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BACKGROUND: Colorectal cancer (CRC) is among the deadliest cancers, wherein early dissemination of tumor cells, and consequently, metastasis formation, are the main causes of mortality and poor prognosis. Cofilin-1 (CFL-1) and its modulators, LIMK1/SSH1, play key roles in mediating the invasiveness by driving actin cytoskeleton reorganization in various cancer types. However, their clinical significance and prognostic value in CRC has not been fully explored. Here, we evaluated the clinical contribution of these actin regulators according to TNM and consensus molecular subtypes (CMSs) classification. METHODS: CFL-1, LIMK1 and SSH1 mRNA/protein levels were assessed by real-time PCR and immunohistochemical analyses using normal adjacent and tumor tissues obtained from a clinical cohort of CRC patients. The expression levels of these proteins were associated with clinicopathological features by using the chi square test. In addition, using RNA-Seq data of CRC patients from The Cancer Genome Atlas (TCGA) database, we determine how these actin regulators are expressed and distributed according to TNM and CMSs classification. Based on gene expression profiling, Kaplan-Meier survival analysis was used to evaluated overall survival. RESULTS: Bioinformatic analysis revealed that LIMK1 expression was upregulated in all tumor stages. Patients with high levels of LIMK1 demonstrated significantly lower overall survival rates and exhibited greater lymph node metastatic potential in a clinical cohort. In contrast, CFL-1 and SSH1 have expression downregulated in all tumor stages. However, immunohistochemical analyses showed that patients with high protein levels of CFL-1 and SSH1 exhibited greater lymph node metastatic potential and greater depth of local invasion. In addition, using the CMSs classification to evaluate different biological phenotypes of CRC, we observed that LIMK1 and SSH1 genes are upregulated in immune (CMS1) and mesenchymal (CMS4) subtypes. However, patients with high levels of LIMK1 also demonstrated significantly lower overall survival rates in canonical (CMS2), and metabolic (CMS3) subtypes. CONCLUSIONS: We demonstrated that CFL-1 and its modulators, LIMK1/SSH1, are differentially expressed and associated with lymph node metastasis in CRC. Finally, this expression profile may be useful to predict patients with aggressive signatures, particularly, the immune and mesenchymal subtypes of CRC.
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BACKGROUND: Interaction between malignant cells and immune cells that reside within the tumor microenvironment (TME) modulate different aspects of tumor development and progression. Recent works showed the importance of miRNA-containing extracellular vesicles in this crosstalk. METHODS: Interested in understanding the interplay between melanoma and immune-related TME cells, we characterized the TCGA's metastatic melanoma samples according to their tumor microenvironment profiles, HLA-I neoepitopes, transcriptome profile and classified them into three groups. Moreover, we combined our results with melanoma single-cell gene expression and public miRNA data to better characterize the regulatory network of circulating miRNAs and their targets related to immune evasion and microenvironment response. RESULTS: The group associated with a worse prognosis showed phenotypic characteristics that favor immune evasion, including a strong signature of suppressor cells and less stable neoantigen:HLA-I complexes. Conversely, the group with better prognosis was marked by enrichment in lymphocyte and MHC signatures. By analyzing publicly available melanoma single-cell RNA and microvesicle microRNAs sequencing data we identified circulating microRNAs potentially involved in the crosstalk between tumor and TME cells. Candidate miRNA/target gene pairs with previously reported roles in tumor progression and immune escape mechanisms were further investigated and demonstrated to impact patient's overall survival not only in melanoma but across different tumor types. CONCLUSION: Our results underscore the impact of tumor-microenvironment interactions on disease outcomes and reveal potential non-invasive biomarkers of prognosis and treatment response.
