• Archives of Pharmacal Research
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• v.21 no.5
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• pp.521-526
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• 1998

The physicochmical properties of recombinant hepatitis B surface antigen (r-HBsAg), which was expressed in C127 mammalian cell were studied. Using roller bottle culture in DMEM supplemented with fetal bovine serum, 10-15 mg/L of r-HBsAg was produced with about 31% of purification yield. The purity of r-HBsAg by HPLC was 99.8% and electron microscopic examination showed homogeneous spherical particle with 22 nm in diameter, a morphological characteristic of HBsAg. The density of r-HBsAg by CsCI density gradient method was 1.19g/ml and the isoelectric point by Mono $P^{TM}$ HR 5/20 column was 4.6. The analysis of subunit protein pattern using SDS-PAGE followed by scanning densitometry gave 81.3% of S protein and 18.7% of pre-S protein. fluorophore-assisted-carbohydrate-electrophoresis analysis showed the relative amount of carbohydrate to protein was 1.7% and it smajr component was N-acetyl glucosamine, which was about 39% of total carbohydrate. The relative amount of lipid to protein determined by vanillin phosphoric acid method was 32.5% and its major component was phospholipid, which was about 70% of total lipid. The physicochemical properties of C127 mammalian cell-derved r-HBsAg are similar to those of p-HBsAg, suggesting that the r-HBsAg can be used in developing a new preventive vaccine against hepatitis B.

• Molecules and Cells
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• v.45 no.10
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• pp.718-728
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• 2022

Splicing factor B subunit 4 (SF3B4), a component of the U2-pre-mRNA spliceosomal complex, contributes to tumorigenesis in several types of tumors. However, the oncogenic potential of SF3B4 in lung cancer has not yet been determined. The in vivo expression profiles of SF3B4 in non-small cell lung cancer (NSCLC) from publicly available data revealed a significant increase in SF3B4 expression in tumor tissues compared to that in normal tissues. The impact of SF3B4 deletion on the growth of NSCLC cells was determined using a siRNA strategy in A549 lung adenocarcinoma cells. SF3B4 silencing resulted in marked retardation of the A549 cell proliferation, accompanied by the accumulation of cells at the G0/G1 phase and increased expression of p27, p21, and p53. Double knockdown of SF3B4 and p53 resulted in the restoration of p21 expression and partial recovery of cell proliferation, indicating that the p53/p21 axis is involved, at least in part, in the SF3B4-mediated regulation of A549 cell proliferation. We also provided ubiquitination factor E4B (UBE4B) is essential for p53 accumulation after SF3B4 depletion based on followings. First, co-immunoprecipitation showed that SF3B4 interacts with UBE4B. Furthermore, UBE4B levels were decreased by SF3B4 depletion. UBE4B depletion, in turn, reproduced the outcome of SF3B4 depletion, including reduction of polyubiquitinated p53 levels, subsequent induction of p53/p21 and p27, and proliferation retardation. Collectively, our findings indicate the important role of SF3B4 in the regulation of A549 cell proliferation through the UBE4B/p53/p21 axis and p27, implicating the therapeutic strategies for NSCLC targeting SF3B4 and UBE4B.

• The Korean Journal of Zoology
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• v.28 no.3
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• pp.166-178
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• 1985

In order to express hepatitis B surface antigen $(HB_sAg)$ containing pre-surface antigen region in mammalian calls, 2.7 kb DNA fragment containing pre-surface region-$HB_sAg$ gene poly(A) addition site of HBV genome was cloned into simian virus 40(SV 40) based chimeric vector pSVOB. 2.7 kb DNA fragment was derived from pHBVD 107 containing tandem copies of the HBV genome in a head-to-tail arrangement by Bgl II digestion. Construction of the vector pSVOE involved the incorporation of SV40 sequences spanning the viral origin of replication and 72 bp repeats (enhancer) into a pBR 322 derivative lacking sequences which inhibit replication in mammalian cells. Bam HI linker was inserted at the Pvu II site in the proximity of SV40 late promoter of pSVOE and named as pSVOB. To construct the recombinant plasmid pSVBS, pHBVD 107 was digested with Bgl II to isolate 2.7kb DNA fragment and the fragment was ligated into the Bam HI site of pSVOB by ligation. Preliminary result showed that the recombinant plasmid pSVBS produced $HB_sAg$ in the monkey cell producing large T antigen (COS cell).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.10
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• pp.601-609
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• 2014

This paper proposes a resource allocation scheme suitable for D2D communications in multi-cell environment. In order to solve the inter-cell interference, the proposed scheme allocates the pre-assigned resource group and shares the information with neighbor cells. This paper also proposes a power control scheme for D2D communication to enhance the cell throughput. By the simulation results, the average SINR of the cellular uplink and D2D communication link are mostly higher than 10 dB when the proposed scheme is applied. On the other hand, with the inter-cell non-coordinated resource allocation scheme, the average SINR of the D2D communication link are decreased by 0 dB. In addition, the proposed scheme can enhance the cell throughput up to 8 % compared with the inter-cell non-coordinated resource allocation scheme.

