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1.
Diagnostics (Basel) ; 14(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38337803

RESUMO

(1) Background: Somatic mutations may be connected to the exposome, potentially playing a role in breast cancer's development and clinical outcomes. There needs to be information regarding Latin American women specifically, as they are underrepresented in clinical trials and have limited access to somatic analysis in their countries. This study aims to systematically investigate somatic mutations in breast cancer patients from Latin America to gain a better understanding of tumor biology in the region. (2) Methods: We realize a systematic review of studies on breast cancer in 21 Latin American countries using various databases such as PubMed, Google Scholar, Web of Science, RedAlyc, Dianlet, and Biblioteca Virtual en Salud. Of 392 articles that fit the criteria, 10 studies have clinical data which can be used to create a database containing clinical and genetic information. We compared mutation frequencies across different breast cancer subtypes using statistical analyses and meta-analyses of proportions. Furthermore, we identified overexpressed biological processes and canonical pathways through functional enrichment analysis. (3) Results: 342 mutations were found in six Latin American countries, with the TP53 and PIK3CA genes being the most studied mutations. The most common PIK3CA mutation was H1047R. Functional analysis provided insights into tumor biology and potential therapies. (4) Conclusion: evaluating specific somatic mutations in the Latin American population is crucial for understanding tumor biology and determining appropriate treatment options. Combining targeted therapies may improve clinical outcomes in breast cancer. Moreover, implementing healthy lifestyle strategies in Latin America could enhance therapy effectiveness and clinical outcomes.

2.
Cancer Med ; 13(3): e6729, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38308422

RESUMO

BACKGROUND: Approximately 3/4 of ovarian cancers are diagnosed in advanced stages, with the high-grade epithelial ovarian carcinoma (EOC) accounting for 90% of the cases. EOC present high genomic instability and somatic loss-of-function variants in genes associated with homologous recombination mutational repair pathway (HR), such as BRCA1 and BRCA2, and in TP53. The identification of germline variants in HR genes in EOC is relevant for treatment of platinum resistant tumors and relapsed tumors with therapies based in synthetic lethality such as PARP inhibitors. Patients with somatic variants in HR genes may also benefit from these therapies. In this work was analyzed the frequency of somatic variants in BRCA1, BRCA2, and TP53 in an EOC cohort of Brazilian patients, estimating the proportion of variants in tumoral tissue and their association with progression-free survival and overall survival. METHODS: The study was conducted with paired blood/tumor samples from 56 patients. Germline and tumoral sequences of BRCA1, BRCA2, and TP53 were obtained by massive parallel sequencing. The HaplotypeCaller method was used for calling germline variants, and somatic variants were called with Mutect2. RESULTS: A total of 26 germline variants were found, and seven patients presented germline pathogenic or likely pathogenic variants in BRCA1 or BRCA2. The analysis of tumoral tissue identified 52 somatic variants in 41 patients, being 43 somatic variants affecting or likely affecting protein functionality. Survival analyses showed that tumor staging was associated with overall survival (OS), while the presence of somatic mutation in TP53 was not associated with OS or progression-free survival. CONCLUSION: Frequency of pathogenic or likely pathogenic germline variants in BRCA1 and BRCA2 (12.5%) was lower in comparison with other studies. TP53 was the most altered gene in tumors, with 62.5% presenting likely non-functional or non-functional somatic variants, while eight 14.2% presented likely non-functional or non-functional somatic variants in BRCA1 or BRCA2.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Carcinoma Epitelial do Ovário/genética , Brasil/epidemiologia , Neoplasias Ovarianas/genética , Reparo do DNA , Células Germinativas , Proteína Supressora de Tumor p53/genética , Proteína BRCA1/genética , Proteína BRCA2/genética
3.
Ecancermedicalscience ; 16: 1448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405946

