RESUMO
R-loops cause genome instability, disrupting normal cellular functions. Histone acetylation, particularly by p300/CBP-associated factor (PCAF), is essential for maintaining genome stability and regulating cellular processes. Understanding how R-loop formation and resolution are regulated is important because dysregulation of these processes can lead to multiple diseases, including cancer. This study explores the role of PCAF in maintaining genome stability, specifically for R-loop resolution. We found that PCAF depletion promotes the generation of R-loop structures, especially during ongoing transcription, thereby compromising genome stability. Mechanistically, we found that PCAF facilitates histone H4K8 acetylation, leading to recruitment of the a double-strand break repair protein (MRE11) and exonuclease 1 (EXO1) to R-loop sites. These in turn recruit Fanconi anemia (FA) proteins, including FANCM and BLM, to resolve the R-loop structure. Our findings suggest that PCAF, histone acetylation, and FA proteins collaborate to resolve R-loops and ensure genome stability. This study therefore provides novel mechanistic insights into the dynamics of R-loops as well as the role of PCAF in preserving genome stability. These results may help develop therapeutic strategies to target diseases associated with genome instability.
R-loops are harmful DNA-RNA hybrid structures that cause genome instability, disrupting normal cell functions. This study explored the role of the protein PCAF in resolving R-loops to maintain genome stability. The researchers found that depleting PCAF leads to increased R-loop formation, especially during transcription, compromising the genome. Mechanistically, PCAF facilitates histone acetylation, recruiting proteins like MRE11, EXO1, FANCM and BLM to R-loop sites. These proteins collaborate to resolve R-loop structures. The findings suggest that PCAF, histone acetylation, and these repair proteins work together to untangle R-loops and preserve genome integrity. Understanding this process provides insights into R-loop dynamics and PCAF's role in genome maintenance, potentially leading to therapeutic strategies for diseases associated with genome instability, such as cancer.
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Instabilidade Genômica , Histonas , Estruturas R-Loop , Fatores de Transcrição de p300-CBP , Acetilação , Histonas/metabolismo , Histonas/genética , Fatores de Transcrição de p300-CBP/metabolismo , Fatores de Transcrição de p300-CBP/genética , Humanos , Exodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , Reparo do DNA , Enzimas Reparadoras do DNARESUMO
Background and Objectives: Despite high incidences of cognitive impairment with aging, evidence on the prevalence and the seriousness of drug-induced cognitive impairment is limited. This study aims to evaluate the prevalence and the severity of drug-induced cognitive impairment and to investigate the clinical predictors of increased hospitalization risk from serious drug-induced cognitive impairment. Materials and Methods: Adverse drug events (ADEs) regarding drug-induced cognitive impairment reported to the Korean Adverse Event Reporting System Database (KAERS DB) from January 2012 to December 2021 were included (KIDS KAERS DB 2212A0073). The association between the etiologic classes and the reporting serious adverse events (SAEs) was evaluated using disproportionality analysis, and the effect was estimated with reporting odds ratio (ROR). Clinical predictors associated with increased risk of hospitalization from SAEs were identified via multivariate logistic analysis, and the effect was estimated with odds ratio (OR). Results: The most etiologic medication class for drug-induced cognitive impairment ADEs was analgesics, followed by sedative-hypnotics. Anticancer (ROR 57.105, 95% CI 15.174-214.909) and anti-Parkinson agents (ROR 4.057, 95% CI 1.121-14.688) were more likely to report serious drug-induced cognitive impairments. Male sex (OR 19.540, 95% CI 2.440-156.647) and cancer diagnosis (OR 18.115, 95% CI 3.246-101.101) are the major clinical predictors for increased risk of hospitalizations due to serious drug-induced cognitive impairment. Conclusions: This study highlights the significant prevalence and severity of drug-induced cognitive impairment with cancer diagnosis and anticancer agents. However, further large-scaled studies are required because of the potential underreporting of drug-induced cognitive impairments in real practice settings, which is further contributed to by the complexity of multiple contributing factors such as comorbidities.
