• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2747-2751
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• 2014

Background: DNA repair pathways play a crucial role in maintaining the human genome. Previous studies associated DNA repair gene polymorphisms (XPD Lys751Gln, XRCC1 Arg280His and XRCC1 Arg399Gln) with nasopharyngeal carcinoma. These non-synonymous polymorphisms may alter DNA repair capacity and thus increase or decrease susceptibility. The present study aimed to determine the genotype distribution of XPD codon 751, XRCC1 codon 280 and codon 399 polymorphisms and haplotype associations among NPC cases and controls in the Malaysian population. Materials and Methods: We selected 157 NPC cases and 136 controls from two hospitals in Kuala Lumpur, Malaysia for this study. The polymorphisms studied were genotyped by PCR-RFLP assay and allele and genotype frequenci es, haplotype and linkage disequilibrium were determined using SNPstat software. Results: For the XPD Lys751Gln polymorphism, the frequency of the Lys allele was higher in cases than in controls (94.5% versus 85.0%). For the XRCC1 Arg280His polymorphism, the frequency of Arg allele was 90.0% and 89.0% in cases and controls, respectively and for XRCC1 Arg399Gln the frequency of the Arg allele was 72.0% and 72.8% in cases and controls respectively. All three polymorphisms were in linkage disequilibrium. The odds ratio from haplotype analysis for these three polymorphisms and their association with NPC was 1.93 (95%CI: 0.90-4.16) for haplotype CGC vs AGC allele combinations. The global haplotypte association with NPC gave a p-value of 0.054. Conclusions: Our study provides an estimate of allele and genotype frequencies of XRCC1Arg280His, XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms in the Malaysian population and showed no association with nasopharyngeal cancer.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2125-2134
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• 2015

IrrE is a highly conserved global regulator in the Deinococcus genus and contributes to survival from high doses of UV radiation, ionizing radiation, and desiccation. Drad-IrrE and Dgob-IrrE from Deinococcus radiodurans and Deinococcus gobiensis I-0 each share 66% sequence identity. However, Dgob-IrrE showed a stronger protection phenotype against UV radiation than Drad-IrrE in the D. radiodurans irrE-deletion mutant (ΔirrE), which may be due to amino acid residues differences around the DNA-binding HTH domain. Site-directed mutagenesis was used to generate a Drad-IrrE A184S single mutant, which has been characterized and compared with the ΔirrE mutant complemented strain with Drad-irrE, designated ΔirrE-E. The effects of the A184S mutation following UV radiation and mitomycin C (MMC) shock were determined. The A184S mutant displayed significantly increased resistance to UV radiation and MMC shock. The corresponding A184 site in Dgob-IrrE was inversely mutated, generating the S131A mutant, which exhibited a loss of resistance against UV radiation, MMC shock, and desiccation. qPCR analysis revealed that critical genes in the DNA repair system, such as recA, pprA, uvrA, and ddrB, were remarkably induced after UV radiation and MMC shock in the ΔirrE-IE and A184S mutants. These data suggested that A184S improves the ability against UV radiation and MMC shock, providing new insights into the modification of IrrE. We speculated that the serine residue may determine the efficiency of DNA binding, leading to the increased expression of IrrE-dependent genes important for protection against DNA damage.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.173-182
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• 2018

Recent studies have provided several lines of evidence that peripheral administration of oxytocin induces analgesia in human and rodents. However, the exact underlying mechanism of analgesia still remains elusive. In the present study, we aimed to identify which receptor could mediate the analgesic effect of intraperitoneal injection of oxytocin and its cellular mechanisms in thermal pain behavior. We found that oxytocin-induced analgesia could be reversed by $d(CH_2)_5[Tyr(Me)^2,Dab^5]$ AVP, a vasopressin-1a (V1a) receptor antagonist, but not by $desGly-NH_2-d(CH_2)_5[D-Tyr^2,Thr^4]OVT$, an oxytocin receptor antagonist. Single cell RT-PCR analysis revealed that V1a receptor, compared to oxytocin, vasopressin-1b and vasopressin-2 receptors, was more profoundly expressed in dorsal root ganglion (DRG) neurons and the expression of V1a receptor was predominant in transient receptor potential vanilloid 1 (TRPV1)-expressing DRG neurons. Fura-2 based calcium imaging experiments showed that capsaicin-induced calcium transient was significantly inhibited by oxytocin and that such inhibition was reversed by V1a receptor antagonist. Additionally, whole cell patch clamp recording demonstrated that oxytocin significantly increased potassium conductance via V1a receptor in DRG neurons. Taken together, our findings suggest that analgesic effects produced by peripheral administration of oxytocin were attributable to the activation of V1a receptor, resulting in reduction of TRPV1 activity and enhancement of potassium conductance in DRG neurons.

