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1.
Int J Biol Macromol ; 275(Pt 2): 133731, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38986978

RESUMO

l-asparaginases play a crucial role in the treatment of acute lymphoblastic leukemia (ALL), a type of cancer that mostly affects children and teenagers. However, it is common for these molecules to cause adverse reactions during treatment. These downsides ignite the search for novel asparaginases to mitigate these problems. Thus, this work aimed to produce and characterize a recombinant asparaginase from Phaseolus vulgaris (Asp-P). In this study, Asp-P was expressed in Escherichia coli with high yields and optimum activity at 40 °C, pH 9.0. The enzyme Km and Vmax values were 7.05 mM and 1027 U/mg, respectively. Asp-P is specific for l-asparagine, showing no activity against l-glutamine and other amino acids. The enzyme showed a higher cytotoxic effect against Raji than K562 cell lines, but only at high concentrations. In silico analysis indicated that Asp-P has lower immunogenicity than a commercial enzyme. Asp-P induced biofilm formation by Candida sp. due to sublethal dose, showing an underexplored potential of asparaginases. The absence of glutaminase activity, lower immunogenicity and optimal activity similar to physiological temperature conditions are characteristics that indicate Asp-P as a potential new commercial enzyme in the treatment of ALL and its underexplored application in the treatment of other diseases.


Assuntos
Asparaginase , Phaseolus , Proteínas Recombinantes , Asparaginase/química , Asparaginase/farmacologia , Asparaginase/genética , Asparaginase/imunologia , Phaseolus/química , Humanos , Cinética , Proteínas Recombinantes/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Leucemia/tratamento farmacológico , Células K562 , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Temperatura
2.
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.

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
4.
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
5.
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
6.
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
7.
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
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