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Sistemas de Notificação de Reações Adversas a Medicamentos , Disfunção Cognitiva , Farmacovigilância , Humanos , Masculino , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/epidemiologia , Feminino , República da Coreia/epidemiologia , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso , Adulto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Prevalência , Hospitalização/estatística & dados numéricos , Adolescente , Idoso de 80 Anos ou maisRESUMO
Colorectal cancer (CRC) is one of the most common and deadly cancers in the world. However, no effective treatment for the disease has yet been found. For this reason, several studies are being carried out on the treatment of CRC. Currently, there is limited understanding of the role of CPNE7 (copine-7) in CRC progression and metastasis. The results of this study show that CPNE7 exerts an oncogenic effect in CRC. First, CPNE7 was shown to be significantly up-regulated in CRC patient tissues and CRC cell lines compared to normal tissues according to IHC staining, qRT-PCR, and western blotting. Next, this study used both systems of siRNA and shRNA to suppress CPNE7 gene expression to check the CPNE7 mechanism in CRC. The suppressed CPNE7 significantly inhibited the growth of CRC cells in in vitro experiments, including migration, invasion, and semisolid agar colony-forming assay. Moreover, the modified expression of CPNE7 led to a decrease in the levels of genes associated with epithelial-mesenchymal transition (EMT). The epithelial genes E-cadherin (CDH1) and Collagen A1 were upregulated, and the levels of mesenchymal genes such as N-cadherin (CDH2), ZEB1, ZEB2, and SNAIL (SNAL1) were downregulated after CPNE7 inhibition. This study suggests that CPNE7 may serve as a potential diagnostic biomarker for CRC patients.
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Neoplasias Colorretais , Transdução de Sinais , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica , RNA Interferente Pequeno/genéticaRESUMO
Interleukin-15 (IL-15) is a pleiotropic cytokine that plays pivotal roles in innate and adaptive immunity. It is also a promising cytokine for treating cancer. Despite growing interest in its use as an immunotherapeutic, its safety and immunological effects in dogs have not been reported. In this study, healthy dogs were given recombinant canine IL-15 (rcIL-15) intravenously at a daily dose of 20 µg/kg for 8 days and monitored for 32 days to determine the safety and immunological effects of rcIL-15. The repeated administration of rcIL-15 was well tolerated, did not cause any serious side effects, and promoted the selective proliferation and activation of canine anti-cancer effector cells, including CD3+CD8+ cytotoxic T lymphocytes, CD3+CD5dimCD21-, and non-B/non-T NK cell populations, without stimulating Treg lymphocytes. The rcIL-15 injections also stimulated the expression of molecules and transcription factors associated with the activation and effector functions of NK cells, including CD16, NKG2D, NKp30, NKp44, NKp46, perforin, granzyme B, Ly49, T-bet, and Eomes. These results suggest that rcIL-15 might be a valuable therapeutic adjuvant to improve immunity against cancer in dogs.
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Interleucina-15/efeitos adversos , Interleucina-15/imunologia , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/imunologia , Animais , Antígenos CD/metabolismo , Proliferação de Células/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Cães/sangue , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Granzimas/metabolismo , Humanos , Interleucina-15/administração & dosagem , Interleucina-15/toxicidade , Células K562 , Células Matadoras Naturais/metabolismo , Contagem de Leucócitos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/toxicidade , Proteínas com Domínio T/metabolismoRESUMO