• IMMUNE NETWORK
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• v.14 no.6
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• pp.265-276
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• 2014

The interactions between B7 molecules and CD28-family receptors are crucial in the regulation of adaptive cellular immunity. In cancer, the aberrant expression of co-inhibitory B7 molecules has been attributed to reduced anti-tumor immunity and cancer immune evasion, prompting the development of cancer therapeutics that can restore T cell function. Murine tumor models have provided significant support for the targeting of multiple immune checkpoints involving CTLA-4, PD-1, ICOS, B7-H3 and B7-H4 during tumor growth, and clinical studies investigating the therapeutic effects of CTLA-4 and PD-1 blockade have shown exceptionally promising results in patients with advanced melanoma and other cancers. The expression pattern of co-inhibitory B7 ligands in the tumor microenvironment has also been largely correlated with poor patient prognosis, and recent evidence suggests that the presence of several B7 molecules may predict the responsiveness of immunotherapies that rely on pre-existing tumor-associated immune responses. While monotherapies blocking T cell co-inhibition have beneficial effects in reducing tumor burden, combinatorial immunotherapy targeting multiple immune checkpoints involved in various stages of the anti-tumor response has led to the most substantial impact on tumor reduction. In this review, we will examine the contributions of B7- and CD28-family members in the context of cancer development, and discuss the implications of current human findings in cancer immunotherapy.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.67-71
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• 1988

It has been observed that white loght can suppress both cell growth and protein secretion in Baker's yeast. This effect was explored in batch liquid fermentations. Possible applications of this phenomenon are (a) use as a tool for pre-concentrating excreted enzymes prior to subsequent purification and (b) an engineering variable for regulation yeast fermentations.

• Journal of Life Science
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• v.30 no.6
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• pp.501-512
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• 2020

Sasa quelpaertensis Nakai leaf has been used as a folk medicine for the treatment of gastric ulcer, dipsosis, and hematemesis based on its anti-inflammatory, antipyretic, and diuretic characteristics. We have previously reported the procedure for deriving a phytochemical-rich extract (PRE) from S. quelpaertensis and how PRE and its ethyl acetate fraction (EPRE) exhibits an anticancer effect by inducing apoptosis in various gastric cancer cells. To explore the molecular targets involved in this apoptosis, we investigated the mRNA and microRNA profiles of EPRE-treated SNU-16 human gastric cancer cells. In total, 2,875 differentially expressed genes were identified by RNA sequencing, and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the EPRE-modulated genes are associated with apoptosis, mitogen-activated protein kinase, inflammatory response, tumor necrosis factor signaling, and cancer pathways. Subsequently, protein-protein interaction network analysis confirmed interactions among genes associated with cell death and apoptosis, and 27 differentially expressed microRNAs were identified by further sequencing. Here, GO and KEGG pathway analysis revealed that EPRE modified the expression of microRNAs associated with the cell cycle and cell death, as well as signaling of tropomyosin-receptor-kinase receptor, transforming growth factor-b, nuclear factor kB, and cancer pathways. Taken together, these results provide insight into the mechanisms underlying the anticancer effect of EPRE.

• Korean Journal of Pharmacognosy
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• v.45 no.4
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• pp.282-287
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• 2014

The ORI2 (3-[3,4-dihydroxyphenyl]acrylic acid 1-[3,4-dihydroxyphenyl]-2-methoxycarbonylethyl ester) was purified from the extract of Isodon excisus. We confirmed the antiviral effect of ORI2 in a coxsackievirus-induced pancreatitis model. Coxsackievirus B4 (CVB4) is a common cause of pancreatitis and may be reason of the type-1 diabetes. Anti-enteroviral compounds were screened by HeLa cell survival assay. Purified natural compounds were added to HeLa cells cultured 96-well plates after $10^4PFU/ml$ CVB4 pre-incubation for 30 min. ORI2 significantly improved HeLa cell survival in a dose-dependent manner. In addition, ORI2 (1 mM) treatment was dramatically decreased virus protease 2A induced eIF4G-I cleavage and viral VP1 capsid protein production. HeLa cell virus titers and viral RNA replication were significantly decreased in ORI2-treatment in a dose dependent manner (1 mM~0.001 mM). These results demonstrate that ORI2 has a strong antiviral effect. It was significantly decreased virus replication. ORI2 may be developed as a potential therapeutic agent for CVB4.

• Biomedical Science Letters
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• v.20 no.1
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• pp.32-38
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• 2014

Potassium cyanate (KOCN) that is known as an inducer of the protein carbamylation is an inorganic compound and is the conjugate based of cyanic acid (HOCN). Based on these studies, we confirmed that KOCN induces the apoptosis of the human colorectal cancer cell line, HCT 116 cells, by various mitochondrial pathways. To investigate other mechanisms of KOCN-mediated apoptosis, in the present study, we examined KOCN-induced cytokines production in HCT 116 cells and identified the intracellular signaling pathway in these processes. We first demonstrated that KOCN considerably increased the cell apoptosis via intracellular $Ca^{2+}$ signaling, mitochondrial dysfunction and ROS production. And then we examined TNF-${\alpha}$ and IL-$1{\beta}$ levels mediated by KOCN in HCT 116 cells. Although IL-$1{\beta}$ was not involved in KOCN-mediated HCT 116 cell apoptosis, the release of TNF-${\alpha}$ was mediated by KOCN in HCT 116 cells via NF-${\kappa}B$ activation. Apoptosis was also enhanced by incubation with supernatants from HCT 116 cells after KOCN treatment and this effect was partially reduced by BAY 11-7085 pre-treated supernatant. Taken together, our results indicate that KOCN-induced apoptosis in HCT 116 cells is dependent on the releases of TNF-${\alpha}$ and the increased factors and that the mechanism involves the activation of NF-${\kappa}B$.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.959-960
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• 2009