• Journal of Pharmacopuncture
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• v.18 no.4
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• pp.20-25
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• 2015

Objectives: Recently, thread-embedding therapy (TET) has been widely applied in Korean medicine for cosmetic purposes such as reducing skin wrinkles. An inserted thread was reported to have induced continuous stimulation, followed by support for connective tissue regeneration. However, the potential role of TET in hair-growth has not yet been reported. Methods: We designed this study to evaluate whether TET has a hair-growth-promoting effect. C57 black 6 (C57BL/6) mice were divided into three groups: normal saline-treated, minoxidil-treated, and thread-embedded groups. Normal saline or 5% minoxidil was topically sprayed on the dorsal skin of the mice once a day for 16 days. Medical threads were embedded into the dorsal skin of the mice in a single application. Hair growth activity was evaluated by using dermoscopic and microscopic observations. Sections of the dorsal skin were stained with hematoxylin and eosin. Expressions of bromodeoxyuridine (BrdU), proliferating cell nuclear antigen (PCNA), fibroblast growth factor-7 (FGF-7), and fibroblast growth factor-5 (FGF-5) were detected by using immunohistochemical staining. A reverse transcription-polymerase chain reaction (RT-PCR) analysis was adopted to measure the messenger RNA (mRNA) expressions of FGF-7 and FGF-5. Results: TET enhanced anagen development in the hair follicles of C57BL/6 mice. The expressions of BrdU and PCNA, both of which imply active cellular proliferation, were increased by using TET. Moreover, TET increased the expression of FGF-7, an anagen-inducing growth factor, while decreasing the expression of FGF-5, an anagen-cessation growth factor, both at the protein and the mRNA levels. Conclusion: TET enhanced hair re-growth in C57BL/6 mice. TET regulated the expressions of anagen-associated growth factors and activated the proliferation of hair follicular cells in depilated skin lesions. Considering its long-lasting effect, TET may be a good alternative therapeutic for the treatment of alopecia.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1529-1538
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• 2017

Klebsiella pneumoniae is an opportunistic and clinically significant emerging pathogen. We investigated the relative roles of Toll-like receptor (TLR) 2 and TLR4 in initiating host defenses against K. pneumoniae. TLR2 knockout (KO), TLR4 KO, TLR2/4 double KO (DKO), and wild-type (WT) mice were inoculated with K. pneumoniae. Mice in each group were sacrificed after either 12 or 24h, and the lungs, liver, and blood were harvested to enumerate bacterial colony-forming units (CFU). Cytokine and chemokine levels were analyzed using enzyme-linked immunosorbent assay and real-time PCR, and pneumonia severity was determined by histopathological analysis. Survival was significantly shortened in TLR4 KO and TLR2/4 DKO mice compared with that of WT mice after infection with $5{\times}10^3CFU$. TLR2 KO mice were more susceptible to infection than WT mice after exposure to a higher infectious dose. Bacterial burdens in the lungs and liver were significantly higher in TLR2/4 DKO mice than in WT mice. Serum $TNF-{\alpha}$, MCP-1, MIP-2, and nitric oxide levels were significantly decreased in TLR2/4 DKO mice relative to those in WT mice, and TLR2/4 DKO mice showed significantly decreased levels of $TNF-{\alpha}$, IL-6, MCP-1, and inducible nitric oxide synthase mRNA in the lung compared with those in WT mice. Collectively, these data indicate that TLR2/4 DKO mice were more susceptible to K. pneumoniae infection than single TLR2 KO and TLR4 KO mice. These results suggest that TLR2 and TLR4 play cooperative roles in lung innate immune responses and bacterial dissemination, resulting in systemic inflammation during K. pneumoniae infection.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.126-135
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• 2003