RESUMO

Background: Next-generation sequencing (NGS) has proven to be a key implementation to understanding biological pathways involved in cancer. In daily practice, the identification of somatic and germline mutations has allowed physicians to gather relevant information to make therapeutic decisions and benefit patients. Importantly, somatic mutations provide targeted opportunities for treatment and reveal resistance mechanisms to understand patients' tumour evolution. Scanty data in clinical trials and in a real-world setting is available regarding the utility of poly(ADP-ribose) polymerase inhibitors in pathogenic or likely-pathogenic somatic breast cancer gene 1/2 (BRCA1/2) mutations and/or germline or somatic Homologous Recombination-Related Gene mutations in advanced breast cancer (ABC). Case report: Here we report a real-life case of a 47-year-old postmenopausal woman with hormone receptor-positive (HR-positive) Epidermal growth factor receptor 2 (HER2)-negative metastatic BC that had poor response to classic therapeutic strategies for HR+/HER2- ABC. At this point, the possibility of using NGS to guide the treatment was decided in a Molecular Tumour Board (MTB), and the patient had a major response to talazoparib targeting a non-germline BRCA2 mutation. Conclusion: Undoubtedly, more information regarding the cost effectiveness of NGS is needed to develop adequate reimbursement policies for this technology. It should be highlighted that the generalisation of MTBs and the implementation of molecular screening programmes are greatly needed in our region to gain more knowledge of somatic mutations implicated in the Hispanic and Latin-American population with BC diagnosis. Recently presented results of randomised studies may support the evaluation of somatic mutations with NGS to find targeted therapies for ABC patients.

4.
Rev. colomb. cancerol ; 25(4): 210-221, oct.-dic. 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1388944

RESUMO

Resumen La Hematopoyesis Clonal de Potencial Indeterminado (HCPI), más conocida como CHIP por sus siglas en inglés, se define como la expansión clonal de Células Madre Hematopoyéticas (CMHs) que albergan una o más mutaciones somáticas (en la mayoría de los casos una sola mutación) sin un cáncer hematológico subyacente ni evidencia morfológica definitiva de displasia, con una frecuencia alélica mayor al 2%. Los individuos con HCPI progresan a malignidad a una tasa de cerca del 0.5% a 1% por año, convirtiéndose así en un modelo de campo de cancerización. Sin embargo, sus implicaciones van más allá debido a que se ha encontrado asociación con enfermedades inflamatorias crónicas, como enfermedad cardiovascular ateroesclerótica, diabetes y enfermedades autoinmunes. Además, es considerado un factor predictivo en pacientes con cáncer hematolológico y no hematológico que reciben quimioterapia y radioterapia.


Abstract Clonal hematopoiesis of indeterminate potential (CHIP) is the expansion of hematopoietic stem cells harboring one or more somatic mutations. These patients do not have underlying hematologic neoplasia, myelodysplasia, or dysplasia, but can progress to a malignant state at a rate of 0.5 to 1% per year. CHIP could be used as a model of field cancerization, since it has been associated with chronic inflammatory diseases, arteriosclerosis, diabetes, and autoimmune conditions. CHIP is also considered a predictive factor in hematological and non-hematological cancer patients receiving chemotherapy and radiotherapy.


Assuntos
Humanos , Células-Tronco Hematopoéticas , Hematopoiese Clonal , Doenças Autoimunes , Tratamento Farmacológico , Mutação , Neoplasias
5.
Int J Biol Macromol ; 182: 1602-1610, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34033823

RESUMO

Phospholipase A2 Bothropstoxin-I (PLA2 BthTX-I) is a myotoxic Lys49-PLA2 from Bothrops jararacussu snake venom. In order to evaluate the DNA damage caused by BthTX-I, we used the Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster and Comet assay in HUVEC and DU-145 cells. For SMART, different concentrations of BthTX-I (6.72 to 430 µg/mL) were used and no significant changes in the survival rate were observed. Significant frequency of mutant spots was observed for the ST cross at the highest concentration of BthTX-I due to recombinogenic activity. In the HB cross, BthTX-I increased the number of mutant spots at intermediate concentrations, being 53.75 µg/mL highly mutagenic and 107.5 µg/mL predominantly recombinogenic. The highest concentrations were neither mutagenic nor recombinogenic, which could indicate cytotoxicity in the wing cells of D. melanogaster. In vitro, all BthTX-I concentrations (1 to 50 µg/mL) induced decrease in HUVEC cell viability, as well as in DU-145 cells at concentrations of 10, 25, and 50 µg/mL. The comet assay showed that in HUVEC and DU-145 cells, all BthTX-I concentrations promoted increase of DNA damage. Further studies should be performed to elucidate the mechanism of action of PLA2 BthTX-I and its possible use in therapeutic strategies against cancer.


