• Biomolecules & Therapeutics
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• v.30 no.4
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• pp.368-379
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• 2022

Hyaluronic acid (HA), a ligand of CD44, accumulates in some types of tumors and is responsible for tumor progression. The nuclear factor erythroid 2-like 2 (NRF2) regulates cytoprotective genes and drug transporters, which promotes therapy resistance in tumors. Previously, we showed that high levels of CD44 are associated with NRF2 activation in cancer stem like-cells. Herein, we demonstrate that HA production was increased in doxorubicin-resistant breast cancer MCF7 cells (MCF7-DR) via the upregulation of HA synthase-2 (HAS2). HA incubation increased NRF2, aldo-keto reductase 1C1 (AKR1C1), and multidrug resistance gene 1 (MDR1) levels. Silencing of HAS2 or CD44 suppressed NRF2 signaling in MCF7-DR, which was accompanied by increased doxorubicin sensitivity. The treatment with a HAS2 inhibitor, 4-methylumbelliferone (4-MU), decreased NRF2, AKR1C1, and MDR1 levels in MCF7-DR. Subsequently, 4-MU treatment inhibited sphere formation and doxorubicin resistance in MCF7-DR. The Cancer Genome Atlas (TCGA) data analysis across 32 types of tumors indicates the amplification of HAS2 gene is a common genetic alteration and is negatively correlated with the overall survival rate. In addition, high HAS2 mRNA levels are associated with increased NRF2 signaling and poor clinical outcome in breast cancer patients. Collectively, these indicate that HAS2 elevation contributes to chemoresistance and sphere formation capacity of drug-resistant MCF7 cells by activating CD44/NRF2 signaling, suggesting a potential benefit of HAS2 inhibition.

• Journal of Korean Dental Hygiene Science
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• v.4 no.2
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• pp.77-88
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• 2021

Background: In this study, the Capstone Design was applied to the clinical dental hygiene course of the Department of Dental Hygiene, and its effect was confirmed by qualitatively evaluating the students' reflection on the capstone design class experience. Methods: This study was conducted for the "Clinical Dental Hygiene and Practice III" course, in which third year students develop the ability to judge and plan dental hygiene based on problem-solving ability and critical thinking. By applying the Capstone Design within the core curriculum of the class, the students analyzed problems based on their major knowledge of dental hygiene in order to improve their ability to manipulate periodontal instruments, and focusedon the process of developing the contents of periodontal instruments by using them. Results: The application of Capstone Design on clinical dental hygiene and practice III classes increased students' active class participation, and through the problem-solving process, students' learning and confidence improved. Conclusion: The Capstone Design can be viewed as a teaching method that promotes the participation of students in the dental hygiene department and can effectively help their learning and confidence through a problem-solving process.

• Journal of Microbiology and Biotechnology
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• v.32 no.6
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• pp.816-823
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• 2022

The rapid spread of superbugs leads to the escalation of infectious diseases, which threatens public health. Endolysins derived from bacteriophages are spotlighted as promising alternative antibiotics against multi-drug resistant bacteria. In this study, we isolated and characterized the novel Salmonella typhimurium phage PBST08. Bioinformatics analysis of the PBST08 genome revealed putative endolysin ST01 with a lysozyme-like domain. Since the lytic activity of the purified ST01 was minor, probably owing to the outer membrane, which blocks accessibility to peptidoglycan, antimicrobial peptide cecropin A (CecA) was fused to the N-terminus of ST01 to disrupt the outer membrane. The resulting CecA::ST01 has been shown to have increased bactericidal activity against gram-negative pathogens including Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, and Enterobacter cloacae and the most affected target was A. baumannii. In the presence of 0.25 µM CecA::ST01, A. baumannii ATCC 17978 strain was completely killed and CCARM 12026 strain was wiped out by 0.5 µM CecA::ST01, which is a clinical isolate of A. baumannii and resistant to multiple drugs including carbapenem. Moreover, the larvae of Galleria mellonella could be rescued up to 58% or 49% by the administration of CecA::ST01 upon infection by A. baumannii 17978 or CCARM 12026 strain. Finally, the antibacterial activity of CecA::ST01 was verified using 31 strains of five gram-negative pathogens by evaluation of minimal inhibitory concentration. Thus, the results indicate that a fusion of antimicrobial peptide to endolysin can enhance antibacterial activity and the spectrum of endolysin where multi-drug resistant gram-negative pathogens can be efficiently controlled.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.855-861
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• 2022