Background: One of the important factors in the prognosis of chronic hepatitis B patient is the degree of replication of hepatitis B virus (HBV). It has been known that HBV DNA polymerase plays the essential role in the replication of HBV. HBV DNA polymerase is composed of four domains, TP (Terminal protein), spacer, RT (Reverse transcriptase) and RNaseH. Among these domains, tyrosine, the $65^{th}$ residue of TP is an important residue in protein-priming reaction that initiates reverse transcription. If monoclonal antibody that recognizes around tyrosine residue were selected, it could be applied to further study of HBV replication. Methods: To produce TP-specific scFv (single-chain Fv) by phage display, mice were immunized using synthetic TP-peptide contains $57{\sim}80^{th}$ amino acid residues of TP domain. After isolation of mRNA of heavy-variable region ($V_H$) and light-chain variable region ($V_L$) from the spleen of the immunized mouse, DNA of $V_H$ and $V_L$ were obtained by RT-PCR and joined by a DNA linker encoding peptide (Gly4Ser)3 as a scFv DNA fragments. ScFv DNA fragments were cloned into a phagemid vector. scFv was expressed in E.coli TG1 as a fusion protein with E tag and phage gIII. To select the scFv that has specific affinity to TP-peptide from the phage-antibody library, we used two cycles of panning and colony lift assay. Results: The TP-peptide-specific scFv was isolated by selection process using TP-peptide as an antigen. Selected scFv had 30 kDa of protein size and its nucleotide sequences were analyzed. Indirect- and competitive-ELISA revealed that the selected scFv specifically recognized both TP-peptide and the HBV DNA polymerase. Conclusion: The scFv that recognizes the TP domain of the HBV DNA polymerase was isolated by phage display.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.10-20
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• 2011

Genetic determinant for metallothionein (MT), a cysteine-rich protein playing essential roles in metal detoxification and homeostasis, was characterized in the Korean bitterling (Acheilognathus signifer, Cyprinidae), an endemic fish species. The full-length A. signifer MT (AsMT) cDNA (551 bp) is composed of a single open-reading frame (ORF) to encode a polypeptide of 60 amino acids containing 20 cysteine residues whose positions are conserved in most cypriniform MTs. At the genomic level, the AsMT (2,593 bp spanning the 5'-flanking region to the 3'-untranslated region) represented a conserved tripartite (three exons interrupted by two introns) structure with AT-rich introns. The upstream regulatory region (-1,914 bp from the ATG initiation codon) of AsMT displayed various sites and motifs for transcription factors involved in the metal-mediated regulation and stress/immune responses. The AsMT transcript was ubiquitously detected in various organs with variable expression levels, where the ovary and intestine showed the highest expression, while the heart and skeletal muscle represented the lowest level. During an exposure to copper (immersion in $0.5\;{\mu}M$ Cu for 48 h), the levels of AsMT transcripts were significantly elevated in the liver (more than 3.5-fold), moderately in the gill, kidney, and spleen (ranging from 1.5- to 2.5-fold), and barely in the brain and intestine. Results of this study could form a useful basis to explore the metal-related stress physiology of this endangered fish species.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6155-6157
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• 2012

Background: Mutations in the MAPK (Mitogen Activated Protein Kinase) signaling pathway - EGFR/Ras/RAF/MEK have been associated with the development of several carcinomas. ERK2, a downstream target of the MAPK pathway and a founding member of the MAPK family is activated by cellular signals emanating at the cell membrane. Activated ERK2 translocates into the nucleus to transactivate genes that promote cell proliferation. MKP - a dual specific phosphatase - interacts with activated ERK2 via the common docking (CD) domain of the later to inactivate (dephosphorylate) and effectively terminate further cell proliferation. A constitutively active form of ERK2 carrying a single point mutation - E322K in its CD domain, was earlier reported by our laboratory. In the present study, we investigated the prevalence of this CD domain E322K mutation in 88 well differentiated OSCC tissue samples. Materials and Method: Genomic DNA specimens isolated from 88 oral squamous cell carcinoma tissue samples were amplified with primers flanking the CD domain of the ERK2 gene. Subsequently, PCR amplicons were gel purified and subjected to direct sequencing to screen for mutations. Results: Direct sequencing of eighty eight OSCC samples identified an E322K CD domain mutation in only one (1.1%) OSCC sample. Conclusions: Our result indicates that mutation in the CD domain of ERK2 is rare in OSCC patients, which suggests the role of genetic alterations in other mitogenic genes in the development of carcinoma in the rest of the patients. Nevertheless, the finding is clinically significant, as the relatively rare prevalence of the E322K mutation in OSCC suggests that ERK2, being a common end point signal in the multi-hierarchical mitogen activated signaling pathway may be explored as a viable drug target in the treatment of OSCC.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1603-1609
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• 2014