Assuntos
Bothrops/metabolismo , Venenos de Crotalídeos/toxicidade , Fosfolipases A2/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Drosophila melanogaster , Células Endoteliais da Veia Umbilical Humana , Humanos , Mutação/genética
6.
Clinics ; Clinics;76: e2837, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1286084

RESUMO

OBJECTIVES: In breast cancer (BC) patients, the frequency of germline BRCA mutations (gBRCA) may vary according to the ethnic background, age, and family history of cancer. Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) is the second most common somatic mutated gene in BC; however, the association of mutations in both genes with cancer has not been thoroughly investigated. Thus, our aims were to investigate gBRCA mutation frequency in a cohort of postmenopausal Brazilian BC patients and the association of gBRCA1/BRCA2 and PIK3CA somatic mutations. METHODS: Forty-nine postmenopausal (>55 years) and forty-one young (≤35 years) BC patients were included in this study. The postmenopausal group included patients who reported a positive family history of cancer. For these patients, gBRCA1/BRCA2 were sequenced using next-generation sequencing (NGS) or Sanger sequencing. Data for gBRCA in young patients were already available from a previous study. DNA from formalin-fixed, paraffin-embedded (FFPE) tumors was obtained from 27 postmenopausal and 41 young patients for analyzing exons 9 and 20 of PIK3CA. The association between gBRCA1/BRCA2 and somatic mutations in PIK3CA was investigated. RESULTS: The overall frequency of gBRCA1/BRCA2 among the 49 postmenopausal patients was 10.2%. The frequencies of somatic mutations in PIK3CA in the postmenopausal and young patients were 37% and 17%, respectively (ns). The most common PIK3CA mutation was found to be E454A. Nonsense and frameshift mutations, which may counteract the oncogenic potential of PIK3CA were also detected. Regardless of age, 25% of BRCA1/BRCA2 mutation carriers and non-carriers , each, had PIK3CA somatic mutations. CONCLUSIONS: Data obtained indicate that BRCA1/BRCA2 gene testing may be considered for postmenopausal patients with BC who have a family history of cancer. Although some of them are not considered pathogenic, somatic variants of PIK3CA are frequently observed in BC patients, especially in postmenopausal patients.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias Ovarianas , Neoplasias da Mama/genética , Brasil , Pós-Menopausa , Mutação em Linhagem Germinativa , Predisposição Genética para Doença/genética , Células Germinativas , Mutação
7.
Genes (Basel) ; 11(11)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33227964

RESUMO

Triple-negative breast cancer (TNBC) presents a marked diversity at the molecular level, which promotes a clinical heterogeneity that further complicates treatment. We performed a detailed whole exome sequencing profile of 29 Mexican patients with long follow-up TNBC to identify genomic alterations associated with overall survival (OS), disease-free survival (DFS), and pathologic complete response (PCR), with the aim to define their role as molecular predictive factors of treatment response and prognosis. We detected 31 driver genes with pathogenic mutations in TP53 (53%), BRCA1/2 (27%), CDKN1B (9%), PIK3CA (9%), and PTEN (9%), and 16 operative mutational signatures. Moreover, tumors with mutations in BRCA1/2 showed a trend of sensitivity to platinum salts. We found an association between deficiency in DNA repair and surveillance genes and DFS. Across all analyzed tumors we consistently found a heterogeneous molecular complexity in terms of allelic composition and operative mutational processes, which hampered the definition of molecular traits with clinical utility. This work contributes to the elucidation of the global molecular alterations of TNBC by providing accurate genomic data that may help forthcoming studies to improve treatment and survival. This is the first study that integrates genomic alterations with a long follow-up of clinical variables in a Latin American population that is an underrepresented ethnicity in most of the genomic studies.


