• Journal of Life Science
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• v.22 no.11
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• pp.1552-1557
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• 2012

It has been reported that pipernonaline isolated from Piper longum Linn. has a wide biochemical and pharmacological effect, including antitumor activity in prostate cancer PC-3 cells. However, its mechanism and expression pattern of many genes involved in biological functions are not clearly understood. To perform the gene expression study in PC-3 cells treated with pipernonaline, a cDNA microarray chip composed of 44,000 human cDNA probes was used. As a result, cell cycle-related genes, apoptosis-related genes, and cell proliferation/growth-related genes have been identified in gene ontology of the DAVID database. These results suggest that pipernonaline has antitumor activity by regulating the expression pattern of genes involved in biological signaling pathway in prostate cancer PC-3 cells. Further, additional analysis of these microarray data can be a useful tool to identify the mechanism and discovery of novel genes in cancer therapy.

• Molecules and Cells
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• v.38 no.11
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• pp.966-974
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• 2015

Despite the presence of toll like receptor (TLR) expression in conventional $TCR{\alpha}{\beta}$ T cells, the direct role of TLR signaling via myeloid differentiation factor 88 (MyD88) within T lymphocytes on graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect after allogeneic stem cell transplantation (allo-SCT) remains unknown. In the allo-SCT model of C57BL/6 ($H-2^b$) ${\rightarrow}$ B6D2F1 ($H-2^{b/d}$), recipients received transplants of wild type (WT) T-cell-depleted (TCD) bone marrow (BM) and splenic T cells from either WT or MyD88 deficient (MyD88KO) donors. Host-type ($H-2^d$) P815 mastocytoma or L1210 leukemia cells were injected either subcutaneously or intravenously to generate a GVHD/GVL model. Allogeneic recipients of MyD88KO T cells demonstrated a greater tumor growth without attenuation of GVHD severity. Moreover, GVHD-induced GVL effect, caused by increasing the conditioning intensity was also not observed in the recipients of MyD88KO T cells. In vitro, the absence of MyD88 in T cells resulted in defective cytolytic activity to tumor targets with reduced ability to produce IFN-${\gamma}$ or granzyme B, which are known to critical for the GVL effect. However, donor T cell expansion with effector and memory T-cell differentiation were more enhanced in GVHD hosts of MyD88KO T cells. Recipients of MyD88KO T cells experienced greater expansion of Foxp3- and IL4-expressing T cells with reduced INF-${\gamma}$ producing T cells in the spleen and tumor-draining lymph nodes early after transplantation. Taken together, these results highlight a differential role for MyD88 deficiency on donor T-cells, with decreased GVL effect without attenuation of the GVHD severity after experimental allo-SCT.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.1
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• pp.9-14
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• 2003

Recent studies indicated that cancer cells become resistant to ionizing radiation (IR) and chemotherapy drugs by enhanced DNA repair of the lesions. Therefore, it is expected to increase the killing of cancer cells and reduce drug resistance by inhibiting DNA repair pathways that tumor cells rely on to escape chemotherapy. There are a number of key human DNA repair pathways which depend on multimeric polypeptide activities. For example, Ku heterodimer regulatory DNA binding subunits (Ku70/Ku80) on binding to double strand DNA breaks (DSBs) are able to interact with 470-kDa DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and are essential for DNA-dependent protein kinase (DNA-PK) activity. It has been known that DNA-PK is an important factor for DNA repair and also is a sensor-transmitting damage signal to downstream targets, leading to cell cycles arrest. Our ultimate goal is to develop a treatment of breast tumors by targeting proteins involved in damage-signaling pathway and/or DNA repair. This would greatly facilitate tumor cell cytotoxic activity and programmed cell death through DNA damaging drug treatment. Therefore, we designed a domain of Ku80 mutants that binds to Ku70 but not DNA end binding activity and used the peptide in co-therapy strategy to see whether the targeted inhibition of DNA-PK activity sensitized breast cancer cells to irradiation or chemotherapy drug. We observed that the synthesized peptide (HNI-38) prevented DNA-PKcs from binding to Ku70/Ku80, thus resulting in inactivation of DNA-PK activity. Consequently, the peptide treated cells exhibited poor to no DNA repair, and became highly sensitive to IR or chemotherapy drugs, and the growth of breast cancer cells was inhibited. Additionally, the results obtained in the present study also support the physiological role of resistance of cancer cells to IR or chemotherapy.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.349-361
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• 2010

