
Hedgehog is an important morphogenic signal that directs pattern formation during embryogenesis, but its activity also remains present through adult life. It is now becoming increasingly clear that during the reproductive phase of life and beyond it continues to direct cell renewal (which is essential to combat the chronic environmental stress to which the body is constantly exposed) and counteracts vascular, osteolytic and sometimes oncological insults to the body. Conversely, down-regulation of hedgehog signalling is associated with ageing-related diseases such as type 2 diabetes, neurodegeneration, atherosclerosis and osteoporosis. Hence, in this essay we argue that hedgehog signalling is not only important at the start of life, but also constitutes an important anti-geriatric influence, and that enhanced understanding of its properties may contribute to developing rational strategies for healthy ageing and prevention of ageing-related diseases. Also watch the Video Abstract.  相似文献   
45.
The activities of arginase, glutamine synthetase (GS) and glutamate dehydrogenase (GDH) were studied in both moist chilled (5°C) and warm (27°C) incubated walnut (Juglans regia. L) kernels to asses whether the non-germinability of dormant kernels is associated with failure in amino acid metabolism. Warm-incubated kernels showed low germination (25%), whereas cold-stratified kernels displayed germination up to 61%. Arginase activity increased about twofold in imbibed kernels. It remained at a high level in cold-stratified kernels from mid-period of incubation onwards; however, in warm-incubated kernels the activity declined after an initial increase so that by 20 days, it was negligible. No significant differences in GS activity occurred between cold-stratified and warm-incubated kernels, but the activity of GDH was significantly more in kernels incubated at warm conditions. Thin-layer chromatographic separation of polyamines revealed greater ammonia, spermidine and an unknown polyamine accumulation in warm-incubated kernels. Thus, the declined rate of walnut kernel germination under warm conditions is mainly correlated with rapid inactivation of arginase, greater levels of ammonia and alterations in kernel polyamine composition. The enhanced activity of GDH in warm-incubated kernels implies that catabolic deamination of amino acids and their subsequent respiration is the favored pathway ongoing under warm conditions. This situation compromises germination-specific metabolism of amino acids which likely to operate better at lower temperatures during cold stratification of kernels.  相似文献   
46.
The MEK/ERK pathway is found to be important in regulating different biological processes such as proliferation, differentiation and survival in a wide variety of cells. However, its role in self‐renewal of haematopoietic stem cells is controversial and remains to be clarified. The aim of this study was to understand the role of MEK/ERK pathway in ex vivo expansion of mononuclear cells (MNCs) and purified CD34+ cells, both derived from human umbilical cord blood (hUCB). Based on our results, culturing the cells in the presence of an inhibitor of MEK/ERK pathway—PD0325901 (PD)—significantly reduces the expansion of CD34+ and CD34+ CD38? cells, while there is no change in the expression of stemness‐related genes (HOXB4, BMI1). Moreover, in vivo analysis demonstrates that PD reduces engraftment capacity of ex vivo expanded CD34+ cells. Notably, when ERK pathway is blocked in UCB‐MNCs, spontaneous erythroid differentiation is promoted, found in concomitant with increasing number of burst‐forming unit‐erythroid colony (BFU‐E) as well as enhancement of erythroid glycophorin‐A marker. These results are in total conformity with up‐regulation of some erythroid enhancer genes (TAL1, GATA2, LMO2) and down‐regulation of some erythroid repressor genes (JUN, PU1) as well. Taken together, our results support the idea that MEK/ERK pathway has a critical role in achieving the correct balance between self‐renewal and differentiation of UCB cells. Also, we suggest that inhibition of ERK signalling could likely be a new key for erythroid induction of UCB‐haematopoietic progenitor cells.  相似文献   
47.
microRNAs (miRNAs) are known as a large group of short noncoding RNAs, which structurally consist of 19–22 nucleotides in length and functionally act as one of the main regulators of gene expression in important biological and physiological contexts like cell growth, apoptosis, proliferation, differentiation, movement (cell motility), and angiogenesis as well as disease formation and progression importantly in cancer cell invasion, migration, and metastasis. Among these notable tiny molecules, many studies recently presented the important role of the miR-193 family comprising miR-193a-3p, miR-193a-5p, miR-193b-3p, and miR-193b-5p in health and disease biological processes by interaction with special targeting and signaling, which mainly contribute as a tumor suppressor. Therefore, in the present paper, we review the functional role of this miRNA family in both health and disease conditions focusing on various tumor developments, diagnoses, prognoses, and treatment.  相似文献   
48.