Assuntos
Mutação , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Adulto , Idoso , Distúrbios no Reparo do DNA/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfócitos do Interstício Tumoral/patologia , Pessoa de Meia-Idade , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Sequenciamento do Exoma
8.
Environ Toxicol Pharmacol ; 80: 103464, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32750419

RESUMO

The identification of substances that prevent or minimize the detrimental effects of ionizing radiation is an essential undertaking. The aim of this paper was to evaluate and compare the radioprotective potential of chlorophyllin, protoporphyrin and bilirubin, with amifostine®, an US Food & Drug Administration approved radioprotector Using the somatic mutation and recombination assay in the Drosophila melanogaster wing, it was found that pretreatment (1-9 h) with any of the porphyrins or amifostine® alone, did not affect the larva-adult viability or the basal frequency of mutation. However, they were associated with significant reductions in frequency of somatic mutation and recombination compared with the gamma-irradiated (20 Gy) control as follows: bilirubin (69.3 %)> chlorophyllin (40.0 %)> protoporphyrin (39.0 %)> amifostine® (19.7 %). Bilirubin also caused a 16 % increase in larva-adult viability with 3 h of pretreatment respect to percentage induced in 20 Gy control group. Whilst amifostine® was associated with lower genetic damage after pre-treatment of 1 and 3 h, this did not attain significance. These findings suggest that the tested porphyrins may have some potential as radioprotectant agents.


Assuntos
Amifostina/farmacologia , Bilirrubina/farmacologia , Clorofilídeos/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/efeitos da radiação , Protoporfirinas/farmacologia , Protetores contra Radiação/farmacologia , Animais , Drosophila melanogaster/genética , Feminino , Masculino , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Recombinação Genética/efeitos dos fármacos , Asas de Animais/efeitos dos fármacos , Asas de Animais/efeitos da radiação
9.
Food Chem Toxicol ; 138: 111228, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32112866

RESUMO

Betulinic acid (BA) is a pentacyclic triterpenoid found in several plant species. Urethane (URE) is a known promutagen. Here, we examine the genotoxicity and mutagenicity of BA alone or in combination with URE using the bone marrow micronucleus assay in mice bone marrow cells and the Somatic Mutation and Recombination Test in Drosophila melanogaster. Findings revealed that BA alone was not genotoxic, but reduced the frequency of micronucleus when compared to the positive control. No significant differences were observed in the cytotoxicity. Biochemical analyzes showed no significant differences for liver (AST and ALT) or renal (creatinine and urea) function parameters, indicating the absence of hepatotoxic and nephrotoxic effects. BA alone did not increase the frequency of mutant spots, but reduced the total frequency of mutant spots when co-administered with URE in both ST and HB crosses. In addition, BA reduced the recombinogenic effect of URE at the highest concentrations of both crosses. In conclusion, under experimental conditions, BA has modulatory effects on the genotoxicity induced by URE in mice, as well as in somatic cells of D. melanogaster. We suggest that the modulatory effects of BA may be mainly due to its antioxidant and apoptotic properties.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Mutagênese/efeitos dos fármacos , Triterpenos/farmacologia , Uretana/toxicidade , Animais , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Medula Óssea/efeitos dos fármacos , Carcinógenos/farmacologia , Drosophila melanogaster/genética , Feminino , Cabelo/efeitos dos fármacos , Masculino , Camundongos , Testes de Mutagenicidade , Triterpenos Pentacíclicos , Taxa de Sobrevida , Tricomas/efeitos dos fármacos , Triterpenos/química , Asas de Animais/efeitos dos fármacos , Ácido Betulínico
10.
Environ Mol Mutagen ; 61(3): 329-337, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31489703