In this review, the current knowledge of the carbon metabolism and global carbon regulation in Corynebacterium glutamicum are summarized. C. gluamicum has phosphotransferase system (PTS) for the utilization of sucrose, glucose, and fructose. C. glutamicum does not show any preference for glucose when various sugars or organic acids are present with glucose, and thus cometabolizes glucose with other sugars or organic acids. The molecular mechanism of global carbon regulation such as carbon catabolite repression (CCR) in C. glutamicum is quite different to that in Gram-negative or low-GC Gram-positive bacteria. GlxR (glyoxylate bypass regulator) in C. glutamicum is the cyclic AMP receptor protein (CRP) homologue of E. coli. GlxR has been reported to regulate genes involved in not only glyoxylate bypass, but also central carbon metabolism and CCR including glycolysis, gluconeogenesis, and tricarboxylic acid (TCA) cycle. Therefore, GlxR has been suggested as a global transcriptional regulator for the regulation of diverse physiological processes as well as carbon metabolism. Adenylate cyclase of C. glutamicum is a membrane protein belonging to class III adenylate cyclases, thus it could possibly be a sensor for some external signal, thereby modulating cAMP level in response to environmental stimuli. In addition to GlxR, three additional transcriptional regulators like RamB, RamA, and SugR are also involved in regulating the expression of many genes of carbon metabolism. Finally, recent approaches for constructing new pathways for the utilization of new carbon sources, and strategies for enhancing amino acid production through genetic modification of carbon metabolism or regulatory network are described.

• Journal of Gastric Cancer
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• v.6 no.1
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• pp.25-30
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• 2006

Purpose: The EphB2 receptor, a member of the receptor tyrosine kinase family, is a target gene of the Wnt signaling pathway and may achieve a tumor suppressor function through regulation of cell growth and migration. Our aim was to determine whether an altered expression of EphB2 might be associated with gastric cancer development and, if so, to determine to which pathologic parameter it is linked. Materials and Methods: For the construction of the gastric cancer tissue microarray, 83 paraffin-embedded tissues containing gastric cancer areas were cored 3 times and transferred to the recipient master block. The expression patterns of EphB2 were examined on tissue microarray slides by using immunohistochemistry and were compared using pathologic parameters, including histological type, depth of invasion, lymph node metastatsis, and peritoneal dissemination. Results: The EphB2 protein was expressed in the normal gastric mucosal epithelium, especially in the bottom of the mucosa. We found loss of EphB2 expression in 30 (36.1%) of the 83 gastric cancer tissues. Statistically, loss of EphB2 expression was more common in gastric cancer with lymph-node metastasis. There was no significant correlation between EphB2 expression and depth of invasion, histologic type, or peritoneal dissemination. Conclusion: Our findings suggest that loss of EphB2 expression may represent a critical step in gastric carcinogenesis.

• KSBB Journal
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• v.28 no.1
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• pp.1-6
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• 2013

Curcumin has diverse anticancer activities that lead to tumor growth inhibition of cancer cells and induction of apoptosis. Curcumin is involved in the regulation of multiple genes via transcription factors including NF-${\kappa}B$, STATs, AP1, and SP. Notch signaling plays critical roles in maintaining the balance between cell proliferation, differentiation and apoptosis, and thereby may contribute to the development of various cancers involving breast cancer. This study was to investigate the effects of curcumin on Notch1 gene expression and to explore the underlying mechanism. Here, we found that curcumin decreased the levels of Notch1 mRNA and protein in MDA-MB-231 human breast cancer cells, along with the downregulation of Sp family genes (Sp1, Sp2, Sp3, and Sp4). The repressive effect of curcumin on Notch1 gene transcription was confirmed by performing Notch1 promoter-driven reporter assay and three Sp-binding sites were identified on Notch1 promoter that may act as curcumin-respose elements. Moreover, treatment with mitramycin A, a specific Sp inhibitor, decreased the levels of Notch1 mRNA and protein in human breast cancer cells. Taken together, our results indicate that Notch1 gene expression is downregulated by curcumin, at least in part, through the suppression of Sp family, which may lead to apoptosis in human breast cancer cells.

