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1.
PLoS One ; 19(4): e0299993, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568963

RESUMO

The selection of proper reference genes is critical for accurate gene expression analysis in all fields of biological and medical research, mainly because there are many distinctions between different tissues and specimens. Given this variability, even in known classic reference genes, demands of a comprehensive analysis platform is needed to identify the most suitable genes for each study. For this purpose, we present an analysis tool for assisting in decision-making in the analysis of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) data. EndoGeneAnalyzer, an open-source web tool for reference gene analysis in RT-qPCR studies, was used to compare the groups/conditions under investigation. This interactive application offers an easy-to-use interface that allows efficient exploration of datasets. Through statistical and stability analyses, EndoGeneAnalyzer assists in the select of the most appropriate reference gene or set of genes for each condition. It also allows researchers to identify and remove unwanted outliers. Moreover, EndoGeneAnalyzer provides a graphical interface to compare the evaluated groups, providing a visually informative differential analysis.


Assuntos
Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa
2.
Genes (Basel) ; 15(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38397141

RESUMO

Reference genes are used as internal reaction controls for gene expression analysis, and for this reason, they are considered reliable and must meet several important criteria. In view of the absence of studies regarding the best reference gene for the analysis of acute leukemia patients, a panel of genes commonly used as endogenous controls was selected from the literature for stability analysis: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Abelson murine leukemia viral oncogene human homolog 1 (ABL), Hypoxanthine phosphoribosyl-transferase 1 (HPRT1), Ribosomal protein lateral stalk subunit P0 (RPLP0), ß-actin (ACTB) and TATA box binding protein (TBP). The stability of candidate reference genes was analyzed according to three statistical methods of assessment, namely, NormFinder, GeNorm and R software (version 4.0.3). From this study's analysis, it was possible to identify that the endogenous set composed of ACTB, ABL, TBP and RPLP0 demonstrated good performances and stable expressions between the analyzed groups. In addition to that, the GAPDH and HPRT genes could not be classified as good reference genes, considering that they presented a high standard deviation and great variability between groups, indicating low stability. Given these findings, this study suggests the main endogenous gene set for use as a control/reference for the gene expression in peripheral blood and bone marrow samples from patients with acute leukemias is composed of the ACTB, ABL, TBP and RPLP0 genes. Researchers may choose two to three of these housekeeping genes to perform data normalization.


Assuntos
Perfilação da Expressão Gênica , Leucemia , Camundongos , Animais , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Genes Essenciais , Gliceraldeído-3-Fosfato Desidrogenases/genética , Doença Aguda , Leucemia/genética , Expressão Gênica
3.
Cancer Diagn Progn ; 4(1): 9-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38173664

RESUMO

Leukemias are hematological neoplasms characterized by dysregulations in several cellular signaling pathways, prominently including the PI3K/AKT/mTOR pathway. Since this pathway is associated with several important cellular mechanisms, such as proliferation, metabolism, survival, and cell death, its hyperactivation significantly contributes to the development of leukemias. In addition, it is a crucial prognostic factor, often correlated with therapeutic resistance. Changes in the PI3K/AKT/mTOR pathway are identified in more than 50% of cases of acute leukemia, especially in myeloid lineages. Furthermore, these changes are highly frequent in cases of chronic lymphocytic leukemia, especially those with a B cell phenotype, due to the correlation between the hyperactivation of B cell receptors and the abnormal activation of PI3Kδ. Thus, the search for new therapies that inhibit the activity of the PI3K/AKT/mTOR pathway has become the objective of several clinical studies that aim to replace conventional oncological treatments that have high rates of toxicities and low specificity with target-specific therapies offering improved patient quality of life. In this review we describe the PI3K/AKT/mTOR signal transduction pathway and its implications in leukemogenesis. Furthermore, we provide an overview of clinical trials that employed PI3K/AKT/mTOR inhibitors either as monotherapy or in combination with other cytotoxic agents for treating patients with various types of leukemias. The varying degrees of treatment efficacy are also reported.

