• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.41-47
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• 1999

To investigate the combined effect of gamma ray irradiation and NaCl treatment on Tradescantia somatic cell pink mutations, potted plants of Tradescantia 4430 were evenly sprayed with NaCl solution(170mM) 24 hours before irradiation(NaCl+${\gamma}$) and after irradiation(${\gamma}$+NaCl). Irradiation doses were 0.3, 0.5, 1.0 and 2.0 Gy of gamma-ray. The plants irradiated only with gamma radiation were used as control group(CT). Frequency of pink mutation increased linearly with irradiation close and the peak interval of elevated mutation frequencies appeared during 6∼12 days aver irradiation in all the experimental groups. The slope of dose-response curve in CT was 5.99($r^2$=0.99), while it were 4.55($r^2$=0.98) in NaCl+${\gamma}$ and 4.33($r^2$=0.99) in ${\gamma}$+NaCl. It seemed that pre- and post-treatment of NaCl had a protective effect it against radiation-induced cell damages since it decreased the slope value by more than 24%. It is suggested that protective effect on DNA damages can be invoked in irradiated stamen hair cells by NaCl treatment.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.21-26
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• 1999

To investigate the combined effect of radiation and pesticide on Tradescantia somatic cell mutations, potted plants of Tradescantia 4430 on which parathion had been sprayed evenly 24 hours before irradiation. Radiation doses were 0.3, 0.5, 1.0 and 2.0 Gy of gamma-ray. The plants irradiated only with the gamma-ray radiation were used as control groups (CT). Pink mutation frequency increased linearly proportional to the radiation dose and the peak interval of elevated mutation frequencies appeared during 7 ~ 11 days after irradiation in both CT and Pa +${\gamma}$ groups. The slope of dose -response curve in CT was 5.99 ($r^2$= 0.988), while it was 3.43 (r$x^-2$=0.981) in Pa+${\gamma}$. It seemed that parathion pretreatment had a protective effect against radiation-induced cell damages since it decreased the slope value by 43%. It is suggested that an adaptive response or radiomodification could be induced in irradiated stamen hair cells by parathion pretreatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.337-344
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• 2000

Germ-line mutations at DNA repair loci confer susceptibility to colon cancer in hereditary non-polypopsis colorectal cancer. Somatic loss of DNA mismatch repair gene has been reported in a large variety of other tumor types. Replication errors(RERs) judged by microsatellite instability(MSI) and its associated mutations have been recognized as an important mechanism in various tumor types. To investigate associations between MSI and oral squamous cell carcinoma, the frequency of MSI using 12 microsatellite markers were analyzed for the series of oral tumors. Of 17 tumors, 8 cases(47%) did not show instability at any of the 12 loci; 5(29%) showed instability at $2{\sim}3$ loci; and 4(24%) showed instability above 4 loci. The 4 cases showing widespread MSI did not differ from those without evidence of instability in terms of age at diagnosis, degree of differentiation, metastasis to lymph node, tumor location or the presence of mutations in the p53 tumor suppressor gene. DCC and D17S 796 were the most frequently detected in MSI analysis. There were no correlation between smoking and MSI frequency, instead, smoking was suggested to increase the mutation rate of p53 and development of oral carcinomas.

• Korean Journal of Radiology
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• v.23 no.1
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• pp.112-123
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• 2022

Objective: To investigate the relationship between ¹⁸F-FDG PET/CT semi-quantitative parameters and the International Association for the Study of Lung Cancer, American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) histopathologic classification, including histological subtypes, proliferation activity, and somatic mutations. Materials and Methods: This retrospective study included 419 patients (150 males, 269 females; median age, 59.0 years; age range, 23.0-84.0 years) who had undergone surgical removal of stage IA-IIIA lung adenocarcinoma and had preoperative PET/CT data of lung tumors. The maximum standardized uptake values (SUVmax), background-subtracted volume (BSV), and background-subtracted lesion activity (BSL) derived from PET/CT were measured. The IASLC/ATS/ERS subtypes, Ki67 score, and epidermal growth factor/anaplastic lymphoma kinase (EGFR/ALK) mutation status were evaluated. The PET/CT semi-quantitative parameters were compared between the tumor subtypes using the Mann-Whitney U test or the Kruskal-Wallis test. The optimum cutoff values of the PET/CT semi-quantitative parameters for distinguishing the IASLC/ATS/ERS subtypes were calculated using receiver operating characteristic curve analysis. The correlation between the PET/CT semi-quantitative parameters and pathological parameters was analyzed using Spearman's correlation. Statistical significance was set at p < 0.05. Results: SUVmax, BSV, and BSL values were significantly higher in invasive adenocarcinoma (IA) than in minimally IA (MIA), and the values were higher in MIA than in adenocarcinoma in situ (AIS) (all p < 0.05). Remarkably, an SUVmax of 0.90 and a BSL of 3.62 were shown to be the optimal cutoff values for differentiating MIA from AIS, manifesting as pure ground-glass nodules with 100% sensitivity and specificity. Metabolic-volumetric parameters (BSV and BSL) were better potential independent factors than metabolic parameters (SUVmax) in differentiating growth patterns. SUVmax and BSL, rather than BSV, were strongly or moderately correlated with Ki67 in most subtypes, except for the micropapillary and solid predominant groups. PET/CT parameters were not correlated with EGFR/ALK mutation status. Conclusion: As noninvasive surrogates, preoperative PET/CT semi-quantitative parameters could imply IASLC/ATS/ERS subtypes and Ki67 index and thus may contribute to improved management of precise surgery and postoperative adjuvant therapy.

