• 대한기관식도과학회지
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• 제3권1호
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• pp.70-78
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• 1997

The development of preneoplastic and neoplastic squamous cell proliferations of body sites such as the skin, female lower genital tract, and larynx is strongly associated with specific types of human papillomaviruses (HPV). Antitumor $CD^{8+}$ cells recognize peptide antigens presented on the surface of tumor cells by major histocompatibility complex (MHC) class I molecules. The MHC class I molecule is a heterodimer composed of an integral membrane glycoprotein designated the alpha chain and a noncovalently associated, soluble protein called beta-2-microglobulin( $\beta$ -2-m). Loss of $\beta$-2-m generally eliminates antigen recognition by antitumor $CD^{8+}$ T cells. We evaluated the expression of $\beta$-2-m as a potential means of tumor escape from immune recognition and the presence of HPV DNA as a cause of laryngeal squamous cell carcinomas (SCCs). Laryngeal SCCs (n=39) were analyzed for MHC class I expression by immunohistochemistry and for presence of HPV by in situ hybridization technique. The results were as follows : 1) HPV DNA was detected in 10 (25.64%) out of 39 cases in laryngeal squamous cell carcinomas. 2) MHC class I down-regulation (heterogenous and negative expression) in HPV positive lesions was higher than HPV negative lesions. 3) The expression of MHC class I was related to cellular differentiation regardless of T-stage and nodal involvement. In conclusion, HPV was thought to be the etiological factor of SCC of larynx, and we found that the down-regulation of MHC class I was a common phenomenon In laryngeal SCC and may provide a way for tumor cells to escape from immune surveillance.

• Journal of Microbiology
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• 제44권5호
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• pp.530-536
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• 2006

Bacteriophage P4, a satellite phage of coliphage P2, is a very useful experimental tool for the study of viral capsid assembly and cos-cleavage. For an in vitro cos-cleavage reaction study of the P2-P4 system, new shortened and selectable markers containing P4 derivative plasm ids were designed as a substrate molecules. They were constructed by swapping the non-essential segment of P4 DNA for either the kanamycin resistance (kmr) gene or the ampicillin resistance (apr) gene. The size of the genomes of the resulting markers were 82% (P4 ash8 delRI:: kmr) and 79% (P4 ash8 delRI:: apr) of the wild type P4 genome. To determine the lower limit of genome size that could be packaged into the small P4-size bead, these shortened P4 plasmids were converted to phage particles with infection of the helper phage P2. The conversion of plasmid P4 derivatives to bacteriophage particles was verified by the heat stability test and the burst size determination experiment. CsCl buoyant equilibrium density gradient experiments confirmed not only the genome size of the viable phage form of shortened P4 derivatives, but also their packaging into the small P4-size head. P4 ash8 delRI:: apr turned out to be the smallest P4 genome that can be packaged into P4-sized head.

• International Journal of Oral Biology
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• 제35권4호
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• pp.153-158
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• 2010

Angelica decursiva has been used in Korean traditional medicine as an antitussive, an analgesic, an antipyretic and a cough remedy. However, the anti-cancer properties of Angelica decursiva have not yet been well defined. In our current study the cytotoxic activity of ethanol extracts of Angelica decursiva root (EEAD) and the mechanism of cell death exhibited by EEAD were examined in FaDu human head and neck squamous cell carcinoma cells. The cytotoxic effects of EEAD upon the growth of FaDu cells were examined with an MTT assay. In addition, the mechanism of cell death induced by EEAD was evaluated by DNA fragmentation analysis, immunoblotting and caspase activation measurements. EEAD induced apoptotic cell death in FaDu cells in a concentration- and time-dependent manner, as determined by MTT assay and DNA fragmentation analysis. Furthermore, the proteolytic processing of caspase-3, -7 and -9 was increased by EEAD treatment of FaDu cells. In addition, the activation of caspase-3 and -7 was detected in living FaDu cells by fluorescence microscopy. These results suggest that EEAD can induce apoptosis and suppress cell growth in cancer cells and may have utility as a future anticancer therapy.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권6호
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• pp.468-473
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• 2005