4.
Cancers (Basel) ; 15(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067214

RESUMO

Detection of t(9;22), and consequent BCR::ABL1 fusion, is still a marker of worse prognosis for acute lymphoblastic leukemia (ALL), with resistance to tyrosine-kinase inhibitor therapy being a major obstacle in the clinical practice for this subset of patients. In this study, we investigated the effectiveness of targeting poly-ADP-ribose polymerase (PARP) in a model of BCR::ABL1 p190+ ALL, the most common isoform to afflict ALL patients, and demonstrated the use of experimental PARP inhibitor (PARPi), AZD2461, as a therapeutic option with cytotoxic capabilities similar to that of imatinib, the current gold standard in medical care. We characterized cytostatic profiles, induced cell death, and biomarker expression modulation utilizing cell models, also providing a comprehensive genome-wide analysis through an aCGH of the model used, and further validated PARP1 differential expression in samples of ALL p190+ patients from local healthcare institutions, as well as in larger cohorts of online and readily available datasets. Overall, we demonstrate the effectiveness of PARPi in the treatment of BCR::ABL1 p190+ ALL cell models and that PARP1 is differentially expressed in patient samples. We hope our findings help expand the characterization of molecular profiles in ALL settings and guide future investigations into novel biomarker detection and pharmacological choices in clinical practice.

5.
Int J Mol Sci ; 24(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38139046

RESUMO

Cognitive abilities tend to decline with aging, with variation between individuals, and many studies seek to identify genetic biomarkers that more accurately anticipate risks related to pathological aging. We investigated the influence of BDNF, NTRK2, and FNDC5 single nucleotide polymorphisms (SNPs) on the cognitive performance of young and older adults with contrasting educational backgrounds. We addressed three questions: (1) Is education associated with reduced age-related cognitive decline? (2) Does the presence of SNPs explain the variation in cognitive performance observed late in life? (3) Is education differentially associated with cognition based on the presence of BDNF, NTRK2, or FNDC5 polymorphisms? We measured the cognitive functions of young and older participants, with lower and higher education, using specific and sensitive tests of the Cambridge Automated Neuropsychological Test Assessment Battery. A three-way ANOVA revealed that SNPs were associated with differential performances in executive functions, episodic memory, sustained attention, mental and motor response speed, and visual recognition memory and that higher educational levels improved the affected cognitive functions. The results revealed that distinct SNPs affect cognition late in life differentially, suggesting their utility as potential biomarkers and emphasizing the importance of cognitive stimulation that advanced education early in life provides.


Assuntos
Disfunção Cognitiva , Memória Episódica , Humanos , Idoso , Fator Neurotrófico Derivado do Encéfalo/genética , Disfunção Cognitiva/genética , Cognição/fisiologia , Polimorfismo de Nucleotídeo Único , Fibronectinas/genética , Biomarcadores , Testes Neuropsicológicos
6.
Asian Pac J Cancer Prev ; 24(7): 2217-2223, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505750

RESUMO

OBJECTIVE: Perform a systematic literature review on SNORA42 in carcinogenesis in order to elucidate its importance, its potential use as a biomarker and as a therapeutic target. METHODS: Using PubMed, SciELO and Science Direct databases as search means, articles that are in line with the scope of the study, written in English, that were published between 2012 and 2022, were selected using the following keywords: "small nucleolar RNA 42", "snoRNA 42" and "SNORA42", as well as searches for the synonyms of this snoRNA (SNORA80E, box H/ACA 42 and ACA42). RESULT: From a total of 131 studies, seven were selected, in which it was possible to identify that SNORA42 interferes in several biological processes, such as proliferation, migration, invasion, metastasis, apoptosis, and signaling pathways. Among the signaling pathways, the p53 and NF-KappaB pathways stand out. Moreover, it is a potential biomarker for diagnosis, prognosis, and treatment of cancer. CONCLUSION: The summary of the main information about SNORA42 in the process of carcinogenesis and cancer progression shows that the use of this snoRNA is ideal for future applications in the field of oncology, in which it can be used as a biomarker and therapeutic target. Thus, it is of fundamental importance to carry out new studies to consolidate the applicability of this molecule.


