Gaining insights into the codon usage patterns of TP53 gene across eight mammalian species.

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Tarikul Huda Mazumder

Full Text Available TP53 gene is known as the "guardian of the genome" as it plays a vital role in regulating cell cycle, cell proliferation, DNA damage repair, initiation of programmed cell death and suppressing tumor growth. Non uniform usage of synonymous codons for a specific amino acid during translation of protein known as codon usage bias (CUB is a unique property of the genome and shows species specific deviation. Analysis of codon usage bias with compositional dynamics of coding sequences has contributed to the better understanding of the molecular mechanism and the evolution of a particular gene. In this study, the complete nucleotide coding sequences of TP53 gene from eight different mammalian species were used for CUB analysis. Our results showed that the codon usage patterns in TP53 gene across different mammalian species has been influenced by GC bias particularly GC3 and a moderate bias exists in the codon usage of TP53 gene. Moreover, we observed that nature has highly favored the most over represented codon CTG for leucine amino acid but selected against the ATA codon for isoleucine in TP53 gene across all mammalian species during the course of evolution.

Significance of TP53 Mutation in Wilms Tumors with Diffuse Anaplasia: A Report from the Children’s Oncology Group

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Ooms, Ariadne H.A.G.; Gadd, Samantha; Gerhard, Daniela S.; Smith, Malcolm A.; Guidry Auvil, Jaime M.; Meerzaman, Daoud; Chen, Qing-Rong; Hsu, Chih Hao; Yan, Chunhua; Nguyen, Cu; Hu, Ying; Ma, Yussanne; Zong, Zusheng; Mungall, Andrew J.; Moore, Richard A.; Marra, Marco A.; Huff, Vicki; Dome, Jeffrey S.; Chi, Yueh-Yun; Tian, Jing; Geller, James I.; Mullighan, Charles G.; Ma, Jing; Wheeler, David A.; Hampton, Oliver A.; Walz, Amy L.; van den Heuvel-Eibrink, Marry M.; de Krijger, Ronald R.; Ross, Nicole; Gastier-Foster, Julie M.; Perlman, Elizabeth J.

2016-01-01

Purpose To investigate the role and significance of TP53 mutation in diffusely anaplastic Wilms tumor (DAWT). Experimental Design All DAWTs registered on National Wilms Tumor Study-5 (n=118) with available samples were analyzed for TP53 mutations and copy loss. Integrative genomic analysis was performed on 39 selected DAWTs. Results Following analysis of a single random sample, 57 DAWT (48%) demonstrated TP53 mutations, 13(11%) copy loss without mutation, and 48(41%) lacked both (defined as TP53-wildtype (wt)). Patients with Stage III/IV TP53-wt DAWTs (but not those with Stage I/II disease) had significantly lower relapse and death rates than those with TP53 abnormalities. In-depth analysis of a subset of 39 DAWT showed 7(18%) to be TP53-wt: these demonstrated gene expression evidence of an active p53 pathway. Retrospective pathology review of TP53-wt DAWT revealed no or very low volume of anaplasia in 6/7 tumors. When samples from TP53-wt tumors known to contain anaplasia histologically were available, abnormal p53 protein accumulation was observed by immunohistochemistry. Conclusion These data support the key role of TP53 loss in the development of anaplasia in WT, and support its significant clinical impact in patients with residual anaplastic tumor following surgery. These data also suggest that most DAWTs will show evidence of TP53 mutation when samples selected for the presence of anaplasia are analyzed. This suggests that modifications of the current criteria to also consider volume of anaplasia and documentation of TP53 aberrations may better reflect the risk of relapse and death and enable optimization of therapeutic stratification. PMID:27702824

WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma.

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Zhukova, Nataliya; Ramaswamy, Vijay; Remke, Marc; Martin, Dianna C; Castelo-Branco, Pedro; Zhang, Cindy H; Fraser, Michael; Tse, Ken; Poon, Raymond; Shih, David J H; Baskin, Berivan; Ray, Peter N; Bouffet, Eric; Dirks, Peter; von Bueren, Andre O; Pfaff, Elke; Korshunov, Andrey; Jones, David T W; Northcott, Paul A; Kool, Marcel; Pugh, Trevor J; Pomeroy, Scott L; Cho, Yoon-Jae; Pietsch, Torsten; Gessi, Marco; Rutkowski, Stefan; Bognár, Laszlo; Cho, Byung-Kyu; Eberhart, Charles G; Conter, Cecile Faure; Fouladi, Maryam; French, Pim J; Grajkowska, Wieslawa A; Gupta, Nalin; Hauser, Peter; Jabado, Nada; Vasiljevic, Alexandre; Jung, Shin; Kim, Seung-Ki; Klekner, Almos; Kumabe, Toshihiro; Lach, Boleslaw; Leonard, Jeffrey R; Liau, Linda M; Massimi, Luca; Pollack, Ian F; Ra, Young Shin; Rubin, Joshua B; Van Meir, Erwin G; Wang, Kyu-Chang; Weiss, William A; Zitterbart, Karel; Bristow, Robert G; Alman, Benjamin; Hawkins, Cynthia E; Malkin, David; Clifford, Steven C; Pfister, Stefan M; Taylor, Michael D; Tabori, Uri

2014-12-24

TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6%±8.7%, respectively (p<0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89%±2% vs. 57.4%±1.8% (p<0.01)). In contrast, β-catenin mutation sensitized TP53 mutant cells to radiation (p<0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5%±1.5% in lithium treated cells vs. 56.6±3% (p<0.01)) accompanied by increased number of γH2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33%±8% for lithium treated cells vs. 27%±3% for untreated controls (p=0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.

The Relationship between TP53 Gene Status and Carboxylesterase 2 Expression in Human Colorectal Cancer

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Momoko Ishimine

2018-01-01

Full Text Available Irinotecan (CPT-11 is an anticancer prodrug that is activated by the carboxylesterase CES2 and has been approved for the treatment of many types of solid tumors, including colorectal cancer. Recent studies with cell lines show that CES2 expression is regulated by the tumor suppressor protein p53. However, clinical evidence for this regulatory mechanism in cancer is lacking. In this study, we examined the relationship between TP53 gene status and CES2 expression in human colorectal cancer. Most colorectal cancer specimens (70%; 26 of 37 showed lower CES2 mRNA levels (≥1.5-fold lower than the adjacent normal tissue, and only 30% (12 of 37 showed similar (<1.5-fold lower or higher CES2 mRNA levels. However, TP53 gene sequencing revealed no relationship between CES2 downregulation and TP53 mutational status. Moreover, while colorectal cancer cells expressing wild-type p53 exhibited p53-dependent upregulation of CES2, PRIMA-1MET, a drug that restores the transcriptional activity of mutant p53, failed to upregulate CES2 expression in cells with TP53 missense mutations. These results, taken together, suggest that CES2 mRNA expression is decreased in human colorectal cancer independently of p53.

TP53 mutation spectrum in smokers and never smoking lung cancer patients

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Ann Rita Halvorsen

2016-05-01

Full Text Available AbstractBackground: TP53 mutations are among the most common mutations found in lung cancers, identified as an independent prognostic factor in many types of cancers. The purpose of this study was to investigate the frequency and prognostic impact of TP53 mutations in never-smokers and in different histological subtypes of lung cancer.Methods: We analysed tumour tissue from 394 non-small cell carcinomas including adenocarcinomas (n=229, squamous cell carcinomas (n=112, large cell carcinomas (n=30 and others (n=23 for mutations in TP53 by the use of Sanger sequencing (n=394 and next generation sequencing (n=100. Results: TP53 mutations were identified in 47.2% of the samples, with the highest frequency (65% of mutations among squamous cell carcinomas. Among never-smokers, 36% carried a TP53 mutation, identified as a significant independent negative prognostic factor in this subgroup. For large cell carcinomas, a significantly prolonged progression free survival was found for those carrying a TP53 mutation. In addition, the frequency of frameshift mutations was doubled in squamous cell carcinomas (20.3% compared to adenocarcinomas (9.1%.Conclusion: TP53 mutation patterns differ between the histological subgroups of lung cancers, as also influenced by smoking history. This indicates that the histological subtypes in lung cancer are genetically different, and that smoking-induced TP53 mutations may have a different biological impact than TP53 mutations occurring in never-smokers.

TP53 and lacZ mutagenesis induced by 3-nitrobenzanthrone in Xpa-deficient human TP53 knock-in mouse embryo fibroblasts.

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Kucab, Jill E; Zwart, Edwin P; van Steeg, Harry; Luijten, Mirjam; Schmeiser, Heinz H; Phillips, David H; Arlt, Volker M

2016-03-01

3-Nitrobenzanthrone (3-NBA) is a highly mutagenic compound and possible human carcinogen found in diesel exhaust. 3-NBA forms bulky DNA adducts following metabolic activation and induces predominantly G:CT:A transversions in a variety of experimental systems. Here we investigated the influence of nucleotide excision repair (NER) on 3-NBA-induced mutagenesis of the human tumour suppressor gene TP53 and the reporter gene lacZ. To this end we utilised Xpa -knockout (Xpa-Null) human TP53 knock-in (Hupki) embryo fibroblasts (HUFs). As Xpa is essential for NER of bulky DNA adducts, we hypothesized that DNA adducts induced by 3-NBA would persist in the genomes of Xpa-Null cells and lead to an increased frequency of mutation. The HUF immortalisation assay was used to select for cells harbouring TP53 mutations following mutagen exposure. We found that Xpa-Null Hupki mice and HUFs were more sensitive to 3-NBA treatment than their wild-type (Xpa-WT) counterparts. However, following 3-NBA treatment and immortalisation, a similar frequency of TP53-mutant clones arose from Xpa-WT and Xpa-Null HUF cultures. In cells from both Xpa genotypes G:CT:A transversion was the predominant TP53 mutation type and mutations exhibited bias towards the non-transcribed strand. Thirty-two percent of 3-NBA-induced TP53 mutations occurred at CpG sites, all of which are hotspots for mutation in smokers' lung cancer (codons 157, 158, 175, 245, 248, 273, 282). We also examined 3-NBA-induced mutagenesis of an integrated lacZ reporter gene in HUFs, where we again observed a similar mutant frequency in Xpa-WT and Xpa-Null cells. Our findings suggest that 3-NBA-DNA adducts may evade removal by global genomic NER; the persistence of 3-NBA adducts in DNA may be an important factor in its mutagenicity. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

TP53 status and taxane-platinum versus platinum-based therapy in ovarian cancer patients: A non-randomized retrospective study

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Markowska Janina

2008-01-01

Full Text Available Abstract Background Taxane-platinum therapy (TP has replaced platinum-based therapy (PC or PAC, DNA damaging chemotherapy in the postoperative treatment of ovarian cancer patients; however, it is not always effective. TP53 protein plays a differential role in response to DNA-damaging agents and taxanes. We sought to define profiles of patients who benefit the most from TP and also of those who can be treated with PC. Methods We compared the effectiveness of PC/PAC (n = 253 and TP (n = 199 with respect to tumor TP53 accumulation in ovarian cancer patients with FIGO stage IIB-IV disease; this was a non-randomized retrospective study. Immunohistochemical analysis was performed on 452 archival tumors; univariate and multivariate analysis by the Cox's and logistic regression models was performed in all patients and in subgroups with [TP53(+] and without TP53 accumulation [TP53(-]. Results The advantage of taxane-platinum therapy over platinum-based therapy was seen in the TP53(+, and not in the TP53(- group. In the TP53(+ group taxane-platinum therapy enhanced the probability of complete remission (p = .018, platinum sensitivity (p = .014, platinum highly sensitive response (p = .038 and longer survival (OS, p = .008. Poor tumor differentiation diminished the advantage from taxane-platinum therapy in the TP53(+ group. In the TP53(- group PC/PAC was at least equally efficient as taxane-platinum therapy and it enhanced the chance of platinum highly sensitive response (p = .010. However, in the TP53(- group taxane-platinum therapy possibly diminished the risk of death in patients over 53 yrs (p = .077. Among factors that positively interacted with taxane-platinum therapy in some analyses were endometrioid and clear cell type, FIGO III stage, bulky residual tumor, more advanced age of patient and moderate tumor differentiation. Conclusion Our results suggest that taxane-platinum therapy is particularly justified in patients with TP53(+ tumors or older

Low Prevalence of TP53 Mutations and MDM2 Amplifications in Pediatric Rhabdomyosarcoma

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Simona Ognjanovic

2012-01-01

Full Text Available The tumor suppressor gene TP53 is the most commonly mutated gene in human cancer. The reported prevalence of mutations in rhabdomyosarcoma (RMS varies widely, with recent larger studies suggesting that TP53 mutations in pediatric RMS may be extremely rare. Overexpression of MDM2 also attenuates p53 function. We have performed TP53 mutation/MDM2 amplification analyses in the largest series analyzed thus far, including DNA isolated from 37 alveolar and 38 embryonal RMS tumor samples obtained from the Cooperative Human Tissue Network (CHTN. Available samples were frozen tumor tissues (N=48 and histopathology slides. TP53 mutations in exons 4–9 were analyzed by direct sequencing in all samples, and MDM2 amplification analysis was performed by differential PCR on a subset of 22 samples. We found only one sample (1/75, 1.3% carrying a TP53 mutation at codon 259 (p.D259Y and no MDM2 amplification. Two SNPs in the TP53 pathway, associated with accelerated tumor onset in germline TP53 mutation carriers, (TP53 SNP72 (rs no. 1042522 and MDM2 SNP309 (rs no. 2279744, were not found to confer earlier tumor onset. In conclusion, we confirm the extremely low prevalence of TP53 mutations/MDM2 amplifications in pediatric RMS (1.33% and 0%, respectively. The possible inactivation of p53 function by other mechanisms thus remains to be elucidated.

Knockdown of HSPA9 induces TP53-dependent apoptosis in human hematopoietic progenitor cells.

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Tuoen Liu

Full Text Available Myelodysplastic syndromes (MDS are the most common adult myeloid blood cancers in the US. Patients have increased apoptosis in their bone marrow cells leading to low peripheral blood counts. The full complement of gene mutations that contribute to increased apoptosis in MDS remains unknown. Up to 25% of MDS patients harbor and acquired interstitial deletion on the long arm of chromosome 5 [del(5q], creating haploinsufficiency for a large set of genes including HSPA9. Knockdown of HSPA9 in primary human CD34+ hematopoietic progenitor cells significantly inhibits growth and increases apoptosis. We show here that HSPA9 knockdown is associated with increased TP53 expression and activity, resulting in increased expression of target genes BAX and p21. HSPA9 protein interacts with TP53 in CD34+ cells and knockdown of HSPA9 increases nuclear TP53 levels, providing a possible mechanism for regulation of TP53 by HSPA9 haploinsufficiency in hematopoietic cells. Concurrent knockdown of TP53 and HSPA9 rescued the increased apoptosis observed in CD34+ cells following knockdown of HSPA9. Reduction of HSPA9 below 50% results in severe inhibition of cell growth, suggesting that del(5q cells may be preferentially sensitive to further reductions of HSPA9 below 50%, thus providing a genetic vulnerability to del(5q cells. Treatment of bone marrow cells with MKT-077, an HSPA9 inhibitor, induced apoptosis in a higher percentage of cells from MDS patients with del(5q compared to non-del(5q MDS patients and normal donor cells. Collectively, these findings indicate that reduced levels of HSPA9 may contribute to TP53 activation and increased apoptosis observed in del(5q-associated MDS.

TP53 dysfunction in CLL: Implications for prognosis and treatment

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te Raa, Gera D.; Kater, Arnon P.

2016-01-01

Despite the availability of novel targeted agents, TP53 defects remain the most important adverse prognostic factor in chronic lymphocytic leukemia (CLL). Detection of deletion of TP53 locus (17p deletion) by fluorescent in situ hybridization (FISH) has become standard and performed prior to every

Germline TP53 mutations and single nucleotide polymorphisms in children Mutaciones y polimorfismos de un único nucleótido del gen TP53 en línea germinal en niños

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Pamela Valva

2009-02-01

Full Text Available Mutations in the gene TP53, which codifies the tumor suppressor protein p53, are found in about 50% of tumors. These mutations can occur not only at somatic level, but also in germline. Pediatric cancer patients, mostly with additional family history of malignancy, should be considered as potential TP53 germline mutation carriers. Germline TP53 mutations and polymorphisms have been widely studied to determine their relation with different tumors' pathogenesis. Our aim was to analyze the occurrence frequency of germline TP53 mutations and polymorphisms and to relate these to tumor development in a pediatric series. Peripheral blood mononuclear cell samples from 26 children with solid tumors [PST] and 21 pediatric healthy donors [HD] were analyzed for germline mutations and polymorphisms in TP53 gene spanning from exon 5 to 8 including introns 5 and 7. These PCR amplified fragments were sequenced to determine variations. A heterozygous mutation at codon 245 was found in 1/26 PST and 0/21 HD. Comparative polymorphisms distribution, at position 14181 and 14201(intron 7, between HD and PST revealed a trend of association (p= 0.07 with cancer risk. HD group disclosed a similar polymorphism distribution as published data for Caucasian and Central/South American populations. This is the first study about TP53 variant frequency and distribution in healthy individuals and cancer patients in Argentina.El gen que codifica para la proteína supresora de tumor p53 (TP53 se encuentra mutado en aproximadamente el 50% de los tumores. Estas mutaciones pueden presentarse como somáticas o en línea germinal. Los niños con tumores, sobre todo aquellos con historia familiar de enfermedad oncológica, deben considerarse potenciales portadores de mutaciones en línea germinal. Las mutaciones de TP53 y los polimorfismos son estudiados para determinar su relación con la patogénesis de diferentes tumores. El objetivo del trabajo fue analizar la frecuencia de

Limited importance of the dominant-negative effect of TP53 missense mutations

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Stoczynska-Fidelus, Ewelina; Liberski, Pawel P; Rieske, Piotr; Szybka, Malgorzata; Piaskowski, Sylwester; Bienkowski, Michal; Hulas-Bigoszewska, Krystyna; Banaszczyk, Mateusz; Zawlik, Izabela; Jesionek-Kupnicka, Dorota; Kordek, Radzislaw

2011-01-01

Heterozygosity of TP53 missense mutations is related to the phenomenon of the dominant-negative effect (DNE). To estimate the importance of the DNE of TP53 mutations, we analysed the percentage of cancer cases showing a single heterozygous mutation of TP53 and searched for a cell line with a single heterozygous mutation of this gene. This approach was based on the knowledge that genes with evident DNE, such as EGFR and IDH1, represent nearly 100% of single heterozygous mutations in tumour specimens and cell lines. Genetic analyses (LOH and sequencing) performed for early and late passages of several cell lines originally described as showing single heterozygous TP53 mutations (H-318, G-16, PF-382, MOLT-13, ST-486 and LS-123). Statistical analysis of IARC TP53 and SANGER databases. Genetic analyses of N-RAS, FBXW7, PTEN and STR markers to test cross-contamination and cell line identity. Cell cloning, fluorescence-activated cell sorting and SSCP performed for the PF-382 cell line. A database study revealed TP53 single heterozygous mutations in 35% of in vivo (surgical and biopsy) samples and only 10% of cultured cells (in vitro), although those numbers appeared to be overestimated. We deem that published in vivo TP53 mutation analyses are not as rigorous as studies in vitro, and we did not find any cell line showing a stable, single heterozygous mutation. G16, PF-382 and MOLT-13 cells harboured single heterozygous mutations temporarily. ST-486, H-318 and LS-123 cell lines were misclassified. Specific mutations, such as R175H, R273H, R273L or R273P, which are reported in the literature to exert a DNE, showed the lowest percentage of single heterozygous mutations in vitro (about 5%). We suggest that the currently reported percentage of TP53 single heterozygous mutations in tumour samples and cancer cell lines is overestimated. Thus, the magnitude of the DNE of TP53 mutations is questionable. This scepticism is supported by database investigations showing that retention

SV40 large T-p53 complex: evidence for the presence of two immunologically distinct forms of p53

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Milner, J.; Gamble, J.

1985-01-01

The transforming protein of SV40 is the large T antigen. Large T binds a cellular protein, p53, which is potentially oncogenic by virtue of its functional involvement in the control of cell proliferation. This raises the possibility that p53 may mediate, in part, the transforming function of SV40 large T. Two immunologically distinct forms of p53 have been identified in normal cells: the forms are cell-cycle dependent, one being restricted to nondividing cells (p53-Go) and the second to dividing cells (p53-G divided by). The authors have now dissociated and probed the multimeric complex of SV40 large T-p53 for the presence of immunologically distinct forms of p53. Here they present evidence for the presence of p53-Go and p53-G divided by complexed with SV40 large T

Pediatric oncologist willingness to offer germline TP53 testing in osteosarcoma.

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Shaul, Eliana; Roth, Michael; Lo, Yungtai; Geller, David S; Hoang, Bang; Yang, Rui; Malkin, David; Gorlick, Richard; Gill, Jonathan

2018-03-15

Li-Fraumeni syndrome (LFS) is a cancer predisposition syndrome caused by mutations in the tumor-suppressor gene TP53. Osteosarcoma is a sentinel cancer in LFS. Prior studies using Sanger sequencing platforms have demonstrated that 3% of individuals with osteosarcoma harbor a mutation in TP53. New data from next-generation sequencing have demonstrated that 3.8% of patients with osteosarcoma have a known pathogenic variant, and an additional 5.7% carry exonic variants of unknown significance in TP53. Pediatric oncologists were e-mailed an anonymous 18-question survey assessing their willingness to offer TP53 germline testing to a child with osteosarcoma with or without a family history, and they were evaluated for changes in their choices with the prior data and the new data. One hundred seventy-seven pediatric oncologists (22%) responded to the survey. Respondents were more likely to offer TP53 testing to a patient with a positive family history (77.4% vs 12.4%; P offer TP53 testing once they were provided with the new data (25.4% vs 12.4%; P = .0038). The proportion of providers who responded that they were unsure increased significantly when they were presented with the new data (25.4% vs 10.2%; P = .0002). Potential implications for other family members and the possibility that surveillance imaging would detect new malignancies at an earlier stage were important factors influencing a provider's decision to offer TP53 testing. Recent data increase the proportion of providers willing to offer testing, and this suggests concern on the part of pediatric oncologists that variants of unknown significance may be disease-defining in rare cancers. Cancer 2018;124:1242-50. © 2018 American Cancer Society. © 2018 American Cancer Society.

Overexpression of RBBP6, alone or combined with mutant TP53, is predictive of poor prognosis in colon cancer.

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Jian Chen

Full Text Available Retinoblastoma binding protein 6 (RBBP6 plays an important role in chaperone-mediated ubiquitination and interacts with TP53 in carcinogenesis. However, the clinicopathologic significance of RBBP6 expression in colon cancer is unknown; in particular, the prognostic value of RBBP6 combined with TP53 expression has not been explored. Therefore, quantitative real-time PCR and western blot analyses were performed to detect RBBP6 expression in colon cancer tissues. RBBP6 and TP53 expression were assessed by immunohistochemistry in a tissue microarray format, in which the primary colon cancer tissue was paired with noncancerous tissue. Tissue specimens were obtained from 203 patients. We found that RBBP6 was overexpressed in colon tumorous tissues and was significantly associated with clinical stage, depth of tumor invasion, lymph node metastasis (LNM, distant metastasis, and histologic grade. Further studies revealed that a corresponding correlation between RBBP6 overexpression and mutant TP53 was evident in colon cancer (r = 0.450; P<0.001. RBBP6 expression was an independent prognostic factor for overall survival (OS and disease free survival (DFS. Interestingly, patients with tumors that had both RBBP6 overexpression and mutant TP53 protein accumulation relapsed and died within a significantly short period after surgery (P<0.001. Multivariate analysis showed that patients with LNM and patients with both RBBP6- and TP53-positive tumors had extremely poor OS (HR 6.75; 95% CI 2.63-17.35; P<0.001 and DFS (HR 8.08; 95% CI 2.80-23.30; P<0.001. These clinical findings indicate that the assessment of both RBBP6 and mutant TP53 expression will be helpful in predicting colon cancer prognosis.

Single nucleotide polymorphisms in the TP53 region and susceptibility to invasive epithelial ovarian cancer

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Schildkraut, Joellen M; Goode, Ellen L; Clyde, Merlise A

2009-01-01

The p53 protein is critical for multiple cellular functions including cell growth and DNA repair. We assessed whether polymorphisms in the region encoding TP53 were associated with risk of invasive ovarian cancer. The study population includes a total of 5,206 invasive ovarian cancer cases (2,829...

Polimorfismo do gene tp53 no códon 72 em pacientes com suspeita de LMC Codon 72 polymorphism of the TP53 gene in patients suspected to have CML

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Camila S. Hamú

2007-12-01

Full Text Available A leucemia mielóide crônica (LMC é uma doença proliferativa do sistema hematopoiético, caracterizada pela expansão clonal de uma célula-tronco primitiva e pluripotente denominada stem cell. Este tipo de leucemia está associado, em 90% dos casos, à translocação t(9;22(q34;q11. Essa alteração cromossômica estrutural codifica para uma proteína quimérica BCR-ABL, que confere às células leucêmicas uma alta resistência à morte, independente do agente indutor desse processo. A proteína p53 é uma reguladora transcricional induzida por danos no DNA, fato que resulta na parada do ciclo celular com conseqüente ativação de mecanismos de reparo ou mesmo na indução à apoptose. As mutações no gene TP53 são as alterações genéticas mais comuns em tumores malignos humanos. O presente estudo teve como objetivo genotipar e determinar a freqüência alélica do polimorfismo do TP53 no códon 72 (arginina - Arg e prolina - Pro, em pacientes com suspeita de LMC, pela Reação em Cadeia da Polimerase. Desta forma, os resultados indicaram que 73,4% (23/30 dos pacientes apresentaram homozigose para arginina (Arg/Arg e 26,6% (7/30 heterozigose (Arg/Pro. Não foi encontrado nenhum paciente homozigoto para prolina (Pro/Pro. Os resultados obtidos sugerem que o polimorfismo do gene TP53 no códon 72 não é um fator de risco importante para a iniciação, promoção e progressão da LMC.Chronic myeloid leukemia (CML is a proliferative disorder of the hematopoietic system characterized by clonal expansion of a primitive and pluripotent stem cell. In this type of leukemia, up to 90% of all cases is associated to a specific chromosomal translocation, t(9;22(q34;q11. The genomic alteration results in a chimeric protein, BCR-ABL, that confers a high resistance leukemia cells to death, independent of the induction mechanism of this process. Protein p53 is a transcriptional factor expressed after DNA damage which ceases cell cycle progression and

Prognostic value of TP53 transcriptional activity on p21 and bax in patients with esophageal squamous cell carcinomas treated by definitive chemoradiotherapy

International Nuclear Information System (INIS)

Michel, Pierre; Magois, Karine; Robert, Valerie; Chiron, Anne; Lepessot, Florence; Bodenant, Corinne; Roque, Isabelle; Seng, Sok H.; Frebourg, Thierry; Paillot, Bernard

2002-01-01

Purpose: The aim of this study was to evaluate biologic factors on survival and clinical response after definitive concomitant chemoradiotherapy (CRT) in patients with esophageal squamous cell carcinoma (ESCC). Methods and Materials: TP53 protein hyperexpression (immunochemistry [IHC]) and functional assay (FA) of TP53, measuring the ability of TP53 to transactivate p21 and bax reporter systems, were performed in patients with ESCC treated by CRT. The impact of parameters studied on survival and clinical response to CRT was assessed. Results: Thirty-eight patients with ESCC were included. TP53 alterations were detected in 84.2% of cases with FA. All TP53 mutations abolished the transactivation of p21 and bax reporter systems. After CRT, complete response rate was 55.3%. The median survival of the population was 17.5 months. Serum albumin (p=0.002), weight loss <10% (p=0.005), and response to treatment (p<0.001) were significantly linked with survival. TP53 alteration in FA was not significantly predictive of response to CRT (p=0.132) nor survival (p=0.154). Conclusions: Our results suggest that wild-type TP53 in ESCC could be associated with good response to definitive CRT. However, the small rate of ESCC with wild-type TP53 suggests that systematic determination of TP53 status is not appropriate for the management of the ESCC population

High resolution melting for mutation scanning of TP53 exons 5–8

International Nuclear Information System (INIS)

Krypuy, Michael; Dobrovic, Alexander; Ahmed, Ahmed Ashour; Etemadmoghadam, Dariush; Hyland, Sarah J; Australian Ovarian Cancer Study Group; Fazio, Anna de; Fox, Stephen B; Brenton, James D; Bowtell, David D

2007-01-01

p53 is commonly inactivated by mutations in the DNA-binding domain in a wide range of cancers. As mutant p53 often influences response to therapy, effective and rapid methods to scan for mutations in TP53 are likely to be of clinical value. We therefore evaluated the use of high resolution melting (HRM) as a rapid mutation scanning tool for TP53 in tumour samples. We designed PCR amplicons for HRM mutation scanning of TP53 exons 5 to 8 and tested them with DNA from cell lines hemizygous or homozygous for known mutations. We assessed the sensitivity of each PCR amplicon using dilutions of cell line DNA in normal wild-type DNA. We then performed a blinded assessment on ovarian tumour DNA samples that had been previously sequenced for mutations in TP53 to assess the sensitivity and positive predictive value of the HRM technique. We also performed HRM analysis on breast tumour DNA samples with unknown TP53 mutation status. One cell line mutation was not readily observed when exon 5 was amplified. As exon 5 contained multiple melting domains, we divided the exon into two amplicons for further screening. Sequence changes were also introduced into some of the primers to improve the melting characteristics of the amplicon. Aberrant HRM curves indicative of TP53 mutations were observed for each of the samples in the ovarian tumour DNA panel. Comparison of the HRM results with the sequencing results revealed that each mutation was detected by HRM in the correct exon. For the breast tumour panel, we detected seven aberrant melt profiles by HRM and subsequent sequencing confirmed the presence of these and no other mutations in the predicted exons. HRM is an effective technique for simple and rapid scanning of TP53 mutations that can markedly reduce the amount of sequencing required in mutational studies of TP53

TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth.

Science.gov (United States)

Haricharan, Svasti; Brown, Powel

2015-06-23

Breast cancer is a leading cause of cancer-related death, and it is important to understand pathways that drive the disease to devise effective therapeutic strategies. Our results show that Toll-like receptor 4 (TLR4) drives breast cancer cell growth differentially based on the presence of TP53, a tumor suppressor. TP53 is mutationally inactivated in most types of cancer and is mutated in 30-50% of diagnosed breast tumors. We demonstrate that TLR4 activation inhibits growth of TP53 wild-type cells, but promotes growth of TP53 mutant breast cancer cells by regulating proliferation. This differential effect is mediated by changes in tumor cell cytokine secretion. Whereas TLR4 activation in TP53 mutant breast cancer cells increases secretion of progrowth cytokines, TLR4 activation in TP53 wild-type breast cancer cells increases type I IFN (IFN-γ) secretion, which is both necessary and sufficient for mediating TLR4-induced growth inhibition. This study identifies a novel dichotomous role for TLR4 as a growth regulator and a modulator of tumor microenvironment in breast tumors. These results have translational relevance, demonstrating that TP53 mutant breast tumor growth can be suppressed by pharmacologic TLR4 inhibition, whereas TLR4 inhibitors may in fact promote growth of TP53 wild-type tumors. Furthermore, using data generated by The Cancer Genome Atlas consortium, we demonstrate that the effect of TP53 mutational status on TLR4 activity may extend to ovarian, colon, and lung cancers, among others, suggesting that the viability of TLR4 as a therapeutic target depends on TP53 status in many different tumor types.

Association of mRNA expression of TP53 and the TP53 codon 72 Arg/Pro gene polymorphism with colorectal cancer risk in Asian population: a bioinformatics analysis and meta-analysis.

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Dong, Zhiyong; Zheng, Longzhi; Liu, Weimin; Wang, Cunchuan

2018-01-01

The relationship between TP53 codon 72 Pro/Arg gene polymorphism and colorectal cancer risk in Asians is still controversial, and this bioinformatics analysis and meta-analysis was performed to assess the associations. The association studies were identified from PubMed, and eligible reports were included. RevMan 5.3.1 software, Oncolnc, cBioPortal, and Oncomine online tools were used for statistical analysis. A random/fixed effects model was used in meta-analysis. The data were reported as risk ratios or mean differences with corresponding 95% CI. We confirmed that TP53 was associated with colorectal cancer, the alteration frequency of TP53 was 53% mutation and 7% deep deletion, and TP53 mRNA expression was different in different types of colorectal cancer based on The Cancer Genome Atlas database. Then, 18 studies were included that examine the association of TP53 codon 72 gene polymorphism with colorectal cancer risk in Asians. The meta-analysis indicated that TP53 Pro allele and Pro/Pro genotype were associated with colorectal cancer risk in Asian population, but Arg/Arg genotype was not (Pro allele: odds ratios [OR]=1.20, 95% CI: 1.06 to 1.35, P =0.003; Pro/Pro genotype: OR=1.39, 95% CI: 1.15 to 1.69, P =0.0007; Arg/Arg genotype: OR=0.86, 95% CI: 0.74 to 1.00, P =0.05). Interestingly, in the meta-analysis of the controls from the population-based studies, we found that TP53 codon 72 Pro/Arg gene polymorphism was associated with colorectal cancer risk (Pro allele: OR=1.33, 95% CI: 1.15 to 1.55, P =0.0002; Pro/Pro genotype: OR=1.61, 95% CI: 1.28 to 2.02, P colorectal cancer, but the different value levels of mRNA expression were not associated with survival rate of colon and rectal cancer. TP53 Pro allele and Pro/Pro genotype were associated with colorectal cancer risk in Asians.

CNPY2 promoted the proliferation of renal cell carcinoma cells and increased the expression of TP53

International Nuclear Information System (INIS)

Taniguchi, Hidefumi; Ito, Saya; Ueda, Takashi; Morioka, Yukako; Kayukawa, Naruhiro; Ueno, Akihisa; Nakagawa, Hideo; Fujihara, Atsuko; Ushijima, So; Kanazawa, Motohiro; Hongo, Fumiya; Ukimura, Osamu

2017-01-01

Renal cell carcinoma (RCC) is the most common type of kidney cancer. However, the mechanisms underlying the progression of the disease are not well understood. The data in this report suggest that canopy FGF signaling regulator 2 (CNPY2) is a promoter of RCC progression. We found that CNPY2 significantly promoted growth of RCC cells and upregulated TP53 gene expression. Although TP53 is widely known as a tumor suppressor, in RCC TP53 promoted tumor cell growth. A typical p53 target gene, CDKN1A, was upregulated by both p53 and CNPY2 in RCC cells, suggesting that CNPY2 increased the expression level of TP53. Consistent with these results, CNPY2 and TP53 expression levels were positively correlated in RCC patients. These findings suggested that CNPY2 promoted cancer cell growth in RCC through regulating TP53 gene expression. - Highlights: • CNPY2 promoted growth of renal cell carcinoma (RCC) cells. • TP53 expression levels were increased by CNPY2 in RCC cells. • Growth of RCC cells was promoted by TP53. • CNPY2 expression positively correlated with TP53 expression in RCC patients.

Mutations in TP53 tumor suppressor gene in wood dust-related sinonasal cancer

DEFF Research Database (Denmark)

Holmila, Reetta; Bornholdt, Jette; Heikkilä, Pirjo

2010-01-01

The causal role of work-related exposure to wood dust in the development of sinonasal cancer has long been established by numerous epidemiologic studies. To study molecular changes in these tumors, we analyzed TP53 gene mutations in 358 sinonasal cancer cases with or without occupational exposure...... affected the ORs only slightly. Smoking did not influence the occurrence of TP53 mutation; however, it was associated with multiple mutations (p = 0.03). As far as we are aware, this is the first study to demonstrate a high prevalence of TP53 mutation-positive cases in a large collection of sinonasal...... cancers with data on occupational exposure. Our results indicate that mutational mechanisms, in particular TP53 mutations, are associated with work-related exposure to wood dust in sinonasal cancer....

TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth

OpenAIRE

Haricharan, Svasti; Brown, Powel

2015-01-01

This study fundamentally alters our understanding of how TLR4 drives breast cancer. Although TLR4 was previously considered a tumor promoter, we demonstrate a complex, TP53-dependent role for TLR4 in regulating tumor growth. TP53 is a tumor suppressor commonly inactivated across cancer types. In TP53 wild-type cancer cells, TLR4 activation causes secretion of IFN-γ into the microenvironment, resulting in induction of p21 and inhibition of cell growth. Conversely, TLR4 activation in TP53 mutan...

Bilateral wilms tumor with TP53-related anaplasia.

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Popov, Sergey D; Vujanic, Gordan M; Sebire, Neil J; Chagtai, Tasnim; Williams, Richard; Vaidya, Sucheta; Pritchard-Jones, Kathy

2013-01-01

Wilms tumor (WT) with diffuse anaplasia has an unfavorable prognosis and is often (>70%) associated with mutations in the TP53 gene. Although most WTs are unilateral, 5-10% are bilateral, and they are almost always present with nephrogenic rests. The latter are considered a precursor of WT. Two cases of bilateral WTs with nephroblastomatosis, in which anaplastic changes were detected over a period of time, were analyzed using clinical, radiological, histopathological, and molecular-genetic data. TP53 was analyzed by direct sequencing of its full coding sequence and intron-exon boundaries in 11 fragments. DNA was extracted from paraffin-embedded or frozen specimens. High-resolution genomic copy number profiling was carried out by UCL Genomics on the Affymetrix Human Mapping 250K Nsp or Genome-Wide Human SNP Array 6.0 platform. Both cases demonstrated a strong association between the appearance of anaplastic clones and TP53 mutations. Synchronous ganglioneuroma was diagnosed in one case. Our cases are unique as they represent a long disease history and demonstrate the difficulties in managing rare cases of bilateral WT with anaplasia. These cases also emphasize the practical importance of modern molecular-genetic techniques and their clinical application. Moreover, they highlight the issue of the adequate sampling needed in order to gather comprehensive, efficient, and sufficient information about genetic events in a single tumor.

The prognostic values of the expression of Vimentin, TP53, and Podoplanin in patients with cervical cancer.

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Lin, Jiaying; Lu, Jiaqi; Wang, Chao; Xue, Xiaohong

2017-01-01

Epithelial-mesenchymal transition (EMT), TP53, and Podoplanin have been implicated in the tumorigenesis and metastasis of human cancers. Nevertheless, the clinical significance of these markers in cancer patients is still not clear. In this study, we sought to determine the prognostic values of Vimentin, TP53, and Podoplanin in patients with cervical cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis were performed to determine the messenger RNA and protein expression levels of Vimentin, TP53, and Podoplanin, respectively, in cervical squamous cell carcinoma and adjacent normal cervical tissues. Additionally, the expression levels of Podoplanin were also measured in 130 cervical cancer patients (FIGO stages Ib1-IIa2) using immunohistochemistry (IHC) staining. The mRNA expression levels of Vimentin, TP53, and Podoplanin were considerably elevated in cervical cancer tissues, compared with those in the adjacent normal cervical tissues. Additionally, the protein expression levels of Vimentin were closely correlated with the age of onset (P = 0.007), lymph node metastasis (P = 0.007), lymphatic invasion (P = 0.024), disease recurrence (P < 0.001), and the clinical prognosis of patients with cervical cancer (P < 0.001). Our multivariate analysis also suggests that Vimentin is an independent marker for survival in cervical cancer patients. Furthermore, the expression levels of Vimentin are negatively correlated with the proliferation marker Ki67 expression. Our data show that Vimentin can serve as an independent prognostic marker for cervical cancer patients with primary surgery. Registration number ChiCTR-TRC-06000236 Registered 15 December 2006.

Genetic variation in the TP53 pathway and bladder cancer risk. a comprehensive analysis.

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Silvia Pineda

Full Text Available Germline variants in TP63 have been consistently associated with several tumors, including bladder cancer, indicating the importance of TP53 pathway in cancer genetic susceptibility. However, variants in other related genes, including TP53 rs1042522 (Arg72Pro, still present controversial results. We carried out an in depth assessment of associations between common germline variants in the TP53 pathway and bladder cancer risk.We investigated 184 tagSNPs from 18 genes in 1,058 cases and 1,138 controls from the Spanish Bladder Cancer/EPICURO Study. Cases were newly-diagnosed bladder cancer patients during 1998-2001. Hospital controls were age-gender, and area matched to cases. SNPs were genotyped in blood DNA using Illumina Golden Gate and TaqMan assays. Cases were subphenotyped according to stage/grade and tumor p53 expression. We applied classical tests to assess individual SNP associations and the Least Absolute Shrinkage and Selection Operator (LASSO-penalized logistic regression analysis to assess multiple SNPs simultaneously.Based on classical analyses, SNPs in BAK1 (1, IGF1R (5, P53AIP1 (1, PMAIP1 (2, SERINPB5 (3, TP63 (3, and TP73 (1 showed significant associations at p-value≤0.05. However, no evidence of association, either with overall risk or with specific disease subtypes, was observed after correction for multiple testing (p-value≥0.8. LASSO selected the SNP rs6567355 in SERPINB5 with 83% of reproducibility. This SNP provided an OR = 1.21, 95%CI 1.05-1.38, p-value = 0.006, and a corrected p-value = 0.5 when controlling for over-estimation.We found no strong evidence that common variants in the TP53 pathway are associated with bladder cancer susceptibility. Our study suggests that it is unlikely that TP53 Arg72Pro is implicated in the UCB in white Europeans. SERPINB5 and TP63 variation deserve further exploration in extended studies.

TP53 codon 72 polymorphism in pigmentary phenotypes

Indian Academy of Sciences (India)

2012-01-20

Jan 20, 2012 ... pigmentation by acting as a transcription factor for other genes that are ... skin phototype I-II, burns after exposure to UVR and the development of .... morphisms of TP53 codon 72 with breast carcinoma risk: evidence from ...

Predictive and prognostic impact of TP53 mutations and MDM2 promoter genotype in primary breast cancer patients treated with epirubicin or paclitaxel.

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Ranjan Chrisanthar

Full Text Available BACKGROUND: TP53 mutations have been associated with resistance to anthracyclines but not to taxanes in breast cancer patients. The MDM2 promoter single nucleotide polymorphism (SNP T309G increases MDM2 activity and may reduce wild-type p53 protein activity. Here, we explored the predictive and prognostic value of TP53 and CHEK2 mutation status together with MDM2 SNP309 genotype in stage III breast cancer patients receiving paclitaxel or epirubicin monotherapy. EXPERIMENTAL DESIGN: Each patient was randomly assigned to treatment with epirubicin 90 mg/m(2 (n = 109 or paclitaxel 200 mg/m(2 (n = 114 every 3rd week as monotherapy for 4-6 cycles. Patients obtaining a suboptimal response on first-line treatment requiring further chemotherapy received the opposite regimen. Time from last patient inclusion to follow-up censoring was 69 months. Each patient had snap-frozen tumor tissue specimens collected prior to commencing chemotherapy. PRINCIPAL FINDINGS: While TP53 and CHEK2 mutations predicted resistance to epirubicin, MDM2 status did not. Neither TP53/CHEK2 mutations nor MDM2 status was associated with paclitaxel response. Remarkably, TP53 mutations (p = 0.007 but also MDM2 309TG/GG genotype status (p = 0.012 were associated with a poor disease-specific survival among patients having paclitaxel but not patients having epirubicin first-line. The effect of MDM2 status was observed among individuals harbouring wild-type TP53 (p = 0.039 but not among individuals with TP53 mutated tumors (p>0.5. CONCLUSION: TP53 and CHEK2 mutations were associated with lack of response to epirubicin monotherapy. In contrast, TP53 mutations and MDM2 309G allele status conferred poor disease-specific survival among patients treated with primary paclitaxel but not epirubicin monotherapy.

Analysis of full coding sequence of the TP53 gene in invasive vulvar cancers: Implications for therapy.

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Kashofer, Karl; Regauer, Sigrid

2017-08-01

This study evaluates the frequency and type of TP53 gene mutations and HPV status in 72 consecutively diagnosed primary invasive vulvar squamous cell carcinomas (SCC) during the past 5years. DNA of formalin-fixed and paraffin embedded tumour tissue was analysed for 32 HPV subtypes and the full coding sequence of the TP53 gene, and correlated with results of p53 immunohistochemistry. 13/72 (18%) cancers were HPV-induced squamous cell carcinomas, of which 1/13 (8%) carcinoma harboured a somatic TP53 mutation. Among the 59/72 (82%) HPV-negative cancers, 59/72 (82%) SCC were HPV-negative with wild-type gene in 14/59 (24%) SCC and somatic TP53 mutations in 45/59 (76%) SCC. 28/45 (62%) SCC carried one (n=20) or two (n=8) missense mutations. 11/45 (24%) carcinomas showed a single disruptive mutation (3× frame shift, 7× stop codon, 1× deletion), 3/45 SCC a splice site mutation. 3/45 (7%) carcinomas had 2 or 3 different mutations. 18 different "hot spot" mutations were observed in 22/45 cancers (49%; 5× R273, 3× R282; 2× each Y220, R278, R248). Immunohistochemical p53 over expression was identified in most SCC with missense mutations, but not in SCC with disruptive TP53 mutations or TP53 wild-type. 14/45 (31%) patients with TP53 mutated SCC died of disease within 12months (range 2-24months) versus 0/13 patients with HPV-induced carcinomas and 0/14 patients with HPV-negative, TP53 wild-type carcinomas. 80% of primary invasive vulvar SCC were HPV-negative carcinomas with a high frequency of disruptive mutations and "hot spot" TP53 gene mutations, which have been linked to chemo- and radioresistance. The death rate of patients with p53 mutated vulvar cancers was 31%. Immunohistochemical p53 over expression could not reliably identify SCC with TP53 gene mutation. Pharmacological therapies targeting mutant p53 will be promising strategies for personalized therapy in patients with TP53 mutated vulvar cancers. Copyright © 2017. Published by Elsevier Inc.

RITA (Reactivating p53 and Inducing Tumor Apoptosis) is efficient against TP53abnormal myeloma cells independently of the p53 pathway.

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Surget, Sylvanie; Descamps, Géraldine; Brosseau, Carole; Normant, Vincent; Maïga, Sophie; Gomez-Bougie, Patricia; Gouy-Colin, Nadège; Godon, Catherine; Béné, Marie C; Moreau, Philippe; Le Gouill, Steven; Amiot, Martine; Pellat-Deceunynck, Catherine

2014-06-14

The aim of this study was to evaluate the efficacy of the p53-reactivating drugs RITA and nutlin3a in killing myeloma cells. A large cohort of myeloma cell lines (n = 32) and primary cells (n = 21) was used for this study. This cohort contained cell lines with various TP53 statuses and primary cells with various incidences of deletion of chromosome 17. Apoptosis was evaluated using flow cytometry with Apo2.7 staining of the cell lines or via the loss of the myeloma-specific marker CD138 in primary cells. Apoptosis was further confirmed by the appearance of a subG1 peak and the activation of caspases 3 and 9. Activation of the p53 pathway was monitored using immunoblotting via the expression of the p53 target genes p21, Noxa, Bax and DR5. The involvement of p53 was further studied in 4 different p53-silenced cell lines. Both drugs induced the apoptosis of myeloma cells. The apoptosis that was induced by RITA was not related to the TP53 status of the cell lines or the del17p status of the primary samples (p = 0.52 and p = 0.80, respectively), and RITA did not commonly increase the expression level of p53 or p53 targets (Noxa, p21, Bax or DR5) in sensitive cells. Moreover, silencing of p53 in two TP53(mutated) cell lines failed to inhibit apoptosis that was induced by RITA, which confirmed that RITA-induced apoptosis in myeloma cells was p53 independent. In contrast, apoptosis induced by nutlin3a was directly linked to the TP53 status of the cell lines and primary samples (p RITA, in contrast to nutlin3a, effectively induced apoptosis in a subset of MM cells independently of p53. The findings and could be of interest for patients with a 17p deletion, who are resistant to current therapies.

Oropharyngeal Squamous Cell Carcinoma Treated With Radiotherapy or Radiochemotherapy: Prognostic Role of TP53 and HPV Status

International Nuclear Information System (INIS)

Fallai, Carlo; Perrone, Federica; Licitra, Lisa; Pilotti, Silvana; Locati, Laura; Bossi, Paolo; Orlandi, Ester; Palazzi, Mauro; Olmi, Patrizia

2009-01-01

Purpose: To study the prognostic value of the TP53 mutation and human papilloma virus (HPV) status in oropharyngeal squamous cell carcinoma (OPSCC). Methods and materials: The TP53 mutation and HPV status were analyzed in 78 cases of locoregionally advanced OPSCC. The possible correlation of these factors with locoregiownal control, relapse-free survival, disease-specific survival, and overall survival (OS) was also investigated. Results: Of these 78 cases, 22 had disruptive and 22 had non-disruptive (silent) TP53 mutations; the remaining 34 cases had wild-type (WT) TP53. HPV 16 DNA was found in 9 cases (11%), but all HPV-positive (HPV+) cases carried a functional p53 protein, except for 1 case that had a silent mutation. HPV+ patients fared better than HPV-negative (HPV-) patients in terms of all survival parameters, with highly statistically significant differences between the groups. Specifically, no distant metastases were observed in the HPV+ patients, whereas they occurred in 17% of the HPV- patients. However, no difference was observed between the WT TP53 and mutation group, even when this was analyzed in terms of disruptive and non-disruptive mutations. Regardless, treatment with chemotherapy nearly doubled the 5-year OS rates, both in the mutation (42% vs. 22%) and WT (30 vs. 16%) group, but only the mutation group showed improvement in all survival parameters. In addition, the second tumor-free 5-year survival rate was 72% in HPV- cases, but no second tumors were observed in HPV+ and WT p53 cases. Conclusions: Patients with HPV+ OPSCC have an excellent prognosis after radiochemotherapy, but cisplatin-based chemotherapy may not confer a satisfactory outcome, especially in WT cases, thereby justifying the additional or alternative use of taxanes and epidermal growth factor receptors inhibitors. Uncommon distant metastases and second tumors in the HPV+ group may be cause for clinicians to review the follow-up policies in these patients.

IDH1/IDH2 but Not TP53 Mutations Predict Prognosis in Bulgarian Glioblastoma Patients

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Gergana Stancheva

2014-01-01

Full Text Available Mutations in genes encoding isocitrate dehydrogenase isoforms 1 (IDH1 and 2 (IDH2 have been associated with good prognosis for patients with brain neoplasias and have been commonly found together with mutated TP53 gene. To determine the prevalence of IDH1, IDH2, and TP53 mutations and their impact on overall survival 106 glioblastoma patients were analysed. IDH1 mutations were detected in 13 and IDH2 mutation in one patient. Two homozygous samples with R132H mutation in IDH1 gene and a novel aberration K129R in IDH2 gene were found. Sixty-four percent of IDH1/IDH2 mutated tumours harboured also a mutation in TP53 gene. Genetic aberrations in TP53 were present in 37 patients. Statistical analysis of the impact of the studied factors on the overall survival showed that the mutations in IDH1/IDH2, but not the ones in TP53, were associated with longer survival. Also, the impact of age on prognosis was confirmed. This is the first comprehensive study on glioblastomas in Bulgaria. Our results suggest that IDH1/IDH2 but not TP53 mutations together with other prognostic factors such as age might be applied in clinical practice for prediction of outcome in patients with glioblastomas.

TP53 mutational status is a potential marker for risk stratification in Wilms tumour with diffuse anaplasia.

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Mariana Maschietto

Full Text Available The presence of diffuse anaplasia in Wilms tumours (DAWT is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information.We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n = 32 and gene expression (n = 36 arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling.From the 40 cases, 22 (55% had TP53 mutations (2 detected only after deep-sequencing, 20 of which also had 17p loss (91%; 18 (45% cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n = 25 had an increased risk of recurrence as a first event (p = 0.03, hazard ratio (HR, 3.89; 95% confidence interval (CI, 1.26-16.0 and death (p = 0.04, HR, 4.95; 95% CI, 1.36-31.7 compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p = 0.03. These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes.This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker.

TP53 mutational status is a potential marker for risk stratification in Wilms tumour with diffuse anaplasia.

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Maschietto, Mariana; Williams, Richard D; Chagtai, Tasnim; Popov, Sergey D; Sebire, Neil J; Vujanic, Gordan; Perlman, Elizabeth; Anderson, James R; Grundy, Paul; Dome, Jeffrey S; Pritchard-Jones, Kathy

2014-01-01

The presence of diffuse anaplasia in Wilms tumours (DAWT) is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information. We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n = 32) and gene expression (n = 36) arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling. From the 40 cases, 22 (55%) had TP53 mutations (2 detected only after deep-sequencing), 20 of which also had 17p loss (91%); 18 (45%) cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n = 25) had an increased risk of recurrence as a first event (p = 0.03, hazard ratio (HR), 3.89; 95% confidence interval (CI), 1.26-16.0) and death (p = 0.04, HR, 4.95; 95% CI, 1.36-31.7) compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p = 0.03). These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes. This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker.

Molecular Alterations of TP53 are a Defining Feature of Ovarian High-Grade Serous Carcinoma: A Rereview of Cases Lacking TP53 Mutations in The Cancer Genome Atlas Ovarian Study.

