• Nutrition Research and Practice
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• v.10 no.4
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• pp.377-384
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• 2016

BACKGROUND/OBJECTIVES: Resveratrol, a natural polyphenol, has multiple functions in cellular responses including apoptosis, survival, and differentiation. It also participates in the regulation of inflammatory response and oxidative stress. MicroRNA-Let-7A (miR-Let7A), known as a tumor suppressor miRNA, was recently reported to play a crucial role in both inflammation and apoptosis. Therefore, we examined involvement of miR-Let7A in the modulation of inflammation and cell survival/apoptosis regulated by resveratrol. MATERIALS/METHODS: mRNA expression of pro-/anti-inflammatory cytokines and sirtuin 1 (SIRT1), and protein expression of apoptosis signal-regulating kinase 1 (ASK1), p-ASK1, and caspase-3 and cleaved caspase-3 were measured, and cell viability and Hoechst/PI staining for apoptosis were observed in Lipopolysaccharide (LPS)-stimulated human THP-1 macrophages with the treatment of resveratrol and/or miR-Let7A overexpression. RESULTS: Pre-treatment with resveratrol ($25-200{\mu}M$) resulted in significant recovery of the reduced cell viabilities under LPS-induced inflammatory condition and in markedly increased expression of miR-Let7A in non-stimulated or LPS-stimulated cells. Increased mRNA levels of tumor necrosis $factor-{\alpha}$ and interleukin (IL)-6 induced by LPS were significantly attenuated, and decreased levels of IL-10 and brain-derived neurotrophic factor were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. Decreased expression of IL-4 mRNA by LPS stimulation was also significantly increased by miR-Let7A overexpression co-treated with resveratrol. In addition, decreased SIRT1 mRNA levels, and increased p-ASK1 levels and PI-positive cells by LPS stimulation were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. CONCLUSIONS: miR-Let7A may be involved in the inflammatory response and cell survival/apoptosis modulated by resveratrol in human THP-1 macrophages.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.239-244
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• 2014

Several recent studies have showed that the n-myc downstream regulated gene 2 (NDRG2) is a new tumor suppressor gene, and that it plays an important role in tumor suppression in several cancers or cancer cell lines. However, few studies focused on its function in neuroblastoma cells. In the present investigation, we demonstrated that NDRG2 overexpression inhibited their proliferation. Using a cDNA microarray, we found that overexpression of NDRG2 inhibited the expression of cysteine-rich protein 61 (CYR61), a proliferation related gene. From our research, CYR61 may partially hinder NDRG2-mediated inhibition of cell proliferation. Overexpression of NDRG2 resulted in accumulation of cells in the G1 phase, which was accompanied by upregulation of p21 and p27 and downregulation of CDK4 and cyclin D1. Taken together, these data indicate that NDRG2 inhibits the proliferation of neuroblastoma cells partially through suppression of CYR61. Our findings offer novel insights into the physiological roles of NDRG2 in neuroblastoma cell proliferation, and NDRG2 may prove to be effective candidate for the treatment of children with neuroblastoma.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.572-578
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• 2016

Communication between endothelial cells (ECs) and smooth muscle cells (SMCs) via miR-143/145 clusters is vital to vascular stability. Previous research demonstrates that miR-143/145 released from ECs can regulate SMC proliferation and migration. In addition, a recent study has found that SMCs also have the capability of manipulating EC function via miR-143/145. In the present study, we artificially increased the expression of miR-143/145 in ECs, to mimic a similar change caused by miR-143/145 released by SMCs, and applied untargeted metabolomics analysis, aimed at investigating the consequential effect of miR-143/145 overexpression. Our results showed that miR-143/145 overexpression alters the levels of metabolites involved in energy production, DNA methylation, and oxidative stress. These changed metabolites indicate that metabolic pathways, such as the SAM cycle and TCA cycle, exhibit significant differences from the norm with miR-143/145 overexpression.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.68-74
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• 2009