Assuntos
Carcinogênese , RNA Nucleolar Pequeno , Humanos , RNA Nucleolar Pequeno/genética , RNA Nucleolar Pequeno/metabolismo , Prognóstico , Apoptose
7.
Molecules ; 28(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37513459

RESUMO

Gastric cancer is one of the most frequent types of neoplasms worldwide, usually presenting as aggressive and difficult-to-manage tumors. The search for new structures with anticancer potential encompasses a vast research field in which natural products arise as promising alternatives. In this scenario, piperine, an alkaloid of the Piper species, has received attention due to its biological activity, including anticancer attributes. The present work proposes three heating-independent, reliable, low-cost, and selective methods for obtaining piperine from Piper nigrum L. (Black pepper). Electronic (SEM) and optical microscopies, X-ray diffraction, nuclear magnetic resonance spectroscopies (13C and 1H NMR), and optical spectroscopies (UV-Vis, photoluminescence, and FTIR) confirm the obtention of piperine crystals. The MTT assay reveals that the piperine samples exhibit good cytotoxic activity against primary and metastasis models of gastric cancer cell lines from the Brazilian Amazon. The samples showed selective cytotoxicity on the evaluated models, revealing higher effectiveness in cells bearing a higher degree of aggressiveness. Moreover, the investigated piperine crystals demonstrated the ability to act as a good cytotoxicity enhancer when combined with traditional chemotherapeutics (5-FU and GEM), allowing the drugs to achieve the same cytotoxic effect in cells employing lower concentrations. These results establish piperine as a promising molecule for therapy investigations in aggressive gastric cancer, both in its isolated form or as a bioenhancer.


Assuntos
Alcaloides , Antineoplásicos , Piper nigrum , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Alcaloides/química , Benzodioxóis/química , Piperidinas/química , Alcamidas Poli-Insaturadas/química , Piper nigrum/química , Antineoplásicos/farmacologia
8.
Biomedicines ; 11(4)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37189716

RESUMO

Acute myeloid leukemia (AML) is a hematologic malignancy that occurs due to alterations such as genetic mutations, chromosomal translocations, or changes in molecular levels. These alterations can accumulate in stem cells and hematopoietic progenitors, leading to the development of AML, which has a prevalence of 80% of acute leukemias in the adult population. Recurrent cytogenetic abnormalities, in addition to mediating leukemogenesis onset, participate in its evolution and can be used as established diagnostic and prognostic markers. Most of these mutations confer resistance to the traditionally used treatments and, therefore, the aberrant protein products are also considered therapeutic targets. The surface antigens of a cell are characterized through immunophenotyping, which has the ability to identify and differentiate the degrees of maturation and the lineage of the target cell, whether benign or malignant. With this, we seek to establish a relationship according to the molecular aberrations and immunophenotypic alterations that cells with AML present.

9.
Cancers (Basel) ; 14(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36551612

RESUMO

Hereditary gastric cancers (HGCs) are supposed to be rare and difficult to identify. Nonetheless, many cases of young patients with gastric cancer (GC) fulfill the clinical criteria for considering this diagnosis but do not present the defined pathogenic mutations necessary to meet a formal diagnosis of HGC. Moreover, GC in young people is a challenging medical situation due to the usual aggressiveness of such cases and the potential risk for their relatives when related to a germline variant. Aiming to identify additional germline alterations that might contribute to the early onset of GC, a complete exome sequence of blood samples from 95 GC patients under 50 and 94 blood samples from non-cancer patients was performed and compared in this study. The number of identified germline mutations in GC patients was found to be much higher than that from individuals without a cancer diagnosis. Specifically, the number of high functional impact mutations, including those affecting genes involved in medical diseases, cancer hallmark genes, and DNA replication and repair processes, was much higher, strengthening the hypothesis of the potential causal role of such mutations in hereditary cancers. Conversely, classically related HGC mutations were not found and the number of mutations in genes in the CDH1 pathway was not found to be relevant among the young GC patients, reinforcing the hypothesis that existing alternative germline contributions favor the early onset of GC. The LILRB1 gene variants, absent in the world's cancer datasets but present in high frequencies among the studied GC patients, may represent essential cancer variants specific to the Amerindian ancestry's contributions. Identifying non-reported GC variants, potentially originating from under-studied populations, may pave the way for additional discoveries and translations to clinical interventions for GC management. The newly proposed approaches may reduce the discrepancy between clinically suspected and molecularly proven hereditary GC and shed light on similar inconsistencies among other cancer types. Additionally, the results of this study may support the development of new blood tests for evaluating cancer risk that can be used in clinical practice, helping physicians make decisions about strategies for surveillance and risk-reduction interventions.

