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ETHNOPHARMACOLOGICAL RELEVANCE: The Bazhen decoction is one of the most extensively used Traditional Chinese medicine (TCM) prescriptions for treatment of aging related diseases. However, due to the complexity of the components, the pharmacological mechanism of Bazhen decoction is still limited. AIM OF THE STUDY: In this study, with the aim of helping the clinical precision medicine of TCM, we try out a systematic analysis for dissecting the molecular mechanism of complicated TCM prescription: Bazhen decoction. We identify the pharmacological mechanism of Bazhen decoction in telomere elongation as revealed by systematic analysis. MATERIALS AND METHODS: By RNA sequencing and transcriptome analysis of Bazhen decoction treated wild type cells, we reveal the transcriptome profile induced by Bazhen decoction. We utilized the cells derived from Werner syndrome (WS) mice, which is known to be dysfunctional in telomere elongation due to the deficiency of DNA helicase Wrn. By Western blot, qPCR, Immunofluorescence, flow cytometry, telomere FISH, and SA-ß-Gal staining, we verify the transcriptome data and confirm the pharmacological function of Bazhen decoction and its drug containing serum in telomere elongation and reversing progeroid cell senescence. RESULTS: We reveal that Bazhen decoction may systematically regulate multiple anti-aging pathways, including stem cell regulation, protein homeostasis, cardiovascular function, neuronal function, anti-inflammation, anti-DNA damage induced stress, DNA helicase activity and telomere lengthening. We find that Bazhen decoction and its drug containing serum could up-regulate multiple DNA helicases and telomere regulating proteins. The increased DNA helicases promote the resolving of G-quadruplex (G4) structures, and facilitate DNA replication and telomere elongation. These improvements also endow the cellular resistance to DNA damages induced by replication stress, and rescue the WS caused cellular senescence. CONCLUSIONS: Together these data suggest that Bazhen decoction up-regulate the expression of DNA helicases, thus facilitate G4 resolving and telomere maintenance, which rescue the progeroid cellular senescence and contribute to its anti-aging properties. Our data reveal a new molecular mechanism of Bazhen decoction in anti-aging related diseases via elongating telomere, this may shed light in the application of Bazhen decoction in multiple degenerative diseases caused by telomere erosion.
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Síndrome de Werner , Animales , Ratones , Síndrome de Werner/genética , Daño del ADN , Telómero , Senescencia Celular , ADN Helicasas/genéticaRESUMEN
The chemotherapeutic agent 5-fluorouracil (5-FU) remains the backbone of postoperative adjuvant treatment for gastric cancer. However, fewer than half of patients with gastric cancer benefit from 5-FU-based chemotherapies owing to chemoresistance and limited clinical biomarkers. Here, we identified the SNF2 protein Polo-like kinase 1-interacting checkpoint helicase (PICH) as a predictor of 5-FU chemosensitivity and characterized a transcriptional function of PICH distinct from its role in chromosome separation. PICH formed a transcriptional complex with RNA polymerase II (Pol II) and ATF4 at the CCNA1 promoter in an ATPase-dependent manner. Binding of the PICH complex promoted cyclin A1 transcription and accelerated S-phase progression. Overexpressed PICH impaired 5-FU chemosensitivity in human organoids and patient-derived xenografts. Furthermore, elevated PICH expression was negatively correlated with survival in postoperative patients receiving 5-FU chemotherapy. Together, these findings reveal an ATPase-dependent transcriptional function of PICH that promotes cyclin A1 transcription to drive 5-FU chemoresistance, providing a potential predictive biomarker of 5-FU chemosensitivity for postoperative patients with gastric cancer and prompting further investigation into the transcriptional activity of PICH. SIGNIFICANCE: PICH binds Pol II and ATF4 in an ATPase-dependent manner to form a transcriptional complex that promotes cyclin A1 expression, accelerates S-phase progression, and impairs 5-FU chemosensitivity in gastric cancer.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Resistencia a Antineoplásicos/genética , Ciclina A1 , ADN Helicasas/metabolismo , Fluorouracilo/farmacología , Adenosina Trifosfatasas/uso terapéutico , Quinasa Tipo Polo 1RESUMEN
SMARCA4 (BRG1) and SMARCA2 (BRM) are the two paralogous ATPases of the SWI/SNF chromatin remodeling complexes frequently inactivated in cancers. Cells deficient in either ATPase have been shown to depend on the remaining counterpart for survival. Contrary to this paralog synthetic lethality, concomitant loss of SMARCA4/2 occurs in a subset of cancers associated with very poor outcomes. Here, we uncover that SMARCA4/2-loss represses expression of the glucose transporter GLUT1, causing reduced glucose uptake and glycolysis accompanied with increased dependency on oxidative phosphorylation (OXPHOS); adapting to this, these SMARCA4/2-deficient cells rely on elevated SLC38A2, an amino acid transporter, to increase glutamine import for fueling OXPHOS. Consequently, SMARCA4/2-deficient cells and tumors are highly sensitive to inhibitors targeting OXPHOS or glutamine metabolism. Furthermore, supplementation of alanine, also imported by SLC38A2, restricts glutamine uptake through competition and selectively induces death in SMARCA4/2-deficient cancer cells. At a clinically relevant dose, alanine supplementation synergizes with OXPHOS inhibition or conventional chemotherapy eliciting marked antitumor activity in patient-derived xenografts. Our findings reveal multiple druggable vulnerabilities of SMARCA4/2-loss exploiting a GLUT1/SLC38A2-mediated metabolic shift. Particularly, unlike dietary deprivation approaches, alanine supplementation can be readily applied to current regimens for better treatment of these aggressive cancers.