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Vang, Russell; Levine, Douglas A; Soslow, Robert A; Zaloudek, Charles; Shih, Ie-Ming; Kurman, Robert J

2016-01-01

The Cancer Genome Atlas has reported that 96% of ovarian high-grade serous carcinomas (HGSCs) have TP53 somatic mutations suggesting that mutation of this gene is a defining feature of this neoplasm. In the current study, 5 gynecologic pathologists independently evaluated hematoxylin and eosin slides of 14 available cases from The Cancer Genome Atlas classified as HGSC that lacked a TP53 mutation. The histologic diagnoses rendered by these pathologists and the accompanying molecular genetic data are the subject of this report. Only 1 case (Case 5), which contained a homozygous deletion of TP53, had unanimous interobserver agreement for a diagnosis of pure HGSC. In 1 case (Case 3), all 5 observers (100%) rendered a diagnosis of HGSC; however, 3 observers (60%) noted that the histologic features were not classic for HGSC and suggested this case may have arisen from a low-grade serous carcinoma (arisen from an alternate pathway compared with the usual HGSC). In 2 cases (Cases 4 and 12), only 3 observers (60%) in each case, respectively, interpreted it as having a component of HGSC. In the remaining 10 (71%) of tumors (Cases 1, 2, 6-11, 13, and 14), the consensus diagnosis was not HGSC, with individual diagnoses including low-grade serous carcinoma, high-grade endometrioid carcinoma, HGSC, metastatic carcinoma, clear cell carcinoma, atypical proliferative (borderline) serous tumor, and adenocarcinoma, not otherwise specified. Therefore, 13 (93%) of the tumors (Cases 1-4 and 6-14) were either not a pure HGSC or represented a diagnosis other than HGSC, all with molecular results not characteristic of HGSC. Accordingly, our review of the TP53 wild-type HGSCs reported in The Cancer Genome Atlas suggests that 100% of de novo HGSCs contain TP53 somatic mutations or deletions, with the exception of the rare HGSCs that develop from a low-grade serous tumor precursor. We, therefore, propose that lack of molecular alterations of TP53 are essentially inconsistent with the

Ibrutinib for previously untreated and relapsed or refractory chronic lymphocytic leukaemia with TP53 aberrations

DEFF Research Database (Denmark)

Farooqui, Mohammed Z H; Valdez, Janet; Martyr, Sabrina

2015-01-01

BACKGROUND: Patients with chronic lymphocytic leukaemia (CLL) with TP53 aberrations respond poorly to first-line chemoimmunotherapy, resulting in early relapse and short survival. We investigated the safety and activity of ibrutinib in previously untreated and relapsed or refractory CLL with TP53...... aberrations. METHODS: In this investigator-initiated, single-arm phase 2 study, we enrolled eligible adult patients with active CLL with TP53 aberrations at the National Institutes of Health Clinical Center (Bethesda, MD, USA). Patients received 28-day cycles of ibrutinib 420 mg orally once daily until...... in one (2%) patient. INTERPRETATION: The activity and safety profile of single-agent ibrutinib in CLL with TP53 aberrations is encouraging and supports its consideration as a novel treatment option for patients with this high-risk disease in both first-line and second-line settings. FUNDING: Intramural...

Fischer-344 Tp53-knockout rats exhibit a high rate of bone and brain neoplasia with frequent metastasis

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Sarah A. Hansen

2016-10-01

Full Text Available Somatic mutations in the Tp53 tumor suppressor gene are the most commonly seen genetic alterations in cancer, and germline mutations in Tp53 predispose individuals to a variety of early-onset cancers. Development of appropriate translational animal models that carry mutations in Tp53 and recapitulate human disease are important for drug discovery, biomarker development and disease modeling. Current Tp53 mouse and rat models have significant phenotypic and genetic limitations, and often do not recapitulate certain aspects of human disease. We used a marker-assisted speed congenic approach to transfer a well-characterized Tp53-mutant allele from an outbred rat to the genetically inbred Fischer-344 (F344 rat to create the F344-Tp53tm1(EGFP-PacQly/Rrrc (F344-Tp53 strain. On the F344 genetic background, the tumor spectrum shifted, with the primary tumor types being osteosarcomas and meningeal sarcomas, compared to the hepatic hemangiosarcoma and lymphoma identified in the original outbred stock model. The Fischer model is more consistent with the early onset of bone and central nervous system sarcomas found in humans with germline Tp53 mutations. The frequency of osteosarcomas in F344-Tp53 homozygous and heterozygous animals was 57% and 36%, respectively. Tumors were highly representative of human disease radiographically and histologically, with tumors found primarily on long bones with frequent pulmonary metastases. Importantly, the rapid onset of osteosarcomas in this promising new model fills a current void in animal models that recapitulate human pediatric osteosarcomas and could facilitate studies to identify therapeutic targets.

Diffuse large B-cell lymphoma with combined TP53 mutation and MIR34A> methylation

DEFF Research Database (Denmark)

Asmar, Fazila; Hother, Christoffer; Kulosman, Gorjan

2014-01-01

and MIR34A methylation ("double hit") and these patients have an exceedingly poor prognosis with a median survival of 9.4 months (Phit") influence on survival. The TP53/MIR34A "double-hit" is an independent...... negative prognostic factor for survival (P=0.0002). In 2 DLBCL-cell lines with both TP53 mutation and promoter methylation of MIR34A, miR34A-5p is upregulated by 5-aza-2'deoxycytidine. Thus, the TP53/MIR34A "double hit" characterizes a very aggressive subgroup of DLBCL, which may be treatable...

Transcriptional dissection of melanoma identifies a high-risk subtype underlying TP53 family genes and epigenome deregulation

Science.gov (United States)

Badal, Brateil; Solovyov, Alexander; Di Cecilia, Serena; Chan, Joseph Minhow; Chang, Li-Wei; Iqbal, Ramiz; Aydin, Iraz T.; Rajan, Geena S.; Chen, Chen; Abbate, Franco; Arora, Kshitij S.; Tanne, Antoine; Gruber, Stephen B.; Johnson, Timothy M.; Fullen, Douglas R.; Phelps, Robert; Bhardwaj, Nina; Bernstein, Emily; Ting, David T.; Brunner, Georg; Schadt, Eric E.; Greenbaum, Benjamin D.; Celebi, Julide Tok

2017-01-01

BACKGROUND. Melanoma is a heterogeneous malignancy. We set out to identify the molecular underpinnings of high-risk melanomas, those that are likely to progress rapidly, metastasize, and result in poor outcomes. METHODS. We examined transcriptome changes from benign states to early-, intermediate-, and late-stage tumors using a set of 78 treatment-naive melanocytic tumors consisting of primary melanomas of the skin and benign melanocytic lesions. We utilized a next-generation sequencing platform that enabled a comprehensive analysis of protein-coding and -noncoding RNA transcripts. RESULTS. Gene expression changes unequivocally discriminated between benign and malignant states, and a dual epigenetic and immune signature emerged defining this transition. To our knowledge, we discovered previously unrecognized melanoma subtypes. A high-risk primary melanoma subset was distinguished by a 122-epigenetic gene signature (“epigenetic” cluster) and TP53 family gene deregulation (TP53, TP63, and TP73). This subtype associated with poor overall survival and showed enrichment of cell cycle genes. Noncoding repetitive element transcripts (LINEs, SINEs, and ERVs) that can result in immunostimulatory signals recapitulating a state of “viral mimicry” were significantly repressed. The high-risk subtype and its poor predictive characteristics were validated in several independent cohorts. Additionally, primary melanomas distinguished by specific immune signatures (“immune” clusters) were identified. CONCLUSION. The TP53 family of genes and genes regulating the epigenetic machinery demonstrate strong prognostic and biological relevance during progression of early disease. Gene expression profiling of protein-coding and -noncoding RNA transcripts may be a better predictor for disease course in melanoma. This study outlines the transcriptional interplay of the cancer cell’s epigenome with the immune milieu with potential for future therapeutic targeting. FUNDING

TP53 supports basal-like differentiation of mammary epithelial cells by preventing translocation of deltaNp63 into nucleoli

Science.gov (United States)

Munne, Pauliina M.; Gu, Yuexi; Tumiati, Manuela; Gao, Ping; Koopal, Sonja; Uusivirta, Sanna; Sawicki, Janet; Wei, Gong-Hong; Kuznetsov, Sergey G.

2014-04-01

Multiple observations suggest a cell type-specific role for TP53 in mammary epithelia. We developed an in vitro assay, in which primary mouse mammary epithelial cells (mMECs) progressed from lumenal to basal-like phenotypes based on expression of Krt18 or ΔNp63, respectively. Such transition was markedly delayed in Trp53-/- mMECs suggesting that Trp53 is required for specification of the basal, but not lumenal cells. Evidence from human basal-like cell lines suggests that TP53 may support the activity of ΔNp63 by preventing its translocation from nucleoplasm into nucleoli. In human lumenal cells, activation of TP53 by inhibiting MDM2 or BRCA1 restored the nucleoplasmic expression of ΔNp63. Trp53-/- mMECs eventually lost epithelial features resulting in upregulation of MDM2 and translocation of ΔNp63 into nucleoli. We propose that TP63 may contribute to TP53-mediated oncogenic transformation of epithelial cells and shed light on tissue- and cell type-specific biases observed for TP53-related cancers.

A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer.

Science.gov (United States)

Neuzillet, Yann; Paoletti, Xavier; Ouerhani, Slah; Mongiat-Artus, Pierre; Soliman, Hany; de The, Hugues; Sibony, Mathilde; Denoux, Yves; Molinie, Vincent; Herault, Aurélie; Lepage, May-Linda; Maille, Pascale; Renou, Audrey; Vordos, Dimitri; Abbou, Claude-Clément; Bakkar, Ashraf; Asselain, Bernard; Kourda, Nadia; El Gaaied, Amel; Leroy, Karen; Laplanche, Agnès; Benhamou, Simone; Lebret, Thierry; Allory, Yves; Radvanyi, François

2012-01-01

TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications) and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR = 0.25 [0.18-0.37], p = 0.0001) or for pT1 tumours alone (OR = 0.47 [0.28-0.79], p = 0.0009). However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR = 0.56 [0.23-1.36] (p = 0.12) and OR = 0.99 [0.37-2.7] (p = 0.35), respectively). After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4). These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.

Defects in mitophagy promote redox-driven metabolic syndrome in the absence of TP53INP1.

Science.gov (United States)

Seillier, Marion; Pouyet, Laurent; N'Guessan, Prudence; Nollet, Marie; Capo, Florence; Guillaumond, Fabienne; Peyta, Laure; Dumas, Jean-François; Varrault, Annie; Bertrand, Gyslaine; Bonnafous, Stéphanie; Tran, Albert; Meur, Gargi; Marchetti, Piero; Ravier, Magalie A; Dalle, Stéphane; Gual, Philippe; Muller, Dany; Rutter, Guy A; Servais, Stéphane; Iovanna, Juan L; Carrier, Alice

2015-06-01

The metabolic syndrome covers metabolic abnormalities including obesity and type 2 diabetes (T2D). T2D is characterized by insulin resistance resulting from both environmental and genetic factors. A genome-wide association study (GWAS) published in 2010 identified TP53INP1 as a new T2D susceptibility locus, but a pathological mechanism was not identified. In this work, we show that mice lacking TP53INP1 are prone to redox-driven obesity and insulin resistance. Furthermore, we demonstrate that the reactive oxygen species increase in TP53INP1-deficient cells results from accumulation of defective mitochondria associated with impaired PINK/PARKIN mitophagy. This chronic oxidative stress also favors accumulation of lipid droplets. Taken together, our data provide evidence that the GWAS-identified TP53INP1 gene prevents metabolic syndrome, through a mechanism involving prevention of oxidative stress by mitochondrial homeostasis regulation. In conclusion, this study highlights TP53INP1 as a molecular regulator of redox-driven metabolic syndrome and provides a new preclinical mouse model for metabolic syndrome clinical research. © 2015 The Authors. Published under the terms of the CC BY 4.0 license.

TP53 and ATM mRNA expression in skin and skeletal muscle after low-level laser exposure.

Science.gov (United States)

Guedes de Almeida, Luciana; Sergio, Luiz Philippe da Silva; de Paoli, Flavia; Mencalha, Andre Luiz; da Fonseca, Adenilson de Souza

2017-08-01

Low-level lasers are widespread in regenerative medicine, but the molecular mechanisms involved in their biological effects are not fully understood, particularly those on DNA stability. Therefore, this study aimed to investigate mRNA expression of genes related to DNA genomic stability in skin and skeletal muscle tissue from Wistar rats exposed to low-level red and infrared lasers. For this, TP53 (Tumor Protein 53) and ATM (Ataxia Telangiectasia Mutated gene) mRNA expressions were evaluated by real-time quantitative PCR (RT-qPCR) technique 24 hours after low-level red and infrared laser exposure. Our data showed that relative TP53 mRNA expression was not significantly altered in both tissues exposed to lasers. For ATM, relative mRNA expression in skin tissue was not significantly altered, but in muscle tissue, laser exposure increased relative ATM mRNA expression. Low-level red and infrared laser radiations alter ATM mRNA expression related to DNA stability in skeletal muscle tissue.

TP53 genetic polymorphisms, interactions with lifestyle factors and lung cancer risk: a case control study in a Chinese population

International Nuclear Information System (INIS)

Li, Yanli; Su, Jia; Cai, Lin; Yu, Shunzhang; Zhang, Zuo-Feng; Mu, Lina; Chang, Shen-Chih; Niu, Rungui; Liu, Li; Crabtree-Ide, Christina R; Zhao, Baoxing; Shi, Jianping; Han, Xiaoyou; Li, Jiawei

2013-01-01

A pathway-based genotyping analysis suggested rs2078486 was a novel TP53 SNP, but very few studies replicate this association. TP53 rs1042522 is the most commonly studied SNP, but very few studies examined its potential interaction with environmental factors in relation to lung cancer risk. This study aims to examine associations between two TP53 single-nucleotide polymorphisms (SNPs) (rs2078486, rs1042522), their potential interaction with environmental factors and risk of lung cancer. A case–control study was conducted in Taiyuan, China. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Multiplicative and additive interactions between TP53 SNPs and lifestyle factors were evaluated. Variant TP53 rs2078486 SNP was significantly associated with elevated lung cancer risk among smokers (OR: 1.70, 95% CI: 1.08 - 2.67) and individuals with high indoor air pollution exposure (OR: 1.51, 95% CI: 1.00-2.30). Significant or borderline significant multiplicative and additive interactions were found between TP53 rs2078486 polymorphism with smoking and indoor air pollution exposure. The variant genotype of TP53 SNP rs1042522 significantly increased lung cancer risk in the total population (OR: 1.57, 95% CI: 1.11-2.21), but there was no evidence of heterogeneity among individuals with different lifestyle factors. This study confirmed that TP53 rs2078486 SNP is potentially a novel TP53 SNP that may affect lung cancer risk. Our study also suggested potential synergetic effects of TP53 rs2078486 SNP with smoking and indoor air pollution exposure on lung cancer risk

Review of prognostic and predictive aspects of mutated TP53 in Wilms’ tumor biology with morphological report and molecular analysis of 37-year-old man’s nephroblastoma

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Andrzej Wincewicz

2017-02-01

Full Text Available Here we review prognostic and predictive aspects of mutated TP53 in Wilms’ tumor biology on the basis of the morphological report and molecular analysis of adult nephroblastoma (diffuse blastemal pattern of a 37-year-old man. Among quite different proteins, TP53 affects expression of several genes such as hypoxia inducible proteins GLUT1 and EPO as well as multidrug resistance (MDR mediated by P-glycoprotein (Pgp/MDR1 and multidrug-resistant related protein (MRP1, with certain clinical implications. TP53 mutation was found both in our primary tumor (c.746G>T p.R249M frequency 92% and in nodal metastasis (c.746G>T p.R249M frequency 90%, and the common polymorphism p.P72R in the same gene was revealed with frequency of about 97% in both primary tumor and metastatic disease with appliance of NGS technology (IonTorrent – LifeTechnology using Ion AmpliSeq Cancer Hotspot Panel v2.

Association of the germline TP53 R337H mutation with breast cancer in southern Brazil

International Nuclear Information System (INIS)

Assumpção, Juliana G; Zeferino, Luiz Carlos; Dufloth, Rozany M; Brandalise, Silvia Regina; Yunes, José Andres; Seidinger, Ana Luíza; Mastellaro, Maria José; Ribeiro, Raul C; Zambetti, Gerard P; Ganti, Ramapriya; Srivastava, Kumar; Shurtleff, Sheila; Pei, Deqing

2008-01-01

The germline TP53-R337H mutation is strongly associated with pediatric adrenocortical tumors (ACT) in southern Brazil; it has low penetrance and limited tissue specificity in most families and therefore is not associated with Li-Fraumeni syndrome. However, other tumor types, mainly breast cancer, have been observed in carriers of several unrelated kindreds, raising the possibility that the R337H mutation may also contribute to breast tumorigenesis in a genetic background-specific context. We conducted a case-control study to determine the prevalence of the R337H mutation by sequencing TP53 exon 10 in 123 women with breast cancer and 223 age- and sex-matched control subjects from southern Brazil. Fisher's test was used to compare the prevalence of the R337H. The R337H mutation was found in three patients but in none of the controls (p = 0.0442). Among the carriers, two had familial history of cancer meeting the Li-Fraumeni-like criteria. Remarkably, tumors in each of these three cases underwent loss of heterozygosity by eliminating the mutant TP53 allele rather than the wild-type allele. Polymorphisms were identified within the TP53 (R72P and Ins16) and MDM2 (SNP309) genes that may further diminish TP53 tumor suppressor activity. These results demonstrate that the R337H mutation can significantly increase the risk of breast cancer in carriers, which likely depends on additional cooperating genetic factors. These findings are also important for understanding how low-penetrant mutant TP53 alleles can differentially influence tumor susceptibility

Extremely high Tp53 mutation load in esophageal squamous cell carcinoma in Golestan Province, Iran.

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Behnoush Abedi-Ardekani

Full Text Available BACKGROUND: Golestan Province in northeastern Iran has one of the highest incidences of esophageal squamous cell carcinoma (ESCC in the world with rates over 50 per 100,000 person-years in both sexes. We have analyzed TP53 mutation patterns in tumors from this high-risk geographic area in search of clues to the mutagenic processes involved in causing ESCC. METHODOLOGY/PRINCIPAL FINDINGS: Biopsies of 119 confirmed ESCC tumor tissue from subjects enrolled in a case-control study conducted in Golestan Province were analyzed by direct sequencing of TP53 exons 2 through 11. Immunohistochemical staining for p53 was carried out using two monoclonal antibodies, DO7 and 1801. A total of 120 TP53 mutations were detected in 107/119 cases (89.9%, including 11 patients with double or triple mutations. The mutation pattern was heterogeneous with infrequent mutations at common TP53 "hotspots" but frequent transversions potentially attributable to environmental carcinogens forming bulky DNA adducts, including 40% at bases known as site of mutagenesis by polycyclic aromatic hydrocarbons (PAHs. Mutations showed different patterns according to the reported temperature of tea consumption, but no variation was observed in relation to ethnicity, tobacco or opium use, and alcoholic beverage consumption or urban versus rural residence. CONCLUSION/SIGNIFICANCE: ESCC tumors in people from Golestan Province show the highest rate of TP53 mutations ever reported in any cancer anywhere. The heterogeneous mutation pattern is highly suggestive of a causative role for multiple environmental carcinogens, including PAHs. The temperature and composition of tea may also influence mutagenesis.

New recurrent deletions in the PPARgamma and TP53 genes are associated with childhood myelodysplastic syndrome

DEFF Research Database (Denmark)

Silveira, Cássia G T; Oliveira, Fábio M; Valera, Elvis T

2009-01-01

Myelodysplastic syndrome (MDS) is a rare hematological malignancy in children. It was performed FISH analysis in 19 pediatric MDS patients to investigate deletions involving the PPARgamma and TP53 genes. Significant losses in the PPARgamma gene and deletions in the tumor suppressor gene TP53 were...

A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer.

Directory of Open Access Journals (Sweden)

Yann Neuzillet

Full Text Available TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR = 0.25 [0.18-0.37], p = 0.0001 or for pT1 tumours alone (OR = 0.47 [0.28-0.79], p = 0.0009. However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR = 0.56 [0.23-1.36] (p = 0.12 and OR = 0.99 [0.37-2.7] (p = 0.35, respectively. After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4. These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.

Association of the germline TP53 R337H mutation with breast cancer in southern Brazil

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Srivastava Kumar

2008-12-01

Full Text Available Abstract Background The germline TP53-R337H mutation is strongly associated with pediatric adrenocortical tumors (ACT in southern Brazil; it has low penetrance and limited tissue specificity in most families and therefore is not associated with Li-Fraumeni syndrome. However, other tumor types, mainly breast cancer, have been observed in carriers of several unrelated kindreds, raising the possibility that the R337H mutation may also contribute to breast tumorigenesis in a genetic background-specific context. Methods We conducted a case-control study to determine the prevalence of the R337H mutation by sequencing TP53 exon 10 in 123 women with breast cancer and 223 age- and sex-matched control subjects from southern Brazil. Fisher's test was used to compare the prevalence of the R337H. Results The R337H mutation was found in three patients but in none of the controls (p = 0.0442. Among the carriers, two had familial history of cancer meeting the Li-Fraumeni-like criteria. Remarkably, tumors in each of these three cases underwent loss of heterozygosity by eliminating the mutant TP53 allele rather than the wild-type allele. Polymorphisms were identified within the TP53 (R72P and Ins16 and MDM2 (SNP309 genes that may further diminish TP53 tumor suppressor activity. Conclusion These results demonstrate that the R337H mutation can significantly increase the risk of breast cancer in carriers, which likely depends on additional cooperating genetic factors. These findings are also important for understanding how low-penetrant mutant TP53 alleles can differentially influence tumor susceptibility.

Clinical Impact of TP53 Gene Mutations in Diffuse Large B-Cell Lymphoma (DLBCL)

DEFF Research Database (Denmark)

Young, Ken H; Patten, Nancy; Truong, Sim

2009-01-01

Mutations of the TP53 tumor suppressor gene are associated with a poor clinical outcome in DLBCL patients treated with CHOP. The impact of TP53 mutations on clinical outcome of DLBCL patients treated with Rituxan-CHOP has not been comprehensively analyzed. The purpose of this study was to analyze...

TP53 p.R337H is a conditional cancer-predisposing mutation: further evidence from a homozygous patient

International Nuclear Information System (INIS)

Giacomazzi, Juliana; Hainaut, Pierre; Ashton-Prolla, Patricia; Selistre, Simone; Duarte, Juliana; Ribeiro, Jorge Pinto; Vieira, Paulo JC; Souza Macedo, Gabriel de; Rossi, Cristina; Czepielewski, Mauro; Netto, Cristina Brinkmann Oliveira

2013-01-01

Adrenocortical carcinomas (ACCs) are among the most common childhood cancers occurring in infants affected with the Li-Fraumeni and Li- Fraumeni-like (LFS/LFL) syndromes, which are caused by dominant germline mutations in the TP53 gene. In Brazil, a particular mutation, occurring in the tetramerisation domain of the gene, p.R337H, is exceedingly common due to a founder effect and is strongly associated with ACC. In this report, we describe the phenotype and long-term clinical follow-up of a female child diagnosed with ACC and homozygous for the TP53 p.R337H founder mutation. At age 11 months, the patient was diagnosed with a virilising anaplastic adrenal cortical tumour, which was completely excised without disturbing the adrenal capsule. Family history was consistent with an LFL tumour pattern, and genotyping identified the TP53 p.R337H mutation in both alleles in genomic DNA from lymphocytes and fibroblasts. Haplotype analysis confirmed the occurrence of the mutation in the same founder haplotype previously described in other Brazilian patients. No other germline or somatic TP53 mutations or rearrangements were identified. At age 9 years, the child was asymptomatic and had no evidence of endocrine derangements. Full body and brain magnetic resonance imaging (MRI) failed to detect any suspicious proliferative lesions, and cardiopulmonary exercise testing results were within the normal reference for the child’s age, ruling out a major exercise capacity deficiency. This is the first clinical and aerobic functional capacity documentation of a patient who carries two mutant TP53 alleles and no wild-type allele. Our results support the hypothesis that TP53 p.R337H, the most common TP53 mutation ever described in any population, is a conditional mutant. Furthermore, our observations over a long period of clinical follow-up suggest that TP53 p.R337H homozygotes do not have a more severe disease phenotype than do heterozygote carriers of the same mutation. Patients with

The Neuronal Ischemic Tolerance Is Conditioned by the Tp53 Arg72Pro Polymorphism.

Science.gov (United States)

Ramos-Araque, Maria E; Rodriguez, Cristina; Vecino, Rebeca; Cortijo Garcia, Elisa; de Lera Alfonso, Mercedes; Sanchez Barba, Mercedes; Colàs-Campàs, Laura; Purroy, Francisco; Arenillas, Juan F; Almeida, Angeles; Delgado-Esteban, Maria

2018-04-23

Cerebral preconditioning (PC) confers endogenous brain protection after stroke. Ischemic stroke patients with a prior transient ischemic attack (TIA) may potentially be in a preconditioned state. Although PC has been associated with the activation of pro-survival signals, the mechanism by which preconditioning confers neuroprotection is not yet fully clarified. Recently, we have described that PC-mediated neuroprotection against ischemic insult is promoted by p53 destabilization, which is mediated by its main regulator MDM2. Moreover, we have previously described that the human Tp53 Arg72Pro single nucleotide polymorphism (SNP) controls susceptibility to ischemia-induced neuronal apoptosis and governs the functional outcome of patients after stroke. Here, we studied the contribution of the human Tp53 Arg72Pro SNP on PC-induced neuroprotection after ischemia. Our results showed that cortical neurons expressing the Pro72-p53 variant exhibited higher PC-mediated neuroprotection as compared with Arg72-p53 neurons. PC prevented ischemia-induced nuclear and cytosolic p53 stabilization in Pro72-p53 neurons. However, PC failed to prevent mitochondrial p53 stabilization, which occurs in Arg72-p53 neurons after ischemia. Furthermore, PC promoted neuroprotection against ischemia by controlling the p53/active caspase-3 pathway in Pro72-p53, but not in Arg72-p53 neurons. Finally, we found that good prognosis associated to TIA within 1 month prior to ischemic stroke was restricted to patients harboring the Pro72 allele. Our findings demonstrate that the Tp53 Arg72Pro SNP controls PC-promoted neuroprotection against a subsequent ischemic insult by modulating mitochondrial p53 stabilization and then modulates TIA-induced ischemic tolerance.

A novel splice mutation in the TP53 gene associated with Leydig cell tumor and primitive neuroectodermal tumor

DEFF Research Database (Denmark)

Stecher, Chalotte Willemann; Grønbaek, Kirsten; Hasle, Henrik

2008-01-01

A 20-month-old boy presented with precocious puberty due to a Leydig cell tumor, and at the age of 6 years with a primitive neuroectodermal brain-tumor (PNET). A novel splice site mutation of the TP53-gene, likely to be associated with a nonfunctional protein, was found in the proband, his father...

Rhabdomyosarcoma-associated renal cell carcinoma: a link with constitutional Tp53 mutation.

LENUS (Irish Health Repository)

Curry, Sarah

2012-02-01

The 2004 World Health Organization classification includes the new entity "neuroblastoma-associated renal cell carcinoma." The pathogenetic link between these entities is unknown as yet. The patient reported herein developed renal cell carcinoma after anaplastic embryonal rhabdomyosarcoma, a previously unknown association. The 2nd malignancy developed very soon after the 1st one, prompting concern for inherent cancer predisposition rather than a therapy-induced 2nd malignancy. A variety of features raised suspicion for Tp53 mutation, and indeed a pathogenic germline Tp53 mutation was identified in this child, despite a negative family history for Li-Fraumeni syndrome. Consideration of underlying predisposition is advocated in the context of rapid evolution of 2nd childhood malignancy.

The association of TP53 mutations with the resistance of colorectal carcinoma to the insulin-like growth factor-1 receptor inhibitor picropodophyllin

International Nuclear Information System (INIS)

Wang, Quan; Wei, Feng; Lv, Guoyue; Li, Chunsheng; Liu, Tongjun; Hadjipanayis, Costas G; Zhang, Guikai; Hao, Chunhai; Bellail, Anita C

2013-01-01

There is growing evidence indicating the insulin-like growth factor 1 receptor (IGF-1R) plays a critical role in the progression of human colorectal carcinomas. IGF-1R is an attractive drug target for the treatment of colon cancer. Picropodophyllin (PPP), of the cyclolignan family, has recently been identified as an IGF-1R inhibitor. The aim of this study is to determine the therapeutic response and mechanism after colorectal carcinoma treatment with PPP. Seven colorectal carcinoma cell lines were treated with PPP. Following treatment, cells were analyzed for growth by a cell viability assay, sub-G1 apoptosis by flow cytometry, caspase cleavage and activation of AKT and extracellular signal-regulated kinase (ERK) by western blot analysis. To examine the in vivo therapeutic efficacy of PPP, mice implanted with human colorectal carcinoma xenografts underwent PPP treatment. PPP treatment blocked the phosphorylation of IGF-1R, AKT and ERK and inhibited the growth of TP53 wild-type but not mutated colorectal carcinoma cell lines. The treatment of PPP also induced apoptosis in TP53 wild-type cells as evident by the presence of sub-G1 cells and the cleavage of caspase-9, caspase-3, DNA fragmentation factor-45 (DFF45), poly (ADP-ribose) polymerase (PARP), and X-linked inhibitor of apoptosis protein (XIAP). The loss of BAD phosphorylation in the PPP-treated TP53 wild type cells further suggested that the treatment induced apoptosis through the BAD-mediated mitochondrial pathway. In contrast, PPP treatment failed to induce the phosphorylation of AKT and ERK and caspase cleavage in TP53 mutated colorectal carcinoma cell lines. Finally, PPP treatment suppressed the growth of xenografts derived from TP53 wild type but not mutated colorectal carcinoma cells. We report the association of TP53 mutations with the resistance of treatment of colorectal carcinoma cells in culture and in a xenograft mouse model with the IGF-1R inhibitor PPP. TP53 mutations often occur in colorectal

Identification of colorectal cancer patients with tumors carrying the TP53 mutation on the codon 72 proline allele that benefited most from 5-fluorouracil (5-FU) based postoperative chemotherapy

International Nuclear Information System (INIS)

Godai, Ten-i; Sakuma, Yuji; Tsuchiya, Eiju; Kameda, Yoichi; Akaike, Makoto; Miyagi, Yohei; Suda, Tetsuji; Sugano, Nobuhiro; Tsuchida, Kazuhito; Shiozawa, Manabu; Sekiguchi, Hironobu; Sekiyama, Akiko; Yoshihara, Mitsuyo; Matsukuma, Shoichi

2009-01-01

Although postoperative chemotherapy is widely accepted as the standard modality for Dukes' stage C or earlier stage colorectal cancer (CRC) patients, biomarkers to predict those who may benefit from the therapy have not been identified. Previous in vitro and clinical investigations reported that CRC patients with wild-type p53 gene (TP53)-tumors benefit from 5-fluorouracil (5-FU) based chemotherapy, while those with mutated TP53-tumors do not. However, these studies evaluated the mutation-status of TP53 by immunohistochemistry with or without single-strand conformation polymorphism, and the mutation frequency was different from study to study. In addition, the polymorphic status at p53 codon 72, which results in arginine or proline residues (R72P) and is thought to influence the function of the protein significantly, was not examined. To evaluate the significance of the TP53 mutation as a molecular marker to predict the prognosis of CRC patients, especially those who received postoperative chemotherapy, we examined the mutation by direct sequencing from fresh CRC tumors and evaluated the R72P polymorphism of the mutated TP53 by a combined mutant allele- and polymorphic allele-specific polymerase chain reaction (PCR). The TP53 mutation occurred in 147 (70%) of 211 Japanese CRC tumors. The mutation was observed in 93 (63%) tumors on the R72 allele and in 54 (37%) tumors on the P72 allele. Although the alterations to TP53 have no prognostic significance for CRC patients overall, we found that Dukes' stage C CRC patients who did not receive postoperative chemotherapy and carried the mutated TP53-R72 showed significantly longer survival times than those with the mutated TP53-P72 when evaluated by overall survival (p = 0.012). Using a combined mutant allele- and polymorphic allele-specific PCR, we defined the codon 72 polymorphic status of the TP53 mutated allele in Japanese CRC patients. We raised a possibility that Dukes' stage C colorectal cancer

Mutations and polymorphisms in TP53 gene--an overview on the role in colorectal cancer

Czech Academy of Sciences Publication Activity Database

Naccarati, Alessio; Poláková, Veronika; Pardini, Barbara; Vodičková, Ludmila; Hemminki, K.; Kumar, R.; Vodička, Pavel (ed.)

2012-01-01

Roč. 27, č. 2 (2012), s. 211-218 ISSN 0267-8357 R&D Projects: GA ČR GP305/09/P194; GA ČR GAP304/10/1286 Grant - others:GA UK(CZ) GA96908/B/2008 Institutional research plan: CEZ:AV0Z50390512 Keywords : TP53 mutations * TP53 polymorphisms * cancer risk Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.500, year: 2012

Contribution of germline TP53 variants and assessment of HER-2 status among young breast cancer patients in Malaysia

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Shao Yan Lau

2017-12-01

Full Text Available Background: Li-Fraumeni Syndrome (LFS is caused by a mutation in the TP53 tumour suppressor gene. This rare hereditary condition predisposes individuals to an increased risk of cancers including breast cancer in women at a relatively young age, which accounts for nearly 25%–30% of all LFS‑associated cancers. Studies have shown that breast tumours in women with a germline TP53 deleterious variants are associated with a human epidermal growth factor receptor 2 (HER2-positive phenotype. Taken together, this study aimed to investigate the contribution of germline TP53 variants and its association with tumour HER-2 status in a cohort of young women with breast cancer. Methods: From 2002 to 2017, 4048 women with breast cancer treated at University Malaya Medical Centre or Sime Darby Medical Centre participated in the Malaysian Breast Cancer Genetics Study. Of which, 87 patients were diagnosed before 30 years of age. All patients were analysed for germline TP53 single nucleotide variants, small insertions or deletions by amplicon‑based targeted sequencing and validated by Sanger sequencing. DNA from patients who tested negative for sequencing were subsequently evaluated for the presence of TP53 exon deletions or duplications by multiplex ligation‑dependent probe amplification. HER-2 status of breast tumours was defined by immunohistochemistry, fluorescence in situ hybridisation and/or silver in situ hybridisation. Results: 5 distinct TP53 variants were detected in 5 individuals. 3 out of 5 TP53 variants were classified as frameshift mutations, one nonsense mutation and one in-frame duplication. Variants in other genes were detected in 17 individuals. No large genomic rearrangements were detected in the remaining 65 sequencing-negative patients. The assessment of HER-2 status will be presented. Conclusions: Our results suggest that alterations in TP53 gene were identified in approximately 5.7% (5/87 of this cohort of young women with breast

TP53 mutation and human papilloma virus status of oral squamous cell carcinomas in young adult patients

NARCIS (Netherlands)

Braakhuis, B.J.M.; Rietbergen, M.M.; Buijze, M.; Snijders, P.J.F.; Bloemena, E.; Brakenhoff, R.H.; Leemans, C.R.

2014-01-01

Objective Little is known about the molecular carcinogenesis of oral squamous cell carcinoma (OSCC) in young adult patients. The aim of this study was to investigate the detailed TP53 mutation and human papilloma virus (HPV) status of OSCC in patients, younger than 45 years. Methods TP53 mutations

Structural and dynamics studies of a truncated variant of CI repressor from bacteriophage TP901-1

DEFF Research Database (Denmark)

Rasmussen, Kim Krighaar; Frandsen, Kristian E. H.; Erba, Elisabetta Boeri

2016-01-01

The CI repressor from the temperate bacteriophage TP901-1 consists of two folded domains, an N-terminal helix-turn-helix DNA-binding domain (NTD) and a C-terminal oligomerization domain (CTD), which we here suggest to be further divided into CTD1 and CTD2. Full-length CI is a hexameric protein......, whereas a truncated version, CIΔ58, forms dimers. We identify the dimerization region of CIΔ58 as CTD1 and determine its secondary structure to be helical both within the context of CIΔ58 and in isolation. To our knowledge this is the first time that a helical dimerization domain has been found in a phage...... repressor. We also precisely determine the length of the flexible linker connecting the NTD to the CTD. Using electrophoretic mobility shift assays and native mass spectrometry, we show that CIΔ58 interacts with the O-L operator site as one dimer bound to both half-sites, and with much higher affinity than...

TP53 codon 72 polymorphism as a risk factor for cardiovascular disease in a Brazilian population

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M.A.C. Smith

2007-11-01

Full Text Available TP53, a tumor suppressor gene, has a critical role in cell cycle, apoptosis and cell senescence and participates in many crucial physiological and pathological processes. Identification of TP53 polymorphism in older people and age-related diseases may provide an understanding of its physiology and pathophysiological role as well as risk factors for complex diseases. TP53 codon 72 (TP53:72 polymorphism was investigated in 383 individuals aged 66 to 97 years in a cohort from a Brazilian Elderly Longitudinal Study. We investigated allele frequency, genotype distribution and allele association with morbidities such as cardiovascular disease, type II diabetes, obesity, neoplasia, low cognitive level (dementia, and depression. We also determined the association of this polymorphism with serum lipid fractions and urea, creatinine, albumin, fasting glucose, and glycated hemoglobin levels. DNA was isolated from blood cells, amplified by PCR using sense 5'-TTGCCGTCCCAAGCAATGGATGA-3' and antisense 5'-TCTGGGAAGGGACAGAAGATGAC-3' primers and digested with the BstUI enzyme. This polymorphism is within exon 4 at nucleotide residue 347. Descriptive statistics, logistic regression analysis and Student t-test using the multiple comparison test were used. Allele frequencies, R (Arg = 0.69 and P (Pro = 0.31, were similar to other populations. Genotype distributions were within Hardy-Weinberg equilibrium. This polymorphism did not show significant association with any age-related disease or serum variables. However, R allele carriers showed lower HDL levels and a higher frequency of cardiovascular disease than P allele subjects. These findings may help to elucidate the physiopathological role of TP53:72 polymorphism in Brazilian elderly people.

Towards Prognostic Profiling of Non-Small Cell Lung Cancer: New Perspectives on the Relevance of Polo-Like Kinase 1 Expression, the TP53 Mutation Status and Hypoxia

Science.gov (United States)

Van den Bossche, Jolien; Deben, Christophe; Op de Beeck, Ken; Deschoolmeester, Vanessa; Hermans, Christophe; De Pauw, Ines; Jacobs, Julie; Van Schil, Paul; Vermorken, Jan Baptist; Pauwels, Patrick; Peeters, Marc; Lardon, Filip; Wouters, An

2017-01-01

Background: Currently, prognosis of non-small cell lung cancer (NSCLC) patients is based on clinicopathological factors, including TNM stage. However, there are considerable differences in patient outcome within a similar staging group, even when patients received identical treatments. In order to improve prognostic predictions and to guide treatment options, additional parameters influencing outcome are required. Polo-like kinase 1 (Plk1), a master regulator of mitotic cell division and the DNA damage response, is considered as a new potential biomarker in this research area. While several studies reported Plk1 overexpression in a broad range of human malignancies, inconsistent results were published regarding the clinical significance hereof. A prognostic panel, consisting of Plk1 and additional biomarkers that are related to the Plk1 pathway, might further improve prediction of patient prognosis. Methods: In this study, we evaluated for the first time the prognostic value of Plk1 mRNA and protein expression in combination with the TP53 mutation status (next generation sequencing), induction of apoptotic cell death (immunohistochemistry for cleaved caspase 3) and hypoxia (immunohistochemistry for carbonic anhydrase IX (CA IX)) in 98 NSCLC adenocarcinoma patients. Results: Both Plk1 mRNA and protein expression and CA IX protein levels were upregulated in the majority of tumor samples. Plk1 mRNA and protein expression levels were higher in TP53 mutant samples, suggesting that Plk1 overexpression is, at least partially, the result of loss of functional p53 (<0.05). Interestingly, the outcome of patients with both Plk1 mRNA and CA IX protein overexpression, who also harbored a TP53 mutation, was much worse than that of patients with aberrant expression of only one of the three markers (p=0.001). Conclusion: The combined evaluation of Plk1 mRNA expression, CA IX protein expression and TP53 mutations shows promise as a prognostic panel in NSCLC patients. Moreover

The Role of Tumor Protein 53 Mutations in Common Human Cancers and Targeting the Murine Double Minute 2–P53 Interaction for Cancer Therapy

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Tayebeh Hamzehloie

2012-03-01

Full Text Available The gene TP53 (also known as protein 53 or tumor protein 53, encoding transcription factor P53, is mutated or deleted in half of human cancers, demonstrating the crucial role of P53 in tumor suppression. There are reports of nearly 250 independent germ line TP53 mutations in over 100 publications. The P53 protein has the structure of a transcription factor and, is made up of several domains. The main function of P53 is to organize cell defense against cancerous transformation. P53 is a potent transcription factor that is activated in response to diverse stresses, leading to the induction of cell cycle arrest, apoptosis or senescence. The P53 tumor suppressor is negatively regulated in cells by the murine double minute 2 (MDM2 protein. Murine double minute 2 favors its nuclear export, and stimulates its degradation. Inhibitors of the P53-MDM2 interaction might be attractive new anticancer agents that could be used to activate wild-type P53 in tumors. Down regulation of MDM2 using an small interfering RNA (siRNA approach has recently provided evidence for a new role of MDM2 in the P53 response, by modulating the inhibition of the cyclin dependent kinase 2 (cdk2 by P21/WAF1 (also known as cyclin-dependent kinase inhibitor 1 or CDK-interacting protein 1.

TP53 genetic polymorphisms, interactions with lifestyle factors and lung cancer risk: a case control study in a Chinese population

OpenAIRE

Li, Yanli; Chang, Shen-Chih; Niu, Rungui; Liu, Li; Crabtree-Ide, Christina R; Zhao, Baoxing; Shi, Jianping; Han, Xiaoyou; Li, Jiawei; Su, Jia; Cai, Lin; Yu, Shunzhang; Zhang, Zuo-Feng; Mu, Lina

2013-01-01

Abstract Background A pathway-based genotyping analysis suggested rs2078486 was a novel TP53 SNP, but very few studies replicate this association. TP53 rs1042522 is the most commonly studied SNP, but very few studies examined its potential interaction with environmental factors in relation to lung cancer risk. This study aims to examine associations between two TP53 single-nucleotide polymorphisms (SNPs) (rs2078486, rs1042522), their potential interac...

TP53 alterations in Wilms tumour represent progression events with strong intratumour heterogeneity that are closely linked but not limited to anaplasia

OpenAIRE

Wegert, Jenny; Vokuh, Christian; Ziegler, Barbara; Ernestus, Karen; Leuschner, Ivo; Furtwängler, Rhoikos; Graf, Norbert; Gessler, Manfred

2018-01-01

TP53 mutations have been associated with anaplasia in Wilms tumour, which conveys a high risk for relapse and fatal outcome. Nevertheless, TP53 alterations have been reported in no more than 60% of anaplastic tumours, and recent data have suggested their presence in tumours that do not fulfil the criteria for anaplasia, questioning the clinical utility of TP53 analysis. Therefore, we characterized the TP53 status in 84 fatal cases of Wilms tumour, irrespective of histological subtype. We iden...

TP53 alterations in Wilms tumour represent progression events with strong intratumour heterogeneity that are closely linked but not limited to anaplasia

OpenAIRE

Wegert, Jenny; Vokuhl, Christian; Ziegler, Barbara; Ernestus, Karen; Leuschner, Ivo; Furtwängler, Rhoikos; Graf, Norbert; Gessler, Manfred

2017-01-01

Abstract TP53 mutations have been associated with anaplasia in Wilms tumour, which conveys a high risk for relapse and fatal outcome. Nevertheless, TP53 alterations have been reported in no more than 60% of anaplastic tumours, and recent data have suggested their presence in tumours that do not fulfil the criteria for anaplasia, questioning the clinical utility of TP53 analysis. Therefore, we characterized the TP53 status in 84 fatal cases of Wilms tumour, irrespective of histological subtype...

Significance of TP53 mutation in Wilms tumors with diffuse anaplasia : A report from the Children's Oncology Group

NARCIS (Netherlands)

Ooms, Ariadne H A G; Gadd, Samantha; Gerhard, Daniela S.; Smith, Malcolm A.; Guidry Auvil, Jaime M.; Meerzaman, Daoud; Chen, Qing Rong; Hsu, Chih Hao; Yan, Chunhua; Nguyen, Cu; Hu, Ying; Ma, Yussanne; Zong, Zusheng; Mungall, Andrew J.; Moore, Richard A.; Marra, Marco A.; Huff, Vicki; Dome, Jeffrey S.; Chi, Yueh Yun; Tian, Jing; Geller, James I.; Mullighan, Charles G.; Ma, Jing; Wheeler, David A.; Hampton, Oliver A.; Walz, Amy L.; Van Den Heuvel-Eibrink, Marry M.; De Krijger, Ronald R.; Ross, Nicole; Gastier-Foster, Julie M.; Perlman, Elizabeth J.

2016-01-01

Purpose: To investigate the role and significance of TP53 mutation in diffusely anaplastic Wilms tumors (DAWTs). Experimental Design: All DAWTs registered on National Wilms Tumor Study-5 (n = 118) with available samples were analyzed for TP53 mutations and copy loss. Integrative genomic analysis was

TP53 alterations in Wilms tumour represent progression events with strong intratumour heterogeneity that are closely linked but not limited to anaplasia.

Science.gov (United States)

Wegert, Jenny; Vokuhl, Christian; Ziegler, Barbara; Ernestus, Karen; Leuschner, Ivo; Furtwängler, Rhoikos; Graf, Norbert; Gessler, Manfred

2017-10-01

TP53 mutations have been associated with anaplasia in Wilms tumour, which conveys a high risk for relapse and fatal outcome. Nevertheless, TP53 alterations have been reported in no more than 60% of anaplastic tumours, and recent data have suggested their presence in tumours that do not fulfil the criteria for anaplasia, questioning the clinical utility of TP53 analysis. Therefore, we characterized the TP53 status in 84 fatal cases of Wilms tumour, irrespective of histological subtype. We identified TP53 alterations in at least 90% of fatal cases of anaplastic Wilms tumour, and even more when diffuse anaplasia was present, indicating a very strong if not absolute coupling between anaplasia and deregulation of p53 function. Unfortunately, TP53 mutations do not provide additional predictive value in anaplastic tumours since the same mutation rate was found in a cohort of non-fatal anaplastic tumours. When classified according to tumour stage, patients with stage I diffuse anaplastic tumours still had a high chance of survival (87%), but this rate dropped to 26% for stages II-IV. Thus, volume of anaplasia or possible spread may turn out to be critical parameters. Importantly, among non-anaplastic fatal tumours, 26% had TP53 alterations, indicating that TP53 screening may identify additional cases at risk. Several of these non-anaplastic tumours fulfilled some criteria for anaplasia, for example nuclear unrest, suggesting that such partial phenotypes should be under special scrutiny to enhance detection of high-risk tumours via TP53 screening. A major drawback is that these alterations are secondary changes that occur only later in tumour development, leading to striking intratumour heterogeneity that requires multiple biopsies and analysis guided by histological criteria. In conclusion, we found a very close correlation between histological signs of anaplasia and TP53 alterations. The latter may precede development of anaplasia and thereby provide diagnostic value

TP53 hotspot mutations are predictive of survival in primary central nervous system lymphoma patients treated with combination chemotherapy

DEFF Research Database (Denmark)

Munch-Petersen, Helga D; Asmar, Fazila; Dimopoulos, Konstantinos

2016-01-01

regimens (high-dose methotrexate/whole brain radiation therapy, 6.0 months, or no therapy, 0.83 months), P hotspot/direct DNA contact mutations. CCT-treated patients with PCNSL harboring a hotspot/direct DNA contact MUT......-TP53 (n = 9) had a significantly worse OS and progression free survival (PFS) compared to patients with non-hotspot/non-direct DNA contact MUT-TP53 or wild-type TP53 (median PFS 4.6 versus 18.2 or 45.7 months), P = 0.041 and P = 0.00076, respectively. Multivariate Cox regression analysis confirmed...... that hotspot/direct DNA contact MUT-TP53 was predictive of poor outcome in CCT-treated PCNSL patients, P = 0.012 and P = 0.008; HR: 1.86 and 1.95, for OS and PFS, respectively. MIR34A, MIR34B/C, and DAPK promoter methylation were detected in 53/93 (57.0 %), 80/84 (95.2 %), and 70/75 (93.3 %) of the PCNSL...

Inactivation of TP53 correlates with disease progression and low miR-34a expression in previously treated chronic lymphocytic leukemia patients

DEFF Research Database (Denmark)

Dufour, Annika; Palermo, Giuseppe; Zellmeier, Evelyn

2013-01-01

In chronic lymphocytic leukemia (CLL) patients, disruptions of the TP53 tumor suppressor pathway by 17p13 deletion (del17p), somatic TP53 mutations, or downregulation of microRNA-34a have been associated with a poor prognosis. So far, the impact of the various TP53 defects has not been evaluated ...

Valproic acid treatment response in vitro is determined by TP53 status in medulloblastoma.

Science.gov (United States)

Mascaro-Cordeiro, Bruna; Oliveira, Indhira Dias; Tesser-Gamba, Francine; Pavon, Lorena Favaro; Saba-Silva, Nasjla; Cavalheiro, Sergio; Dastoli, Patrícia; Toledo, Silvia Regina Caminada

2018-05-22

Histone deacetylate inhibitors (HDACi), as valproic acid (VA), have been reported to enhance efficacy and to prevent drug resistance in some tumors, including medulloblastoma (MB). In the present study, we investigated VA role, combined to cisplatin (CDDP) in cell viability and gene expression of MB cell lines. Dose-response curve determined IC 50 values for each treatment: (1) VA single, (2) CDDP single, and (3) VA and CDDP combined. Cytotoxicity and flow cytometry evaluated cell viability after exposure to treatments. Quantitative PCR evaluated gene expression levels of AKT, CTNNB1, GLI1, KDM6A, KDM6B, NOTCH2, PTCH1, and TERT, before and after treatment. Besides, we performed next-generation sequencing (NGS) for PTCH1, TERT, and TP53 genes. The most effective treatment to reduce viability was combined for D283MED and ONS-76; and CDDP single for DAOY cells (p AKT genes were overexpressed after treatments with VA. D283MED and ONS-76 cells presented variants in TERT and PTCH1, respectively and DAOY cell line presented a TP53 mutation. MB tumors belonging to SHH molecular subgroup, with TP53 MUT , would be the ones that present high risk in relation to VA use during the treatment, while TP53 WT MBs can benefit from VA therapy, both SHH and groups 3 and 4. Our study shows a new perspective about VA action in medulloblastoma cells, raising the possibility that VA may act in different patterns. According to the genetic background of MB cell, VA can stimulate cell cycle arrest and apoptosis or induce resistance to treatment via signaling pathways activation.

Rare MDM4 gene amplification in colorectal cancer: The principle of a mutually exclusive relationship between MDM alteration and TP53 inactivation is not applicable.

Science.gov (United States)

Suda, Tetsuji; Yoshihara, Mitsuyo; Nakamura, Yoshiyasu; Sekiguchi, Hironobu; Godai, Ten-I; Sugano, Nobuhiro; Tsuchida, Kazuhito; Shiozawa, Manabu; Sakuma, Yuji; Tsuchiya, Eiju; Kameda, Yoichi; Akaike, Makoto; Matsukuma, Shoichi; Miyagi, Yohei

2011-07-01

MDM4, a homolog of MDM2, is considered a key negative regulator of p53. Gene amplification of MDM4 has been identified in a variety of tumors. MDM2 or MDM4 gene amplification is only associated with the wild-type TP53 gene in retinoblastomas, thus the amplification of the two genes is mutually exclusive. Previously, we demonstrated that MDM2 amplification and TP53 alteration were not mutually exclusive in colorectal cancer, and we identified a subset of colorectal cancer patients without alterations in either the TP53 or the MDM2 gene. In this study, we investigated the gene amplification status of MDM4 in the same set of colorectal cancer cases. Unexpectedly, MDM4 amplification was rare, detected in only 1.4% (3 out of 211) of colorectal cancer cases. All the three gene-amplified tumors also harbored TP53-inactivating mutations. This contradicts the simple mutually exclusive relationship observed in retinoblastomas. Surprisingly, two of the three MDM4-amplified tumors also demonstrated MDM2 amplification. Paradoxically, the MDM4 protein levels were decreased in the tumor tissue of the gene-amplified cases compared with levels in the matched normal mucosa. We speculate that MDM4 might play a role in colorectal carcinogenesis that is not limited to negative regulation of p53 in combination with MDM2. The functional significance of MDM4 is still unclear and further studies are needed.

Sequential mutations in Notch1, Fbxw7, and Tp53 in radiation-induced mouse thymic lymphomas.

Science.gov (United States)

Jen, Kuang-Yu; Song, Ihn Young; Banta, Karl Luke; Wu, Di; Mao, Jian-Hua; Balmain, Allan

2012-01-19

T-cell acute lymphoblastic lymphomas commonly demonstrate activating Notch1 mutations as well as mutations or deletions in Fbxw7. However, because Fbxw7 targets Notch1 for degradation, genetic alterations in these genes are expected to be mutually exclusive events in lymphomagenesis. Previously, by using a radiation-induced Tp53-deficient mouse model for T-cell acute lymphoblastic lymphoma, we reported that loss of heterozygosity at the Fbxw7 locus occurs frequently in a Tp53-dependent manner. In the current study, we show that these thymic lymphomas also commonly exhibit activating Notch1 mutations in the proline-glutamic acid-serine-threonine (PEST) domain. Moreover, concurrent activating Notch1 PEST domain mutations and single-copy deletions at the Fbxw7 locus occur with high frequency in the same individual tumors, indicating that these changes are not mutually exclusive events. We further demonstrate that although Notch1 PEST domain mutations are independent of Tp53 status, they are completely abolished in mice with germline Fbxw7 haploinsufficiency. Therefore, Notch1 PEST domain mutations only occur when Fbxw7 expression levels are intact. These data suggest a temporal sequence of mutational events involving these important cancer-related genes, with Notch1 PEST domain mutations occurring first, followed by Fbxw7 deletion, and eventually by complete loss of Tp53.

Deletion/duplication mutation screening of TP53 gene in patients with transitional cell carcinoma of urinary bladder using multiplex ligation-dependent probe amplification.