• Journal of Life Science
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• v.24 no.9
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• pp.927-934
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• 2014

Sanguinarine, a benzophenanthridine alkaloid originally derived from the root of Sanguinaria canadensis, has been shown to possess antimicrobial, antioxidant, and anti-cancer properties. Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known to induce apoptosis in cancer cells, but not most normal cells and has shown efficacy in a phase 2 clinical trial, development of resistance to TRAIL by tumor cells is a major roadblock. Our previous study indicated that treatment with TRAIL in combination with subtoxic concentrations of sanguinarine sensitized TRAIL-mediated apoptosis in TRAIL-resistant human gastric carcinoma AGS cells; however, the detailed mechanisms are not fully understood. In this study, we show that sanguinarine sensitizes AGS cells to TRAIL-mediated apoptosis as detected by MTT assay, agarose gel electrophoresis, chromatin condensation and flow cytometry analysis. Combined treatment with sanguinarine and TRAIL effectively induced expression of death receptor (DR) 5 but did not affect expression of DR4 and mitogen activated protein kinases signaling molecules. Moreover, the combined treatment with sanguinarine and TRAIL increased the generation of reactive oxygen species (ROS); however, N-acetylcysteine, ROS scavenger, significantly recovered growth inhibition induced by the combined treatment. Taken together, our results indicate that sanguinarine can potentiate TRAIL-mediated apoptosis through upregulation of DR5 expression and ROS generation.

• Molecules and Cells
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• v.40 no.8
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• pp.567-576
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• 2017

The $Na^+/H^+$ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular $Na^+$ and the extrusion of intracellular $H^+$. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent $Na^+/H^+-exchange$ inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a $sub-G_0/G_1$ peak, and a $G_2/M$ phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, $p-ATM^{Ser1981}$, $p-ATR^{Ser428}$, $p-CHK1^{Ser345}$, and $p-CHK2^{Thr68}$, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acidtolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.

• Reproductive and Developmental Biology
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• v.37 no.4
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• pp.233-245
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• 2013

Muscle satellite cell (SC) is responsible for postnatal muscle growth, repair, and regeneration. Satellite cell is an important source of multi-potent stem cell process and differentiation into adipogenic, myogenic, and osteoblastogenic. The objective of this study was to identify alter of transcriptome during differentiation in porcine satellite cell and to elevated transcriptome at different stages of postnatal development to gain insight into the differences in differentiated PSC. We used RNA-seq technique to investigate the transcriptomes during differentiation in pig muscle. Sequence reads were obtained from Illumina HiSeq2000. Differentially expressed genes (DEG) were detected by EdgeR. Gene ontology (GO) terms are powerful tool for unification among representation genes or products. In study of GO biological terms, functional annotation clustering involved in cell cycle, apoptosis, extracellular matrix, phosphorylation, proteolysis, and cell signaling in differences stage. Taken together, these results would be contributed to a better understanding of muscle biology and processes underlying differentiation. Our results suggest that the source of DEGs could be better understanding of the mechanism of muscle differentiation and transdifferentiation.

• Mycobiology
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• v.45 no.4
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• pp.297-311
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• 2017

Saprolegniasis is one of the most devastating oomycete diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated oomycete belongs to the member of S. parasitica, supported by its typical features including cotton-like mycelium, zoospores and phylogenetic analysis with internal transcribed spacer region. Pathogenicity of isolated S. parasitica was developed in embryo, juvenile, and adult zebrafish as a disease model. Host-pathogen interaction in adult zebrafish was investigated at transcriptional level. Upon infection with S. parasitica, pathogen/antigen recognition and signaling (TLR2, TLR4b, TLR5b, NOD1, and major histocompatibility complex class I), pro/anti-inflammatory cytokines (interleukin $[IL]-1{\beta}$, tumor necrosis factor ${\alpha}$, IL-6, IL-8, interferon ${\gamma}$, IL-12, and IL-10), matrix metalloproteinase (MMP9 and MMP13), cell surface molecules ($CD8^+$ and $CD4^+$) and antioxidant enzymes (superoxide dismutase, catalase) related genes were differentially modulated at 3- and 12-hr post infection. As an anti-Saprolegnia agent, plant based lawsone was applied to investigate on the susceptibility of S. parasitica showing the minimum inhibitory concentration and percentage inhibition of radial growth as $200{\mu}g/mL$ and 31.8%, respectively. Moreover, natural lawsone changed the membrane permeability of S. parasitica mycelium and caused irreversible damage and disintegration to the cellular membranes of S. parasitica. Transcriptional responses of the genes of S. parasitica mycelium exposed to lawsone were altered, indicating that lawsone could be a potential anti-S. parasitica agent for controlling S. parasitica infection.