• Journal of Korean Neurosurgical Society
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• v.63 no.1
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• pp.26-33
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• 2020

Glioblastoma (GBM) is a disease without any definite cure. Numerous approaches have been tested in efforts to conquer this brain disease, but patients invariably experience recurrence or develop resistance to treatment. New surgical tools, carefully chosen samples, and experimental methods are enabling discoveries at single-cell resolution. The present article reviews the cell-of-origin of isocitrate dehydrogenase (IDH)-wildtype GBM, beginning with the historical background for focusing on cellular origin and introducing the cancer genesis patterned on firework. The authors also review mutations associated with the senescence process in cells of the subventricular zone (SVZ), and biological validation of somatic mutations in a mouse SVZ model. Understanding GBM would facilitate research on the origin of other cancers and may catalyze the development of new management approaches or treatments against IDH-wildtype GBM.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1321-1324
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• 2012

Background: DNA polymerase beta ($pol{\beta}$) is a key enzyme in the base excision repair pathway. It is 39kDa protein, with two subunits, one large subunit of 31 kDa having catalytic activity between exon V to exon XIV, and an 8 kDa smaller subunit having single strand DNA binding activity. Exons V to VII have double strand DNA binding activity, whereas exons VIII to XI account for the nucleotidyl transferase activity and exons XII to XIV the dNTP selection activity. Aim: To examine the association between $pol{\beta}$ polymorphisms and the risk of ovarian cancer, the present case control study was performed using 152 cancer samples and non-metastatic normal samples from the same patients. In this study, mutational analysis of $pol{\beta}$ genomic DNA was undertaken using primers from exons IX to XIV - the portion having catalytic activity. Results: We detected alteration in DNA polymerase beta by SSCP. Two specific heterozygous point mutations of $pol{\beta}$ were identified in Exon 9:486, A->C (polymorphism 1; 11.18%) and in Exon 11:676, A->C (polymorphism 2; 9.86%). The correlation study involving polymorphism 1 and 4 types of tissue showed a significant correlation between mucinous type with a Pearson correlation value of 4.03 (p=0.04). The association among polymorphism 2 with serous type and stage IV together have shown Pearson ${\chi}^2$ value of 3.28 with likelihood ratio of 4.4 (p=0.07) with OR =2.08 (0.3-14.55). This indicates that there is a tendency of correlation among polymorphism 2, serous type and stage IV, indicating a risk factor for ovarian cancer. Conclusion: Hence, the results indicate that there is a tendency for $pol{\beta}$ polymorphisms being a risk factor for ovarian carcinogenesis in India.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.3
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• pp.69-75
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• 2002

Werner's syndrome is a rare autosomal recessive disorder manifesting as premature aging. It is also known to be characterized by a high frequency of malignant tumors, especially sarcomas. However, Werner's syndrome may be not only a premature aging disease but also a cancer syndrome, because the malignant tumors in these patients are different from those of normal population with respect to involved site, histological type, and age of onset. Recent studies found Werner's syndrome was caused by a mutation of Werner helicase suggesting that WRN helicase may participate in metabolism and repair of DNA. And a dysfunction of WRN helicase may induce the genomic instability causing somatic mutations. Further studies of Werner's syndrome associated with sarcoma might give much informations about the normal aging process and the pathogenesis of sarcomas.

• Journal of Medicine and Life Science
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• v.15 no.2
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• pp.46-50
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• 2018

Cancer, a leading mortality disease following cardiovascular disease worldwide, has high incidence as one out of every four adults in Korea. It was known to be caused by several reasons including somatic mutation, activation of oncogene and chromosome aneuploidy. Cancer cells show a faster growth rate and have metastatic and heterogeneous cell populations compared to normal cells. Cancer stem cells, the most invested field in cancer biology, is a theory to explain heterogeneous cell populations of cancer cells among several characteristics of cancer cells, which is providing the theoretical background for incidence of cancer and treatment failure by drug resistance. Cancer stem cells initially explain heterogeneous cell populations of cancer cells based on the same markers of normal stem cells in cancer, in which only cancer stem cells showed heterogeneity of cancer cells and tumor initiating ability of leukemia. Based on these results, cancer stem cells were reported in various solid cancers such as breast cancer, liver cancer, and lung cancer. Breast cancer stem cells were first reported in solid cancer which had tumor initiating ability and further identified as anti-cancer drug resistance. There were several identification methods in breast cancer stem cells such as specific surface markers and culture methods. The discovery of cancer stem cells not only explains heterogeneity of cancer cells, but it also provides theoretical background for targeting cancer stem cells to complete elimination of cancer cells. Many institutes have been developing new anticancer drugs targeting cancer stem cells, but there have not been noticeable results yet. Many researchers also reported a necessity for improvement of current concepts and methods of research on cancer stem cells. Herein, we discuss the limitations and the perspectives of breast cancer stem cells based on the current concept and history.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.537-546
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• 2004

