Eunhye Kim

A genome-wide association study identifies a breast cancer risk variant in ERBB4 at 2q34: results from the Seoul Breast Cancer Study

IntroductionAlthough approximately 25 common genetic susceptibility loci have been identified to be independently associated with breast cancer risk through genome-wide association studies (GWAS), the genetic risk variants reported to date only explain a small fraction of the heritability of breast cancer. Furthermore, GWAS-identified loci were primarily identified in women of European descent.MethodsTo evaluate previously identified loci in Korean women and to identify additional novel breast cancer susceptibility variants, we conducted a three-stage GWAS that included 6,322 cases and 5,897 controls.ResultsIn the validation study using Stage I of the 2,273 cases and 2,052 controls, seven GWAS-identified loci [5q11.2/MAP3K1 (rs889312 and rs16886165), 5p15.2/ROPN1L (rs1092913), 5q12/MRPS30 (rs7716600), 6q25.1/ESR1 (rs2046210 and rs3734802), 8q24.21 (rs1562430), 10q26.13/FGFR2 (rs10736303), and 16q12.1/TOX3 (rs4784227 and rs3803662)] were significantly associated with breast cancer risk in Korean women (Ptrend < 0.05). To identify additional genetic risk variants, we selected the most promising 17 SNPs in Stage I and replicated these SNPs in 2,052 cases and 2,169 controls (Stage II). Four SNPs were further evaluated in 1,997 cases and 1,676 controls (Stage III). SNP rs13393577 at chromosome 2q34, located in the Epidermal Growth Factor Receptor 4 (ERBB4) gene, showed a consistent association with breast cancer risk with combined odds ratios (95% CI) of 1.53 (1.37-1.70) (combined P for trend = 8.8 × 10-14).ConclusionsThis study shows that seven breast cancer susceptibility loci, which were previously identified in European and/or Chinese populations, could be directly replicated in Korean women. Furthermore, this study provides strong evidence implicating rs13393577 at 2q34 as a new risk variant for breast cancer.

Anti-inflammatory effects of Scutellaria baicalensis extract via suppression of immune modulators and MAP kinase signaling molecules

AIM OF THE STUDYnA herbal preparation using Scutellaria baicalensis (S. baicalensis) Georgi (Huang Qin, SB) was formulated to effectively protect cancer patients from inflammatory reactions. Although SB, is one of the most widely used herbs in oriental medicine for anti-inflammation, anti-cancer, anti-viral, anti-bacterial and tonifying the immune response, the underlying mechanism(s) by which these effects are induced remains unclear.nnnRESULTSnHere, we report that SB displays anti-inflammatory effects in a zymosan-induced mouse air-pouch model by reducing the expression of nitric oxide (NO), inducible NOS (iNOS), Cyclooxygenase2 (COX-2), Prostaglandin E2 (PGE2), Nuclear Factor-kappaB (NF-kappaB) and IkappaBalpha as well as inflammatory cytokines, such as IL-1beta, IL-2, IL-6, IL-12 and TNF-alpha. In a similar manner, SB also reduced the production of nitric oxide, PGE2, IL-1beta, IL-2, IL-6, IL-12 and TNF-alpha, by decreasing the expression of iNOS, COX-2, IkappaB kinase alphabeta (IKKalphabeta) phosphorylation, IkappaBalpha and IkappaBalpha phosphorylation in LPS-treated Raw 264.7 cells. Additionally, SB interfered with the nuclear translocation of NF-kappaB p65 and p50, resulting in NF-kappaB-dependent transcriptional repression. We further demonstrate that SB attenuated the activity of c-Raf-1/MEK1/2, Erk1/2, p38 and JNK phosphorylation in LPS-treated Raw 264.7 cells.nnnCONCLUSIONSnTaken together, these results confirm the strong anti-inflammatory properties of SB by inhibition of iNOS, COX-2, PGE2, IL-1beta, IL-2, IL-6, IL-12 and TNF-alpha expression. This was achieved through the down-regulation of IKKalphabeta, IkappaBalpha, NF-kappaB activation via suppression of c-Raf-1/MEK1/2 (Mitogen-activated protein kinase/ERK kinase) and MAP kinase phosphorylation in the zymosan-induced mice air-pouch and Raw 264.7 cells. These results support the use of SB herbs for its potent anti-inflammatory activity.

Chemical inhibitors destabilize HuR binding to the AU-rich element of TNF-

Hu protein R (HuR) binds to the AU-rich element (ARE) in the 3UTR to stabilize TNF-α mRNA. Here, we identified chemical inhibitors of the interaction between HuR and the ARE of TNF-α mRNA using RNA electrophoretic mobility gel shift assay (EMSA) and filter binding assay. Of 179 chemicals screened, we identified three with a half-maximal inhibitory concentration (IC50) below 10 µM. The IC50 of quercetin, b-40, and b-41 were 1.4, 0.38, and 6.21 µM, respectively, for binding of HuR protein to TNF-α mRNA. Quercetin and b-40 did not inhibit binding of tristetraprolin to the ARE of TNF-α mRNA. When LPS-treated RAW264.7 cells were treated with quercetin and b-40, we observed decreased stability of TNF-α mRNA and decreased levels of secreted TNF-α. From these results, we could find inhibitors for the TNF-α mRNA stability, which might be used advantageously for both the study for post-transcriptional regulation and the discovery of new anti-inflammation drugs.