RESUMO

Medicinal plants are worldwide used as an efficient treatment of many diseases. Myracrodruon urundeuva Allemão (Anacardiaceae) is widely used Brazilian folk medicine to treat inflammations and infections of the female genital tract, conditions of the stomach and throat, and to heal wounds on the skin and mucous membranes. Several pharmacological properties of extracts and compounds isolated from M. urundeuva are found in the literature, corroborating its uses as antiulcer and gastroprotective, anti-inflammatory and analgesic, as well as antimicrobial. Despite these many uses in traditional herbal medicine, there are few reports of its toxic-genetic effect. This work aimed to investigate the genotoxic and mutagenic potential in vivo of the dry decoction of M. urundeuva leaves on somatic cells of Drosophila melanogaster, through the Comet assay and somatic mutation and recombination test (SMART). Six concentrations (0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 mg/mL) were studied after feeding individuals for 24 hr in culture medium hydrated with extracts of M. urundeuva. In the Comet assay, all concentrations showed a genotoxic effect significantly higher than the negative control group, treated with distilled water. The two highest concentrations were also superior to the positive control group, treated with cyclophosphamide (1 mg/mL). In the SMART, there was a mutagenic effect at all concentrations tested, with a clear dose-dependent relationship. Both recombination and mutation account for these mutagenic effects. The set of results indicate that the dry decoction of M. urundeuva leaves is genotoxic and mutagenic for D. melanogaster under the experimental conditions of this study. Environ. Mol. Mutagen. 61:329-337, 2020. © 2019 Wiley Periodicals, Inc.


Assuntos
Anacardiaceae/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Testes de Mutagenicidade , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Anti-Inflamatórios/toxicidade , Brasil , Ensaio Cometa , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Medicina Tradicional , Mutação/efeitos dos fármacos , Folhas de Planta/toxicidade
11.
Food Chem Toxicol ; 131: 110557, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176925

RESUMO

The aim of the present study was to appraise the mutagenic and recombinogenic potential of bupropion hydrochloride (BHc) and trazodone hydrochloride (THc). We used standard (ST) and the high bioactivation (HB) crossings from Drosophila melanogaster in the Somatic Mutation and Recombination Test. We treated third-instar larvae from both crossings with different concentrations of BHc and THc (0.9375 to 7.5 mg/mL). BHc significantly increased the frequency of mutant spots in both crossings, except for the lowest concentration in the ST crossing. ST had also the mostly recombinogenic result, and in the HB, BHc was highly mutagenic. On the other hand, THc significantly increased the frequency of mutant spots in both the ST and HB crossings at all concentrations. The three initial concentrations were recombinogenic and the highest concentration was mutagenic for the THc. BHc and THc at high concentrations were toxic, even though their mutagenicity was not dose-related. THc significantly increased the frequency of mutant spots when metabolized, probably as a result of the production of 1-(3'-chlorophenyl) piperazine. BHc was essentially recombinogenic and when metabolized, it became mutagenic. THc was recombinogenic in both crossings. Further studies are needed to clarify the action mechanisms from BHc and THc.


Assuntos
Antidepressivos/toxicidade , Bupropiona/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Mutagênicos/toxicidade , Recombinação Genética/efeitos dos fármacos , Trazodona/toxicidade , Animais , Drosophila melanogaster/genética , Feminino , Masculino , Testes de Mutagenicidade , Mutação , Asas de Animais/efeitos dos fármacos
12.
J Neurosci Res ; 97(9): 1141-1152, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30985022

RESUMO

Cancer is a major concern for contemporary societies. However, the incidence of cancer is unevenly distributed among tissues and cell types. In particular, the evidence indicates that neurons are absolutely resistant to cancer and this is commonly explained on the basis of the known postmitotic state of neurons. The dominant paradigm on cancer understands this problem as a disease caused by mutations in cellular genes that result in unrestrained cell proliferation and eventually in tissue invasion and metastasis. However, the evidence also shows that mutations and gross chromosomal anomalies are common in functional neurons that nevertheless do not become neoplastic. This fact suggests that in the real nonexperimental setting mutations per se are not enough for inducing carcinogenesis but also that the postmitotic state of neurons is not genetically controlled or determined, otherwise there should be reports of spontaneously transformed neurons. Here we discuss the evidence that the postmitotic state of neurons has a structural basis on the high stability of their nuclear higher order structure that performs like an absolute tumor suppressor. We also discuss evidence that it is possible to induce a similar structural postmitotic state in nonneural cell types as a practical strategy for stopping or reducing the progression of cancer.