We have previously demonstrated that overexpression and characterization of Brassica rapa type-l metallothionein gene (BrMT1) in Arabidopsis which showed enhanced resistance to cadmium and ROS. Here, we present the consistent study of our previous report about BrMTs. BrMT3 expressing DTY167 cells showed resistance to Zn and Pb as well as Cd. Thus, we have developed the BrMT3 overexpression Arabidopsis to enhance capacity for metal stresses. Successful expression and localization were achieved using the rubisco transit peptides of RbcS-BrMT3-GFP protein, which was confirmed by western blot analysis with the GFP antibody and green fluorescence signal from the chloroplast. BrMT3 overexpression Arabidopsis plants exhibited a higher resistance to cadmium compared to control plants. This result indicates that BrMT3 would be applicable to the development of plants with enhanced resistance against heavy metal stresses.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1425-1430
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• 2012

Cyclin L2 is a novel member of the cyclin family, recently implicated in the regulation of cell cycle progression and/or transcriptional regulation. The present study was undertaken to investigate the effects of overexpression on tumor cell growth and chemosensitivity in human gastric cells in vitro. Cyclin L2 was transfected into human gastric cancer cell line BCG823 and expressed with a mammalian expression vector pcDNA3.1. The effects and mechanisms of cyclin L2 on cell growth, cell cycling and apoptosis were studied. Compared to control vectors, overexpression of cyclin L2 inhibited the growth of BCG823 cells and enhance their chemosensitivity to fluorouracil, docetaxel and cisplatin. The anti-proliferative effects of cyclin L2 could be due to G0/G1 arrest and apoptosis. Cyclin L2 induced G0/G1 arrest and apoptosis involved upregulation of caspase-3 and down regulation Bcl-2 and survivin. The results indicated that overexpression of cyclin L2 protein may promote efficient growth inhibition and enhance chemosensitivity to chemotherapeutic agents in human gastric cancer cells by inducing G0/G1 cell cycle arrest and apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6415-6421
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• 2012

Background: Canine mammary gland tumors (CMGTs) are the most common tumor found in bitches. Changes in HER-2/neu genes in human breast cancer (HBC) lead to decrease in disease-free survival (DFS) and overall survival rate (OSR). Previous studies have demonstrated that the biological behavior of malignant mammary gland tumors (MMGTs) is similar to that of HBC. The present study aimed at evaluating the relationship between overexpression of HER-2/neu and clinicopathological features in MMGTs to represent a model of prognostic factors for HBC. Materials and Method: The clinicopathological data of 35 MMGTs were obtained. Immunohistochemical staining with HER-2, Ki-67 and CD34 markers was conducted with sections from paraffin-embedded blocks. According to standard protocols, histological type, grade, margin status, lymphovascular invasion (LVI), HER-2/neu score, proliferation rate and microvessel density (MVD) of tumors were determined and the association of HER-2/neu overexpression with these parameters was assessed statistically. Results: The IHC results showed that 12 (34.3%) cases were HER-2/neu positive. Statistical analyses indicated a significant relationship between HER-2 positivity and tumor grade (p=0.043), which also was demonstrated with cancer stage (p=0.035), tumor margin involvement (p=0.016), proliferation index (p=0.001) and MVD (p=0.001); however, there was no statistical relationship between LVI and tumor size. Overexpression of the HER-2/neu gene in MMGTs results in similar biological behavior as that of HBC; as a result, these tumors have can be considered to have important similarities in clinicopathological characteristics. Conclusions: MMGTs can be regarded as an HBC animal model. Further studies in this field would result in new treatments that could be beneficial for both dogs and humans.

• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.72-77
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• 2009

Here, we demonstrate that the overexpression of the GroELS chaperone system, which assists the folding of intracellular proteins and prevents aggregation of its biological targets, can enhance the thermotolerance of Escherichia coli strains and facilitate the production of recombinant protein under thermal stress. The overexpression of GroELS led to an about 2-fold higher growth rate of E. coli XL-1 blue than control at $45^{\circ}C$ and induced the growth of the strain even at $50^{\circ}C$, although the growth was not sustained in the second-round culture. The effect of GroELS overexpression was also effective on other E. coli strains such as JM109, $DH5{\alpha}$, and BL21. Finally, we have shown that coexpression of GroELS allows us to produce recombinant protein even at $50^{\circ}C$, a temperature at which the protein production based on E. coli is not efficient. This study indicates that the employment of the GroELS overexpression system can expand the range of environmental conditions for E. coli.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.332-340
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• 2016

Seed size traits are controlled by multiple genes in crops and determine grain yield, quality and appearance. However, the molecular mechanisms controlling the size of plant seeds remain unclear. We performed functional analysis of BrPATL4 encoding Sec14-like protein to determine the genetic architecture of seed size, shape and their association analyses. We used 60 $T_3$ transgenic rice lines to evaluate seed length, seed width and seed height as seed size traits, and the ratios of these values as seed shape traits. Pleiotropic effects on general architecture included small seed size, erect panicles, decreased grain weight, reduced plant height and increased sterility, which are common to other mutants deficient in gibberellic acid (GA) biosynthesis. To test whether BrPATL4 overexpression is deleterious for GA signal transduction, we compared the relative expression of GA related gene and the growth rate of second leaf sheath supplied with exogenous $GA_3$. Overexpression of BrPATL4 did not affect GA biosynthesis or signaling pathway, with the same response shown under GA treatment compared to the wild type. However, the causal genes for the small seed phenotype (D1, SRS1, and SRS5) and the erection of panicles showed significantly decreased levels in mRNA accumulation compared to the wild type. These results suggest that the overexpression of BrPATL4 can control seed size through the suppression of those genes related to seed size regulation. Although the molecular function of BrPATL4 is not clear for small seed and erect panicles of BrPALT4 overexpression line, this study provides some clues about the genetic engineering of rice seed architecture.

• Molecules and Cells
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• v.28 no.2
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• pp.93-98
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• 2009

A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.81-90
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• 2004

Sialic acid containing glycosphingolipids (gangliosides) have been implicated in the regulation of various biological phenomena such as atherosclerosis. Recent report suggeststhat exogenously supplied disialoganglioside (GD3) serves a dual role in vascular smooth muscle cells (VSMC) proliferation and apoptosis. However, the role of the GD3 synthase gene in VSMC responses has not yet been elucidated. To determine whether a ganglioside is able to modulate VSMC growth. the effect of overexpression of the GD3 synthase gene on DNA synthesis was examined. The results show that the overexpression of this gene has a potent inhibitory effect on DNA synthesis and ERK phosphorylation in cultured VSMC in the presence of PDGF. The suppression of the GD3 synthase gene was correlated with the down-regulation of cyclinE/CDK2. the up-regulation of the CDK inhibitor p21 and blocking of the p27 inhibition,whereas up-regulation of p53 as the result of GD3 synthase gene expression was not observed. Consistently, blockade of GD3 function with anti-GD3 antibody reversed VSMC proliferation and cell cycle proteins. The expression of the CD3 synthase gene also led to the inhibition of TNF--induced matrix metalloproteinase-9 (MMP-9) expression in VSMC as determined by zymography and immunoblot. Furthermore, GD3 synthase gene expression strongly decreased MMP-9 promoteractivlty in response to TNF-. This inhibition was characterized by the down-regulation of MMP-9,which was Iranscriptionally regulated at NF-B and activation protein-1 (AP-1) sites in the MMP-9promoter Finally, the overexpression of MMP-9 in GD3 synthase transfectant cells rescued VSMC proliferation. However MMP-2 overexpression was not affected the cell proliferation. These findings suggest that the fl13 synthase gene represents a physiological modulator of VSMC responses that may contribute to plaque instability in atherosclerosis.