• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1053-1055
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• 2016

Background: Polycythemia rubra vera (PV), being a primary polycythemia, is caused by neoplastic proliferation of erythroid, megakaryocytic and granulocytic lineages which result in panmyelosis. PV patients have a somatic acquired mutation in the Janus kinase (JAK2) pathway, rendering cell proliferation independent of the normal regulatory mechanisms that regulate erythropoiesis. The rational of this study was to determine the prevalence of the JAK-2 V617F mutation in Pakistani patients with PV. Materials and Methods: In this cross sectional study, 26 patients with PV were enrolled from January 2010 to December 2014. Patients were diagnosed based on WHO criteria for PV. All were screened for G-T point mutation (V617F) in the JAK2 gene on chromosome 9 by an allele specific PCR. Results: The mean age was $53.4{\pm}9.31years$ (range 36-72) and the male to female ratio was 2:1. The frequency of JAK2 V617F positivity in our PV patients was found to be 92.3%. Overall 30.7% of patients were asymptomatic and remaining 69.3% presented with symptomatic disease. The mean hemoglobin was $18.1{\pm}1.9g/dl$ with the mean hematocrit of $55.6{\pm}8.3%$. The mean total leukocyte count was $12.8{\pm}7.1{\times}10^9/l$ and the platelet count was $511{\pm}341.9{\times}10^9/l$. A positive correlation of JAK2 V617F mutation was established with high TLC count (P=0.01). No correlation of JAK2 V617F could be established with age or gender (P>0.05). Conclusions: The JAK2 V617F mutation frequency in our PV patients was similar to those reported internationally. Screening for the mutation in all suspected PV cases could be beneficial in differentiating patients with reactive and clonal erythrocytosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권4호
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• pp.337-344
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• 2000

본 연구에서는 MSI와 구강암과의 상관관계를 규명하기 위하여 17례의 구강암에 대하여 12종류의 marker를 이용하여 MSI 빈도를 조사하였으며, 동시에 p53단백의 과발현과 유전자 돌연변이 양상에 대해서도 알아보았다. 그 결과 4종류 이상의 marker에 대해서 MSI가 나타나는 widespread MSI의 경우 임상병리학적으로 뚜렷한 특징이 없었다. 또한 흡연과 MSI 빈도간에도 연관성이 없었으나 흡연은 p53 유전자의 돌연변이를 증가시켜 암화과정을 촉진하는 작용을 하는 것으로 나타났다.

• Tuberculosis and Respiratory Diseases
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• 제45권2호
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• pp.333-340
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• 1998

연구배경: 폐암은 전세계적으로 암중에서도 높은 발생빈도를 보이는 질환이며 흡연, 공해와 환경오염 등으로 인해 점차 증가하고 있다. 폐암에서는 다양한 유전학적 변화가 나타나는데 그중에서도 특히 p53의 유전자 변이와 그에 따른 p53 본래의 종양억제력의 상실은 종양발생에 관련되는 것으로 밝혀져 있다. P53 변이의 확인은 면역조직염색, PCR 분석법과 ESISA 분석 등으로 조사할 수 있다. 방 법: P53의 혈청학적 측정은 69명의 폐암환자와 대조군으로 42명 비폐암 호흡기질환자에서 조사되었다. 혈청 p53 변이단백은 ELISA 방법으로 측정하였고 조직 면역화학염색은 p53의 단크론항체를 이용하였다. 결 과: 혈청학적 검사에서 비소세포 폐암의 p53 변이단백은 0.28ng/mL, 소세포폐암은 0.20ng/mL, 그리고 대조군은 0.34ng/mL로서 세군간의 유의한 차이는 관찰되지 않았다. 또한 폐암의 임상병기에 따른 p53의 농도에는 어떤 상관성도 발견할 수 없었다. 폐암조직에 대한 p53 면역화학염색상 50%의 양성율을 보였으나 혈청학적 검사와는 어떤 상관성을 볼 수 없었다. 결 론: 결론적으로 본 연구의 변이 p53단백에 대한 혈청학적 검사는 폐암에 대한 진단적 가치는 없는 것으로 생각된다. 또한 원발성 폐암의 p53 변이를 확인하기 위한 조직면역화학염색은 50%에서 양성을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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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.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1993년도 제27차 학술대회 초록집
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• pp.83-83
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• 1993

정상 p53 유전자는 17번 염색체의 short arm에 위치하는 항암 유전자이나 point mutation에 의한 p53 유전자의 변이는 반감기가 긴 p53단백을 합성하여 핵내에 축적되고 변이형 p53은 암의 발생을 일으키는 것으로 알려졌다. 최근 p53에 대한 단크론성 항체가 개발되어 조직에서 변이형 p53의 검색이 가능하여 여러종류의 종양조직에서 면역세포화학적 방법으로 p53에 대한 표현 양상이 연구되었다. 이에 설 및 편도의 편평상피세포암 조직에서 면역세포화학적 방법으로 p53의 표현 양상을 검색하고 p53의 표현 양상과 임상적, 병리적 소견과의 관계를 알아보고자 29례의 편평상피세포암(설암 19례, 편도암 10례)의 진단시 채취한 생검조직에서 p53에 대한 단크론성 항체를 사용하여 p53의 표현양상과 병리조직학적 분화도, 종양의 원발부위, 원발종양의 크기, 경부 임파전이 여부와의 관계를 비교 분석하여 다음과 같은 결과를 얻었다. 1. p53은 대조군과 실험군의 모든 비종양핵에서는 음성반응을 보였고, 29례의 실험군 중 4례의 종양핵에서 양성반응을 보여 양성율은 13.8%이었다. 2. p53의 양성반응은 종양의 크기가 4cm 이상인 예에서 4cm 미만인 예에서 보다 양성인 예가 많았다(p<0.05). 3. p53의 양성반응은 종양의 병리조직학적 분화도, 종야의 원발부위, 경부 임파전이 여부와 유의한 관계가 없었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9603-9606
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• 2014

