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1.
Front Cell Dev Biol ; 11: 1116805, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36866275

RESUMO

Disruption of the epigenetic program of gene expression is a hallmark of cancer that initiates and propagates tumorigenesis. Altered DNA methylation, histone modifications and ncRNAs expression are a feature of cancer cells. The dynamic epigenetic changes during oncogenic transformation are related to tumor heterogeneity, unlimited self-renewal and multi-lineage differentiation. This stem cell-like state or the aberrant reprogramming of cancer stem cells is the major challenge in treatment and drug resistance. Given the reversible nature of epigenetic modifications, the ability to restore the cancer epigenome through the inhibition of the epigenetic modifiers is a promising therapy for cancer treatment, either as a monotherapy or in combination with other anticancer therapies, including immunotherapies. Herein, we highlighted the main epigenetic alterations, their potential as a biomarker for early diagnosis and the epigenetic therapies approved for cancer treatment.

2.
3 Biotech ; 12(12): 344, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36382241

RESUMO

The current outbreak of COVID-19 cases worldwide has been responsible for a significant number of deaths, especially in hospitalized patients suffering from comorbidities, such as obesity, diabetes, hypertension. The disease not only has prompted an interest in the pathophysiology, but also it has propelled a massive race to find new anti-SARS-CoV-2 drugs. In this scenario, known drugs commonly used to treat other diseases have been suggested as alternative or complementary therapeutics. Herein we propose the use of sitagliptin, an inhibitor of dipeptidyl peptidase-4 (DPP4) used to treat type-II diabetes, as an agent to block and inhibit the activity of two proteases, 3CLpro and PLpro, related to the processing of SARS-CoV-2 structural proteins. Inhibition of these proteases may possibly reduce the viral load and infection on the host by hampering the synthesis of new viruses, thus promoting a better outcome. In silico assays consisting in the modeling of the ligand sitagliptin and evaluation of its capacity to interact with 3CLpro and PLpro through the prediction of the ligand bioactivity, molecular docking, overlapping of crystal structures, and molecular dynamic simulations were conducted. The experiments indicate that sitagliptin can interact and bind to both targets. However, this interaction seems to be stronger and more stable to 3CLpro (ΔG = -7.8 kcal mol-1), when compared to PLpro (ΔG = -7.5 kcal mol-1). This study suggests that sitagliptin may be suitable to treat COVID-19 patients, beyond its common use as an anti-diabetic medication. In vivo studies may further support this hypothesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03406-w.

3.
Clin Epigenetics ; 14(1): 133, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284309

RESUMO

BACKGROUND: Penile cancer is one of the most aggressive male tumors. Although it is preventable, the main etiologic causes are lifestyle behaviors and viral infection, such as human papillomavirus (HPV). Long-term epigenetic changes due to environmental factors change cell fate and promote carcinogenesis, being an important marker of prognosis. We evaluated epidemiological aspects of penile squamous cell carcinoma (SCC) and the prevalence of HPV infection using high-risk HPV (hrHPV) and p16INK4A expression of 224 participants. Global DNA methylation was evaluated through 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). RESULTS: The incidence of HPV was 53.2% for hrHPV and 22.32% for p16INK4a. hrHPV was not related to systemic or lymph node metastasis and locoregional recurrence, nor influenced the survival rate. P16INK4a seems to be a protective factor for death, which does not affect metastasis or tumor recurrence. Lymph node and systemic metastases and locoregional recurrence increase the risk of death. An increased 5mC mark was observed in penile SCC regardless of HPV infection. However, there is a reduction of the 5hmC mark for p16INK4a + (P = 0.024). Increased 5mC/5hmC ratio (> 1) was observed in 94.2% of penile SCC, irrespective of HPV infection. Despite the increase in 5mC, it seems not to affect the survival rate (HR = 1.06; 95% CI 0.33-3.38). CONCLUSIONS: P16INK4a seems to be a good prognosis marker for penile SCC and the increase in 5mC, an epigenetic mark of genomic stability, may support tumor progression leading to poor prognosis.


Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Neoplasias Penianas , Masculino , Humanos , Neoplasias Penianas/genética , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/patologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/epidemiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Prognóstico , 5-Metilcitosina , Metilação de DNA , Recidiva Local de Neoplasia/genética , Papillomaviridae/genética , Carcinoma de Células Escamosas/metabolismo , Alphapapillomavirus/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Epigênese Genética , DNA Viral
5.
Reprod Sci ; 29(3): 680-694, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33826098

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders, affecting approximately 5-20% of women of reproductive age. PCOS is a multifactorial, complex, and heterogeneous disease, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries, which may lead to impaired fertility. Besides the reproductive outcomes, multiple comorbidities, such as metabolic disturbances, insulin resistance, obesity, diabetes, and cardiovascular disease, are associated with PCOS. In addition to the clear genetic basis, epigenetic alterations may also play a central role in PCOS outcomes, as environmental and hormonal alterations directly affect clinical manifestations and PCOS development. Here, we highlighted the epigenetic modifications in the multiplicity of clinical manifestations, as well as environmental epigenetic disruptors, as intrauterine hormonal and metabolic alterations affecting embryo development and the adulthood lifestyle, which may contribute to PCOS development. Additionally, we also discussed the new approaches for future studies and potential epigenetic biomarkers for the treatment of associated comorbidities and improvement in quality of life of women with PCOS.


