• The Korean Journal of Physiology and Pharmacology
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• 제24권3호
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• pp.203-212
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• 2020

Promyelocytic leukemia (PML) gene, through alternative splicing of its C-terminal region, generates several PML isoforms that interact with specific partners and perform distinct functions. The PML protein is a tumor suppressor that plays an important role by interacting with various proteins. Herein, we investigated the effect of the PML isoforms on oncostatin M (OSM)-induced signal transducer and activator of transcription-3 (STAT-3) transcriptional activity. PML influenced OSM-induced STAT-3 activity in a cell type-specific manner, which was dependent on the p53 status of the cells but regardless of PML isoform. Interestingly, overexpression of PML exerted opposite effects on OSM-induced STAT-3 activity in p53 wild-type and mutant cells. Specifically, overexpression of PML in the cell lines bearing wild-type p53 (NIH3T3 and U87-MG cells) decreased OSM-induced STAT-3 transcriptional activity, whereas overexpression of PML increased OSM-induced STAT-3 transcriptional activity in mutant p53-bearing cell lines (HEK293T and U251-MG cells). When wild-type p53 cells were co-transfected with PML-IV and R273H-p53 mutant, OSM-mediated STAT-3 transcriptional activity was significantly enhanced, compared to that of cells which were transfected with PML-IV alone; however, when cells bearing mutant p53 were co-transfected with PML-IV and wild-type p53, OSM-induced STAT-3 transcriptional activity was significantly decreased, compared to that of transfected cells with PML-IV alone. In conclusion, PML acts together with wild-type or mutant p53 and influences OSM-mediated STAT-3 activity in a negative or positive manner, resulting in the aberrant activation of STAT-3 in cancer cells bearing mutant p53 probably might occur through the interaction of mutant p53 with PML.

• Journal of Gastric Cancer
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• 제1권1호
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• pp.10-16
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• 2001

Purpose: The p53 protein is a tumor supressor gene, and its mutation is associated with biologic aggressiveness. CD44v6, one of the CD44 family, is a cell surface glycoprotein that plays a role in cancer invasion and metastasis. Vascular endothelial growth factor (VEGF) is another recently identified growth factor with significant angiogenic properties. The purpose of this study was to investigate p53, CD44v6, and VEGF expressions to determine whether degree of expression was related to pathological parameters such as Lauren's classification, depth of invasion, and lymph node metastasis. Materials and Methods: Immunohistochemical stains of p53, CD44v6, and VEGF in formalin-fixed paraffin-embedded tissue sections of 125 gastric adenocarcinomas were done. Results: The overall expression rates of p53, CD44v6, and VEGF were $54.4\%$ (68/125), $36.8\%$ (46/125), and $48.0\%$ (60/125), respectively. The p53, not CD44v6 and VEGF was higher in intestinal-type gastric carcinomas by Lauren's classification. The expressions of p53, CD44v6, and VEGF were statistically correlated with depth of tumor invasion. The expression of CD44v6 was higher in the lymph node metastatic group than in the negative group. The p53 expression was significantly associated with VEGF expression. Conclusions: These data suggest that the expressions of p53, CD44v6, and VEGF are biologically related to malignancy. The p53 and CD44v6 expressions are independent; however, p53 gene mutation is one of the contributing factors to VEGF expression in gastric adenocarcinoma.

• Radiation Oncology Journal
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• 제17권1호
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• pp.70-77
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• 1999

