• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.453-465
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• 2000

Background : Lung carcinogenesis is a multistage process involving alterations in multiple genes and diverse pathway. Mutational activation of oncogenes and inactivation of tumor suppressor genes, and subsequent increased genetic instability are the major genetic events. The p53 gene and FHIT gene as tumor suppressor genes contribute to the pathogenesis of lung cancer, evidenced by mutation, microsatellite instability(MI) and loss of heterozygosity(LOH). Methods : We analysed genetic mutations of p53 and FHIT gene in 29 surgical specimens of nonsmall cell lung cancer using PCR-single strand conformation polymorphism, DNA sequencing and RT-PCR. MI and LOH were analyzed in loci of D3S1285, D9S171, and TP53. Results : In 2 cases, point mutation of p53 gene was observed on exon 5. MI of 3 times and LOH of 14 times were observed in at least one locus. In terms of the location of microsatellite, D3S1285 as a marker of FH1T was observed in 5 cases out of 26 specimens; D9S171 as a marker of p16 in 5 out of 17; and TP53 as a marker of p53 in 7 out of 27. In view of histologic type, squamous cell carcinoma presented higher frequency of microsatellite alteration, compared to others. Mutation of FHIT gene was observed in 11 cases and 6 cases of those were point mutation as a silent substitution on exon 8. FHIT mRNA expression exhibited deletion on exon 6 to 9 in 4 cases among 15 specimens, presenting beta-actin normally. Conclusion : Our results show comparable frequency of genetic alteration in nonsmall cell lung cancer to previous studies of Western countries. Microsatellite analysis might have a role as a tumor marker especially in squamous cell carcinoma. Understanding molecular abnormalities involved in the pathogenesis could potentially lead to prevention, earlier diagnosis and the development of novel investigational approaches to the treatment of lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2971-2974
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• 2015

TP53 is assumed to be a very important tumour suppressor gene, as illustrated by recent reports that have shown effects of its polymorphisms on breast cancer risk. Arg72Pro and PIN3(16bp duplication) polymorphisms are proposed to have an effective role in structural changes of p53 and have therefore attracted interest as a risk factor for breast cancer in different populations. The aim of this study was to examine and determine whether p53 codon 72 and PIN3 Ins16 bp may be associated with an increased risk for breast cancer in female patients from the northwest of Iran. Genotyping was performed by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) method for a total of 100 women with breast cancer and 100 healthy women without any background of cancer, focusing on the TP53 Arg72Pro-16Del/Ins haplotypes and the combined genotypes. The results in this study established no statistical significant distinctions between the genotypes and a llele frequency were found for Arg72Pro and PIN3 Ins 16 bp polymorphisms between patients and controls.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4059-4062
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• 2016

Frequencies of polymorphisms of genes BRCA1 and ТР53 in breast cancer (BC) patients with a BC family history and radiation history were assessed and compared in the Semey region of Kazakhstan. The study included 60 women directly irradiated by the activities of the Semipalatinsk test site with a calculated effective equivalent dose of 500 mSv and their first generation descendants (group BC+Her+Exp); 65 women with family BC and absence of radiological history - the effective equivalent dose due to anthropogenic sources not exceeding 50 mSv (group BC+Her-Exp). The comparison group consisted of 65 women patients with breast cancer without family and radiological history (BC-Her-Exp). The control group comprised 60 women without breast cancer and without family and radiological history (nonBC). We carried out the genotyping of the polymorphisms c.2311T>C, c.4308T>C and 5382insC of the BRCA1 gene and rs1042522 of the ТР53 gene. The frequency of the polymorphism c.2311T>C was significantly higher in patients of the group BC+Her+Exp than in healthy women, and of the polymorphism 5382insC in BC+Her+Exp compared to all other groups. The frequency of the rs1042522 polymorphism of ТР53 was significantly higher in all groups of patients with breast cancer compared with the control group. Differences between groups of women with breast cancer were significant only in BC+Her+Exp vs. BC+Her-Exp. Combinations of polymorphisms of the genes BRCA1 and TP53 predominated in women with a family and radiological history.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.134-142
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• 2020

This study aimed to determine whether there was a difference in lung functions of smokers according to the presence of carcinogenic genetic-metabolizing enzymes by comparing the results of lung functions and the presence of genetic metabolizing enzymes that metabolize tobacco substances. To achieve this, 31 smokers without no illness and no psychiatric history were selected (28 males and 3 females); they were aged 20 to 27 years and were physically and mentally healthy students attending K University. Their lung functions were measured, and gene polymorphisms of cytochrome P-450 1A1 (CYP1A1) related to metabolic activation of tobacco components and gene polymorphism of tumor protein 53 (TP53) related to lung cancer were analyzed. As a result, the mean values of lung function of TT and Arg / Arg without genetic mutations were the highest, and ANOVA analysis of CYP1A1 and lung functions showed that the P-value of FVC was 0.049, which was different between groups. In other words, there is no high mutation in Cytochrome P-450 1A1 (CYP1A1) gene, which is associated with the metabolic activation of tobacco components. In other words, In the absence of the mutant Cytochrome P-450 1A1 (CYP1A1) gene, which is associated with the metabolic activation of tobacco components, the value of FVC was high.