Science.gov (United States)

Bazrafshani, Mohammad Reza R; Nowshadi, Pouriaali A; Shirian, Sadegh; Daneshbod, Yahya; Nabipour, Fatemeh; Mokhtari, Maral; Hosseini, Fatemehsadat; Dehghan, Somayeh; Saeedzadeh, Abolfazl; Mosayebi, Ziba

2016-02-01

Bladder cancer is a molecular disease driven by the accumulation of genetic, epigenetic, and environmental factors. The aim of this study was to detect the deletions/duplication mutations in TP53 gene exons using multiplex ligation-dependent probe amplification (MLPA) method in the patients with transitional cell carcinoma (TCC). The achieved formalin-fixed paraffin-embedded tissues from 60 patients with TCC of bladder were screened for exonal deletions or duplications of every 12 TP53 gene exons using MLPA. The pathological sections were examined by three pathologists and categorized according to the WHO scoring guideline as 18 (30%) grade I, 22 (37%) grade II, 13 (22%) grade III, and 7 (11%) grade IV cases of TCC. None mutation changes of TP53 gene were detected in 24 (40%) of the patients. Furthermore, mutation changes including, 15 (25%) deletion, 17 (28%) duplication, and 4 (7%) both deletion and duplication cases were observed among 60 samples. From 12 exons of TP53 gene, exon 1 was more subjected to exonal deletion. Deletion of exon 1 of TP53 gene has occurred in 11 (35.4%) patients with TCC. In general, most mutations of TP53, either deletion or duplication, were found in exon 1, which was statistically significant. In addition, no relation between the TCC tumor grade and any type of mutation were observed in this research. MLPA is a simple and efficient method to analyze genomic deletions and duplications of all 12 exons of TP53 gene. The finding of this report that most of the mutations of TP53 occur in exon 1 is in contrast to that of the other reports suggesting that exons 5-8 are the most (frequently) mutated exons of TP53 gene. The mutations of exon 1 of TP53 gene may play an important role in the tumorogenesis of TCC. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Association of TP53 and MDM2 polymorphisms with survival in bladder cancer patients treated with chemoradiotherapy

International Nuclear Information System (INIS)

Shinohara, Asano; Sakano, Shigeru; Hinoda, Yuji; Nishijima, Jun; Kawai, Yoshihisa; Misumi, Taku; Nagao, Kazuhiro; Hara, Takahiko; Matsuyama, Hideyasu

2009-01-01

Platinum-based chemoradiotherapy (CRT) as bladder conservation therapy has shown promising results for muscle-invasive bladder cancer. However, CRT might diminish survival as a result of the delay in cystectomy for some patients with non-responding bladder tumors. Because the p53 tumor suppression pathway, including its MDM2 counterpart, is important in chemotherapy- and radiotherapy-associated effects, functional polymorphisms in the TP53 and MDM2 genes could influence the response to treatment and the prognosis following CRT. We investigated associations between two such polymorphisms, and p53 overexpression, and response or survival in bladder cancer patients treated with CRT. The study group comprised 96 patients who underwent CRT for transitional cell carcinoma of the bladder. Single nucleotide polymorphisms (SNPs) in TP53 (codon 72, arginine>proline) and MDM2 (SNP3O9, T>G) were genotyped using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP), and nuclear expression levels of p53 were examined using immunohistochemistry. None of the genotypes or p53 overexpression was significantly associated with response to CRT. However, patients with MDM2 T/G+G/G genotypes had improved cancer-specific survival rates after CRT (P=0.009). In multivariate analysis, the MDM2 T/G+G/G genotypes, and more than two of total variant alleles in TP53 and MDM2, were independently associated with improved cancer-specific survival (P=0.031 and P=0.015, respectively). In addition, MDM2 genotypes were significantly associated with cystectomy-free survival (P=0.030). These results suggest that the TP53 and MDM2 genotypes might be useful prognostic factors following CRT in bladder cancer, helping patient selection for bladder conservation therapy. (author)

Distinct pattern of TP53 mutations in human immunodeficiency virus-related head and neck squamous cell carcinoma.

Science.gov (United States)

Gleber-Netto, Frederico O; Zhao, Mei; Trivedi, Sanchit; Wang, Jiping; Jasser, Samar; McDowell, Christina; Kadara, Humam; Zhang, Jiexin; Wang, Jing; William, William N; Lee, J Jack; Nguyen, Minh Ly; Pai, Sara I; Walline, Heather M; Shin, Dong M; Ferris, Robert L; Carey, Thomas E; Myers, Jeffrey N; Pickering, Curtis R

2018-01-01

Human immunodeficiency virus-infected individuals (HIVIIs) have a higher incidence of head and neck squamous cell carcinoma (HNSCC), and clinical and histopathological differences have been observed in their tumors in comparison with those of HNSCC patients without a human immunodeficiency virus (HIV) infection. The reasons for these differences are not clear, and molecular differences between HIV-related HNSCC and non-HIV-related HNSCC may exist. This study compared the mutational patterns of HIV-related HNSCC and non-HIV-related HNSCC. The DNA of 20 samples of HIV-related HNSCCs and 32 samples of non-HIV-related HNSCCs was sequenced. DNA libraries covering exons of 18 genes frequently mutated in HNSCC (AJUBA, CASP8, CCND1, CDKN2A, EGFR, FAT1, FBXW7, HLA-A, HRAS, KEAP1, NFE2L2, NOTCH1, NOTCH2, NSD1, PIK3CA, TGFBR2, TP53, and TP63) were prepared and sequenced on an Ion Personal Genome Machine sequencer. DNA sequencing data were analyzed with Ion Reporter software. The human papillomavirus (HPV) status of the tumor samples was assessed with in situ hybridization, the MassARRAY HPV multiplex polymerase chain reaction assay, and p16 immunostaining. Mutation calls were compared among the studied groups. HIV-related HNSCC revealed a distinct pattern of mutations in comparison with non-HIV-related HNSCC. TP53 mutation frequencies were significantly lower in HIV-related HNSCC. Mutations in HIV+ patients tended to be TpC>T nucleotide changes for all mutated genes but especially for TP53. HNSCC in HIVIIs presents a distinct pattern of genetic mutations, particularly in the TP53 gene. HIV-related HNSCC may have a distinct biology, and an effect of the HIV virus on the pathogenesis of these tumors should not be ruled out. Cancer 2018;124:84-94. © 2017 American Cancer Society. © 2017 American Cancer Society.

Integration of TP53, DREAM, MMB-FOXM1 and RB-E2F target gene analyses identifies cell cycle gene regulatory networks.

Science.gov (United States)

Fischer, Martin; Grossmann, Patrick; Padi, Megha; DeCaprio, James A

2016-07-27

Cell cycle (CC) and TP53 regulatory networks are frequently deregulated in cancer. While numerous genome-wide studies of TP53 and CC-regulated genes have been performed, significant variation between studies has made it difficult to assess regulation of any given gene of interest. To overcome the limitation of individual studies, we developed a meta-analysis approach to identify high confidence target genes that reflect their frequency of identification in independent datasets. Gene regulatory networks were generated by comparing differential expression of TP53 and CC-regulated genes with chromatin immunoprecipitation studies for TP53, RB1, E2F, DREAM, B-MYB, FOXM1 and MuvB. RNA-seq data from p21-null cells revealed that gene downregulation by TP53 generally requires p21 (CDKN1A). Genes downregulated by TP53 were also identified as CC genes bound by the DREAM complex. The transcription factors RB, E2F1 and E2F7 bind to a subset of DREAM target genes that function in G1/S of the CC while B-MYB, FOXM1 and MuvB control G2/M gene expression. Our approach yields high confidence ranked target gene maps for TP53, DREAM, MMB-FOXM1 and RB-E2F and enables prediction and distinction of CC regulation. A web-based atlas at www.targetgenereg.org enables assessing the regulation of any human gene of interest. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Baseline results from the UK SIGNIFY study: a whole-body MRI screening study in TP53 mutation carriers and matched controls.

Science.gov (United States)

Saya, Sibel; Killick, Emma; Thomas, Sarah; Taylor, Natalie; Bancroft, Elizabeth K; Rothwell, Jeanette; Benafif, Sarah; Dias, Alexander; Mikropoulos, Christos; Pope, Jenny; Chamberlain, Anthony; Gunapala, Ranga; Izatt, Louise; Side, Lucy; Walker, Lisa; Tomkins, Susan; Cook, Jackie; Barwell, Julian; Wiles, Vicki; Limb, Lauren; Eccles, Diana; Leach, Martin O; Shanley, Susan; Gilbert, Fiona J; Hanson, Helen; Gallagher, David; Rajashanker, Bala; Whitehouse, Richard W; Koh, Dow-Mu; Sohaib, S Aslam; Evans, D Gareth; Eeles, Rosalind A

2017-07-01

In the United Kingdom, current screening guidelines for TP53 germline mutation carriers solely recommends annual breast MRI, despite the wide spectrum of malignancies typically seen in this group. This study sought to investigate the role of one-off non-contrast whole-body MRI (WB MRI) in the screening of asymptomatic TP53 mutation carriers. 44 TP53 mutation carriers and 44 population controls were recruited. Scans were read by radiologists blinded to participant carrier status. The incidence of malignancies diagnosed in TP53 mutation carriers against general population controls was calculated. The incidences of non-malignant relevant disease and irrelevant disease were measured, as well as the number of investigations required to determine relevance of findings. In TP53 mutation carriers, 6 of 44 (13.6, 95% CI 5.2-27.4%) participants were diagnosed with cancer during the study, all of which would be considered life threatening if untreated. Two were found to have two primary cancers. Two participants with cancer had abnormalities on the MRI which were initially thought to be benign (a pericardial cyst and a uterine fibroid) but transpired to be sarcomas. No controls were diagnosed with cancer. Fifteen carriers (34.1, 95% CI 20.5-49.9%) and seven controls (15.9, 95% CI 6.7-30.1%) underwent further investigations following the WB MRI for abnormalities that transpired to be benign (p = 0.049). The cancer detection rate in this group justifies a minimum baseline non-contrast WB MRI in germline TP53 mutation carriers. This should be adopted into national guidelines for management of adult TP53 mutation carriers in addition to the current practice of contrast enhanced breast MRI imaging.

Reactivating TP53 signaling by the novel MDM2 inhibitor DS-3032b as a therapeutic option for high-risk neuroblastoma

Science.gov (United States)

Arnhold, Viktor; Schmelz, Karin; Proba, Jutta; Winkler, Annika; Wünschel, Jasmin; Toedling, Joern; Deubzer, Hedwig E.; Künkele, Annette; Eggert, Angelika; Schulte, Johannes H.; Hundsdoerfer, Patrick

2018-01-01

Fewer than 50% of patients with high-risk neuroblastoma survive five years after diagnosis with current treatment protocols. Molecular targeted therapies are expected to improve survival. Although MDM2 has been validated as a promising target in preclinical models, no MDM2 inhibitors have yet entered clinical trials for neuroblastoma patients. Toxic side effects, poor bioavailability and low efficacy of the available MDM2 inhibitors that have entered phase I/II trials drive the development of novel MDM2 inhibitors with an improved risk-benefit profile. We investigated the effect of the novel MDM2 small molecular inhibitor, DS-3032b, on viability, proliferation, senescence, migration, cell cycle arrest and apoptosis in a panel of six neuroblastoma cell lines with different TP53 and MYCN genetic backgrounds, and assessed efficacy in a murine subcutaneous model for high-risk neuroblastoma. Re-analysis of existing expression data from 476 primary neuroblastomas showed that high-level MDM2 expression correlated with poor patient survival. DS-3032b treatment enhanced TP53 target gene expression and induced G1 cell cycle arrest, senescence and apoptosis. CRISPR-mediated MDM2 knockout in neuroblastoma cells mimicked DS-3032b treatment. TP53 signaling was selectively activated by DS-3032b in neuroblastoma cells with wildtype TP53, regardless of the presence of MYCN amplification, but was significantly reduced by TP53 mutations or expression of a dominant-negative TP53 mutant. Oral DS-3032b administration inhibited xenograft tumor growth and prolonged mouse survival. Our in vitro and in vivo data demonstrate that DS-3032b reactivates TP53 signaling even in the presence of MYCN amplification in neuroblastoma cells, to reduce proliferative capacity and cause cytotoxicity. PMID:29416773

Protein - TP Atlas | LSDB Archive [Life Science Database Archive metadata

Lifescience Database Archive (English)

Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...p_atlas_protein.zip File URL: ftp://ftp.biosciencedbc.jp/archive/tp_atlas/LATEST/...story of This Database Site Policy | Contact Us Protein - TP Atlas | LSDB Archive ...

Radiosensitivity and TP 53, EGFR amplification and LOH10 analysis of primary glioma cell cultures

International Nuclear Information System (INIS)

Gerlach, B.; Harder, A.H.; Slotman, B.J.; Sminia, P.; Hulsebos, T.J.M.; Leenstra, S.; Peter Vandertop, W.; Hartmann, K.A.

2002-01-01

Aim: Determination of in-vitro radiosensitivity and genetic alterations of cell cultures derived from human glioma biopsy tissue and established glioma cell lines. Material and Methods: Fresh brain tumor specimens of six patients were processed to early passage cell cultures. In addition the cell lines D 384 and Gli 6 were used. Cell cultures were irradiated with doses from 2 to 10 Gy. Following irradiation, cell survival was determined by clonogenic assay and survival curves were generated. The surviving fractions after 2 Gy (SF2) and 4 Gy (SF4) were used as radiosensitivity parameters. Genetic analysis included determination of the mutational and loss of heterozygosity (LOH) status of TP 53 (exons 5-8), the LOH 10- and epidermal growth factor receptor gene (EGFR) amplification status. Results: The SF2 and SF4 values ranged from 0.54 to 0.88 (mean: 0.70) and from 0.13 to 0.52 (mean: 0.32), respectively. Genetic alterations were found in the Gli 6 cell line and in two primary cell cultures. The genetic profile of Gli 6 showed LOH but no TP 53 mutation, complete LOH 10 and no EGFR amplification. The VU 15 cell culture showed TP 53 mutation but no LOH 10 or EGFR amplification, while VU 24 showed incomplete LOH 10, EGFR amplification and no TP 53 mutation. In the other four cell cultures and D 384 cell line no genetic alterations were diagnosed. Histopathological classification of glioblastoma multiforme and/or genetic alterations resulted in lower radiosensitivity. Conclusion: In this small series of early passage glioma cell cultures low radiosensitivity and alterations in cell regulatory genes were seen. Further testing of biological behavior in larger series of patient-derived material is ongoing. (orig.)

Benzo[a]pyrene, Aflatoxine B1 and Acetaldehyde Mutational Patterns in TP53 Gene Using a Functional Assay: Relevance to Human Cancer Aetiology

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Paget, Vincent; Lechevrel, Mathilde; André, Véronique; Le Goff, Jérémie; Pottier, Didier; Billet, Sylvain; Garçon, Guillaume; Shirali, Pirouz; Sichel, François

2012-01-01

Mutations in the TP53 gene are the most common alterations in human tumours. TP53 mutational patterns have sometimes been linked to carcinogen exposure. In hepatocellular carcinoma, a specific G>T transversion on codon 249 is classically described as a fingerprint of aflatoxin B1 exposure. Likewise G>T transversions in codons 157 and 158 have been related to tobacco exposure in human lung cancers. However, controversies remain about the interpretation of TP53 mutational pattern in tumours as the fingerprint of genotoxin exposure. By using a functional assay, the Functional Analysis of Separated Alleles in Yeast (FASAY), the present study depicts the mutational pattern of TP53 in normal human fibroblasts after in vitro exposure to well-known carcinogens: benzo[a]pyrene, aflatoxin B1 and acetaldehyde. These in vitro patterns of mutations were then compared to those found in human tumours by using the IARC database of TP53 mutations. The results show that the TP53 mutational patterns found in human tumours can be only partly ascribed to genotoxin exposure. A complex interplay between the functional impact of the mutations on p53 phenotype and the cancer natural history may affect these patterns. However, our results strongly support that genotoxins exposure plays a major role in the aetiology of the considered cancers. PMID:22319594

DNA methylation patterns of candidate genes regulated by thymine DNA glycosylase in patients with TP53 germline mutations

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Fortes, F.P. [CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Kuasne, H. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Urologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil); Marchi, F.A. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Programa Inter-Institucional em Bioinformtica, Instituto de Matemtica e Estatstica, Universidade So Paulo, So Paulo, SP (Brazil); Miranda, P.M. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Rogatto, S.R. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Urologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil); Achatz, M.I. [CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Oncogentica, A.C. Camargo Cancer Center, So Paulo, SP (Brazil)

2015-04-28

Li-Fraumeni syndrome (LFS) is a rare, autosomal dominant, hereditary cancer predisposition disorder. In Brazil, the p.R337H TP53 founder mutation causes the variant form of LFS, Li-Fraumeni-like syndrome. The occurrence of cancer and age of disease onset are known to vary, even in patients carrying the same mutation, and several mechanisms such as genetic and epigenetic alterations may be involved in this variability. However, the extent of involvement of such events has not been clarified. It is well established that p53 regulates several pathways, including the thymine DNA glycosylase (TDG) pathway, which regulates the DNA methylation of several genes. This study aimed to identify the DNA methylation pattern of genes potentially related to the TDG pathway (CDKN2A, FOXA1, HOXD8, OCT4, SOX2, and SOX17) in 30 patients with germline TP53mutations, 10 patients with wild-type TP53, and 10 healthy individuals. We also evaluated TDG expression in patients with adrenocortical tumors (ADR) with and without the p.R337H TP53 mutation. Gene methylation patterns of peripheral blood DNA samples assessed by pyrosequencing revealed no significant differences between the three groups. However, increased TDG expression was observed by quantitative reverse transcription PCR in p.R337H carriers with ADR. Considering the rarity of this phenotype and the relevance of these findings, further studies using a larger sample set are necessary to confirm our results.

Molecular Characterization of TP53 Gene in Human Populations Exposed to Low-Dose Ionizing Radiation

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Igor Brasil-Costa

2013-01-01

Full Text Available Ionizing radiation, such as that emitted by uranium, may cause mutations and consequently lead to neoplasia in human cells. The TP53 gene acts to maintain genomic integrity and constitutes an important biomarker of susceptibility. The present study investigated the main alterations observed in exons 4, 5, 6, 7, and 8 of the TP53 gene and adjacent introns in Amazonian populations exposed to radioactivity. Samples were collected from 163 individuals. Occurrence of the following alterations was observed: (i a missense exchange in exon 4 (Arg72Pro; (ii 2 synonymous exchanges, 1 in exon 5 (His179His, and another in exon 6 (Arg213Arg; (iii 4 intronic exchanges, 3 in intron 7 (C → T at position 13.436; C → T at position 13.491; T → G at position 13.511 and 1 in intron 8 (T → G at position 13.958. Alteration of codon 72 was found to be an important risk factor for cancer development (P=0.024; OR=6.48; CI: 1.29–32.64 when adjusted for age and smoking. Thus, TP53 gene may be an important biomarker for carcinogenesis susceptibility in human populations exposed to ionizing radiation.

Mutational pattern of TP53 tumor suppressor gene in human lung cells exposed to air pollution PM{sub 2.5}; Spectre mutationnel de TP53 en reponse a une exposition in vitro a un aerosol atmospherique particulaire PM{sub 2,} {sub 5}

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Billet, Sylvain; Paget, Vincent [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France); Garcon, Guillaume; Verdin, Anthony; Shirali, Pirouz [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); Andre, Veronique; Heutte, Natacha; Sichel, Francois [GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France)

2012-01-15

Environmental exposure to fine airborne particulate matter (PM 2.5) is thought to be responsible for cardiopulmonary diseases, including lung cancer. However, the mechanisms of action potentially involved in PM{sub 2.5} toxicity are not yet fully described. Mutations in the TP53 gene are the most common alterations in human solid tumors. TP53 mutational patterns have sometimes been linked to carcinogen exposure. The purpose of this study was to determine the mutations that alter the functionality of this transcription factor in a model of human epithelial lung cells (A549) exposed to the fine particulate fraction (PM{sub 2.5}) of an atmospheric aerosol sampled under urban and industrial influences. PM{sub 2.5} was collected in Dunkerque City by cascade impaction. Its physicochemical characterization revealed the presence of many inorganic and organic compounds, including some that are known for their toxicity. The search for mutations altering the functionality of the P53 protein was performed 72 h after exposure of A549 cells to PM{sub 2.5} at its lethal concentration at 50% (LC{sub 50}, 118.60 {mu}g/mL = 31.63 {mu}g/cm{sup 2}), using the Functional Analysis of Separated Alleles in Yeast (FASAY). Sixteen mutations altering P53 function were detected after A549 cells exposure to the collected PM{sub 2.5}: eight deletions of one or two nucleotides and eight nucleotide substitutions, mainly transitions A > G and G > A. These mutations are described in the literature as possibly caused by endogenous mechanisms, such as oxidative stress. This kind of alteration can be induced by metal content of the PM{sub 2.5}, as well as by metabolic activation of the organic compounds coated onto its surface. Involvement of oxidative stress in TP53 mutations was confirmed by the detection of an oxidative DNA adduct, 8-hydroxy-2'-deoxyguanosine (8-OHdG), in A549 cells exposed to the collected PM. (authors)

Identical TP53 mutations in pelvic carcinosarcomas and associated serous tubal intraepithelial carcinomas provide evidence of their clonal relationship.

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Ardighieri, Laura; Mori, Luigi; Conzadori, Sara; Bugatti, Mattia; Falchetti, Marcella; Donzelli, Carla Maria; Ravaggi, Antonella; Odicino, Franco E; Facchetti, Fabio

2016-07-01

Pelvic carcinosarcomas (PCSs) are rare aggressive biphasic tumors that localize in the ovary, fallopian tube, or peritoneum and present frequently as bilateral disease. We undertook a morphological, p53 immunohistochemical and TP53 gene mutational analysis study in a single institution cohort of 16 PCSs in order to investigate the nature of bilateral tumors and to shed light on their origin and pathogenesis. Of the 16 patients, 10 presented with bilateral disease, 6 with a carcinosarcoma in both adnexa, and the remaining cases with a carcinosarcoma in one adnexum and a carcinoma in the opposite. The carcinoma component showed high-grade serous features in 13/16 of cases (81 %). In 10 patients (63 %), a serous tubal intraepithelial carcinoma (STIC) was found, in one case bilateral, making a total of 11 STICs. STIC was found only in cases with a carcinoma component with high-grade serous features. All 10 bilateral tumors and all 11 PCS-associated STICs showed a similar p53 immunostaining pattern. At mutation analysis of the TP53 gene, all five bilateral PCS contained an identical mutation in both localizations. Furthermore, a TP53 mutation was found in 8 of 10 STICs, with an identical mutation in the associated PCS. The finding of similar p53 immunostaining in all bilateral cases and identical TP53 mutations in most PCS-associated STIC provides evidence for a clonal relation between these neoplastic lesions, supporting a metastatic nature of bilateral PCS and suggesting that they have an extraovarian origin in a STIC.

BRCA1 and TP53 Gene-Mutations: Family Predisposition and Radioecological Risk of Developing Breast Cancer.

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Apsalikov, Bakytbek; Manambaeva, Zukhra; Ospanov, Erlan; Massabayeva, Meruyert; Zhabagin, Kuantkan; Zhagiparova, Zhanar; Maximov, Vladymir; Voropaeva, Elena; Apsalikov, Kazbek; Belikhina, Tatiana; Abdrahmanov, Ramil; Cherepkova, Elena; Tanatarov, Sayat; Massadykov, Adilzhan; Urazalina, Naylia

2016-01-01

Frequencies of polymorphisms of genes BRCA1 and TP53 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 TP53 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 TP53 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.

Bioinformatics and phylogenetic analysis of human Tp73 gene ...

African Journals Online (AJOL)

The Tp73 gene encoding p73 protein belongs to the Tp53 gene family and it functions in the initiation of cell-cycle arrest or apoptosis and also involves in regulating a series of pathways including breast cancer, neuroblastoma and cholorectal cancer. New discoveries about the control and function of p73 are still in progress ...

Human Papillomavirus 16 Infection and TP53 Mutation: Two Distinct Pathogeneses for Oropharyngeal Squamous Cell Carcinoma in an Eastern Chinese Population

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Wang, Zhen; Xia, Rong-Hui; Ye, Dong-Xia; Li, Jiang

2016-01-01

Objectives To investigate the clinicopathological characteristics, human papillomavirus (HPV) infection, p53 expression, and TP53 mutations in oropharyngeal squamous cell carcinoma (OPSCC) and determine their utility as prognostic predictors in a primarily eastern Chinese population. Methods The HPV infection status was tested via p16INK4A immunohistochemistry and validated using PCR, reverse blot hybridization and in situ hybridization (ISH) in 188 OPSCC samples. p53 expression levels and TP...

Preclinical efficacy of the MDM2 inhibitor RG7112 in MDM2 amplified and TP53 wild-type glioblastomas

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Verreault, Maite; Schmitt, Charlotte; Goldwirt, Lauriane; Pelton, Kristine; Haidar, Samer; Levasseur, Camille; Guehennec, Jeremy; Knoff, David; Labussiere, Marianne; Marie, Yannick; Ligon, Azra H.; Mokhtari, Karima; Hoang-Xuan, Khe; Sanson, Marc; Alexander, Brian M; Wen, Patrick Y.; Delattre, Jean-Yves; Ligon, Keith L.; Idbaih, Ahmed

2016-01-01

Rationale p53 pathway alterations are key molecular events in glioblastoma (GBM). MDM2 inhibitors increase expression and stability of p53 and are presumed to be most efficacious in patients with TP53 wild-type and MDM2-amplified cancers. However, this biomarker hypothesis has not been tested in patients or patient-derived models for GBM. Methods We performed a preclinical evaluation of RG7112 MDM2 inhibitor, across a panel of 36 patient-derived GBM cell lines (PDCLs), each genetically characterized according to their P53 pathway status. We then performed a pharmacokinetic (PK) profiling of RG7112 distribution in mice and evaluated the therapeutic activity of RG7112 in orthotopic and subcutaneous GBM models. Results MDM2-amplified PDCLs were 44 times more sensitive than TP53 mutated lines that showed complete resistance at therapeutically attainable concentrations (avg. IC50 of 0.52 μM vs 21.9 μM). MDM4 amplified PDCLs were highly sensitive but showed intermediate response (avg. IC50 of 1.2 μM), whereas response was heterogeneous in TP53 wild-type PDCLs with normal MDM2/4 levels (avg. IC50 of 7.7 μM). In MDM2-amplified lines, RG7112 restored p53 activity inducing robust p21 expression and apoptosis. PK profiling of RG7112-treated PDCL intracranial xenografts demonstrated that the compound significantly crosses the blood-brain and the blood-tumor barriers. Most importantly, treatment of MDM2-amplified/TP53 wild-type PDCL-derived model (subcutaneous and orthotopic) reduced tumor growth, was cytotoxic, and significantly increased survival. Conclusion These data strongly support development of MDM2 inhibitors for clinical testing in MDM2-amplified GBM patients. Moreover, significant efficacy in a subset of non-MDM2 amplified models suggests that additional markers of response to MDM2 inhibitors must be identified. PMID:26482041

A Chimeric Protein PTEN-L-p53 Enters U251 Cells to Repress Proliferation and Invasion.

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Xiao, Man; An, Yang; Wang, Fengling; Yao, Chao; Zhang, Chu; Xin, Junfang; Duan, Yongjian; Zhao, Xiaofang; Fang, Na; Ji, Shaoping

2018-05-23

PTEN, a well-known tumor suppressor, dephosphorylates PIP3 and inhibits AKT activity. A translational variant of PTEN has been identified and termed PTEN-Long (PTEN-L). The additional 173 amino acids (PTEN-L leader) at the N-terminal constitute a potential signal peptide. Differing from canonical PTEN, PTEN-L is secreted into the extracellular fluid and re-enters recipient cells, playing the similar roles as PTEN in vivo and in vitro. This character confers the PTEN-L a therapeutic ability via directly protein delivering instead of traditional DNA and RNA vector options. In the present study, we employed PTEN-L leader to assemble a fusion protein, PTEN-L-p53, inosculated with the transcriptional regulator TP53, which is another powerful tumor suppressor. We overexpressed PTEN-L-p53 in HEK293T cells and detected it in both the cytoplasm and nucleus. Subsequently, we found that PTEN-L-p53 was secreted outside of the cells and detected in the culture media by immunoblotting. Furthermore, we demonstrated that PTEN-L-p53 freely entered the cells and suppressed the viability of U251cells (p53 R273H , a cell line with p53 R273H-mutation). PTEN-L-p53 is composed of endogenous protein/peptide bearing low immunogenicity, and only the junction region between PTEN-L leader and p53 can act as a new immune epitope. Accordingly, this fusion protein can potentially be used as a therapeutic option for TP53-abnormality cancers. Copyright © 2018. Published by Elsevier Inc.

Frequency of Somatic TP53 Mutations in Combination with Known Pathogenic Mutations in Colon Adenocarcinoma, Non–Small Cell Lung Carcinoma, and Gliomas as Identified by Next-Generation Sequencing

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Zahra Shajani-Yi

2018-03-01

Full Text Available The tumor suppressor gene TP53 is the most frequently mutated gene in human cancer. It encodes p53, a DNA-binding transcription factor that regulates multiple genes involved in DNA repair, metabolism, cell cycle arrest, apoptosis, and senescence. TP53 is associated with human cancer by mutations that lead to a loss of wild-type p53 function as well as mutations that confer alternate oncogenic functions that enable them to promote invasion, metastasis, proliferation, and cell survival. Identifying the discrete TP53 mutations in tumor cells may help direct therapies that are more effective. In this study, we identified the frequency of individual TP53 mutations in patients with colon adenocarcinoma (48%, non–small cell lung carcinoma (NSCLC (36%, and glioma/glioblastoma (28% at our institution using next-generation sequencing. We also identified the occurrence of somatic mutations in numerous actionable genes including BRAF, EGFR, KRAS, IDH1, and PIK3CA that occurred concurrently with these TP53 mutations. Of the 480 tumors examined that contained one or more mutations in the TP53 gene, 219 were colon adenocarcinomas, 215 were NSCLCs, and 46 were gliomas/glioblastomas. Among the patients positive for TP53 mutations diagnosed with colon adenocarcinoma, 50% also showed at least one mutation in pathogenic genes of which 14% were BRAF, 33% were KRAS, and 3% were NRAS. Forty-seven percent of NSCLC patients harboring TP53 mutations also had a mutation in at least one actionable pathogenic variant with the following frequencies: BRAF: 4%, EGFR: 10%, KRAS: 28%, and PIK3CA: 4%. Fifty-two percent of patients diagnosed with glioma/glioblastoma with a positive TP53 mutation had at least one concurrent mutation in a known pathogenic gene of which 9% were CDKN2A, 41% were IDH1, and 11% were PIK3CA.

TP53 mutations in serous tubal intraepithelial carcinoma and concurrent pelvic high-grade serous carcinoma—evidence supporting the clonal relationship of the two lesions

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Kuhn, Elisabetta; Kurman, Robert J; Vang, Russell; Sehdev, Ann Smith; Han, Guangming; Soslow, Robert; Wang, Tian-Li; Shih, Ie-Ming

2016-01-01

Serous tubal intraepithelial carcinomas (STICs) have been proposed to be the most likely precursor of ovarian, tubal and ‘primary peritoneal’ (pelvic) high-grade serous carcinoma (HGSC). As somatic mutation of TP53 is the most common molecular genetic change of ovarian HGSC, occurring in more than 95% of cases, we undertook a mutational analysis of 29 pelvic HGSCs that had concurrent STICs to demonstrate the clonal relationship of STICs and HGSCs. In addition, we correlated the mutational data with p53 immunostaining to determine the role of p53 immunoreactivity as a surrogate for TP53 mutations in histological diagnosis. Somatic TP53 mutations were detected in all 29 HGSCs analysed and the identical mutations were detected in 27 of 29 pairs of STICs and concurrent HGSCs. Missense mutations were observed in 61% of STICs and frameshift/splicing junction/nonsense mutations in 39%. Interestingly, there were two HGSCs with two distinctly different TP53 mutations each, but only one of the mutations was detected in the concurrent STICs. Missense mutations were associated with intense and diffuse (≥ 60%) p53 nuclear immunoreactivity, while most of the null mutations were associated with complete loss of p53 staining (p STIC and pelvic HGSC and demonstrate the utility of p53 immunostaining as a surrogate for TP53 mutation in the histological diagnosis of STIC. In this regard, it is important to appreciate the significance of different staining patterns. Specifically, strong diffuse staining correlates with a missense mutation, whereas complete absence of staining correlates with null mutations. PMID:21990067

Association of polymorphism in TP53 gene with susceptibility and radiation sensitivity of non-small-cell-lung cancer in Chinese population

International Nuclear Information System (INIS)

Shao Guoguang; Liu Linlin; Xu Chuanjie

2005-01-01

Objective: To study the association of polymorphism in TP53 gene with the susceptibility and radiation sensitivity of non-small-cell-lung cancer (NSCLC) of the population in the North of China. Methods: Using RFLP-PCR assays, TP53 genotypes were detected by amplifying DNA fragments with sequence specific primers and digested by FnuD II enzyme in 88 patients with NSCLC as well as 112 healthy controls. Results: The C/C allele frequency was significantly higher in NSCLC patients than that in the healthy controls (χ 2 =5.65, P=0.017). The C/C genotype frequency was significantly higher in NSCLC patients than that of the healthy controls (χ 2 =9.33, P=0.0023). The risk of C/C homozygotes in NSCLC patients was about 2.7 times against G/G homozygotes with odds ratio of 2.43(95% CI=1.32-4.51). Conclusion: In the population in the North of China, TP53 C/C genotype is closely associated with the susceptibility of NSCLC. There is no significant relationship between the polymorphism in TP53 gene and radiation sensitivity in NSCLC. (authors)

Diagnostic value of recombinant Tp0821 protein in serodiagnosis for syphilis.

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Xie, Y; Xu, M; Wang, C; Xiao, J; Xiao, Y; Jiang, C; You, X; Zhao, F; Zeng, T; Liu, S; Kuang, X; Wu, Y

2016-04-01

Syphilis is a multistage sexually transmitted disease that remains a serious public health concern worldwide. The coexistence of Treponema pallidum with other closely related members of spirochaeta, such as Leptospira spp. and Borrelia burgdorferi, has complicated the serodiagnosis due to cross-reactive antigens. In this study, recombinant Tp0821 protein was expressed in Escherichia coli and purified by metal affinity chromatography. Then enzyme-linked immunosorbent assays (ELISAs) based on Tp0821 for the detection of specific antibodies were established. The relative positive rates of the IgM ELISA and the IgG ELISA were found to be 91·0 and 98·3%, respectively, when screening 578 syphilis specimens. The specificities were 94·3 and 100%, respectively, when cross-checking with serum samples obtained from 30 patients with Lyme disease, five patients with leptospirosis, and 52 uninfected controls. In addition, relative positive rates and specificities of Tp0821 for human sera were all 100% in Western blotting. When compared to the syphilis diagnostic tests commonly used in clinical settings, we found that the results of Tp0821-based ELISAs correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the chemiluminescent immunoassay (CIA). Thus, these findings identify Tp0821 as a novel serodiagnostic candidate for syphilis. In this study, we expressed and purified the Treponema pallidum protein Tp0821 and developed Tp0821-based enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies. The serodiagnostic performance of the recombinant protein was then evaluated. When compared to the results of syphilis diagnostic tests commonly used in clinical settings, we found that the reactivities of syphilitic sera with the recombinant antigen correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the

Src kinases in chondrosarcoma chemoresistance and migration: dasatinib sensitises to doxorubicin in TP53 mutant cells

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van Oosterwijk, J G; van Ruler, M A J H; Briaire-de Bruijn, I H; Herpers, B; Gelderblom, H; van de Water, B; Bovée, J V M G

2013-01-01

Background: Chondrosarcomas are malignant cartilage-forming tumours of bone. Because of their resistance to conventional chemotherapy and radiotherapy, currently no treatment strategies exist for unresectable and metastatic chondrosarcoma. Previously, PI3K/AKT/GSK3β and Src kinase pathways were shown to be activated in chondrosarcoma cell lines. Our aim was to investigate the role of these kinases in chemoresistance and migration in chondrosarcoma in relation to TP53 mutation status. Methods: We used five conventional and three dedifferentiated chondrosarcoma cell lines and investigated the effect of PI3K/AKT/GSK3β pathway inhibition (enzastaurin) and Src pathway inhibition (dasatinib) in chemoresistance using WST assay and live cell imaging with AnnexinV staining. Immunohistochemistry on tissue microarrays (TMAs) containing 157 cartilaginous tumours was performed for Src family members. Migration assays were performed with the RTCA xCelligence System. Results: Src inhibition was found to overcome chemoresistance, to induce apoptosis and to inhibit migration. Cell lines with TP53 mutations responded better to combination therapy than wild-type cell lines (P=0.002). Tissue microarray immunohistochemistry confirmed active Src (pSrc) signalling, with Fyn being most abundantly expressed (76.1%). Conclusion: These results strongly indicate Src family kinases, in particular Fyn, as a potential target for the treatment of inoperable and metastatic chondrosarcomas, and to sensitise for doxorubicin especially in the presence of TP53 mutations. PMID:23922104

Unambiguous detection of multiple TP53 gene mutations in AAN-associated urothelial cancer in Belgium using laser capture microdissection.

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Selda Aydin

Full Text Available In the Balkan and Taiwan, the relationship between exposure to aristolochic acid and risk of urothelial neoplasms was inferred from the A>T genetic hallmark in TP53 gene from malignant cells. This study aimed to characterize the TP53 mutational spectrum in urothelial cancers consecutive to Aristolochic Acid Nephropathy in Belgium. Serial frozen tumor sections from female patients (n=5 exposed to aristolochic acid during weight-loss regimen were alternatively used either for p53 immunostaining or laser microdissection. Tissue areas with at least 60% p53-positive nuclei were selected for microdissecting sections according to p53-positive matching areas. All areas appeared to be carcinoma in situ. After DNA extraction, mutations in the TP53 hot spot region (exons 5-8 were identified using nested-PCR and sequencing. False-negative controls consisted in microdissecting fresh-frozen tumor tissues both from a patient with a Li-Fraumeni syndrome who carried a p53 constitutional mutation, and from KRas mutated adenocarcinomas. To rule out false-positive results potentially generated by microdissection and nested-PCR, a phenacetin-associated urothelial carcinoma and normal fresh ureteral tissues (n=4 were processed with high laser power. No unexpected results being identified, molecular analysis was pursued on malignant tissues, showing at least one mutation in all (six different mutations in two patients, with 13/16 exonic (nonsense, 2; missense, 11 and 3/16 intronic (one splice site mutations. They were distributed as transitions (n=7 or transversions (n=9, with an equal prevalence of A>T and G>T (3/16 each. While current results are in line with A>T prevalence previously reported in Balkan and Taiwan studies, they also demonstrate that multiple mutations in the TP53 hot spot region and a high frequency of G>T transversion appear as a complementary signature reflecting the toxicity of a cumulative dose of aristolochic acid ingested over a short period

Human Papillomavirus 16 Infection and TP53 Mutation: Two Distinct Pathogeneses for Oropharyngeal Squamous Cell Carcinoma in an Eastern Chinese Population.

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Zhen Wang

Full Text Available To investigate the clinicopathological characteristics, human papillomavirus (HPV infection, p53 expression, and TP53 mutations in oropharyngeal squamous cell carcinoma (OPSCC and determine their utility as prognostic predictors in a primarily eastern Chinese population.The HPV infection status was tested via p16INK4A immunohistochemistry and validated using PCR, reverse blot hybridization and in situ hybridization (ISH in 188 OPSCC samples. p53 expression levels and TP53 gene mutations were assessed through immunohistochemistry and sequencing, respectively. Clinicopathological characteristics and follow-up information were collected. Overall survival was estimated using the Log-rank test.Overall, 22 of the 188 OPSCC samples were associated with HPV infection. HPV16 was identified in all 22 samples, whereas no samples were positive for HPV18. All 22 HPV-associated OPSCC samples were p53 negative and lacked TP53 mutations. HPV16 positivity, female patients, non-smokers, and patients with histological grade I and stage N0 diseases showed better overall survival (p = 0.009, 0.003, 0.048, 0.009, and 0.004, respectively. No significant differences in overall survival between smoking and non-smoking patients were observed in the HPV-associated OPSCC group. Patients without mutations in TP53 exons 5-8 had better prognoses (p = 0.031 among the 43 sequenced specimens. Multivariate analysis indicated that HPV16 infection status (p = 0.011, histological grade (p = 0.017, and N stage (p = 0.019 were independent prognostic factors for patients with OPSCC.Distinct from the situation in Europe and America, for the patients with OPSCC in this study, HPV16 infection was relatively low, although it was still the most important independent prognostic predictor for the disease. In addition to the high smoking and drinking rate in this population, HPV16 infection and TP53 dysfunction appear to be two distinct pathogens for OPSCC patients in the eastern Chinese

Human Papillomavirus 16 Infection and TP53 Mutation: Two Distinct Pathogeneses for Oropharyngeal Squamous Cell Carcinoma in an Eastern Chinese Population.

Science.gov (United States)

Wang, Zhen; Xia, Rong-Hui; Ye, Dong-Xia; Li, Jiang

2016-01-01

To investigate the clinicopathological characteristics, human papillomavirus (HPV) infection, p53 expression, and TP53 mutations in oropharyngeal squamous cell carcinoma (OPSCC) and determine their utility as prognostic predictors in a primarily eastern Chinese population. The HPV infection status was tested via p16INK4A immunohistochemistry and validated using PCR, reverse blot hybridization and in situ hybridization (ISH) in 188 OPSCC samples. p53 expression levels and TP53 gene mutations were assessed through immunohistochemistry and sequencing, respectively. Clinicopathological characteristics and follow-up information were collected. Overall survival was estimated using the Log-rank test. Overall, 22 of the 188 OPSCC samples were associated with HPV infection. HPV16 was identified in all 22 samples, whereas no samples were positive for HPV18. All 22 HPV-associated OPSCC samples were p53 negative and lacked TP53 mutations. HPV16 positivity, female patients, non-smokers, and patients with histological grade I and stage N0 diseases showed better overall survival (p = 0.009, 0.003, 0.048, 0.009, and 0.004, respectively). No significant differences in overall survival between smoking and non-smoking patients were observed in the HPV-associated OPSCC group. Patients without mutations in TP53 exons 5-8 had better prognoses (p = 0.031) among the 43 sequenced specimens. Multivariate analysis indicated that HPV16 infection status (p = 0.011), histological grade (p = 0.017), and N stage (p = 0.019) were independent prognostic factors for patients with OPSCC. Distinct from the situation in Europe and America, for the patients with OPSCC in this study, HPV16 infection was relatively low, although it was still the most important independent prognostic predictor for the disease. In addition to the high smoking and drinking rate in this population, HPV16 infection and TP53 dysfunction appear to be two distinct pathogens for OPSCC patients in the eastern Chinese population.

Combined human papillomavirus typing and TP53 mutation analysis in distinguishing second primary tumors from lung metastases in patients with head and neck squamous cell carcinoma.

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Daher, Tamas; Tur, Mehmet Kemal; Brobeil, Alexander; Etschmann, Benjamin; Witte, Biruta; Engenhart-Cabillic, Rita; Krombach, Gabriele; Blau, Wolfgang; Grimminger, Friedrich; Seeger, Werner; Klussmann, Jens Peter; Bräuninger, Andreas; Gattenlöhner, Stefan

2018-06-01

In head and neck squamous cell carcinoma (HNSCC), the occurrence of concurrent lung malignancies poses a significant diagnostic challenge because metastatic HNSCC is difficult to discern from second primary lung squamous cell carcinoma (SCC). However, this differentiation is crucial because the recommended treatments for metastatic HNSCC and second primary lung SCC differ profoundly. We analyzed the origin of lung tumors in 32 patients with HNSCC using human papillomavirus (HPV) typing and targeted next generation sequencing of all coding exons of tumor protein 53 (TP53). Lung tumors were clearly identified as HNSCC metastases or second primary tumors in 29 patients, thus revealing that 16 patients had received incorrect diagnoses based on clinical and morphological data alone. The HPV typing and mutation analysis of all TP53 coding exons is a valuable diagnostic tool in patients with HNSCC and concurrent lung SCC, which can help to ensure that patients receive the most suitable treatment. © 2018 Wiley Periodicals, Inc.

Human TP53 polymorphism (rs1042522) modelled in mouse does not affect glucose metabolism and body composition.

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Reiling, Erwin; Speksnijder, Ewoud N; Pronk, Amanda C M; van den Berg, Sjoerd A A; Neggers, Silvia J W; Rietbroek, Ilma; van Steeg, Harry; Dollé, Martijn E T

2014-02-13

Variation in TP53 has been associated with cancer. The pro-allele of a TP53 polymorphism in codon 72 (rs1042522) has been associated with longevity. Recently, we showed that the same allele might be involved in preservation of glucose metabolism, body composition and blood pressure during ageing. Here, we assessed glucose tolerance and body composition in mice carrying the human polymorphism. Our data do not support the previous findings in humans, suggesting that this polymorphism does not play a major role in development of glucose metabolism and body composition during ageing. Alternatively, the mouse model may not be suitable to validate these rs1042522-associated traits up to the age tested.

TP53 mutations in serous tubal intraepithelial carcinoma and concurrent pelvic high-grade serous carcinoma--evidence supporting the clonal relationship of the two lesions.

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Kuhn, Elisabetta; Kurman, Robert J; Vang, Russell; Sehdev, Ann Smith; Han, Guangming; Soslow, Robert; Wang, Tian-Li; Shih, Ie-Ming

2012-02-01

Serous tubal intraepithelial carcinomas (STICs) have been proposed to be the most likely precursor of ovarian, tubal and 'primary peritoneal' (pelvic) high-grade serous carcinoma (HGSC). As somatic mutation of TP53 is the most common molecular genetic change of ovarian HGSC, occurring in more than 95% of cases, we undertook a mutational analysis of 29 pelvic HGSCs that had concurrent STICs to demonstrate the clonal relationship of STICs and HGSCs. In addition, we correlated the mutational data with p53 immunostaining to determine the role of p53 immunoreactivity as a surrogate for TP53 mutations in histological diagnosis. Somatic TP53 mutations were detected in all 29 HGSCs analysed and the identical mutations were detected in 27 of 29 pairs of STICs and concurrent HGSCs. Missense mutations were observed in 61% of STICs and frameshift/splicing junction/nonsense mutations in 39%. Interestingly, there were two HGSCs with two distinctly different TP53 mutations each, but only one of the mutations was detected in the concurrent STICs. Missense mutations were associated with intense and diffuse (≥ 60%) p53 nuclear immunoreactivity, while most of the null mutations were associated with complete loss of p53 staining (p STIC and pelvic HGSC and demonstrate the utility of p53 immunostaining as a surrogate for TP53 mutation in the histological diagnosis of STIC. In this regard, it is important to appreciate the significance of different staining patterns. Specifically, strong diffuse staining correlates with a missense mutation, whereas complete absence of staining correlates with null mutations. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Contribution of the TP53 R337H mutation to the cancer burden in southern Brazil: Insights from the study of 55 families of children with adrenocortical tumors.

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Mastellaro, Maria J; Seidinger, Ana L; Kang, Guolian; Abrahão, Renata; Miranda, Eliana C M; Pounds, Stanley B; Cardinalli, Izilda A; Aguiar, Simone S; Figueiredo, Bonald C; Rodriguez-Galindo, Carlos; Brandalise, Silvia R; Yunes, José A; Barros-Filho, Antônio de A; Ribeiro, Raul C

2017-08-15

The tumor protein p53 (TP53) arginine-to-histidine mutation at codon 337 (R337H) predisposes children to adrenocortical tumors (ACTs) and, rarely, to other childhood tumors, but its impact on adult cancer remains undetermined. The objective of this study was to investigate the frequency and types of cancer in relatives of children with ACT who carry the TP53 R337H mutation. TP53 R337H testing was offered to relatives of probands with ACT. The parental lineage segregating the R337H mutation was identified in all families. The frequency and distribution of cancer types were compared according to R337H status. The authors' data also were compared with those publicly available for children with TP53 mutations other than R337H. The mean and median follow-up times for the probands with ACT were 11.2 years and 9.7 years (range, 3-32 years), respectively. During this time, cancer was diagnosed in 12 of 81 first-degree relatives (14.8%) carrying the R337H mutation but in only 1 of 94 noncarriers (1.1%; P = .0022). At age 45 years, the cumulative risk of cancer was 21% (95% confidence interval, 5%-33%) in carriers and 2% (95% confidence interval, 0%-4%) in noncarriers (P = .008). The frequency of cancer was higher in the R337H segregating lineages than in the nonsegregating lineages (249 of 1410 vs 66 of 984 individuals; P cancer were the most common types. TP53 R337H carriers have a lifelong predisposition to cancer with a bimodal age distribution: 1 peak, represented by ACT, occurs in the first decade of life, and another peak of diverse cancer types occurs in the fifth decade. The current findings have implications for genetic counseling and surveillance of R337H carriers. Cancer 2017;123:3150-58. © 2017 American Cancer Society. © 2017 American Cancer Society.

Major prognostic value of complex karyotype in addition to TP53 and IGHV mutational status in first-line chronic lymphocytic leukemia.

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Le Bris, Yannick; Struski, Stéphanie; Guièze, Romain; Rouvellat, Caroline; Prade, Naïs; Troussard, Xavier; Tournilhac, Olivier; Béné, Marie C; Delabesse, Eric; Ysebaert, Loïc

2017-12-01

Chronic lymphocytic leukemia (CLL) is a lymphoproliferative disorder of remarkable heterogeneity as demonstrated by cytogenetics and molecular analyses. Complex karyotype (CK), TP53 deletions and/or mutations (TP53 disruption), IGVH mutational status, and, more recently, recurrent somatic mutations have been identified as prognostic markers in CLL. On a cohort of 110 patients with CLL treated with first-line fludarabin, cyclophosphamide, and rituximab treatment compared with 33 untreated (watch and wait) patients with CLL, we report more frequent complex karyotypes (34 vs 15%; P = .05), unmutated IGHV (70 vs 21%; P < .0001), ATM deletion (25 vs 6%, P = .02), and NOTCH mutation (3 vs 17%, P = .04). Among treated patients, 39 relapsed during the follow-up period. These patients were characterized before treatment by a higher incidence of trisomy 12 (38 vs 11%, P < .001) and TP53 disruption (31 vs 4%, P = .0002). A significantly shorter 5-year overall survival was found for treated patients with CK (72.4 vs 85.8%; P = .007), unmutated IGHV (70 vs 100%; P = .04), or TP53 disruption (55.7 vs 82.7%; P < .0001). Three risk groups were defined based on the status of TP53 disruption or unmutated IGVH, which differed significantly in terms of 5-year overall survival. Moreover, the presence of CK impacted pejoratively 5-year overall survival and progression-free survival in all these 3 groups. Conventional karyotyping therefore appears to be of value, CK being an additional factor, undetectable in classical FISH, in patients with CLL at the stage when therapy becomes required. Copyright © 2016 John Wiley & Sons, Ltd.

Importance of TP53 and RB in the repair of potentially lethal damage and induction of color junctions after exposure to ionizing radiation

NARCIS (Netherlands)

Franken, N. A. P.; van Bree, C.; ten Cate, R.; van Oven, C. H.; Haveman, J.

2002-01-01

Repair of potentially lethal damage (PLD) was investigated in cells with functional G(1)-phase arrest with wild-type TP53 and wild-type RB and in cells in which G(1)-phase arrest was abrogated by inactivation of TP53 or RB. Confluent cultures of cells were plated for clonogenic survival assay either

Meta-analysis of association between the TP53 Arg72Pro polymorphism and risk of endometriosis based on case-control studies.

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Yan, Yulan; Wu, Renzheng; Li, Shaojing; He, Jinlong

2015-06-01

In the light of the relationship between the TP53 Arg72Pro (rs1042522) polymorphism and the risk of endometriosis remains inclusive or controversial. For better understanding of the effect of TP53 Arg72Pro polymorphism on endometriosis risk, we performed a meta-analysis. The relevant studies were identified through a search of PubMed, Web of Science, EMBASE, Ovid, Springer, China National Knowledge Infrastructure (CNKI), cqvip, Wanfang database, and Chinese Biomedical Literature (CBM) databases up to December, 2014. The association between the TP53 Arg72Pro polymorphism and endometriosis risk was pooled by conducted by odds ratios and 95% confidence intervals. A total of fifteen case-control studies with 2683 cases and 3335 controls were eventually identified. There was significant association between Arg72Pro polymorphism and endometriosis risk in all of the five models in overall populations (C vs. G: OR=1.32, 95%CI=1.14-1.53, p=0.00; CC vs. GG: OR=1.80, 95%CI=1.28-2.53, p=0.001; GC vs. GG: OR=1.52, 95%CI=1.22-1.88, p=0.00; CC vs. OR=1.32, 95%CI=1.05-1.66, p=0.016; CC/GC vs. GG: OR=1.59, 95%CI=1.26-2.00, p=0.00). In the sub-group analysis according to ethnicity, the results suggested that TP53 Arg72Pro polymorphism was not associated with endometriosis risk in Caucasians. However, the significant association was found in Asians and Mixed race (MIX) under the five models. The results of this meta-analysis suggest that the TP53 Arg72Pro polymorphism can increase the risk of endometriosis, especially among Asians and MIX populations. Considering the limited sample size and ethnicities included in the meta-analysis, further larger scaled and well-designed studies are needed to confirm our results. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

p53 protein expression in corneal squamous cell carcinomas of dogs

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Lucas Bahdour Cossi

2015-06-01

Full Text Available Ocular tumors play an increasing concern in veterinary ophthalmology. Corneal squamous cell carcinoma is unfrequent in dogs, and by this way it has little studies. Studies that investigated the carcinogenesis mechanisms wich could help to the development of ocular squamous cell carcinoma (SCC in dog are rare. The aim of this work was to identify by immunohistochemical techniques, the p53 protein expression in the spontaneous dog corneal SCC. For this work, were used five cases of corneal SCC and one case of actinic keratitis. The sections were obtained from paraffin-wax blocks and submitted to histopathological and immunohistochemical analysis. All the six samples showed immunolabeling to cytokeratin and p53 protein. These results support the conclusions that the immunoreactivity of p53 protein by immunohistochemistry is present in canine corneal SCC suppporting its role in carcinogenesis of this tumor, but not provides prognostic indicators in cases of SCC corneal in dog; and can be a association of exposure to solar radiation with the possible mutation of the TP53 gene.

