• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7675-7679
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• 2013

Background: A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocellular carcinoma (HCC) patients with or without positive HBsAg. Materials and Methods: Paraffin embedded liver tissues were obtained from 124 HCC patients who underwent liver resection and liver biopsy in King Chulalongkorn Memorial Hospital. Restriction fragment length polymorphism (RFLP) was utilized to detect the R249S mutation. Positive results were confirmed by direct sequencing. Results: Sixty four (52%) patients were positive for HBsAg and 18 (15%) were anti-HCV positive. 12 specimens tested positive by RFLP. Ten HCC patients (8.1%) were confirmed to be R249S positive by Sanger sequencing (AGG to AGT). Out of these 10, six were HBsAg positive, and out of the remaining 4, two were anti-HCV positive. The R249S prevalence among HCC patients with positive HBsAg was 9.4% compared to 6.7% for HBsAg negative samples. Patients with the R249S mutation were younger ($55{\pm}10$ vs $60{\pm}13$ year-old) and tended to have a more advanced Edmonson-Steiner grade of HCC, although differences did not reach statistical significance. Conclusions: Our study shows moderate prevalence of aflatoxin B1-related p53 mutation (R249S) in HCC with or without HBsAg. HBsAg positive status was not associated with R249S prevalence.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.7
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• pp.1023-1029
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• 2007

Inhibins participate in the regulation of pituitary follicle-stimulating hormone synthesis and secretion, follicular maturation and steroidogenesis in the female. Inhibin ${\beta}_A$ gene (INHBA) was studied as a candidate gene for the prolificacy of sheep. Single nucleotide polymorphisms of the entire coding region and partial 3' untranslated region of INHBA were detected by PCR-SSCP in two high fecundity breeds (Small Tail Han and Hu sheep) and six low fecundity breeds (Dorset, Texel, German Mutton Merino, South African Mutton Merino, Chinese Merino and Corriedale sheep). Only the PCR products amplified by primers 3, 4 and 5 displayed polymorphisms. For primer 3, genotype CC was only detected in Chinese Merino sheep, genotype AA was detected in the other seven sheep breeds. Genotype BB was only detected in Hu sheep. Only Hu sheep displayed polymorphism. Eight or four nucleotide mutations were revealed between BB or CC and AA, respectively, and these mutations did not result in any amino acid change. For primer 4, genotypes EE, EG and GG were detected in Dorset and German Mutton Merino sheep, genotypes EE, EF and FF were detected in Chinese Merino sheep, only genotype EE was detected in the other five sheep breeds. Only Dorset, German Mutton Merino and Chinese Merino sheep displayed polymorphism. Sequencing revealed one nucleotide mutation ($114G{\rightarrow}A$) of exon 2 of INHBA gene between genotype FF and genotype EE, and this mutation did not cause any amino acid change. Another nucleotide change ($143C{\rightarrow}T$) was identified between genotype GG and genotype EE, and this mutation resulted in an amino acid change of $serine{\rightarrow}leucine$. For primer 5, genotypes KK and KL were detected in German Mutton Merino and Corriedale sheep, genotypes KK, LL and KL were detected in the other six sheep breeds. Genotype MM was only detected in Hu sheep. All of these eight sheep breeds displayed polymorphism. Sequencing revealed one nucleotide mutation ($218A{\rightarrow}G$) of exon 2 of the INHBA gene between genotype LL and genotype KK, and nine nucleotide mutations between genotype MM and genotype KK. These mutations did not alter amino acid sequence. The partial sequence (395 bp for exon 1 and 933 bp for exon 2) of the INHBA gene in Small Tail Han sheep (with genotype KK for primer 5) was submitted into GenBank (accession number EF192431). Small Tail Han sheep displayed polymorphisms only in the fragment amplified by primer 5. The Small Tail Han ewes with genotype LL had 0.53 (p<0.05) or 0.63 (p<0.05) more lambs than those with genotype KL or KK, respectively. The Small Tail Han ewes with genotype KL had 0.10 (p>0.05) more lambs than those with genotype KK.