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide. The molecular mechanisms involved in the development and progression of these carcinomas are not well known. Abnormalities of genomic methylation patterns have been attributed a role in carcinogenesis and local de novo methylation at tumor suppressor loci was held to be involved in silencing of tumor suppressor genes. Using Ms APPCR, we previously isolated a hypermethylated fragment corresponded to the 5' end of TPEF gene from primary liver and lung cancer cells. To confirm the inactivation of TPEF gene by hypermethylation in HNSCC, we investigated correlation between methylation pattern and expression of TPEF in 10 HNSCC cell lines. In methylation analysis such as combined-bisulfite restriction analysis(COBRA) and bisulfite sequencing, only RPMI 2650 showed none methylated pattern and another 9 cell lines showed dense methylation. The TPEF gene expression level analysis using RT-PCR showed that these 9 cell lines had not or significantly low expression levels of TPEF as compared with RPMI 2650. In addition, the increase of TPEF reexpression by 5-AzaC as demethylating agent in 9 cell lines also indicated that TPEF expression was regulated by hypermethylation. These results of this study demonstrate that epigenetic silencing of TPEF gene by aberrant methylation could play an important role in HNSCC carcinogenesis.

• Genes and Genomics
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• 제40권12호
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• pp.1279-1285
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• 2018

Interdigitating dendritic cell sarcoma (IDCS) is an aggressive neoplasm and is an extremely rare disease, with a challenging diagnosis. Etiology of IDCS is also unknown and most studies with only case reports. In our case, immunohistochemistry showed that the tumor cells were positive for S100, CD45, and CD68, but negative for CD1a and CD21. This study aimed to investigate the causative factors of IDCS by sequencing the protein-coding regions of IDCS. We performed whole-exome sequencing with genomic DNA from blood and sarcoma tissue of the IDCS patient using the Illumina Hiseq 2500 platform. After that, we conducted Sanger sequencing for validation of sarcoma-specific variants and gene ontology analysis using DAVID bioinformatics resources. Through comparing sequencing data of sarcoma with normal blood, we obtained 15 nonsynonymous single nucleotide polymorphisms (SNPs) as sarcoma-specific variants. Although the 15 SNPs were not validated by Sanger sequencing due to tumor heterogeneity and low sensitivity of Sanger sequencing, we examined the function of the genes in which each SNP is located. Based on previous studies and gene ontology database, we found that POLQ encoding DNA polymerase theta enzyme and FNIP1 encoding tumor suppressor folliculin-interacting protein might have contributed to the IDCS. Our study provides potential causative genetic factors of IDCS and plays a role in advancing the understanding of IDCS pathogenesis.

• Imaging Science in Dentistry
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• 제31권4호
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• pp.227-233
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• 2001

Purpose: The purpose of this study was to investigate the apoptosis induction in tissues constituting the craniofacial region of growing rat by irradiation. Materials and Methods: The submandibular gland, brain, articular cartilage of condylar head, and calvarium were extracted from 20-day-old rats irradiated 10 Gy. Apoptosis of each tissue was examined by DNA fragmentation and estimated quantitatively using apoptotic index on TUNEL assay. Apoptotic index of each tissue was calculated by the equation for apoptotic cells/total cells × 1,000 on the images of confocal laser scanning microscopy. Apoptotic index was analyzed statistically according to the time lapse after irradiation on the tissues. Results : In the submandibular gland, apoptotic index was significantly increased from 6 hours after irradiation showing the highest value at 12 hours and decreased to the control level at 3 days after irradiation. In the brain, apoptotic index was abruptly reached to the maximum value at 6 hours after irradiation and decreased to the control level at 4 days after irradiation. Articular cartilage and calvarium showed no or little apoptotic signals. The results obtained by the apoptotic index accorded with that of DNA fragmentation. Conclusion : Radiation was closely related with the apoptosis of submandibular gland and brain but, not related with the apoptosis of the articular cartilage of condylar head and calvarium. The changes induced by radiation of the hard tissues would not be explained by apoptosis.