Caveolae are invaginated plasma membrane domains of 50–100 nm in diameter involved in many important physiological functions in eukaryotic cells. They are composed of different proteins, including the membrane-embedded caveolins and the peripheric cavins. Caveolin-1 has already been expressed in various expression systems (E. coli, insect cells, Toxoplasma gondii, cell-free system), generating intracellular caveolin-enriched vesicles in E. coli, insect cells and T. gondii. These systems helped to understand the protein insertion within the membrane and its oligomerization. There is still need for fundamental insights into the formation of specific domains on membrane, the deformation of a biological membrane driven by caveolin-1, the organization of a caveolar coat, and the requirement of specific lipids and proteins during the process. The aim of this study was to test whether the heterologously expressed caveolin-1β was able to induce the formation of intracellular vesicles within a Gram+ bacterium, Lactococcus lactis, since it displays a specific lipid composition different from E. coli and appears to emerge as a good alternative to E. coli for efficient overexpression of various membrane proteins. Recombinant bacteria transformed with the plasmid pNZ-HTC coding for the canine isoform of caveolin-1β were shown to produce caveolin-1β, in its functional oligomeric form, at a high expression level unexpected for an eukaryotic membrane protein. Electron microscopy revealed several intracellular vesicles from 30 to 60 nm, a size comparable to E. coli h-caveolae, beneath the plasma membrane of the overexpressing bacteria, showing that caveolin-1β is sufficient to induce membrane vesiculation. Immunolabelling studies showed antibodies on such neo-formed intracellular vesicles, but none on plasma membrane. Density gradient fractionation allowed the correlation between detection of oligomers on Western blot and appearance of vesicles measurable by DLS, showing the requirement of caveolin-1β oligomerization for vesicle formation. Lactococcus lactis cells can heterologously overexpress caveolin-1β, generating caveolin-1β enriched intracellular neo-formed vesicles. These vesicles might be useful for potential co-expression of membrane proteins of pharmaceutical interest for their simplified functional characterization.  相似文献   
49.
The possible association of angiotensin type 2 receptor (AT2R) − 1332 G:A polymorphism with susceptibility to preeclampsia was studied in 252 women consisted of 155 women with preeclampsia and 97 healthy pregnant women. Also, the interaction of this polymorphism with angiotensin type 1 receptor (AT1R) 1166 A:C, angiotensin converting enzyme insertion/deletion (ACE I/D) and also with matrix metalloproteinase-9 (MMP-9) − 1562 C:T polymorphism was investigated. The AT2R − 1332 G:A polymorphism was detected using PCR–RFLP method. Significantly higher frequencies of GG+GA genotype and G allele of AT2R were observed in mild (80.2%, p = 0.003 and 47.5%, p = 0.012, respectively) and severe (77.8%, p = 0.034 and 48.1%, p = 0.026, respectively) preeclampsia compared to controls (60.8% and 35.1%, respectively). The presence of G allele was associated with 1.69-fold increased risk of preeclampsia (p = 0.005). In severe preeclamptic women, systolic and diastolic blood pressures in the presence of GG+GA genotype were significantly higher compared to those in the presence of AA genotype. The concomitant presence of both alleles of AT2R G and AT1R C was associated with 1.3 times increased risk of mild preeclampsia (p = 0.03). There was an interaction between AT2R G and ACE D alleles that significantly increased the risk of mild and severe preeclampsia by 1.38- and 1.3-fold, respectively. Also, interaction between MMP-9 T and AT2R G alleles increased the risk of severe preeclampsia 1.39-fold (p = 0.028). Our study demonstrated that the G allele of AT2R − 1332 G:A polymorphism is associated with an increased risk of preeclampsia. Also, epistatic interaction of G allele and each allele of the AT1R C, ACE D and MMP-9 T was associated with the risk of preeclampsia. Our findings suggest that the renin–angiotensin system (RAS) variants and gene–gene interactions affect the risk of preeclampsia.  相似文献   
50.
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