• Korean Journal of Clinical Laboratory Science
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• v.40 no.1
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• pp.41-47
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• 2008

Colorectal carcinoma is occurred frequently to Korean and so ranked the fourth from various cancers. Due to western dietary life, this cancer has been increased continually. Therefore, the study will be needed to find a candidate gene involved in the development and progression of colorectal carcinoma and to diagnose and treatment helpfully. The striking feature from cancer suppressor genes is known for LOH (loss of heterozygosity), which is the method to find allele genetic loss or mutation of cancer cell. The purpose of this study was designed to find a carcinogenic gene from colon cancer using microsatellite marker on 17th and 18th chromosome from 30 subjects. The LOH was investigated in order of D18S59 57% (17/30), TP53CA 50% (15/30), D18S68 47% (14/30), D18S69 43% (13/30). The genetic mutation depends on loci of colorectal carcinoma was shown higher with 2.44 from colon cancer than with 1.25 from right colorectal carcinoma (p<0.032). The genetic mutation with lymph nodes was investigated higher with 2.69 at mutated group than with 1.14 at non-mutated group (p<0.003). At genetic mutated pattern depends on disease stage, there was higher significant difference at III-IV stage 2.50 than that of I-II stage 1.17, respectively (p=0.015). There was no difference at comparison between histological classification and serological CEA increase. The loss on 18q21 found in this study is highly recurrence loci and was observed 43% for Korean with high recurrence. Therefore, LOH is a very useful tool to detect 18q21 loci in clinical application, prior to the treatment of colorectal carcinoma. After the operation of colorectol carcinoma, the efficient application using LOH at operated part tissue which is designed to protect the recurrence as well as its cure will be needed.

• The Journal of the Korean bone and joint tumor society
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• v.20 no.2
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• pp.99-103
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• 2014

Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary disorder characterised by a variety of different tumor types in children and young adults. That contains with a germline mutation in the tumor suppressor gene Tumor Protein p53 (TP53). That is extremely rare. Furthermore, this is sometimes overlooked. Here, we report a case of LFS which was confirmed by mutational analysis of the p53 gene. Also, literature review is intended to improve understanding of this disease entity.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5449-5454
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• 2014

Although genetic characteristics are considered to be a factor influencing the geographic variation in the prevalence of gallbladder cancer (GBC), they have not been well studied in Bolivia, which has a high prevalence rate of GBC. The purpose of this study was to examine the frequency of TP53 and K-ras mutations in Bolivian patients with GBC and to compare them with our previous data obtained in other high-GBC-prevalence countries, namely Japan, Chile, and Hungary. DNA was extracted from cancer sites in paraffin-embedded tissue from 36 patients using a microdissection technique. TP53 mutations at exons 5 to 8 and K-ras mutations at codons 12, 13 and 61 were examined using direct sequencing techniques. The data obtained were compared with those in the other high-GBC-prevalence countries. Of the 36 patients, 18 (50.0%) had a TP53 mutation (one mutation in each of 17 patients and three mutations in one patient), and only one (2.8%) had a K-ras mutation. Of the 20 TP53 mutations, 12 were of the transition type (60.0%). This rate was significantly lower than that in Chile (12/12, P<0.05). In addition, three mutations were of the CpG transition type (15.0%), which is a feature of endogenous mutation. All three were found in the hot spot region of the TP53 gene. In contrast, G:C to T:A transversion was found in Bolivia, suggesting the presence of exogenous carcinogens. Our findings suggest that the development of GBC in Bolivia is associated with both exogenous carcinogens and endogenous mechanisms. The identification of an environmental risk factor for GBC is needed to confirm these findings.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.84-84
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• 1993

Overexpression of the mutant p53, derived from mutation of the p53 gene which is located on the short arm of chromosome 17 and plays a role in suppression of the tumor, was reported in some human malignancy such as breast or colon carcinoma and suggested to be a prognostic factor. The authors investigated expression of p53 protein by immunohistochemical staining using anti-p53 monoclonal antibody in the paraffin embedded blocks of the 23 patients who were diagnosed at Seoul National University Hospital as adenoid cystic carcinoma of the head and neck between 1982 and 1991, and could be followed-up. 7 cases(34%) out of the 23 cases showed p53 expression, and there was no significant association between p53 positivity and local recurrence(p=0.31) or distant metastasis(p=0.16)

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.231-240
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• 2007