BACKGROUND: In this study, we observe the patterns initial palliative treatment for premenopausal patients with HR-positive/HER2-negative MBC and determine if nonadherence to clinical guidelines are associated with worse clinical outcomes in terms of progression-free survival (PFS) and overall survival (OS) in the South Korean population. METHODS: A retrospective review was performed for premenopausal patients diagnosed with HR-positive/HER2-negative MBC between October 1997 and May 2016 who received palliative systemic treatments at a large tertiary medical center. Survival outcomes were analyzed according to the palliative treatment received prior to disease progression. RESULTS: The review identified a total of 272 premenopausal patients meeting study criteria, whose median age was 39 years. Endocrine therapy was the initial treatment in 137 patients (Group 1) with chemotherapy as initial treatment in 135 patients. In the latter group, chemotherapy was continued in 78 patients (Group 2), whereas chemotherapy was switched to endocrine treatment in 57 patients prior to any disease progression (Group 3). Both PFS and OS were significantly longer for chemotherapy-endocrine therapy (median PFS 18.2 months and OS 85.2 months) than for chemotherapy-alone (median PFS 12.6 months and OS 45.5 months) or endocrine therapy-alone (median PFS 7.0 months and OS 57.3 months) (all p values < 0.01). In multivariate analysis, chemotherapy-endocrine therapy was an independent predictive value for improved PFS and OS (hazard ratio [HR] 0.33, 95% CI 0.20-0.52, p < 0.001; HR 0.38, 95% CI 0.19-0.73, p = 0.004). CONCLUSIONS: In our study population, chemotherapy alone was not objectively inferior to endocrine therapy as the initial palliative treatment. In addition, chemotherapy followed by endocrine therapy was associated with objective higher response rate than endocrine therapy alone. Further studies should explore the relationship between non-adherent treatment patterns and patient outcomes across the largely premenopausal breast cancer populations across Asian countries.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Fidelidade a Diretrizes/estatística & dados numéricos , Cuidados Paliativos/normas , Padrões de Prática Médica/estatística & dados numéricos , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/normas , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Pré-Menopausa , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , República da Coreia/epidemiologia , Estudos Retrospectivos , Centros de Atenção Terciária/normas , Centros de Atenção Terciária/estatística & dados numéricos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: The antibody-dependent cellular cytotoxicity (ADCC) is a cell-mediated immune defense mechanism in which effector immune cells actively lyse antibody-coated target cells. The ADCC of tumor cells is employed in the treatment of various cancers overexpressing unique antigens, and only natural killer (NK) cells are known to be major effectors of antibody mediated ADCC activity. Canine NK cells are still defined as non-B, non-T large granular lymphocytes because of the lack of information regarding the NK cell-restricted specific marker in dogs, and it has never been demonstrated that canine NK cells have ADCC ability against tumor cells. In the present study, we investigated whether canine non-B, non-T NK cells have ADCC ability against target antibody-coated tumor cells, using cetuximab and trastuzumab, the only human antibodies reported binding to canine cancer cells. RESULTS: Activated canine non-B, non-T NK cells (CD3-CD21-CD5-TCRαß-TCRγδ-) for 13~17 days ex vivo showed ADCC ability against trastuzumab- or cetuximab-coated target tumor cells expressing various levels of human epidermal growth factor receptor 2 (HER-2) and epidermal growth factor receptor (EGFR). Trastuzumab and cetuximab induced significant ADCC responses of canine NK cells even in CMT-U334 and CF41.Mg cells expressing low levels of HER-2 and/or EGFR, as well as in SKBR3 and DU145 cells overexpressing HER-2 and/or EGFR. The trastuzumab-mediated ADCC activity of NK cells was significantly enhanced by treatment with rcIL-21. CONCLUSIONS: The results of this study suggest that canine non-B, non-T NK lymphocytes have a potential ADCC function and that combinational strategies of monoclonal antibodies with either cytokines, which activate NK cells in vivo, or adoptive transfer of NK cells may be a feasible method for amplifying the efficacy of immunotherapy against malignant cancers even with very low expression of target molecules in dogs.