목적 : 연구자들은 배양 배지의 산성환경이 SCK 선암세포에서 apoptosis를 유도하는 것과 산성환경이 SCK 선암 세포주에서 방사선에 의해 유도되는 apoptosis를 억제시킨다고 관찰하고 apoptosis 관련 유전자들인 p53, p21/WAF/CIP, Bcl-2 및 Bax 들의 발현과 배양 배지 pH 환경과의 연관성을 관찰하였다. 대상 및 방법 : SCK 선암 세포주를 체외 방사선 조사기를 이용하여 방사선 120Gy 조사 후 규정된 시간에 DNA fragmentation을 전기 영동으로 관찰하였다. 실험 조작으로 apoptosis가 유발된 세포군을 정량적으로 분석하고 세포주기 분석을 위하여 FACScan을 이용하였다. Apoptosis 관련 유전자들인 p53, P21/WAF/CIP, Bcl-2 및 Bax 들의 발현은 western blot으로 관찰하였다. 결과 : SCK 선암 세포주에서 방사선에 의해 유도되는 apoptosis는 산성환경(pH 6.6)에서는 apoptosis의 유발이 억제 된다는 사실을 관찰할 수 있었다. 세포주기 분석에서는 방사선조사 후 apoptosis가 뚜렷히 관찰된 pH 7.5 배양 배지 조건에 비하여 pH 6.6 배양 배지 조건에서 현저한 G2/M arrest가 관찰 되었다. apoptosis 관련 유전단백 분석에서는 Bcl-2 유전단백은 두 군 공히 발현의 차이를 관찰할 수 없었고, p53 및 p21은 pH 7.5 배양 배지 환경에서 뚜렷한 발현의 증가를 관찰하였고, p21은 pH 6.6 배양 배지 환경에서는 발현을 관찰할 수 없었다. Bax는 pH 7.5 배양 배지 환경에서 pH 6.6 환경에 비해 경미한 발현의 증가 및 지속성을 관찰하였다. 결론 . 저자들은 SCK 선암 세포주를 대상으로 방사선조사 후 상이한 pH 7.5 와 6.6의 배양 배지 조건에 따른 apoptosis의 관찰에 영향을 주는 유전자 발현에 관한 연구에서 Bcl-2 family의 발현에 비해 세포주기 관련 유전단백들인 p53 발현과 이에 따른 p21의 발현차이가 확연한 p53-dependent apoptotic pathway를 확인하였다. 방사선 조사 후 pH 6.6의 배양 배지 조건에서의 apoptosis 현상을 관찰할 수 없었던 이유는 pH 6.6의 경우 50-60$\%$의 세포가 G2/M arrest에서 세포주기를 순환하지 못함을 확인하였기에 G2/M arrest의 해지와 더불어 순환되는 세포주기의 결과에 따른 post-mitotic apoptosis 현상의 장애로 추론하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.91-96
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• 2013

Background: p53 alterations have been implicated in the development of many cancers, such as gastric cancer, but there is no evidence of p53 intron alterations in gastritis lesions. The aim of this study was to investigate the p53 intron alterations in gastritis along with p53 and mismatch repair protein expression and microsatellite status. Materials and Methods: PCR-sequencing was conducted for introns 2-7 on DNA extracted from 97 paired samples of gastritis lesions and normal adjacent tissue. Abnormal accumulation of p53 and mismatch repair proteins was investigated using immunohistochemistry. In addition, microsatellite status was evaluated with reference to five mononucleotide markers. Results: Gastritis cases included 41 males and 56 females in the age range of 15-83 years, 87.6% being H.pylori positive. IVS2+38, IVS3ins16 and IVS7+72 were the most polymorphic sites. Their minor allele frequency values were as follows: 0.38, 0.21 and 0.06, respectively. Samples with GG genotype at IVS2+38 and CT at IVS7+72 had no insertion. Moreover, most of the stable samples (91.9 %) had a G allele at IVS2+38. All of the samples were IHC negative for p53 protein, microsatellite stable and expressed mismatch repair proteins. p53 alterations were prominent in the H. Pylori+ group, but without statistical significance. Conclusions: According to our results, some p53 polymorphisms such as IVS2+38, IVS3ins16 and IVS7+72, because of their correlations together or with microsatellite status may contribute to gastritis development. However, so far effects on p53 expression and function remain unclear. Therefore, a comprehensive survey is needed to delineate their biological significance.