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Melanoma , MicroRNAs , Humanos , Melanoma/genética , MicroRNAs/genética , Prognóstico , Transcriptoma , Microambiente TumoralRESUMO
The tumor suppressor gene RB1 (Human Retinoblastoma Susceptibility Gene) plays a prominent role in normal development, gene transcription, DNA replication, repair, and mitosis. Its complete biallelic dysfunction in retinoblasts is the main cause of retinoblastoma in the human. Although this gene has been evolutionary conserved, comparisons between the reference and human RB1 coding region with its counterparts in 19 non-human primates showed 359 sites where nucleotide replacements took place during the radiation of these species. These resulted in missense substitutions in 97 codons, 91 of which by amino acids with radically different physicochemical properties. Several in frame deletions and two insertions were also observed in the N-terminal region of the pRB protein where the highest number of amino acid substitutions and radical amino changes were found. Fifty-six codons were inferred to be under negative selection and five under positive selection. Differences in codon usage showed evident phylogenetic signals, with hominids generally presenting higher indices of codon bias than other catarrhines. The lineage leading to platyrrhines and, within platyrrhines, the lineage leading to Saimiri boliviensis showed a high rate of nucleotide substitutions and amino acids. Finally, several RB1 alterations associated to retinoblastoma in the human were present in several non-human primates without an apparent pathological effect.
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Evolução Molecular , Filogenia , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Animais , Humanos , Primatas/genética , Retinoblastoma/patologiaRESUMO
To decrypt the regulatory code of the genome, sequence elements must be defined that determine the kinetics of RNA metabolism and thus gene expression. Here, we attempt such decryption in an eukaryotic model organism, the fission yeast S. pombe. We first derive an improved genome annotation that redefines borders of 36% of expressed mRNAs and adds 487 non-coding RNAs (ncRNAs). We then combine RNA labeling in vivo with mathematical modeling to obtain rates of RNA synthesis and degradation for 5,484 expressed RNAs and splicing rates for 4,958 introns. We identify functional sequence elements in DNA and RNA that control RNA metabolic rates and quantify the contributions of individual nucleotides to RNA synthesis, splicing, and degradation. Our approach reveals distinct kinetics of mRNA and ncRNA metabolism, separates antisense regulation by transcription interference from RNA interference, and provides a general tool for studying the regulatory code of genomes.
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Regulação Fúngica da Expressão Gênica , Genoma Fúngico , RNA Fúngico/genética , RNA Mensageiro/genética , Schizosaccharomyces/genética , Íntrons , Interferência de RNA , Splicing de RNA , RNA Antissenso/genética , Análise de Sequência de RNA , Transcrição GênicaRESUMO
INTRODUCTION: Senescent cells contribute to age-related tissue deterioration, including the skin, which plays important roles in overall health and social interactions. This study aimed to assess the effects of the senotherapeutic peptide, OS-01 (a.k.a. Pep 14), on skin. METHODS: A 12-week split-face, double-blinded, vehicle-controlled study involving 22 participants was conducted. The OS-01-containing formulation was applied to one side of the face, while the other side received an identical control formulation lacking the peptide. Skin characteristics were assessed using instrumental measurements, expert clinical grading, and subjective questionnaires. RESULTS: Results showed that the OS-01 formulation significantly improved one aspect of skin barrier function, as evidenced by reduced trans-epidermal water loss compared to both baseline and vehicle control. Expert grading and Antera 3D image analysis revealed a reduction in wrinkle appearance and indentation in the periorbital area, and improved skin texture and radiance on both sides of the face, with the OS-01-containing formulation demonstrating superior results. Participants also perceived improvements in skin hydration, smoothness, radiance, and overall appearance. CONCLUSION: The findings suggest that the OS-01 formulation promotes skin health by strengthening the skin barrier, protecting against dehydration, reducing the appearance of wrinkles, and improving skin texture and radiance. These effects are likely attributed to the senotherapeutic properties of OS-01 in reducing cellular senescence and its associated detrimental effects.