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Glutamina , Neoplasias , Humanos , Transportador de Glucosa de Tipo 1 , Adenosina Trifosfatasas/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Suplementos Dietéticos , ADN Helicasas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Amyotrophic lateral sclerosis (ALS) is regarded as a fatal neurodegenerative disease that is featured by progressive damage of the upper and lower motor neurons. To date, over 45 genes have been found to be connected with ALS pathology. The aim of this work was to computationally identify unique sets of protein hydrolysate peptides that could serve as therapeutic agents against ALS. Computational methods which include target prediction, protein-protein interaction, and peptide-protein molecular docking were used. The results showed that the network of critical ALS-associated genes consists of ATG16L2, SCFD1, VAC15, VEGFA, KEAP1, KIF5A, FIG4, TUBA4A, SIGMAR1, SETX, ANXA11, HNRNPL, NEK1, C9orf72, VCP, RPSA, ATP5B, and SOD1 together with predicted kinases such as AKT1, CDK4, DNAPK, MAPK14, and ERK2 in addition to transcription factors such as MYC, RELA, ZMIZ1, EGR1, TRIM28, and FOXA2. The identified molecular targets of the peptides that support multi-metabolic components in ALS pathogenesis include cyclooxygenase-2, angiotensin I-converting enzyme, dipeptidyl peptidase IV, X-linked inhibitor of apoptosis protein 3, and endothelin receptor ET-A. Overall, the results showed that AGL, APL, AVK, IIW, PVI, and VAY peptides are promising candidates for further study. Future work would be needed to validate the therapeutic properties of these hydrolysate peptides by in vitro and in vivo approaches.
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Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Humanos , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Simulación del Acoplamiento Molecular , Factor 2 Relacionado con NF-E2/metabolismo , Péptidos/farmacología , Péptidos/metabolismo , Superóxido Dismutasa-1/genética , ADN Helicasas/metabolismo , ARN Helicasas/metabolismo , Enzimas Multifuncionales/metabolismo , Cinesinas/metabolismo , Flavoproteínas/metabolismoRESUMEN
The proper development of male and female gametophytes is critical for successful sexual reproduction and requires a carefully regulated series of events orchestrated by a suite of various proteins. RUVBL1 and RUVBL2, plant orthologues of human Pontin and Reptin, respectively, belong to the evolutionarily highly conserved AAA+ family linked to a wide range of cellular processes. Previously, we found that RUVBL1 and RUVBL2A mutations are homozygous lethal in Arabidopsis. Here, we report that RUVBL1 and RUVBL2A play roles in reproductive development. We show that mutant plants produce embryo sacs with an abnormal structure or with various numbers of nuclei. Although pollen grains of heterozygous mutant plants exhibit reduced viability and reduced pollen tube growth in vitro, some of the ruvbl pollen tubes are capable of targeting ovules in vivo. Similarly, some ruvbl ovules retain the ability to attract wild-type pollen tubes but fail to develop further. The activity of the RUVBL1 and RUVBL2A promoters was observed in the embryo sac, pollen grains, and tapetum cells and, for RUVBL2A, also in developing ovules. In summary, we show that the RUVBL proteins are essential for the proper development of both male and particularly female gametophytes in Arabidopsis.
