• BMB Reports
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• v.34 no.1
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• pp.73-79
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• 2001

Transcriptional activation domains are known to be inherently "unstructured" with no tertiary structure. A recent NMR study, however, has shown that the transactivation domain in human p53 is populated with an amphipathic helix and two nascent turns. This suggests that the presence of such local secondary structures within the overall "unstructured" structural framework is a general feature of acidic transactivation domains. These pre-existing local structures in p53, formed selectively by positional conserved hydrophobic residues that are known to be critical for transcriptional activity, thus appear to constitute the specific structural motifs that regulate recognition of the p53 transactivation domain by target proteins. Here, we report the results of a NMR structural comparison between the native human p53 transactivation domain and an inactive mutant (22L,23W$\rightarrow$22R,23S). Results show that the mutant has an identical overall structural topology as the native protein, to the extent that the amphipathic helix formed by the residues 18T 26L within the native p53 transactivating domain is preserved in the double mutant. Therefore, the lack of transcriptional activity in the double mutant should be ascribed to the disruption of the essential hydrophobic contacts between the p53 transactivation domain and target proteins due to the (22L,23W$\rightarrow$22R,23S) mutation.

• Journal of Life Science
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• v.20 no.2
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• pp.213-218
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• 2010

In the present study, we investigated anti-proliferative activities of capsaicin and gene expression changes in response to capsaicin treatment in human colorectal HCT116 cells. The results showed that capsaicin decreased cell viabilities in a dose dependent manner and induced global gene expression changes. We found that 103 genes were up-regulated more than twofold, whereas 153 genes were down-regulated more than twofold by $100\;{\mu}M$ capsaicin treatment. Among the up-regulated genes, we selected 4 genes (NAG-1, DDIT3, GADD45A and PCK2) and performed RT-PCR to confirm the microarray data. We found that $100\;{\mu}M$ of capsaicin increased tumor suppressor p53 gene expression. In addition, the results showed that NAG-1, DDIT3 and GADD45A expressions were not dependent on p53 presence, whereas PCK2 expression. The results of this study may help to increase our understandings of the molecular mechanism of anti-proliferative activity mediated by capsaicin in human colorectal cancer cells.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.452-459
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• 2012

This study was conducted in order to investigate the effect of resveratrol on the induction of apoptosis in MDA-MB-231 breast cancer cells. The result of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl terazolium bromide (MTT) assay shows that cell viability significantly decreased in a dose and time-dependent manner. 4',6-diamidino-2-phenylindole (DAPI) staining shows significantly increased chromatin condensation in a dose and time-dependent manner. Resveratrol increased the expression of p53, cleaved-caspase-3, and cleaved-caspase-9, whereas the expression of PI3K/Akt decreased in a time-dependent manner. We investigated the in vivo tumor growth inhibitory effect of resveratrol. Tumor volume was significantly decreased in the 50 mg/kg resveratrol-administration group compared to the control group. In the 50 mg/kg treated group. Apoptosis cells were frequently observed by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay. Immunohistochemistry staining shows increased the expression of p53, cytochrome-C, and cleaved-caspase-3 in the 50 mg/kg treated group. These results indicate that resveratrol induced apoptosis through PI3K/Akt and p53 signal pathway in MDA-MB-231 cell.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.915-921
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• 2012

Background: Previous studies investigating the association between TP53 Arg72Pro polymorphism and gastric cancer (GC) risk in Asian population have reported controversial results. Thus, a meta-analysis was performed. Methods: A comprehensive literature search was conducted and 17 case-control studies were finally included, involving a total of 5,990 GC cases and 6,812 controls. Subgroup analyses were performed by the sample size. Results: Meta-analysis of all 17 studies showed variant genotypes of TP53 Arg72Pro to be associated with an elevated GC risk in three genetic comparison models ($OR_{Pro\;vs.\;Arg}$=1.13, 95%CI 1.03-1.25, $P_{OR}$=0.01; $OR_{Homozygote\;comparison\;model}$=1.33, 95%CI 1.07-1.64, $P_{OR}$=0.009; $OR_{Dominant\;genetic\;model}$=1.13, 95%CI 1.05-1.22, $P_{OR}$=0.002). Besides, a more obvious association was observed after the heterogeneity was decreased (all P values less than 0.001). This association was further identified by both subgroup and sensitivity analyses. Conclusions: This meta-analysis suggests the Pro variant of TP53 Arg72Pro contributes to gastric cancer risk in Asians.