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Rejuvenescimento , Envelhecimento da Pele , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Método Duplo-Cego , Pessoa de Meia-Idade , Feminino , Adulto , Perda Insensível de Água/efeitos dos fármacos , Face , Pele/efeitos dos fármacos , Pele/patologia , Masculino , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Administração Cutânea , IdosoRESUMO
Inflammation contributes to the onset and exacerbation of numerous age-related diseases, often manifesting as a chronic condition during aging. Given that cellular senescence fosters local and systemic inflammation, senotherapeutic interventions could potentially aid in managing or even reducing inflammation. Here, we investigated the immunomodulatory effects of the senotherapeutic Peptide 14 (Pep 14) in human peripheral blood mononuclear cells (PBMCs), monocytes, and macrophages. We found that, despite failing to significantly influence T cell activation and proliferation, the peptide promoted a Th2/Treg gene expression and cytokine signature in PBMCs, characterized by increased expression of the transcription factors GATA3 and FOXP3, as well as the cytokines IL-4 and IL-10. These observations were partially confirmed through ELISA, in which we observed increased IL-10 release by resting and PHA-stimulated PBMCs. In monocytes from the U-937 cell line, Pep 14 induced apoptosis in lipopolysaccharide (LPS)-stimulated cells and upregulated IL-10 expression. Furthermore, Pep 14 prevented LPS-induced activation and promoted an M2-like polarization in U-937-derived macrophages, evidenced by decreased expression of M1 markers and increased expression of M2 markers. We also showed that the conditioned media from Pep 14-treated macrophages enhanced fibroblast migration, indicative of a functional M2 phenotype. Taken together, our findings suggest that Pep 14 modulates immune cell function towards an anti-inflammatory and regenerative phenotype, highlighting its potential as a therapeutic intervention to alleviate immunosenescence-associated dysregulation.
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Macrófagos , Monócitos , Células Th1 , Humanos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Peptídeos/farmacologia , Lipopolissacarídeos/farmacologia , Citocinas/metabolismo , Interleucina-10/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacosRESUMO
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.
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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/genéticaRESUMO
Tumor-associated myeloid-derived cells (MDCs) significantly impact cancer prognosis and treatment responses due to their remarkable plasticity and tumorigenic behaviors. Here, we integrate single-cell RNA-sequencing data from different cancer types, identifying 29 MDC subpopulations within the tumor microenvironment. Our analysis reveals abnormally expanded MDC subpopulations across various tumors and distinguishes cell states that have often been grouped together, such as TREM2+ and FOLR2+ subpopulations. Using deconvolution approaches, we identify five subpopulations as independent prognostic markers, including states co-expressing TREM2 and PD-1, and FOLR2 and PDL-2. Additionally, TREM2 alone does not reliably predict cancer prognosis, as other TREM2+ macrophages show varied associations with prognosis depending on local cues. Validation in independent cohorts confirms that FOLR2-expressing macrophages correlate with poor clinical outcomes in ovarian and triple-negative breast cancers. This comprehensive MDC atlas offers valuable insights and a foundation for futher analyses, advancing strategies for treating solid cancers.
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Glicoproteínas de Membrana , Células Mieloides , Neoplasias , Receptores Imunológicos , Análise de Célula Única , Microambiente Tumoral , Humanos , Análise de Célula Única/métodos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Células Mieloides/metabolismo , Células Mieloides/patologia , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Prognóstico , Neoplasias/genética , Neoplasias/patologia , Neoplasias/metabolismo , Feminino , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/genética , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genéticaRESUMO
Castor bean (Ricinus communis L.) can withstand long periods of water deficit and high temperatures, and therefore has been recognized as a drought-resistant plant species, allowing the study of gene networks involved in drought response and tolerance. The identification of genes networks related to drought response in this plant may yield important information in the characterization of molecular mechanisms correlating changes in the gene expression with the physiological adaptation processes. In this context, gene families related to abscisic acid (ABA) signaling play a crucial role in developmental and environmental adaptation processes of plants to drought stress. However, the families that function as the core components of ABA signaling, as well as genes networks related to drought response, are not well understood in castor bean. In this study 7 RcPYL, 63 RcPP2C, and 6 RcSnRK2 genes were identified in castor bean genome, which was further supported by chromosomal distribution, gene structure, evolutionary relationships, and conserved motif analyses. The castor bean general expression profile was investigated by RNAseq in root and leaf tissues in response to drought stress. These analyses allowed the identification of genes differentially expressed, including genes from the ABA signaling core, genes related to photosynthesis, cell wall, energy transduction, antioxidant response, and transcription factors. These analyses provide new insights into the core components of ABA signaling in castor bean, allow the identification of several molecular responses associated with the high physiological adaptation of castor bean to drought stress, and contribute to the identification of candidate genes for genetic improvement.