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Proteínas de Arabidopsis , Arabidopsis , Humanos , Células Germinativas de las Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Polen , Reproducción , Tubo Polínico/genética , Tubo Polínico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , ATPasas Asociadas con Actividades Celulares Diversas/genética , ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismoRESUMEN
Stress granules (SGs) are cytoplasmic biomolecular condensates containing proteins and RNAs in response to stress. Ras-GTPase-activating protein binding protein 1 (G3BP1) is a core SG protein. Caprin-1 and ubiquitin specific peptidase 10 (USP10) interact with G3BP1, facilitating and suppressing SG formation, respectively. The crystal structures of the nuclear transport factor 2-like (NTF2L) domain of G3BP1 in complex with the G3BP1-interacting motif (GIM) of Caprin-1 and USP10 show that both GIMs bind to the same hydrophobic pocket of G3BP1. Moreover, both GIMs suppressed the liquid-liquid phase separation (LLPS) of G3BP1, suggesting that Caprin-1 likely facilitates SG formation via other mechanisms. Thus, we dissected various domains of Caprin-1 and investigated their role in LLPS in vitro and SG formation in cells. The C-terminal domain of Caprin-1 underwent spontaneous LLPS, whereas the N-terminal domain and GIM of Caprin-1 suppressed LLPS of G3BP1. The opposing effect of the N- and C-terminal domains of Caprin-1 on SG formation were demonstrated in cells with or without the endogenous Caprin-1. We propose that the N- and C-terminal domains of Caprin-1 regulate SG formation in a "yin and yang" fashion, mediating the dynamic and reversible assembly of SGs.
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ADN Helicasas , ARN Helicasas , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/metabolismo , ADN Helicasas/metabolismo , Gránulos Citoplasmáticos/metabolismo , Gránulos de Estrés , Proteínas Activadoras de GTPasa/metabolismo , Proteasas Ubiquitina-Específicas/metabolismoRESUMEN
The prevalence of avian infectious bronchitis virus (IBV) is still one of causes inducing severe losses of production in the poultry industry worldwide. Vaccination does not completely prevent IBV infection and spread due to immune failure and viral mutations. ForsythiaeFructus and its compounds have been widely used in a lot of prescriptions of the traditional Chinese medicine for a long history, and it is well-known as safety and efficiency in heat-clearing and detoxifying. This study aims to investigate the anti-IBV activity and mechanism of phillygenin. The results showed that phillygenin inhibited IBV replication by disturbing multiple stages of the virus life cycle, including viral adsorption, invasion, internalization, and release in Vero cells. After being treated with 100, 125 and 150 µg/mL phillygenin, the expression of G3BP1 was significantly increased and the phosphorylation of PKR/eIF2α was activated, which increased stress granule, thereby triggering the antiviral response in Vero cells. The anti-virus activity of PHI was decreased when G3BP1 was interfered by si-RNA, and G3BP1 was down-regulated when PKR/eIF2α was interfered by si-RNA. In conclusion, our findings indicate that phillygenin activates PKR/eIF2α pathway and induces stress granule formation to exert anti-IBV, which holds promise to develop into a novel anti-IBV drug. Further study in vivo is needed to explore phillygenin as a potential and effective drug to prevent IB in poultry.
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Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Animales , Chlorocebus aethiops , ADN Helicasas/metabolismo , ADN Helicasas/farmacología , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 2 Eucariótico de Iniciación/farmacología , Virus de la Bronquitis Infecciosa/fisiología , Lignanos , Proteínas de Unión a Poli-ADP-Ribosa , ARN , ARN Helicasas/metabolismo , ARN Helicasas/farmacología , Proteínas con Motivos de Reconocimiento de ARN , Gránulos de Estrés , Células VeroRESUMEN
PURPOSE: There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. METHODS: We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution cancer risk assessment program. RESULTS: The study included a convenient cohort of 173 women with invasive breast cancer (cases) and 119 women who were cancer-free at the time of ascertainment. The majority of the women self-reported as African-descended (67% for cases and 90.8% for unaffected volunteers). Thirty-seven pathogenic variants were found in 36 (20.8%) patients. While the spectrum of pathogenic variants was heterogeneous, the majority (70.3%) of the pathogenic variants were detected in high-risk genes BRCA1, BRCA2, PALB2, and TP53. Pathogenic variants were also found in the ATM, BARD1, BRIP1, FAM175A, FANCM, NBN, and SLX4 genes in 6.4% of the affected women. Four recurrent pathogenic variants were detected in 11 patients of African ancestry. Only one unaffected woman had a pathogenic variant in the RAD51C gene. Different risk assessment models examined performed well in predicting risk of carrying germline loss-of-function variants in BRCA1 and/or BRCA2 in breast cancer cases. CONCLUSION: The high prevalence and heterogenous spectrum of pathogenic variants identified among self-reported African descendants in Northeast Brazil is consistent with studies in other African ancestry populations with a high burden of aggressive young onset breast cancer. It underscores the need to integrate comprehensive cancer risk assessment and genomic testing in the management of newly diagnosed Black women with breast cancer across the African Diaspora, enabling improved cancer control in admixed underserved and understudied populations.