10.
Curr Issues Mol Biol ; 44(11): 5498-5515, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36354684

RESUMO

The WD repeat containing antisense to TP53 (WRAP53) gene codifies an antisense transcript for tumor protein p53 (TP53), stabilization (WRAP53α), and a functional protein (WRAP53ß, WDR79, or TCAB1). The WRAP53ß protein functions as a scaffolding protein that is important for telomerase localization, telomere assembly, Cajal body integrity, and DNA double-strand break repair. WRAP53ß is one of many proteins known for containing WD40 domains, which are responsible for mediating a variety of cell interactions. Currently, WRAP53 overexpression is considered a biomarker for a diverse subset of cancer types, and in this study, we describe what is known about WRAP53ß's multiple interactions in cell protein trafficking, Cajal body formation, and DNA double-strand break repair and its current perspectives as a biomarker for cancer.

11.
Genes (Basel) ; 13(11)2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36421821

RESUMO

The COVID-19 pandemic initiated a race to determine the best measures to control the disease and to save as many people as possible. Efforts to implement social distancing, the use of masks, and massive vaccination programs turned out to be essential in reducing the devastating effects of the pandemic. Nevertheless, the high mutation rates of SARS-CoV-2 challenge the vaccination strategy and maintain the threat of new outbreaks due to the risk of infection surges and even lethal variations able to resist the effects of vaccines and upset the balance. Most of the new therapies tested against SARS-CoV-2 came from already available formulations developed to treat other diseases, so they were not specifically developed for SARS-CoV-2. In parallel, the knowledge produced regarding the molecular mechanisms involved in this disease was vast due to massive efforts worldwide. Taking advantage of such a vast molecular understanding of virus genomes and disease mechanisms, a targeted molecular therapy based on siRNA specifically developed to reach exclusive SARS-CoV-2 genomic sequences was tested in a non-transformed human cell model. Since coronavirus can escape from siRNA by producing siRNA inhibitors, a complex strategy to simultaneously strike both the viral infectious mechanism and the capability of evading siRNA therapy was developed. The combined administration of the chosen produced siRNA proved to be highly effective in successfully reducing viral load and keeping virus replication under control, even after many days of treatment, unlike the combinations of siRNAs lacking this anti-anti-siRNA capability. Additionally, the developed therapy did not harm the normal cells, which was demonstrated because, instead of testing the siRNA in nonhuman cells or in transformed human cells, a non-transformed human thyroid cell was specifically chosen for the experiment. The proposed siRNA combination could reduce the viral load and allow the cellular recovery, presenting a potential innovation for consideration as an additional strategy to counter or cope COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , Replicação Viral/genética , Genoma Viral , RNA Interferente Pequeno/genética
12.
Oncotarget ; 13: 1246-1257, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36395362