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Ricinus communis , Ricinus communis/genética , Ricinus communis/metabolismo , Ricinus/genética , Ricinus/metabolismo , Redes Reguladoras de Genes , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Transcriptoma , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismoRESUMO
Cellular senescence is known to play a role in age-related skin function deterioration which potentially influences longevity. Here, a two-step phenotypic screening was performed to identify senotherapeutic peptides, leading to the identification of Peptide (Pep) 14. Pep 14 effectively decreased human dermal fibroblast senescence burden induced by Hutchinson-Gilford Progeria Syndrome (HGPS), chronological aging, ultraviolet-B radiation (UVB), and etoposide treatment, without inducing significant toxicity. Pep 14 functions via modulation of PP2A, an understudied holoenzyme that promotes genomic stability and is involved in DNA repair and senescence pathways. At the single-cell level, Pep 14 modulates genes that prevent senescence progression by arresting the cell cycle and enhancing DNA repair, which consequently reduce the number of cells progressing to late senescence. When applied on aged ex vivo skin, Pep 14 promoted a healthy skin phenotype with structural and molecular resemblance to young ex vivo skin, decreased the expression of senescence markers, including SASP, and reduced the DNA methylation age. In summary, this work shows the safe reduction of the biological age of ex vivo human skins by a senomorphic peptide.
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Invariant natural killer T (iNKT) cells are a distinct population of lymphocytes characterized by their reactivity to glycolipids presented by CD1d. iNKT cells are found throughout the body, and little is known about their tissue-specific metabolic regulation. Here, we show that splenic and hepatic iNKT cells are metabolically comparable and rely on glycolytic metabolism to support their activation. Deletion of the pyruvate kinase M2 (Pkm2) gene in splenic and hepatic iNKT cells impairs their response to specific stimulation and their ability to mitigate acute liver injury. In contrast, adipose tissue (AT) iNKT cells exhibit a distinctive immunometabolic profile, with AMP-activated protein kinase (AMPK) being necessary for their function. AMPK deficiency impairs AT-iNKT physiology, blocking their capacity to maintain AT homeostasis and their ability to regulate AT inflammation during obesity. Our work deepens our understanding on the tissue-specific immunometabolic regulation of iNKT cells, which directly impacts the course of liver injury and obesity-induced inflammation.
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Proteínas Quinases Ativadas por AMP , Células T Matadoras Naturais , Inflamação , Fígado , Metaboloma , Obesidade , Animais , CamundongosRESUMO
SARS-CoV-2 variants of concern have emerged since the COVID-19 outburst, notably the lineages detected in the UK, South Africa, and Brazil. Their increased transmissibility and higher viral load put them in the spotlight. Much has been investigated on the ability of those new variants to evade antibody recognition. However, little attention has been given to pre-existing and induced SARS-CoV-2-specific CD8+ T cell responses by new lineages. In this work, we predicted SARS-CoV-2-specific CD8+ T cell epitopes from the main variants of concern and their potential to trigger or hinder CD8+ T cell response by using HLA binding and TCR reactivity in silico predictions. Also, we estimated the population's coverage for different lineages, which accounts for the ability to present a set of peptides based on the most frequent HLA alleles of a given population. We considered binding predictions to 110 ccClass I HLA alleles from 29 countries to investigate differences in the fraction of individuals expected to respond to a given epitope set from new and previous lineages. We observed a higher population coverage for the variant detected in the UK (B.1.1.7), and South Africa (B.1.351), as well as for the Brazilian P.1 lineage, but not P.2, compared to the reference lineage. Moreover, individual mutations such as Spike N501Y and Nucleocapsid D138Y were predicted to have an overall stronger affinity through HLA-I than the reference sequence while Spike E484K shows signs of evasion. In summary, we provided evidence for the existence of potentially immunogenic and conserved epitopes across new SARS-CoV-2 variants, but also mutant peptides exhibiting diminished or abolished HLA-I binding. It also highlights the augmented population coverage for three new lineages. Whether these changes imply more T cell reactivity or potential to evade from CD8+ T cell responses requires experimental verification.