TP53 germline mutation testing in 180 families suspected of Li-Fraumeni syndrome: mutation detection rate and relative frequency of cancers in different familial phenotypes

NARCIS (Netherlands)

Ruijs, M.W.G.; Verhoef, S.; Rookus, M.A.; Pruntel, R.; van der Hout, A.H.; Hogervorst, F.B.L.; Kluijt, I.; Sijmons, R.H.; Aalfs, C.M.; Wagner, A.; Ausems, M.G.E.M.; Hoogerbrugge, N.; van Asperen, C.J.; Gómez García, E.B.; Meijers-Heijboer, H.; ten Kate, L.P.; Menko, F.H.; van 't Veer, L.J.

2010-01-01

Background Li-Fraumeni syndrome (LFS) is a rare autosomal dominant cancer predisposition syndrome. Most families fulfilling the classical diagnostic criteria harbour TP53 germline mutations. However, TP53 germline mutations may also occur in less obvious phenotypes. As a result, different criteria

Association of the germline TP53 R72P and MDM2 SNP309 variants with breast cancer survival in specific breast tumor subgroups

NARCIS (Netherlands)

van den Broek, Alexandra J.; Broeks, Annegien; Horlings, Hugo M.; Canisius, Sander V. M.; Braaf, Linde M.; Langerød, Anita; van't Veer, Laura J.; Schmidt, Marjanka K.

2011-01-01

The tumor suppressor gene TP53 and its regulator MDM2 are both important players in the DNA-damage repair "TP53 response pathway". Common germline polymorphisms in these genes may affect outcome in patients with tumors characterized by additional somatic changes in the same or a related pathway. To

TP53 suppression promotes erythropoiesis in del(5q) MDS, suggesting a targeted therapeutic strategy in lenalidomide-resistant patients

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Caceres, Gisela; McGraw, Kathy; Yip, Bon Ham; Pellagatti, Andrea; Johnson, Joseph; Zhang, Ling; Liu, Kenian; Zhang, Lan Min; Fulp, William J.; Lee, Ji-Hyun; Al Ali, Najla H.; Basiorka, Ashley; Smith, Larry J.; Daugherty, F. Joseph; Littleton, Neil; Wells, Richard A.; Sokol, Lubomir; Wei, Sheng; Komrokji, Rami S.; Boultwood, Jacqueline; List, Alan F.

2013-01-01

Stabilization of p53 in erythroid precursors in response to nucleosomal stress underlies the hypoplastic anemia in myelodysplastic syndromes (MDS) with chromosome 5q deletion [del(5q)]. We investigated whether cenersen, a clinically active 20-mer antisense oligonucleotide complementary to TP53 exon10, could suppress p53 expression and restore erythropoiesis in del(5q) MDS. Cenersen treatment of ribosomal protein S-14-deficient erythroblasts significantly reduced cellular p53 and p53-up-regulated modulator of apoptosis expression compared with controls, accompanied by a significant reduction in apoptosis and increased cell proliferation. In a two-stage erythroid differentiation assay, cenersen significantly suppressed nuclear p53 in bone marrow CD34+ cells isolated from patients with del(5q) MDS, whereas erythroid burst recovery increased proportionally to the magnitude of p53 suppression without evidence of del(5q) clonal suppression (r = −0.6; P = 0.005). To explore the effect of p53 suppression on erythropoiesis in vivo, dexamethasone, a glucocorticoid receptor-dependent p53 antagonist, was added to lenalidomide treatment in eight lower-risk, transfusion-dependent, del(5q) MDS patients with acquired drug resistance. Transfusion independence was restored in five patients accompanied by expansion of erythroid precursors and decreased cellular p53 expression. We conclude that targeted suppression of p53 could support effective erythropoiesis in lenalidomide-resistant del(5q) MDS. PMID:24043769

TP53, STK11 and EGFR Mutations Predict Tumor Immune Profile and the Response to anti-PD-1 in Lung Adenocarcinoma.

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Biton, Jerome; Mansuet-Lupo, Audrey; Pécuchet, Nicolas; Alifano, Marco; Ouakrim, Hanane; Arrondeau, Jennifer; Boudou-Rouquette, Pascaline; Goldwasser, Francois; Leroy, Karen; Goc, Jeremy; Wislez, Marie; Germain, Claire; Laurent-Puig, Pierre; Dieu-Nosjean, Marie-Caroline; Cremer, Isabelle; Herbst, Ronald; Blons, Hélène F; Damotte, Diane

2018-05-15

By unlocking anti-tumor immunity, antibodies targeting programmed cell death 1 (PD-1) exhibit impressive clinical results in non-small cell lung cancer, underlining the strong interactions between tumor and immune cells. However, factors that can robustly predict long-lasting responses are still needed. We performed in depth immune profiling of lung adenocarcinoma using an integrative analysis based on immunohistochemistry, flow-cytometry and transcriptomic data. Tumor mutational status was investigated using next-generation sequencing. The response to PD-1 blockers was analyzed from a prospective cohort according to tumor mutational profiles and to PD-L1 expression, and a public clinical database was used to validate the results obtained. We showed that distinct combinations of STK11 , EGFR and TP53 mutations, were major determinants of the tumor immune profile (TIP) and of the expression of PD-L1 by malignant cells. Indeed, the presence of TP53 mutations without co-occurring STK11 or EGFR alterations ( TP53 -mut/ STK11 - EGFR -WT), independently of KRAS mutations, identified the group of tumors with the highest CD8 T cell density and PD-L1 expression. In this tumor subtype, pathways related to T cell chemotaxis, immune cell cytotoxicity, and antigen processing were up-regulated. Finally, a prolonged progression-free survival (PFS: HR=0.32; 95% CI, 0.16-0.63, p <0.001) was observed in anti-PD-1 treated patients harboring TP53 -mut/ STK11 - EGFR -WT tumors. This clinical benefit was even more remarkable in patients with associated strong PD-L1 expression. Our study reveals that different combinations of TP53 , EGFR and STK11 mutations , together with PD-L1 expression by tumor cells, represent robust parameters to identify best responders to PD-1 blockade. Copyright ©2018, American Association for Cancer Research.

Complex Biological Systems Analysis of Cell Cycling Models in Carcinogenesis: I. The essential roles of modifications in the c-Myc, TP53/p53, p27 and hTERT modules in Cancer Initiation and Progression

CERN Document Server

Prisecaru, V I

2004-01-01

A new approach to the integration of results from a modular, complex biological systems analysis of nonlinear dynamics in cell cycling network transformations that are leading to carcinogenesis is proposed. Carcinogenesis is a complex process that involves dynamically inter-connected biomolecules in the intercellular, membrane, cytosolic, nuclear and nucleolar compartments that form numerous inter-related pathways referred to as networks. One such network module contains the cell cyclins whose functions are essential to cell cycling and division. Cyclins are proteins that also link to several critical pro-apoptotic and other cell cycling/division components, such as: c-Myc, p27, the tumor suppressor gene TP53 and its product-- the p53 protein with key roles in controlling DNA repair, inducing apoptosis and activating p21 (which can depress cell cyclins if activated), mdm2(with its biosynthesis activated by p53 and also, in its turn, inhibiting p53), p21, the Thomsen-Friedenreich antigen(T- antigen),Rb,Bax, Ba...

TP53 mutations in ovarian carcinomas from sporadic cases and carriers of two distinct BRCA1 founder mutations; relation to age at diagnosis and survival

International Nuclear Information System (INIS)

Kringen, Pedro; Wang, Yun; Dumeaux, Vanessa; Kristensen, Gunnar; Borresen-Dale, Anne-Lise; Dorum, Anne

2005-01-01

Ovarian carcinomas from 30 BRCA1 germ-line carriers of two distinct high penetrant founder mutations, 20 carrying the 1675delA and 10 the 1135insA, and 100 sporadic cases were characterized for somatic mutations in the TP53 gene. We analyzed differences in relation to BRCA1 germline status, TP53 status, survival and age at diagnosis, as previous studies have not been conclusive. DNA was extracted from paraffin embedded formalin fixed tissues for the familial cases, and from fresh frozen specimen from the sporadic cases. All cases were treated at our hospital according to protocol. Mutation analyses of exon 2 – 11 were performed using TTGE, followed by sequencing. Survival rates for BRCA1-familial cases with TP53 mutations were not significantly lower than for familial cases without TP53 mutations (p = 0.25, RR = 1.64, 95% CI [0.71–3.78]). Median age at diagnosis for sporadic (59 years) and familial (49 years) cases differed significantly (p < 0.001) with or without TP53 mutations. Age at diagnosis between the two types of familial carriers were not significantly different, with median age of 47 for 1675delA and 52.5 for 1135insA carriers (p = 0.245). For cases ≥50 years at diagnosis, a trend toward longer survival for sporadic over familial cases was observed (p = 0.08). The opposite trend was observed for cases <50 years at diagnosis. There do not seem to be a protective advantage for familial BRCA1 carriers without TP53 mutations over familial cases with TP53 mutations. However, there seem to be a trend towards initial advantage in survival for familial cases compared to sporadic cases diagnosed before the age of 50 both with and without TP53 mutations. However, this trend diminishes over time and for cases diagnosed ≥50 years the sporadic cases show a trend towards an advantage in survival over familial cases. Although this data set is small, if confirmed, this may be a link in the evidence that the differences in ovarian cancer survival reported, are

EBV-Negative Monomorphic B-Cell Posttransplant Lymphoproliferative Disorder with Marked Morphologic Pleomorphism and Pathogenic Mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53.

Science.gov (United States)

Bogusz, Agata M

2017-01-01

Posttransplant lymphoproliferative disorders (PTLDs) are a diverse group of lymphoid or plasmacytic proliferations frequently driven by Epstein-Barr virus (EBV). EBV-negative PTLDs appear to represent a distinct entity. This report describes an unusual case of a 33-year-old woman that developed a monomorphic EBV-negative PTLD consistent with diffuse large B-cell lymphoma (DLBCL) 13 years after heart-lung transplant. Histological examination revealed marked pleomorphism of the malignant cells including nodular areas reminiscent of classical Hodgkin lymphoma (cHL) with abundant large, bizarre Hodgkin-like cells. By immunostaining, the malignant cells were immunoreactive for CD45, CD20, CD79a, PAX5, BCL6, MUM1, and p53 and negative for CD15, CD30, latent membrane protein 1 (LMP1), and EBV-encoded RNA (EBER). Flow cytometry demonstrated lambda light chain restricted CD5 and CD10 negative B-cells. Fluorescence in situ hybridization studies (FISH) were negative for cMYC , BCL2, and BCL6 rearrangements but showed deletion of TP53 and monosomy of chromosome 17. Next-generation sequencing studies (NGS) revealed numerous genetic alterations including 6 pathogenic mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53 (x2) genes and 30 variants of unknown significance (VOUS) in ABL1, ASXL1, ATM, BCOR, BCORL1, BRNIP3, CDH2, CDKN2A, DNMT3A, ETV6, EZH2, FBXW7, KIT, NF1, RUNX1, SETPB1, SF1, SMC1A, STAG2, TET2, TP53, and U2AF2.

EBV-Negative Monomorphic B-Cell Posttransplant Lymphoproliferative Disorder with Marked Morphologic Pleomorphism and Pathogenic Mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53

Directory of Open Access Journals (Sweden)

Agata M. Bogusz

2017-01-01

Full Text Available Posttransplant lymphoproliferative disorders (PTLDs are a diverse group of lymphoid or plasmacytic proliferations frequently driven by Epstein-Barr virus (EBV. EBV-negative PTLDs appear to represent a distinct entity. This report describes an unusual case of a 33-year-old woman that developed a monomorphic EBV-negative PTLD consistent with diffuse large B-cell lymphoma (DLBCL 13 years after heart-lung transplant. Histological examination revealed marked pleomorphism of the malignant cells including nodular areas reminiscent of classical Hodgkin lymphoma (cHL with abundant large, bizarre Hodgkin-like cells. By immunostaining, the malignant cells were immunoreactive for CD45, CD20, CD79a, PAX5, BCL6, MUM1, and p53 and negative for CD15, CD30, latent membrane protein 1 (LMP1, and EBV-encoded RNA (EBER. Flow cytometry demonstrated lambda light chain restricted CD5 and CD10 negative B-cells. Fluorescence in situ hybridization studies (FISH were negative for cMYC, BCL2, and BCL6 rearrangements but showed deletion of TP53 and monosomy of chromosome 17. Next-generation sequencing studies (NGS revealed numerous genetic alterations including 6 pathogenic mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53(x2 genes and 30 variants of unknown significance (VOUS in ABL1, ASXL1, ATM, BCOR, BCORL1, BRNIP3, CDH2, CDKN2A, DNMT3A, ETV6, EZH2, FBXW7, KIT, NF1, RUNX1, SETPB1, SF1, SMC1A, STAG2, TET2, TP53, and U2AF2.

S(+)-ibuprofen destabilizes MYC/MYCN and AKT, increases p53 expression, and induces unfolded protein response and favorable phenotype in neuroblastoma cell lines.

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Ikegaki, Naohiko; Hicks, Sakeenah L; Regan, Paul L; Jacobs, Joshua; Jumbo, Amina S; Leonhardt, Payton; Rappaport, Eric F; Tang, Xao X

2014-01-01

Neuroblastoma is a common pediatric solid tumor that exhibits a striking clinical bipolarity: favorable and unfavorable. The survival rate of children with unfavorable neuroblastoma remains low among all childhood cancers. MYCN and MYC play a crucial role in determining the malignancy of unfavorable neuroblastomas, whereas high-level expression of the favorable neuroblastoma genes is associated with a good disease outcome and confers growth suppression of neuroblastoma cells. A small fraction of neuroblastomas harbors TP53 mutations at diagnosis, but a higher proportion of the relapse cases acquire TP53 mutations. In this study, we investigated the effect of S(+)-ibuprofen on neuroblastoma cell lines, focusing on the expression of the MYCN, MYC, AKT, p53 proteins and the favorable neuroblastoma genes in vitro as biomarkers of malignancy. Treatment of neuroblastoma cell lines with S(+)-ibuprofen resulted in a significant growth suppression. This growth effect was accompanied by a marked decrease in the expression of MYC, MYCN, AKT and an increase in p53 expression in neuroblastoma cell lines without TP53 mutation. In addition, S(+)-ibuprofen enhanced the expression of some favorable neuroblastoma genes (EPHB6, CD44) and genes involved in growth suppression and differentiation (EGR1, EPHA2, NRG1 and SEL1L). Gene expression profile and Ingenuity pathway analyses using TP53-mutated SKNAS cells further revealed that S(+)-ibuprofen suppressed molecular pathways associated with cell growth and conversely enhanced those of cell cycle arrest and the unfolded protein response. Collectively, these results suggest that S(+)-ibuprofen or its related compounds may have the potential for therapeutic and/or palliative use for unfavorable neuroblastoma.

Haplotype analysis of TP53 polymorphisms, Arg72Pro and Ins16, in BRCA1 and BRCA2 mutation carriers of French Canadian descent

International Nuclear Information System (INIS)

Cavallone, Luca; Arcand, Suzanna L; Maugard, Christine; Ghadirian, Parviz; Mes-Masson, Anne-Marie; Provencher, Diane; Tonin, Patricia N

2008-01-01

The TP53 polymorphisms Arg72Pro (Ex4+199 G>C) and Ins16 (IVS3+24 ins16) have been proposed to modify risk of breast cancer associated with germline BRCA1 and BRCA2 mutations. Allele frequencies of these polymorphisms were investigated to determine if they modify risk in BRCA mutation carriers in breast cancer cases drawn from French Canadian cancer families, a population shown to exhibit strong founder effects. The frequencies of the TP53 alleles, genotypes and haplotypes of 157 index breast cancer cases comprised of 42 BRCA1 mutation carriers, 57 BRCA2 mutation carriers, and 58 BRCA mutation-negative cases, where each case was drawn from independently ascertained families were compared. The effect of TP53 variants on the age of diagnosis was also investigated for these groups. The TP53 polymorphisms were also investigated in 112 women of French Canadian descent with no personal history of cancer. The BRCA mutation-positive groups had the highest frequency of homozygous carriers of the 72Pro allele compared with mutation-negative group. The TP53 polymorphisms exhibited linkage disequilibrium (p < 0.001), where the 72Arg and Ins16minus alleles occurred in strong disequilibrium. The highest frequency of carriers of Ins16minus-72Arg haplotype occurred in the BRCA mutation-negative groups. The BRCA1 mutation carriers homozygous for the 72Pro allele had the youngest ages of diagnosis of breast cancer. However none of these observations were statistically significant. In contrast, the BRCA2 mutation carriers homozygous for the 72Pro allele had a significantly older age of diagnosis of breast cancer (p = 0.018). Moreover, in this group, the mean age of diagnosis of breast cancer in carriers of the Ins16minus-72Arg haplotype was significantly younger than that of the individuals who did not this carry this haplotype (p = 0.009). We observed no significant association of breast cancer risk with TP53 genetic variants based on BRCA1/2 mutation carrier status. Although the

TP53 codon 72 polymorphism and cervical cancer : a pooled analysis of individual data from 49 studies

NARCIS (Netherlands)

Klug, Stefanie J.; Ressing, Meike; Koenig, Jochem; Abba, Martin C.; Agorastos, Theodoros; Brenna, Sylvia M. F.; Ciotti, Marco; Das, B. R.; Del Mistro, Annarosa; Dybikowska, Aleksandra; Giuliano, Anna R.; Gudleviciene, Zivile; Gyllensten, Ulf; Haws, Andrea L. F.; Helland, Aslaug; Herrington, C. Simon; Hildesheim, Alan; Humbey, Olivier; Jee, Sun H.; Kim, Jae Weon; Madeleine, Margaret M.; Menczer, Joseph; Ngan, Hextan Y. S.; Nishikawa, Akira; Niwa, Yoshimitsu; Pegoraro, Rosemary; Pillai, M. R.; Ranzani, Gulielmina; Rezza, Giovanni; Rosenthal, Adam N.; Roychoudhury, Susanta; Saranath, Dhananjaya; Schmitt, Virginia M.; Sengupta, Sharmila; Settheetham-Ishida, Wannapa; Shirasawa, Hiroshi; Snijders, Peter J. F.; Stoler, Mark H.; Suarez-Rincon, Angel E.; Szarka, Krisztina; Tachezy, Ruth; Ueda, Masatsugu; van der Zee, Ate G. J.; Doeberitz, Magnus von Knebel; Wu, Ming-Tsang; Yamashita, Tsuyoshi; Zehbe, Ingeborg; Blettner, Maria

Background Cervical cancer is caused primarily by human papillomaviruses (HPV). The polymorphism rs1042522 at codon 72 of the TP53 tumour-suppressor gene has been investigated as a genetic cofactor. More than 80 studies were done between 1998 and 2006, after it was initially reported that women who

Tumor hypoxia, p53, and prognosis in cervical cancers

International Nuclear Information System (INIS)

Haensgen, Gabriele; Krause, Ulf; Becker, Axel; Stadler, Peter; Lautenschlaeger, Christine; Wohlrab, Wolfgang; Rath, Friedrich W.; Molls, Michael; Dunst, Juergen

2001-01-01

=0.01). Sixty of the 70 tumors showed positive immunohistologic staining for p53 protein (transformed p53=tp53), and 10/70 were negative (wild-type p53=wtp53); p53 expression had no significant impact on survival (50% for tp53 vs. 79% for wtp53, p=0.11). FIGO stage and anemia had no impact on p53 expression. Forty-nine of 70 tumors were hypoxic (HF5+), and 21 showed no hypoxia (HF5-). Hypoxic carcinomas were more frequently positive for p53 as compared to nonhypoxic tumors (27% vs. 13%, p=0.011) and showed a trend toward a lower survival (48% vs. 70%, p = 0.07). In a further multivariate analysis, the impact of a combination of p53 expression and hypoxia on survival was examined. After adjusting for FIGO stage and pretreatment anemia, patients with wtp53 tumors had the best prognosis (3-year survival 79%) followed by tp53-HF5(-) patients (57%), and the most unfavorable prognosis was observed for tp53-HF5(+) patients (47%). The DNA index was higher in tp53 carcinomas compared to wtp53 tumors, 1.97±0.4 vs. 1.67±0.1, p=0.05. The highest DNA index was found in hypoxic tumors with transformed p53 (2.2±3.1). Conclusions: Advanced stage and pretreatment hemoglobin level are independent prognostic factors in cervical carcinomas. The immunohistologic detection of (a functionally inactive) p53 and the presence of hypoxia had no prognostic impact, if analyzed as single parameters. However, the combination of both parameters was able to discriminate different prognostic subgroups. Moreover, hypoxic cancers were more often immunohistologically positive for tp53 protein and had a higher DNA index with the highest DNA index in tumors with both hypoxia and tp53 protein expression. These findings in summary support the theory that the tumor's microenvironment may influence the biologic behavior via hypoxia

LUNG TUMOR KRAS AND TP53 MUTATIONS IN NON-SMOKERS REFLECT EXPOSURE TO PAH-RICH COAL COMBUSTION EMISSIONS

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Abstract We determined the TP53 and codon 12 KRAS mutations in lung tumors from 24 nonsmokers whose tumors were associated with exposure to smoky coal. Among any tumors studied previously, these showed the highest percentage of mutations that (a) were G -+ T transver...

Influence of tumour suppressor gene (TP53, BRCA1 and BRCA2) polymorphisms on polycystic ovary syndrome in South Indian women.

Science.gov (United States)

Siddamalla, Swapna; Reddy, Tumu Venkat; Govatati, Suresh; Guruvaiah, Praveen; Deenadayal, Mamata; Shivaji, Sisinthy; Bhanoori, Manjula

2018-05-24

Polycystic Ovary Syndrome (PCOS) is a heterogeneous multifactorial endocrine metabolic disorder. In addition to hyperandrogenism, acne, hirsutism, obesity, oligoanovulation and infertility, insulin resistance is also a common feature in women of PCOS. Tumor suppressor genes (TSGs) perform essential function in the maintenance of genomic stability and regulatory pathways influencing the activity of several replication and transcription factors. The main aim of this study was to investigate the association of Single Nucleotide Polymorphisms of TP53, BRCA1and BRCA2 genes with the susceptibility to PCOS in South Indian women. Present study investigated association between TP53 gene (rs1042522 G/C), BRCA1 (rs71361504 -/GTT, rs3092986 T/C) and BRCA2 (rs206118 A/G) and, SNPs and PCOS risk. Genotyping of TSGs was carried out on DNA from PCOS patients (n = 110) and controls (n = 130) of South Indian origin by polymerase chain reaction (PCR) and confirmed by sequencing analysis. The genotype frequency and allele distributions of cases and controls were analyzed using Fisher's exact test. Haplotype frequencies for multiple loci and the standardized disequilibrium coefficient (D') for pair wise linkage disequilibrium (LD) were assessed by Haploview Software. Significant increase in frequencies ofTP53 (rs1042522 G/C), BRCA1 (rs71361504 -/GTT, rs3092986 T/C) genotypes and alleles in patients compared to controls. In addition, the frequency of the C/T (P = 0.002) and A/C (P = 0.012) haplotype was also significantly elevated in patients. But BRCA2 (rs206118 A/G) did not show significant association with PCOS. The TP53 and BRCA1 may constitute an inheritable risk factor for PCOS in South Indian women. Copyright © 2018 Elsevier B.V. All rights reserved.

Inactivation and inducible oncogenic mutation of p53 in gene targeted pigs.

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Simon Leuchs

Full Text Available Mutation of the tumor suppressor p53 plays a major role in human carcinogenesis. Here we describe gene-targeted porcine mesenchymal stem cells (MSCs and live pigs carrying a latent TP53(R167H mutant allele, orthologous to oncogenic human mutant TP53(R175H and mouse Trp53(R172H, that can be activated by Cre recombination. MSCs carrying the latent TP53(R167H mutant allele were analyzed in vitro. Homozygous cells were p53 deficient, and on continued culture exhibited more rapid proliferation, anchorage independent growth, and resistance to the apoptosis-inducing chemotherapeutic drug doxorubicin, all characteristic of cellular transformation. Cre mediated recombination activated the latent TP53(R167H allele as predicted, and in homozygous cells expressed mutant p53-R167H protein at a level ten-fold greater than wild-type MSCs, consistent with the elevated levels found in human cancer cells. Gene targeted MSCs were used for nuclear transfer and fifteen viable piglets were produced carrying the latent TP53(R167H mutant allele in heterozygous form. These animals will allow study of p53 deficiency and expression of mutant p53-R167H to model human germline, or spontaneous somatic p53 mutation. This work represents the first inactivation and mutation of the gatekeeper tumor suppressor gene TP53 in a non-rodent mammal.

Sex reversal in zebrafish fancl mutants is caused by Tp53-mediated germ cell apoptosis.

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Adriana Rodríguez-Marí

2010-07-01

Full Text Available The molecular genetic mechanisms of sex determination are not known for most vertebrates, including zebrafish. We identified a mutation in the zebrafish fancl gene that causes homozygous mutants to develop as fertile males due to female-to-male sex reversal. Fancl is a member of the Fanconi Anemia/BRCA DNA repair pathway. Experiments showed that zebrafish fancl was expressed in developing germ cells in bipotential gonads at the critical time of sexual fate determination. Caspase-3 immunoassays revealed increased germ cell apoptosis in fancl mutants that compromised oocyte survival. In the absence of oocytes surviving through meiosis, somatic cells of mutant gonads did not maintain expression of the ovary gene cyp19a1a and did not down-regulate expression of the early testis gene amh; consequently, gonads masculinized and became testes. Remarkably, results showed that the introduction of a tp53 (p53 mutation into fancl mutants rescued the sex-reversal phenotype by reducing germ cell apoptosis and, thus, allowed fancl mutants to become fertile females. Our results show that Fancl function is not essential for spermatogonia and oogonia to become sperm or mature oocytes, but instead suggest that Fancl function is involved in the survival of developing oocytes through meiosis. This work reveals that Tp53-mediated germ cell apoptosis induces sex reversal after the mutation of a DNA-repair pathway gene by compromising the survival of oocytes and suggests the existence of an oocyte-derived signal that biases gonad fate towards the female developmental pathway and thereby controls zebrafish sex determination.

Immunoexpression of P16INK4a, Rb and TP53 proteins in bronchiolar columnar cell dysplasia (BCCD in lungs resected due to primary non-small cell lung cancer.

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Lech Chyczewski

2008-02-01

Full Text Available Lung cancer is the leading cause of death worldwide. High mortality comes out mainly of the fact that majority of the cases are diagnosed in advanced stadium. An expanded diagnostics of precancerous conditions would certainly contribute to lowering the mortality rate. Many of the molecular changes accompanying the multistep cancer development could be observed using the immunohistochemistry method. In this paper we describe the morphology and cell cycle proteins immunoexpression of the novel probable preinvasive lesion - bronchiolar columnar cell dysplasia (BCCD. Thirty cases of BCCD selected out of 193 patients population, treated for primary non-small cell lung cancer were investigated. Loss of P16INK4a protein was observed in 70% of all cases and was statistically significant in patients with adenocarcinoma. Two cases show abnormal cytoplasmic localization of this protein. TP53 protein accumulates in 26.7% of all BCCD. Rb protein was active in 48.3% of the BCCD cases. In two cases we observed differentiation of the cells composing BCCD into multilayer epithelium of the squamous type, which occurs with formation of desmosomes. We suppose that BCCD may be preneoplastic lesion leading to adenocarcinoma as well as to peripheral squamous cell lung cancer.

Fetal colon cell line FHC exhibits tumorigenic phenotype, complex karyotype, and TP53 gene mutation

Czech Academy of Sciences Publication Activity Database

Souček, Karel; Jirsová, Pavla; Brázdová, Marie; Hýžďalová, Martina; Kočí, Lenka; Vydra, D.; Trojanec, R.; Pernicová, Zuzana; Lentvorská, L.; Hajdúch, M.; Hofmanová, Jiřina; Kozubík, Alois

2010-01-01

Roč. 197, č. 2 (2010), s. 107-116 ISSN 0165-4608 R&D Projects: GA MŠk ME 919; GA ČR(CZ) GA204/07/0834; GA ČR(CZ) GA204/08/1560; GA AV ČR(CZ) 1QS500040507; GA MZd NS9600 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : colon epithelial cells * TP53 * MYC Subject RIV: BO - Biophysics Impact factor: 1.551, year: 2010

Mutation screening of the TP53 gene by temporal temperature gradient gel electrophoresis.

Science.gov (United States)

Sørlie, Therese; Johnsen, Hilde; Vu, Phuong; Lind, Guro Elisabeth; Lothe, Ragnhild; Børresen-Dale, Anne-Lise

2005-01-01

A protocol for detection of mutations in the TP53 gene using temporal temperature gradient gel electrophoresis (TTGE) is described. TTGE is a mutation detection technique that separates DNA fragments differing by single base pairs according to their melting properties in a denaturing gel. It is based on constant denaturing conditions in the gel combined with a temperature gradient during the electrophoretic run. This method combines some of the advantages of the related techniques denaturing gradient gel electrophoresis (DGGE) and constant denaturant gel electrophoresis (CDGE) and eliminates some of the problems. The result is a rapid and sensitive screening technique that is robust and easily set up in smaller laboratory environments.

Mutation screening of the TP53 gene by temporal temperature gel electrophoresis (TTGE).

Science.gov (United States)

Sørlie, Therese; Johnsen, Hilde; Vu, Phuong; Lind, Guro Elisabeth; Lothe, Ragnhild; Børresen-Dale, Anne-Lise

2014-01-01

A protocol for detection of mutations in the TP53 gene using temporal temperature gradient electrophoresis (TTGE) is described. TTGE is a mutation detection technique that separates DNA fragments differing by single base pairs according to their melting properties in a denaturing gel. It is based on constant denaturing conditions in the gel combined with a temperature gradient during the electrophoretic run. This method combines some of the advantages of the related techniques, denaturing gradient gel electrophoresis and constant denaturant gel electrophoresis, and eliminates some of the problems. The result is a rapid and sensitive screening technique which is robust and easily set up in smaller laboratory environments.

Aberrant TP53 detected by combining immunohistochemistry and DNA-FISH improves Barrett's esophagus progression prediction: a prospective follow-up study

NARCIS (Netherlands)

Davelaar, Akueni L.; Calpe, Silvia; Lau, Liana; Timmer, Margriet R.; Visser, Mike; ten Kate, Fiebo J.; Parikh, Kaushal B.; Meijer, Sybren L.; Bergman, Jacques J.; Fockens, Paul; Krishnadath, Kausilia K.

2015-01-01

Barrett's esophagus (BE) goes through a sequence of low grade dysplasia (LGD) and high grade dysplasia (HGD) to esophageal adenocarcinoma (EAC). The current gold standard for BE outcome prediction, histopathological staging, can be unreliable. TP53 abnormalities may serve as prognostic biomarkers.

Aberrant TP53 detected by combining immunohistochemistry and DNA-FISH improves Barrett's esophagus progression prediction : A prospective follow-up study

NARCIS (Netherlands)

Davelaar, Akueni L.; Calpe, Silvia; Lau, Liana; Timmer, Margriet R.; Visser, Mike; ten Kate, Fiebo J.; Parikh, Kaushal B.; Meijer, Sybren L.; Bergman, Jacques J.; Fockens, Paul; Krishnadath, Kausilia K.

2015-01-01

Barrett's esophagus (BE) goes through a sequence of low grade dysplasia (LGD) and high grade dysplasia (HGD) to esophageal adenocarcinoma (EAC). The current gold standard for BE outcome prediction, histopathological staging, can be unreliable. TP53 abnormalities may serve as prognostic biomarkers.

Identification of TP53 as an Acute Lymphocytic Leukemia Susceptibility Gene Through Exome Sequencing

Science.gov (United States)

Powell, Bradford C.; Jiang, Lichun; Muzny, Donna M.; Treviño, Lisa R.; Dreyer, ZoAnn E.; Strong, Louise C.; Wheeler, David A.; Gibbs, Richard A.; Plon, Sharon E.

2014-01-01

Although acute lymphocytic leukemia (ALL) is the most common childhood cancer, genetic predisposition to ALL remains poorly understood. Whole-exome sequencing was performed in an extended kindred in which five individuals had been diagnosed with leukemia. Analysis revealed a nonsense variant of TP53 which has been previously reported in families with sarcomas and other typical Li Fraumeni syndrome-associated cancers but never in a familial leukemia kindred. This unexpected finding enabled identification of an appropriate sibling bone marrow donor and illustrates that exome sequencing will reveal atypical clinical presentations of even well-studied genes. PMID:23255406

Wee1 Kinase Inhibitor AZD1775 Radiosensitizes Hepatocellular Carcinoma Regardless of TP53 Mutational Status Through Induction of Replication Stress

Energy Technology Data Exchange (ETDEWEB)

Cuneo, Kyle C., E-mail: kcuneo@umich.edu; Morgan, Meredith A.; Davis, Mary A.; Parcels, Leslie A.; Parcels, Joshua; Karnak, David; Ryan, Caila; Liu, Na; Maybaum, Jonathan; Lawrence, Theodore S.

2016-06-01

Purpose: Wee1 kinase inhibitors are effective radiosensitizers in cells lacking a G{sub 1} checkpoint. In this study we examined the potential effect of Wee1 kinase inhibition on inducing replication stress in hepatocellular carcinoma (HCC). Methods and Materials: Five independent datasets from the Oncomine database comparing gene expression in HCC compared to normal tissue were combined and specific markers associated with Wee1 sensitivity were analyzed. We then performed a series of in vitro experiments to study the effect of Wee1 inhibition on irradiated HCC cell lines with varying p53 mutational status. Clonogenic survival assays and flow cytometry using anti-γH2AX and phospho-histone H3 antibodies with propidium iodide were performed to study the effect of AZD1775 on survival, cell cycle, and DNA repair. Additionally, nucleoside enriched medium was used to examine the effect of altering nucleotide pools on Wee1 targeted radiation sensitization. Results: Our analysis of the Oncomine database found high levels of CDK1 and other cell cycle regulators indicative of Wee1 sensitivity in HCC. In our in vitro experiments, treatment with AZD1775 radiosensitized and chemosensitized Hep3B, Huh7, and HepG2 cell lines and was associated with delayed resolution of γH2AX foci and the induction of pan-nuclear γH2AX staining. Wee1 inhibition attenuated radiation-induced G{sub 2} arrest in the Hep3B (TP53 null) and Huh7 (TP53 mutant) cell lines but not in the TP53 wild-type cell line HepG2. Supplementation with nucleosides reversed the radiation-sensitizing effect of AZD1775 and reduced the amount of cells with pan-nuclear γH2AX staining after radiation. Conclusions: Radiation sensitization with Wee1 inhibition occurs in cells regardless of their p53 mutational status. In this study we show for the first time that replication stress via the overconsumption of nucleotides plays an important role in AZD1775-induced radiation sensitization.

NSAIDs modulate CDKN2A, TP53, and DNA content risk for progression to esophageal adenocarcinoma.

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Patricia C Galipeau

2007-02-01

Full Text Available Somatic genetic CDKN2A, TP53, and DNA content abnormalities are common in many human cancers and their precursors, including esophageal adenocarcinoma (EA and Barrett's esophagus (BE, conditions for which aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs have been proposed as possible chemopreventive agents; however, little is known about the ability of a biomarker panel to predict progression to cancer nor how NSAID use may modulate progression. We aimed to evaluate somatic genetic abnormalities with NSAIDs as predictors of EA in a prospective cohort study of patients with BE.Esophageal biopsies from 243 patients with BE were evaluated at baseline for TP53 and CDKN2A (p16 alterations, tetraploidy, and aneuploidy using sequencing; loss of heterozygosity (LOH; methylation-specific PCR; and flow cytometry. At 10 y, all abnormalities, except CDKN2A mutation and methylation, contributed to EA risk significantly by univariate analysis, ranging from 17p LOH (relative risk [RR] = 10.6; 95% confidence interval [CI] 5.2-21.3, p < 0.001 to 9p LOH (RR = 2.6; 95% CI 1.1-6.0, p = 0.03. A panel of abnormalities including 17p LOH, DNA content tetraploidy and aneuploidy, and 9p LOH was the best predictor of EA (RR = 38.7; 95% CI 10.8-138.5, p < 0.001. Patients with no baseline abnormality had a 12% 10-y cumulative EA incidence, whereas patients with 17p LOH, DNA content abnormalities, and 9p LOH had at least a 79.1% 10-y EA incidence. In patients with zero, one, two, or three baseline panel abnormalities, there was a significant trend toward EA risk reduction among NSAID users compared to nonusers (p = 0.01. The strongest protective effect was seen in participants with multiple genetic abnormalities, with NSAID nonusers having an observed 10-y EA risk of 79%, compared to 30% for NSAID users (p < 0.001.A combination of 17p LOH, 9p LOH, and DNA content abnormalities provided better EA risk prediction than any single TP53, CDKN2A, or DNA content

Microdissecção e captura a laser na investigação do gene TP53 em tecidos incluídos em parafina Laser-capture microdissection for TP53 gene analysis in paraffin-embedded tissues

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Shadia Muhammad Ihlaseh

2007-02-01

Full Text Available INTRODUÇÃO: Microdissecção e captura a laser (MCL é uma técnica de desenvolvimento recente que permite a coleta de células individuais ou pequeno conjunto de células para análise molecular. Atualmente, no Brasil, há raros microscópios para MCL, de modo que a divulgação dos procedimentos inerentes a essa técnica é oportuna para destacar seu amplo potencial para diagnóstico e investigação. OBJETIVO: Este trabalho descreve a padronização dos procedimentos de MCL e de extração de DNA de material fixado em formalina e incluído em parafina. MATERIAL E MÉTODOS: Foram estudados o éxon 8 do gene TP53 e o gene da ciclofilina em amostras de tecido normal e de neoplasias de fígado e rim provenientes de modelo de carcinogênese química induzida em rato. A extração do DNA foi comprovada por reação em cadeia da polimerase (nested-PCR. RESULTADOS: Foram padronizados os procedimentos de preparo dos cortes histológicos, de microdissecção e captura a laser e de obtenção de seqüências gênicas pela reação de nested-PCR para tecidos incluídos em parafina. Obtivemos amplificação de 48,3% das amostras para o éxon 8 do gene TP53 e 51,7% para o gene da ciclofilina. Considerando pelo menos um dos dois segmentos gênicos, foram amplificadas 79,3% das amostras. DISCUSSÃO E CONCLUSÃO: A extração de DNA de tecidos fixados em formalina e incluídos em parafina e a técnica de nested-PCR foram adequadamente padronizadas para produtos gênicos de interesse, obtidos de material coletado por MCL. Esses procedimentos podem ser úteis para a obtenção de seqüências de DNA de arquivos para análise molecular.BACKGORUND: Laser-capture micro-dissection (LCM is a recently developed procedure that provides single cells or specific cell groups for molecular analysis. Currently, there are few LCM systems in Brazil, in such a way that it is necessary to disseminate the technical procedures inherent to the methodology, and also to

Association of TP53 codon 72 and CDH1 genetic polymorphisms with colorectal cancer risk in Bangladeshi population.

Science.gov (United States)

Rivu, Sanzana Fareen; Apu, Mohd Nazmul Hasan; Shabnaz, Samia; Nahid, Noor Ahmed; Islam, Md Reazul; Al-Mamun, Mir Md Abdullah; Nahar, Zabun; Rabbi, Sikder Nahidul Islam; Ahmed, Maizbha Uddin; Islam, Mohammad Safiqul; Hasnat, Abul

2017-08-01

Till now no pharmacogenetic study of TP53 codon 72 (Arg72Pro) and CDH1 rs16260 (-160Ccolorectal cancer. So the aim of the study is to determine whether there is an elevated risk of colorectal cancer development with TP53 codon 72 and CDH1 rs16260 genetic polymorphism in Bangladeshi population for the first time. To investigate the association of these two SNPs, we conducted a case-control study with 288 colorectal cancer patients and 295 healthy volunteers by using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. We found an increased risk of association between Arg/Pro heterozygosity (adjusted OR=2.58, 95% CI=1.77-3.77, pcolorectal cancer predisposition. In case of CDH1 rs16260 polymorphism, C/A heterozygous and A/A mutant homozygous are significantly (pcolorectal cancer risk with adjusted OR of 1.94 and 2.63, respectively. The combined genotype of C/A and A/A was also found to be strongly associated with colorectal cancer risk compared to C/C genotype (adjusted OR=2.02, 95% CI=1.42-2.87, pcolorectal cancer development in Bangladeshi population. Copyright © 2017 Elsevier Ltd. All rights reserved.

TP Atlas: integration and dissemination of advances in Targeted Proteins Research Program (TPRP)-structural biology project phase II in Japan.

Science.gov (United States)

Iwayanagi, Takao; Miyamoto, Sei; Konno, Takeshi; Mizutani, Hisashi; Hirai, Tomohiro; Shigemoto, Yasumasa; Gojobori, Takashi; Sugawara, Hideaki

2012-09-01

The Targeted Proteins Research Program (TPRP) promoted by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan is the phase II of structural biology project (2007-2011) following the Protein 3000 Project (2002-2006) in Japan. While the phase I Protein 3000 Project put partial emphasis on the construction and maintenance of pipelines for structural analyses, the TPRP is dedicated to revealing the structures and functions of the targeted proteins that have great importance in both basic research and industrial applications. To pursue this objective, 35 Targeted Proteins (TP) Projects selected in the three areas of fundamental biology, medicine and pharmacology, and food and environment are tightly collaborated with 10 Advanced Technology (AT) Projects in the four fields of protein production, structural analyses, chemical library and screening, and information platform. Here, the outlines and achievements of the 35 TP Projects are summarized in the system named TP Atlas. Progress in the diversified areas is described in the modules of Graphical Summary, General Summary, Tabular Summary, and Structure Gallery of the TP Atlas in the standard and unified format. Advances in TP Projects owing to novel technologies stemmed from AT Projects and collaborative research among TP Projects are illustrated as a hallmark of the Program. The TP Atlas can be accessed at http://net.genes.nig.ac.jp/tpatlas/index_e.html .

Targeting the p53 Pathway in Ewing Sarcoma

Science.gov (United States)

Neilsen, Paul M.; Pishas, Kathleen I.; Callen, David F.; Thomas, David M.

2011-01-01

The p53 tumour suppressor plays a pivotal role in the prevention of oncogenic transformation. Cancers frequently evade the potent antitumour surveillance mechanisms of p53 through mutation of the TP53 gene, with approximately 50% of all human malignancies expressing dysfunctional, mutated p53 proteins. Interestingly, genetic lesions in the TP53 gene are only observed in 10% of Ewing Sarcomas, with the majority of these sarcomas expressing a functional wild-type p53. In addition, the p53 downstream signaling pathways and DNA-damage cell cycle checkpoints remain functionally intact in these sarcomas. This paper summarizes recent insights into the functional capabilities and regulation of p53 in Ewing Sarcoma, with a particular focus on the cross-talk between p53 and the EWS-FLI1 gene rearrangement frequently associated with this disease. The development of several activators of p53 is discussed, with recent evidence demonstrating the potential of small molecule p53 activators as a promising systemic therapeutic approach for the treatment of Ewing Sarcomas with wild-type p53. PMID:21197471

FOXP1 and TP63 involvement in the progression of myelodysplastic syndrome with 5q- and additional cytogenetic abnormalities

International Nuclear Information System (INIS)

L’Abbate, Alberto; Tagliafico, Enrico; Minoia, Carla; De Tullio, Giacoma; Guarini, Attilio; Testoni, Nicoletta; Agostinelli, Claudio; Storlazzi, Clelia Tiziana; Lo Cunsolo, Crocifissa; Macrì, Ettore; Iuzzolino, Paolo; Mecucci, Cristina; Doglioni, Claudio; Coco, Michelina; Muscarella, Lucia Anna; Salati, Simona

2014-01-01

The progression of low-risk del(5q) myelodysplastic syndrome to acute myeloid leukemia is increased when associated with mutations of TP53, or with additional chromosomal abnormalities. However, to date the prognostic impact and molecular consequences of these rearrangements were poorly investigated. Single additional alterations to del(5q) by balanced chromosome rearrangements were rarely found in myelodysplasia. In particular, balanced alterations involving TP63 and FOXP1 genes were never reported in the literature. Here we report on a 79-year woman with an aggressive form of myelodysplastic syndrome with del(5q), no TP53 mutation, and a novel complex rearrangement of chromosome 3 in bone marrow cells. Our results revealed that the FOXP1 and TP63 genes were both relocated along chromosome 3. Strikingly, immunohistochemistry analysis showed altered protein levels, disclosing that this rearrangement triggered the expression of FOXP1 and TP63 genes. FOXP1 was also found activated in other patients with myelodysplasia and acute myeloid leukemia, showing that it is an important, recurrent event. We document an apparent role of FOXP1 and TP63, up to now poorly documented, in the progression of MDS in our patient who is lacking mutations in the TP53 tumor suppressor gene normally associated with poor outcome in myelodysplastic syndrome with 5q-. Finally, our results may suggest a possible broader role of FOXP1 in the pathogenesis and progression of myelodysplasia and acute myeloid leukemia

Mutational profile and prognostic significance of TP53 in diffuse large B-cell lymphoma patients treated with R-CHOP

DEFF Research Database (Denmark)

Xu-Monette, Zijun Y; Wu, Lin; Visco, Carlo

2012-01-01

TP53 mutation is an independent marker of poor prognosis in patients with diffuse large B-cell lymphoma (DLBCL) treated with cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (CHOP) therapy. However, its prognostic value in the rituximab immunochemotherapy era remains undefined. ...... for stratifying R-CHOP-treated patients into distinct prognostic subsets and has significant value in the design of future therapeutic strategies....

Reduced rate of human papillomavirus infection and genetic overtransmission of TP53 72C polymorphic variant lower cervical cancer incidence.

Science.gov (United States)

Alsbeih, Ghazi A; Al-Harbi, Najla M; Bin Judia, Sara S; Khoja, Hatim A; Shoukri, Mohamed M; Tulbah, Asma M

2017-07-01

Cervical cancer is a predominantly human papillomavirus (HPV)-driven disease worldwide. However, its incidence is unexplainably low in western Asia, including Saudi Arabia. Using this paradigm, we investigated the role of HPV infection rate and host genetic predisposition in TP53 G72C single nucleotide polymorphism (SNP) presumed to affect cancer incidence. Patients treated between 1990 and 2012 were reviewed, and a series of 232 invasive cervical cancer cases were studied and compared with 313 matched controls without cancer. SNP was genotyped by way of direct sequencing. HPV linear array analysis was used to detect and genotype HPV in tumor samples. The incidence of cervical cancer revealed bimodal peaks at 42.5 years, with a slighter rebound at 60.8 years. Among all cases, 77% were HPV-positive and 16 HPV genotypes were detected-mostly genotypes 16 (75%) and 18 (9%)-with no difference by age, histology, or geographical region. Although the TP53 G72C genotype was not associated with overall cervical cancer risk, it was significantly associated with HPV positivity (odds ratio, 0.57; 95% confidence interval, 0.36-0.90; P = .016). Furthermore, the variant C allele was significantly overtransmitted in the population (P Cervical cancer incidence displays bimodal curve peaking at a young age with secondary rebound at older age. The combination of relative low HPV infection and variant TP53 72C allele overtransmission provide a plausible explanation for the low incidence of cervical cancer in our population. Therefore, HPV screening and host SNP genotyping may provide more relevant biomarkers to gauge the risk of developing cervical cancer. Cancer 2017;123:2459-66. © 2017 American Cancer Society. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

A protein-truncating R179X variant in RNF186 confers protection against ulcerative colitis

NARCIS (Netherlands)

Rivas, Manuel A.; Graham, Daniel; Sulem, Patrick; Stevens, Christine; Desch, A. Nicole; Goyette, Philippe; Gudbjartsson, Daniel; Jonsdottir, Ingileif; Thorsteinsdottir, Unnur; Degenhardt, Frauke; Mucha, Soeren; Kurki, Mitja I.; Li, Dalin; D'Amato, Mauro; Annese, Vito; Vermeire, Severine; Weersma, Rinse K.; Halfvarson, Jonas; Paavola-Sakki, Paulina; Lappalainen, Maarit; Lek, Monkol; Cummings, Beryl; Tukiainen, Taru; Haritunians, Talin; Halme, Leena; Koskinen, Lotta L. E.; Ananthakrishnan, Ashwin N.; Luo, Yang; Heap, Graham A.; Visschedijk, Marijn C.; MacArthur, Daniel G.; Neale, Benjamin M.; Ahmad, Tariq; Anderson, Carl A.; Brant, Steven R.; Duerr, Richard H.; Silverberg, Mark S.; Cho, Judy H.; Palotie, Aarno; Saavalainen, Paivi; Kontula, Kimmo; Farkkila, Martti; McGovern, Dermot P. B.; Franke, Andre; Stefansson, Kari; Rioux, John D.; Xavier, Ramnik J.; Daly, Mark J.

Protein-truncating variants protective against human disease provide in vivo validation of therapeutic targets. Here we used targeted sequencing to conduct a search for protein-truncating variants conferring protection against inflammatory bowel disease exploiting knowledge of common variants

Identification of a rhodium(iii) complex as a Wee1 inhibitor against TP53-mutated triple-negative breast cancer cells.

Science.gov (United States)

Yang, Guan-Jun; Zhong, Hai-Jing; Ko, Chung-Nga; Wong, Suk-Yu; Vellaisamy, Kasipandi; Ye, Min; Ma, Dik-Lung; Leung, Chung-Hang

2018-03-06

The rhodium(iii) complex 1 was identified as a potent Wee1 inhibitor in vitro and in cellulo. It decreased Wee1 activity and unscheduled mitotic entry, and induced cell damage and death in TP53-mutated triple-negative breast cancer cells. 1 represents a promising scaffold for further development of more potent metal-based Wee1 antagonists.

Phytometabolite Dehydroleucodine Induces Cell Cycle Arrest, Apoptosis, and DNA Damage in Human Astrocytoma Cells through p73/p53 Regulation.

Science.gov (United States)

Bailon-Moscoso, Natalia; González-Arévalo, Gabriela; Velásquez-Rojas, Gabriela; Malagon, Omar; Vidari, Giovanni; Zentella-Dehesa, Alejandro; Ratovitski, Edward A; Ostrosky-Wegman, Patricia

2015-01-01

Accumulating evidence supports the idea that secondary metabolites obtained from medicinal plants (phytometabolites) may be important contributors in the development of new chemotherapeutic agents to reduce the occurrence or recurrence of cancer. Our study focused on Dehydroleucodine (DhL), a sesquiterpene found in the provinces of Loja and Zamora-Chinchipe. In this study, we showed that DhL displayed cytostatic and cytotoxic activities on the human cerebral astrocytoma D384 cell line. With lactone isolated from Gynoxys verrucosa Wedd, a medicinal plant from Ecuador, we found that DhL induced cell death in D384 cells by triggering cell cycle arrest and inducing apoptosis and DNA damage. We further found that the cell death resulted in the increased expression of CDKN1A and BAX proteins. A marked induction of the levels of total TP73 and phosphorylated TP53, TP73, and γ-H2AX proteins was observed in D384 cells exposed to DhL, but no increase in total TP53 levels was detected. Overall these studies demonstrated the marked effect of DhL on the diminished survival of human astrocytoma cells through the induced expression of TP73 and phosphorylation of TP73 and TP53, suggesting their key roles in the tumor cell response to DhL treatment.

The Tp0684 (MglB-2 Lipoprotein of Treponema pallidum: A Glucose-Binding Protein with Divergent Topology.

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Chad A Brautigam

Full Text Available Treponema pallidum, the bacterium that causes syphilis, is an obligate human parasite. As such, it must acquire energy, in the form of carbon sources, from the host. There is ample evidence that the principal source of energy for this spirochete is D-glucose acquired from its environment, likely via an ABC transporter. Further, there is genetic evidence of a D-glucose chemotaxis system in T. pallidum. Both of these processes may be dependent on a single lipidated chemoreceptor: Tp0684, also called TpMglB-2 for its sequence homology to MglB of Escherichia coli. To broaden our understanding of this potentially vital protein, we determined a 2.05-Å X-ray crystal structure of a soluble form of the recombinant protein. Like its namesake, TpMglB-2 adopts a bilobed fold that is similar to that of the ligand-binding proteins (LBPs of other ABC transporters. However, the protein has an unusual, circularly permuted topology. This feature prompted a series of biophysical studies that examined whether the protein's topological distinctiveness affected its putative chemoreceptor functions. Differential scanning fluorimetry and isothermal titration calorimetry were used to confirm that the protein bound D-glucose in a cleft between its two lobes. Additionally, analytical ultracentrifugation was employed to reveal that D-glucose binding is accompanied by a significant conformational change. TpMglB-2 thus appears to be fully functional in vitro, and given the probable central importance of the protein to T. pallidum's physiology, our results have implications for the viability and pathogenicity of this obligate human pathogen.

The Tp0684 (MglB-2) Lipoprotein of Treponema pallidum: A Glucose-Binding Protein with Divergent Topology.