RESUMO

INTRODUCTION: Cancer research has significantly improved in recent years, primarily due to next-generation sequencing (NGS) technology. Consequently, an enormous amount of genomic and transcriptomic data has been generated. In most cases, the data needed for research goals are used, and unwanted reads are discarded. However, these eliminated data contain relevant information. Aiming to test this hypothesis, genomic and transcriptomic data were acquired from public datasets. MATERIALS AND METHODS: Metagenomic tools were used to explore genomic cancer data; additional annotations were used to explore differentially expressed ncRNAs from miRNA experiments, and variants in adjacent to tumor samples from RNA-seq experiments were also investigated. RESULTS: In all analyses, new data were obtained: from DNA-seq data, microbiome taxonomies were characterized with a similar performance of dedicated metagenomic research; from miRNA-seq data, additional differentially expressed sncRNAs were found; and in tumor and adjacent to tumor tissue data, somatic variants were found. CONCLUSIONS: These findings indicate that unexplored data from NGS experiments could help elucidate carcinogenesis and discover putative biomarkers with clinical applications. Further investigations should be considered for experimental design, providing opportunities to optimize data, saving time and resources while granting access to multiple genomic perspectives from the same sample and experimental run.


Assuntos
MicroRNAs , Neoplasias , Pequeno RNA não Traduzido , Humanos , Software , Sequenciamento de Nucleotídeos em Larga Escala , Genômica , MicroRNAs/genética , Neoplasias/genética
13.
BMC Cancer ; 22(1): 1063, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243680

RESUMO

BACKGROUND: Although penile cancer (PC) is uncommon in developed countries, it is widespread in developing countries. The state of Maranhão (Northeast, Brazil) has the highest global incidence recorded for PC, and, despite its socioeconomic vulnerability, it has been attributed to human papillomavirus (HPV) infection. This study aimed to determine the histopathological features, the prevalence of HPV infection, and the immunohistochemical profile of PC in Maranhão. METHODS: A retrospective cohort of 200 PC cases were evaluated. HPV detection was performed using nested-PCR followed by direct sequencing for genotyping. Immunohistochemistry (IHC) was performed using monoclonal antibodies anti-p16INK4a, p53, and ki-67. RESULTS: Our data revealed a delay of 17 months in diagnosis, a high rate of penile amputation (96.5%), and HPV infection (80.5%) in patients from Maranhão (Molecular detection). We demonstrated the high rate of HPV in PC also by histopathological and IHC analysis. Most patients presented koilocytosis (75.5%), which was associated with those reporting more than 10 different sexual partners during their lifetime (p = 0.001). IHC revealed frequent p16INK4a overexpression (26.0%) associated with basaloid (p < 0.001) and high-grade tumors (p = 0.008). Interestingly, p16 appears not to be a better prognostic factor in our disease-free survival analysis, as previously reported. We also demonstrated high ki-67 and p53 expression in a subset of cases, which was related to worse prognostic factors such as high-grade tumors, angiolymphatic and perineural invasion, and lymph node metastasis. We found a significant impact of high ki-67 (p = 0.002, log-rank) and p53 (p = 0.032, log-rank) expression on decreasing patients' survival, as well as grade, pT, stage, pattern, and depth of invasion (p < 0.05, log-rank). CONCLUSIONS: Our data reaffirmed the high incidence of HPV infection in PC cases from Maranhão and offer new insights into potential factors that may contribute to the high PC incidence in the region. We highlighted the possible association of HPV with worse clinical prognosis factors, differently from what was observed in other regions. Furthermore, our IHC analysis reinforces p16, ki-67, and p53 expression as important diagnosis and/or prognosis biomarkers, potentially used in the clinical setting in emerging countries such as Brazil.


Assuntos
Infecções por Papillomavirus , Neoplasias Penianas , Anticorpos Monoclonais/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Humanos , Incidência , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Papillomaviridae/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/patologia , Prognóstico , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética
14.
Pharmaceutics ; 14(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36145532