• Toxicological Research
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• 제20권1호
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• pp.21-29
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• 2004

We used cDNA microarray to assess gene expression profiles in hematopoetic cell line, U-937, exposed to low doses of ionizing irradiation. The 1,000 DNA elements on this array were PCR-amplified cDNAs selected from named human cancer related genes. According to the strength of irradiation, the levels of some gene expression were increased or decreased as dose-dependent manner. The gene expressions of Tubulin alpha, protein kinase, interferon-alpha, -beta, -omega receptor and ras homolog gene family H were significantly increased. Especially, Tubulin gene was shown 2.5 fold up-regulated manner under stress of 500 rad irradiation than 200 rad. On the other hand, fibroblast growth factor 12 and four and a half LIM domains, etc. were significantly down-regu-lated. Also, tumor protein 53(TP53) related genes that p53 inducible protein, tumor protein 53-binding protein looks of little significance as radiation sensitive manner. The radio-sensitivity of tubulin gene etc. that we proposed could be useful to rapid and correct survey for the bio-damage by exposure to low dose irradiation.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4609-4615
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• 2014

Background: To investigate tumor inhibition effects and mechanisms of Angelica sinensis and Sophorae flavescentis ait decoction (ASSF) combined with diamine-dichloroplatinum (DDP). Materials and Methods: Bodyweight, tumor inhibition rate and q value were calculated for single ASSF or ASSF combined with DDP on H22 carcinoma xenograft KM mice. Biochemical methods for serum LDH, AST, ALT, and AKP, ELISA method for serum HIF-$1{\alpha}$, pathological assessemnt of thymus, immunohistochemistry detection of tumor tissue caspase3 and mutant p53 protein, and qRT-PCR detection of bax/ bcl-2 mRNA were applied. Results: Compared with DDP control group, the bodyweight increased in ASSF-DDP group (p<0.01). Tumor inhibition rates for DDP, ASSF, ASSF-DDP were 62.7%. 43.7% and 71.0% respectively, with a q value of 0.90. Compared with other groups, thymus of DDP control group had obvious pathological injury (p<0.01), serum LDH, AST, ALT, AKP increased significantly in DDP control group (p<0.01), while serum HIF-$1{\alpha}$ was increased in the model control group. Compared with this latter, the expression of mutant p53 protein and bcl-2 mRNA were decreased in all treatment groups (p<0.01), but there were no statistical difference between DDP control p and ASSF-DDP groups. The expression of caspase3 protein and bax mRNA was increased in all treatment groups, with statistical differences between the DDP and ASSF-DDP groups (p<0.01). Conclusions: ASSF can inhibit bodyweight decrease caused by DDP, can inhibit tumor growth synergistically with DDP mainly through increasing serum HIF-$1{\alpha}$ and pro-apoptotic molecules such as caspase 3 and bax, rather than through decreasing anti-apoptotic mutant p53 and bcl-2. ASSF can reduce DDP toxicity due to decreasing the release of LDH, AST, ALT, AKP into blood and enhancing thymus protection.

• Tuberculosis and Respiratory Diseases
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• 제53권3호
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• pp.275-284
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• 2002

연구배경: Gemcitabine은 폐암에서 임상적 유용성이 큰 새로운 항암제이다. 저자들은 폐암세포에서 Gemcita bine에 의한 세포 사멸과 p53의 역할을 규명하고자 하였다. 방 법 : 폐암 세포주로 A549와 H358 세포주를 이용하였고 세포 독성 검사는 MTT assay를 이용하였으며 Gemcitabine 농도는 10nM, 100nM, 1uM, 10uM, 100uM을 사용하였다. 세포 주기 검사는 FACScan을 이용하여 분석하였고 p53 활성화 여부는 western blot을 사용하였다. p53 단백질 분해를 촉진시키는 안정적 세포주 A549-E6과 H358-E6을 제조하고 대조 세포주 A549-neo와 H358-neo 세포주와 비교하여 p53의 기능적 knock-out 실험을 시행하였다. p53의 기능적 knock-out은 p53 유도 약제인 doxorubicine 1 M을 사용하여 western blot으로 확인하였다. 결 과 : A549와 H358 세포주에서 Gemcitabine은 농도에 비례한 세포 독성을 보였고 S phase arrest와 p53의 활성화를 유도하였다. 안정적 세포주 A549-E6과 H358-E6은 MTT assay에서 대조 세포주 A549-noo와 H358-noo에 비해 각각 20-30%, 30-40%의 세포 독성 차단효과를 보였다. 결 론 : Gemcitabine은 S phase arrest를 유발시키고 p53 단백질의 활성화를 유도하며 p53의 기능소실이 Gemcitabine에 대한 저항인자로 작용하고 있음을 확인할 수 있었다. 향후 Gemcitabine에 의해 p53의 활성화가 발생하는 신호경로와 p53 활성화에 의한 아포프토시스의 신호경로에 대한 연구가 필요할 것으로 사료된다.