• 한국어류학회지
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• 제29권4호
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• pp.244-251
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• 2017

본 연구는 2016년에 한국 남해에서 채집된 둥글넙치과 자어를 분자방법으로 동정하였으며, 자어의 크기별 외부 형태를 상세히 기술하였다. 채집된 자어 15개체 (3.53~19.49 mm 체장)의 mitochondrial DNA (mtDNA) cytochrome c oxidase subunit I gene (COI) 434 bp의 염기서열을 비교한 결과, 모두 사량넙치로 확인되었다. 사량넙치의 자어는 2개의 길게 연장된 등지느러미 기조를 가지며, 등지느러미와 뒷지느러미 기저에 흑색소포가 일렬로 나 있는 반면 체측에는 흑색소포가 없었다. 성장하면서 체장에 대한 두장 및 두고의 비율이 증가 추세에서 감소 추세로 바뀌는 변곡점이 체장 9.93 mm~10.73mm에서 확인되었다. 사량넙치 자어는 형태적으로 가장 유사한 동백가자미(Psettina iijimae)와 달리 등지느러미와 뒷지느러미의 기저 근처에 흑색소포군을 가지지 않는 점에서 잘 구분된다.

• 대한두경부종양학회지
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• 제18권1호
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• pp.3-10
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• 2002

Background: The molecular pathogenesis of hereditary medullary thyroid carcinoma is well known to be associated with germ-line mutation in the RET proto-oncogene and sporadic medullary thyroid carcinoma has been shown to carry somatic RET mutation especially in exon 13 and 16. The aim of this study is to evaluate the genetic background in the pathogenesis of the sporadic medullary thyroid carcinoma which shows extremely high incidence in Korea. Materials and Methods: Direct DNA sequencing for RET exon 13 and 16, as well as immunohistochemistrical assay for a monoclonal RET antibody were performed from 20 cases of archival tissues of medullary thyroid carcinoma. Results: Monoclonal RET antibody with C-terminal epitope showed comparatively stronger expression in tumor cells than in normal tissues and immunoreactive area in the tumor was $66.0{\pm}40.1%$. Direct sequencing of RET exon 13 revealed 4 cases of mis-sense mutations in Codon 778, Codon 767, and both in Codon 768 and 778. One case showed a silent mutation (ACG-ACT) in RET exon 16 (Codon 926). Conclusions: The strong RET immunoreactivity of medullary thyroid carcinoma may suggest that there could be a genetic alteration in oncoprotein level. RET proto-oncogene mutation may be involved in the evolutional process of medullary thyroid carcinoma in the aspect of molecular basis.

• BMB Reports
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• 제33권3호
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• pp.208-212
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• 2000

In order to develop a specific genetic marker for the Korean native cattle (Hanwoo), an arbitrarily-primed polymerase chain reaction (AP-PCR) analysis of 6 different cattle breeds was attempted. Eight different arbitrary primers, each longer than 20-mer nucleotides, were used. In comparison to the AP-PCR patterns, several distinctive DNA bands that are specific for a certain breed were detected. When the primer Kpn-X was employed, a 280bp DNA fragment was found to be specific only for Hanwoo. In an individual analysis of Hanwoo, this AP-PCR marker was observed in 123 head of cattle among the 153 that were tested (80.4%). Nucleotide sequencing revealed that this fragment has a short microsatellite sequence of tandem repeat, $A(G)_{1-2}\;(C)_{1-3}AGAG$. According to the analysis of AP-PCR band patterns, Hanwoo was discovered to be genetically most closely-related with Holstein among the various cattle breeds.

• 한국동물생명공학회지
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• 제36권4호
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• pp.314-322
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• 2021

Paired box protein, PAX7, is a key molecule for the specification, maintenance and skeletal muscle regeneration of muscle satellite cells. In this study, we identified and characterized the cDNA and amino acid sequences of PAX7 from black sea bream (Acanthopagrus schlegelii) via molecular cloning and sequence analysis. A. schlegelii PAX7 cDNA was comprised of 1,524 bp encoding 507 amino acids and multiple sequence alignment analysis of the translated amino acids showed that it contained three domains including paired DNA-binding domain, homeobox domain and OAR domain which were well conserved across various animal species investigated. Pairwise Sequence Alignment indicated that A. schlegelii PAX7 had the same amino acid sequences with that of yellowfin seabream (A. latus) and 99.8% identity and similarity with that of gilt-head bream (Sparus aurata). Molecular phylogenetic analysis confirmed that A. schlegelii PAX7 formed a monophyletic group with those of teleost and most closely related with those of the fish that belong to Sparidae family including A. latus and S. aurata. In the investigation of its tissue specific mRNA expression, the expression was specifically identified in skeletal muscle tissue and a weak expression was also shown in gonad tissue. The cultured cells derived from skeletal muscle tissues expressed PAX7 mRNA at early passage but the expression was not observed after several times of subculture.