RESUMO

Multiple myeloma (MM) is a blood cell neoplasm characterized by excessive production of malignant monoclonal plasma cells (activated B lymphocytes) by the bone marrow, which end up synthesizing antibodies or antibody fragments, called M proteins, in excess. The accumulation of this production, both cells themselves and of the immunoglobulins, causes a series of problems for the patient, of a systemic and local nature, such as blood hyperviscosity, renal failure, anemia, bone lesions, and infections due to compromised immunity. MM is the third most common hematological neoplasm, constituting 1% of all cancer cases, and is a disease that is difficult to treat, still being considered an incurable disease. The treatments currently available cannot cure the patient, but only extend their lifespan, and the main and most effective alternative is autologous hematopoietic stem cell transplantation, but not every patient is eligible, often due to age and pre-existing comorbidities. In this context, the search for new therapies that can bring better results to patients is of utmost importance. Protein tyrosine kinases (PTKs) are involved in several biological processes, such as cell growth regulation and proliferation, thus, mutations that affect their functionality can have a great impact on crucial molecular pathways in the cells, leading to tumorigenesis. In the past couple of decades, the use of small-molecule inhibitors, which include tyrosine kinase inhibitors (TKIs), has been a hallmark in the treatment of hematological malignancies, and MM patients may also benefit from TKI-based treatment strategies. In this review, we seek to understand the applicability of TKIs used in MM clinical trials in the last 10 years.

15.
Int J Mol Sci ; 23(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897788

RESUMO

The circadian clock (CC) is a daily system that regulates the oscillations of physiological processes and can respond to the external environment in order to maintain internal homeostasis. For the functioning of the CC, the clock genes (CG) act in different metabolic pathways through the clock-controlled genes (CCG), providing cellular regulation. The CC's interruption can result in the development of different diseases, such as neurodegenerative and metabolic disorders, as well as cancer. Leukemias correspond to a group of malignancies of the blood and bone marrow that occur when alterations in normal cellular regulatory processes cause the uncontrolled proliferation of hematopoietic stem cells. This review aimed to associate a deregulated CC with the manifestation of leukemia, looking for possible pathways involving CG and their possible role as leukemic biomarkers.


Assuntos
Transtornos Cronobiológicos , Relógios Circadianos , Leucemia , Neoplasias , Biomarcadores , Relógios Circadianos/genética , Ritmo Circadiano/genética , Humanos , Leucemia/genética
16.
Front Genet ; 13: 875939, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812732

RESUMO

Cancer development by the human papillomavirus (HPV) infection can occur through the canonical HPV/p53/RB1 pathway mediated by the E2/E6/E7 viral oncoproteins. During the transformation process, HPV inserts its genetic material into host Integration Sites (IS), affecting coding genes and miRNAs. In penile cancer (PeCa) there is limited data on the miRNAs that regulate mRNA targets associated with HPV, such as the TP53 and RB1 genes. Considering the high frequency of HPV infection in PeCa patients in Northeast Brazil, global miRNA expression profiling was performed in high-risk HPV-associated PeCa that presented with TP53 and RB1 mRNA downregulated expression. The miRNA expression profile of 22 PeCa tissue samples and five non-tumor penile tissues showed 507 differentially expressed miRNAs: 494 downregulated and 13 upregulated (let-7a-5p, miR-130a-3p, miR-142-3p, miR-15b-5p miR-16-5p, miR-200c-3p, miR-205-5p, miR-21-5p, miR-223-3p, miR-22-3p, miR-25-3p, miR-31-5p and miR-93-5p), of which 11 were identified to be in HPV16-IS and targeting TP53 and RB1 genes. One hundred and thirty-one and 490 miRNA binding sites were observed for TP53 and RB1, respectively, most of which were in seedless regions. These findings suggest that up-regulation of miRNA expression can directly repress TP53 and RB1 expression by their binding sites in the non-canonical seedless regions.

17.
Front Oncol ; 12: 931050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814466

RESUMO

Hematopoietic stem cells (HSCs) are known for their ability to proliferate and self-renew, thus being responsible for sustaining the hematopoietic system and residing in the bone marrow (BM). Leukemic stem cells (LSCs) are recognized by their stemness features such as drug resistance, self-renewal, and undifferentiated state. LSCs are also present in BM, being found in only 0.1%, approximately. This makes their identification and even their differentiation difficult since, despite the mutations, they are cells that still have many similarities with HSCs. Although the common characteristics, LSCs are heterogeneous cells and have different phenotypic characteristics, genetic mutations, and metabolic alterations. This whole set of alterations enables the cell to initiate the process of carcinogenesis, in addition to conferring drug resistance and providing relapses. The study of LSCs has been evolving and its application can help patients, where through its count as a biomarker, it can indicate a prognostic factor and reveal treatment results. The selection of a target to LSC therapy is fundamental. Ideally, the target chosen should be highly expressed by LSCs, highly selective, absence of expression on other cells, in particular HSC, and preferentially expressed by high numbers of patients. In view of the large number of similarities between LSCs and HSCs, it is not surprising that current treatment approaches are limited. In this mini review we seek to describe the immunophenotypic characteristics and mechanisms of resistance presented by LSCs, also approaching possible alternatives for the treatment of patients.

