• BMB Reports
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• v.49 no.4
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• pp.238-243
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• 2016

The efficacy of anticancer drugs depends on a variety of signaling pathways, which can be positively or negatively regulated. In this study, we show that SETDB1 HMTase is down-regulated at the transcriptional level by several anticancer drugs, due to its inherent instability. Using RNA sequence analysis, we identified FosB as being regulated by SETDB1 during anticancer drug therapy. FosB expression was increased by treatment with doxorubicin, taxol and siSETDB1. Moreover, FosB was associated with an increased rate of proliferation. Combinatory transfection of siFosB and siSETDB1 was slightly increased compared to transfection of siFosB. Furthermore, FosB was regulated by multiple kinase pathways. ChIP analysis showed that SETDB1 and H3K9me3 interact with a specific region of the FosB promoter. These results suggest that SETDB1-mediated FosB expression is a common molecular phenomenon, and might be a novel pathway responsible for the increase in cell proliferation that frequently occurs during anticancer drug therapy.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.5
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• pp.391-396
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• 2014

Although interleukin-11 (IL-11) has been reported to be elevated in hypoxic tumors and has been associated with a poor prognosis in various cancers, little is known about its precise role in promoting metastasis in hypoxic tumors. In the present study, the molecular mechanism underlying the effects of IL-11 on MDA-MB-231 breast cancer cells migration and invasion in relation to metastasis under hypoxic conditions has been defined. Inhibition of IL-11 expression or function using small interfering RNA (siRNA) or a neutralizing antibody attenuated hypoxic MDA-MB-231 breast cancer cell migration and invasion through down-regulation of matrix metalloproteinases (MMPs) and activation of epithelial-to-mesenchymal transition (EMT) related gene expression. In addition, hypoxia-induced IL-11 increased STAT3 phosphorylation and STAT3 knockdown suppressed hypoxic MDA-MB-231 breast cancer cell invasion due to reduced MMP levels and reprogrammed EMT-related gene expression. These results suggest that one of the hypoxic metastasis pathways and the regulation of this pathway could be a potential target for novel cancer therapeutics.

• BMB Reports
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• v.47 no.4
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• pp.209-214
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• 2014

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS) that promote apoptotic cell death. We showed that cytosolic $NADP^+$-dependent isocitrate dehydrogenase (IDPc) plays an essential role in the control of cellular redox balance and defense against oxidative damage, by supplying NADPH for antioxidant systems. In this study, we demonstrated that knockdown of IDPc expression by RNA interference enhances UVB-induced apoptosis of immortalized human HaCaT keratinocytes. This effect manifested as DNA fragmentation, changes in cellular redox status, mitochondrial dysfunction, and modulation of apoptotic marker expression. Based on our findings, we suggest that attenuation of IDPc expression may protect skin from UVB-mediated damage, by inducing the apoptosis of UV-damaged cells.

• Journal of Life Science
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• v.22 no.1
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• pp.55-61
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• 2012

Akt is known to play an important role in cell proliferation and differentiation, and is also over-expressed in several types of cancer cells. In this study, we explored the anti-proliferative effects of selenium in HT-29 colon cancer cells, mediated through effects on Akt and COX-2. Selenium treatments at different concentrations and for different durations inhibited proliferation of HT-29 colon cancer cells and increased apoptotic cell death. Selenium treatment decreased Akt phosphorylation and COX-2 expression. Treatment with LY294002 (an Akt inhibitor) decreased proliferation of HT-29 cells, while a combined treatment with LY294002 and selenium resulted in even further decreases in cell proliferation. Inactivation of Akt by Akt siRNA treatment abolished these inhibitory effects on cell growth. COX-2 expression decreased in Akt transfected cells compared to non-transfected cells. These results suggest that selenium induced both anti-proliferative and apoptotic effects by inhibiting Akt phosphorylation and COX-2 expression. Selenium treatment also appeared to induce synergistic anti-proliferative effects by inhibition of Akt in HT-29 colon cancer cells.