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COVID-19 , SARS-CoV-2 , Linfócitos T CD8-Positivos , Epitopos de Linfócito T/genética , Humanos , Imunidade , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
The KMT2A (MLL) gene rearrangements (KMT2A-r) are associated with a diverse spectrum of acute leukemias. Although most KMT2A-r are restricted to nine partner genes, we have recently revealed that KMT2A-USP2 fusions are often missed during FISH screening of these genetic alterations. Therefore, complementary methods are important for appropriate detection of any KMT2A-r. Here we use a machine learning model to unravel the most appropriate markers for prediction of KMT2A-r in various types of acute leukemia. A Random Forest and LightGBM classifier was trained to predict KMT2A-r in patients with acute leukemia. Our results revealed a set of 20 genes capable of accurately estimating KMT2A-r. The SKIDA1 (AUC: 0.839; CI: 0.799-0.879) and LAMP5 (AUC: 0.746; CI: 0.685-0.806) overexpression were the better markers associated with KMT2A-r compared to CSPG4 (also named NG2; AUC: 0.722; CI: 0.659-0.784), regardless of the type of acute leukemia. Of importance, high expression levels of LAMP5 estimated the occurrence of all KMT2A-USP2 fusions. Also, we performed drug sensitivity analysis using IC50 data from 345 drugs available in the GDSC database to identify which ones could be used to treat KMT2A-r leukemia. We observed that KMT2A-r cell lines were more sensitive to 5-Fluorouracil (5FU), Gemcitabine (both antimetabolite chemotherapy drugs), WHI-P97 (JAK-3 inhibitor), Foretinib (MET/VEGFR inhibitor), SNX-2112 (Hsp90 inhibitor), AZD6482 (PI3Kß inhibitor), KU-60019 (ATM kinase inhibitor), and Pevonedistat (NEDD8-activating enzyme (NAE) inhibitor). Moreover, IC50 data from analyses of ex-vivo drug sensitivity to small-molecule inhibitors reveals that Foretinib is a promising drug option for AML patients carrying FLT3 activating mutations. Thus, we provide novel and accurate options for the diagnostic screening and therapy of KMT2A-r leukemia, regardless of leukemia subtype.