18.
Front Oncol ; 12: 812008, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651809

RESUMO

Penile cancer (PC) still presents a health threat for developing countries, in particular Brazil. Despite this, little progress has been made on the study of markers, including molecular ones, that can aid in the correct management of the patient, especially concerning lymphadenectomy. As in other neoplasms, non-coding RNAs (ncRNAs) have been investigated for penile cancer, with emphasis on microRNAs, piRNAs (PIWI-interacting small RNAs), and long non-coding RNAs (LncRNAs). In this context, this review aims to assemble the available knowledge on non-coding RNA linked in PC, contributing to our understanding of the penile carcinogenesis process and addressing their clinical relevance. ncRNAs are part of the novel generation of biomarkers, with high potential for diagnosis and prognosis, orientating the type of treatment. Furthermore, its versatility regarding the use of paraffin samples makes it possible to carry out retrospective studies.

19.
Curr Issues Mol Biol ; 44(2): 942-951, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35723347

RESUMO

piRNAs are a class of noncoding RNAs that perform functions in epigenetic regulation and silencing of transposable elements, a mechanism conserved among most mammals. At present, there are more than 30,000 known piRNAs in humans, of which more than 80% are derived from intergenic regions, and approximately 20% are derived from the introns and exons of pre-mRNAs. It was observed that the expression of the piRNA profile is specific in several organs, suggesting that they play functional roles in different tissues. In addition, some studies suggest that changes in regions that encode piRNAs may have an impact on their function. To evaluate the conservation of these regions and explore the existence of a seed region, SNP and INDEL variant rates were investigated in several genomic regions and compared to piRNA region variant rates. Thus, data analysis, data collection, cleaning, treatment, and exploration were implemented using the R programming language with the help of the RStudio platform. We found that piRNA regions are highly conserved after considering INDELs and do not seem to present an identifiable seed region after considering SNPs and INDEL variants. These findings may contribute to future studies attempting to determine how polymorphisms in piRNA regions can impact diseases.

20.
Int J Mol Sci ; 23(10)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35628297

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) was identified as the first pathogenic human retrovirus and is estimated to infect 5 to 10 million individuals worldwide. Unlike other retroviruses, there is no effective therapy to prevent the onset of the most alarming diseases caused by HTLV-1, and the more severe cases manifest as the malignant phenotype of adult T cell leukemia (ATL). MicroRNA (miRNA) dysfunction is a common feature of leukemogenesis, and it is no different in ATL cases. Therefore, we sought to analyze studies that reported deregulated miRNA expression in HTLV-1 infected cells and patients' samples to understand how this deregulation could induce malignancy. Through in silico analysis, we identified 12 miRNAs that stood out in the prediction of targets, and we performed functional annotation of the genes linked to these 12 miRNAs that appeared to have a major biological interaction. A total of 90 genes were enriched in 14 KEGG pathways with significant values, including TP53, WNT, MAPK, TGF-ß, and Ras signaling pathways. These miRNAs and gene interactions are discussed in further detail for elucidation of how they may act as probable drivers for ATL onset, and while our data provide solid starting points for comprehension of miRNAs' roles in HTLV-1 infection, continuous effort in oncologic research is still needed to improve our understanding of HTLV-1 induced leukemia.


Assuntos
Infecções por HTLV-I , Leucemia-Linfoma de Células T do Adulto , MicroRNAs , Biologia Computacional , Infecções por HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/virologia , MicroRNAs/genética
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