• Journal of Korean Neurosurgical Society
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• 제38권4호
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• pp.293-298
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• 2005

Objective : The authors investigate the spatial characteristics of apoptotic genes expressed around the focal cerebral infarction, and attempted to explain the penumbra with them. Methods : A delayed focal cerebral infarction was created in twelve adult Sprague-Dawley rats. We performed the immunohistochemical staining for the apoptosis, bcl-2 and p53 proteins and measured the local cerebral blood flow [CBF] at the infarction core area and peri-infarct area pre- and intra-operatively. The peri-infarct area was divided into six sectors by distance from the infarction border. Results : The size [$mm^2$] of apoptosis, bcl-2, and p53 areas were $3.1{\pm}1.2$, $4.7{\pm}2.1$, and $6.8{\pm}2.4$, respectively. Apoptosis, bcl-2 or p53 positive cells were concentrated at the peri-infarct area adjacent to the infarction core. Their numbers reduced peripherally, which was inversely proportional to the local CBF. The p53 area seems to overlap with and larger than the ischemic penumbra. Conclusion : The p53 positive area provides a substitutive method defining the penumbra under the molecular base of knowledge.

• Molecules and Cells
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• 제38권4호
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• pp.312-317
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• 2015

Depletion of intracellular zinc by N,N,N,N-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) induces p53-mediated protein synthesis-dependent apoptosis of mouse cortical neurons. Here, we examined the requirement for poly(ADP-ribose) polymerase (PARP)-1 as an upstream regulator of p53 in zinc depletion-induced neuronal apoptosis. First, we found that chemical inhibition or genetic deletion of PARP-1 markedly attenuated TPEN-induced apoptosis of cultured mouse cortical neurons. Poly(ADP-ribosyl)ation of p53 occurred starting 1 h after TPEN treatment. Suggesting the critical role of PARP-1, the TPEN-induced increase of stability and activity of p53 as well as poly(ADP-ribosyl)ation of p53 was almost completely blocked by PARP inhibition. Consistent with this, the induction of downstream pro-apoptotic proteins PUMA and NOXA was noticeably reduced by chemical inhibitors or genetic deletion of PARP-1. TPEN-induced cytochrome C release into the cytosol and caspase-3 activation were also blocked by inhibition of PARP-1. Taken together, these findings indicate that PARP-1 is essential for TPEN-induced neuronal apoptosis.

• 대한화학회지
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• 제47권5호
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• pp.460-465
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• 2003

p53 유전자의 변이는 다양한 인체암 중 가장 일반적인 유전자적 변화로 알려져 있으며, 양성에서 악성 대장암으로 전이되는 과정에서 연관이 있는 것으로 알려져 있다. 본 연구에서는 PCR-SSCP와 DHPLC를 이용하여 대장암 환자의 조직에서 p53 유전자의 엑손 5-8에서 돌연변이를 분석하였다. SSCP에서는 50개의 샘플중 엑손 5에서 C13109>T 형태의 돌연변이가 7례가(14%) 발견되었고, DHPLC에서는 C13109>T 7례와 C13202>A, C13204>G 형태의 돌연변이 2례, 모두 9례의(18%) 변이가 검출되었다. DHPLC 분석법을 이용하여 SSCP에서 발견하지 못했던 2례(4%)의 변이를 더 발견하였다. 최종적으로 염기서열분석법을 통해 위의 결과를 확인하였고, p53 돌연변이 검출법으로 SSCP보다 DHPLC가 더 감도가 좋고 효과적인 검출법임을 확인하였다.