• Genomics & Informatics
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• v.14 no.3
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• pp.78-84
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• 2016

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NKTCL), is a malignant disorder of cytotoxic lymphocytes of NK or T cells. It is an aggressive neoplasm with a very poor prognosis. Although extranodal NKTCL reportedly has a strong association with Epstein-Barr virus, the molecular pathogenesis of NKTCL has been unexplored. The recent technological advancements in next-generation sequencing (NGS) have made DNA sequencing cost- and time-effective, with more reliable results. Using the Ion Proton Comprehensive Cancer Panel, we sequenced 409 cancer-related genes to identify somatic mutations in five NKTCL tissue samples. The sequencing analysis detected 25 mutations in 21 genes. Among them, KMT2D, a histone modification-related gene, was the most frequently mutated gene (four of the five cases). This result was consistent with recent NGS studies that have suggested KMT2D as a novel driver gene in NKTCL. Mutations were also found in ARID1A, a chromatin remodeling gene, and TP53, which also recurred in recent NGS studies. We also found mutations in 18 novel candidate genes, with molecular functions that were potentially implicated in cancer development. We suggest that these genes may result in multiple oncogenic events and may be used as potential bio-markers of NKTCL in the future.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3503-3507
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• 2013

Background: Although the majority of investigations concerned with TP53 and its protein have focused on coding regions, recently a set of studies highlighted significant roles of regulatory elements located in p53 mRNA, especially 5'UTR. The wrap53${\alpha}$ transcript is one of those that acts as a natural antisense agent, forming RNA-RNA hybrids with p53 mRNA and protecting it from degradation. Materials and Methods: In this study, we focused on the mutation status of exon $1{\alpha}$ of the WRAP53 gene (according to exon 1 of p53) in 160 breast tumor tissue samples and conducted a bioinformatics search for probable miRNA binding site in the p53/wrap53 overlapping region. Mutations were detected, using single stranded conformation polymorphism (SSCP) and sequencing. We applied the miRBase database for prediction of miRNAs which target overlapping region of p53/wrap53 transcripts. Results: Our results showed all samples to have wild type alleles in exon 1 of TP53 gene. We could detect a novel and unreported intronic mutation (IVS1+56, G>C) outside overlapping regions of p53/wrap53 genes in breast cancer tissues and also predict the presence of a binding site for miR-4732-5p in the 5'UTR of Wrap53 mRNA. Conclusions: From our findings we propose designing further studies focused on overexpression of miRNA-4732-5p and introducing different mutations in the overlapping region of wrap53 and p53 genes in order to study their effects on p53 and its ${\Delta}N$ isoform (${\Delta}$40p53) expression. The results may provide new pieces in the p53 targeting puzzle for cancer therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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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.

• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.246-251
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• 2022

Li-Fraumeni syndrome (LFS) is an inherited autosomal-dominant tumor-predisposition disorder caused by germline mutations in the TP53 tumor suppressor gene. Since patients with LFS are likely to develop therapy-related cancers, radiation therapy should be avoided if breast cancer is found in these individuals. Herein, we present a case of secondary breast cancer in an LFS patient after radiation and chemotherapy for the first diagnosed breast sarcoma.

• Molecules and Cells
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• v.43 no.1
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• pp.23-33
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• 2020

NF-κB signaling through both canonical and non-canonical pathways plays a central role in immune responses and inflammation. NF-κB-inducing kinase (NIK) stabilization is a key step in activation of the non-canonical pathway and its dysregulation implicated in various hematologic malignancies. The tumor suppressor, p53, is an established cellular gatekeeper of proliferation. Abnormalities of the TP53 gene have been detected in more than half of all human cancers. While the non-canonical NF-κB and p53 pathways have been explored for several decades, no studies to date have documented potential cross-talk between these two cancer-related mechanisms. Here, we demonstrate that p53 negatively regulates NIK in an miRNA-dependent manner. Overexpression of p53 decreased the levels of NIK, leading to inhibition of the non-canonical NF-κB pathway. Conversely, its knockdown led to increased levels of NIK, IKKα phosphorylation, and p100 processing. Additionally, miR-34b induced by nutlin-3 directly targeted the coding sequences (CDS) of NIK. Treatment with anti-miR-34b-5p augmented NIK levels and subsequent non-canonical NF-κB signaling. Our collective findings support a novel cross-talk mechanism between non-canonical NF-κB and p53.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2699-2705
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• 2014

This study was to undertaken to investigate the impacts of AhR, CYP1A1, GSTM1 genetic polymorphisms on the R273G mutation in exon 8 of the tumor suppressor p53 gene (TP53) among polycyclic aromatic hydrocarbons (PAHs) exposed to coke-oven workers. One hundred thirteen workers exposed to PAH and 82 control workers were recruited. We genotyped for polymorphisms in the AhR, CYP1A1, GSTM1, and TP53 R273G mutation in blood by PCR methods, and determined the levels of 1-hydroxypyrene as PAH exposure marker in urine using the high pressure liquid chromatography assay. We found that the distribution of alcohol users and the urinary excretion of 1-OHP in the exposed workers were significantly higher than that of the control workers (p=0.004, p<0.001, respectively). Significant differences were observed in the p53 genotype distributions of smoking subjects (p=0.01, 95%CI: 1.23-6.01) and PAH exposure (p=0.008, 95%CI: 1.24-4.48), respectively. Further, significant differences were observed in the p53 exon 8 mutations for the genetic polymorphisms of Lys/Arg for AhR (p=0.02, 95%CI: 0.70-15.86), Val/Val for CYP1A1 (p=0.04, 95%CI: 0.98-19.09) and null for GSTM1 (p=0.02, 95%CI: 1.19-6.26), respectively. Our findings indicated that polymorphisms of PAH metabolic genes, such as AhR, CYP1A1, GSTM1 polymorphisms may interact with p53 genetic variants and may contribute to PAH related cancers.