• Radiation Oncology Journal
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• v.35 no.4
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• pp.332-339
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• 2017

Purpose: This study aimed to evaluate the prognostic effects of lymphovascular invasion (LVI) in triple-negative breast cancer (TNBC) patients who underwent surgical resection. Materials and Methods: A total of 63 non-metastatic TNBC patients who underwent surgical resection were retrospectively investigated from 2007 to 2016 in Inje University Busan Paik Hospital. Pathological tests revealed that 12 patients (19.0%) had LVI. Approximately 61.9% (n = 39) of the patients' samples stained positive for p53. Additional chemotherapy and radiotherapy (RT) were performed in 53 (84.1%) and 47 (74.6%) patients, respectively. Results: The median follow-up period was 39.5 months (range, 5.9 to 123.0 months). The pathological T stage (p = 0.008), N stage (p = 0.014), and p53 positivity (p = 0.044) were associated with LVI. Overall, the 3-year disease-free survival (DFS) rate and overall survival (OS) rate were 85.4% and 90.2%, respectively. Ten patients (15.9%) experienced relapse. LVI (n = 12) was associated with relapses (p = 0.016). p53 positivity was correlated with poor DFS (p = 0.048). Furthermore, LVI was related to poor DFS (p = 0.011) and OS (p = 0.001) and considered as an independent prognostic factor for DFS (p = 0.039). The 3-year DFS of patients with LVI (n = 12) was only 58.3%. Adjuvant RT minimized the negative prognostic effect of LVI on DFS (p = 0.068 [with RT] vs. p = 0.011 [without RT]). Conclusion: LVI was related to the detrimental effects of disease progression and survival of TNBC patients. Thus, a more effective treatment strategy is needed for TNBC patients with LVI.

• 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.

• Bulletin of the Korean Mathematical Society
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• v.53 no.2
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• pp.569-579
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• 2016

L. Carlitz introduced higher order degenerate Euler polynomials in [4, 5] and studied a degenerate Staudt-Clausen theorem in [4]. D. S. Kim and T. Kim gave some formulas and identities of degenerate Euler polynomials which are derived from the fermionic p-adic integrals on ${\mathbb{Z}}_p$ (see [9]). In this paper, we introduce higher order degenerate Genocchi polynomials. And we give some formulas and identities of degenerate Genocchi polynomials which are derived from the fermionic p-adic integrals on ${\mathbb{Z}}_p$.

• BMB Reports
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• v.34 no.2
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• pp.123-129
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• 2001

Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2349-2354
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• 2012

Objective: Individual studies of the associations between P53 codon 72 polymorphism (rs1042522) and bladder cancer susceptibility have shown inconclusive results. To derive a more precise estimation of the relationship, we performed this systemic review and meta-analysis based on 15 publications. Methods: We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Results: We found that there was no association between P53 codon 72 polymorphism and bladder cancer risk in the comparisons of Pro/Pro vs Arg/Arg; Pro/Arg vs. Arg/Arg; Pro/Pro plus Pro/Arg vs. Arg/Arg; Arg/Arg vs. Pro/Arg plus Arg/Arg (OR=1.06 95%CI 0.81-1.39; OR=1.06 95%CI 0.83-1.36; OR=0.98 95%CI 0.78-1.23; OR=1.06 95%CI 0.84-1.32). However, a significantly increased risk of bladder cancer was found among Asians in the homozygote comparison (Pro/Pro vs. Arg/Arg, OR=1.36 95%CI 1.05-1.75, P=0.790 for heterogeneity) and the dominant model (Arg/Pro plus Pro/Pro vs. Arg/Arg, OR=1.26 95%CI 1.05-1.52, P=0.564 for heterogeneity). In contrast, no evidence of an association between bladder cancer risk and P53 genotype was observed among Caucasian population in any genetic model. When stratifying for the stage of bladder, no statistical association were found (Pro/Pro vs. Arg/Arg, OR=0.45 95%CI 0.17-1.21; Pro/Arg vs. Arg/Arg, OR=0.60 95%CI 0.28-1.27; Dominant model, OR=0.56 95%CI 0.26-1.20; Recessive model, OR=0.62 95%CI0.35-1.08) between P53 codon 72 polymorphism and bladder cancer in all comparisons. Conclusions: Despite the limitations, the results of the present meta-analysis suggest that, in the P53 codon 72, Pro/Pro type and dominant mode might increase the susceptibility to bladder cancer in Asians; and there are no association between genotype distribution and the stage of bladder cancer.