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Citotoxicidade Celular Dependente de Anticorpos , Células Matadoras Naturais/imunologia , Neoplasias/tratamento farmacológico , Animais , Anticorpos Monoclonais/imunologia , Antineoplásicos Imunológicos/farmacologia , Linhagem Celular Tumoral , Cetuximab/farmacologia , Cães , Receptores ErbB/antagonistas & inibidores , Humanos , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/farmacologiaRESUMO
PURPOSE: Onycholysis and other nail toxicities occur in approximately 20-30% of breast cancer (BC) patients receiving docetaxel chemotherapy. Onycholysis is often associated with painful paronychia, decreasing patients' quality of life. In this study, we aimed to evaluate the efficacy of hydrating nail solution (HNS) (EVONAIL® solution, Evaux Laboratories, France) for the prevention and treatment of docetaxel-induced onycholysis and nail toxicities. METHODS: This study was a prospective, randomized, controlled study of HNS for the prevention or treatment of onycholysis in patients with docetaxel after doxorubicin plus cyclophosphamide. In the experimental arm, patients painted HNS on nails and periungual areas once a day till developing onycholysis grade 2. After grade 2 onycholysis development, patients applied HNS twice a day regardless of treatment arm. The primary endpoints were the incidence of onycholysis grade 2 and recovery rate from grade 2 onycholysis. RESULTS: From August 2015 to May 2016, 103 patients were enrolled and completed this study. Of these, 25 cases of grade 1 and 22 of grade 2 onycholysis were observed. Prophylactic application of HNS resulted in a statistically significant reduction of grade 2 onycholysis compared to controls (P = 0.001) and all grade onycholysis was also significantly lower in the experimental arm (P = 0.034). Multivariate analysis showed that HNS decreased grade 2 onycholysis (Hazard ratio (HR) 0.366, 95% confidence interval (CI) 0.148, 0.902; P = 0.029) and all grade onycholysis (HR 0.372, 95% CI 0.201-0.687, P = 0.002). CONCLUSIONS: Hydrating nail solution significantly reduced the incidence of docetaxel-induced onycholysis in BC patients (NCT02670603).
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Neoplasias da Mama/tratamento farmacológico , Onicólise/prevenção & controle , Soluções Farmacêuticas/administração & dosagem , Taxoides/administração & dosagem , Adulto , Idoso , Quimioterapia Adjuvante , Docetaxel , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Onicólise/induzido quimicamente , Estudos Prospectivos , Taxoides/efeitos adversos , Resultado do Tratamento , Adulto JovemRESUMO
Combination therapy of nucleic acids and chemical drugs for cancer treatment is a promising strategy to enhance the therapeutic efficacy by simultaneously regulating multiple troublesome pathways. In this study, we report on polyethylene glycol-siRNA-polycaprolactone (PEG-siRNA-PCL) micelles that encapsulate hydrophobic drugs for efficient co-delivery of siRNA and drugs to cancer cells. Amphiphilic PEG-siRNA-PCL copolymers were synthesized by annealing antisense siRNA-PCL conjugates with sense siRNA-PEG conjugates. After paclitaxel encapsulation, PEG-siRNA-PCL micelles containing antiapoptotic Bcl-2-specific siRNA were stabilized with linear polyethylenimine via electrostatic interactions. Stabilized PEG-siRNA-PCL micelles showed superior anticancer effects, assessed by caspase-3 activity analysis, apoptotic cell staining, and a cytotoxicity test, to those of paclitaxel-free PEG-siRNA-PCL micelles and unmodified siRNAs. The strong anticancer activity of paclitaxel-incorporated siRNA micelles can be attributed to the synergistic effect of Bcl-2 siRNA and paclitaxel. This work provides an efficient co-delivery platform for combination anticancer therapy with siRNA and chemotherapy.
Assuntos
Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Paclitaxel/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Caspase 3/metabolismo , Portadores de Fármacos/síntese química , Inativação Gênica , Proteínas de Fluorescência Verde/deficiência , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Micelas , Modelos Moleculares , Conformação de Ácido Nucleico , Paclitaxel/farmacologia , Poliésteres/química , Polietilenoglicóis/química , Polietilenoimina/química , Proteínas Proto-Oncogênicas c-bcl-2/deficiência , Proteínas Proto-Oncogênicas c-bcl-2/genéticaRESUMO
The use of stimuli-responsive bioactive molecules is an attractive strategy to circumvent selectivity issues in vivo. Here, we report an activatable cell penetrating peptide (CPP) strategy ultimately aimed at delivering nucleic acid drugs to the colon mucosa using bacterial azoreductase as the local reconversion trigger. Through screening of a panel of CPPs, we identified a sequence (M918) capable of carrying a nucleic acid analogue payload. A modified M918 peptide conjugated to a peptide nucleic acid (PNA) was shown to silence luciferase in colon adenocarcinoma cells (HT-29-luc). Reversible functionalization of the conjugate's lysine residues via an azobenzene self-immolative linkage abolished transfection activity, and the free CPP-PNA was recovered after reduction of the azobenzene bond. This activatable CPP conjugate platform could find applications in the selective delivery of nucleic acid drugs to the colon mucosa, opening therapeutic avenues in colon diseases.