A white-pigmented, non-motile, gram-negative, and rod-shaped bacterium, designated CYS-02^T, was isolated from soil sampled at Suwon, Gyeonggi-do, Republic of Korea. Cells were strictly aerobic, grew optimally at 20-28℃ and hydrolyzed Tween 40. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain CYS-02^T formed a lineage within the family Comamonadaceae and clustered as members of the genus Variovorax. The closest members were Variovorax guangxiensis DSM 27352^T (98.6% sequence similarity), Variovorax paradoxus NBRC 15149^T (98.5%), and Variovorax gossypii JM-310^T (98.3%). The principal respiratory quinone was Q-8 and the major polar lipids contain phosphatidylethanolamine (PE), phosphatidylethanolamine (PG), and diphosphatidylglycerol (DPG). The predominant cellular fatty acids were C_16:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c) and summed feature 8 (C_18:1ω7c and/or C_18:1ω6c). The DNA GC content was 67.7 mol%. The ANI and dDDH values between strain CYS-02T and the closest members in the genus Variovorax were ≤ 79.0 and 22.4%, respectively, and the AAI and POCP values between CYS-02^T and the other related species in the family Comamonadaceae were > 70% and > 50%, respectively. The genome of strain CYS-02^T showed a putative terpene biosynthetic cluster responsible for antioxidant activity which was supported by DPPH radical scavenging activity test. Based on genomic, phenotypic and chemotaxonomic analyses, strain CYS-02^T was classified into a novel species in the genus Variovorax, for which the name Variovorax terrae sp. nov., has been proposed. The type strain is CYS-02^T (= KACC 22656^T = NBRC 00115645^T).

• Genomics & Informatics
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• v.19 no.4
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• pp.38.1-38.7
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• 2021

Kawasaki disease (KD) is an acute pediatric vasculitis that affects genetically susceptible infants and children. To identify coding variants that influence susceptibility to KD, we conducted whole exome sequencing of 159 patients with KD and 902 controls, and performed a replication study in an independent 586 cases and 732 controls. We identified five rare coding variants in five genes (FCRLA, PTGER4, IL17F, CARD11, and SIGLEC10) associated with KD (odds ratio [OR], 1.18 to 4.41; p = 0.0027-0.031). We also performed association analysis in 26 KD patients with coronary artery aneurysms (CAAs; diameter > 5 mm) and 124 patients without CAAs (diameter < 3 mm), and identified another five rare coding variants in five genes (FGFR4, IL31RA, FNDC1, MMP8, and FOXN1), which may be associated with CAA (OR, 3.89 to 37.3; p = 0.0058- 0.0261). These results provide insights into new candidate genes and genetic variants potentially involved in the development of KD and CAA.

• Genomics & Informatics
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• v.19 no.4
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• pp.47.1-47.12
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• 2021

Kaposi's sarcoma-associated herpesvirus (KSHV) is one of the few human oncogenic viruses, which causes a variety of malignancies, including Kaposi's sarcoma, multicentric Castleman disease, and primary effusion lymphoma, particularly in human immunodeficiency virus patients. The currently available treatment options cannot always prevent the invasion and dissemination of this virus. In recent times, siRNA-based therapeutics are gaining prominence over conventional medications as siRNA can be designed to target almost any gene of interest. The ORF57 is a crucial regulatory protein for lytic gene expression of KSHV. Disruption of this gene translation will inevitably inhibit the replication of the virus in the host cell. Therefore, the ORF57 of KSHV could be a potential target for designing siRNA-based therapeutics. Considering both sequence preferences and target site accessibility, several online tools (i-SCORE Designer, Sfold web server) had been utilized to predict the siRNA guide strand against the ORF57. Subsequently, off-target filtration (BLAST), conservancy test (fuzznuc), and thermodynamics analysis (RNAcofold, RNAalifold, and RNA Structure web server) were also performed to select the most suitable siRNA sequences. Finally, two siRNAs were identified that passed all of the filtration phases and fulfilled the thermodynamic criteria. We hope that the siRNAs predicted in this study would be helpful for the development of new effective therapeutics against KSHV.

• Genomics & Informatics
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• v.20 no.1
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• pp.12.1-12.7
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• 2022

The two complete mitochondrial genomes (mitogenomes) of Paedocypris progenetica, the smallest fish in the world which belonged to the Cyprinidae family, were sequenced and assembled. The circular DNA molecules of mitogenomes P1-P. progenetica and S3-P. progenetica were 16,827 and 16,616 bp in length, respectively, and encoded 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one control region. The gene arrangements of P. progenetica were identical to those of other Paedocypris species. BLAST and phylogenetic analyses revealed variations in the mitogenome sequences of two Paedocypris species from Perak and Selangor. The circular DNA molecule of P. progenetica yield a standard vertebrate gene arrangement and an overall nucleotide composition of A 33.0%, T 27.2%, C 23.5%, and G 15.5%. The overall AT content of this species was consistent with that of other species in other genera. The negative GC-skew and positive AT-skew of the control region in P. progenetica indicated rich genetic variability and AT nucleotide bias, respectively. The results of this study provide genomic variation information and enhance the understanding of the mitogenome of P. progenetica. They could later deliver highly valuable new insight into data for phylogenetic analysis and population genetics.