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To investigate similarities in the gene profile of Oral Lichen Planus and Oral Squamous Cell Carcinoma that may justify a carcinogenic potential, we analyzed the gene expression signatures of Oral Lichen Planus and Oral Squamous Cell Carcinoma in early and advanced stages. Based on gene expression data from public databases, we used a bioinformatics approach to compare expression profiles, estimate immune infiltrate composition, identify differentially and co-expressed genes, and propose putative therapeutic targets and associated drugs. Our results revealed gene expression patterns related to processes of keratinization, keratinocyte differentiation, cell proliferation and immune response in common between Oral Lichen Planus and early and advanced Oral Squamous Cell Carcinoma, with the cornified envelope formation and antigen processing cross-presentation pathways in common between Oral Lichen Planus and early Oral Squamous Cell Carcinoma. Together, these results reveal that key tumor suppressors and oncogenes such as PI3, SPRR1B and KRT17, as well as genes associated with different immune processes such as CXCL13, HIF1A and IL1B are dysregulated in OLP.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Líquen Plano Bucal , Neoplasias Bucais , Humanos , Neoplasias Bucais/genética , Líquen Plano Bucal/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço , Oncogenes , Carcinogênese/genéticaRESUMO
Senotherapeutic molecules decrease cellular senescence burden, constituting promising approaches to combat the accumulation of senescent cells observed in chronological aging and age-related diseases. Numerous molecules have displayed senotherapeutic potential, but toxicity has been frequently observed. Recently, a new senotherapeutic compound, Peptide 14, was developed to modulate cellular senescence in the skin. In order to assess the potential toxic and genotoxic effects of the peptide, we observed the viability of human primary dermal fibroblasts and epidermal keratinocytes with Peptide 14 treatment, and show that it is mostly non-toxic in concentrations up to 100 µM. Cancer lines were also used to investigate its potential of modulating proliferation. Different concentrations of the peptide promoted a discrete reduction in the proliferation of cancerous cells of the MeWo and HeLa lineages. In full-thickness human skin equivalents, topically formulated Peptide 14 also failed to exert any significant irritation, nor cellular toxicity when added to the culture media. Genotoxic assays including the Ames, micronucleus, and karyotyping tests also indicate the safety of the peptide. Finally, the irritative potential of the peptide was assessed in human subjects in a repeated insult patch test executed using 1 mM peptide. No visible skin reactions were observed in any of the 54 participants. Taken together, the present data support that Peptide 14 is a senotherapeutic molecule with a positive safety profile as tested with cruelty-free models, justifying further studies involving the peptide.
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Several studies have demonstrated the cost-effectiveness of genetic testing for surveillance and treatment of carriers of germline pathogenic variants associated with hereditary breast/ovarian cancer syndrome (HBOC). In Brazil, seventy percent of the population is assisted by the public Unified Health System (SUS), where genetic testing is still unavailable. And few studies were performed regarding the prevalence of HBOC pathogenic variants in this context. Here, we estimated the prevalence of germline pathogenic variants in BRCA1, BRCA2 and TP53 genes in Brazilian patients suspected of HBOC and referred to public healthcare service. Predictive power of risk prediction models for detecting mutation carriers was also evaluated. We found that 41 out of 257 tested patients (15.9%) were carriers of pathogenic variants in the analyzed genes. Most frequent pathogenic variant was the founder Brazilian mutation TP53 c.1010G > A (p.Arg337His), adding to the accumulated evidence that supports inclusion of TP53 in routine testing of Brazilian HBOC patients. Surprisingly, BRCA1 c.5266dupC (p.Gln1756fs), a frequently reported pathogenic variant in Brazilian HBOC patients, was not observed. Regarding the use of predictive models, we found that familial history of cancer might be used to improve selection or prioritization of patients for genetic testing, especially in a context of limited resources.
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Neoplasias da Mama , Síndromes Neoplásicas Hereditárias , Neoplasias Ovarianas , Feminino , Humanos , Brasil/epidemiologia , Prevalência , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/diagnóstico , Predisposição Genética para Doença , Proteína BRCA2/genética , Proteína BRCA1/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Carcinoma Epitelial do Ovário , Atenção à Saúde , Mutação em Linhagem Germinativa , Proteína Supressora de Tumor p53/genéticaRESUMO
[This corrects the article DOI: 10.3389/fonc.2022.904813.].