It has been reported the higher incidence rate of gastric cancer in our country. Helicobacter pylori (H. pylori), that exhibited a higher infection rate among Korean people, has been known as a cofactor to cause cancer. Therefore, the aim of this study was to identify correlations among overexpressions of COX-2 (Cyclooxygenase-2) gene, p53 mutation and cell proliferation index related to H. pylori. Taking 28 cases of gastric cancer with H. pylori detection, immunohistochemical staining for COX-2, p53 and Ki-67 were performed. In the H. pylori positive group, the well differentiated type and diffuse type of gastric cancer were distributed in larger area and the expression rate of COX-2 was revealed high. The H. pylori negative group showed higher p53 expression than that of the positive group. However, the statistical correlation between H. pylori and histopathological factors was not observed. The significantly higher expression of COX-2 had were observed in both well differentiated type and the intestinal type of gastric cancer. Although there were no statistical significances, this showed a higher inclination of manifest in the early gastric cancer. p53 exhibited a higher tendency of expression in the well differentiated, moderately differentiated and the intestinal type of gastric cancers including the early gastric cancer. Ki-67 was expressed in a significantly higher fashion along with the increase of age. In addition, it was significantly expressed in well differentiated type and intestinal type of gastric cancer. Therefore, these results suggest that H. pylori, COX-2, p53, and Ki-67 influences on the new occurrence of gastric cancer and its development procedures. In the future, the more researches would be required to focus on a larger category relative to gene expressions in gastric cancer.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.4 no.1
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• pp.5-12
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• 2004

Purpose Phenylketonuria is an inborn error of metabolism, which is inherited as an autosomal recessive trait. PKU is resulting from deficiency of phenylalanine hydroxylase. PAH gene spans about 90 kb on chromosome 12q and comprises 13 exons. In order to define the genetic basis of PKU and the frequencies and distribution of PAH mutations in the Korean population, we analyzed PAH gene in independent 80 patients with PKU. Methods All 13 exons including exon-intron boundaries and 2 kb of 5' upstream region of the PAH gene were analyzed by PCR-direct sequencing methods. Results PAH gene analysis revealed 39 different mutations including 10 novel mutations. The novel mutations consisted of 9 missense mutations (P69S, G103S, N207D, T278S, P281A, L293M, G332V, S391I and A447P) and a novel splice site variant (IVS10-3C>G). R243Q, IVS4-1G>A, and E6-96A>G were the most relevant mutations and they accounted in the whole for 38% of the mutant alleles identified in this study. We also observed that. $BH_4$ responsibility was. associated with genotype of R241C, R53H and R408Q. Conc1ustion Our present study with 80 participants extends the previous results to more comprehensive understanding of PAH allele distribution and frequency in Koreans. Although Korean mutation profile of PAH is similar to those of the nearest oriental populations (Japanese, Chinese, and Taiwanese), several different characteristic features are revealed. The characterization of the genotype-phenotype relationship was also performed. Our data would be very useful information for diagnosis, genetic counseling and planning of dietary and therapeutic strategies in Korean PAH patients.

• The Korean Journal of Cytopathology
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• v.7 no.2
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• pp.144-150
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• 1996

Although bladder cancers are very common, little is known about their molecular pathogenesis. It is known that p53 alteration is found in about 60% of muscle-invasive bladder cancer, necessiating aggressive therapy and poor outcome. We examined the nuclear expression of p53 protein, using D07 monoclonal antibody in the urine samples from 31 patients with transitional cell carcinoma of the bladder to investigate the correlation of p53 overexpression with histologic grades and depth of invasion. The positive rate of p53 protein was 27% in superficial bladder tumor, but increased up to 71% in the invasive bladder carcinomas. The overexpression of p53 protein increased according to Mostofi grading system from 18% in grade I, 45% in grade II, and up to 100% in grade III. The p53 expression tended to be higher in the invasive and high grade bladder cancers than in the superficial and low grade ones(p<0.05). These results suggest that immunohistochemical analysis of the urine specimen in the bladder cancer patients could be a useful method of screening for the presence of p53 mutant protein. The mutant p53 protein expression may be an indicator of bladder cancer with more proliferative potential and/or aggressive biologic behavior.