• Journal of Life Science
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• v.30 no.11
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• pp.973-982
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• 2020

In this study, we examined inhibition of adipocyte differentiation associated with the administration of camphor, a substance identified in extracts of the flowering plant Chrysanthemum indicum L. (CI). No camphor-mediated cytotoxicity was observed over a period of 1-10 days in studies targeting cells of the 3T3-L1 adipocyte-like line. Experiments that featured siRNA-mediated suppression of the transmembrane proteins Patched (PTCH) and Smoothened (SMO) resulted in inhibition and activation of differentiation, respectively. Interestingly, inhibition of PTCH typically activates SMO protein targeting and serves to activate hedgehog (HH)-mediated signaling. The results of our study suggest that activation of HH-mediated signaling can inhibit adipocyte differentiation. Furthermore, expression of glioma-associated oncogene homologue 1 (Gli1) was detected by flow cytometry in 62.7±1.5% of cells in response to administration of Lactobacillus rhamnosus (KCTC 3237) and in 60.4±2.2% of cells in response to camphor; these levels are higher than those detected in undifferentiated controls (24.9±3.1%). No change in the state of fermented camphor was identified by gas chromatography-mass spectrometry (GC-MS), but a 15.41% quantitative increase was confirmed in KCTC 3237. Overall, we conclude that administration of camphor resulted in overexpression of SMO and modulated the differential expression of Gli1. Animal studies focused on the impact of camphor as an agent to counteract obesity might be considered in the future. Indeed, camphor and similar physiologically active compounds from fermented CI might be developed as new and effective treatments for obesity.

• Journal of Life Science
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• v.22 no.10
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• pp.1277-1285
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• 2012

The tumor necrosis, factor-related, apoptosis-inducing ligand (TRAIL) is regarded as a potentially useful anticancer agent with excellent selectivity for cancer cells. However, a considerable number of cancer cells are resistant to apoptosis induction by TRAIL. Developing strategies to overcome this resistance are important for the successful use of TRAIL for cancer therapy. Here, we revealed that siRNA-mediated downregulation of SIRT1 or SIRT1 inhibitor Amurensin G upregulated DR5 and c-Myc and downregulated c-$FLIP_{L/S}$ and Mcl-1, which was associated with sensitization of TRAIL-resistant MCF-7 cells to TRAIL. This result was followed by the activation of caspases, PARP cleavage, and downregulation of Bcl-2 in both TRAIL-treated MCF-7 cells transfected with SIRT1 siRNA and cells co-treated with Amurensin G and TRAIL. Our results suggest that the induction of DR5 and downregulation of c-FLIP via suppression of SIRT1 expression may be a useful strategy to increase the susceptibility of TRAIL-resistant cancer cells to TRAIL-induced cell death.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3096-3102
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• 2011

Vanilloid receptor, TRPV1 (transient receptor potential vanilloid 1) is a non-selective cation channel that responds to a variety of pain-eliciting material including capsaicin, pH, heat. Although, membrane trafficking of TRPV1 was not much known so far, TRPV1 was reported to interact with FIP3 (family of Rab11 interacting protein 3). FIP3 was identified as one of Rab11 interacting proteins that is recently reported important in membrane trafficking of several channel proteins directly or indirectly. Therefore, in this study, we examined the role of Rab11 in the membrane trafficking of TRPV1 using cell biological and biochemical techniques. Rab11 was found really colocalized with TRPV1 based on the result of confocal microscopy. However, GST-pulldown assay, one of biochemical technique, found that Rab11 did not interact with TRPV1. Although Rab11 does not interact with TRPV1 directly, we hypothesized that Rab11 is indeed involved in the membrane trafficking of TRPV1. In order to examine further the role of Rab11 in the membrane trafficking of TRPV1, the expression of TRPV1 on the membrane was examined when the expression of Rab11 was decreased down to about 50% by siRNA technique and found decreased significantly. From this result, we can conclude that Rab11 is involved in the membrane trafficking of TRPV1 in a way of including FIP3.

• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.437-444
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• 2006

This study was aimed to elucidate the biological function of OD314 (Apin protein), which is related to ameloblast differentiation and amelogenesis. Apin protein, calcifying epithelial odontogenic (pindborg) tumors (CEOTs)-associated amyloid, were isolated from CEOTs, and has similar nucleotide sequences to OD314. We examined expression of the OD314 mRNA using in-situ hybridization during tooth development in mice. Expression of OD314 and several enamel matrix proteins were examined in the cultured ameloblast cell line up to 28 days by reverse transcription-polymerase chain reaction (RT-PCR) amplification. After inactivation and over-expression of the OD314 gene in ameloblast cell lines using U6 vectordriven RNA interference and CMV-OD314 construct, RT-PCR were performed to evaluate the effect of the OD314 during amelogenesis. The results were as follows: 1. In in-situ hybridization, OD314 mRNAs were more strongly expressed in ameloblast than odontoblast. 2. When ameloblast cells were cultured in the diffcrentiation and mineralization medium for 28 days, the tuftelin mRNA expression was maintained from the beginning to day 14, and then gradually decreased to day 28. The expressions of amelogenin and enamelin were gradually decreased according to the ameloblast differentiation. 3. Inactivation of OD314 by U6-OD314 siRNA construct down-regulated the expression of OD314, MMP-20, and tuftelin, whereas over-expression of OD314 by CMV-OD314 construct up-regulated the expression of OD314 and MMP-20 without change in tuftelin. These results suggest that OD314 is considered as an ameloblast-enriched gene and may play the important roles in ameloblast differentiation and mineralization.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1589-1595
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• 2014