Assuntos
Mitose , Neoplasias/metabolismo , Neurônios/metabolismo , Animais , Núcleo Celular , Humanos , Mutação
13.
Environ Toxicol Pharmacol ; 62: 210-214, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30081379

RESUMO

Many studies have revealed that ascorbic acid (Aa) acts as a powerful inhibitor of genetic damage. The objetive of the present study was to evaluate the radioprotector effect of Aa at two diferent radiation dose rates. The somatic mutation and recombination test in Drosophila melanogaster was used. 48 h larvae were treated for 24 h with 25, 50 and 100 mM of Aa. After pretreatment, larvae were irradiated with 20 Gy of gamma rays administered at 36 or 960 Gy/h. Toxicity, development rate and frequency of mutant spots were recorded. Results provide evidence of a radioprotective effect for all tested concentrations of Aa only when 20 Gy were delivered at 36 Gy/h and only with 25 mM using the 960 Gy/h. To consider the use of Aa as radioprotector or therapeutic agent, it is necessary to know its potential under different situations to avoid unwanted injuries.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Raios gama/efeitos adversos , Protetores contra Radiação/farmacologia , Animais , Dano ao DNA , Relação Dose-Resposta à Radiação , Drosophila melanogaster/genética , Drosophila melanogaster/efeitos da radiação , Feminino , Larva/efeitos dos fármacos , Larva/genética , Larva/efeitos da radiação , Masculino , Mutação , Asas de Animais/anormalidades , Asas de Animais/efeitos dos fármacos , Asas de Animais/efeitos da radiação
14.
Oncotarget ; 9(32): 22460-22479, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29854292

RESUMO

Breast cancer arising in very young patients may be biologically distinct; however, these tumors have been less well studied. We characterized a group of very young patients (≤ 35 years) for BRCA germline mutation and for somatic mutations in luminal (HER2 negative) breast cancer. Thirteen of 79 unselected very young patients were BRCA1/2 germline mutation carriers. Of the non-BRCA tumors, eight with luminal subtype (HER2 negative) were submitted for whole exome sequencing and integrated with 29 luminal samples from the COSMIC database or previous literature for analysis. We identified C to T single nucleotide variants (SNVs) as the most common base-change. A median of six candidate driver genes was mutated by SNVs in each sample and the most frequently mutated genes were PIK3CA, GATA3, TP53 and MAP2K4. Potential cancer drivers affected in the present non-BRCA tumors include GRHL2, PIK3AP1, CACNA1E, SEMA6D, SMURF2, RSBN1 and MTHFD2. Sixteen out of 37 luminal tumors (43%) harbored SNVs in DNA repair genes, such as ATR, BAP1, ERCC6, FANCD2, FANCL, MLH1, MUTYH, PALB2, POLD1, POLE, RAD9A, RAD51 and TP53, and 54% presented pathogenic mutations (frameshift or nonsense) in at least one gene involved in gene transcription. The differential biology of luminal early-age onset breast cancer needs a deeper genomic investigation.

15.
Food Chem Toxicol ; 112: 273-281, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29292020

RESUMO

Nanoparticles have been widely used in several sectors and their long-term effect on the body and environment remains unknown. To evaluate the mutagenic, recombinogenic and carcinogenic potential of 11 nm titanium dioxide nanocrystals (TiO2 NCs), the Somatic Mutation and Recombination Test (SMART) and the Test for Detection of Epithelial Tumors Clones (Warts-Wts) were used, both in Drosophila melanogaster. Third-instar larvae (72 + 4 h), obtained in both tests, were treated with different concentrations of TiO2 NCs ranging from 6.25 to 100 mM. Ultrapure water and urethane were used as negative and positive controls, respectively. At ST cross, all concentrations of TiO2 NCs showed a significant increase in the frequencies of mutant spots, demonstrating higher recombination rates. At the HB cross, only the 50 mM concentration showed a negative result. In the Wts Test, all used concentrations were carcinogenic, except for the 100 mM one, which was toxic. No relationship was demonstrated between the used concentrations and the obtained responses. There was no interference of the cytochrome P450 enzyme complex in the induction of mutant spots.