Assuntos
Compostos Azo/química , Peptídeos Penetradores de Células/química , Ácidos Nucleicos Peptídicos/administração & dosagem , Ácidos Nucleicos Peptídicos/química , Polietilenoglicóis/química , Transfecção , Sequência de Aminoácidos , Linhagem Celular Tumoral , Colo/citologia , Colo/metabolismo , Inativação Gênica , Humanos , Dados de Sequência Molecular , Oxirredução , Ácidos Nucleicos Peptídicos/genéticaRESUMO
In this study, we systematically explore the influence of the lipophilic group on the siRNA transfection properties of the polycationic-based delivery vectors. For this, a novel and modular synthetic strategy was developed for the preparation of polymers carrying a cationic site and a lipophilic group at each polymer repeat unit. These bifunctional polymers could form a complex with siRNA and deliver it to human colon carcinoma cells (HT-29-luc). In general, transfection capability increased with an increase in the chain length of the lipophilic moiety. The best transfection agent, a polymer containing ammonium groups and pentyl side chains, exhibited lower toxicity and higher transfection efficiency than branched and linear polyethylenimines (PEI). Moreover, as opposed to PEI, the transfection efficiency of polymer/siRNA complexes remained unchanged in the presence of bafilomycin A1, a proton pump inhibitor, suggesting that the present system did not rely on the "proton sponge" effect for siRNA delivery.
Assuntos
Portadores de Fármacos/química , Polietilenoimina/química , RNA Interferente Pequeno/administração & dosagem , Transfecção/métodos , Portadores de Fármacos/administração & dosagem , Células HT29 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Macrolídeos/farmacologia , Estrutura Molecular , Polietilenoimina/administração & dosagem , RNA Interferente Pequeno/químicaRESUMO
Alcohol consumption, a pervasive societal issue, poses considerable health risks and socioeconomic consequences. Alcohol-induced hepatic disorders, such as fatty liver disease, alcoholic hepatitis, chronic hepatitis, liver fibrosis, and cirrhosis, underscore the need for comprehensive research. Existing challenges in mimicking chronic alcohol exposure in cellular systems, attributed to ethanol evaporation, necessitate innovative approaches. In this study, we developed a simple, reusable, and controllable device for examining the physiological reactions of hepatocytes to long-term alcohol exposure. Our approach involved a novel device designed to continuously release ethanol into the culture medium, maintaining a consistent ethanol concentration over several days. We evaluated device performance by examining gene expression patterns and cytokine secretion alterations during long-term exposure to ethanol. These patterns were correlated with those observed in patients with alcoholic hepatitis. Our results suggest that our ethanol-releasing device can be used as a valuable tool to study the mechanisms of chronic alcohol-mediated hepatic diseases at the cellular level. Our device offers a practical solution for studying chronic alcohol exposure, providing a reliable platform for cellular research. This innovative tool holds promise for advancing our understanding of the molecular processes involved in chronic alcohol-mediated hepatic diseases. Future research avenues should explore broader applications and potential implications for predicting and treating alcohol-related illnesses.
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Chronic myeloid leukemia (CML), caused by BCR::ABL1 fusion gene, is known to regulate disease progression by altering the expression of genes. However, the molecular mechanisms underlying these changes are largely unknown. In this study, we identified RNA Exonuclease 5 (REXO5/LOC81691) as a novel gene with elevated mRNA expression levels in chronic myeloid leukemia (CML) patients. Additionally, using the REXO5 knockout (KO) K562 cell lines, we revealed a novel role for REXO5 in the DNA damage response (DDR). Compared to wild-type (WT) cells, REXO5 KO cells showed an accumulation of R-loops and increased DNA damage. We demonstrated that REXO5 translocates to sites of DNA damage through its RNA recognition motif (RRM) and selectively binds to R loops. Interestingly, we identified that REXO5 regulates R-loop levels by degrading mRNA within R-loop using its exonuclease domain. REXO5 KO showed ATR-CHK1 activation. Collectively, we demonstrated that REXO5 plays a key role in the physiological control of R-loops using its exonuclease domain. These findings may provide novel insights into how REXO5 expression changes contribute to CML pathogenesis.