Background: Endometrial cancer is the fourth most common cancer among women in developed countries. Patients with endometrial cancer may benefit from systemic chemotherapy alone or in combination with targeted therapies if the disease is clinically diagnosed prior to spread and metastasis to other organs. The aim of this study was to evaluate the prognostic role of p53 polymorphism and its correlation with tumor grade in human uterine endometrial carcinomas. Materials and Methods: A total of 75 patients with endometrial carcinomas were studied for possible mutations in exon 4 of the p53 gene using polymerase chain reaction and restricting fragment length polymorphism techniques and sequencing. Results: In recent study, The rate of homozygote genotype of pro/pro or Arg/Arg in high grade group was higher than in comparison with low grade one. In addition samples that were undigested in RFLP, showed mutation in exone 4. Conclusions: Our findings showed that high grade endometrial carcinomas are highly associated with TP53 polymorphisms in comparison with low grades.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.21-21
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• 1996

The hyperthermostable protein, rubredoxin from Pyrococcus furiosus is 53-residue protein with a three-stranded anti-parallel $\beta$-sheet and several loops. To investigate the effect of changes of electrostatic and hydrophobic interactions on the structure and dynamic property of P. furiosus rubredoxin, molecular dynamics simulations in water were performed on three mesophilic rubredoxins, P, furiosus rubresoxin, and 5 mutants of P. furiosus rubredoxin. (omitted)

• Journal of Gastric Cancer
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• 제4권3호
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• pp.169-175
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• 2004

Purpose: The tumor suppressor gene p53 has been shown to be a factor in the carcinogenesis or progression of gastric cancer. The mutant p53 has been reported to cause a higher risk of lymph-node metastasis. Futhermore, mutation of the p53 has been linked to a poor prognosis for gastric cancer. The heat shock protein-27 (HSP27), a stress protein, has also been reported to be a poor prognostic factor in ovarian and breast cancers. However, in gastric-cancer patients, controversies exist as to its influence on the prognosis. In the present study, we used an immunohistochemical stain to observe the effects of p53 and HSP27 on the clinicopathological factors and on the prognosis for gastric-cancer patients. Materials and Methods: To evaluate the significance of p53 and HSP27 in gastric cancer patients, we analyzed 212 cases of gastric cancer (stage I.IV). Tissue samples of 212 patients were stained immunohistochemically for the mutant p53 protein and for HSP27. The correlations between protein expression and the clinicopathological factors were investigated. Results: The overall expression rates for p53 and HSP27 were $36.9\%\;and\;27.8\%$, respectively. p53 and HSP27 were correlated to each other because the HSP27 expression rate was higher in the p53-positive group (P=0.046). Statistically, the p53 and the HSP27 expression rates were significantly increased in the case of tumor invasiveness, lymphatic metastasis and vessel involvement. Therefore, they play a role in cancer progression. The 5-year survival rates of the p53-positive and the p53-negative groups were $62.8\%\;and\;60.1\%$, respectively (P=0.793) while the 5-year survival rates for the HSP27-positive and HSP27-negative groups were $54.2\%\;and\;63.1\%$, respectively (P=0.090). Conclusion: p53 and HSP27 were correlated to each other in our immunohistochemical study of gastric carcinomas and they were not independent prognostic factors in gastric- cancer patients. However, further studies are needed to determine their prognostic values for gastric-cancer patients.

• 대한두경부종양학회지
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• 제18권1호
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• pp.23-29
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• 2002

Mutation of the P53 tumor suppressor gene playa major role in the development of many carcinomas, namely in the colon, breast and bladder, whereas the role played by such mutations in thyroid carcinogenesis remains controversial. Vascular endothelial growth factor (VEGF) induces proliferation of endothelial cells, stimulates angiogenesis, and increases vascular permeability. Increased VEGF expression has been associated with poor clinical outcomes in many malignancies E-cadherin, a calcium-dependent transmembrane glycoprotein, is an adhesion molecule Expression of p53, VEGF and E-cadherin was assessed immunohistochemically in 19 tall columnar variant of papillary carcinoma, 24 common papillary carcinoma and 7 follicular carcinoma. The aim of this study was to evaluate the expression of P53,VEGF and E-cadherin as a potential maker for the prognosis of thyroid carcinomas. The results are as follows: 1) There were no significance in any clinical parameters examined among tall columnar variant of papillary carcinoma, common papillary carcinoma and follicular carcinoma. 2) The expression of P53 demonstrated low in tall columnar variant of papillary carcinoma, common papillary carcinoma and follicular carcinoma, but a significantly high in regional lymph node metastasis. 3) The expression of VEGF demonstrated a significantly high in regional lymph node metastasis than those without metastasis in papillary thyroid carcinoma. 4) The expression of E-cadherin demonstrated less often among papillary carcinomas with lymph node metastasis than in those without metastasis in papillary thyroid carcinoma. In conclusion, it is suggested that VEGF and E-cadherin will be useful for the diagnosis of thyroid carcinoma and serves as a biological marker for thyroid carcinoma lymph node metastasis.

• 대한임상검사과학회지
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• 제39권3호
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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.