Objective: Forkhead box C2 (FOXC2) is a member of the winged helix/forkhead box (Fox) family of transcription factors. It has been suggested to regulate tumor vasculature, growth, invasion and metastasis, although it has not been studied in cervical cancer. Here, we analyzed FOXC2 expression in cervical tissues corresponding to different stages of cervical cancer development and examined its correlation with clinicopathological characteristics. In addition, we examined the effects of targeting FOXC2 on the biological behavior of human cervical cancer cells. Methods: The expression of FOXC2 in normal human cervix, CIN I-III and cervical cancer was examined by immunohistochemistry and compared among the three groups and between cervical cancers with different pathological subtypes. Endogenous expression of FOXC2 was transiently knocked down in human Hela and SiHa cervical cells by siRNA, and cell viability and migration were examined by scratch and CCK8 assays, respectively. Results: In normal cervical tissue the frequency of positive staining was 25% (10/40 cases), with a staining intensity (PI) of $0.297{\pm}0.520$, in CIN was 65% (26/40cases), with a PI of $3.00{\pm}3.29$, and in cancer was 91.8% (68/74 cases), with a PI of $5.568 {\pm}3.449$. The frequency was 100% in adenocarcinoma (5/5 cases) and 91.3% in SCCs (63/69 cases). The FOXC2 positive expression rate was 88.5% in patients with cervical SCC stage I and 100% in stage II, showing significant differences compared with normal cervix and CIN. With age, pathologic differentiation degree and tumor size, FOXC2 expression showed no significant variation. On transient transfection of Hela and SiHa cells, FOXC2-siRNA inhibition rates were 76.2% and 75.7%; CCK8 results showed reduced proliferation and relative migration (in Hela cells from $64.5{\pm}3.16$ to $49.5{\pm}9.24$ and in SiHa cells from $60.1{\pm}3.05$ to $44.3{\pm}3.98$) (P < 0.05). Conclusion: FOXC2 gene expression increases with malignancy, especially with blood vessel hyperplasia and invasion degree. Targeted silencing was associated with reduced cell proliferation as well as invasion potential.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.781-787
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• 2017

Objective: The early growth response (Egr) family consists of four members (Egr1, Egr2, Egr3, and Egr4) that are zinc finger transcription factors. Among them, Egr3 is involved in transcriptional regulation of target genes during muscle spindle formation and neurite outgrowth. We previously showed that the immunoreactive Egr3 is localized on oocyte spindle and accumulate near the microtubule organizing center during meiosis I in mice. Egr3 was also shown to be localized on spermatocytes. We herein investigated if Egr3 is expressed in mouse gonads and if Egr3 blockade results in any defect in oocyte maturation. Methods: Expression of Egr3 in mouse gonads was examined by reverse transcription-polymerase chain reaction. Full-length Egr3 and truncated Egr3 (${\Delta}Egr3$) complementary RNAs (cRNAs) with Xpress tag at N-terminus and DsRed2 at C-terminus, and small interfering RNA (siRNA) targeting Egr3 were microinjected into mouse oocytes at germinal vesicle stage. Localization of microinjected Egr3 was examined by confocal live imaging and immunofluorescence staining. Results: Egr3 mRNA was detected in mouse ovaries and testes from 1 to 4 week-old mice. An uncharacterized longer transcript containing 5'untranslated region was also detected in 3 and 4 week-old gonads. Microinjected Xpress-Egr3-DsRed2 or Xpress-${\Delta}Egr3$-DsRed2 localized to nuclei and chromosomes during meiotic progression. Microinjection of these cRNAs or Egr3 siRNA in oocytes did not affect meiotic maturation. Immunofluorescence staining of Egr3 in Xpress-${\Delta}Egr3$-DsRed2-injected oocytes showed a positive signal only on meiotic spindle, suggesting that this antibody does not detect endogenous or exogenous Egr3 in mouse oocytes. Conclusion: The results show that Egr3 localizes to chromosomes during meiotic progression and that certain antibodies may not faithfully represent localization of target proteins in oocytes. Egr3 seems to be dispensable during oocyte maturation in mice.