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A novel electrical DNA biosensor is presented, which consists of gold (Au) nanoscale islands and a single-walled carbon nanotube (SWCNT) network on top of a concentric Au electrode array (also referred to as the CGi). The decorated Au islands on the SWCNT network provide ideal docking sites for ss-DNA probe (p-DNA) molecules. They also provide better adhesion between the SWCNT network and the chip substrate. In addition, the concentric electrode gives asymmetric current voltage characteristics in the solution and provides more flexible bias options to the electrodes. The sensor system is applied to a DNA sensor after functionalization with a 25 mer p-DNA (5-HSC(6)-C(18)-GCCATTCTCACCGGATTCAGTCGTC-3), hereafter called the [CGi+p-DNA]. The response of the DNA sensor has been measured in both real-time during hybridization with the complementary target ss-DNAs (t-DNA) and the static mode after the hybridization and washing steps. A wide dynamic range from the 100 fM to 1 μM has been achieved from the real-time mode and the static mode. Moreover, it is shown that the sensor system differentiates partially mismatched (single nucleotide polymorphism (SNP), half mismatch, noncomplementary) t-DNA, as well. The [CGi] sensor platform can be easily extended to target specific biological recognition elements such as aptamers or proteins.

mRNA

Exposure and risk assessments were conducted to evaluate safety of speed spayer (SS) and power sprayer (PS) used for treatment of insecticide methomyl in apple orchard on the operator. Dermal patches, gloves, socks, and masks were used to monitor the potential dermal exposure, and personal air monitor with XAD-2 resins was used to evaluate the potential inhalation exposure. Validation of methods for limit of detection, limit of quantitation, recovery, reproducibility, linearity of calibration, trapping efficiency, and breakthrough tests were performed to obtain reasonable results for quantitative exposure study of methomyl. During application of methomyl, PS resulted in more dermal exposure than SS. Important contaminated parts of body were upper arms, thigh, chest, shin, hand, forearm, and head for both SS and PS. Exposure rate was 44–176 mL/h. Although the level of inhalation exposure was very low during application, relatively higher level was observed for PS than for SS. During mixing/loading, more dermal exposure occurred by SS than that of PS probably due to drift of wettable powder (WP) formulation. Exposure was mostly observed on hand, and 99.9% of hand exposure to soluble liquid formulation (215 mg) in PS was from spill of liquid formulation on gloves. However, the body exposure ratio to total mixing/loading amount and inhalation exposure during mixing/loading was very low. Margin of safety in risk assessment was much larger than 1 in all cases, indicating low risk.

Multi-order dynamic range DNA sensor using a gold decorated SWCNT random network

A precise single residue analytical method was developed for fungicide cyazofamid in various crops. Apple, mandarin, Korean cabbage, green pepper, potato, and soybean were selected as representative crops, and clean-up system, partition solvent and extraction solvent were optimized. Limit of quantitation (LOQ) of cyazofamid was 2 ng (S/N>10) and good reproducibility was observed with small coefficient of variation (<4%). Excellent linearity was achieved between 0.05 and 20 mg/kg of cyazofamid standard solutions, with coefficients of determination of 1.000. Method limit of quantitation (MLOQ) was 0.02 mg/kg. For recoveries tests, crop samples were macerated and fortified with cyazofamid standard solution at three fortification levels (MLOQ, 10 MLOQ, and 100 MLOQ). And then those were extracted with acetone, concentrated and partitioned with dichloromethane. Then the extracts were concentrated again and cleaned-up through Florisil® column with ethyl acetate: n-hexane (30:70, v/v) before concentration and analysis with HPLC. Good recoveries from 75.3 to 98.5% with coefficients of variation of less than 10% were obtained, regardless of sample type, which satisfies the criteria of KFDA. Those results were reconfirmed with LC-MS/MS. The method established in this study could be applied to most of crops as an official and general method for residue analysis of cyazofamid.

Exposure and risk assessment of insecticide methomyl for applicator during treatment on apple orchard

Most X‐linked nonsyndromic hearing loss is caused by various types of mutations of the POU domain class 3 transcription factor 4 gene (POU3F4). We found five unique missense and frameshift truncation and extension mutations in Korean patients. Two missense mutations (p.Thr211Met and p.Gln229Arg) disturbed transcriptional activity. Two frameshift extension mutations (p.Thr354GlnfsX115 and p.X362ArgextX113) were located outside of POU domain and nuclear localization signal (NLS) at the C‐terminus. POU3F4 protein levels were low and could be restored by MG132, a proteasome inhibitor, in vitro. These mutant POU3F4 proteins were exclusively localized to the cytoplasm and did not have transcriptional activity. Frameshift mutation (p.Leu317PhefsX12) in POU3F4 leads to the truncation of the C‐terminal 44 amino acids spanning the POU domain and NLS. This frameshift truncation mutant protein was located in both the nucleus and cytoplasm and was present at low protein levels. This mutant was also transcriptionally inactive, even in the presence of MG132. From these results, we conclude that frameshift truncation and extension mutations in the C‐terminus of POU3F4 lead to cytoplasmic localization and subsequent proteosomal degradation due to structural aberrations, which cause transcriptional inactivity and thus nonsyndromic hearing loss.