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Activation of the aminopeptidase (AP) activity of leukotriene A4 hydrolase (LTA4H) presents a potential therapeutic strategy for resolving chronic inflammation. Previously, ARM1 and derivatives were found to activate the AP activity using the alanine-p-nitroanilide (Ala-pNA) as a reporter group in an enzyme kinetics assay. As an extension of this previous work, novel ARM1 derivatives were synthesized using a palladium-catalyzed Ullmann coupling reaction and screened using the same assay. Analogue 5, an aminopyrazole (AMP) analogue of ARM1, was found to be a potent AP activator with an AC50 of 0.12 µM. An X-ray crystal structure of LTA4H in complex with AMP was refined at 2.7 Å. Despite its AP activity with Ala-pNA substrate, AMP did not affect hydrolysis of the previously proposed natural ligand of LTA4H, Pro-Gly-Pro (PGP). This result highlights a discrepancy between the hydrolysis of more conveniently monitored chromogenic synthetic peptides typically employed in assays and endogenous peptides. The epoxide hydrolase (EH) activity of AMP was measured in vivo and the compound significantly reduced leukotriene B4 (LTB4) levels in a murine bacterial pneumonia model. However, AMP did not enhance survival in the murine pneumonia model over a 14-day period. A liver microsome stability assay showed metabolic stability of AMP. The results suggested that accelerated Ala-pNA cleavage is not sufficient for predicting therapeutic potential, even when the full mechanism of activation is known.
Assuntos
Epóxido Hidrolases , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/metabolismo , Animais , Camundongos , Relação Estrutura-Atividade , Humanos , Estrutura Molecular , Aminopeptidases/metabolismo , Aminopeptidases/antagonistas & inibidores , Éteres/farmacologia , Éteres/química , Éteres/síntese química , Relação Dose-Resposta a Droga , Modelos Moleculares , Cristalografia por Raios XRESUMO
Because of RNA's ability to encode structure and functional information, researchers have fabricated diverse geometric structures from this polymer at the micro- and nanoscale. With their tunable structures, rigidity, and biocompatibility, novel two-dimensional and three-dimensional RNA structures can serve as a fundamental platform for biomedical applications, including engineered tissues, biosensors, and drug delivery vehicles. The discovery of the potential of small-interfering RNA (siRNA) has underscored the applications of RNA-based micro- and nanostructures in medicine. Small-interfering RNA (siRNA), synthetic double-stranded RNA consisting of approximately 21 base pairs, suppresses problematic target genes in a sequence-specific manner via inherent RNA interference (RNAi) processing. As a result, siRNA offers a potential strategy for treatment of many human diseases. However, due to inefficient delivery to cells and off-target effects, the clinical application of therapeutic siRNA has been very challenging. To address these issues, researchers have studied a variety of nanocarrier systems for siRNA delivery. In this Account, we describe several strategies for efficient siRNA delivery and selective gene silencing. We took advantage of facile chemical conjugation and complementary hybridization to design novel siRNA-based micro- and nanostructures. Using chemical crosslinkers and hydrophobic/hydrophilic polymers at the end of siRNA, we produced various RNA-based structures, including siRNA block copolymers, micelles, linear siRNA homopolymers, and microhydrogels. Because of their increased charge density and flexibility compared with conventional siRNA, these micro- and nanostructures can form polyelectrolyte complexes with poorly charged and biocompatible cationic carriers that are both more condensed and more homogenous than the complexes formed in other carrier systems. In addition, the fabricated siRNA-based structures are linked by cleavable disulfide bonds for facile generation of original siRNA in the cytosol and for target-specific gene silencing. These newly developed siRNA-based structures greatly enhance intracellular uptake and gene silencing both in vitro and in vivo, making them promising biomaterials for siRNA therapeutics.