Assuntos
Epigênese Genética , Síndrome do Ovário Policístico/genética , Adulto , Feminino , Humanos
6.
Sci Rep ; 11(1): 18380, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526543

RESUMO

The imprinted H19 long non-coding RNA, a knowing oncofetal gene, presents a controversial role during the carcinogenesis process since its tumor suppressor or oncogenic activity is not completely elucidated. Since H19 lncRNA is involved in many biological pathways related to tumorigenesis, we sought to develop a non-cancer lineage with CRISPR-Cas9-mediated H19 knockdown (H19-) and observe the changes in a cellular context. To edit the promoter region of H19, two RNA guides were designed, and the murine C2C12 myoblast cells were transfected. H19 deletion was determined by DNA sequencing and gene expression by qPCR. We observed a small deletion (~ 60 bp) in the promoter region that presented four predicted transcription binding sites. The deletion reduced H19 expression (30%) and resulted in increased proliferative activity, altered morphological patterns including cell size and intracellular granularity, without changes in viability. The increased proliferation rate in the H19- cell seems to facilitate chromosomal abnormalities. The H19- myoblast presented characteristics similar to cancer cells, therefore the H19 lncRNA may be an important gene during the initiation of the tumorigenic process. Due to CRISPR/Cas9 permanent edition, the C2C12 H19- knockdown cells allows functional studies of H19 roles in tumorigenesis, prognosis, metastases, as well as drug resistance and targeted therapy.


Assuntos
Sistemas CRISPR-Cas , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Deleção de Sequência , Animais , Sequência de Bases , Biomarcadores Tumorais , Carcinogênese/genética , Ciclo Celular/genética , Proliferação de Células/genética , Análise Citogenética , Edição de Genes , Técnicas de Silenciamento de Genes , Humanos , Camundongos , RNA Longo não Codificante/química
7.
ChemMedChem ; 16(2): 420-428, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-32886437

RESUMO

The tambjamines are a small group of bipyrrolic alkaloids that, collectively, display a significant range of biological activities including antitumor, antimicrobial and immunosuppressive properties. The key objective of the present study was to undertake preclinical assessments of tambjamine J (T-J) so as to determine its in vivo antitumor effects. To that end, sarcoma 180 cells were transplanted in mice and the impacts of the title compound then evaluated using a range of protocols including hematological, biochemical, histopathological, genotoxic and clastogenic assays. As a result it was established that this alkaloid has a significant therapeutic window and effectively reduces tumor growth (by 40 % and 79 % at doses of 10 and 20 mg/kg/day, respectively). In this regard it displays similar antitumor activity to the anticancer agent cyclophosphamide and alters animal weight in an analogous manner.


Assuntos
Antineoplásicos/farmacologia , Sarcoma 180/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Masculino , Camundongos , Estrutura Molecular , Sarcoma 180/patologia
8.
Curr Med Chem ; 28(13): 2485-2520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32484100

RESUMO

Targeted therapy has been recently highlighted due to the reduction of side effects and improvement in overall efficacy and survival from different types of cancers. Considering the approval of many monoclonal antibodies in the last twenty years, cancer treatment can be accomplished by the combination of monoclonal antibodies and small molecule chemotherapeutics. Thus, strategies to combine both drugs in a single administration system are relevant in the clinic. In this context, two strategies are possible and will be further discussed in this review: antibody-drug conjugates (ADCs) and antibody-functionalized nanoparticles. First, it is important to better understand the possible molecular targets for cancer therapy, addressing different antigens that can selectively bind to antibodies. After selecting the best target, ADCs can be prepared by attaching a cytotoxic drug to an antibody able to target a cancer cell antigen. Briefly, an ADC will be formed by a monoclonal antibody (MAb), a cytotoxic molecule (cytotoxin) and a chemical linker. Usually, surface-exposed lysine or the thiol group of cysteine residues are used as anchor sites for linker-drug molecules. Another strategy that should be considered is antibody-functionalized nanoparticles. Basically, liposomes, polymeric and inorganic nanoparticles can be attached to specific antibodies for targeted therapy. Different conjugation strategies can be used, but nanoparticles coupling between maleimide and thiolated antibodies or activation with the addition of ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/ N-hydroxysuccinimide (NHS) (1:5) and further addition of the antibody are some of the most used strategies. Herein, molecular targets and conjugation strategies will be presented and discussed to better understand the in vitro and in vivo applications presented. Also, the clinical development of ADCs and antibody-conjugated nanoparticles are addressed in the clinical development section. Finally, due to the innovation related to the targeted therapy, it is convenient to analyze the impact on patenting and technology. Information related to the temporal evolution of the number of patents, distribution of patent holders and also the number of patents related to cancer types are presented and discussed. Thus, our aim is to provide an overview of the recent developments in immunoconjugates for cancer targeting and highlight the most important aspects for clinical relevance and innovation.