• Genomics & Informatics
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• v.20 no.3
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• pp.31.1-31.15
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• 2022

A pandemic of respiratory disease named coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is reported prostate cancer patients are susceptible to COVID-19 infection. To understand the possible causes of prostate cancer patients' increased vulnerability and mortality from COVID-19 infection, we focused on the two most important agents, transmembrane protease serine subtype 2 (TMPRSS2) and the C-X-C motif 10 (CXCL10). When SARS-CoV-2 binds to the host cell via S protein-angiotensin-converting enzyme-2 receptor interaction, TMPRSS2 contributes in the proteolytic cleavage of the S protein, allowing the viral and cellular membranes to fuse. CXCL10 is a cytokine found in elevated level in both COVID-19 and cancer-causing cytokine storm. We discovered that TMPRSS2 and CXCL10 are overexpressed in prostate cancer and COVID-19 using the UALCAN and GEPIA2 datasets. The functional importance of TMPRSS2 and CXCL10 in prostate cancer development was then determined by analyzing the frequency of genetic changes in their amino acid sequences using the cBioPortal online portal. Finally, we used the PANTHER database to examine the pathology of the targeted genes. We observed that TMPRSS2 and CXCL10, together with their often co-expressed genes, are important in the binding activity and immune responses in prostate cancer and COVID-19 infection, respectively. Finally, we found that TMPRSS2 and CXCL10 are two putative biomarkers responsible for the increased vulnerability and fatality of prostate cancer patients to COVID-19.

• Genomics & Informatics
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• v.20 no.2
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• pp.23.1-23.9
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• 2022

A survival prediction model has recently been developed to evaluate the prognosis of resected nonmetastatic pancreatic ductal adenocarcinoma based on a Cox model using two nationwide databases: Surveillance, Epidemiology and End Results (SEER) and Korea Tumor Registry System-Biliary Pancreas (KOTUS-BP). In this study, we applied two machine learning methods-random survival forests (RSF) and support vector machines (SVM)-for survival analysis and compared their prediction performance using the SEER and KOTUS-BP datasets. Three schemes were used for model development and evaluation. First, we utilized data from SEER for model development and used data from KOTUS-BP for external evaluation. Second, these two datasets were swapped by taking data from KOTUS-BP for model development and data from SEER for external evaluation. Finally, we mixed these two datasets half and half and utilized the mixed datasets for model development and validation. We used 9,624 patients from SEER and 3,281 patients from KOTUS-BP to construct a prediction model with seven covariates: age, sex, histologic differentiation, adjuvant treatment, resection margin status, and the American Joint Committee on Cancer 8th edition T-stage and N-stage. Comparing the three schemes, the performance of the Cox model, RSF, and SVM was better when using the mixed datasets than when using the unmixed datasets. When using the mixed datasets, the C-index, 1-year, 2-year, and 3-year time-dependent areas under the curve for the Cox model were 0.644, 0.698, 0.680, and 0.687, respectively. The Cox model performed slightly better than RSF and SVM.

• Genomics & Informatics
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• v.20 no.3
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• pp.30.1-30.9
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• 2022

Hereditary spastic paraplegia is a not common inherited neurological disorder with heterogeneous clinical expressions. ALDH18A1 (located on 10q24.1) gene-related spastic paraplegias (SPG9A and SPG9B) are rare metabolic disorders caused by dominant and recessive mutations that have been found recently. Autosomal recessive hereditary spastic paraplegia is a common and clinical type of familial spastic paraplegia linked to the SPG11 locus (locates on 15q21.1). There are different symptoms of spastic paraplegia, such as muscle atrophy, moderate mental retardation, short stature, balance problem, and lower limb weakness. Our first proband involves a 45 years old man and our second proband involves a 20 years old woman both are affected by spastic paraplegia disease. Genomic DNA was extracted from the peripheral blood of the patients, their parents, and their siblings using a filter-based methodology and quantified and used for molecular analysis and sequencing. Sequencing libraries were generated using Agilent SureSelect Human All ExonV7 kit, and the qualified libraries are fed into NovaSeq 6000 Illumina sequencers. Sanger sequencing was performed by an ABI prism 3730 sequencer. Here, for the first time, we report two cases, the first one which contains likely pathogenic NM_002860: c.475C>T: p.R159X mutation of the ALDH18A1 and the second one has likely pathogenic NM_001160227.2: c.5454dupA: p.Glu1819Argfs Ter11 mutation of the SPG11 gene and also was identified by the whole-exome sequencing and confirmed by Sanger sequencing. Our aim with this study was to confirm that these two novel variants are direct causes of spastic paraplegia.