Adiponectin is adipocyte complement-related protein which is highly specialized to play important roles in metabolic and honnonal processes. This protein, called GBP-28, AdipoQ, and Acrp30, is encoded by the adipose most abundant gene transcript 1 (APM1) which locates on human chromosome 3q27 and mouse chromosome 16. In order to determine chromosomal localization of the porcine APM1, we carried out PCR analysis using somatic cell hybrid panel as well as porcine whole genome radiation hybrid (RH) panel. The result showed that the porcine APM1 located on chromosome 13q41 or 13q46-49. These locations were further investigated with the two point analysis of RH panel, revealed the most significant linked marker (LOD score 20.29) being SIAT1 (8 cRs away), where the fat-related QTL located. From the SSCP analysis of APM1 using 8 pig breeds, two distinct SSCP types were detected from K~ native and Korean wild pigs. The determined sequences in Korean native and Korean wild pigs showed that two nucleotide positions (T672C and C705G) were substituted. The primary sequence of the porcine APM1 has 79 to 87% identity with those of human, mouse, and bovine APM1. The domain structures of the porcine APM1 such as signal sequence, hypervariable region, collagenous region. and globular domain are also similar to those of mammalian genes.

• Journal of Korean Society of Forest Science
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• v.13 no.1
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• pp.25-39
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• 1971

Recently successful induction of haploid plant by means of anther culture method has become a big topic among geneticists and plant breeders. The haploid plant can be used as a precious material for such basic researches as mutation or genetics. Once the haploid is obtained, production of homozygous plant is not a difficult problem. The method of producing homozygous plant can, also, be applied to the practical breeding works. When applied to the hybridization of self-fertilizing breeding period would be greatly shortened and in cross-fertilizing vegetables production of uniform hybrid seed would be very easily obtained. Last few years many scientists attempted anther cultures using various plant species, but it was successful only in several species. Unlike the other tissue cultures which use somatic organs or tissues as explants, anther culture seems to be very difficult because the plants or calli have to be induced from the haploid microspores or pollen grains. In the present experiment anther culture of fruit trees and ornamental shrubs of four genera and seven species was attemped. Anthers of Various stages ranging from tetrad and late microspore were cultured on the modified Murashige and Skoog's medium supplemented with various concentrations of auxins and kinetin as growth regulators. Handling of materials, sterilization, and other operations of culture were done by routine methods. The results were summarized as follows: 1. Calli were induced in the anthers of Forsythia Koreana Nak., Rhododendron mucronuratum Turcz., R. yedoense Max. var. Poukhanense Nak., and Prunus armeniaca L. var. ansu Max. No signs of callus were observed in Prunus persica Sieb. et Zucc. var. vurgaris Max., Pyrus ussuriensis var. macrostipes (Nak.), and Prunus salcina Lindley. 2. Calli were easily formed in any of the media with differing concentrations of auxins and kinetin. 3. In F. Koreana calli developed from anther surface and connective. Callus emerging out of anther locule was not observed. 4. Somatic calli arose from filament, connective, and inside of anther wall in R. mucronulatum. Many of the microspores accumulated starch grains. 5. The anther lobes located opposite the filament of R. yedoense turned easily to calli. This phenomenon was not observed in R. mucronulatum. Microspore embedded for a period in the medium became starch pollen. No callus was observed arising from microspore. 6. In P. armeniaca calli were not induced from somatic anther tissues. Instead, callus emerged out of anther locule rupturing the anther slit. Starch was not formed in the microspore. 7. In P. persica, Pyrus ussuriensis, and P. salcina, calli were not observed in the anthers examined more than 60 days after culture. Microspores of these species, however, were free of starch grains even after long period of subculture. 8. It was learned that somatic calli of the species examined arose usually from endothelium of anther wall, septum of two neighboring anther locules, parenchyma tissues of connectives, or anther lobes. 9. In the anther locule of P. armeniaca cultured long in medium, swollen microspores, polynucleate microspores, multicellular pollen grains, or callus mass were frequently observed, this indicating that the callus of this species was microspore-origin. 10. It was clarified that in P. armeniaca production of haploid plant by anther culture might be possible.