Background: The response to treatment and overall survival (OS) of patients with acute myeloid leukemia (AML) is variable, with a median ranging from 6 months to 11.5 years. TP53 is associated with old age, chemotherapy resistance, and worse OS. Using genetic sequencing, we set out to look at our own experience with AML, and hypothesized that both TP53 mutations and SNPs at codon 72 would mimic the literature by occurring in a minority of patients, and conferring a worse OS. Materials and Methods: We performed a pilot study of randomly selected, newly diagnosed AML patients at Mount Sinai Medical Center, diagnosed from 2005-2008 (n=10). TP53 PCR sequencing was performed using DNA from bone marrow smears. Analysis was accomplished using Mutation Surveyor software with confirmation of the variants using the COSMIC and dbSNP databases. Results: Fewer than half of the patients harbored TP53 mutations (40%). There was no significant difference in OS based on gender, AML history, risk-stratified karyotype, or TP53 mutation. There were possible trends toward improved survival among patients less than 60 (11 vs 4 months, p=0.09), Hispanics (8 vs 1 months, p=0.11), and those not harboring SNP P72R (8 vs 2 months, p=0.10). There was a significant improvement in survival among patients with better performance status (28 vs 4 months, p=0.01) and those who did not have a complex karyotype (8 vs 1 months, p=0.03). The most commonly observed TP53 mutation was a missense N310K (40%) and the most commonly observed SNP was P72R (100.0%). Conclusions: Our study confirms previous reports that poor PS and the presence of a complex karyotype are associated with a decreased OS. In our cohort, TP53 mutations were relatively common, occurring more frequently in male patients with an adverse karyotype. Although there was no significant difference in survival between TP53 mutated and un-mutated patients, there was a possible trend toward worse OS among patients with SNP P72R. Larger studies are needed to validate these findings.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7965-7970
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• 2014

One of the goals of tumor immunotherapy is to generate immune cells with potent anti-tumor activity through in vitro techniques using peripheral blood collected from patients. However, cancer patients generally have poor immunological function. Thus using patient T cells, which have reduced in vitro proliferative capabilities and less tumor cell killing activity to generate lymphokine-activated killer (LAK) cells, fails to achieve optimal clinical efficacy. Interleukin-2 (IL-2) is a potent activating cytokine for both T cells and natural killer cells. Thus, this study aimed to identify optimal donors for allogeneic LAK cell immunotherapy based on single nucleotide polymorphisms (SNP) in the IL-2 and IL-2R genes. IL-2 and IL-2R SNPs were analyzed using HRM-PCR. LAK cells were derived from peripheral blood mononuclear cells by culturing with IL-2. The frequency and tumor-killing activity of LAK cells in each group were analyzed by flow cytometry and tumor cell killing assays, respectively. Regarding polymorphisms at IL-2-330 (rs2069762) T/G, LAK cells from GG donors had significantly greater proliferation, tumor-killing activity, and IFN-${\gamma}$ production than LAK cells from TT donors (P<0.05). Regarding polymorphisms at IL-2R rs2104286 A/G, LAK cell proliferation and tumor cell killing were significantly greater in LAK cells from AA donors than GG donors (P<0.05). These data suggest that either IL-2-330(rs2069762)T/G GG donors or IL-2R rs2104286 A/G AA donors are excellent candidates for allogeneic LAK cell immunotherapy.