Assuntos
Carcinógenos/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Titânio/toxicidade , Animais , Drosophila melanogaster/genética , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Recombinação Genética/efeitos dos fármacos
16.
Rev. chil. dermatol ; 34(1): 24-28, 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-965812

RESUMO

El síndrome de Proteus corresponde a una entidad poco frecuente caracterizada por un sobrecrecimiento progresivo de piel, tejido óseo y adiposo, debido a una mutación somática activante del gen AKT1. Existen distintas manifestaciones cutáneas entre las que se incluyen nevo cerebriforme de tejido conectivo plantar, nevo epidérmico, malformaciones vasculares y trastornos del tejido adiposo que pueden alertar al dermatólogo para poder diagnosticar esta condición, permitiendo un manejo precoz que impida el desarrollo de complicaciones y la muerte temprana. Presentamos el caso de una paciente de 9 años cuya historia clínica y examen físico reflejan los hallazgos clásicos del síndrome de Proteus, recalcando la importancia de un manejo multidisciplinario oportuno.


Proteus syndrome is a rare condition characterized by a progressive overgrowth of skin, bone tissue and adipose tissue, due to an activating somatic mutation of the AKT1 gene. Different cutaneous manifestations that include cerebriform connective tissue nevi, epidermal nevus, vascular malformations and adipose tissue disorders can alert the dermatologist to diagnose this condition, allowing an early management that prevents the complications and early death. We present the case of a 9-year-old patient whose clinical history and physical examination reflect the classic findings of Proteus syndrome, highlighting the importance of a multidisciplinary management.


Assuntos
Humanos , Feminino , Criança , Síndrome de Proteu/diagnóstico , Mutação
17.
Food Chem Toxicol ; 106(Pt A): 283-291, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28571774

RESUMO

Metformin (MET) is an anti-diabetic drug used to prevent hepatic glucose release and increase tissue insulin sensitivity. Diabetic cancer patients are on additional therapy with anticancer drugs. Doxorubicin (DXR) is a cancer chemotherapeutic agent that interferes with the topoisomerase II enzyme and generates free radicals. MET (2.5, 5, 10, 25 or 50 mM) alone was examined for mutagenicity, recombinogenicity and carcinogenicity, and combined with DXR (0.4 mM) for antimutagenicity, antirecombinogenicity and anticarcinogenicity, using the Somatic Mutation and Recombination Test and the Test for Detecting Epithelial Tumor Clones in Drosophila melanogaster. MET alone did not induce mutation or recombination. Modulating effects of MET on DXR-induced DNA damage were observed at the highest concentrations. In the evaluation of carcinogenesis, MET alone did not induce tumors. When combined with DXR, MET also reduced the DXR-induced tumors at the highest concentrations. Therefore, in the present experimental conditions, MET alone did not present mutagenic/recombinogenic/carcinogenic effects, but it was able to modulate the effect of DXR in the induction of DNA damage and of tumors in D. melanogaster. It is believed that this modulating effect is mainly related to the antioxidant, anti-inflammatory and apoptotic effects of this drug, although such effects have not been directly evaluated.


Assuntos
Doxorrubicina/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Metformina/farmacologia , Mutagênicos/toxicidade , Animais , Carcinogênese/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Metformina/administração & dosagem , Testes de Mutagenicidade , Mutagênicos/administração & dosagem , Mutação/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Recombinação Genética/efeitos dos fármacos
18.
J Med Food ; 20(6): 601-609, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28541831

RESUMO

Vitexin is a C-glycosylated flavone found in various medicinal plants with several proven biological properties such as anti-inflammatory, antispasmodic, antimicrobial, cytotoxic, and antioxidant activities. Considering that the human population consumes many foods that contain this flavonoid, the objective of this study was to investigate the genotoxic and the antigenotoxic potentials of vitexin by the SMART (Somatic Mutation and Recombination Test) in Drosophila melanogaster wings, in vivo. To evaluate the genotoxic activity, larvae obtained from standard (ST) and high bioactivation (HB) crosses were chronically treated with different concentrations of vitexin (0.15, 0.3, and 0.6 mM). For the evaluation of antigenotoxic activity, the same vitexin concentrations were associated with two damage inducing agents: doxorubicin (0.2 mM) and benzo[a]pyrene (1.0 mM). The results obtained for genotoxic activity showed that vitexin did not induce a statistically significant increment in the frequency of mutant spots, when compared to control. The results for the evaluation of antigenotoxicity indicated that the flavonoid statistically reduced the frequency of mutant spots, when compared to those treated with only the damage inducing agents. Thus, this article presents results that have demonstrated the antigenotoxic activity of vitexin, which could be applied in new studies for the development of drugs with chemoprotective effects.