Assuntos
Antineoplásicos , Imunoconjugados , Nanopartículas , Neoplasias , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Humanos , Imunoconjugados/uso terapêutico , Neoplasias/tratamento farmacológico
9.
Diabetol Metab Syndr ; 12: 28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280377

RESUMO

BACKGROUND: Congenital generalized lipodystrophy (CGL) is a rare autosomal recessive disorder characterized by the near-total loss of subcutaneous adipose tissue soon after birth, resulting in ectopic fat deposition and severe metabolic disturbances. Most cases are caused by AGPAT2 or BSCL2 gene mutations. We aimed to report two unrelated CGL patients with a novel frameshift mutation in AGPAT2 (p.Leu124Serfs*26). METHODS: Clinical features and laboratory were obtained by medical interview and medical records review. DNA was extracted, amplified and sequenced. Mutation Taster was used to estimate the potential biological impact of the AGPAT2 mutations on the protein function. RESULTS: Patient 1: a 30-year-old woman with lipodystrophy phenotype at birth and diagnosis of diabetes at age 13 presented with severe hypertriglyceridemia and pancreatitis at age 17, hypertension and albuminuria at age 18, proliferative diabetic retinopathy with visual loss at age 25, and an acute myocardial infarction due to multivessel coronary disease during a hospitalization for forefoot amputation at age 29. At this time, she required hemodialysis due to end-stage renal disease. Patient 2: a 12-year-old girl with lipodystrophy phenotype and hypertriglyceridemia detected in the first year of life and abnormalities in the global longitudinal strain, evaluated by speckle-tracking echocardiography last year. Molecular analysis identified a c.369_372delGCTC (p.Leu124Serfs*26) AGPAT2 mutation in both unrelated patients, a compound heterozygous mutation in Patient 1, and homozygous mutation in Patient 2. CONCLUSION: We describe two unrelated patients with type 1 CGL due to Leu124Serfs*26, a novel AGPAT2 frameshift mutation, presenting as early cardiovascular disease. These findings suggest an association between Leu124Serfs*26 and a more aggressive phenotype.

10.
Horm Res Paediatr ; 84(4): 248-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26304632

RESUMO

BACKGROUND/AIM: The single nucleotide polymorphisms (SNPs) rs2282978 (CDK6), rs2425019 (MMP24), rs8081612 (MAP3K3), rs2871865 (IGF1R) and rs3782415 (SOCS2) were among the SNPs most strongly associated with height in a meta-analysis of 47 genome-wide association studies (GWAS) involving 114,223 adults from six ethnic groups. The present study aimed to examine associations between these SNPs and height in Brazilian children. METHODS: Cross-sectional heights of 1,008 healthy unrelated 4.4- to 9.7-year-old children were evaluated. All genotypes were determined by allele-specific polymerase chain reactions. Height standard deviation scores (SDS) were generated for this population and regressed on allele counts. Linear regressions were performed to estimate the effect of individual SNPs or a polygenic allelic score on height. RESULTS: The T allele of rs8081612 (MAP3K3), the C allele of rs2871865 (IGF1R) and the G allele of rs2425019 (MMP24) were significantly associated with a 0.091-SDS greater height (95% CI 0.089-0.093, p = 0.001) by polygenic analysis. The mean height SDS difference between children with 2 'tall' alleles and children with 4 'tall' alleles was 0.24 SDS (95% CI 0.05-0.43, p = 0.01). The observed allelic effect is consistent with that found in previous GWAS. CONCLUSIONS: Polymorphisms in MAP3K3, MMP24 and IGF1R act additively on height in children of an admixed population. These results demonstrate the importance of these loci for children's height.


Assuntos
Estatura/genética , Loci Gênicos , MAP Quinase Quinase Quinase 3/genética , Metaloproteinases da Matriz Associadas à Membrana/genética , Polimorfismo de Nucleotídeo Único , Receptores de Somatomedina/genética , Alelos , Brasil , Criança , Pré-Escolar , Estudos Transversais , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Receptor IGF Tipo 1
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