Establishment of analytical method for cyazofamid residue in apple, mandarin, korean cabbage, green pepper, potato and soybean

ETHNOPHARMACOLOGICAL RELEVANCEnGinseng and ginsenosides are frequently used in the treatment of chronic inflammatory diseases. Recently, 20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol (GPD), the main metabolite of ginsenosides, was reported to have both anti-allergic and anti-pruritic effects. The immunomodulatory effects of GPD-fortified ginseng extract (GFGE) on atopic dermatitis (AD)-like symptoms in mice were investigated. This study was designed to investigate the preventive effect of GFGE on AD-like symptoms.nnnMATERIALS AND METHODSnThe effects of orally administered GFGE on Dermatophagoides farinae body extract (DFE)-induced AD-like symptoms in NC/Nga mice were assessed by analyzing dermatitis score, ear thickness, scratching time, skin histological changes, and serum level of macrophage-derived chemokine (MDC). In addition, splenocytes were isolated from the mice and stimulated with anti-CD3 and anti-CD28 monoclonal antibodies to produce cytokines.nnnRESULTSnOral administration of GFGE significantly attenuated DFE-induced increases in dermatitis score, ear thickness, scratching time, and severity of skin lesions in NC/Nga mice. GFGE treatment also reduced level of MDC in serum, infiltration of eosinophils and mast cells in skin, and production of cytokines in splenocytes.nnnCONCLUSIONSnThese results suggest that GFGE might ameliorate DFE-induced AD-like symptoms and be an alternative therapeutic agent for the prevention of AD.

Destabilization and Mislocalization of POU3F4 by C-Terminal Frameshift Truncation and Extension Mutation

A rapid and robust LC–MS/MS method for the analysis of cyazofamid and its metabolite, 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM), in environmental samples (soil and water) and a variety of crops (apple, mandarin, Kimchi cabbage, green pepper, potato and soybean) was established in this study. Those compounds were analyzed by selected reaction monitoring with electrospray ionization (positive mode) on LC–MS/MS. Method limit of quantitations were 2xa0ngxa0g−1 (cyazofamid) and 5xa0ngxa0g−1 (CCIM) for soil/crop samples, while 0.02xa0ngxa0mL−1 (cyazofamid) and 0.05xa0ngxa0mL−1 (CCIM) were achieved for water samples. Matrix effect (%) was different depending on sample matrices. For recovery tests, soil/crop samples were treated with QuEChERS method and water samples were extracted with dichloromethane. The recoveries of target analytes in the environmental and crop samples were 80.2xa0%–105.1xa0% for cyazofamid and 75.1xa0%–99.1xa0% for CCIM (coefficients of variation; ≤16.4xa0%).

20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol-fortified ginseng extract attenuates the development of atopic dermatitis-like symptoms in NC/Nga mice

BackgroundPlasma β-amyloid (Aβ) is a potential candidate for an Alzheimer’s disease (AD) biomarker because blood is an easily accessible bio-fluid, which can be collected routinely, and Aβ is one of the major hallmarks of AD pathogenesis in the brain. However, the association between plasma Aβ levels and AD diagnosis is still unclear due to the instability and inaccurate measurements of plasma Aβ levels in the blood of patients with AD. If a consistent value of plasma Aβ from the blood can be obtained, this might help determine whether plasma Aβ is a potential biomarker for AD diagnosis.MethodsWe predicted the brain amyloid deposit by measuring the plasma Aβ levels. This cross-sectional study included 353 participants (215 cognitively normal, 79 with mild cognitive impairment, and 59 with AD dementia) who underwent Pittsburgh-compound B positron emission tomography (PiB-PET) scans. We treated a mixture of protease inhibitors and phosphatase inhibitors (MPP) and detected plasma Aβ42 and Aβ40 (MPP-Aβ42 and MPP-Aβ40) in a stable manner using xMAP technology.ResultsMPP-Aβ40 and MPP-Aβ42/40 (MPP-Aβs) were significantly different between subjects with positive amyloid deposition (PiB+) and those with negative amyloid deposition (PiB–) (Pu2009<u20090.0001). Furthermore, MPP-Aβ40 (Pu2009<u20090.0001, ru2009=u20090.23) and MPP-Aβ42/40 ratio (Pu2009<u20090.0001, ru2009=u2009–0.23) showed significant correlation with global PiB deposition (standardized uptake value ratio). In addition, our integrated multivariable (MPP-Aβ42/40, gender, age, and apolipoprotein E genotypes) logistic regression model proposes a new standard for the prediction of cerebral amyloid deposition.ConclusionsMPP-Aβ might be one of the potential blood biomarkers for the prediction of PiB-PET positivity in the brain.