Assuntos
Antimutagênicos/farmacologia , Apigenina/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/genética , Flavonoides/farmacologia , Mutagênicos/toxicidade , Recombinação Genética/efeitos dos fármacos , Animais , Dano ao DNA/efeitos dos fármacos , Feminino , Masculino , Testes de Mutagenicidade
19.
Appl. cancer res ; 37: 1-8, 2017. ilus
Artigo em Inglês | LILACS, Inca | ID: biblio-915111

RESUMO

Current strategies for cancer patient management include the use of genomic and proteomic test results to help guide therapeutic selection. The need for multi-target variant analysis is highlighted by the growing number of novel therapies to treat tumors with specific profiles and the increasing recognition that cancer is an extremely heterogeneous syndrome. Microarray analysis is a powerful genomic tool that provides genome-wide genetic information that is critical for guiding cancer treatments. Unlike constitutional applications of microarray analysis which are performed on whole blood samples, microarray analysis of solid tumors is challenging because tumor tissues are typically formalin fixed and paraffin embedded (FFPE). Genomic DNA extracted from FFPE tissues can also be fragmented into small pieces and yield much lower concentrations of DNA. We validated and implemented the Affymetrix OncoScan® FFPE assay to enable genome-wide analysis from these types of samples. The Affymetrix OncoScan® assay utilizes molecular inversion probes that generate multiplexed array hybridization targets from as short as 40 base-pairs of sequence and as low as approximately 80 ng of genomic DNA. OncoScan microarray analysis provides genomic information that includes structural variations, copy number variations and SNPs in a timely and a cost-effective manner from FFPE tumor tissues (AU)


Assuntos
Humanos , Hibridização in Situ Fluorescente , Genômica , Proteômica , Análise em Microsséries , Diagnóstico , Neoplasias/diagnóstico , Hibridização de Ácido Nucleico
20.
Chemosphere ; 165: 342-351, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27664524

RESUMO

Fipronil (FP) is an insecticide that belongs to the phenylpyrazole chemical family and is used to control pests by blocking GABA receptor at the entrance channel of the chlorine neurons. The aim of this study was to evaluate the mutagenic, recombinogenic and carcinogenic potential of FP. The mutagenic and recombinogenic effects were evaluated using the somatic mutation and recombination test (SMART) on wing cells of Drosophila melanogaster. Third instar larvae from standard (ST) and high bioactivation (HB) crosses were treated with different concentrations of FP (0.3, 0.7, 1.5 or 3.0 × 10-5 mM). The results showed mutagenic effects at all concentrations tested in the HB cross; and all concentrations tested in the ST cross, except at concentration of 0.7 × 10-5 mM. The carcinogenic effect of FP was assayed through the test for detection of epithelial tumor (warts) in D. melanogaster. Third instar larvae from wts/TM3 virgin females mated to mwh/mwh males were treated with different concentrations of FP (0.3, 0.7, 1.5 or 3.0 × 10-5 mM). All these concentrations induced a statistically significant increase in tumor frequency. In conclusion, FP proved to be mutagenic, recombinogenic and carcinogenic in somatic cells of D. melanogaster.


Assuntos
Carcinógenos/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Inseticidas/toxicidade , Testes de Mutagenicidade/métodos , Neoplasias/induzido quimicamente , Pirazóis/toxicidade , Asas de Animais/patologia , Animais , Feminino , Larva/efeitos dos fármacos , Masculino , Mutagênese , Mutagênicos/toxicidade , Recombinação Genética/efeitos dos fármacos , Asas de Animais/efeitos dos fármacos
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