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Nanoestruturas/química , RNA Interferente Pequeno/metabolismo , Materiais Biocompatíveis/química , Géis/química , Técnicas de Transferência de Genes , Micelas , Polietilenoglicóis/química , Polímeros/química , Interferência de RNA , RNA Interferente Pequeno/genéticaRESUMO
RNA vaccines have demonstrated their ability to solve the issues posed by the COVID-19 pandemic. This success has led to the renaissance of research into mRNA and their nanoformulations as potential therapeutic modalities for various diseases. The potential of mRNA as a template for synthesizing proteins and protein fragments for cancer immunotherapy is now being explored. Despite the promise, the use of mRNA in cancer immunotherapy is limited by challenges, such as low stability against extracellular RNases, poor delivery efficiency to the target organs and cells, short circulatory half-life, variable expression levels and duration. This review highlights recent advances in chemical modification and advanced delivery systems that are helping to address these challenges and unlock the biological and pharmacological potential of mRNA therapeutics in cancer immunotherapy. The review concludes by discussing future perspectives for mRNA-based cancer immunotherapy, which holds great promise as a next-generation therapeutic modality.
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COVID-19 , Neoplasias , Humanos , RNA Mensageiro , Pandemias , COVID-19/terapia , Imunoterapia , ProteínasRESUMO
Gene therapy is a flourishing field with the potential to revolutionize the treatment of genetic diseases. The emergence of CRISPR-Cas9 has significantly advanced targeted and efficient genome editing. Although CRISPR-Cas9 has demonstrated promising potential applications in various genetic disorders, it faces limitations in simultaneously targeting multiple genes. Novel CRISPR systems, such as Cas12 and Cas13, have been developed to overcome these challenges, enabling multiplexing and providing unique advantages. Cas13, in particular, targets mRNA instead of genomic DNA, permitting precise gene expression control and mitigating off-target effects. This review investigates the potential of Cas12 and Cas13 in ocular gene therapy applications, such as suppression of inflammation and cell death. In addition, the capabilities of Cas12 and Cas13 are explored in addressing potential targets related with disease mechanisms such as aberrant isoforms, mitochondrial genes, cis-regulatory sequences, modifier genes, and long non-coding RNAs. Anatomical accessibility and relative immune privilege of the eye provide an ideal organ system for evaluating these novel techniques' efficacy and safety. By targeting multiple genes concurrently, CRISPR-Cas12 and Cas13 systems hold promise for treating a range of ocular disorders, including glaucoma, retinal dystrophies, and age-related macular degeneration. Nonetheless, additional refinement is required to ascertain the safety and efficacy of these approaches in ocular disease treatments. Thus, the development of Cas12 and Cas13 systems marks a significant advancement in gene therapy, offering the potential to devise effective treatments for ocular disorders.
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Sistemas CRISPR-Cas , Oftalmopatias , Humanos , Sistemas CRISPR-Cas/genética , Edição de Genes , RNA Mensageiro , Olho , Oftalmopatias/genética , Oftalmopatias/terapiaRESUMO
BACKGROUND: Leiomyosarcoma (LMS) has a poor prognosis and rarely originates from the colon. If resection is possible, surgery is the first treatment most commonly considered. Unfortunately, no standard treatment exists for hepatic metastasis of LMS; although, several treatments, such as chemotherapy, radiotherapy, and surgery, have been used. Subsequently, the management of liver metastases remains controversial. CASE SUMMARY: We present a rare case of metachronous liver metastasis in a patient with LMS originating from the descending colon. A 38-year-old man initially reported abdominal pain and diarrhea over the previous two months. Colonoscopy revealed a 4-cm diameter mass in the descending colon, 40 cm from the anal verge. Computed tomography revealed intussusception of the descending colon due to the 4-cm mass. The patient underwent a left hemicolectomy. Immunohistochemical analysis of the tumor revealed that it was positive for smooth muscle actin and desmin, and negative for cluster of differentiation 34 (CD34), CD117, and discovered on gastrointestinal stromal tumor (GIST)-1, which are characteristic of gastrointestinal LMS. A single liver metastasis developed 11 mo post-operatively; the patient subsequently underwent curative resection thereof. The patient remained disease-free after six cycles of adjuvant chemotherapy (doxorubicin and ifosfamide), and 40 and 52 mo after liver resection and primary surgery, respectively. Similar cases were obtained from a search of Embase, PubMed, MEDLINE, and Google Scholar. CONCLUSION: Early diagnosis and surgical resection may be the only potential curative options for liver metastasis of gastrointestinal LMS.