Science.gov (United States)

Brautigam, Chad A; Deka, Ranjit K; Liu, Wei Z; Norgard, Michael V

2016-01-01

Treponema pallidum, the bacterium that causes syphilis, is an obligate human parasite. As such, it must acquire energy, in the form of carbon sources, from the host. There is ample evidence that the principal source of energy for this spirochete is D-glucose acquired from its environment, likely via an ABC transporter. Further, there is genetic evidence of a D-glucose chemotaxis system in T. pallidum. Both of these processes may be dependent on a single lipidated chemoreceptor: Tp0684, also called TpMglB-2 for its sequence homology to MglB of Escherichia coli. To broaden our understanding of this potentially vital protein, we determined a 2.05-Å X-ray crystal structure of a soluble form of the recombinant protein. Like its namesake, TpMglB-2 adopts a bilobed fold that is similar to that of the ligand-binding proteins (LBPs) of other ABC transporters. However, the protein has an unusual, circularly permuted topology. This feature prompted a series of biophysical studies that examined whether the protein's topological distinctiveness affected its putative chemoreceptor functions. Differential scanning fluorimetry and isothermal titration calorimetry were used to confirm that the protein bound D-glucose in a cleft between its two lobes. Additionally, analytical ultracentrifugation was employed to reveal that D-glucose binding is accompanied by a significant conformational change. TpMglB-2 thus appears to be fully functional in vitro, and given the probable central importance of the protein to T. pallidum's physiology, our results have implications for the viability and pathogenicity of this obligate human pathogen.

Truncated forms of viral VP2 proteins fused to EGFP assemble into fluorescent parvovirus-like particles

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Vuento Matti

2006-12-01

Full Text Available Abstract Fluorescence correlation spectroscopy (FCS monitors random movements of fluorescent molecules in solution, giving information about the number and the size of for example nano-particles. The canine parvovirus VP2 structural protein as well as N-terminal deletion mutants of VP2 (-14, -23, and -40 amino acids were fused to the C-terminus of the enhanced green fluorescent protein (EGFP. The proteins were produced in insect cells, purified, and analyzed by western blotting, confocal and electron microscopy as well as FCS. The non-truncated form, EGFP-VP2, diffused with a hydrodynamic radius of 17 nm, whereas the fluorescent mutants truncated by 14, 23 and 40 amino acids showed hydrodynamic radii of 7, 20 and 14 nm, respectively. These results show that the non-truncated EGFP-VP2 fusion protein and the EGFP-VP2 constructs truncated by 23 and by as much as 40 amino acids were able to form virus-like particles (VLPs. The fluorescent VLP, harbouring VP2 truncated by 23 amino acids, showed a somewhat larger hydrodynamic radius compared to the non-truncated EGFP-VP2. In contrast, the construct containing EGFP-VP2 truncated by 14 amino acids was not able to assemble into VLP-resembling structures. Formation of capsid structures was confirmed by confocal and electron microscopy. The number of fluorescent fusion protein molecules present within the different VLPs was determined by FCS. In conclusion, FCS provides a novel strategy to analyze virus assembly and gives valuable structural information for strategic development of parvovirus-like particles.

Identification of a functionally distinct truncated BDNF mRNA splice variant and protein in Trachemys scripta elegans.

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Ganesh Ambigapathy

Full Text Available Brain-derived neurotrophic factor (BDNF has a diverse functional role and complex pattern of gene expression. Alternative splicing of mRNA transcripts leads to further diversity of mRNAs and protein isoforms. Here, we describe the regulation of BDNF mRNA transcripts in an in vitro model of eyeblink classical conditioning and a unique transcript that forms a functionally distinct truncated BDNF protein isoform. Nine different mRNA transcripts from the BDNF gene of the pond turtle Trachemys scripta elegans (tBDNF are selectively regulated during classical conditioning: exon I mRNA transcripts show no change, exon II transcripts are downregulated, while exon III transcripts are upregulated. One unique transcript that codes from exon II, tBDNF2a, contains a 40 base pair deletion in the protein coding exon that generates a truncated tBDNF protein. The truncated transcript and protein are expressed in the naïve untrained state and are fully repressed during conditioning when full-length mature tBDNF is expressed, thereby having an alternate pattern of expression in conditioning. Truncated BDNF is not restricted to turtles as a truncated mRNA splice variant has been described for the human BDNF gene. Further studies are required to determine the ubiquity of truncated BDNF alternative splice variants across species and the mechanisms of regulation and function of this newly recognized BDNF protein.

Identification of a functionally distinct truncated BDNF mRNA splice variant and protein in Trachemys scripta elegans.

Science.gov (United States)

Ambigapathy, Ganesh; Zheng, Zhaoqing; Li, Wei; Keifer, Joyce

2013-01-01

Brain-derived neurotrophic factor (BDNF) has a diverse functional role and complex pattern of gene expression. Alternative splicing of mRNA transcripts leads to further diversity of mRNAs and protein isoforms. Here, we describe the regulation of BDNF mRNA transcripts in an in vitro model of eyeblink classical conditioning and a unique transcript that forms a functionally distinct truncated BDNF protein isoform. Nine different mRNA transcripts from the BDNF gene of the pond turtle Trachemys scripta elegans (tBDNF) are selectively regulated during classical conditioning: exon I mRNA transcripts show no change, exon II transcripts are downregulated, while exon III transcripts are upregulated. One unique transcript that codes from exon II, tBDNF2a, contains a 40 base pair deletion in the protein coding exon that generates a truncated tBDNF protein. The truncated transcript and protein are expressed in the naïve untrained state and are fully repressed during conditioning when full-length mature tBDNF is expressed, thereby having an alternate pattern of expression in conditioning. Truncated BDNF is not restricted to turtles as a truncated mRNA splice variant has been described for the human BDNF gene. Further studies are required to determine the ubiquity of truncated BDNF alternative splice variants across species and the mechanisms of regulation and function of this newly recognized BDNF protein.

Phytometabolite Dehydroleucodine Induces Cell Cycle Arrest, Apoptosis, and DNA Damage in Human Astrocytoma Cells through p73/p53 Regulation.

Directory of Open Access Journals (Sweden)

Natalia Bailon-Moscoso

Full Text Available Accumulating evidence supports the idea that secondary metabolites obtained from medicinal plants (phytometabolites may be important contributors in the development of new chemotherapeutic agents to reduce the occurrence or recurrence of cancer. Our study focused on Dehydroleucodine (DhL, a sesquiterpene found in the provinces of Loja and Zamora-Chinchipe. In this study, we showed that DhL displayed cytostatic and cytotoxic activities on the human cerebral astrocytoma D384 cell line. With lactone isolated from Gynoxys verrucosa Wedd, a medicinal plant from Ecuador, we found that DhL induced cell death in D384 cells by triggering cell cycle arrest and inducing apoptosis and DNA damage. We further found that the cell death resulted in the increased expression of CDKN1A and BAX proteins. A marked induction of the levels of total TP73 and phosphorylated TP53, TP73, and γ-H2AX proteins was observed in D384 cells exposed to DhL, but no increase in total TP53 levels was detected. Overall these studies demonstrated the marked effect of DhL on the diminished survival of human astrocytoma cells through the induced expression of TP73 and phosphorylation of TP73 and TP53, suggesting their key roles in the tumor cell response to DhL treatment.

p53 Aggregates penetrate cells and induce the co-aggregation of intracellular p53.

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Karolyn J Forget

Full Text Available Prion diseases are unique pathologies in which the infectious particles are prions, a protein aggregate. The prion protein has many particular features, such as spontaneous aggregation, conformation transmission to other native PrP proteins and transmission from an individual to another. Protein aggregation is now frequently associated to many human diseases, for example Alzheimer's disease, Parkinson's disease or type 2 diabetes. A few proteins associated to these conformational diseases are part of a new category of proteins, called prionoids: proteins that share some, but not all, of the characteristics associated with prions. The p53 protein, a transcription factor that plays a major role in cancer, has recently been suggested to be a possible prionoid. The protein has been shown to accumulate in multiple cancer cell types, and its aggregation has also been reproduced in vitro by many independent groups. These observations suggest a role for p53 aggregates in cancer development. This study aims to test the «prion-like» features of p53. Our results show in vitro aggregation of the full length and N-terminally truncated protein (p53C, and penetration of these aggregates into cells. According to our findings, the aggregates enter cells using macropinocytosis, a non-specific pathway of entry. Lastly, we also show that once internalized by the cell, p53C aggregates can co-aggregate with endogenous p53 protein. Together, these findings suggest prion-like characteristics for p53 protein, based on the fact that p53 can spontaneously aggregate, these aggregates can penetrate cells and co-aggregate with cellular p53.

The STR polymorphism (AAAATn within the intron 1 of the tumor protein 53 (TP53 locus in 17 populations of different ethnic groups of Africa, America, Asia and Europe

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Jorge Azofeifa

2004-09-01

Full Text Available The STR (AAAATn within intron 1 of the TP53 locus was screened in 17 populations from 3 main ethnic groups: Europeans, Asiatics, and Africans, and from the hybrid population of Costa Rica (1968 samples. Three alleles, 126/7 (bp/copies of the repeat, 131/8 and 136/9 were the most prevalent in all populations. Other alleles rarely reached frequencies of 10% or higher. Observed heterozygosities ranged between 0.351 and 0.829. Patterns of diversity fit well with both the geographic origin of the samples and the history of the populations screened. A statistical test suggests that single-step mutational events have been the main mechanism producing new alleles at this locus. Fixation indexes (R ST for this marker showed an effect of population subdivision on divergence only within the Asiatic group; they were insensitive at the level of major ethnic groups as well as within Africans and within Europeans. Rev. Biol. Trop. 52(3: 645-657. Epub 2004 Dic 15.Se estudió el polimorfismo del microsatélite (AAAATn del intrón 1 del gene TP53 en 17 poblaciones de 3 grupos étnicos: europeos, asiáticos, y africanos subsaharianos, así como de la población híbrida de Costa Rica (en total 1968 muestras. Tres alelos, 126/7 (pares de bases/ copias de la repetición, 131/8 y 136/9 fueron los más frecuentes en todas las poblaciones, aunque se observaron otros alelos usualmente a frecuencias menores al 10%. Las heterocigosis observadas variaron de 0.351 a 0.829. La distribución de la diversidad parece concordar con el origen geográfico de las muestras y con la historia de las poblaciones estudiadas. Una prueba estadística indica que el evento mutacional que más alelos nuevos produce en este marcador es el de un solo paso (expansión o contracción de una sola copia de la repetición. El índice de fijación R ST mostró los efectos de la subdivision de poblaciones sólo dentro del grupo de los asiáticos y mostró falta de sensibilidad cuando los grupos

Analysis of P53 mutations and their expression in 56 colorectal cancer cell lines

DEFF Research Database (Denmark)

Liu, Ying; Bodmer, Walter F

2006-01-01

A comprehensive analysis of the TP53 gene and its protein status was carried out on a panel of 56 colorectal cancer cell lines. This analysis was based on a combination of denaturing HPLC mutation screening of all exons of the p53 gene, sequencing the cDNA, and assessing the function of the p53 p...

TP53 mutations, human papilloma virus DNA and inflammation markers in esophageal squamous cell carcinoma from the Rift Valley, a high-incidence area in Kenya

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Martel-Planche Ghislaine

2011-10-01

Full Text Available Abstract Background Squamous Cell Carcinoma of Esophagus is one of the most common malignancies in both men and women in eastern and south-eastern Africa. In Kenya, clinical observations suggest that this cancer is frequent in the Rift Valley area. However, so far, there has been no report on the molecular characteristics of esophageal squamous cell carcinoma (ESCC in this area. Results We have analyzed TP53 mutations, the presence of human papilloma virus (HPV DNA and expression of inflammation markers Cyclooxygenase 2 (Cox-2 and Nitrotyrosine (NTyR in 28 cases (13 males and 15 females of archived ESCC tissues collected at the Moi Teaching and Referral Hospital in Eldoret, Kenya. Eleven mutations were detected in TP53 exons 5 to 8 (39%. All ESCC samples were negative for HPV 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73 and 82. Immunohistochemical analysis of Cox-2 and NTyR showed a low proportion of positive cases (17.4% and 39.1%, respectively. No association between the above markers and suspected risk factors (alcohol or tobacco use, hot tea drinking, use of charcoal for cooking was found. Conclusion Our findings suggest that mechanisms of esophageal carcinogenesis in eastern Africa might be different from other parts of the world. Low prevalence of TP53 mutation compared with other intermediate or high incidence areas of the world highlights this hypothesis. Our data did not support a possible ole of HPV in this series of cases. Further studies are needed to assess and compare the molecular patterns of ESCC from Kenya with those of high-incidence areas such as China or Central Asia.

Adrenocortical carcinoma with extension to the inferior vena cava and right atrium: 20-month-old girl with TP53 mutation

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Terry L. Levin, MD

2015-01-01

Full Text Available A 20-month-old female presented with respiratory distress and a right adrenal mass extending into the inferior vena cava and right atrium. The mass was initially thought to be neuroblastoma. Pathology later revealed adrenocortical carcinoma. Inferior vena cava extension is far more common in adrenocortical carcinoma than neuroblastoma, and its presence should prompt clinical and laboratory evaluation for an adrenocortical tumor. The genetic findings in TP53 associated with this disease are discussed.

Mutations in the TP53 gene affected recruitment of 53BP1 protein to DNA lesions, but level of 53BP1 was stable after gamma-irradiation that depleted MDC1 protein in specific TP53 mutants

Czech Academy of Sciences Publication Activity Database

Suchánková, Jana; Legartová, Soňa; Růčková, E.; Vojtešek, B.; Kozubek, Stanislav; Bártová, Eva

2017-01-01

Roč. 148, č. 3 (2017), s. 239-255 ISSN 0948-6143 R&D Projects: GA ČR GBP302/12/G157; GA MŠk 7F14369 Institutional support: RVO:68081707 Keywords : p53 tumor-suppressor * double-strand breaks * nuclear topography Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 2.553, year: 2016

Selective translational repression of truncated proteins from frameshift mutation-derived mRNAs in tumors.

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Kwon Tae You

2007-05-01

Full Text Available Frameshift and nonsense mutations are common in tumors with microsatellite instability, and mRNAs from these mutated genes have premature termination codons (PTCs. Abnormal mRNAs containing PTCs are normally degraded by the nonsense-mediated mRNA decay (NMD system. However, PTCs located within 50-55 nucleotides of the last exon-exon junction are not recognized by NMD (NMD-irrelevant, and some PTC-containing mRNAs can escape from the NMD system (NMD-escape. We investigated protein expression from NMD-irrelevant and NMD-escape PTC-containing mRNAs by Western blotting and transfection assays. We demonstrated that transfection of NMD-irrelevant PTC-containing genomic DNA of MARCKS generates truncated protein. In contrast, NMD-escape PTC-containing versions of hMSH3 and TGFBR2 generate normal levels of mRNA, but do not generate detectable levels of protein. Transfection of NMD-escape mutant TGFBR2 genomic DNA failed to generate expression of truncated proteins, whereas transfection of wild-type TGFBR2 genomic DNA or mutant PTC-containing TGFBR2 cDNA generated expression of wild-type protein and truncated protein, respectively. Our findings suggest a novel mechanism of gene expression regulation for PTC-containing mRNAs in which the deleterious transcripts are regulated either by NMD or translational repression.

A novel ELISA using a recombinant outer membrane protein, rTp0663, as the antigen for serological diagnosis of syphilis.

Science.gov (United States)

Xu, Man; Xie, Yafeng; Jiang, Chuanhao; Xiao, Yongjian; Kuang, Xingxing; Zhao, Feijun; Zeng, Tiebing; Liu, Shuangquan; Liang, Mingxing; Li, Li; Wang, Chuan; Wu, Yimou

2016-02-01

The lack of Treponema pallidum-specific antigens with highly accurate diagnosis makes the diagnosis of syphilis challenging. A soluble recombinant version of a new diagnostic protein Tp0663 has been produced. The serodiagnostic potential of this protein was assessed by screening 3326 serum samples simultaneously evaluated by rapid plasma reagin and T. pallidum particle agglutination tests. Kappa (κ) coefficients were used to compare the concordance between clinical diagnosis and the Tp0663-based ELISA or the ARCHITECT Syphilis TP chemiluminescent immunoassay (Abbott GmbH and Co. KG). Using the results of clinical diagnosis as the gold standard, the sensitivity and specificity of Tp0663 were found to be 98.83% (95% confidence interval (CI) 96.61-99.60%) and 100% (95% CI 99.88-100%), respectively. In comparison, the ARCHITECT Syphilis TP assay was found to have a lower sensitivity (97.27%, 95% CI 94.46-98.67%) and specificity (99.61%, 95% CI 99.32-99.78%). In particular, the ARCHITECT Syphilis TP exhibited a false-positive rate of 0.39%. Moreover, the ELISA was in perfect agreement with the gold standard, with a κ value of 0.99, comparable to that of ARCHITECT Syphilis TP (0.96). These results identified Tp0663 as a novel serodiagnostic candidate with great potential for developing novel tests for the diagnosis of syphilis. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Specific TP53 Mutants Overrepresented in Ovarian Cancer Impact CNV, TP53 Activity, Responses to Nutlin-3a, and Cell Survival

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Lisa K. Mullany

2015-10-01

Full Text Available Evolutionary Action analyses of The Cancer Gene Atlas data sets show that many specific p53 missense and gain-of-function mutations are selectively overrepresented and functional in high-grade serous ovarian cancer (HGSC. As homozygous alleles, p53 mutants are differentially associated with specific loss of heterozygosity (R273; chromosome 17; copy number variation (R175H; chromosome 9; and up-stream, cancer-related regulatory pathways. The expression of immune-related cytokines was selectively related to p53 status, showing for the first time that specific p53 mutants impact, and are related to, the immune subtype of ovarian cancer. Although the majority (31% of HGSCs exhibit loss of heterozygosity, a significant number (24% maintain a wild-type (WT allele and represent another HGSC subtype that is not well defined. Using human and mouse cell lines, we show that specific p53 mutants differentially alter endogenous WT p53 activity; target gene expression; and responses to nutlin-3a, a small molecular that activates WT p53 leading to apoptosis, providing “proof of principle” that ovarian cancer cells expressing WT and mutant alleles represent a distinct ovarian cancer subtype. We also show that siRNA knock down of endogenous p53 in cells expressing homozygous mutant alleles causes apoptosis, whereas cells expressing WT p53 (or are heterozygous for WT and mutant p53 alleles are highly resistant. Therefore, despite different gene regulatory pathways associated with specific p53 mutants, silencing mutant p53 might be a suitable, powerful, global strategy for blocking ovarian cancer growth in those tumors that rely on mutant p53 functions for survival. Knowing p53 mutational status in HGSC should permit new strategies tailored to control this disease.

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

International Nuclear Information System (INIS)

Tang, Yanan; Li, Liang

2013-01-01

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. • 12 C 2 -Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released 12 C 2 -dansyl labeled N-terminal amino acid was quantified using 13 C 2 -dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards

Comprehensive analysis of BRCA1, BRCA2 and TP53 germline mutation and tumor characterization: a portrait of early-onset breast cancer in Brazil.

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Dirce Maria Carraro

Full Text Available Germline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22% [7 in BRCA1 (13%, 4 in BRCA2 (7% and one in TP53 (2% gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes. Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients.

Natural products induce a G protein-mediated calcium pathway activating p53 in cancer cells

Energy Technology Data Exchange (ETDEWEB)

Ginkel, Paul R. van; Yan, Michael B. [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Bhattacharya, Saswati [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Department of Pediatrics, University of Wisconsin, Madison, WI 53792 (United States); Polans, Arthur S., E-mail: aspolans@wisc.edu [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Kenealey, Jason D. [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602 (United States)

2015-11-01

Paclitaxel, etoposide, vincristine and doxorubicin are examples of natural products being used as chemotherapeutics but with adverse side effects that limit their therapeutic window. Natural products derived from plants and having low toxicity, such as quercetin, resveratrol, epigallocatechin gallate and piceatannol, have been shown to inhibit tumor cell growth both in vitro and in pre-clinical models of cancer, but their mechanisms of action have not been fully elucidated, thus restricting their use as prototypes for developing synthetic analogs with improved anti-cancer properties. We and others have demonstrated that one of the earliest and consistent events upon exposure of tumor cells to these less toxic natural products is a rise in cytoplasmic calcium, activating several pro-apoptotic pathways. We describe here a G protein/inositol 1,4,5-trisphosphate pathway (InsP3) in MDA-MB-231 human breast cancer cells that mediates between these less toxic natural products and the release of calcium from the endoplasmic reticulum. Further, we demonstrate that this elevation of intracellular calcium modulates p53 activity and the subsequent transcription of several pro-apoptotic genes encoding PIG8, CD95, PIDD, TP53INP, RRM2B, Noxa, p21 and PUMA. We conclude from our findings that less toxic natural products likely bind to a G protein coupled receptor that activates a G protein-mediated and calcium-dependent pathway resulting selectively in tumor cell death. - Highlights: • Natural products having low toxicity increase cytoplasmic calcium in cancer cells. • A G-protein/IP{sub 3} pathway mediates the release of calcium from the ER. • The elevation of intracellular calcium modulates p53 activity. • p53 and other Ca{sup 2+}-dependent pro-apoptotic pathways inhibit cancer cell growth.

Natural products induce a G protein-mediated calcium pathway activating p53 in cancer cells

International Nuclear Information System (INIS)

Ginkel, Paul R. van; Yan, Michael B.; Bhattacharya, Saswati; Polans, Arthur S.; Kenealey, Jason D.

2015-01-01

Paclitaxel, etoposide, vincristine and doxorubicin are examples of natural products being used as chemotherapeutics but with adverse side effects that limit their therapeutic window. Natural products derived from plants and having low toxicity, such as quercetin, resveratrol, epigallocatechin gallate and piceatannol, have been shown to inhibit tumor cell growth both in vitro and in pre-clinical models of cancer, but their mechanisms of action have not been fully elucidated, thus restricting their use as prototypes for developing synthetic analogs with improved anti-cancer properties. We and others have demonstrated that one of the earliest and consistent events upon exposure of tumor cells to these less toxic natural products is a rise in cytoplasmic calcium, activating several pro-apoptotic pathways. We describe here a G protein/inositol 1,4,5-trisphosphate pathway (InsP3) in MDA-MB-231 human breast cancer cells that mediates between these less toxic natural products and the release of calcium from the endoplasmic reticulum. Further, we demonstrate that this elevation of intracellular calcium modulates p53 activity and the subsequent transcription of several pro-apoptotic genes encoding PIG8, CD95, PIDD, TP53INP, RRM2B, Noxa, p21 and PUMA. We conclude from our findings that less toxic natural products likely bind to a G protein coupled receptor that activates a G protein-mediated and calcium-dependent pathway resulting selectively in tumor cell death. - Highlights: • Natural products having low toxicity increase cytoplasmic calcium in cancer cells. • A G-protein/IP 3 pathway mediates the release of calcium from the ER. • The elevation of intracellular calcium modulates p53 activity. • p53 and other Ca 2+ -dependent pro-apoptotic pathways inhibit cancer cell growth.

Differential expression of ID4 and its association with TP53 mutation, SOX2, SOX4 and OCT-4 expression levels.

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Thais Fernanda de Almeida Galatro

Full Text Available Inhibitor of DNA Binding 4 (ID4 is a member of the helix-loop-helix ID family of transcription factors, mostly present in the central nervous system during embryonic development, that has been associated with TP53 mutation and activation of SOX2. Along with other transcription factors, ID4 has been implicated in the tumorigenic process of astrocytomas, contributing to cell dedifferentiation, proliferation and chemoresistance. In this study, we aimed to characterize the ID4 expression pattern in human diffusely infiltrative astrocytomas of World Health Organization (WHO grades II to IV of malignancy (AGII-AGIV; to correlate its expression level to that of SOX2, SOX4, OCT-4 and NANOG, along with TP53 mutational status; and to correlate the results with the clinical end-point of overall survival among glioblastoma patients. Quantitative real time PCR (qRT-PCR was performed in 130 samples of astrocytomas for relative expression, showing up-regulation of all transcription factors in tumor cases. Positive correlation was found when comparing ID4 relative expression of infiltrative astrocytomas with SOX2 (r = 0.50; p<0.005, SOX4 (r = 0.43; p<0.005 and OCT-4 (r = 0.39; p<0.05. The results from TP53 coding exon analysis allowed comparisons between wild-type and mutated status only in AGII cases, demonstrating significantly higher levels of ID4, SOX2 and SOX4 in mutated cases (p<0.05. This pattern was maintained in secondary GBM and further confirmed by immunohistochemistry, suggesting a role for ID4, SOX2 and SOX4 in early astrocytoma tumorigenesis. Combined hyperexpression of ID4, SOX4 and OCT-4 conferred a much lower (6 months median survival than did hypoexpression (18 months. Because both ID4 alone and a complex of SOX4 and OCT-4 activate SOX2 transcription, it is possible that multiple activation of SOX2 impair the prognosis of GBM patients. These observational results of associated expression of ID4 with SOX4 and OCT-4 may be used as a

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

Energy Technology Data Exchange (ETDEWEB)

Tang, Yanan; Li, Liang, E-mail: Liang.Li@ualberta.ca

2013-08-20

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. •{sup 12}C{sub 2}-Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released {sup 12}C{sub 2}-dansyl labeled N-terminal amino acid was quantified using {sup 13}C{sub 2}-dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

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C.Y. Nishikawa

2012-02-01

Full Text Available Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ54 co-factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL. A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH4Cl but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

Energy Technology Data Exchange (ETDEWEB)

Nishikawa, C.Y.; Araújo, L.M.; Kadowaki, M.A.S.; Monteiro, R.A.; Steffens, M.B.R.; Pedrosa, F.O.; Souza, E.M.; Chubatsu, L.S. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil)

2012-01-27

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ{sup 54} factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH{sub 4}Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense.

Science.gov (United States)

Nishikawa, C Y; Araújo, L M; Kadowaki, M A S; Monteiro, R A; Steffens, M B R; Pedrosa, F O; Souza, E M; Chubatsu, L S

2012-02-01

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ(54) co-factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH(4)Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

International Nuclear Information System (INIS)

Nishikawa, C.Y.; Araújo, L.M.; Kadowaki, M.A.S.; Monteiro, R.A.; Steffens, M.B.R.; Pedrosa, F.O.; Souza, E.M.; Chubatsu, L.S.

2012-01-01

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ 54 factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH 4 Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription

Fluorescence in situ hybridization of TP53 for the detection of chromosome 17 abnormalities in myelodysplastic syndromes.

Science.gov (United States)

Sánchez-Castro, Judit; Marco-Betés, Víctor; Gómez-Arbonés, Xavier; García-Cerecedo, Tomás; López, Ricard; Talavera, Elisabeth; Fernández-Ruiz, Sara; Ademà, Vera; Marugan, Isabel; Luño, Elisa; Sanzo, Carmen; Vallespí, Teresa; Arenillas, Leonor; Marco Buades, Josefa; Batlle, Ana; Buño, Ismael; Martín Ramos, María Luisa; Blázquez Rios, Beatriz; Collado Nieto, Rosa; Vargas, Ma Teresa; González Martínez, Teresa; Sanz, Guillermo; Solé, Francesc

2015-01-01

Conventional G-banding cytogenetics (CC) detects chromosome 17 (chr17) abnormalities in 2% of patients with de novo myelodysplastic syndromes (MDS). We used CC and fluorescence in situ hybridization (FISH) (LSI p53/17p13.1) to assess deletion of 17p in 531 patients with de novo MDS from the Spanish Group of Hematological Cytogenetics. FISH detected - 17 or 17p abnormalities in 13 cases (2.6%) in whom no 17p abnormalities were revealed by CC: 0.9% of patients with a normal karyotype, 0% in non-informative cytogenetics, 50% of patients with a chr17 abnormality without loss of 17p and 4.7% of cases with an abnormal karyotype not involving chr17. Our results suggest that applying FISH of 17p13 to identify the number of copies of the TP53 gene could be beneficial in patients with a complex karyotype. We recommend using FISH of 17p13 in young patients with a normal karyotype or non-informative cytogenetics, and always in isolated del(17p).

Maltose binding protein-fusion enhances the bioactivity of truncated forms of pig myostatin propeptide produced in E. coli.

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Sang Beum Lee

Full Text Available Myostatin (MSTN is a potent negative regulator of skeletal muscle growth. MSTN propeptide (MSTNpro inhibits MSTN binding to its receptor through complex formation with MSTN, implying that MSTNpro can be a useful agent to improve skeletal muscle growth in meat-producing animals. Four different truncated forms of pig MSTNpro containing N-terminal maltose binding protein (MBP as a fusion partner were expressed in E. coli, and purified by the combination of affinity chromatography and gel filtration. The MSTN-inhibitory capacities of these proteins were examined in an in vitro gene reporter assay. A MBP-fused, truncated MSTNpro containing residues 42-175 (MBP-Pro42-175 exhibited the same MSTN-inhibitory potency as the full sequence MSTNpro. Truncated MSTNpro proteins containing either residues 42-115 (MBP-Pro42-115 or 42-98 (MBP-Pro42-98 also exhibited MSTN-inhibitory capacity even though the potencies were significantly lower than that of full sequence MSTNpro. In pull-down assays, MBP-Pro42-175, MBP-Pro42-115, and MBP-Pro42-98 demonstrated their binding to MSTN. MBP was removed from the truncated MSTNpro proteins by incubation with factor Xa to examine the potential role of MBP on MSTN-inhibitory capacity of those proteins. Removal of MBP from MBP-Pro42-175 and MBP-Pro42-98 resulted in 20-fold decrease in MSTN-inhibitory capacity of Pro42-175 and abolition of MSTN-inhibitory capacity of Pro42-98, indicating that MBP as fusion partner enhanced the MSTN-inhibitory capacity of those truncated MSTNpro proteins. In summary, this study shows that MBP is a very useful fusion partner in enhancing MSTN-inhibitory potency of truncated forms of MSTNpro proteins, and MBP-fused pig MSTNpro consisting of amino acid residues 42-175 is sufficient to maintain the full MSTN-inhibitory capacity.

DNA impedance biosensor for detection of cancer, TP53 gene mutation, based on gold nanoparticles/aligned carbon nanotubes modified electrode.

Science.gov (United States)

Fayazfar, H; Afshar, A; Dolati, M; Dolati, A

2014-07-11

For the first time, a new platform based on electrochemical growth of Au nanoparticles on aligned multi-walled carbon nanotubes (A-MWCNT) was developed for sensitive lable-free DNA detection of the TP53 gene mutation, one of the most popular genes in cancer research. Electrochemical impedance spectroscopy (EIS) was used to monitor the sequence-specific DNA hybridization events related to TP53 gene. Compared to the bare Ta or MWCNT/Ta electrodes, the synergistic interactions of vertically aligned MWCNT array and gold nanoparticles at modified electrode could improve the density of the probe DNA attachment and resulting the sensitivity of the DNA sensor greatly. Using EIS, over the extended DNA concentration range, the change of charge transfer resistance was found to have a linear relationship in respect to the logarithm of the complementary oligonucleotides sequence concentrations in the wide range of 1.0×10(-15)-1.0×10(-7)M, with a detection limit of 1.0×10(-17)M (S/N=3). The prepared sensor also showed good stability (14 days), reproducibility (RSD=2.1%) and could be conveniently regenerated via dehybridization in hot water. The significant improvement in sensitivity illustrates that combining gold nanoparticles with the on-site fabricated aligned MWCNT array represents a promising platform for achieving sensitive biosensor for fast mutation screening related to most human cancer types. Copyright © 2014. Published by Elsevier B.V.

Evaluation of Tp-e interval and Tp-e/QT ratio in patients with ankylosing spondylitis.

Science.gov (United States)

Acar, Gurkan; Yorgun, Hikmet; Inci, Mehmet Fatih; Akkoyun, Murat; Bakan, Betul; Nacar, Alper Bugra; Dirnak, Imran; Cetin, Gozde Yildirim; Bozoglan, Orhan

2014-03-01

Ankylosing spondylitis (AS) is a chronic multi-systemic inflammatory rheumatic disorder. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate ventricular repolarization by using Tp-e interval and Tp-e/QT ratio in patients with AS, and to assess the relation with inflammation. Sixty-two patients with AS and 50 controls were included. Tp-e interval and Tp-e/QT ratio were measured from a 12-lead electrocardiogram, and the Tp-e interval corrected for heart rate. The plasma level of high sensitive C-reactive protein (hsCRP) was measured. These parameters were compared between groups. In electrocardiographic parameters analysis, QT dispersion (QTd) and corrected QTd were significantly increased in AS patients compared to the controls (31.7 ± 9.6 vs 28.2 ± 7.4 and 35.8 ± 11.5 vs 30.6 ± 7.9 ms, P = 0.03 and P = 0.007, respectively). cTp-e interval and Tp-e/QT ratio were also significantly higher in AS patients (92.1 ± 10.2 vs 75.8 ± 8.4 and 0.22 ± 0.02 vs 0.19 ± 0.02 ms, all P values ratio were significantly correlated with hsCRP (r = 0.63, P ratio were increased in AS patients. These electrocardiographic ventricular repolarization indexes were significantly correlated with the plasma level of hsCRP.

Screening for germline BRCA1, BRCA2, TP53 and CHEK2 mutations in families at-risk for hereditary breast cancer identified in a population-based study from Southern Brazil

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Edenir Inêz Palmero

2016-01-01

Full Text Available Abstract In Brazil, breast cancer is a public health care problem due to its high incidence and mortality rates. In this study, we investigated the prevalence of hereditary breast cancer syndromes (HBCS in a population-based cohort in Brazils southernmost capital, Porto Alegre. All participants answered a questionnaire about family history (FH of breast, ovarian and colorectal cancer and those with a positive FH were invited for genetic cancer risk assessment (GCRA. If pedigree analysis was suggestive of HBCS, genetic testing of the BRCA1, BRCA2, TP53, and CHEK2 genes was offered. Of 902 women submitted to GCRA, 214 had pedigrees suggestive of HBCS. Fifty of them underwent genetic testing: 18 and 40 for BRCA1/BRCA2 and TP53 mutation screening, respectively, and 7 for CHEK2 1100delC testing. A deleterious BRCA2 mutation was identified in one of the HBOC probands and the CHEK2 1100delC mutation occurred in one of the HBCC families. No deleterious germline alterations were identified in BRCA1 or TP53. Although strict inclusion criteria and a comprehensive testing approach were used, the suspected genetic risk in these families remains unexplained. Further studies in a larger cohort are necessary to better understand the genetic component of hereditary breast cancer in Southern Brazil.

[Evaluation of the Recombinant Protein Tp0965 of Treponema Pallidum as Perspective Antigen for the Improved Serological Diagnosis of Syphilis].

Science.gov (United States)

Runina, A V; Starovoitova, A S; Deryabin, D G; Kubanov, A A

2016-01-01

BACKGRAUND. Treponemal tests based on the detection of antibodies against the Treponema pallidum antigens are the most specific methods for serological diagnosis of syphilis. Due to the inability to cultivate this bacterium in vitro, the most promising sources of antigens for diagnostics are recombinant proteins of T. pallidum. Evaluation of the analytical value of certain T. pallidum proteins is the approach to improve sensitivity, specificity, and reproducibility of syphilis serological tests, including possibilities of differential diagnosis of various forms of the disease. The aim of the research was to evaluate the analytical values (sensitivity and specificity) of recombinant protein Tp0965 of T. pallidum as a candidate antigen for serological diagnosis of syphilis. tp0965 gene was cloned into the expression vector pET28a and the construct was used for the transformation of E. coli BL-21 (DE3) cells and further expression and purification of the recombinant protein. The collected protein was used as T. pallidum antigen for serum analysis (ELISA) of groups of patients with various forms of syphilis (n=84) and the group of healthy donors (n = 25). High frequency of positive ELISA results was shown with serum of patients with syphilis, compared to the group of healthy donors. The sensitivity of serological reactions using recombinant protein Tp0965 was 98.8%, specificity--87.5%. The highest sensitivity (100%) was detected in the groups of patients with primary, secondary and early latent syphilis while in the group of patients with late latent syphilis it decreased to 95.2%. We concluded that due to its specificity T. pallidum recombinant protein Tp0965 can be used as a novel perspective antigen for development of syphilis serological diagnostic assays (for primary and early latent forms).

Gastric Medullary Carcinoma with Sporadic Mismatch Repair Deficiency and a TP53 R273C Mutation: An Unusual Case with Wild-Type BRAF

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Brett M. Lowenthal

2017-01-01

Full Text Available Medullary carcinoma has long been recognized as a subtype of colorectal cancer associated with microsatellite instability and Lynch syndrome. Gastric medullary carcinoma is a very rare neoplasm. We report a 67-year-old male who presented with a solitary gastric mass. Total gastrectomy revealed a well-demarcated, poorly differentiated carcinoma with an organoid growth pattern, pushing borders, and abundant peritumoral lymphocytic response. The prior cytology was cellular with immunohistochemical panel consistent with upper gastrointestinal/pancreaticobiliary origin. Overall, the histopathologic findings were consistent with gastric medullary carcinoma. A mismatch repair panel revealed a mismatch repair protein deficient tumor with loss of MLH1 and PMS2 expression. BRAF V600E immunostain (VE1 and BRAF molecular testing were negative, indicating a wild-type gene. Tumor sequencing of MLH1 demonstrated a wild-type gene, while our molecular panel identified TP53 c.817C>T (p.R273C mutation. These findings were compatible with a sporadic tumor. Given that morphologically identical medullary tumors often occur in Lynch syndrome, it is possible that mismatch repair loss is an early event in sporadic tumors with p53 mutation being a late event. Despite having wild-type BRAF, this tumor is sporadic and unrelated to Lynch syndrome. This case report demonstrates that coordinate ancillary studies are needed to resolve sporadic versus hereditary rare tumors.

No evidence that protein truncating variants in BRIP1 are associated with breast cancer risk

DEFF Research Database (Denmark)

Easton, Douglas F; Lesueur, Fabienne; Decker, Brennan

2016-01-01

BACKGROUND: BRCA1 interacting protein C-terminal helicase 1 (BRIP1) is one of the Fanconi Anaemia Complementation (FANC) group family of DNA repair proteins. Biallelic mutations in BRIP1 are responsible for FANC group J, and previous studies have also suggested that rare protein truncating variants...

Discrimination of p53 immunohistochemistry-positive tumors by its staining pattern in gastric cancer

International Nuclear Information System (INIS)

Ando, Koji; Oki, Eiji; Saeki, Hiroshi; Yan, Zhao; Tsuda, Yasuo; Hidaka, Gen; Kasagi, Yuta; Otsu, Hajime; Kawano, Hiroyuki; Kitao, Hiroyuki; Morita, Masaru; Maehara, Yoshihiko

2015-01-01

Immunohistochemistry staining of p53 is a cheap and simple method to detect aberrant function of p53. However, there are some discrepancies between the result of immunohistochemistry staining and mutation analysis. This study attempted to find a new definition of p53 staining by its staining pattern. Immunohistochemistry staining of p53 and TP53 gene mutation analysis were performed in 148 gastric cancer patients. Also SNP-CGH array analysis was conducted to four cases. Positive staining of p53 was observed in 88 (59.5%) tumors. Tumors with positive p53 staining showed malignant features compared to negative tumors. Mutation of TP53 gene was observed in 29 (19.6%) tumors with higher age and differentiated type. In positive p53 tumors, two types could be distinguished; aberrant type and scattered type. With comparison to TP53 gene mutation analysis, all the scattered type had wild-type TP53 gene (P = 0.0003). SNP-CGH array showed that scattered-type tumors had no change in the structure of chromosome 17. P53-scattered-type staining tumors may reflect a functionally active nonmutated TP53 gene. In interpretation of p53 immunohistochemistry staining, distinguishing p53-positive tumors by their staining pattern may be important in gastric cancer

Formation of truncated proteins and high-molecular-mass aggregates upon soft illumination of photosynthetic proteins

DEFF Research Database (Denmark)

Rinalducci, Sara; Campostrini, Natascia; Antonioli, Paolo

2005-01-01

Different spot profiles were observed in 2D gel electrophoresis of thylakoid membranes performed either under complete darkness or by leaving the sample for a short time to low visible light. In the latter case, a large number of new spots with lower molecular masses, ranging between 15,000 and 25......,000 Da, were observed, and high-molecular-mass aggregates, seen as a smearing in the upper part of the gel, appeared in the region around 250 kDa. Identification of protein(s) contained in these new spots by MS/MS revealed that most of them are simply truncated proteins deriving from native ones...

Heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.

Science.gov (United States)

Patel, Kashyap A; Kettunen, Jarno; Laakso, Markku; Stančáková, Alena; Laver, Thomas W; Colclough, Kevin; Johnson, Matthew B; Abramowicz, Marc; Groop, Leif; Miettinen, Päivi J; Shepherd, Maggie H; Flanagan, Sarah E; Ellard, Sian; Inagaki, Nobuya; Hattersley, Andrew T; Tuomi, Tiinamaija; Cnop, Miriam; Weedon, Michael N

2017-10-12

Finding new causes of monogenic diabetes helps understand glycaemic regulation in humans. To find novel genetic causes of maturity-onset diabetes of the young (MODY), we sequenced MODY cases with unknown aetiology and compared variant frequencies to large public databases. From 36 European patients, we identify two probands with novel RFX6 heterozygous nonsense variants. RFX6 protein truncating variants are enriched in the MODY discovery cohort compared to the European control population within ExAC (odds ratio = 131, P = 1 × 10 -4 ). We find similar results in non-Finnish European (n = 348, odds ratio = 43, P = 5 × 10 -5 ) and Finnish (n = 80, odds ratio = 22, P = 1 × 10 -6 ) replication cohorts. RFX6 heterozygotes have reduced penetrance of diabetes compared to common HNF1A and HNF4A-MODY mutations (27, 70 and 55% at 25 years of age, respectively). The hyperglycaemia results from beta-cell dysfunction and is associated with lower fasting and stimulated gastric inhibitory polypeptide (GIP) levels. Our study demonstrates that heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.Maturity-onset diabetes of the young (MODY) is the most common subtype of familial diabetes. Here, Patel et al. use targeted DNA sequencing of MODY patients and large-scale publically available data to show that RFX6 heterozygous protein truncating variants cause reduced penetrance MODY.

Truncation of the C-terminal region of Toscana Virus NSs protein is critical for interferon-β antagonism and protein stability.

Science.gov (United States)

Gori Savellini, Gianni; Gandolfo, Claudia; Cusi, Maria Grazia

2015-12-01

Toscana Virus (TOSV) is a Phlebovirus responsible for central nervous system (CNS) injury in humans. The TOSV non-structural protein (NSs), which interacting with RIG-I leads to its degradation, was analysed in the C terminus fragment in order to identify its functional domains. To this aim, two C-terminal truncated NSs proteins, Δ1C-NSs (aa 1-284) and Δ2C-NSs (aa 1-287) were tested. Only Δ1C-NSs did not present any inhibitory effect on RIG-I and it showed a greater stability than the whole NSs protein. Moreover, the deletion of the TLQ aa sequence interposed between the two ΔC constructs caused a greater accumulation of the protein with a weak inhibitory effect on RIG-I, indicating some involvement of these amino acids in the NSs activity. Nevertheless, all the truncated proteins were still able to interact with RIG-I, suggesting that the domains responsible for RIG-I signaling and RIG-I interaction are mapped on different regions of the protein. Copyright © 2015 Elsevier Inc. All rights reserved.

Integral analysis of p53 and its value as prognostic factor in sporadic colon cancer

International Nuclear Information System (INIS)

Fariña Sarasqueta, Arantza; Morreau, Hans; Forte, Giusi; Corver, Wim E; Miranda, Noel F de; Ruano, Dina; Eijk, Ronald van; Oosting, Jan; Tollenaar, Rob AEM; Wezel, Tom van

2013-01-01

p53 (encoded by TP53) is involved in DNA damage repair, cell cycle regulation, apoptosis, aging and cellular senescence. TP53 is mutated in around 50% of human cancers. Nevertheless, the consequences of p53 inactivation in colon cancer outcome remain unclear. Recently, a new role of p53 together with CSNK1A1 in colon cancer invasiveness has been described in mice. By combining data on different levels of p53 inactivation, we aimed to predict p53 functionality and to determine its effects on colon cancer outcome. Moreover, survival effects of CSNK1A1 together with p53 were also studied. Eighty-three formalin fixed paraffin embedded colon tumors were enriched for tumor cells using flow sorting, the extracted DNA was used in a custom SNP array to determine chr17p13-11 allelic state; p53 immunostaining, TP53 exons 5, 6, 7 and 8 mutations were determined in combination with mRNA expression analysis on frozen tissue. Patients with a predicted functional p53 had a better prognosis than patients with non functional p53 (Log Rank p=0.009). Expression of CSNK1A1 modified p53 survival effects. Patients with low CSNK1A1 expression and non-functional p53 had a very poor survival both in the univariate (Log Rank p<0.001) and in the multivariate survival analysis (HR=4.74 95% CI 1.45 – 15.3 p=0.009). The combination of mutational, genomic, protein and downstream transcriptional activity data predicted p53 functionality which is shown to have a prognostic effect on colon cancer patients. This effect was specifically modified by CSKN1A1 expression

TP508 accelerates fracture repair by promoting cell growth over cell death

International Nuclear Information System (INIS)

Li Xinmin; Wang Hali; Touma, Edward; Qi Yuchen; Rousseau, Emma; Quigg, Richard J.; Ryaby, James T.

2007-01-01

TP508 is a synthetic 23-amino acid peptide representing a receptor-binding domain of human thrombin. We have previously shown that a single injection of TP508 accelerates fracture healing in a rat femoral fracture model. To understand how TP508 acts at the protein level during fracture healing, we compared the translational profiles between saline-control and fractured femur at six time points after TP508 treatment using the second generation of BD Clontech TM Antibody Microarray. Here, we demonstrate that TP508 accelerates fracture healing by modulating expression levels of proteins primarily involved in the functional categories of cell cycle, cellular growth and proliferation, and cell death. The majority of those proteins are physically interrelated and functionally overlapped. The action of those proteins is highlighted by a central theme of promoting cell growth via balance of cell survival over cell death signals. This appears to occur through the stimulation of several bone healing pathways including cell cycle-G1/S checkpoint regulation, apoptosis, JAK/STAT, NF-κB, PDGF, PI3K/AKT, PTEN, and ERK/MAPK

A comparison among HER2, TP53, PAI-1, angiogenesis, and proliferation activity as prognostic variables in tumours from 408 patients diagnosed with early breast cancer

DEFF Research Database (Denmark)

Offersen, Birgitte Vrou; Alsner, Jan; Olsen, Karen Ege

2008-01-01

: Tumour sections were stained for HER2, CD34, and MIB-1. HER2 scores were based on staining intensity, 3+ being considered HER2+. Angiogenesis was scored by the Chalkley method. MIB-1 was evaluated using systematic random sampling. PAI-1 was measured by ELISA. TP53 mutations were evaluated by DGGE...

Immunohistochemical analysis of P53 protein in odontogenic cysts

Science.gov (United States)

Gaballah, Essam Taher M.A.; Tawfik, Mohamed A.

2010-01-01

The p53 is a well-known tumor suppressor gene, the mutations of which are closely related to the decreased differentiation of cells. Findings of studies on immunohistochemical P53 expression in odontogenic cysts are controversial. The present study was carried-out to investigate the immunohistochemical expression of P53 protein in odontogenic cysts. Thirty paraffin blocks of diagnosed odontogenic cysts were processed to determine the immunohistochemical expression of P53 protein. Nine of the 11 odontogenic keratocysts (81.8%) expressed P53, one of three dentigerous cyst cases expressed P53, while none of the 16 radicular cysts expressed P53 protein. The findings of the present work supported the reclassification of OKC as keratocystic odontogenic tumor. PMID:23960493

Molecular spectrum of KRAS, NRAS, BRAF, PIK3CA, TP53, and APC somatic gene mutations in Arab patients with colorectal cancer: determination of frequency and distribution pattern

Science.gov (United States)

Al-Shamsi, Humaid O.; Jones, Jeremy; Fahmawi, Yazan; Dahbour, Ibrahim; Tabash, Aziz; Abdel-Wahab, Reham; Abousamra, Ahmed O. S.; Shaw, Kenna R.; Xiao, Lianchun; Hassan, Manal M.; Kipp, Benjamin R.; Kopetz, Scott; Soliman, Amr S.; McWilliams, Robert R.; Wolff, Robert A.

2016-01-01

Background The frequency rates of mutations such as KRAS, NRAS, BRAF, and PIK3CA in colorectal cancer (CRC) differ among populations. The aim of this study was to assess mutation frequencies in the Arab population and determine their correlations with certain clinicopathological features. Methods Arab patients from the Arab Gulf region and a population of age- and sex-matched Western patients with CRC whose tumors were evaluated with next-generation sequencing (NGS) were identified and retrospectively reviewed. The mutation rates of KRAS, NRAS, BRAF, PIK3CA, TP53, and APC were recorded, along with clinicopathological features. Other somatic mutation and their rates were also identified. Fisher’s exact test was used to determine the association between mutation status and clinical features. Results A total of 198 cases were identified; 99 Arab patients and 99 Western patients. Fifty-two point seven percent of Arab patients had stage IV disease at initial presentation, 74.2% had left-sided tumors. Eighty-nine point two percent had tubular adenocarcinoma and 10.8% had mucinous adenocarcinoma. The prevalence rates of KRAS, NRAS, BRAF, PIK3CA, TP53, APC, SMAD, FBXW7 mutations in Arab population were 44.4%, 4%, 4%, 13.1%, 52.5%, 27.3%, 2% and 3% respectively. Compared to 48.4%, 4%, 4%, 12.1%, 47.5%, 24.2%, 11.1% and 0% respectively in matched Western population. Associations between these mutations and patient clinicopathological features were not statistically significant. Conclusions This is the first study to report comprehensive hotspot mutations using NGS in Arab patients with CRC. The frequency of KRAS, NRAS, BRAF, TP53, APC and PIK3CA mutations were similar to reported frequencies in Western population except SMAD4 that had a lower frequency and higher frequency of FBXW7 mutation. PMID:28078112

Neoplasias astrocitárias e correlação com as proteínas p53 mutada e Ki-67 Astrocytic neoplasms and correlation with mutate p53 and Ki-67 proteins

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Gustavo Rassier Isolan

2005-12-01

Full Text Available As neoplasias astrocitárias correspondem a 60% dos tumores do sistema nervoso central, sendo o estudo da biologia molecular um importante passo para a compreensão da gênese e comportamento biológico destas doenças. As proteínas Ki-67, que é um marcador de proliferação celular, e p53, que é o produto do gene supressor de tumor de mesmo nome, são importantes marcadores tumorais. O objetivo deste estudo foi identificar e quantificar as proteínas Ki-67 e produto do gene supressor de tumor TP53 em diferentes graus de malignidade das neoplasias astrocitárias, bem como analisar suas relações com idade e sexo. Foram estudadas por imuno-histoquímica as proteínas Ki-67 e p53 em 47 pacientes com neoplasias astrocitárias ressecadas cirurgicamente, classificadas previamente e revisadas quanto ao grau de malignidade, de acordo com o proposto pela Organização Mundial da Saúde. Os núcleos celulares imunomarcados foram quantificados no programa Imagelab-softium pela razão paramétrica absoluta entre os núcleos de células positivas e o número total de células tumorais, sendo contadas 1000 células. O delineamento utilizado foi transversal não controlado. Para análise estatística as variáveis foram divididas em grupos, que para a Ki-67 foram ausente, 5% e para a p53 foram ausente (0, The astrocytic neoplasms respond by 60% of the central nervous system tumors, being the study of the molecular biology an important step for the understanding of the genesis and biological behavior of these diseases. The Ki-67 proteins, which are markers of the cellular proliferation, and p53, which is the product of the tumor suppressor gene TP53, are both important tumoral markers. This study intends to identify and quantify the Ki-67 and p53 proteins in astrocytic tumors of different grades of malignancy, as well as to analyze their relations with age and gender. Ki-67 and p53 proteins in 47 patients with surgically resected astrocytic neoplasms were

A truncated Kv1.1 protein in the brain of the megencephaly mouse: expression and interaction

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Århem Peter

2005-11-01

Full Text Available Abstract Background The megencephaly mouse, mceph/mceph, is epileptic and displays a dramatically increased brain volume and neuronal count. The responsible mutation was recently revealed to be an eleven base pair deletion, leading to a frame shift, in the gene encoding the potassium channel Kv1.1. The predicted MCEPH protein is truncated at amino acid 230 out of 495. Truncated proteins are usually not expressed since nonsense mRNAs are most often degraded. However, high Kv1.1 mRNA levels in mceph/mceph brain indicated that it escaped this control mechanism. Therefore, we hypothesized that the truncated Kv1.1 would be expressed and dysregulate other Kv1 subunits in the mceph/mceph mice. Results We found that the MCEPH protein is expressed in the brain of mceph/mceph mice. MCEPH was found to lack mature (Golgi glycosylation, but to be core glycosylated and trapped in the endoplasmic reticulum (ER. Interactions between MCEPH and other Kv1 subunits were studied in cell culture, Xenopus oocytes and the brain. MCEPH can form tetramers with Kv1.1 in cell culture and has a dominant negative effect on Kv1.2 and Kv1.3 currents in oocytes. However, it does not retain Kv1.2 in the ER of neurons. Conclusion The megencephaly mice express a truncated Kv1.1 in the brain, and constitute a unique tool to study Kv1.1 trafficking relevant for understanding epilepsy, ataxia and pathologic brain overgrowth.

Análisis genético en APC, KRAS y TP53 en pacientes con cáncer de estómago y colon

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K.A. Palacio-Rúa

2014-04-01

Conclusión: Las mutaciones en los genes APC, KRAS y TP53 fueron más comunes en el CCR que en el CE; nuestros resultados indican la existencia de diferentes vías genéticas en la carcinogénesis del CE y del CCR, y revelan una frecuencia de mutaciones particular en los pacientes colombianos estudiados, que podría estar influida por factores ambientales y étnicos, y el estilo de vida de esta población.

Expression of a truncated receptor protein tyrosine phosphatase kappa in the brain of an adult transgenic mouse

DEFF Research Database (Denmark)

Shen, P; Canoll, P D; Sap, J

1999-01-01

that goal, we have used this mouse model to map the distribution of the truncated RPTP-kappa/beta-geo fusion protein in the adult mouse brain using beta-galactosidase as a marker enzyme. Visualization of the beta-galactosidase activity revealed a non-random pattern of expression, and identified cells......-6596]. Nevertheless, since the transgene's expression is driven by the endogenous RPTP-kappa promoter, distribution of the truncated RPTP-kappa/beta-geo fusion protein should reflect the regional and cellular expression of wild-type RPTP-kappa, and thus may identify sites where RPTP-kappa is important. Towards...