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Homologous recombination is a crucial pathway that is specialized in repairing double-strand breaks; thus, alterations in genes of this pathway may lead to loss of genomic stability and cell growth suppression. Pesticide exposure potentially increases cancer risk through several mechanisms, such as the genotoxicity caused by chronic exposure, leading to gene alteration. To analyze this hypothesis, we investigated if breast cancer patients exposed to pesticides present a different mutational pattern in genes related to homologous recombination (BRCA1, BRCA2, PALB2, and RAD51D) and damage-response (TP53) concerning unexposed patients. We performed multiplex PCR-based assays and next-generation sequencing (NGS) of all coding regions and flanking splicing sites of BRCA1, BRCA2, PALB2, TP53, and RAD51D in 158 unpaired tumor samples from breast cancer patients on MiSeq (Illumina) platform. We found that exposed patients had tumors with more pathogenic and likely pathogenic variants than unexposed patients (p = 0.017). In general, tumors that harbored a pathogenic or likely pathogenic variant had a higher mutational burden (p < 0.001). We also observed that breast cancer patients exposed to pesticides had a higher mutational burden when diagnosed before 50 years old (p = 0.00978) and/or when carrying BRCA1 (p = 0.0138), BRCA2 (p = 0.0366), and/or PALB2 (p = 0.00058) variants, a result not found in the unexposed group. Our results show that pesticide exposure impacts the tumor mutational landscape and could be associated with the carcinogenesis process, therapy response, and disease progression. Further studies should increase the observation period in exposed patients to better evaluate the impact of these findings.
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Melanoma is one of the most aggressive tumors, and its lethality is associated with the ability of malignant cells to migrate and invade surrounding tissues to colonize distant organs and to generate widespread metastasis. The serine/arginine protein kinases 1 and 2 (SRPK1 and SRPK2) are classically related to the control of pre-mRNA splicing through SR protein phosphorylation and have been found overexpressed in many types of cancer, including melanoma. Previously, we have demonstrated that the pharmacological inhibition of SRPKs impairs pulmonary colonization of metastatic melanoma in mice. As the used compounds could target at least both SRPK1 and SRPK2, here we sought to obtain additional clues regarding the involvement of these paralogs in melanoma progression. We analyzed single-cell RNA sequencing data of melanoma patient cohorts and found that SRPK2 expression in melanoma cells is associated with poor prognosis. Consistently, CRISPR-Cas9 genome targeting of SRPK2, but not SRPK1, impaired actin polymerization dynamics as well as the proliferative and invasive capacity of B16F10 cells in vitro. In further in vivo experiments, genetic targeting of SRPK2, but not SRPK1, reduced tumor progression in both subcutaneous and caudal vein melanoma induction models. Taken together, these findings suggest different functional roles for SRPK1/2 in metastatic melanoma and highlight the relevance of pursuing selective pharmacological inhibitors of SRPK2.
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Dietary restriction (DR) reduces adiposity and improves metabolism in patients with one or more symptoms of metabolic syndrome. Nonetheless, it remains elusive whether the benefits of DR in humans are mediated by calorie or nutrient restriction. This study was conducted to determine whether isocaloric dietary protein restriction is sufficient to confer the beneficial effects of dietary restriction in patients with metabolic syndrome. We performed a prospective, randomized controlled dietary intervention under constant nutritional and medical supervision. Twenty-one individuals diagnosed with metabolic syndrome were randomly assigned for caloric restriction (CR; n = 11, diet of 5941 ± 686 KJ per day) or isocaloric dietary protein restriction (PR; n = 10, diet of 8409 ± 2360 KJ per day) and followed for 27 days. Like CR, PR promoted weight loss due to a reduction in adiposity, which was associated with reductions in blood glucose, lipid levels, and blood pressure. More strikingly, both CR and PR improved insulin sensitivity by 62.3% and 93.2%, respectively, after treatment. Fecal microbiome diversity was not affected by the interventions. Adipose tissue bulk RNA-Seq data revealed minor changes elicited by the interventions. After PR, terms related to leukocyte proliferation were enriched among the upregulated genes. Protein restriction is sufficient to confer almost the same clinical outcomes as calorie restriction without the need for a reduction in calorie intake. The isocaloric characteristic of the PR intervention makes this approach a more attractive and less drastic dietary strategy in clinical settings and has more significant potential to be used as adjuvant therapy for people with metabolic syndrome.