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BACKGROUND: Several studies have suggested a cancer risk reduction in statin users although the evidence remains weak for stomach cancer. The purpose of this study was to use an exact-matching case-control design to examine the risk of gastric cancer associated with the use of statins in a cohort of patients with diabetes. METHODS: Cases were defined as patients with incident gastric cancer identified by International Classification of Diseases 16.0 ~ 16.9 recorded at Samsung Medical Center database during the period of 1999 to 2008, at least 6 months after the entry date of diabetes code. Each gastric cancer case patient was matched with one control patient from the diabetes patient registry in a 1:1 fashion, blinded to patient outcomes. RESULTS: A total of 983 cases with gastric cancer and 983 controls without gastric cancer, matched by age and sex, were included in the analysis. The presence of prescription for any statin was inversely associated with gastric cancer risk in the unadjusted conditional logistic regression model (OR: 0.18; 95% CI: 0.14 - 0.24; P < .0001). Multivariate analysis using conditional logistic regression with Bonferroni's correction against aspirin indicated a significant reduction in the risk of gastric cancer in diabetes patients with statin prescriptions (OR: 0.21; 95% CI: 0.16 - 0.28; P < .0001). After adjustment for aspirin use, a longer duration of statin use was associated with reduced risk of gastric cancer, with statistical significance (P<.0001). CONCLUSIONS: A strong inverse association was found between the risk of gastric adenocarcinoma and statin use in diabetic patients.
Assuntos
Adenocarcinoma/epidemiologia , Diabetes Mellitus/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Gástricas/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de RiscoRESUMO
Ophthalmic neurodegenerative diseases encompass a wide array of molecular pathologies unified by calpain dysregulation. Calpains are calcium-dependent proteases that perpetuate cellular death and inflammation when hyperactivated. Calpain inhibition trials in other organs have faced pharmacological challenges, but the eye offers many advantages for the development and testing of targeted molecular therapeutics, including small molecules, peptides, engineered proteins, drug implants, and gene-based therapies. This review highlights structural mechanisms underlying calpain activation, distinct cellular expression patterns, and in vivo models that link calpain hyperactivity to human retinal and developmental disease. Optimizing therapeutic approaches for calpain-mediated eye diseases can help accelerate clinically feasible strategies for treating calpain dysregulation in other diseased tissues.
Assuntos
Calpaína , Retina , Cálcio/metabolismo , Calpaína/metabolismo , Morte Celular , Humanos , Retina/metabolismoRESUMO
The aminopeptidase activity (AP) of the leukotriene A4 hydrolase (LTA4H) enzyme has emerged as a therapeutic target to modulate host immunity. Initial reports focused on the benefits of augmenting the LTA4H AP activity and clearing its putative pro-inflammatory substrate Pro-Gly-Pro (PGP). However, recent reports have introduced substantial complexity disconnecting the LTA4H modulator 4-methoxydiphenylmethane (4MDM) from PGP as follows: (1) 4MDM inhibits PGP hydrolysis and subsequently inhibition of LTA4H AP activity, and (2) 4MDM activates the same enzyme target in the presence of alternative substrates. Differential modulation of LTA4H by 4MDM was probed in a murine model of acute lung inflammation, which showed that 4MDM modulates the host neutrophilic response independent of clearing PGP. X-ray crystallography showed that 4MDM and PGP bind at the zinc binding pocket and no allosteric binding was observed. We then determined that 4MDM modulation is not dependent on the allosteric binding of the ligand, but on the N-terminal side chain of the peptide. In conclusion, our study revealed that a peptidase therapeutic target can interact with its substrate and ligand in complex biochemical mechanisms. This raises an important consideration when ligands are designed to explain some of the unpredictable outcomes observed in therapeutic discovery targeting LTA4H.