N-terminally truncated GADD34 proteins are convenient translation enhancers in a human cell-derived in vitro protein synthesis system.

Science.gov (United States)

Mikami, Satoshi; Kobayashi, Tominari; Machida, Kodai; Masutani, Mamiko; Yokoyama, Shigeyuki; Imataka, Hiroaki

2010-07-01

Human cell-derived in vitro protein synthesis systems are useful for the production of recombinant proteins. Productivity can be increased by supplementation with GADD34, a protein that is difficult to express in and purify from E. coli. Deletion of the N-terminal 120 or 240 amino acids of GADD34 improves recovery of this protein from E. coli without compromising its ability to boost protein synthesis in an in vitro protein synthesis system. The use of N-terminally truncated GADD34 proteins in place of full-length GADD34 should improve the utility of human cell-based cell-free protein synthesis systems.

Biobibliometrics (UGDH-TP53-BRCA1) Genes Connections in the Possible Relationship Between Breast Cancer and EEG.

Science.gov (United States)

Martzoukos, Yannis; Papavlasopoulos, Sozon; Poulos, Marios; Syrrou, Maria

2017-01-01

In recent years there has been an increasingly amount of data stored in biomedical Databases due to the breakthroughs in biology and bioinformatics, biomedical information is growing exponentially making efficient information retrieval from scientist more and more challenging. New Scientific fields as Bioinformatics seem to be the tool needed to extract scientifically important data based on experimental results and information provided by papers and journals. In this paper we are going to implement a custom made IT system in order to find connections between genes in the breast cancer pathways such the BRCA1 with the electrical energy in the human brain with UGDH gene via the TP53 tumor gene. The proposed system will be able to identify the appearance of each gene ID and compare the coexistence of two genes in PubMed articles/papers. The final system could become a useful tool against the struggle of scientists and medical professionals in the near future.

The different radiation response and radiation-induced bystander effects in colorectal carcinoma cells differing in p53 status

International Nuclear Information System (INIS)

Widel, Maria; Lalik, Anna; Krzywon, Aleksandra; Poleszczuk, Jan; Fujarewicz, Krzysztof; Rzeszowska-Wolny, Joanna

2015-01-01

Highlights: • We tested radiation response and bystander effect on HCT116p53+/+ and p53−/− cells. • The p53+/+ cells developed premature senescence in exposed and bystander neighbors. • Directly exposed and bystander p53−/− cells died profoundly through apoptosis. • Interleukins 6 and 8 were differently generated by both cell lines. • NFκB path was activated mainly in p53+/+ hit cells, in p53 −/− in bystanders only. - Abstract: Radiation-induced bystander effect, appearing as different biological changes in cells that are not directly exposed to ionizing radiation but are under the influence of molecular signals secreted by irradiated neighbors, have recently attracted considerable interest due to their possible implication for radiotherapy. However, various cells present diverse radiosensitivity and bystander responses that depend, inter alia, on genetic status including TP53, the gene controlling the cell cycle, DNA repair and apoptosis. Here we compared the ionizing radiation and bystander responses of human colorectal carcinoma HCT116 cells with wild type or knockout TP53 using a transwell co-culture system. The viability of exposed to X-rays (0–8 Gy) and bystander cells of both lines showed a roughly comparable decline with increasing dose. The frequency of micronuclei was also comparable at lower doses but at higher increased considerably, especially in bystander TP53-/- cells. Moreover, the TP53-/- cells showed a significantly elevated frequency of apoptosis, while TP53+/+ counterparts expressed high level of senescence. The cross-matched experiments where irradiated cells of one line were co-cultured with non-irradiated cells of opposite line show that both cell lines were also able to induce bystander effects in their counterparts, however different endpoints revealed with different strength. Potential mediators of bystander effects, IL-6 and IL-8, were also generated differently in both lines. The knockout cells secreted IL-6 at

The different radiation response and radiation-induced bystander effects in colorectal carcinoma cells differing in p53 status

Energy Technology Data Exchange (ETDEWEB)

Widel, Maria, E-mail: maria.widel@polsl.pl [Biosystems Group, Institute of Automatic Control, Silesian University of Technology, 16 Akademicka Street, 44-100 Gliwice (Poland); Lalik, Anna; Krzywon, Aleksandra [Biosystems Group, Institute of Automatic Control, Silesian University of Technology, 16 Akademicka Street, 44-100 Gliwice (Poland); Poleszczuk, Jan [College of Inter-faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, 93 Zwirki i Wigury Street, 02-089 Warsaw (Poland); Department of Integrated Mathematical Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida (United States); Fujarewicz, Krzysztof; Rzeszowska-Wolny, Joanna [Biosystems Group, Institute of Automatic Control, Silesian University of Technology, 16 Akademicka Street, 44-100 Gliwice (Poland)

2015-08-15

Highlights: • We tested radiation response and bystander effect on HCT116p53+/+ and p53−/− cells. • The p53+/+ cells developed premature senescence in exposed and bystander neighbors. • Directly exposed and bystander p53−/− cells died profoundly through apoptosis. • Interleukins 6 and 8 were differently generated by both cell lines. • NFκB path was activated mainly in p53+/+ hit cells, in p53 −/− in bystanders only. - Abstract: Radiation-induced bystander effect, appearing as different biological changes in cells that are not directly exposed to ionizing radiation but are under the influence of molecular signals secreted by irradiated neighbors, have recently attracted considerable interest due to their possible implication for radiotherapy. However, various cells present diverse radiosensitivity and bystander responses that depend, inter alia, on genetic status including TP53, the gene controlling the cell cycle, DNA repair and apoptosis. Here we compared the ionizing radiation and bystander responses of human colorectal carcinoma HCT116 cells with wild type or knockout TP53 using a transwell co-culture system. The viability of exposed to X-rays (0–8 Gy) and bystander cells of both lines showed a roughly comparable decline with increasing dose. The frequency of micronuclei was also comparable at lower doses but at higher increased considerably, especially in bystander TP53-/- cells. Moreover, the TP53-/- cells showed a significantly elevated frequency of apoptosis, while TP53+/+ counterparts expressed high level of senescence. The cross-matched experiments where irradiated cells of one line were co-cultured with non-irradiated cells of opposite line show that both cell lines were also able to induce bystander effects in their counterparts, however different endpoints revealed with different strength. Potential mediators of bystander effects, IL-6 and IL-8, were also generated differently in both lines. The knockout cells secreted IL-6 at

The different radiation response and radiation-induced bystander effects in colorectal carcinoma cells differing in p53 status.

Science.gov (United States)

Widel, Maria; Lalik, Anna; Krzywon, Aleksandra; Poleszczuk, Jan; Fujarewicz, Krzysztof; Rzeszowska-Wolny, Joanna

2015-08-01

Radiation-induced bystander effect, appearing as different biological changes in cells that are not directly exposed to ionizing radiation but are under the influence of molecular signals secreted by irradiated neighbors, have recently attracted considerable interest due to their possible implication for radiotherapy. However, various cells present diverse radiosensitivity and bystander responses that depend, inter alia, on genetic status including TP53, the gene controlling the cell cycle, DNA repair and apoptosis. Here we compared the ionizing radiation and bystander responses of human colorectal carcinoma HCT116 cells with wild type or knockout TP53 using a transwell co-culture system. The viability of exposed to X-rays (0-8 Gy) and bystander cells of both lines showed a roughly comparable decline with increasing dose. The frequency of micronuclei was also comparable at lower doses but at higher increased considerably, especially in bystander TP53-/- cells. Moreover, the TP53-/- cells showed a significantly elevated frequency of apoptosis, while TP53+/+ counterparts expressed high level of senescence. The cross-matched experiments where irradiated cells of one line were co-cultured with non-irradiated cells of opposite line show that both cell lines were also able to induce bystander effects in their counterparts, however different endpoints revealed with different strength. Potential mediators of bystander effects, IL-6 and IL-8, were also generated differently in both lines. The knockout cells secreted IL-6 at lower doses whereas wild type cells only at higher doses. Secretion of IL-8 by TP53-/- control cells was many times lower than that by TP53+/+ but increased significantly after irradiation. Transcription of the NFκBIA was induced in irradiated TP53+/+ mainly, but in bystanders a higher level was observed in TP53-/- cells, suggesting that TP53 is required for induction of NFκB pathway after irradiation but another mechanism of activation must operate in

Prion Protein on Astrocytes or in Extracellular Fluid Impedes Neurodegeneration Induced by Truncated Prion Protein

OpenAIRE

Race, Brent; Meade-White, Kimberly; Race, Richard; Baumann, Frank; Aguzzi, Adriano; Chesebro, Bruce

2009-01-01

Prion protein (PrP) is a host-encoded membrane-anchored glycoprotein which is required for susceptibility to prion disease. PrP may also be important for normal brain functions such as hippocampal spatial memory. Previously transgenic mice expressing amino terminally truncated mouse PrP (Δ32–134) spontaneously developed a fatal disease associated with degeneration of cerebellar granular neurons as well as vacuolar degeneration of deep cerebellar and brain stem white matter. This disease could...

The novel fusion proteins, GnRH-p53 and GnRHIII-p53, expression and their anti-tumor effect.

Directory of Open Access Journals (Sweden)

Peiyuan Jia

Full Text Available p53, one of the most well studied tumor suppressor factor, is responsible to a variety of damage owing to the induction of apoptosis and cell cycle arrest in the tumor cells. More than 50% of human tumors contain mutation or deletion of p53. Gonadotrophin-releasing hormone (GnRH, as the ligand of Gonadotrophin-releasing hormone receptor (GnRH-R, was used to deliver p53 into tumor cells. The p53 fusion proteins GnRH-p53 and GnRH iii-p53 were expressed and their targeted anti-tumor effects were determined. GnRH mediates its fusion proteins transformation into cancer cells. The intracellular delivery of p53 fusion proteins exerted the inhibition of the growth of H1299 cells in vitro and the reduction of tumor volume in vivo. Their anti-tumor effect was functioned by the apoptosis and cell cycle arrest induced by p53. Hence, the fusion protein could be a novel protein drug for anti-tumor therapy.

Electrophoretic detection of protein p53 in human leukocytes

International Nuclear Information System (INIS)

Paponov, V.D.; Kupsik, E.G.; Shcheglova, E.G.; Yarullin, N.N.

1986-01-01

The authors have found an acid-soluble protein with mol. wt. of about 53 kD in peripheral blood leukocytes of persons with Down's syndrome. It was present in different quantities in all 20 patients tested, but was virtually not discovered in 12 healthy blood donors. This paper determines the possible identity of this protein with protein p53 from mouse ascites carcinoma by comparing their electrophoretic mobilities, because the accuracy of electrophoretic determination of the molecular weight of proteins is not sufficient to identify them. The paper also describes experiments to detect a protein with electrophoretic mobility identical with that of a protein in the leukocytes of patients with Down's syndrome in leukocytes of patients with leukemia. To discover if protein p53 is involved in cell proliferation, the protein composition of leukocytes from healthy blood donors, cultured in the presence and absence of phytohemagglutinin (PHA), was compared. Increased incorporation of H 3-thymidine by leukocytes of patients with Down's syndrome is explained by the presence of a population of immature leukocytes actively synthesizing DNA in the peripheral blood of these patients, and this can also explain the presence of protein p53 in the leukocytes of these patients

Knockout and transgenic mice of Trp53: what have we learned about p53 in breast cancer?

International Nuclear Information System (INIS)

Blackburn, Anneke C; Jerry, D Joseph

2002-01-01

The human p53 tumor suppressor gene TP53 is mutated at a high frequency in sporadic breast cancer, and Li-Fraumeni syndrome patients who carry germline mutations in one TP53 allele have a high incidence of breast cancer. In the 10 years since the first knockout of the mouse p53 tumor suppressor gene (designated Trp53) was published, much has been learned about the contribution of p53 to biology and tumor suppression in the breast through the use of p53 transgenic and knockout mice. The original mice deficient in p53 showed no mammary gland phenotype. However, studies using BALB/c-Trp53-deficient mice have demonstrated a delayed involution phenotype and a mammary tumor phenotype. Together with other studies of mutant p53 transgenes and p53 bitransgenics, a greater understanding has been gained of the role of p53 in involution, of the regulation of p53 activity by hormones, of the effect of mouse strain and modifier genes on tumor phenotype, and of the cooperation between p53 and other oncogenic pathways, chemical carcinogens and hormonal stimulation in mammary tumorigenesis. Both p53 transgenic and knockout mice are important in vivo tools for understanding breast cancer, and are yet to be exploited for developing therapeutic strategies in breast cancer

Cloning and sequencing of V genes from anti-osteosarcoma monoclonal antibodies TP-1 and TP-3: Location of lysine residues and implications for radiolabeling

International Nuclear Information System (INIS)

Olafsen, Tove; Bruland, Oeyvind S.; Zalutsky, Michael R.; Sandlie, Inger

1995-01-01

Monoclonal antibodies TP-1 and TP-3 are of potential utility for the radioimmunodiagnosis of osteosarcoma in both human and canine patients. The V genes of these antibodies were cloned and sequenced and to facilitate radiolabeling of these proteins, the location of the lysine residues within these sequences have been determined. The V-domains of TP-1 contain a total of 12 lysines, 10 in the framework region and 2 in the CDR region, while the V-domains of TP-3 contain a total of 14 lysines, 11 in the framework region and 3 in the CDR regions. Using space-filling models, the availability of each lysine residue for radiolabeling, and potential interference with antigen binding was predicted

Cloning and sequencing of V genes from anti-osteosarcoma monoclonal antibodies TP-1 and TP-3: Location of lysine residues and implications for radiolabeling

Energy Technology Data Exchange (ETDEWEB)

Olafsen, Tove; Bruland, Oeyvind S.; Zalutsky, Michael R.; Sandlie, Inger

1995-08-01

Monoclonal antibodies TP-1 and TP-3 are of potential utility for the radioimmunodiagnosis of osteosarcoma in both human and canine patients. The V genes of these antibodies were cloned and sequenced and to facilitate radiolabeling of these proteins, the location of the lysine residues within these sequences have been determined. The V-domains of TP-1 contain a total of 12 lysines, 10 in the framework region and 2 in the CDR region, while the V-domains of TP-3 contain a total of 14 lysines, 11 in the framework region and 3 in the CDR regions. Using space-filling models, the availability of each lysine residue for radiolabeling, and potential interference with antigen binding was predicted.

Short telomere length is associated with NOTCH1/SF3B1/TP53 aberrations and poor outcome in newly diagnosed chronic lymphocytic leukemia patients

DEFF Research Database (Denmark)

Mansouri, Larry; Grabowski, Pawel; Degerman, Sofie

2013-01-01

Most previous studies on telomere length (TL) in chronic lymphocytic leukemia (CLL) are based on referral cohorts including a high proportion of aggressive cases. Here, the impact of TL was analyzed in a population-based cohort of newly diagnosed CLL (n = 265) and in relation to other prognostic ...... markers. Short telomeres were particularly associated with high-risk genetic markers, such as NOTCH1, SF3B1, or TP53 aberrations, and predicted a short time to treatment (TTT) and overall survival (OS) (both P...

Prolonged Tp-e Interval, Tp-e/QT Ratio and Tp-e/QTc Ratio in Patients with Type 2 Diabetes Mellitus

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Alptug Tokatli

2016-03-01

Full Text Available BackgroundType 2 diabetes mellitus (T2DM is associated with increased risk of malignant ventricular arrhythmias. Cardiac electrical inhomogeneity may be the leading cause of the increased arrhythmic risk in patients with T2DM. The peak and the end of the T wave (Tp-e interval and associated Tp-e/QT ratio are promising measures of ventricular repolarization indicating transmural dispersion of repolarization. The aim of this study was to assess ventricular repolarization in patients with T2DM by using Tp-e interval, Tp-e/QT ratio and Tp-e/corrected QT interval (QTc ratio.MethodsForty-three patients with T2DM and 43 healthy control subjects, matched by gender and age, were studied. All participants underwent electrocardiography (ECG recording. PR, RR and QT intervals represents the ECG intervals. These are not abbreviations. In all literature these ECG intervals are written like in this text. Tp-e intervals were measured from 12-lead ECG. Rate QTc was calculated by using the Bazett's formula. Tp-e/QT ratio and Tp-e/QTc ratio were also calculated.ResultsMean Tp-e interval was significantly prolonged in patients with T2DM compared to controls (79.4±10.3, 66.4±8.1 ms, respectively; P<0.001. We also found significantly higher values of Tp-e/QT ratio and Tp-e/QTc ratio in patients with diabetes than controls (0.21±0.03, 0.17±0.02 and 0.19±0.02, 0.16±0.02, respectively; P<0.001. There was no difference in terms of the other ECG parameters between the groups.ConclusionTp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were prolonged in patients with T2DM. We concluded that T2DM leads to augmentation of transmural dispersion of repolarization suggesting increased risk for ventricular arrhythmogenesis.

Chronology of p53 protein accumulation in gastric carcinogenesis

NARCIS (Netherlands)

Craanen, M. E.; Blok, P.; Dekker, W.; Offerhaus, G. J.; Tytgat, G. N.

1995-01-01

p53 Protein accumulation in early gastric carcinoma was studied in relation to the histological type (Lauren classification) and the type of growth pattern, including the chronology of p53 protein accumulation during carcinogenesis. Forty five, paraffin embedded gastrectomy specimens from early

Combining Oncolytic Virotherapy with p53 Tumor Suppressor Gene Therapy

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Christian Bressy

2017-06-01

Full Text Available Oncolytic virus (OV therapy utilizes replication-competent viruses to kill cancer cells, leaving non-malignant cells unharmed. With the first U.S. Food and Drug Administration-approved OV, dozens of clinical trials ongoing, and an abundance of translational research in the field, OV therapy is poised to be one of the leading treatments for cancer. A number of recombinant OVs expressing a transgene for p53 (TP53 or another p53 family member (TP63 or TP73 were engineered with the goal of generating more potent OVs that function synergistically with host immunity and/or other therapies to reduce or eliminate tumor burden. Such transgenes have proven effective at improving OV therapies, and basic research has shown mechanisms of p53-mediated enhancement of OV therapy, provided optimized p53 transgenes, explored drug-OV combinational treatments, and challenged canonical roles for p53 in virus-host interactions and tumor suppression. This review summarizes studies combining p53 gene therapy with replication-competent OV therapy, reviews preclinical and clinical studies with replication-deficient gene therapy vectors expressing p53 transgene, examines how wild-type p53 and p53 modifications affect OV replication and anti-tumor effects of OV therapy, and explores future directions for rational design of OV therapy combined with p53 gene therapy.

Mutation analysis of genes that control the G1/S cell cycle in melanoma: TP53, CDKN1A, CDKN2A, and CDKN2B

International Nuclear Information System (INIS)

Soto, José Luis; Cabrera, Carmen M; Serrano, Salvio; López-Nevot, Miguel Ángel

2005-01-01

The role of genes involved in the control of progression from the G1 to the S phase of the cell cycle in melanoma tumors in not fully known. The aim of our study was to analyse mutations in TP53, CDKN1A, CDKN2A, and CDKN2B genes in melanoma tumors and melanoma cell lines We analysed 39 primary and metastatic melanomas and 9 melanoma cell lines by single-stranded conformational polymorphism (SSCP). The single-stranded technique showed heterozygous defects in the TP53 gene in 8 of 39 (20.5%) melanoma tumors: three new single point mutations in intronic sequences (introns 1 and 2) and exon 10, and three new single nucleotide polymorphisms located in introns 1 and 2 (C to T transition at position 11701 in intron 1; C insertion at position 11818 in intron 2; and C insertion at position 11875 in intron 2). One melanoma tumor exhibited two heterozygous alterations in the CDKN2A exon 1 one of which was novel (stop codon, and missense mutation). No defects were found in the remaining genes. These results suggest that these genes are involved in melanoma tumorigenesis, although they may be not the major targets. Other suppressor genes that may be informative of the mechanism of tumorigenesis in skin melanomas should be studied

Anaplastic Thyroid Carcinoma: A ceRNA Analysis Pointed to a Crosstalk between SOX2, TP53, and microRNA Biogenesis

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Walter Arancio

2015-01-01

Full Text Available It has been suggested that cancer stem cells (CSC may play a central role in oncogenesis, especially in undifferentiated tumours. Anaplastic thyroid carcinoma (ATC has characteristics suggestive of a tumour enriched in CSC. Previous studies suggested that the stem cell factor SOX2 has a preeminent hierarchical role in determining the characteristics of stem cells in SW1736 ATC cell line. In detail, silencing SOX2 in SW1736 is able to suppress the expression of the stem markers analysed, strongly sensitizing the line to treatment with chemotherapeutic agents. Therefore, in order to further investigate the role of SOX2 in ATC, a competing endogenous RNA (ceRNA analysis was conducted in order to isolate new functional partners of SOX2. Among the interactors, of particular interest are genes involved in the biogenesis of miRNAs (DICER1, RNASEN, and EIF2C2, in the control cell cycle (TP53, CCND1, and in mitochondrial activity (COX8A. The data suggest that stemness, microRNA biogenesis and functions, p53 regulatory network, cyclin D1, and cell cycle control, together with mitochondrial activity, might be coregulated.

Changes in protein expression in p53 deleted spontaneous thymic lymphomas

DEFF Research Database (Denmark)

Honoré, Bent; Vorum, Henrik; Pedersen, Anders Elm

2004-01-01

with the protein expression in p53+/+ and p53-/- thymocytes. Only a minority (13 proteins) of the quantitatively changed proteins were common for the two thymic lymphoma cell lines, suggesting that the p53 deficiency mainly results in genetic dysfunctions which are individual for a given tumor. Two of the detected...... structure containing motifs of the glyoxalase-bleomycin resistance protein family (MDR) as deduced from the cDNA....

Friend or Foe: MicroRNAs in the p53 network.

Science.gov (United States)

Luo, Zhenghua; Cui, Ri; Tili, Esmerina; Croce, Carlo

2018-04-10

The critical tumor suppressor gene TP53 is either lost or mutated in more than half of human cancers. As an important transcriptional regulator, p53 modulates the expression of many microRNAs. While wild-type p53 uses microRNAs to suppress cancer development, microRNAs that are activated by gain-of-function mutant p53 confer oncogenic properties. On the other hand, the expression of p53 is tightly controlled by a fine-tune machinery including microRNAs. MicroRNAs can target the TP53 gene directly or other factors in the p53 network so that expression and function of either the wild-type or the mutant forms of p53 is downregulated. Therefore, depending on the wild-type or mutant p53 context, microRNAs contribute substantially to suppress or exacerbate tumor development. Copyright © 2018. Published by Elsevier B.V.

Recombinant Protein Truncation Strategy for Inducing Bactericidal Antibodies to the Macrophage Infectivity Potentiator Protein of Neisseria meningitidis and Circumventing Potential Cross-Reactivity with Human FK506-Binding Proteins

Science.gov (United States)

Bielecka, Magdalena K.; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E.

2014-01-01

A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (−LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. PMID:25452551

Recombinant protein truncation strategy for inducing bactericidal antibodies to the macrophage infectivity potentiator protein of Neisseria meningitidis and circumventing potential cross-reactivity with human FK506-binding proteins.

Science.gov (United States)

Bielecka, Magdalena K; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E; Christodoulides, Myron

2015-02-01

A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (-LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evaluation of Tp-E Interval and Tp-E/QT Ratio in Patients with Aortic Stenosis.

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Yayla, Çağrı; Bilgin, Murat; Akboğa, Mehmet Kadri; Gayretli Yayla, Kadriye; Canpolat, Uğur; Dinç Asarcikli, Lale; Doğan, Mehmet; Turak, Osman; Çay, Serkan; Özeke, Özcan; Akyel, Ahmet; Yeter, Ekrem; Aydoğdu, Sinan

2016-05-01

The risk of syncope and sudden cardiac death due to ventricular arrhythmias increased in patients with aortic stenosis (AS). Recently, it was shown that Tp-e interval, Tp-e/QT, and Tp-e/QTc ratio can be novel indicators for prediction of ventricular arrhythmias and mortality. We aimed to investigate the association between AS and ventricular repolarization using Tp-e interval and Tp-e/QT ratio. Totally, 105 patients with AS and 60 control subjects were enrolled to this study. The severity of AS was defined by transthoracic echocardiographic examination. Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were measured from the 12-lead electrocardiogram. Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were significantly increased in parallel to the severity of AS (P ratio had significant positive correlation with mean aortic gradient (r = 0.192, P = 0.049). In multivariate logistic regression analysis, Tp-e/QTc ratio and left ventricular mass were found to be independent predictors of severe AS (P = 0.03 and P = 0.04, respectively). Our study showed that Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were increased in patients with severe AS. Tp-e/QTc ratio and left ventricular mass were found as independent predictors of severe AS. © 2015 Wiley Periodicals, Inc.

p53 regulates cytoskeleton remodeling to suppress tumor progression.

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Araki, Keigo; Ebata, Takahiro; Guo, Alvin Kunyao; Tobiume, Kei; Wolf, Steven John; Kawauchi, Keiko

2015-11-01

Cancer cells possess unique characteristics such as invasiveness, the ability to undergo epithelial-mesenchymal transition, and an inherent stemness. Cell morphology is altered during these processes and this is highly dependent on actin cytoskeleton remodeling. Regulation of the actin cytoskeleton is, therefore, important for determination of cell fate. Mutations within the TP53 (tumor suppressor p53) gene leading to loss or gain of function (GOF) of the protein are often observed in aggressive cancer cells. Here, we highlight the roles of p53 and its GOF mutants in cancer cell invasion from the perspective of the actin cytoskeleton; in particular its reorganization and regulation by cell adhesion molecules such as integrins and cadherins. We emphasize the multiple functions of p53 in the regulation of actin cytoskeleton remodeling in response to the extracellular microenvironment, and oncogene activation. Such an approach provides a new perspective in the consideration of novel targets for anti-cancer therapy.

Copy number neutral loss of heterozygosity at 17p and homozygous mutations of TP53 are associated with complex chromosomal aberrations in patients newly diagnosed with myelodysplastic syndromes.

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Svobodova, Karla; Zemanova, Zuzana; Lhotska, Halka; Novakova, Milena; Podskalska, Lucie; Belickova, Monika; Brezinova, Jana; Sarova, Iveta; Izakova, Silvia; Lizcova, Libuse; Berkova, Adela; Siskova, Magda; Jonasova, Anna; Cermak, Jaroslav; Michalova, Kyra

2016-03-01

Complex karyotypes are seen in approximately 20% of patients with myelodysplastic syndromes (MDS) and are associated with a high risk of transformation to acute myeloid leukemia and poor outcomes in patients. Copy number neutral loss of heterozygosity (CN-LOH, i.e., both copies of a chromosomal pair or their parts originate from one parent) might contribute to increased genomic instability in the bone-marrow cells of patients with MDS. The pathological potential of CN-LOH, which arises as a clonal aberration in a proportion of somatic cells, consists of tumor suppressor gene and oncogene homozygous mutations. The aim of our study was to evaluate the frequency of CN-LOH at 17p in bone-marrow cells of newly diagnosed MDS patients with complex chromosomal aberrations and to assess its correlation with mutations in the TP53 gene (17p13.1). CN-LOH was detected in 40 chromosomal regions in 21 (29%) of 72 patients analyzed. The changes in 27 of the 40 regions identified were sporadic. The most common finding was CN-LOH of the short arm of chromosome 17, which was detected in 13 (18%) of 72 patients. A mutational analysis confirmed the homozygous mutation of TP53 in all CN-LOH 17p patients, among which two frameshift mutations are not registered in the International Agency for Research on Cancer TP53 Database. CN-LOH 17p correlated with aggressive disease (median overall survival 4 months) and was strongly associated with a complex karyotype in the cohort studied, which might cause rapid disease progression in high-risk MDS. No other CN-LOH region previously recorded in MDS or AML patients (1p, 4q, 7q, 11q, 13q, 19q, 21q) was detected in our cohort of patients with complex karyotype examined at the diagnosis of MDS. The LOH region appeared to be balanced (i.e., with no DNA copy number change) when examined with conventional and molecular cytogenetic methods. Therefore, a microarray that detects single-nucleotide polymorphisms is an ideal method with which to identify and

p53 Protein interacts specifically with the meiosis-specific mammalian RecA-like protein DMC1 in meiosis.

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Habu, Toshiyuki; Wakabayashi, Nobunao; Yoshida, Kayo; Yomogida, Kenntaro; Nishimune, Yoshitake; Morita, Takashi

2004-06-01

The tumor suppressor protein p53 is specifically expressed during meiosis in spermatocytes. Subsets of p53 knockout mice exhibit testicular giant cell degenerative syndrome, which suggests p53 may be associated with meiotic cell cycle and/or DNA metabolism. Here, we show that p53 binds to the mouse meiosis-specific RecA-like protein Mus musculus DMC1 (MmDMC1). The C-terminal domain (amino acid 234-340) of MmDMC1 binds to DNA-binding domain of p53 protein. p53 might be involved in homologous recombination and/or checkpoint function by directly binding to DMC1 protein to repress genomic instability in meiotic germ cells.

Tp-e interval and Tp-e/QT ratio in patients with celiac disease.

Science.gov (United States)

Demirtaş, K; Yayla, Ç; Yüksel, M; Açar, B; Ünal, S; Ertem, A G; Kaplan, M; Akpinar, M Y; Kiliç, Z M Y; Kayaçetin, E

2017-11-01

Celiac disease is a chronic immune-mediated disease of the small intestine. It has been known that dilated cardiomyopathy and ischemic coronary artery disease have become more frequent in patients with celiac disease. The aim of the study was to assess Tp-e interval and Tp-e/QT ratio in patients with celiac disease. This study was conducted at a single center in collaboration with gastroenterology and cardiology clinics. Between January 2014 and June 2015, a total of 76 consecutive patients were enrolled (38 patients with celiac disease and 38 control subjects). Tp-e interval, Tp-e/QT and Tp-e/QTc ratio were measured from the 12-lead electrocardiogram. Tp-e interval (64.2±11.0 vs. 44.5±6.0; pceliac disease than control subjects. There was a significant positive correlation between Tp-e/QTc ratio and disease duration in patients with celiac disease (r=0.480, p=0.003) and also there was a significant positive correlation between Tp-e/QTc ratio and erythrocyte sedimentation rate (r=0.434, pceliac disease. Whether these changes increase the risk of ventricular arrhythmia deserve further studies. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

[Evaluation of the Performance of Two Kinds of Anti-TP Enzyme-Linked Immunosorbent Assay].

Science.gov (United States)

Gao, Nan; Huang, Li-Qin; Wang, Rui; Jia, Jun-Jie; Wu, Shuo; Zhang, Jing; Ge, Hong-Wei

2018-06-01

To evaluate the accuracy and precision of 2 kinds of anti-treponema pallidum (anti-TP) ELISA reagents in our laboratory for detecting the anti-TP in voluntary blood donors, so as to provide the data support for use of ELISA reagents after introduction of chemiluminescene immunoassay (CLIA). The route detection of anti-TP was performed by using 2 kinds of ELISA reagents, then 546 responsive positive samples detected by anti-TP ELISA were collected, and the infections status of samples confirmed by treponema pallidum particle agglutination (TPPA) test was identified. The confirmed results of responsive samples detected by 2 kinds of anti-TP ELISA reagents were compared, the accuracy of 2 kinds of anti-TP ELISA reagents was analyzed by drawing ROC and comparing area under curve (AUC), and precision of 2 kinds of anti-TP ELISA reagents was compared by statistical analysis of quality control data from 7.1 2016 to 6.30 2017. There were no statistical difference in confirmed positive rate of responsive samples and weak positive samples between 2 kinds of anti-TP ELISA reagents. The responsive samples detected by 2 kinds of anti-TP ELISA reagents accounted for 85.53%(467/546) of all responsive samples, the positive rate confirmed by TPPA test was 82.87%. 44 responsive samples detected by anti-TP ELISA reagent A and 35 responsive samples detected by anti-TP ELISA reagent B were confirmed to be negative by TPPA test. Comparison of AUC showed that the accuracy of 2 kinds of anti-TP ELISA reagents was more high, the difference between 2 reagents was not statistically significant. The coefficient of variation (CV) of anti-TP ELISA reagent A and B was 14.98% and 18.04% respectively, which met the precision requirement of ELISA test. The accuracy and precision of 2 kinds of anti-TP ELISA reagents used in our laboratory are similar, and using any one of anti-TP ELISA reagents all can satisfy the requirements of blood screening.

Mutational analysis of the activator of late transcription, Alt , in the lactococcal bacteriophage TP901-1

DEFF Research Database (Denmark)

Pedersen, Margit; Hammer, Karin

2007-01-01

An activator protein, Alt, synthesized during the early state of lytic infection is required for transcription of the late operon in the lactococcal phage TP901-1. In order to identify amino acid residues in the Alt protein required for activation of the TP901-1 late promoter, Plate, hydroxylamine...

Purification, crystallization and preliminary X-ray analysis of TP0435 (Tp17) from the syphilis spirochete Treponema pallidum

International Nuclear Information System (INIS)

Brautigam, Chad A.; Deka, Ranjit K.; Norgard, Michael V.

2013-01-01

The soluble portion of TP0435, a putative periplasmic lipoprotein from the syphilis spirochete T. pallidum, has been purified and crystallized in a rhombohedral space group. A complete native data set has been collected to 2.4 Å resolution. Syphilis, caused by the bacterial spirochete Treponema pallidum, remains a prominent sexually transmitted infection worldwide. Despite sequencing of the genome of this obligate human pathogen 15 years ago, the functions of a large number of the gene products of T. pallidum are still unknown, particularly with respect to those of the organism’s periplasmic lipoproteins. To better understand their functions, a structural biology approach has been pursued. To this end, the soluble portion of the T. pallidum TP0435 lipoprotein (also known as Tp17) was cloned, hyper-expressed in Escherichia coli and purified to apparent homogeneity. The protein crystals obtained from this preparation diffracted to 2.4 Å resolution and had the symmetry of space group R3. In the hexagonal setting, the unit-cell parameters were a = b = 85.7, c = 85.4 Å

Expression of a truncated receptor protein tyrosine phosphatase kappa in the brain of an adult transgenic mouse

DEFF Research Database (Denmark)

Shen, P; Canoll, P D; Sap, J

1999-01-01

processes such as axonal growth and target recognition, as has been demonstrated for certain Drosophila RPTPs. The brain distribution of RPTP-kappa-expressing cells has not been determined, however. In a gene-trap mouse model with a beta-gal+neo (beta-geo) insertion in the endogenous RPTP-kappa gene......-6596]. Nevertheless, since the transgene's expression is driven by the endogenous RPTP-kappa promoter, distribution of the truncated RPTP-kappa/beta-geo fusion protein should reflect the regional and cellular expression of wild-type RPTP-kappa, and thus may identify sites where RPTP-kappa is important. Towards...... that goal, we have used this mouse model to map the distribution of the truncated RPTP-kappa/beta-geo fusion protein in the adult mouse brain using beta-galactosidase as a marker enzyme. Visualization of the beta-galactosidase activity revealed a non-random pattern of expression, and identified cells...

HPV has left the building – the absence of detectable HPV DNA and the presence of r allele/s for the P72R polymorphism in the TP53 gene may call for more aggressive therapeutic approach in HPV-associated tumours

International Nuclear Information System (INIS)

Petkova, Rumena; Chelenkova, Pavlina; Yemendzhiev, Husein; Tsekov, Iliya; Kalvatchev, Zlatko; Chakarov, Stoyan

2013-01-01

HPV infection is a major pathogenetic factor in cervical carcinoma as well as in many of the squamous cancers of head and neck and other epithelial cancers. Persistence of HPV DNA detectable by routine methods is considered to be a risk factor for advanced CIN and, in patients treated by surgery or non-surgical treatment modalities (radiotherapy, chemotherapy), HPV persistence is believed to be associated with increased risk for local recurrence. In terms of survival, however, it has been repeatedly proven that patients with cervical cancer and other HPV-associated cancers with detectable HPV DNA tend to have better outcomes than patients with HPV-negative tumours. The P72R polymorphism in the human TP53 gene has been contemplated as an independent phenotype modifier in cancers, especially the R allele which has been shown to confer higher pro-apoptotic properties to the resultant p53 protein. It has been demonstrated, however, that RR homozygotes were much more common in study groups with HPV-associated tumours than the other two genotypes and that the P allele in P/R heterozygotes was preferentially lost while the R allele was preferentially retained and mutated. It is possible that HPV-dependent carcinogenesis strictly relies on the presence of HPV and the expression of the E6 and E7 onco proteins only in the initial phases of transformation of infected cells (e.g. CIN). It may be associated with activation of latent HPV that would create a background of decreased control over the integrity of the genome of the host cell. The process can develop further by mechanisms independent of the presence of HPV and if the virus clears at some later point, that would not halt the already ongoing neoplastic transformation. Absence of HPV DNA in cervical tumours, whether before or after treatment, is not a reason to decrease vigilant monitoring and rule out the need for further treatment, as it may be quite possible that the TP53 gene of the infected cells has already been

Interaction of p53 with prolyl isomerases: Healthy and unhealthy relationships.

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Mantovani, Fiamma; Zannini, Alessandro; Rustighi, Alessandra; Del Sal, Giannino

2015-10-01

The p53 protein family, comprising p53, p63 and p73, is primarily involved in preserving genome integrity and preventing tumor onset, and also affects a range of physiological processes. Signal-dependent modifications of its members and of other pathway components provide cells with a sophisticated code to transduce a variety of stress signaling into appropriate responses. TP53 mutations are highly frequent in cancer and lead to the expression of mutant p53 proteins that are endowed with oncogenic activities and sensitive to stress signaling. p53 family proteins have unique structural and functional plasticity, and here we discuss the relevance of prolyl-isomerization to actively shape these features. The anti-proliferative functions of the p53 family are carefully activated upon severe stress and this involves the interaction with prolyl-isomerases. In particular, stress-induced stabilization of p53, activation of its transcriptional control over arrest- and cell death-related target genes and of its mitochondrial apoptotic function, as well as certain p63 and p73 functions, all require phosphorylation of specific S/T-P motifs and their subsequent isomerization by the prolyl-isomerase Pin1. While these functions of p53 counteract tumorigenesis, under some circumstances their activation by prolyl-isomerases may have negative repercussions (e.g. tissue damage induced by anticancer therapies and ischemia-reperfusion, neurodegeneration). Moreover, elevated Pin1 levels in tumor cells may transduce deregulated phosphorylation signaling into activation of mutant p53 oncogenic functions. The complex repertoire of biological outcomes induced by p53 finds mechanistic explanations, at least in part, in the association between prolyl-isomerases and the p53 pathway. This article is part of a Special Issue entitled Proline-directed foldases: Cell signaling catalysts and drug targets. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluation of Tp-Te Interval and Tp-Te/QT Ratio in Patients with Coronary Slow Flow Tp-Te/QT Ratio and Coronary Slow Flow.

Science.gov (United States)

Tenekecioglu, Erhan; Karaagac, Kemal; Yontar, Osman Can; Agca, Fahriye Vatansever; Ozluk, Ozlem Arican; Tutuncu, Ahmet; Arslan, Burhan; Yilmaz, Mustafa

2015-06-01

Coronary slow flow (CSF) phenomenon is described by angiographically normal coronary arteries with delayed opacification of the distal vasculature. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-Te) may correspond to the transmural dispersion of the repolarization and that increased Tp-Te interval and Tp-Te/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate the ventricular repolarization by using Tp-Te interval and Tp-Te/QT ratio in patients with CSF. This study included 50 CSF patients (40 male, mean age 48.6±12.5 years) and 40 control individuals (23 male, mean age 47.8±12.5 years). Tp-Te interval and Tp-Te/QT ratio were measured from the 12-lead electrocardiogram. These parameters were compared in groups. Baseline characteristics of the study groups were comparable. In electrocardiographic parameters analysis, QT and corrected QT were similar in CSF patients compared to the controls (357±35.2 vs 362±38.0 milliseconds and 419±25.8 vs 430±44.2 milliseconds, all p value >0.05). Tp-Te interval, Tp-Te/QT and Tp-Te/QTc ratio were significantly higher in CSF patients (85±13.7 vs 74±9.9 milliseconds and 0.24±0.03 vs 0.20±0.02 and 0.20±0.03 vs 0.17±0.02 all p value ratio are prolonged in patients with CSF.

MG132 plus apoptosis antigen-1 (APO-1) antibody cooperate to restore p53 activity inducing autophagy and p53-dependent apoptosis in HPV16 E6-expressing keratinocytes.

Science.gov (United States)

Lagunas-Martínez, Alfredo; García-Villa, Enrique; Arellano-Gaytán, Magaly; Contreras-Ochoa, Carla O; Dimas-González, Jisela; López-Arellano, María E; Madrid-Marina, Vicente; Gariglio, Patricio

2017-01-01

The E6 oncoprotein can interfere with the ability of infected cells to undergo programmed cell death through the proteolytic degradation of proapoptotic proteins such as p53, employing the proteasome pathway. Therefore, inactivation of the proteasome through MG132 should restore the activity of several proapoptotic proteins. We investigated whether in HPV16 E6-expressing keratinocytes (KE6 cells), the restoration of p53 levels mediated by MG132 and/or activation of the CD95 pathway through apoptosis antigen-1 (APO-1) antibody are responsible for the induction of apoptosis. We found that KE6 cells underwent apoptosis mainly after incubation for 24 h with MG132 alone or APO-1 plus MG132. Both treatments activated the extrinsic and intrinsic apoptosis pathways. Autophagy was also activated, principally by APO-1 plus MG132. Inhibition of E6-mediated p53 proteasomal degradation by MG132 resulted in the elevation of p53 protein levels and its phosphorylation in Ser46 and Ser20; the p53 protein was localized mainly at nucleus after treatment with MG132 or APO-1 plus MG132. In addition, induction of its transcriptional target genes such as p21, Bax and TP53INP was observed 3 and 6 h after treatment. Also, LC3 mRNA was induced after 3 and 6 h, which correlates with lipidation of LC3B protein and induction of autophagy. Finally, using pifithrin alpha we observed a decrease in apoptosis induced by MG132, and by APO-1 plus MG132, suggesting that restoration of APO-1 sensitivity occurs in part through an increase in both the levels and the activity of p53. The use of small molecules to inhibit the proteasome pathway might permit the activation of cell death, providing new opportunities for CC treatment.

Structure and stability insights into tumour suppressor p53 evolutionary related proteins.

Directory of Open Access Journals (Sweden)

Bruno Pagano

Full Text Available The p53 family of genes and their protein products, namely, p53, p63 and p73, have over one billion years of evolutionary history. Advances in computational biology and genomics are enabling studies of the complexities of the molecular evolution of p53 protein family to decipher the underpinnings of key biological conditions spanning from cancer through to various metabolic and developmental disorders and facilitate the design of personalised medicines. However, a complete understanding of the inherent nature of the thermodynamic and structural stability of the p53 protein family is still lacking. This is due, to a degree, to the lack of comprehensive structural information for a large number of homologous proteins and to an incomplete knowledge of the intrinsic factors responsible for their stability and how these might influence function. Here we investigate the thermal stability, secondary structure and folding properties of the DNA-binding domains (DBDs of a range of proteins from the p53 family using biophysical methods. While the N- and the C-terminal domains of the p53 family show sequence diversity and are normally targets for post-translational modifications and alternative splicing, the central DBD is highly conserved. Together with data obtained from Molecular Dynamics simulations in solution and with structure based homology modelling, our results provide further insights into the molecular properties of evolutionary related p53 proteins. We identify some marked structural differences within the p53 family, which could account for the divergence in biological functions as well as the subtleties manifested in the oligomerization properties of this family.

Radiosensitization dependent on p53 function in bronchial carcinoma cells by the isoflavone genistein and estradiol in vitro

International Nuclear Information System (INIS)

Hermann, R.M.; Fest, J.; Christiansen, H.; Hille, A.; Rave-Fraenk, M.; Nitsche, M.; Gruendker, C.; Viereck, V.; Jarry, H.; Schmidberger, H.

2007-01-01

Background and Purpose: Simultaneous radiotherapy with chemotherapy is a standard treatment for inoperable non-small cell lung cancer (NSCLC), but the clinical outcome still remains poor. To further intensify treatment, substances need to be identified, which increase the effect of radiation on tumor cells without further enhancing toxicity to normal tissue. Hormones have a different toxicity profile than radiation or cytostatic drugs. As NSCLC often express estrogen receptors (ERs), the combination of genistein or estradiol and radiation in vitro was investigated. Material and Methods: A549 NSCLC cells with an inducible expression of a mutated TP53 and fibroblasts of a male donor (DF-18) were examined. ER expression was immunocytologically confirmed in all studied cell lines. Clonogenic survival was measured after incubation of the cells with genistein or estradiol (0.01 μM and 10 μM as maximum clinically applicable dose) and irradiation with different doses (0-4 Gy). The differentiation state of fibroblasts after combined therapy was analyzed. Results: A549 cells expressing mutated TP53 were more radioresistant than TP53 wild-type cells. Incubation of nonfunctional TP53 cells with genistein or estradiol increased radiosensitivity in both tested concentrations. By contrast, radiosensitivity of A549 with wild-type TP53 and DF-18 was not altered by hormonal incubation. In DF-18 radiation induced growth arrest that was not increased by additional hormonal incubation. Conclusion: NSCLC cells with nonfunctional TP53 might be sensitized against radiation by genistein or estradiol. As genistein is better tolerable than estradiol in patients, additional studies are warranted to assess potential gains of this combination therapy

Malignant Trigeminal Nerve Sheath Tumor and Anaplastic Astrocytoma Collision Tumor with High Proliferative Activity and Tumor Suppressor P53 Expression

Directory of Open Access Journals (Sweden)

Maher Kurdi

2014-01-01

Full Text Available Background. The synchronous development of two primary brain tumors of distinct cell of origin in close proximity or in contact with each other is extremely rare. We present the first case of collision tumor with two histological distinct tumors. Case Presentation. A 54-year-old woman presented with progressive atypical left facial pain and numbness for 8 months. MRI of the brain showed left middle cranial fossa heterogeneous mass extending into the infratemporal fossa. At surgery, a distinct but intermingled intra- and extradural tumor was demonstrated which was completely removed through left orbitozygomatic-temporal craniotomy. Histopathological examination showed that the tumor had two distinct components: malignant nerve sheath tumor of the trigeminal nerve and temporal lobe anaplastic astrocytoma. Proliferative activity and expressed tumor protein 53 (TP53 gene mutations were demonstrated in both tumors. Conclusions. We describe the first case of malignant trigeminal nerve sheath tumor (MTNST and anaplastic astrocytoma in collision and discuss the possible hypothesis of this rare occurrence. We propose that MTNST, with TP53 mutation, have participated in the formation of anaplastic astrocytoma, or vice versa.

Co-operative intra-protein structural response due to protein-protein complexation revealed through thermodynamic quantification: study of MDM2-p53 binding.

Science.gov (United States)

Samanta, Sudipta; Mukherjee, Sanchita

2017-10-01

The p53 protein activation protects the organism from propagation of cells with damaged DNA having oncogenic mutations. In normal cells, activity of p53 is controlled by interaction with MDM2. The well understood p53-MDM2 interaction facilitates design of ligands that could potentially disrupt or prevent the complexation owing to its emergence as an important objective for cancer therapy. However, thermodynamic quantification of the p53-peptide induced structural changes of the MDM2-protein remains an area to be explored. This study attempts to understand the conformational free energy and entropy costs due to this complex formation from the histograms of dihedral angles generated from molecular dynamics simulations. Residue-specific quantification illustrates that, hydrophobic residues of the protein contribute maximum to the conformational thermodynamic changes. Thermodynamic quantification of structural changes of the protein unfold the fact that, p53 binding provides a source of inter-element cooperativity among the protein secondary structural elements, where the highest affected structural elements (α2 and α4) found at the binding site of the protein affects faraway structural elements (β1 and Loop1) of the protein. The communication perhaps involves water mediated hydrogen bonded network formation. Further, we infer that in inhibitory F19A mutation of P53, though Phe19 is important in the recognition process, it has less prominent contribution in the stability of the complex. Collectively, this study provides vivid microscopic understanding of the interaction within the protein complex along with exploring mutation sites, which will contribute further to engineer the protein function and binding affinity.

Co-operative intra-protein structural response due to protein-protein complexation revealed through thermodynamic quantification: study of MDM2-p53 binding

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Samanta, Sudipta; Mukherjee, Sanchita

2017-10-01

The p53 protein activation protects the organism from propagation of cells with damaged DNA having oncogenic mutations. In normal cells, activity of p53 is controlled by interaction with MDM2. The well understood p53-MDM2 interaction facilitates design of ligands that could potentially disrupt or prevent the complexation owing to its emergence as an important objective for cancer therapy. However, thermodynamic quantification of the p53-peptide induced structural changes of the MDM2-protein remains an area to be explored. This study attempts to understand the conformational free energy and entropy costs due to this complex formation from the histograms of dihedral angles generated from molecular dynamics simulations. Residue-specific quantification illustrates that, hydrophobic residues of the protein contribute maximum to the conformational thermodynamic changes. Thermodynamic quantification of structural changes of the protein unfold the fact that, p53 binding provides a source of inter-element cooperativity among the protein secondary structural elements, where the highest affected structural elements (α2 and α4) found at the binding site of the protein affects faraway structural elements (β1 and Loop1) of the protein. The communication perhaps involves water mediated hydrogen bonded network formation. Further, we infer that in inhibitory F19A mutation of P53, though Phe19 is important in the recognition process, it has less prominent contribution in the stability of the complex. Collectively, this study provides vivid microscopic understanding of the interaction within the protein complex along with exploring mutation sites, which will contribute further to engineer the protein function and binding affinity.

Studying p53 family proteins in yeast: Induction of autophagic cell death and modulation by interactors and small molecules

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Leão, Mariana; Gomes, Sara; Bessa, Cláudia; Soares, Joana; Raimundo, Liliana [REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n. 164, 4050-313 Porto (Portugal); Monti, Paola; Fronza, Gilberto [Mutagenesis Unit, Istituto di Ricerca e Cura a Carattere Scientifico Azienda Ospedaliera Universitaria San Martino-IST-Istituto Nazionale per la Ricerca sul Cancro, 16132 Genoa (Italy); Pereira, Clara [REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n. 164, 4050-313 Porto (Portugal); Saraiva, Lucília, E-mail: lucilia.saraiva@ff.up.pt [REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n. 164, 4050-313 Porto (Portugal)

2015-01-01

In this work, the yeast Saccharomyces cerevisiae was used to individually study human p53, p63 (full length and truncated forms) and p73. Using this cell system, the effect of these proteins on cell proliferation and death, and the influence of MDM2 and MDMX on their activities were analyzed. When expressed in yeast, wild-type p53, TAp63, ΔNp63 and TAp73 induced growth inhibition associated with S-phase cell cycle arrest. This growth inhibition was accompanied by reactive oxygen species production and autophagic cell death. Furthermore, they stimulated rapamycin-induced autophagy. On the contrary, none of the tested p53 family members induced apoptosis either per se or after apoptotic stimuli. As previously reported for p53, also TAp63, ΔNp63 and TAp73 increased actin expression levels and its depolarization, suggesting that ACT1 is also a p63 and p73 putative yeast target gene. Additionally, MDM2 and MDMX inhibited the activity of all tested p53 family members in yeast, although the effect was weaker on TAp63. Moreover, Nutlin-3a and SJ-172550 were identified as potential inhibitors of the p73 interaction with MDM2 and MDMX, respectively. Altogether, the yeast-based assays herein developed can be envisaged as a simplified cell system to study the involvement of p53 family members in autophagy, the modulation of their activities by specific interactors (MDM2 and MDMX), and the potential of new small molecules to modulate these interactions. - Highlights: • p53, p63 and p73 are individually studied in the yeast S. cerevisiae. • p53 family members induce ROS production, cell cycle arrest and autophagy in yeast. • p53 family members increase actin depolarization and expression levels in yeast. • MDM2 and MDMX inhibit the activity of p53 family members in yeast. • Yeast can be a useful tool to study the biology and drugability of p53, p63 and p73.

Studying p53 family proteins in yeast: Induction of autophagic cell death and modulation by interactors and small molecules

International Nuclear Information System (INIS)

Leão, Mariana; Gomes, Sara; Bessa, Cláudia; Soares, Joana; Raimundo, Liliana; Monti, Paola; Fronza, Gilberto; Pereira, Clara; Saraiva, Lucília

2015-01-01

In this work, the yeast Saccharomyces cerevisiae was used to individually study human p53, p63 (full length and truncated forms) and p73. Using this cell system, the effect of these proteins on cell proliferation and death, and the influence of MDM2 and MDMX on their activities were analyzed. When expressed in yeast, wild-type p53, TAp63, ΔNp63 and TAp73 induced growth inhibition associated with S-phase cell cycle arrest. This growth inhibition was accompanied by reactive oxygen species production and autophagic cell death. Furthermore, they stimulated rapamycin-induced autophagy. On the contrary, none of the tested p53 family members induced apoptosis either per se or after apoptotic stimuli. As previously reported for p53, also TAp63, ΔNp63 and TAp73 increased actin expression levels and its depolarization, suggesting that ACT1 is also a p63 and p73 putative yeast target gene. Additionally, MDM2 and MDMX inhibited the activity of all tested p53 family members in yeast, although the effect was weaker on TAp63. Moreover, Nutlin-3a and SJ-172550 were identified as potential inhibitors of the p73 interaction with MDM2 and MDMX, respectively. Altogether, the yeast-based assays herein developed can be envisaged as a simplified cell system to study the involvement of p53 family members in autophagy, the modulation of their activities by specific interactors (MDM2 and MDMX), and the potential of new small molecules to modulate these interactions. - Highlights: • p53, p63 and p73 are individually studied in the yeast S. cerevisiae. • p53 family members induce ROS production, cell cycle arrest and autophagy in yeast. • p53 family members increase actin depolarization and expression levels in yeast. • MDM2 and MDMX inhibit the activity of p53 family members in yeast. • Yeast can be a useful tool to study the biology and drugability of p53, p63 and p73

p18(Hamlet) mediates different p53-dependent responses to DNA-damage inducing agents.

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Lafarga, Vanesa; Cuadrado, Ana; Nebreda, Angel R

2007-10-01

Cells organize appropriate responses to environmental cues by activating specific signaling networks. Two proteins that play key roles in coordinating stress responses are the kinase p38alpha (MAPK14) and the transcription factor p53 (TP53). Depending on the nature and the extent of the stress-induced damage, cells may respond by arresting the cell cycle or by undergoing cell death, and these responses are usually associated with the phosphorylation of particular substrates by p38alpha as well as the activation of specific target genes by p53. We recently characterized a new p38alpha substrate, named p18(Hamlet) (ZNHIT1), which mediates p53-dependent responses to different genotoxic stresses. Thus, cisplatin or UV light induce stabilization of the p18(Hamlet) protein, which then enhances the ability of p53 to bind to and activate the promoters of pro-apoptotic genes such as NOXA and PUMA leading to apoptosis induction. In a similar way, we report here that p18(Hamlet) can also mediate the cell cycle arrest induced in response to gamma-irradiation, by participating in the p53-dependent upregulation of the cell cycle inhibitor p21(Cip1) (CDKN1A).

A Novel Interaction of Ecdysoneless (ECD) Protein with R2TP Complex Component RUVBL1 Is Required for the Functional Role of ECD in Cell Cycle Progression.

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Mir, Riyaz A; Bele, Aditya; Mirza, Sameer; Srivastava, Shashank; Olou, Appolinaire A; Ammons, Shalis A; Kim, Jun Hyun; Gurumurthy, Channabasavaiah B; Qiu, Fang; Band, Hamid; Band, Vimla

2015-12-28

Ecdysoneless (ECD) is an evolutionarily conserved protein whose germ line deletion is embryonic lethal. Deletion of Ecd in cells causes cell cycle arrest, which is rescued by exogenous ECD, demonstrating a requirement of ECD for normal mammalian cell cycle progression. However, the exact mechanism by which ECD regulates cell cycle is unknown. Here, we demonstrate that ECD protein levels and subcellular localization are invariant during cell cycle progression, suggesting a potential role of posttranslational modifications or protein-protein interactions. Since phosphorylated ECD was recently shown to interact with the PIH1D1 adaptor component of the R2TP cochaperone complex, we examined the requirement of ECD phosphorylation in cell cycle progression. Notably, phosphorylation-deficient ECD mutants that failed to bind to PIH1D1 in vitro fully retained the ability to interact with the R2TP complex and yet exhibited a reduced ability to rescue Ecd-deficient cells from cell cycle arrest. Biochemical analyses demonstrated an additional phosphorylation-independent interaction of ECD with the RUVBL1 component of the R2TP complex, and this interaction is essential for ECD's cell cycle progression function. These studies demonstrate that interaction of ECD with RUVBL1, and its CK2-mediated phosphorylation, independent of its interaction with PIH1D1, are important for its cell cycle regulatory function. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Cutaneous hidradenocarcinoma: a clinicopathological, immunohistochemical, and molecular biologic study of 14 cases, including Her2/neu gene expression/amplification, TP53 gene mutation analysis, and t(11;19) translocation.

Science.gov (United States)

Kazakov, Dmitry V; Ivan, Doina; Kutzner, Heinz; Spagnolo, Dominic V; Grossmann, Petr; Vanecek, Tomas; Sima, Radek; Kacerovska, Denisa; Shelekhova, Ksenia V; Denisjuk, Natalja; Hillen, Uwe; Kuroda, Naoto; Mukensnabl, Petr; Danis, Dusan; Michal, Michal

2009-05-01

, in 2 cases, a minority of the neoplastic cells (10%-20%) demonstrated nuclear staining, whereas the remaining 4 cases were negative. Of 9 specimens of hidradenocarcinoma studied for TP53 mutations, 2 harbored mutations, whereas the remaining 7 specimens showed the wild-type sequence. Of 11 specimens studied for translocation t(11;19), 2 cases harbored the translocation. It is concluded that cutaneous hidradenocarcinomas show some microscopic heterogeneity and comprise both low- and high-grade lesions that cytologically are similar to their benign counterpart, the hidradenoma. Within the spectrum of low-grade lesions, there seem to exist tumors almost indistinguishable from hidradenomas but still being capable of regional or distant metastasis. Similar to hidradenomas, hidradenocarcinomas show a t(11;19) translocation, but it is a significantly rarer event. Even rarer is the amplification of the Her2/neu gene. Of note is the relatively low frequency of TP53 mutations despite a high rate of p53 protein expression at the immunohistochemical level.

The combination of heteroduplex analysis and protein truncation test for exact detection of the APC gene mutations

International Nuclear Information System (INIS)

Tomka, M.; Kirchhoff, T.; Stefurkova, V.; Zajac, V.; Kulcsar, L.

1998-01-01

Familial adenomatous polyposis (FAP) is usually associated with mutation in the adenomatous polyposis coli (APC) gene. To examine the occurrence of these mutations in the number of FAP suspected families from the whole Slovakia effectively, we have applied heteroduplex analysis (HDA) and protein truncation test (PTT) for the analyses of 2-5 base pair deletions and point mutations of the APC gene. In the analyzed exon 15 of the APC gene determined by the primers 15Efor-15Grev for HDA and 15ET7-15J3 for PTT more than 70% of mutations should be deletions [3, 12], which are detectable by HDA. In our collection of 5 FAP families mutations in the APC gene were found in families 10, 27 and 41 using HDA. By PTT test the formation of truncated APC protein in FAP families 2, 10, 16 and 27 were revealed. The necessity of combination of at least HDA and PTT techniques for exact detection of APC mutations in analyzed APC region is discussed. (authors)

Evidence for the interaction of the regulatory protein Ki-1/57 with p53 and its interacting proteins

International Nuclear Information System (INIS)

Nery, Flavia C.; Rui, Edmilson; Kuniyoshi, Tais M.; Kobarg, Joerg

2006-01-01

Ki-1/57 is a cytoplasmic and nuclear phospho-protein of 57 kDa and interacts with the adaptor protein RACK1, the transcription factor MEF2C, and the chromatin remodeling factor CHD3, suggesting that it might be involved in the regulation of transcription. Here, we describe yeast two-hybrid studies that identified a total of 11 proteins interacting with Ki-1/57, all of which interact or are functionally associated with p53 or other members of the p53 family of proteins. We further found that Ki-1/57 is able to interact with p53 itself in the yeast two-hybrid system when the interaction was tested directly. This interaction could be confirmed by pull down assays with purified proteins in vitro and by reciprocal co-immunoprecipitation assays from the human Hodgkin analogous lymphoma cell line L540. Furthermore, we found that the phosphorylation of p53 by PKC abolishes its interaction with Ki-1/57 in vitro

Role of wild-type p53 in apoptotic and non-apoptotic cell death induced by X-irradiation and heat treatment in p53-mutated mouse M10 cells

International Nuclear Information System (INIS)

Ito, Atsushi; Nakano, Hisako; Shinohara, Kunio

2010-01-01

The sensitizing effects of wild-type p53 on X-ray-induced cell death and on heat-induced apoptosis in M10, a radiosensitive and Trp53 (mouse p53 gene)-mutated lymphoma cell line which dies through necrosis by X-irradiation, were investigated using three M10 derived transfectants with wild-type TP53 (human p53 gene). Cell death was determined by colony formation and/or dye exclusion test, and apoptosis was detected as the changes in nuclear morphology by Giemsa staining. Expression of wild-type p53 protein increased radiosensitivity of cell death as determined by both clonogenic and dye exclusion assays. This increase in radiosensitivity was attributable largely to apoptosis induction in addition to a small enhancement of necrosis. Interestingly neither pathway to cell death was accompanied by caspase-3 activation. On the other hand, heat-induced caspase-3 dependent apoptotic cell death without transfection was further increased by the transfection of wild-type p53. In conclusion, the introduction of wild-type p53 enhanced apoptotic cell death by X-rays or heat via different mechanisms that do or do not activate caspase-3, respectively. In addition, p53 also enhanced the X-ray-induced necrosis in M10 cells. (author)

Disruption of the MDM2-p53 interaction strongly potentiates p53-dependent apoptosis in cisplatin-resistant human testicular carcinoma cells via the Fas/FasL pathway

NARCIS (Netherlands)

Koster, R.; Timmer-Bosscha, H.; Bischoff, R.; Gietema, J. A.; de Jong, S.

Wild-type p53 has a major role in the response and execution of apoptosis after chemotherapy in many cancers. Although high levels of wild-type p53 and hardly any TP53 mutations are found in testicular cancer (TC), chemotherapy resistance is still observed in a significant subgroup of TC patients.

Influence of p53 (rs1625895 polymorphism in kidney transplant recipients

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Negar Azarpira

2014-01-01

Full Text Available Reperfusion injury predisposes the kidney allograft to acute rejection. Apoptosis is a mechanism that results in graft injury, and TP53 is an important involved gene. To determine the association between single nucleotide polymorphism (SNP in the pro-apoptotic protein p53 (rs1625895 and acute rejection in renal transplants, we studied 100 recipients of kidney allografts and 100 healthy individuals served as controls. The polymorphism was determined by the polymerase chain reaction restriction-fragment length polymorphism (PCR-RFLP test. Overall, 31 recipients developed rejection. There was no difference in the genotype frequencies between the recipients and the controls. However, we found a difference of genotype and allele frequencies between recipients with and those without rejection. The WW genotype was more frequent in recipients with rejection. Although rejection is a complex immunologic event and functional importance of SNPs has not been confirmed yet, we suggest that wild type p53 may promote apoptosis during inflammation.

TFP5/TP5 peptide provides neuroprotection in the MPTP model of Parkinson′s disease

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B K Binukumar

2016-01-01

Full Text Available Cyclin-dependent kinase 5 (Cdk5 is a member of the serine-threonine kinase family of cyclin-dependent kinases. Cdk5 is critical to normal mammalian nervous system development and plays important regulatory roles in multiple cellular functions. Recent evidence indicates that Cdk5 is inappropriately activated in several neurodegenerative conditions, including Parkinson′s disease (PD. PD is a chronic neurodegenerative disorder characterized by the loss of dopamine neurons in the substantia nigra, decreased striatal dopamine levels, and consequent extrapyramidal motor dysfunction. During neurotoxicity, p35 is cleaved to form p25. Binding of p25 with Cdk5 leads deregulation of Cdk5 resulting in number of neurodegenerative pathologies. To date, strategies to specifically inhibit Cdk5 hyperactivity have not been successful without affecting normal Cdk5 activity. Here we show that inhibition of p25/Cdk5 hyperactivation through TFP5/TP5, truncated 24-aa peptide derived from the Cdk5 activator p35 rescues nigrostriatal dopaminergic neurodegeneration induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP + in a mouse model of PD. TP5 peptide treatment also blocked dopamine depletion in the striatum and improved gait dysfunction after MPTP administration. The neuroprotective effect of TFP5/TP5 peptide is also associated with marked reduction in neuroinflammation and apoptosis. Here we show inhibition of Cdk5/p25-hyperactivation by TFP5/TP5 peptide, which identifies Cdk5/p25 as a potential therapeutic target to reduce neurodegeneration in PD.

GFAP promoter driven transgenic expression of PDGFB in the mouse brain leads to glioblastoma in a Trp53 null background

NARCIS (Netherlands)

Hede, Sanna-Maria; Hansson, Inga; Afink, Gijs B.; Eriksson, Anna; Nazarenko, Inga; Andrae, Johanna; Genove, Guillem; Westermark, Bengt; Nistér, Monica

2009-01-01

Glioblastomas are the most common and malignant astrocytic brain tumors in human adults. The tumor suppressor gene TP53 is commonly mutated and/or lost in astrocytic brain tumors and the TP53 alterations are often found in combination with excessive growth factor signaling via PDGF/PDGFRalpha. Here,

Long Non-coding RNA, PANDA, Contributes to the Stabilization of p53 Tumor Suppressor Protein.

Science.gov (United States)

Kotake, Yojiro; Kitagawa, Kyoko; Ohhata, Tatsuya; Sakai, Satoshi; Uchida, Chiharu; Niida, Hiroyuki; Naemura, Madoka; Kitagawa, Masatoshi

2016-04-01

P21-associated noncoding RNA DNA damage-activated (PANDA) is induced in response to DNA damage and represses apoptosis by inhibiting the function of nuclear transcription factor Y subunit alpha (NF-YA) transcription factor. Herein, we report that PANDA affects regulation of p53 tumor-suppressor protein. U2OS cells were transfected with PANDA siRNAs. At 72 h post-transfection, cells were subjected to immunoblotting and quantitative reverse transcription-polymerase chain reaction. Depletion of PANDA was associated with decreased levels of p53 protein, but not p53 mRNA. The stability of p53 protein was markedly reduced by PANDA silencing. Degradation of p53 protein by silencing PANDA was prevented by treatment of MG132, a proteasome inhibitor. Moreover, depletion of PANDA prevented accumulation of p53 protein, as a result of DNA damage, induced by the genotoxic agent etoposide. These results suggest that PANDA stabilizes p53 protein in response to DNA damage, and provide new insight into the regulatory mechanisms of p53. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Estrogen receptor positive breast tumors resist chemotherapy by the overexpression of P53 in Cancer Stem Cells

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Fatma Ashour

2018-06-01

Full Text Available Background and Objectives: Breast cancer (BC is classified according to estrogen receptor (ER status into ER+ and ER− tumors. ER+ tumors have a worse response to chemotherapy compared to ER− tumors. BCL-2, TP53, BAX and NF-ΚB are involved in drug resistance in the ER+ tumors. Recently it was shown that Cancer Stem Cells (CSCs play an important role in drug resistance. In this study we tested the hypothesis that CSCs of the ER+ tumors resist drug through the overexpression of BCL-2, TP53, BAX and NF-ΚB. Methods: CSCs were isolated by anoikis resistance assay from MCF7 (ER+ and MDA-MB-231 (ER− cell lines. Isolated CSCs were treated with doxorubicin (DOX and the mRNA expression levels of BCL-2, TP53, BAX and NFKB were investigated by quantitative real time PCR (qPCR with and without treatment. Results: BCL-2, BAX and NF-ΚB showed decreased expression in MCF7 bulk cancer cells after DOX treatment whereas only BCL-2 and BAX showed decreased expression in MDA-MB-231 bulk cancer cells. Interestingly TP53 was the only gene showed a considerable increase in its expression in CSCs of the ER+ MCF7 cell line compared to bulk cancer cells. Moreover, TP53 was the only gene showing exceptionally higher level of expression in MCF7-CSCs compared to MDA-MB-231-CSCs. Conclusion: Our results suggest that CSCs in the ER+ cells escape the effect of DOX treatment by the elevation of p53 expression. Keywords: Breast cancer, Cancer Stem Cells, Drug resistance, Estrogen receptors

Missense mutations located in structural p53 DNA-binding motifs are associated with extremely poor survival in chronic lymphocytic leukemia.

Science.gov (United States)

Trbusek, Martin; Smardova, Jana; Malcikova, Jitka; Sebejova, Ludmila; Dobes, Petr; Svitakova, Miluse; Vranova, Vladimira; Mraz, Marek; Francova, Hana Skuhrova; Doubek, Michael; Brychtova, Yvona; Kuglik, Petr; Pospisilova, Sarka; Mayer, Jiri

2011-07-01

There is a distinct connection between TP53 defects and poor prognosis in chronic lymphocytic leukemia (CLL). It remains unclear whether patients harboring TP53 mutations represent a homogenous prognostic group. We evaluated the survival of patients with CLL and p53 defects identified at our institution by p53 yeast functional assay and complementary interphase fluorescence in situ hybridization analysis detecting del(17p) from 2003 to 2010. A defect of the TP53 gene was identified in 100 of 550 patients. p53 mutations were strongly associated with the deletion of 17p and the unmutated IgVH locus (both P DBMs), structurally well-defined parts of the DNA-binding domain, manifested a clearly shorter median survival (12 months) compared with patients having missense mutations outside DBMs (41 months; P = .002) or nonmissense alterations (36 months; P = .005). The difference in survival was similar in the analysis limited to patients harboring mutation accompanied by del(17p) and was also confirmed in a subgroup harboring TP53 defect at diagnosis. The patients with p53 DBMs mutation (at diagnosis) also manifested a short median time to first therapy (TTFT; 1 month). The substantially worse survival and the short TTFT suggest a strong mutated p53 gain-of-function phenotype in patients with CLL with DBMs mutations. The impact of p53 DBMs mutations on prognosis and response to therapy should be analyzed in investigative clinical trials.

Mitochondrial localization of the low level p53 protein in proliferative cells

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Ferecatu, Ioana; Bergeaud, Marie; Rodriguez-Enfedaque, Aida; Le Floch, Nathalie [Laboratoire de Genetique et Biologie Cellulaire - CNRS UMR 8159, Universite de Versailles Saint-Quentin-en-Yvelines, Versailles, France and Laboratoire de Genetique Moleculaire et Physiologique, Ecole Pratique des Hautes Etudes, Versailles (France); Oliver, Lisa [INSERM U601, Universite de Nantes, Faculte de Medecine, Nantes Cedex (France); Rincheval, Vincent; Renaud, Flore [Laboratoire de Genetique et Biologie Cellulaire - CNRS UMR 8159, Universite de Versailles Saint-Quentin-en-Yvelines, Versailles, France and Laboratoire de Genetique Moleculaire et Physiologique, Ecole Pratique des Hautes Etudes, Versailles (France); Vallette, Francois M. [INSERM U601, Universite de Nantes, Faculte de Medecine, Nantes Cedex (France); Mignotte, Bernard [Laboratoire de Genetique et Biologie Cellulaire - CNRS UMR 8159, Universite de Versailles Saint-Quentin-en-Yvelines, Versailles, France and Laboratoire de Genetique Moleculaire et Physiologique, Ecole Pratique des Hautes Etudes, Versailles (France); Vayssiere, Jean-Luc, E-mail: jean-luc.vayssiere@uvsq.fr [Laboratoire de Genetique et Biologie Cellulaire - CNRS UMR 8159, Universite de Versailles Saint-Quentin-en-Yvelines, Versailles, France and Laboratoire de Genetique Moleculaire et Physiologique, Ecole Pratique des Hautes Etudes, Versailles (France)

2009-10-02

p53 protein plays a central role in suppressing tumorigenesis by inducing cell cycle arrest or apoptosis through transcription-dependent and -independent mechanisms. Emerging publications suggest that following stress, a fraction of p53 translocates to mitochondria to induce cytochrome c release and apoptosis. However, the localization of p53 under unstressed conditions remains largely unexplored. Here we show that p53 is localized at mitochondria in absence of apoptotic stimuli, when cells are proliferating, localization observed in various cell types (rodent and human). This is also supported by acellular assays in which p53 bind strongly to mitochondria isolated from rat liver. Furthermore, the mitochondria subfractionation study and the alkaline treatment of the mitochondrial p53 revealed that the majority of mitochondrial p53 is present in the membranous compartments. Finally, we identified VDAC, a protein of the mitochondrial outer-membrane, as a putative partner of p53 in unstressed/proliferative cells.

Mitochondrial localization of the low level p53 protein in proliferative cells

International Nuclear Information System (INIS)

Ferecatu, Ioana; Bergeaud, Marie; Rodriguez-Enfedaque, Aida; Le Floch, Nathalie; Oliver, Lisa; Rincheval, Vincent; Renaud, Flore; Vallette, Francois M.; Mignotte, Bernard; Vayssiere, Jean-Luc

2009-01-01

p53 protein plays a central role in suppressing tumorigenesis by inducing cell cycle arrest or apoptosis through transcription-dependent and -independent mechanisms. Emerging publications suggest that following stress, a fraction of p53 translocates to mitochondria to induce cytochrome c release and apoptosis. However, the localization of p53 under unstressed conditions remains largely unexplored. Here we show that p53 is localized at mitochondria in absence of apoptotic stimuli, when cells are proliferating, localization observed in various cell types (rodent and human). This is also supported by acellular assays in which p53 bind strongly to mitochondria isolated from rat liver. Furthermore, the mitochondria subfractionation study and the alkaline treatment of the mitochondrial p53 revealed that the majority of mitochondrial p53 is present in the membranous compartments. Finally, we identified VDAC, a protein of the mitochondrial outer-membrane, as a putative partner of p53 in unstressed/proliferative cells.

Immunohistochemical positive stained p53 protein in bladder transitional cell carcinoma

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Halimi Monireh

2009-04-01

Full Text Available Background: Molecular genetics and immunopathologic analysis of bladder cancer have shown some abnormalities in a number of genes and proteins that have been implicated in the development and progression of such tumors, mainly in the p53 pathway. Aims: To investigate the rate of positively stained p53 protein in patients with urothelial papillary carcinoma of the bladder (UCB by immunohistochemistry and its relationship with tumor grade, gender and age of the patients. Settings and Design: During the present cross-sectional study, 100 paraffin-embedded specimens of UCB, which were provided from biopsies of the bladder by transurethral access, were immunohistochemically stained and studied for p53 protein from May 2006 to May 2007 in our referral center pathology laboratory. Materials and Methods: First, 4 µm slices of paraffin sections were provided and then stained by the avidin-biotin peroxidase method. The rate of positively stained p53 protein (defined as positive nuclear staining in over 10% of the cells was assessed. This rate was also estimated and compared between grades, genders and age-related groups (< 70 years, ≥70 years. Statistical Analysis: The χ2 , Fisher′s exact test and Mann-Whitney U test were used for comparing. Results: The overall rate of positively stained specimens was 11% for nuclear p53 protein. This rate was significantly higher in females (10/29 vs. 1/71; P < 0.001; odds ratio [OR]: 0.23; 95% confidence interval [CI]: 4.43-306.08, patients with 70 or older than 70 years (8/42 vs. 3/58; P = 0.04; OR: 0.55; 95% CI: 1.07-17.39 and in high-grade tumors (10/58 vs. 1/42; P = 0.02; OR: 0.59; 95% CI: 0.01-0.95. Conclusions: The rate of positively stained p53 protein for UCB was lower in our population. This rate was also higher in females, patients with 70 or older than 70 years and high grade of UCB.

The expanding regulatory universe of p53 in gastrointestinal cancer.

Science.gov (United States)

Fesler, Andrew; Zhang, Ning; Ju, Jingfang

2016-01-01

Tumor suppresser gene TP53 is one of the most frequently deleted or mutated genes in gastrointestinal cancers. As a transcription factor, p53 regulates a number of important protein coding genes to control cell cycle, cell death, DNA damage/repair, stemness, differentiation and other key cellular functions. In addition, p53 is also able to activate the expression of a number of small non-coding microRNAs (miRNAs) through direct binding to the promoter region of these miRNAs.  Many miRNAs have been identified to be potential tumor suppressors by regulating key effecter target mRNAs. Our understanding of the regulatory network of p53 has recently expanded to include long non-coding RNAs (lncRNAs). Like miRNA, lncRNAs have been found to play important roles in cancer biology.  With our increased understanding of the important functions of these non-coding RNAs and their relationship with p53, we are gaining exciting new insights into the biology and function of cells in response to various growth environment changes. In this review we summarize the current understanding of the ever expanding involvement of non-coding RNAs in the p53 regulatory network and its implications for our understanding of gastrointestinal cancer.

Activation of p53 by nutlin-3a induces apoptosis and cellular senescence in human glioblastoma multiforme.

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Ruth Villalonga-Planells

2011-04-01

Full Text Available Glioblastoma multiforme (GBM is the most common and aggressive primary brain tumor in adults. Despite concerted efforts to improve current therapies and develop novel clinical approaches, patient survival remains poor. As such, increasing attention has focused on developing new therapeutic strategies that specifically target the apoptotic pathway in order to improve treatment responses. Recently, nutlins, small-molecule antagonists of MDM2, have been developed to inhibit p53-MDM2 interaction and activate p53 signaling in cancer cells. Glioma cell lines and primary cultured glioblastoma cells were treated with nutlin-3a. Nutlin-3a induced p53-dependent G1- and G2-M cell cycle arrest and apoptosis in glioma cell lines with normal TP53 status. In addition, nutlin-arrested glioma cells show morphological features of senescence and persistent induction of p21 protein. Furthermore, senescence induced by nutlin-3a might be depending on mTOR pathway activity. In wild-type TP53 primary cultured cells, exposure to nutlin-3a resulted in variable degrees of apoptosis as well as cellular features of senescence. Nutlin-3a-induced apoptosis and senescence were firmly dependent on the presence of functional p53, as revealed by the fact that glioblastoma cells with knockdown p53 with specific siRNA, or cells with mutated or functionally impaired p53 pathway, were completely insensitive to the drug. Finally, we also found that nutlin-3a increased response of glioma cells to radiation therapy. The results provide a basis for the rational use of MDM2 antagonists as a novel treatment option for glioblastoma patients.

Development of Spontaneous Mammary Tumors in BALB/c-p53+-Mice: Detection of Early Genetic Alterations and the Mapping of BALB/c Susceptibility Genes

National Research Council Canada - National Science Library

Blackburn, Anneke

2002-01-01

The TP53 tumor suppressor gene is defective in the majority of sporadic breast cancers, and breast cancer is the most frequent tumor type in women with Li-Fraumeni syndrome who inherit germline mutations in TP53...

Development of Spontaneous Mammary Tumors in BALB/c-p53+/-Mice: Detection of Early Genetic Alterations and the Mapping of BALB/c Susceptibility Genes

National Research Council Canada - National Science Library

Smith, Sallie

2004-01-01

The TP53 tumor suppressor gene is defective in the majority of sporadic breast cancers, and breast cancer is the most frequent tumor type in women with Li-Fraumeni syndrome and bear germline mutations in TP53...

Structure based modification of Bluetongue virus helicase protein VP6 to produce a viable VP6-truncated BTV

Energy Technology Data Exchange (ETDEWEB)

Matsuo, Eiko [Microbiology and Immunology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe-City 657-8501 (Japan); Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom); Leon, Esther; Matthews, Steve J. [Division of Molecular Biosciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom); Roy, Polly, E-mail: polly.roy@lshtm.ac.uk [Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom)

2014-09-05

Highlights: • NMR analysis on BTV VP6 reveals two large loop regions. • The loss of a loop (aa 34–130) does not affect the overall fold of the protein. • A region of VP6 (aa 34–92) is not required for BTV replication. • A region of VP6 (aa 93–130) plays an essential role in the virus replication. - Abstract: Bluetongue virus core protein VP6 is an ATP hydrolysis dependent RNA helicase. However, despite much study, the precise role of VP6 within the viral capsid and its structure remain unclear. To investigate the requirement of VP6 in BTV replication, we initiated a structural and biological study. Multinuclear nuclear magnetic resonance spectra were assigned on his-tagged full-length VP6 (329 amino acid residues) as well as several truncated VP6 variants. The analysis revealed a large structured domain with two large loop regions that exhibit significant conformational exchange. One of the loops (amino acid position 34–130) could be removed without affecting the overall fold of the protein. Moreover, using a BTV reverse genetics system, it was possible to demonstrate that the VP6-truncated BTV was viable in BHK cells in the absence of any helper VP6 protein, suggesting that a large portion of this loop region is not absolutely required for BTV replication.

Gender specific association of TP53 polymorphisms (EX4 215G>C Arg72Pro, IVS3+40-41ins16, and IVS6+62G>A), with risk of oral cancer subtypes and overall survival of the patients.

Science.gov (United States)

Nagam, Srivani L S S; Katta, Saritha; Prasad, Vidudala V T S

2017-03-01

Reports on the association of TP53 polymorphisms with oral cancer are not only limited but also not specific to site and/or gender. Hence, we examined the effect of TP53 polymorphisms (EX4 215G>C, IVS3+40-41ins16 and IVS6+62G>A) on buccal mucosa cancer (BMC) and tongue cancer (TC) risk, survival of patients in relation to risk and clinical factors, gender wise (excepting for estimating hazards ratio [HR]), using Fisher's Exact Test, Kaplan-Meier analysis, and Cox-proportional hazards models. The exonic polymorphism increased BMC and TC risk in males by 2-4-fold. The IVS3+40-41ins16 was protective against BMC and TC in both genders, whereas IVS6+62G>A protected only males against TC. Genotype combinations and haplotypes which altered the risk of cancers in males and females were different. TC males, aged 40-44 years and females, aged 55-59 years survived better than BMC patients. The IVS3+40-41ins16 polymorphism differentially impacted survival of female patients exposed to tobacco. TC patients with EX4 215GC with lymphovascular spread (LVS) and metastasis exhibited higher HR while, patients with EX4 215CC and perineural invasion (PNI) showed lower HR. Impact of the intronic variants along with clinical parameters on survival and HR estimates varied between BMC and TC. Our bioinformatics analysis revealed the presence of CTCF binding site within TP53 gene. In conclusion, the polymorphisms altered risk and survival of BMC and TC in a gender specific manner, which varied with mode of tobacco and/or alcohol use. The current study, therefore underscores strong need for research, stratified by tumor site and gender. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

No evidence that protein truncating variants in BRIP1 are associated with breast cancer risk: implications for gene panel testing

OpenAIRE

Easton, Douglas Frederick; Lesueur, Fabienne; Decker, Brennan; Michailidou, Kyriaki; Li, Jun; Allen, Jamie; Luccarini, Craig; Pooley, Karen Anne; Shah, Mitulkumar Nandlal; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; Ahmad, Jamil; Thompson, Ella R; Damiola, Francesca

2016-01-01

Background BRCA1 interacting protein C-terminal helicase 1 (BRIP1) is one of the Fanconi Anaemia Complementation (FANC) group family of DNA repair proteins. Biallelic mutations in BRIP1 are responsible for FANC group J, and previous studies have also suggested that rare protein truncating variants in BRIP1 are associated with an increased risk of breast cancer. These studies have led to inclusion of BRIP1 on targeted sequencing panels for breast cancer risk prediction. Metho...

Evaluation of Single Nucleotide Polymorphisms (SNPs) in the p53 Binding Protein 1 (TP53BP1) Gene in Breast Cancer Patients Treated With Breast-Conserving Surgery and Whole-Breast Irradiation (BCS + RT)

International Nuclear Information System (INIS)

Haffty, Bruce G.; Goyal, Sharad; Kulkarni, Diptee; Green, Camille; Vazquez, Alexi; Schiff, Devora; Moran, Meena S.; Yang Qifeng; Ganesan, Shridar; Hirsfield, Kim M.

2011-01-01

Purpose: TP53BP1 is a key component of radiation-induced deoxyribonucleic acid damage repair. The purpose of this study was to evaluate the significance of a known common single nucleotide polymorphism in this gene (rs560191) in patients treated with breast-conserving surgery and whole-breast irradiation (BCS + RT). Methods and Materials: The population consisted of 176 premenopausal women treated with BCS + RT (median follow-up, 12 years). Genomic deoxyribonucleic acid was processed by use of TaqMan assays. Each allele for rs560191 was either C or G, so each patient was therefore classified as CC, CG, or GG. Patients were grouped as GG if they were homozygous for the variant G allele or CC-CG if they carried at least one copy of the common C allele (CC or CG). Results: Of the 176 women, 124 (71%) were CC-CG and 52 (29%) were GG. The mean age was 44 years for GG vs. 38 years for CC-CG (p < 0.001). GG was more common in African-American women than white women (69% vs. 13%, p < 0.001) and more commonly estrogen receptor negative (70% vs. 49%, p = 0.02). There were no significant correlations of rs560191 with other critical variables. Despite the fact that GG patients were older, the 10-year rate of local relapses was higher (22% for GG vs. 12% for CC-CG, p = 0.04). Conclusions: This novel avenue of investigation of polymorphisms in radiation repair/response genes in patients treated with BCS + RT suggests a correlation to local relapse. Additional evaluation is needed to assess the biological and functional significance of these single nucleotide polymorphisms, and larger confirmatory validation studies will be required to determine the clinical implications.

Stress Hormone Cortisol Enhances Bcl2 Like-12 Expression to Inhibit p53 in Hepatocellular Carcinoma Cells.

Science.gov (United States)

Wu, Weizhong; Liu, Sanguang; Liang, Yunfei; Zhou, Zegao; Bian, Wei; Liu, Xueqing

2017-12-01

The pathogenesis of hepatocellular carcinoma (HC) is unclear. It is suggested that psychological stress associates with the pathogenesis of liver cancer. Bcl2-like protein 12 (Bcl2L12) suppresses p53 protein. This study tests a hypothesis that the major stress hormone, cortisol, inhibits the expression of p53 in HC cells (HCC) via up regulating the expression of Bcl2L12. Peripheral blood samples were collected from patients with HC to be analyzed for the levels of cortisol. HCC were cultured to assess the role of cortisol in the regulation of the expression of Bcl2L12 and p53 in HCC. We observed that the serum cortisol levels were higher in HC patients. Expression of Bcl2L12 in HCC was correlated with serum cortisol. Cortisol enhanced the Bcl2L12 expression in HCC. Bcl2L12 binding to the TP53 promoter was correlated with p53 expression in HCC. Cortisol increased the Bcl2L12 expression in HCC to inhibit p53 expression. Stress hormone cortisol suppresses p53 in HCC via enhancing Bcl2L12 expression in HCC. The results suggest that cortisol may be a therapeutic target for the treatment of HC.

Análise comparativa da imunoexpressão da proteína p53 (clones DO-7 e PAb-240 em carcinomas de células escamosas intrabucais e labiais Comparative analysis of p53 protein immunostaining (antibodies DO-7 and PAb-240 in oral cavity and lip squamous cell carcinomas

Directory of Open Access Journals (Sweden)

José de Assis Silva Júnior

2009-08-01

.BACKGROUND: Carcinogenesis is a multifactorial process and inactivation of p53 protein is a genetic change commonly observed in oral squamous cell carcinomas (OSCC. OBJECTIVES: To analyze and compare the expression of p53 protein through antibodies DO-7 and PAb-240 in OSCC samples located in the oral cavity and lower lip. MATERIAL AND METHODS: Forty cases of OSCC were selected and divided into oral cavity and lower lip groups (20 cases each. Immunohistochemical technique was performed using antibodies DO-7 and PAb-240. Quantification of the cases was performed through digital image analysis and underwent specific statistical treatments. RESULTS: Expression of p53 protein was verified with DO-7 antibody in 13 cases (65% of oral cavity carcinomas and in 19 cases (95% of lower lip carcinoma. PAb-240 positivity was detected in 9 cases (45% of oral cavity lesions and in 15 cases (75% located in the lower lip. According to Mann-Whitney test, there were no statistically significant differences between the expressions of p53 protein in both groups, regardless of the antibody used. According to Wilcoxon test, there were statistically significant differences between the expression of DO-7 antibody and PAb-240 in each of the analyzed groups (p-value = 0.013; lower lip p-value = 0.016 - oral cavity. CONCLUSIONS: The expression of p53 protein was observed both in the oral cavity and lip OSCC, which suggests the occurrence of mutations in TP53 gene. The quantitative differences between the antibodies studied, regardless of the site of the lesions, reflect different specificity between clones DO-7 and PAb-240. Further studies are required to establish the best antibody for p53 protein in oral squamous cell carcinomas.

A Novel Protein Interaction between Nucleotide Binding Domain of Hsp70 and p53 Motif

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Asita Elengoe

2015-01-01

Full Text Available Currently, protein interaction of Homo sapiens nucleotide binding domain (NBD of heat shock 70 kDa protein (PDB: 1HJO with p53 motif remains to be elucidated. The NBD-p53 motif complex enhances the p53 stabilization, thereby increasing the tumor suppression activity in cancer treatment. Therefore, we identified the interaction between NBD and p53 using STRING version 9.1 program. Then, we modeled the three-dimensional structure of p53 motif through homology modeling and determined the binding affinity and stability of NBD-p53 motif complex structure via molecular docking and dynamics (MD simulation. Human DNA binding domain of p53 motif (SCMGGMNR retrieved from UniProt (UniProtKB: P04637 was docked with the NBD protein, using the Autodock version 4.2 program. The binding energy and intermolecular energy for the NBD-p53 motif complex were −0.44 Kcal/mol and −9.90 Kcal/mol, respectively. Moreover, RMSD, RMSF, hydrogen bonds, salt bridge, and secondary structure analyses revealed that the NBD protein had a strong bond with p53 motif and the protein-ligand complex was stable. Thus, the current data would be highly encouraging for designing Hsp70 structure based drug in cancer therapy.

Use of the integration elements encoded by the temperate lactococcal bacteriophage TP901-1

DEFF Research Database (Denmark)

Brøndsted, Lone; Hammer, Karin

1999-01-01

Previously we showed that only one phage-expressed protein (Orf1), a 425-bp region upstream of the orf1 gene (presumably encoding a promoter), and the attP region are necessary and also sufficient for integration of the bacteriophage TP901-1 genome into the chromosome of Lactococcus lactis subsp......P region seem to be necessary for site-specific integration of the temperate bacteriophage TP901-1. By use of the integrative elements (attP and orf1) expressed by the temperate lactococcal bacteriophage TP901-1, a system for obtaining stable chromosomal single-copy transcriptional fusions in L. lactis...

Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer

International Nuclear Information System (INIS)

Tsutsui, Shinichi; Yasuda, Kazuhiro; Suzuki, Kosuke; Takeuchi, Hideya; Nishizaki, Takashi; Higashi, Hidefumi; Era, Shoichi

2006-01-01

Recent experimental studies have shown that Bcl-2, which has been established as a key player in the control of apoptosis, plays a role in regulating the cell cycle and proliferation. The aim of this study was to investigate the relationship between Bcl-2 and p27 protein expression, p53 protein expression and the proliferation activity as defined by the MIB-1 counts. The prognostic implication of Bcl-2 protein expression in relation to p27 and p53 protein expressions and MIB-1 counts for breast cancer was also evaluated. The immunohistochemical expression of Bcl-2 protein was evaluated in a series of 249 invasive ductal carcinomas of the breast, in which p27 and p53 protein expressions and MIB-1 counts had been determined previously. The Bcl-2 protein expression was found to be decreased in 105 (42%) cases. A decreased Bcl-2 protein expression was significantly correlated with a nuclear grade of III, a negative estrogen receptor, a decreased p27 protein expression, a positive p53 protein expression, positive MIB-1 counts and a positive HER2 protein expression. The incidence of a nuclear grade of III and positive MIB-1 counts increased as the number of abnormal findings of Bcl-2, p27 and p53 protein expressions increased. A univariate analysis indicated a decreased Bcl-2 protein expression to be significantly (p = 0.0089) associated with a worse disease free survival (DFS), while a multivariate analysis indicated the lymph node status and MIB-1 counts to be independently significant prognostic factors for the DFS. The Bcl-2 protein expression has a close correlation with p27 and p53 protein expressions and the proliferation activity determined by MIB-1 counts in invasive ductal carcinoma of the breast. The prognostic value of Bcl-2 as well as p27 and p53 protein expressions was dependent on the proliferation activity in breast cancer

Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer

Directory of Open Access Journals (Sweden)

Nishizaki Takashi

2006-07-01

Full Text Available Abstract Background Recent experimental studies have shown that Bcl-2, which has been established as a key player in the control of apoptosis, plays a role in regulating the cell cycle and proliferation. The aim of this study was to investigate the relationship between Bcl-2 and p27 protein expression, p53 protein expression and the proliferation activity as defined by the MIB-1 counts. The prognostic implication of Bcl-2 protein expression in relation to p27 and p53 protein expressions and MIB-1 counts for breast cancer was also evaluated. Methods The immunohistochemical expression of Bcl-2 protein was evaluated in a series of 249 invasive ductal carcinomas of the breast, in which p27 and p53 protein expressions and MIB-1 counts had been determined previously. Results The Bcl-2 protein expression was found to be decreased in 105 (42% cases. A decreased Bcl-2 protein expression was significantly correlated with a nuclear grade of III, a negative estrogen receptor, a decreased p27 protein expression, a positive p53 protein expression, positive MIB-1 counts and a positive HER2 protein expression. The incidence of a nuclear grade of III and positive MIB-1 counts increased as the number of abnormal findings of Bcl-2, p27 and p53 protein expressions increased. A univariate analysis indicated a decreased Bcl-2 protein expression to be significantly (p = 0.0089 associated with a worse disease free survival (DFS, while a multivariate analysis indicated the lymph node status and MIB-1 counts to be independently significant prognostic factors for the DFS. Conclusion The Bcl-2 protein expression has a close correlation with p27 and p53 protein expressions and the proliferation activity determined by MIB-1 counts in invasive ductal carcinoma of the breast. The prognostic value of Bcl-2 as well as p27 and p53 protein expressions was dependent on the proliferation activity in breast cancer.

Frequent mutations in EGFR, KRAS and TP53 genes in human lung cancer tumors detected by ion torrent DNA sequencing.

Directory of Open Access Journals (Sweden)

Xin Cai

Full Text Available Lung cancer is the most common malignancy and the leading cause of cancer deaths worldwide. While smoking is by far the leading cause of lung cancer, other environmental and genetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive lung cancer molecular profile is essential for developing more effective, tailored therapies. Until recently, personalized DNA sequencing to identify genetic mutations in cancer was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 76 human lung cancer samples. The sequencing analysis revealed missense mutations in KRAS, EGFR, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.

Protein: FBA7 [TP Atlas

Lifescience Database Archive (English)

Full Text Available FBA7 claudin-zona occluden Tjp1 Zo1 Tight junction protein ZO-1 Tight junction protein 1, Zona occludens pr...otein 1, Zonula occludens protein 1 10090 Mus musculus 21872 P39447 2RRM P39447 21431884 ...

Polycomb Group Protein PHF1 Regulates p53-dependent Cell Growth Arrest and Apoptosis*

Science.gov (United States)

Yang, Yang; Wang, Chenji; Zhang, Pingzhao; Gao, Kun; Wang, Dejie; Yu, Hongxiu; Zhang, Ting; Jiang, Sirui; Hexige, Saiyin; Hong, Zehui; Yasui, Akira; Liu, Jun O.; Huang, Haojie; Yu, Long

2013-01-01

Polycomb group protein PHF1 is well known as a component of a novel EED-EZH2·Polycomb repressive complex 2 complex and plays important roles in H3K27 methylation and Hox gene silencing. PHF1 is also involved in the response to DNA double-strand breaks in human cells, promotes nonhomologous end-joining processes through interaction with Ku70/Ku80. Here, we identified another function of PHF1 as a potential p53 pathway activator in a pathway screen using luminescence reporter assay. Subsequent studies showed PHF1 directly interacts with p53 proteins both in vivo and in vitro and co-localized in nucleus. PHF1 binds to the C-terminal regulatory domain of p53. Overexpression of PHF1 elevated p53 protein level and prolonged its turnover. Knockdown of PHF1 reduced p53 protein level and its target gene expression both in normal state and DNA damage response. Mechanically, PHF1 protects p53 proteins from MDM2-mediated ubiquitination and degradation. Furthermore, we showed that PHF1 regulates cell growth arrest and etoposide-induced apoptosis in a p53-dependent manner. Finally, PHF1 expression was significantly down-regulated in human breast cancer samples. Taken together, we establish PHF1 as a novel positive regulator of the p53 pathway. These data shed light on the potential roles of PHF1 in tumorigenesis and/or tumor progression. PMID:23150668

Digestion proteomics: tracking lactoferrin truncation and peptide release during simulated gastric digestion.

Science.gov (United States)

Grosvenor, Anita J; Haigh, Brendan J; Dyer, Jolon M

2014-11-01

The extent to which nutritional and functional benefit is derived from proteins in food is related to its breakdown and digestion in the body after consumption. Further, detailed information about food protein truncation during digestion is critical to understanding and optimising the availability of bioactives, in controlling and limiting allergen release, and in minimising or monitoring the effects of processing and food preparation. However, tracking the complex array of products formed during the digestion of proteins is not easily accomplished using classical proteomics. We here present and develop a novel proteomic approach using isobaric labelling to mapping and tracking protein truncation and peptide release during simulated gastric digestion, using bovine lactoferrin as a model food protein. The relative abundance of related peptides was tracked throughout a digestion time course, and the effect of pasteurisation on peptide release assessed. The new approach to food digestion proteomics developed here therefore appears to be highly suitable not only for tracking the truncation and relative abundance of released peptides during gastric digestion, but also for determining the effects of protein modification on digestibility and potential bioavailability.

Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

Science.gov (United States)

Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

1992-07-15

Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance.

Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

Science.gov (United States)

Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

1992-01-01

Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance. Images PMID:1631137

Evaluation of Tp-e interval and Tp-e/QT ratio in patients with non-dipper hypertension.

Science.gov (United States)

Demir, Mehmet; Uyan, Umut

2014-01-01

Non-dipper hypertension is associated with increased cardiovascular morbidity and mortality. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate ventricular repolarization by using Tp-e interval and Tp-e/QT ratio in patients with non-dipper hypertension. This study included 80 hypertensive patients. Hypertensive patients were divided into two groups: 50 dipper patients (29 male, mean age 51.5 ± 8 years) and 30 non-dipper patients (17 male, mean age 50.6 ± 5.4 years). Tp-e interval and Tp-e/QT ratio were measured from the 12-lead electrocardiogram. These parameters were compared between groups. No statistically significant difference was found between two groups in terms of basic characteristics. In electrocardiographic parameters analysis, QT dispersion (QTd) and corrected QTd were significantly increased in non-dipper patients compared to the dippers (39.4 ± 11.5 versus 27.3 ± 7.5 ms and 37.5 ± 9.5 versus 29.2 ± 6.5 ms, p = 0.001 and p = 0.01, respectively). Tp-e interval and Tp-e/QT ratio were also significantly higher in non-dipper patients (97.5 ± 11.2 versus 84.2 ± 8.3 ms and 0.23 ± 0.02 versus 0.17 ± 0.02, all p value ratio are prolonged in patients with non-dipper hypertension.

Protein: FEA3 [TP Atlas

Lifescience Database Archive (English)

Full Text Available FEA3 AREB pathway: Signaling proteins At4g11890/T26M18_100 At4g11890, Protein kinase family pr...otein, Putative uncharacterized protein At4g11890/T26M18_100 3702 Arabidopsis thaliana 826796 Q8GY82 22225700 ...

The p53 serology is predictive of the response to the pre surgery radio chemotherapy in the oesophagus cancers

International Nuclear Information System (INIS)

Metges, J.P.; Giroux, M.A.; Volant, A.; Morin, J.F.; Malhaire, J.P.; Gouerou, H.; Ferec, C.; Robaskiewicz, M.; Labat, J.P.

1997-01-01

The mutations of the TP 53 and MTS1 (p16) gene have been described in numerous neoplasms but their relation with a response to the treatment is still little described. The aim of this work was to evaluate the value of the p53 status(serology, immunohistochemistry and molecular biology) and of the MTS1 gene( protein p16) for the response to the pre surgery radio chemotherapy in a troop of patients suffering from esophagus epidermoid cancer. The p53 serology is positive in 40% of cases and is statistically associated to a bad response. The lost of alleles for MTS1 has been found in 20% of cases but non predictive to the response. A prospective study would be interesting. (N.C.)

Frequency of p53 Gene Mutation and Protein Expression in Oral Squamous Cell Carcinoma

International Nuclear Information System (INIS)

Ara, N.; Atique, M.; Ahmed, S.; Bukhari, S. G. A.

2014-01-01

Objective: To determine the frequency of p53 gene mutation and protein expression in Oral Squamous Cell Carcinoma (OSCC) and to establish correlation between the two. Study Design: Analytical study. Place and Duration of Study: Histopathology Department and Molecular Biology Laboratory, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from May 2010 to May 2011. Methodology: Thirty diagnosed cases of OSCC were selected by consecutive sampling. Seventeen were retrieved from the record files of the AFIP, and 13 fresh/frozen sections were selected from patients reporting to the Oral Surgery Department, Armed Forces Institute of Dentistry (AFID). Gene p53 mutation was analyzed in all the cases using PCRSSCP analysis. DNA was extracted from the formalin-fixed and paraffin-embedded tissue sections and fresh/frozen sections. DNA thus extracted was amplified by polymerase chain reaction. The amplified products were denatured and finally analyzed by gel electrophoresis. Gene mutation was detected as electrophoretic mobility shift. The immunohistochemical marker p53 was applied to the same 30 cases and overexpression of protein p53 was recorded. Results: Immunohistochemical expression of marker p53 was positive in 67% (95% Confidence Interval (CI) 48.7 - 80.9) of the cases. Mutations of the p53 gene were detected in 23% (95% CI 11.5 - 41.2) of the OSCC. No statistically significant correlation was found between p53 gene mutation and protein p53 expression (rs = - 0.057, p = 0.765). Conclusion: A substantial number of patients have p53 gene mutation (23%) and protein p53 expression (67%) in oral squamous cell carcinoma (OSCC). (author)

Differential protein expression, DNA binding and interaction with SV40 large tumour antigen implicate the p63-family of proteins in replicative senescence.

Science.gov (United States)

Djelloul, Siham; Tarunina, Marina; Barnouin, Karin; Mackay, Alan; Jat, Parmjit S

2002-02-07

P53 activity plays a key role in mammalian cells when they undergo replicative senescence at their Hayflick limit. To determine whether p63 proteins, members of the family of p53-related genes, are also involved in this process, we examined their expression in serially passaged rat embryo fibroblasts. Upon senescence, two truncated DeltaNp63 proteins decreased in abundance whereas two TAp63 isoforms accumulated. 2-D gel analysis showed that the DeltaNp63 proteins underwent post-translational modifications in both proliferating and senescent cells. Direct binding of DeltaNp63 proteins to a p53 consensus motif was greater in proliferating cells than senescent cells. In contrast p63alpha isoforms bound to DNA in a p53 dependent manner and this was higher in senescent cells than proliferating cells. An interaction of p63alpha proteins with SV40 large tumour antigen was also detected and ectopic expression of DeltaNp63alpha can extend the lifespan of rat embryo fibroblasts. Taken together the results indicate that p63 proteins may play a role in replicative senescence either by competition for p53 DNA binding sites or by direct interaction with p53 protein bound to DNA.

Regulatory module involving FGF13, miR-504, and p53 regulates ribosomal biogenesis and supports cancer cell survival

Science.gov (United States)

Bublik, Débora R.; Bursać, Slađana; Sheffer, Michal; Oršolić, Ines; Shalit, Tali; Tarcic, Ohad; Kotler, Eran; Mouhadeb, Odelia; Hoffman, Yonit; Fuchs, Gilad; Levin, Yishai; Volarević, Siniša; Oren, Moshe

2017-01-01

The microRNA miR-504 targets TP53 mRNA encoding the p53 tumor suppressor. miR-504 resides within the fibroblast growth factor 13 (FGF13) gene, which is overexpressed in various cancers. We report that the FGF13 locus, comprising FGF13 and miR-504, is transcriptionally repressed by p53, defining an additional negative feedback loop in the p53 network. Furthermore, we show that FGF13 1A is a nucleolar protein that represses ribosomal RNA transcription and attenuates protein synthesis. Importantly, in cancer cells expressing high levels of FGF13, the depletion of FGF13 elicits increased proteostasis stress, associated with the accumulation of reactive oxygen species and apoptosis. Notably, stepwise neoplastic transformation is accompanied by a gradual increase in FGF13 expression and increased dependence on FGF13 for survival (“nononcogene addiction”). Moreover, FGF13 overexpression enables cells to cope more effectively with the stress elicited by oncogenic Ras protein. We propose that, in cells in which activated oncogenes drive excessive protein synthesis, FGF13 may favor survival by maintaining translation rates at a level compatible with the protein quality-control capacity of the cell. Thus, FGF13 may serve as an enabler, allowing cancer cells to evade proteostasis stress triggered by oncogene activation. PMID:27994142

Protein: FBA3 [TP Atlas

Lifescience Database Archive (English)

Full Text Available FBA3 Ubiquitination CBLB RNF56 CBLB E3 ubiquitin-protein ligase CBL-B Casitas B-lineage lymphoma pr...oto-oncogene b, RING finger protein 56, SH3-binding protein CBL-B, Signal transduction prote

Synergistic effect of p53 on TSA-induced stanniocalcin 1 expression in human nasopharyngeal carcinoma cells, CNE2.

Science.gov (United States)

Ching, L Y; Yeung, Bonnie H Y; Wong, Chris K C

2012-06-01

Human stanniocalcin 1 (STC1) has recently been identified as a putative protein factor involved in cellular apoptosis. The use of histone deacetylase inhibitor (i.e. trichostatin A (TSA)) and doxorubicin (Dox) is one of the common treatment methods to induce apoptosis in human cancer cells. A study on TSA and Dox-mediated apoptosis may shed light on the regulation and function of STC1 in cancer treatment. In this study, TSA and Dox cotreatment in human nasopharyngeal carcinoma cells (CNE2) elicited synergistic effects on STC1 gene expression and cellular apoptosis. An activation of p53 (TP53) transcriptional activity in Dox- or Dox+TSA-treated cells was revealed by the increased expression levels of p53 mRNA/protein as well as p53-driven luciferase activities. To elucidate the possible involvement of p53 in STC1 gene transcription, a vector expressing wild-type or dominant negative (DN) p53 was transiently transfected into the cells. Both STC1 promoter luciferase constructs and chromatin immunoprecipitation assays did not support the direct role of p53 in STC1 gene transactivation. However, the synergistic effects of p53 on the induction of NF-κB phosphorylation and the recruitment of acetylated histone H3 in STC1 promoter were observed in TSA-cotreated cells. The overexpression of exogenous STC1 sensitized apoptosis in Dox-treated cells. Taken together, this study provides data to show the cross talk of NF-κB, p53, and histone protein in the regulation of STC1 expression and function.

Protein: MPB2 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPB2 Ubiquitin ligases WWP1 WWP1 NEDD4-like E3 ubiquitin-protein ligase WWP1 Atrophin-1-interacting pr...otein 5, WW domain-containing protein 1 9606 Homo sapiens Q9H0M0 11059 2OP7, 1ND7 11059 ...

Influence of x-rays and UV-light on the presence of oncogene proteins in spleen cells of leukemic mice

International Nuclear Information System (INIS)

Popovic Hadzija, M.; Poljak Blazi, M.

1996-01-01

Proto-oncogenes are involved in growth, defferentiation and proliferation of normal cells, and in process of neoplastic transformation. In genome of normal cells, exist also tumor-suppressor genes, which contribute to cancer when they are inactivated. Those genes are target for carcinogenesis provoked by radiation. However, species specific genetic factors are important in determing which, if any, gene will be transformed by radiation. It is possible to presume that oncogenes are involved in the development of radioresistant phenotype of ML. Because of that, we examined the presence of c-myc protein in ML cells during the growth of ML and after the irradiation of these cells. Also, we examined the presence of tumor-suppressor protein p53, because inactivation or loss of p53 gene is in connection with transformation of cells. ML is strain specific for RFM mice. Spleen cells were tested 9 (nonterminal phase NTP) or 12 days (terminal phase TP) after inoculation of ML. Cells from NTP were also irradiate with x-rays or UV-light. C-myc protein expresse 74.98% spleen cells of healthy RFM mice. Wild type of p53 protein was detected in 60% of these cells, but mp53 was found in only 5.3% of cells. These results could be explained by the role of c-myc and p53 proteins in regulation of biologic processes. A few spleen cells of NTP expressed c-myc (15%) and mp53 (9.6%) proteins. But, in the same phase higher expressions of wp53 protein (30.5%) was found. On the other hand, the number of c-myc positive cells in TP of leukemia explanation lies in connection of c-myc protein and process of programmed cell death (apoptosis). During growth of ML the number of mp53 positive cells increased (to 47.8%), but wp53 positive cells decreased (to13.4%9). Both types of irradiation provoked strong activation of cellular c-myc gene in ML cells of NTP. We found about 95% c-myc positive cells after x-rays and 93% after UV-light

Study of p53 protein expression levels from irradiated peripheral blood lymphocytes for biodosimetry

International Nuclear Information System (INIS)

Cavalcanti, M.B.; Fernandes, T.S.; Melo, J.A.; Neves, M.A.B.; Machado, C.G.F

2005-01-01

Biodosimetry can be defined as the investigation of radioinduced biological effects in order to correlate them with the absorbed dose. Scoring of unstable chromosomal aberrations and micronuclei, from in vitro irradiated peripheral blood lymphocytes, is commonly used for biodosimetry based on cytogenetic analysis. However, this method of analysis is time-consuming, which may represent a pitfall when fast investigation of a possible exposure to ionizing radiation (IR) is needed. The interaction of IR with the living cell can cause injuries in the DNA molecules. However, normal cells possess mechanisms of repair that are capable to correct those damages. During the repair process of the DNA various proteins are expressed. Among these proteins, p53 plays an important role. This protein is a transcription factor that helps in the maintenance of the genomic integrity. p53 protein is found into the cytoplasm in reduced concentrations and has a short average life. However, expression of p53 protein can be induced by DNA harmful radioinduced, which increases the concentration and the average life of this protein, making possible its detection. Thus, the correlation between the increasing of p53 expression and the irradiation may constitute a fast and reliable method of individual monitoring in cases of accidental or suspected exposures to IR. In this context, the objective of this research was to evaluate the p53 protein expression levels from lymphocytes of the human peripheral blood after in vitro irradiation. For this, samples of peripheral blood from healthy individuals were irradiated with known doses. Lymphocytes were separated on ficoll gradient by centrifugation and re-suspended at 1x 10 6 /mL in RPMI medium enriched with fetal calf serum. Hence, lymphocytes were incubated in 5% CO 2 at 37 deg C prior to the methodology of flow cytometry, using intranuclear antigens for the quantification of p53. In this report, the methodology performed and the results obtained

Study of p53 protein expression levels from irradiated peripheral blood lymphocytes for biodosimetry

Energy Technology Data Exchange (ETDEWEB)

Cavalcanti, M.B.; Fernandes, T.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Amaral, A. [Universite Paris XII (UPXII) (France); Melo, J.A. [Centro de Radioterapia de Pernambuco (CERAPE), PE (Brazil); Neves, M.A.B.; Machado, C.G.F, E-mail: maribrayner@yahoo.com.br [Fundacao de Hematologia e Hemoterapia de Pernambuco, PE (Brazil)

2005-07-01

Biodosimetry can be defined as the investigation of radioinduced biological effects in order to correlate them with the absorbed dose. Scoring of unstable chromosomal aberrations and micronuclei, from in vitro irradiated peripheral blood lymphocytes, is commonly used for biodosimetry based on cytogenetic analysis. However, this method of analysis is time-consuming, which may represent a pitfall when fast investigation of a possible exposure to ionizing radiation (IR) is needed. The interaction of IR with the living cell can cause injuries in the DNA molecules. However, normal cells possess mechanisms of repair that are capable to correct those damages. During the repair process of the DNA various proteins are expressed. Among these proteins, p53 plays an important role. This protein is a transcription factor that helps in the maintenance of the genomic integrity. p53 protein is found into the cytoplasm in reduced concentrations and has a short average life. However, expression of p53 protein can be induced by DNA harmful radioinduced, which increases the concentration and the average life of this protein, making possible its detection. Thus, the correlation between the increasing of p53 expression and the irradiation may constitute a fast and reliable method of individual monitoring in cases of accidental or suspected exposures to IR. In this context, the objective of this research was to evaluate the p53 protein expression levels from lymphocytes of the human peripheral blood after in vitro irradiation. For this, samples of peripheral blood from healthy individuals were irradiated with known doses. Lymphocytes were separated on ficoll gradient by centrifugation and re-suspended at 1x 10{sub 6}/mL in RPMI medium enriched with fetal calf serum. Hence, lymphocytes were incubated in 5% CO{sub 2} at 37 deg C prior to the methodology of flow cytometry, using intranuclear antigens for the quantification of p53. In this report, the methodology performed and the results

Protein: FBA8 [TP Atlas

Lifescience Database Archive (English)

Full Text Available FBA8 LUBAC (linear ubiquitin chain-assembly complex) RNF31 ZIBRA RNF31 RING finger pr...otein 31 HOIL-1-interacting protein, Zinc in-between-RING-finger ubiquitin-associated domain protein 9606 Homo sapiens Q96EP0 55072 2CT7 55072 Q96EP0 ...

Protein: MPA1 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPA1 TLR signaling molecules MAVS IPS1, KIAA1271, VISA VISA_(gene) Mitochondrial antiviral-signaling pr...otein CARD adapter inducing interferon beta, Interferon beta promoter stimulator protein... 1, Putative NF-kappa-B-activating protein 031N, Virus-induced-signaling adapter 9606 Homo sapiens Q7Z434 57506 2VGQ 57506 ...

Analysis of the collar-whisker structure of temperate lactococcal bacteriophage TP901-1

DEFF Research Database (Denmark)

Vegge, Christina Skovgaard; Neve, Horst; Brøndsted, Lone

2006-01-01

Proteins homologous to the protein NPS (neck passage structure) are widespread among lactococcal phages. We investigated the hypothesis that NPS is involved in the infection of phage TP901-1 by analysis of an NPS mutant. NPS was determined to form a collar-whisker complex but was shown to be none...

Expression and characterization of truncated human heme oxygenase (hHO-1) and a fusion protein of hHO-1 with human cytochrome P450 reductase.

Science.gov (United States)

Wilks, A; Black, S M; Miller, W L; Ortiz de Montellano, P R

1995-04-04

A human heme oxygenase (hHO-1) gene without the sequence coding for the last 23 amino acids has been expressed in Escherichia coli behind the pho A promoter. The truncated enzyme is obtained in high yields as a soluble, catalytically-active protein, making it available for the first time for detailed mechanistic studies. The purified, truncated hHO-1/heme complex is spectroscopically indistinguishable from that of the rat enzyme and converts heme to biliverdin when reconstituted with rat liver cytochrome P450 reductase. A self-sufficient heme oxygenase system has been obtained by fusing the truncated hHO-1 gene to the gene for human cytochrome P450 reductase without the sequence coding for the 20 amino acid membrane binding domain. Expression of the fusion protein in pCWori+ yields a protein that only requires NADPH for catalytic turnover. The failure of exogenous cytochrome P450 reductase to stimulate turnover and the insensitivity of the catalytic rate toward changes in ionic strength establish that electrons are transferred intramolecularly between the reductase and heme oxygenase domains of the fusion protein. The Vmax for the fusion protein is 2.5 times higher than that for the reconstituted system. Therefore, either the covalent tether does not interfere with normal docking and electron transfer between the flavin and heme domains or alternative but equally efficient electron transfer pathways are available that do not require specific docking.

Structural Biology of CI from Phage TP901-1

DEFF Research Database (Denmark)

Rasmussen, Kim Krighaar

(CTD), separated by a linker of various lengths. The NTD is responsible for DNA binding and the CTD is responsible for oligomerization of the CI protein. A Helix-turn-Helix motif is usually responsible for DNA binding. This thesis presents a structural characterization of the CI repressor from TP901...... condition of the CTD, responsible for the arrangement of the hexameric CI repressor. The arrangement of the CI repressor for TP901-1 has previously been described to have 32 point group symmetry based on SAXS studies. The CTD crystallizes with P3121 or P3221 symmetry with one molecule in the asymmetric unit......-length CI can only be answered unambiguously by solving the CTD crystal structure or by use of alternative techniques on the full-length CI....

The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

Science.gov (United States)

Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

2014-02-01

Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

Further Confirmation of Germline Glioma Risk Variant rs78378222 in TP53 and Its Implication in Tumor Tissues via Integrative Analysis of TCGA Data

Science.gov (United States)

Wang, Zhaoming; Rajaraman, Preetha; Melin, Beatrice S.; Chung, Charles C.; Zhang, Weijia; McKean-Cowdin, Roberta; Michaud, Dominique; Yeager, Meredith; Ahlbom, Anders; Albanes, Demetrius; Andersson, Ulrika; Beane Freeman, Laura E.; Buring, Julie E.; Butler, Mary Ann; Carreón, Tania; Feychting, Maria; Gapstur, Susan M.; Gaziano, J. Michael; Giles, Graham G.; Hallmans, Goran; Henriksson, Roger; Hoffman-Bolton, Judith; Inskip, Peter D.; Kitahara, Cari M.; Le Marchand, Loic; Linet, Martha S.; Li, Shengchao; Peters, Ulrike; Purdue, Mark P.; Rothman, Nathaniel; Ruder, Avima M.; Sesso, Howard D.; Severi, Gianluca; Stampfer, Meir; Stevens, Victoria L.; Visvanathan, Kala; Wang, Sophia S.; White, Emily; Zeleniuch-Jacquotte, Anne; Hoover, Robert; Fraumeni, Joseph F.; Chatterjee, Nilanjan; Hartge, Patricia; Chanock, Stephen J.

2016-01-01

We confirmed strong association of rs78378222:A>C (per allele odds ratio [OR] = 3.14; P = 6.48 × 10−11), a germline rare single-nucleotide polymorphism (SNP) in TP53, via imputation of a genome-wide association study of glioma (1,856 cases and 4,955 controls). We subsequently performed integrative analyses on the Cancer Genome Atlas (TCGA) data for GBM (glioblastoma multiforme) and LUAD (lung adenocarcinoma). Based on SNP data, we imputed genotypes for rs78378222 and selected individuals carrying rare risk allele (C). Using RNA sequencing data, we observed aberrant transcripts with ~3 kb longer than normal for those individuals. Using exome sequencing data, we further showed that loss of haplotype carrying common protective allele (A) occurred somatically in GBM but not in LUAD. Our bioinformatic analysis suggests rare risk allele (C) disrupts mRNA termination, and an allelic loss of a genomic region harboring common protective allele (A) occurs during tumor initiation or progression for glioma. PMID:25907361

Studies of the Association of Arg72Pro of Tumor Suppressor Protein p53 with Type 2 Diabetes in a Combined Analysis of 55,521 Europeans

DEFF Research Database (Denmark)

Burgdorf, Kristoffer Sølvsten; Grarup, Niels; Justesen, Johanne Marie

2011-01-01

2 diabetes in the Danish samples. However, for all nine variants the estimate of increase in type 2 diabetes risk was observed for the same allele as previously reported. In a meta-analysis of published and online data including 55,521 Europeans the G-allele of rs1042522 in TP53 showed significant...... replicated associations in meta-analyses. Furthermore, we evaluated the impact on diabetes-related intermediate traits in a population-based sample of middle-aged Danes. Methods: We genotyped nine lead variants in the seven genes in 4,973 glucose-tolerant and 3,612 type 2 diabetes Danish individuals. In meta...... association with type 2 diabetes (OR = 1.06 95% CI 1.02–1.11, p = 0.0032). No substantial associations with diabetes-related intermediary phenotypes were found. Conclusion: The G-allele of TP53 rs1042522 is associated with an increased prevalence of type 2 diabetes in a combined analysis of 55,521 Europeans....

Catalytic oxidation of methanol on Pt/X (X = CaTP, NaTP electrodes in sulfuric acid solution

Directory of Open Access Journals (Sweden)

Said Benmokhtar

2013-10-01

Full Text Available In this paper, we report the synthesis and characterization of electrodes based on NASICON type phosphates. The study of the electrochemical oxidation of methanol at ambient temperature on electrodes based on NASICON type Ca0,5Ti2(PO43 (CaTP and Na5Ti(PO43 (NaTP compared to that of the platinum electrode model has been conducted by cyclic voltammetry in acidic medium. The results showed a significant increase of current density on the electro oxidation of methanol on the material developed based NASICON structure CaTP, cons deactivation of the electro oxidation is observed the closed structure type NaTP.

Protein 53 expression in a mixed Labrador subcutaneous lymphoma

Directory of Open Access Journals (Sweden)

Annahita Rezaie

2012-06-01

Full Text Available An 11 year – old mixed female Labrador was presented with two masses in trunk and neck. The tumoral masses were excised and sent for histopathological and immunohistochemical analyses. Histopathological examination of masses revealed diffuse infiltration of small sized lymphoid cells in subcutaneous tissue which were intense around the blood vessels. More than 10% lymphoid cells were CD3 positive in the immunohistochemical staining and most of them were accumulated around vessels. Protein 53 (p53 expression was detected by brown nuclei in immunohistochemical staining. Subcutaneous lymphoma was diagnosed according to histopathological results. After 6 months the case was referred with multicentric lymphoma and based on the owner request euthanasia was performed. These findings emphasize on poor prognosis for tumors with p53 mutation.

Generation of a selectively cytotoxic fusion protein against p53 mutated cancers

International Nuclear Information System (INIS)

Kousparou, Christina A; Yiacoumi, Efthymia; Deonarain, Mahendra P; Epenetos, Agamemnon A

2012-01-01

A significant number of cancers are caused by defects in p21 causing functional defects in p21 or p53 tumour-suppressor proteins. This has led to many therapeutic approaches including restoration by gene therapy with wild-type p53 or p21 using viral or liposomal vectors, which have toxicity or side-effect limitations. We set out to develop a safer, novel fusion protein which has the ability to reconstitute cancer cell lines with active p21 by protein transduction. The fusion protein was produced from the cell-translocating peptide Antennapedia (Antp) and wild-type, full-length p21 (Antp-p21). This was expressed and refolded from E. coli and tested on a variety of cell lines and tumours (in a BALB/c nude xenograft model) with differing p21 or p53 status. Antp-p21 penetrated and killed cancer cells that do not express wild type p53 or p21. This included cells that were matched to cogenic parental cell lines. Antp-p21 killed cancer cells selectively that were malignant as a result of mutations or nuclear exclusion of the p53 and p21 genes and over-expression of MDM2. Non-specific toxicity was excluded by showing that Antp-p21 penetrated but did not kill p53- or p21- wild-type cells. Antp-p21 was not immunogenic in normal New Zealand White rabbits. Recombinant Antp peptide alone was not cytotoxic, showing that killing was due to the transduction of the p21 component of Antp-p21. Antp-p21 was shown to penetrate cancer cells engrafted in vivo and resulted in tumour eradication when administered with conventionally-used chemotherapeutic agents, which alone were unable to produce such an effect. Antp-p21 may represent a new and promising targeted therapy for patients with p53-associated cancers supporting the concept that rational design of therapies directed against specific cancer mutations will play a part in the future of medical oncology

Generation of a selectively cytotoxic fusion protein against p53 mutated cancers

Directory of Open Access Journals (Sweden)

Kousparou Christina A

2012-08-01

Full Text Available Abstract Background A significant number of cancers are caused by defects in p21 causing functional defects in p21 or p53 tumour-suppressor proteins. This has led to many therapeutic approaches including restoration by gene therapy with wild-type p53 or p21 using viral or liposomal vectors, which have toxicity or side-effect limitations. We set out to develop a safer, novel fusion protein which has the ability to reconstitute cancer cell lines with active p21 by protein transduction. Methods The fusion protein was produced from the cell-translocating peptide Antennapedia (Antp and wild-type, full-length p21 (Antp-p21. This was expressed and refolded from E. coli and tested on a variety of cell lines and tumours (in a BALB/c nude xenograft model with differing p21 or p53 status. Results Antp-p21 penetrated and killed cancer cells that do not express wild type p53 or p21. This included cells that were matched to cogenic parental cell lines. Antp-p21 killed cancer cells selectively that were malignant as a result of mutations or nuclear exclusion of the p53 and p21 genes and over-expression of MDM2. Non-specific toxicity was excluded by showing that Antp-p21 penetrated but did not kill p53- or p21- wild-type cells. Antp-p21 was not immunogenic in normal New Zealand White rabbits. Recombinant Antp peptide alone was not cytotoxic, showing that killing was due to the transduction of the p21 component of Antp-p21. Antp-p21 was shown to penetrate cancer cells engrafted in vivo and resulted in tumour eradication when administered with conventionally-used chemotherapeutic agents, which alone were unable to produce such an effect. Conclusions Antp-p21 may represent a new and promising targeted therapy for patients with p53-associated cancers supporting the concept that rational design of therapies directed against specific cancer mutations will play a part in the future of medical oncology.

Overexpression of p53 activated by small activating RNA suppresses the growth of human prostate cancer cells

Directory of Open Access Journals (Sweden)

Ge Q

2016-01-01

Full Text Available Qiangqiang Ge,1,* Chenghe Wang,2,* Yajun Ruan,1,* Zhong Chen,1 Jihong Liu,1 Zhangqun Ye1 1Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 2Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Previous research has reported that a particular double-stranded RNA, named dsP53-285, has the capacity to induce expression of the tumor suppressor gene TP53 in chimpanzee cells by targeting its promoter. Usually, it is the wild-type p53 protein, rather than mutants, which exhibits potent cancer-inhibiting effects. In addition, nonhuman primates, such as chimpanzees, share almost identical genome sequences with humans. This prompted us to speculate whether dsP53-285 can trigger wild-type p53 protein expression in human prostate cancer (PCa cells and consequently suppress cell growth. The human PCa cell lines LNCaP and DU145 were transfected with dsP53-285 for 72 hours. Compared with the dsControl and mock transfection groups, expression of both p53 messenger RNA and p53 protein was significantly enhanced after dsP53-285 transfection, and this enhancement was followed by upregulation of p21, which indirectly indicated that dsP53-285 induced wild-type p53 expression. Moreover, overexpression of wild-type p53 mediated by dsP53-285 downregulated the expression of Cyclin D1 and cyclin-dependent kinase 4/6, thereby inducing PCa cell cycle arrest in G0/G1 phase and then inhibiting cell proliferation and clonogenicity. More importantly, dsP53-285 suppressed PCa cells mainly by modulating wild-type p53 expression. In conclusion, our study provides evidence that dsP53-285 can significantly stimulate wild-type p53 expression in the human PCa cell lines LNCaP and DU145 and can exert potent antitumor effects. Keywords: p53, small activating RNA, prostate

A Post-Truncation Parameterization of Truncated Normal Technical Inefficiency

OpenAIRE

Christine Amsler; Peter Schmidt; Wen-Jen Tsay

2013-01-01

In this paper we consider a stochastic frontier model in which the distribution of technical inefficiency is truncated normal. In standard notation, technical inefficiency u is distributed as N^+ (μ,σ^2). This distribution is affected by some environmental variables z that may or may not affect the level of the frontier but that do affect the shortfall of output from the frontier. We will distinguish the pre-truncation mean (μ) and variance (σ^2) from the post-truncation mean μ_*=E(u) and var...

Actual Proliferating Index and p53 protein expression as prognostic marker in odontogenic cysts.

Science.gov (United States)

Gadbail, A R; Chaudhary, M; Patil, S; Gawande, M

2009-10-01

The purpose of this study was to evaluate the biological aggressiveness of odontogenic keratocyst/keratocystic odontogenic tumour (KCOT), radicular cyst (RC) and dentigerous cyst (DC) by observing the actual proliferative activity of epithelium, and p53 protein expression. The actual proliferative activity was measured by Ki-67 Labelling Index and argyrophilic nucleolar organizing regions (AgNOR) count per nucleus. The p53 protein expression was also evaluated. Ki-67 positive cells were observed higher in suprabasal cell layers of KCOT with uniform distribution, a few of them were predominantly observed in basal cell layer in RC and DC. The AgNOR count was significantly higher in suprabasal cell layers of KCOT. The actual proliferative activity was noted to be higher in suprabasal cell layers of KCOT. The p53 immunolabelling was dense and scattered in basal and suprabasal cell layers in KCOT. The weakly stained p53 positive cells were observed diffusely distributed in KCOT, whereas they were mainly seen in basal cell layer of RC and DC. The quantitative and qualitative differences of the proliferative activity and the p53 protein expression in sporadic KCOT may be associated with intrinsic growth potential that could play a role in its development and explain locally aggressive biological behaviour. AgNOR count and p53 protein detection in odontogenic lesions can be of great consequence to predict the biological behaviour and prognosis.

Imunolocalização das proteínas dos genes supressores de tumores TP53 e p16CDKN2 no front invasivo do carcinoma epidermóide de cavidade bucal Immunolocalization of TP53 and p16CDKN2 tumour suppressor genes proteins in invasive front of oral epidermoid carcinoma

Directory of Open Access Journals (Sweden)

Alfredo Maurício Batista De-Paula

2006-08-01

vias moleculares independentes.BACKGROUND: Oral carcinogenesis is a multistep process in which genetic events lead to the disruption of the normal regulatory pathways that control basic cellular functions. Epidermoid carcinoma of oral cavity (ECOC appears as a consequence of multiple molecular events induced by the effects of several carcinogens influenced by environmental factors against a background of genetic resistance or susceptibility. Consequent genetic damage affects many chromosomes and genes, and the accumulation of these changes seems to lead to ECOC. OBJECTIVES: The aim of the present study was to assess the clinical and morphological value of p53 and p16 immunolocalization at the invasive tumor front in a representative series of 35 routinely processed ECOC. MATERIAL AND METHODS: Samples of ECOC were investigated in this study. TNM system was employed for clinical staging and the invasive front grading system was employed for morphological grading of the lesions. Immunohistochemical technique in paraffin-embedded and formalin-fixed tissues was utilized to immunolocalization of p53 and p16 proteins. Counts were performed and submitted to specific statistical treatments. RESULTS: p53 and p16 immunolocalizations were detected in 63% and 66%, respectively, of 35 carcinomas studied. No correlation was found between p53 and p16 expressions and clinico-morphological parameters statistically analyzed. No correlation was found between the relationship p53/p16 expressions. CONCLUSION: p53 and p16 immunolocalization did not influence the clinico-morphological parameters analyzed in this study and apparently do not represent a molecular basis for the biologic significance of the invasive tumor front. Lack of a strong correlation between p53 and p16 immunolocalization suggests that both could participate in biological activities in the cell cycle control by independent molecular pathways.

Equivalence of truncated count mixture distributions and mixtures of truncated count distributions.

Science.gov (United States)

Böhning, Dankmar; Kuhnert, Ronny

2006-12-01

This article is about modeling count data with zero truncation. A parametric count density family is considered. The truncated mixture of densities from this family is different from the mixture of truncated densities from the same family. Whereas the former model is more natural to formulate and to interpret, the latter model is theoretically easier to treat. It is shown that for any mixing distribution leading to a truncated mixture, a (usually different) mixing distribution can be found so that the associated mixture of truncated densities equals the truncated mixture, and vice versa. This implies that the likelihood surfaces for both situations agree, and in this sense both models are equivalent. Zero-truncated count data models are used frequently in the capture-recapture setting to estimate population size, and it can be shown that the two Horvitz-Thompson estimators, associated with the two models, agree. In particular, it is possible to achieve strong results for mixtures of truncated Poisson densities, including reliable, global construction of the unique NPMLE (nonparametric maximum likelihood estimator) of the mixing distribution, implying a unique estimator for the population size. The benefit of these results lies in the fact that it is valid to work with the mixture of truncated count densities, which is less appealing for the practitioner but theoretically easier. Mixtures of truncated count densities form a convex linear model, for which a developed theory exists, including global maximum likelihood theory as well as algorithmic approaches. Once the problem has been solved in this class, it might readily be transformed back to the original problem by means of an explicitly given mapping. Applications of these ideas are given, particularly in the case of the truncated Poisson family.

Total Pancreatectomy (TP) and Islet Autotransplantation (IAT) for Chronic Pancreatitis (CP)

Science.gov (United States)

Sutherland, David E.R.; Radosevich, David M.; Bellin, Melena D.; Hering, Bernard J.; Beilman, Gregory J.; Dunn, Ty B.; Chinnakotla, Srinath; Vickers, Selwyn M.; Bland, Barbara; Balamurugan, A.N.; Freeman, Martin L.; Pruett, Timothy L.

2013-01-01

Background Total-pancreatectomy (TP) with intraportal-islet-auto-transplantation (IAT) can relieve pain and preserve beta-cell-mass in patients with chronic-pancreatitis (CP) when other-therapies fail. Reported is a >30-year-single-center-series. Study Design 409 patients (53 children, 5–18 yrs) with CP underwent TP-IAT from Feb/1977–Sept/2011; (etiology idiopathic-41%; SOD/biliary-9%; genetic-14%; divisum-17%; alcohol-7%; other-12%); mean age-35.3 yrs,); 74% female; prior-surgeries 21%--Puestow procedure 9%, Whipple 6%, distal pancreatectomy 7%; other 2%). Islet-function was classified as insulin-independent for those on no insulin; partial if known C-peptide positive or euglycemic on once-daily-insulin; and insulin-dependent if on standard basal–bolus diabetic regimen. An SF-36-survey for Quality-of-Life (QOL)) was completed before and in serial follow-up by patients done since 2007 with an integrated-survey that added in 2008. Results Actuarial-patient-survival post-TP-IAT was 96% in adults and 98% in children (1-year) and; 89% and 98% (5-years). Complications requiring relaparotomy occurred in 15.9%, bleeding (9.5%) being most common. IAT-function is achieved in 90% (C-peptide >0.6 ng/ml). At 3 years, 30% were insulin-independent (25% in adults, 55% in children) and 33% had partial-function. Mean HbA1C was 5000/kg (24%)] correlated with degree of function with insulin-independent rates at 3 yrs of 12, 22 and 72%, partial function 33, 62 and 24%. All patients had pain before TP-IAT and nearly all were on daily-narcotics. After TP-IAT, 85% had pain-improvement. By two years 59% had ceased-narcotics. All children were on narcotics before, 39% at follow-up; pain improved in 94%; 67% became pain-free. In the SF-36 survey, there was significant improvement from baseline in all dimensions including the Physical and Mental Component Summaries (P2/3 of patients with insulin-independence occurring in one-quarter of adults and half the children. PMID:22397977

Immunohistochemical Expression of P53 Protein in Cutaneous Basal Cell Carcinoma: A Clinicopathological Study of 66 Cases

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Vladim and iacute;r Barto and scaron;

2016-12-01

Full Text Available Objective: Nuclear expression of p53 protein is associated with a biological behavior in a variety of human malignancies. In cutaneous basal cell carcinoma (BCC, however, many studies have provided conflicting results in this regard. We aimed to determine whether there is relationship between p53 expression and different histologic subtypes of BCC, and whether it may indicate tumor aggressiveness. Materials and Methods: Biopsy samples from 66 cutaneous BCCs from 57 patients were collected. P53 expression was demonstrated by immunohistochemical staining using the anti-p53 antibody. Among them, 52 cases were also evaluated for Ki-67 antigen. Results: Immunoreactivity of p53 protein varied in the range of 0 to 100% of total tumor tissue (mean value 46.0%. The expression exceeding 5% of cancer tissue (positive staining was found in 54 BCCs (81.8%. Within this group, there were 25 cases (37.9% with low and 29 cases (43.9% with high expression. In superficial, superficial-nodular, nodular, nodular-infiltrative and infiltrative BCCs, p53 protein positivity was found in 100% (8/8, 80% (8/10, 70.4% (19/27, 88.2% (15/17 and 100% (4/4, respectively. We did not reveal a significant correlation between the extent of p53 protein expression and BCC subtypes except for nodular BCC, in which a number of negative cases (8/27, 29.6% were just above the threshold of statistical significance (P = 0.04. After merging cancers into non-aggressive and aggressive growth phenotype, no association with expression of p53 protein was found. There was no relationship between p53 protein expression and topographical sites after they have been gathered into sun-exposed and sun-protected locations. We did not observe any association between expression of p53 protein and Ki-67 antigen. Conclusion: In cutaneous BCC, the expression of p53 protein does not seem to reflect a biological behavior and tumor aggressiveness. Therefore, in a routine dermatopathological practice

How Truncating Are 'Truncating Languages'? Evidence from Russian and German.

Science.gov (United States)

Rathcke, Tamara V

Russian and German have pr eviously been described as 'truncating', or cutting off target frequencies of the phrase-final pitch trajectories when the time available for voicing is compromised. However, supporting evidence is rare and limited to only a few pitch categories. This paper reports a production study conducted to document pitch adjustments to linguistic materials, in which the amount of voicing available for the realization of a pitch pattern varies from relatively long to extremely short. Productions of nuclear H+L*, H* and L*+H pitch accents followed by a low boundary tone were investigated in the two languages. The results of the study show that speakers of both 'truncating languages' do not utilize truncation exclusively when accommodating to different segmental environments. On the contrary, they employ several strategies - among them is truncation but also compression and temporal re-alignment - to produce the target pitch categories under increasing time pressure. Given that speakers can systematically apply all three adjustment strategies to produce some pitch patterns (H* L% in German and Russian) while not using truncation in others (H+L* L% particularly in Russian), we question the effectiveness of the typological classification of these two languages as 'truncating'. Moreover, the phonetic detail of truncation varies considerably, both across and within the two languages, indicating that truncation cannot be easily modeled as a unified phenomenon. The results further suggest that the phrase-final pitch adjustments are sensitive to the phonological composition of the tonal string and the status of a particular tonal event (associated vs. boundary tone), and do not apply to falling vs. rising pitch contours across the board, as previously put forward for German. Implications for the intonational phonology and prosodic typology are addressed in the discussion. © 2017 S. Karger AG, Basel.

A resolvase-like protein is requered for the site-specific integration of the temperate lactococcal bacteriophage TP901-1

DEFF Research Database (Denmark)

Christiansen, Bettina; Brøndsted, Lone; Vogensen, Finn K.

1996-01-01

upstream of attP. The N-terminal 150 to 1180 amino acids of Orf1 showed 38 to 44% similarity to the resolvase group of site-specific integrases, while no similarity to know proteins was found in the C-terminal end. Bacteriophage 'TP901-1 therefore contains a unique integration system that does not resemble...... the Int class of site-specific integrases usually found in temperate bacteriophages. The constructed integration vector, pBC170, integrates into the chromosomal attachment site very efficiently and forms stable transformants with a frequency corresponding to 20% of the transformation efficiency....

Protein: MPA1 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPA1 TLR signaling molecules Rsad2 Vig1 Radical S-adenosyl methionine domain-containing pr...otein 2 Viperin, Virus inhibitory protein, endoplasmic reticulum-associated, interferon-inducible 10090 Mus musculus 58185 Q8CBB9 21435586 ...

Chemical Variations on the p53 Reactivation Theme

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Carlos J. A. Ribeiro

2016-05-01

Full Text Available Among the tumor suppressor genes, p53 is one of the most studied. It is widely regarded as the “guardian of the genome”, playing a major role in carcinogenesis. In fact, direct inactivation of the TP53 gene occurs in more than 50% of malignancies, and in tumors that retain wild-type p53 status, its function is usually inactivated by overexpression of negative regulators (e.g., MDM2 and MDMX. Hence, restoring p53 function in cancer cells represents a valuable anticancer approach. In this review, we will present an updated overview of the most relevant small molecules developed to restore p53 function in cancer cells through inhibition of the p53-MDMs interaction, or direct targeting of wild-type p53 or mutated p53. In addition, optimization approaches used for the development of small molecules that have entered clinical trials will be presented.

Protein: MPB2 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPB2 Ubiquitin ligases STUB1 CHIP STUB1 E3 ubiquitin-protein ligase CHIP Antigen NY...-CO-7, CLL-associated antigen KW-8, Carboxy terminus of Hsp70-interacting protein, STIP1 homology and U box-containing pr

Overexpression of p53, MDM2 proteins in some atr radiation-induced skin ulcers

International Nuclear Information System (INIS)

Gu Qingyang; Gao Yabing; Wang Dewen; Cui Yufang; Zhao Po; Yang Zhixiang; Zhou Jie

2000-01-01

An animal model of radiation-induced skin ulcer was set up with 140 rats, which were locally irradiated with 35-55 Gy γ-rays. The pathological changes were observed for 1 year. Immunohistochemical studies were performed in 72 rat radiation skin ulcer specimens using anti-p53 and anti-MDM2 proteins polyclonal antibodies. The results showed that the positive rate for overexpression of p53 protein was 9.7%, and for that of MDM2 was 19.4%. The overexpression of p53 was mainly seen in the nuclei of activated squamous epithelial cells, and in fibroblasts, endotheliocytes in deeper part of the skin ulcers. The overexpression of MDM2 had the same localizations. It is suggested that the changes of p53 and MDM2, genes and proteins, may be related to the cancer transformation and poor healing of radiation-induced skin ulcers

Radiation-induced p53 protein response in the A549 cell line is culture growth-phase dependent

Energy Technology Data Exchange (ETDEWEB)

Johnson, N.F.; Gurule, D.M.; Carpenter, T.R.

1995-12-01

One role of the p53 tumor suppressor protein has been recently revealed. Kastan, M.B. reported that p53 protein accumulates in cells exposed to ionizing radiation. The accumulation of p53 protein is in response to DNA damage, most importantly double-strand breaks, that results from exposure to ionizing radiation. The rise in cellular p53 levels is necessary for an arrest in the G{sub 1} phase of the cell cycle to provide additional time for DNA repair. The p53 response has also been demonstrated to enhance PCNA-dependent repair. p53 is thus an important regulator of the cellular response to DNA-damaging radiation. From this data, it can be concluded that the magnitude of the p53 response is not dependent on the phase of culture growth.

Protein: MPB4 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPB4 Sema3A signaling molecules DPYSL2 CRMP2, ULIP2 DPYSL2 Dihydropyrimidinase-related pr...otein 2 Collapsin response mediator protein 2, N2A3, Unc-33-like phosphoprotein 2 9606 Homo sapiens Q16555 1808 2VM8, 2GSE 1808 Q16555 ...

Protein: FBA6 [TP Atlas

Lifescience Database Archive (English)

Full Text Available FBA6 vesicular transport RAB11FIP3 ARFO1, KIAA0665 RAB11FIP3 Rab11 family-interacting pr...otein 3 Arfophilin-1, EF hands-containing Rab-interacting protein, MU-MB-17.148 9606 Homo sapiens O75154 9727 2HV8 2D7C 9727 21790911 ...

Modulation of Wound Healing and Scar Formation by MG53 Protein-mediated Cell Membrane Repair*

Science.gov (United States)

Li, Haichang; Duann, Pu; Lin, Pei-Hui; Zhao, Li; Fan, Zhaobo; Tan, Tao; Zhou, Xinyu; Sun, Mingzhai; Fu, Minghuan; Orange, Matthew; Sermersheim, Matthew; Ma, Hanley; He, Duofen; Steinberg, Steven M.; Higgins, Robert; Zhu, Hua; John, Elizabeth; Zeng, Chunyu; Guan, Jianjun; Ma, Jianjie

2015-01-01

Cell membrane repair is an important aspect of physiology, and disruption of this process can result in pathophysiology in a number of different tissues, including wound healing, chronic ulcer and scarring. We have previously identified a novel tripartite motif family protein, MG53, as an essential component of the cell membrane repair machinery. Here we report the functional role of MG53 in the modulation of wound healing and scarring. Although MG53 is absent from keratinocytes and fibroblasts, remarkable defects in skin architecture and collagen overproduction are observed in mg53−/− mice, and these animals display delayed wound healing and abnormal scarring. Recombinant human MG53 (rhMG53) protein, encapsulated in a hydrogel formulation, facilitates wound healing and prevents scarring in rodent models of dermal injuries. An in vitro study shows that rhMG53 protects against acute injury to keratinocytes and facilitates the migration of fibroblasts in response to scratch wounding. During fibrotic remodeling, rhMG53 interferes with TGF-β-dependent activation of myofibroblast differentiation. The resulting down-regulation of α smooth muscle actin and extracellular matrix proteins contributes to reduced scarring. Overall, these studies establish a trifunctional role for MG53 as a facilitator of rapid injury repair, a mediator of cell migration, and a modulator of myofibroblast differentiation during wound healing. Targeting the functional interaction between MG53 and TGF-β signaling may present a potentially effective means for promoting scarless wound healing. PMID:26306047

Protein: MPB2 [TP Atlas

Lifescience Database Archive (English)

Full Text Available MPB2 Ubiquitin ligases SMURF1 KIAA1625 SMURF1 E3 ubiquitin-protein ligase SMURF1 SM...AD ubiquitination regulatory factor 1, SMAD-specific E3 ubiquitin-protein ligase 1 9606 Homo sapiens Q9HCE7 57154 2LB1, 2LAZ, 2LB0, 3PYC 57154 Q9HCE7 ...

Studies of the viral binding proteins of shrimp BP53, a receptor of white spot syndrome virus.

Science.gov (United States)

Li, Chen; Gao, Xiao-Xiao; Huang, Jie; Liang, Yan

2016-02-01

The specific binding between viral attachment proteins (VAPs) of a virus and its cellular receptors on host cells mediates virus entry into host cells, which triggers subsequent viral infections. Previous studies indicate that F1 ATP synthase β subunit (named BP53), is found on the surface of shrimp cells and involved in white spot syndrome virus (WSSV) infection by functioning as a potential viral receptor. Herein, in a far-western blotting assay, three WSSV proteins with molecular weights of 28 kDa, 37 kDa, and >50 kDa were found to interact with BP53. The 28 kDa and 37 kDa proteins were identified as the envelope protein VP28 and VP37 of WSSV respectively, which could be recognized by the polyclonal antibodies. Enzyme-linked immunosorbent binding assays revealed that VP37 contributed to almost 80% of the binding capability for BP53 compared with the same amount of total WSSV protein. The relationship between BP53 and its complementary interacting protein, VP37, was visualized using a co-localization assay. Bound VP37 on the cell surface co-localized with BP53 and shared a similar subcellular location on the outer surface of shrimp cells. Pearson's correlation coefficients reached to 0.67 ± 0.05 and the Mander's overlap coefficients reached 0.70 ± 0.05, which indicated a strong relationship between the localization of BP53 and bound rVP37. This provides evidence for an interaction between BP53 and VP37 obtained at the molecular and cellular levels, supporting the hypothesis that BP53 serves as a receptor for WSSV by binding to VP37. The identification of the viral binding proteins of shrimp BP53 is helpful for better understanding the pathogenic mechanisms of WSSV to infect shrimp at the cellular level. Copyright © 2016 Elsevier Inc. All rights reserved.

Molecular dynamics simulation of S100B protein to explore ligand blockage of the interaction with p53 protein

Science.gov (United States)

Zhou, Zhigang; Li, Yumin

2009-10-01

As a tumor suppressor, p53 plays an important role in cancer suppression. The biological function of p53 as a tumor suppressor is disabled when it binds to S100B. Developing the ligands to block the S100B-p53 interaction has been proposed as one of the most important approaches to the development of anti-cancer agents. We screened a small compound library against the binding interface of S100B and p53 to identify potential compounds to interfere with the interaction. The ligand-binding effect on the S100B-p53 interaction was explored by molecular dynamics at the atomic level. The results show that the ligand bound between S100B and p53 propels the two proteins apart by about 2 Å compared to the unligated S100B-p53 complex. The binding affinity of S100B and p53 decreases by 8.5-14.6 kcal/mol after a ligand binds to the interface from the original unligated state of the S100B-p53 complex. Ligand-binding interferes with the interaction of S100B and p53. Such interference could impact the association of S100B and p53, which would free more p53 protein from the pairing with S100B and restore the biological function of p53 as a tumor suppressor. The analysis of the binding mode and ligand structural features would facilitate our effort to identify and design ligands to block S100B-p53 interaction effectively. The results from the work suggest that developing ligands targeting the interface of S100B and p53 could be a promising approach to recover the normal function of p53 as a tumor suppressor.

TGEV nucleocapsid protein induces cell cycle arrest and apoptosis through activation of p53 signaling

International Nuclear Information System (INIS)

Ding, Li; Huang, Yong; Du, Qian; Dong, Feng; Zhao, Xiaomin; Zhang, Wenlong; Xu, Xingang; Tong, Dewen

2014-01-01

Highlights: • TGEV N protein reduces cell viability by inducing cell cycle arrest and apoptosis. • TGEV N protein induces cell cycle arrest and apoptosis by regulating p53 signaling. • TGEV N protein plays important roles in TGEV-induced cell cycle arrest and apoptosis. - Abstract: Our previous studies showed that TGEV infection could induce cell cycle arrest and apoptosis via activation of p53 signaling in cultured host cells. However, it is unclear which viral gene causes these effects. In this study, we investigated the effects of TGEV nucleocapsid (N) protein on PK-15 cells. We found that TGEV N protein suppressed cell proliferation by causing cell cycle arrest at the S and G2/M phases and apoptosis. Characterization of various cellular proteins that are involved in regulating cell cycle progression demonstrated that the expression of N gene resulted in an accumulation of p53 and p21, which suppressed cyclin B1, cdc2 and cdk2 expression. Moreover, the expression of TGEV N gene promoted translocation of Bax to mitochondria, which in turn caused the release of cytochrome c, followed by activation of caspase-3, resulting in cell apoptosis in the transfected PK-15 cells following cell cycle arrest. Further studies showed that p53 inhibitor attenuated TGEV N protein induced cell cycle arrest at S and G2/M phases and apoptosis through reversing the expression changes of cdc2, cdk2 and cyclin B1 and the translocation changes of Bax and cytochrome c induced by TGEV N protein. Taken together, these results demonstrated that TGEV N protein might play an important role in TGEV infection-induced p53 activation and cell cycle arrest at the S and G2/M phases and apoptosis occurrence

R Programs for Truncated Distributions

Directory of Open Access Journals (Sweden)

Saralees Nadarajah

2006-08-01

Full Text Available Truncated distributions arise naturally in many practical situations. In this note, we provide programs for computing six quantities of interest (probability density function, mean, variance, cumulative distribution function, quantile function and random numbers for any truncated distribution: whether it is left truncated, right truncated or doubly truncated. The programs are written in R: a freely downloadable statistical software.

Proposed megakaryocytic regulon of p53: the genes engaged to control cell cycle and apoptosis during megakaryocytic differentiation

Science.gov (United States)

Apostolidis, Pani A.; Lindsey, Stephan; Miller, William M.

2012-01-01

During endomitosis, megakaryocytes undergo several rounds of DNA synthesis without division leading to polyploidization. In primary megakaryocytes and in the megakaryocytic cell line CHRF, loss or knock-down of p53 enhances cell cycling and inhibits apoptosis, leading to increased polyploidization. To support the hypothesis that p53 suppresses megakaryocytic polyploidization, we show that stable expression of wild-type p53 in K562 cells (a p53-null cell line) attenuates the cells' ability to undergo polyploidization during megakaryocytic differentiation due to diminished DNA synthesis and greater apoptosis. This suggested that p53's effects during megakaryopoiesis are mediated through cell cycle- and apoptosis-related target genes, possibly by arresting DNA synthesis and promoting apoptosis. To identify candidate genes through which p53 mediates these effects, gene expression was compared between p53 knock-down (p53-KD) and control CHRF cells induced to undergo terminal megakaryocytic differentiation using microarray analysis. Among substantially downregulated p53 targets in p53-KD megakaryocytes were cell cycle regulators CDKN1A (p21) and PLK2, proapoptotic FAS, TNFRSF10B, CASP8, NOTCH1, TP53INP1, TP53I3, DRAM1, ZMAT3 and PHLDA3, DNA-damage-related RRM2B and SESN1, and actin component ACTA2, while antiapoptotic CKS1B, BCL2, GTSE1, and p53 family member TP63 were upregulated in p53-KD cells. Additionally, a number of cell cycle-related, proapoptotic, and cytoskeleton-related genes with known functions in megakaryocytes but not known to carry p53-responsive elements were differentially expressed between p53-KD and control CHRF cells. Our data support a model whereby p53 expression during megakaryopoiesis serves to control polyploidization and the transition from endomitosis to apoptosis by impeding cell cycling and promoting apoptosis. Furthermore, we identify a putative p53 regulon that is proposed to orchestrate these effects. PMID:22548738

Distinct Rayleigh scattering from hot spot mutant p53 proteins reveals cancer cells.

Science.gov (United States)

Jun, Ho Joon; Nguyen, Anh H; Kim, Yeul Hong; Park, Kyong Hwa; Kim, Doyoun; Kim, Kyeong Kyu; Sim, Sang Jun

2014-07-23

The scattering of light redirects and resonances when an electromagnetic wave interacts with electrons orbits in the hot spot core protein and oscillated electron of the gold nanoparticles (AuNP). This report demonstrates convincingly that resonant Rayleigh scattering generated from hot spot mutant p53 proteins is correspondence to cancer cells. Hot spot mutants have unique local electron density changes that affect specificity of DNA binding affinity compared with wild types. Rayleigh scattering changes introduced by hot-spot mutations were monitored by localized surface plasmon resonance (LSPR) shift changes. The LSPR λmax shift for hot-spot mutants ranged from 1.7 to 4.2 nm for mouse samples and from 0.64 nm to 2.66 nm for human samples, compared to 9.6 nm and 15 nm for wild type and mouse and human proteins, respectively with a detection sensitivity of p53 concentration at 17.9 nM. It is interesting that hot-spot mutants, which affect only interaction with DNA, launches affinitive changes as considerable as wild types. These changes propose that hot-spot mutants p53 proteins can be easily detected by local electron density alterations that disturbs the specificity of DNA binding of p53 core domain on the surface of the DNA probed-nanoplasmonic sensor. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Charge neutralization as the major factor for the assembly of nucleocapsid-like particles from C-terminal truncated hepatitis C virus core protein

OpenAIRE

Theo Luiz Ferraz de Souza; Sheila Maria Barbosa de Lima; Vanessa L. de Azevedo Braga; David S. Peabody; Davis Fernandes Ferreira; M. Lucia Bianconi; Andre Marco de Oliveira Gomes; Jerson Lima Silva; Andréa Cheble de Oliveira

2016-01-01

Background Hepatitis C virus (HCV) core protein, in addition to its structural role to form the nucleocapsid assembly, plays a critical role in HCV pathogenesis by interfering in several cellular processes, including microRNA and mRNA homeostasis. The C-terminal truncated HCV core protein (C124) is intrinsically unstructured in solution and is able to interact with unspecific nucleic acids, in the micromolar range, and to assemble into nucleocapsid-like particles (NLPs) in vitro. The specific...

Novel variant in the TP63 gene associated to ankyloblepharon-ectodermal dysplasia-cleft lip/palate (AEC) syndrome.

Science.gov (United States)

Gonzalez, Francisco; Loidi, Lourdes; Abalo-Lojo, Jose M

2017-01-01

Ankyloblepharon-ectodermal dysplasia-cleft lip/palate (AEC) syndrome is a disorder resulting from anomalous embryonic development of ectodermal tissues. There is evidence that AEC syndrome is caused by mutations in the TP63 gene, which encodes the p63 protein. This is an important regulatory protein involved in epidermal proliferation and differentiation. Genome sequencing was performed in DNA from peripheral blood leukocytes of a newborn with AEC syndrome and her parents. Variants were searched in all coding exons and intron-exon boundaries of the TP63 gene. A heterozygous missense variant (NM_003722.4:c.1063G>C (p.Asp355His) was found in the newborn patient. No variants were found in either of the parents. We identified a previously unreported variant in TP63 gene which seems to be involved in the somatic malformations found in the AEC syndrome. The absence of this variant in both parents suggests that the variant appeared de novo.

The expanding regulatory universe of p53 in gastrointestinal cancer [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Andrew Fesler

2016-04-01

Full Text Available Tumor suppresser gene TP53 is one of the most frequently deleted or mutated genes in gastrointestinal cancers. As a transcription factor, p53 regulates a number of important protein coding genes to control cell cycle, cell death, DNA damage/repair, stemness, differentiation and other key cellular functions. In addition, p53 is also able to activate the expression of a number of small non-coding microRNAs (miRNAs through direct binding to the promoter region of these miRNAs.  Many miRNAs have been identified to be potential tumor suppressors by regulating key effecter target mRNAs. Our understanding of the regulatory network of p53 has recently expanded to include long non-coding RNAs (lncRNAs. Like miRNA, lncRNAs have been found to play important roles in cancer biology.  With our increased understanding of the important functions of these non-coding RNAs and their relationship with p53, we are gaining exciting new insights into the biology and function of cells in response to various growth environment changes. In this review we summarize the current understanding of the ever expanding involvement of non-coding RNAs in the p53 regulatory network and its implications for our understanding of gastrointestinal cancer.

Modulation of wound healing and scar formation by MG53 protein-mediated cell membrane repair.

Science.gov (United States)

Li, Haichang; Duann, Pu; Lin, Pei-Hui; Zhao, Li; Fan, Zhaobo; Tan, Tao; Zhou, Xinyu; Sun, Mingzhai; Fu, Minghuan; Orange, Matthew; Sermersheim, Matthew; Ma, Hanley; He, Duofen; Steinberg, Steven M; Higgins, Robert; Zhu, Hua; John, Elizabeth; Zeng, Chunyu; Guan, Jianjun; Ma, Jianjie

2015-10-02

Cell membrane repair is an important aspect of physiology, and disruption of this process can result in pathophysiology in a number of different tissues, including wound healing, chronic ulcer and scarring. We have previously identified a novel tripartite motif family protein, MG53, as an essential component of the cell membrane repair machinery. Here we report the functional role of MG53 in the modulation of wound healing and scarring. Although MG53 is absent from keratinocytes and fibroblasts, remarkable defects in skin architecture and collagen overproduction are observed in mg53(-/-) mice, and these animals display delayed wound healing and abnormal scarring. Recombinant human MG53 (rhMG53) protein, encapsulated in a hydrogel formulation, facilitates wound healing and prevents scarring in rodent models of dermal injuries. An in vitro study shows that rhMG53 protects against acute injury to keratinocytes and facilitates the migration of fibroblasts in response to scratch wounding. During fibrotic remodeling, rhMG53 interferes with TGF-β-dependent activation of myofibroblast differentiation. The resulting down-regulation of α smooth muscle actin and extracellular matrix proteins contributes to reduced scarring. Overall, these studies establish a trifunctional role for MG53 as a facilitator of rapid injury repair, a mediator of cell migration, and a modulator of myofibroblast differentiation during wound healing. Targeting the functional interaction between MG53 and TGF-β signaling may present a potentially effective means for promoting scarless wound healing. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Nongenotoxic p53 activation protects cells against S-phase-specific chemotherapy

DEFF Research Database (Denmark)

Kranz, Dominique; Dobbelstein, Matthias

2006-01-01

Mutations in the tumor suppressor gene TP53 represent the most frequent genetic difference between tumor cells and normal cells. Here, we have attempted to turn this difference into an advantage for normal cells during therapy. Using the Mdm2 antagonist nutlin-3, we first activated p53 in U2OS an...... a killer to a protector of cells, with the potential to reduce unwanted side effects of chemotherapy....

P53 Gene Mutation as Biomarker of Radiation Induced Cell Injury and Genomic Instability

International Nuclear Information System (INIS)

Mukh-Syaifudin

2006-01-01

Gene expression profiling and its mutation has become one of the most widely used approaches to identify genes and their functions in the context of identify and categorize genes to be used as radiation effect markers including cell and tissue sensitivities. Ionizing radiation produces genetic damage and changes in gene expression that may lead to cancer due to specific protein that controlling cell proliferation altered the function, its expression or both. P53 protein encoded by p53 gene plays an important role in protecting cell by inducing growth arrest and or cell suicide (apoptosis) after deoxyribonucleic acid (DNA) damage induced by mutagen such as ionizing radiation. The mutant and thereby dysfunctional of this gene was found in more than 50% of various human cancers, but it is as yet unclear how p53 mutations lead to neoplastic development. Wild-type p53 has been postulated to play a role in DNA repair, suggesting that expression of mutant forms of p53 might alter cellular resistance to the DNA damage caused by radiation. Moreover, p53 is thought to function as a cell cycle checkpoint after irradiation, also suggesting that mutant p53 might change the cellular proliferative response to radiation. P53 mutations affect the cellular response to DNA damage, either by increasing DNA repair processes or, possibly, by increasing cellular tolerance to DNA damage. The association of p53 mutations with increased radioresistance suggests that alterations in the p53 gene might lead to oncogenic transformation. Current attractive model of carcinogenesis also showed that p53 gene is the major target of radiation. The majority of p53 mutations found so far is single base pair changes ( point mutations), which result in amino acid substitutions or truncated forms of the p53 protein, and are widely distributed throughout the evolutionary conserved regions of the gene. Examination of p53 mutations in human cancer also shows an association between particular carcinogens and

Synthesis of total protein (TP) and myosin heavy chain (HC) isozymes in pressure overloaded rabbit hearts