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Neoplasias de la Mama , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil/epidemiología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , ADN Helicasas/genética , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , MutaciónRESUMEN
INTRODUCTION: CHARGE syndrome (CS, OMIM 214800) is a rare genetic disease characterized by multiple congenital abnormalities, including coloboma, heart defect, atresia of the choanae, retardation of development, genital anomalies, and ear anomalies/deafness. The syndrome is mainly caused by a heterozygous variant in the chromodomain helicase DNA-binding protein 7 (CHD7) gene that encodes the CHD7 protein, involved in the ATP-dependent remodeling of chromatin. METHODS: In this study, the next-generation sequencing targeted panel was used to detect a de novo variant c.3523-2A>G in the CHD7 gene in a patient with severe CS, congenital heart disease, left coloboma of the choroid, cryptorchidism, and congenital deafness. The Sanger sequencing confirmed the variant and clarified it as de novo variant by short tandem repeat analysis in the patient family. We analyzed the effect of a variant by Minigene assay to evaluate the pathogenicity of the variant. RESULTS: In summary, cDNA analysis confirmed that c.3523-2A>G variant activates a cryptic splice site, resulting in 172 base pair missing in exon 15, leading to the premature truncation of the CHD7 protein (p.V1175Afs*11). CONCLUSION: The present study functionally characterized the novel c.3523-2A>G variant in CHD7, providing further confirmatory evidence that it is associated with CS.
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Síndrome CHARGE , Coloboma , Sordera , Adenosina Trifosfato , Síndrome CHARGE/diagnóstico , Síndrome CHARGE/genética , China , Cromatina , Coloboma/genética , ADN Helicasas/genética , ADN Complementario , Proteínas de Unión al ADN/genética , Sordera/genética , Humanos , Masculino , Mutación , Sitios de Empalme de ARNRESUMEN
Although the seroprevalence of Herpes simplex virus type 1 (HSV-1) currently amounts to â¼ 67% worldwide, the annual incidence of a severe disease progression, particularly herpes encephalitis, is approximately 2-4 cases per 1,000,000 infections. Nucleoside analogues, such as acyclovir (ACV), valacyclovir (VACV) or famciclovir, are still the therapeutic treatment of choice for HSV infections. However, nucleoside drugs have limited efficacy against severe HSV disease and for treatment of nucleoside-resistant viral strains, alternative therapies such as helicase-primase inhibitors (HPIs) which are highly potent by inhibiting viral replication are under development. In preclinical studies we analyzed the antiviral efficacy of drug candidates of a novel compound class of HPIs for the treatment of HSV to identify the most active eutomer structure in an intranasal infection mouse lethal challenge model. HSV-1 infected BALB/c mice treated with vehicle control developed fatal disease according to humane endpoints after 5-7 days. In contrast, the animals dosed orally once daily with the HPI compounds at 10 or 4 mg/kg/day showed a significantly increased survival (70% and 100% for 10 mg/kg/day; 90% and 100% for 4 mg/kg/day, respectively) compared to the vehicle treatment (0-10%), when therapy was initiated 6 h post HSV-1 inoculation. We observed a significantly improved outcome in clinical parameters and survival over 21 days in the group receiving novel HPI candidates using even the lowest dose of 4 mg/kg/day. With VACV treatment of 75 mg/kg daily survival was also significantly increased (80%-90% for 75 mg/kg/day) but to lesser extent. Initial IM-250 therapy at 10 mg/kg/day could be delayed up to 72 h resulting in significantly increased survival compared to the vehicle control. Furthermore, we detected significantly fewer viral genome copies in the lungs and brains of HPI treated animals compared to vehicle (440-fold reduction for 4 mg/kg/day IM-250 in the brain) or VACV controls by quantitative PCR. In conclusion the preclinical studies of the novel HPI compounds showed superior efficacy in comparison to the current standard HSV treatment represented by VACV with respect to the survival according humane endpoints, the clinical score and virus load in lungs and brains. Thus, candidates of this new drug class are promising antivirals of HSV infections and further translation into clinical trials is warranted.
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Antivirales/farmacología , ADN Helicasas/antagonistas & inhibidores , ADN Primasa/antagonistas & inhibidores , Herpes Simple/virología , Herpesvirus Humano 1/efectos de los fármacos , Aciclovir/farmacología , Animales , Chlorocebus aethiops , Modelos Animales de Enfermedad , Femenino , Herpes Simple/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Tasa de Supervivencia , Valaciclovir/farmacología , Células Vero , Carga Viral/efectos de los fármacosRESUMEN
The bacterial single-stranded DNA-binding protein (SSB) uses an acidic C-terminal tail to interact with over a dozen proteins, acting as a genome maintenance hub. These SSB-protein interactions are essential, as mutations to the C-terminal tail that disrupt these interactions are lethal in Escherichia coli. While the roles of individual SSB-protein interactions have been dissected with mutational studies, small-molecule inhibitors of these interactions could serve as valuable research tools and have potential as novel antimicrobial agents. This chapter describes a high-throughput screening campaign used to identify inhibitors of SSB-protein interactions. A screen targeting the PriA-SSB interface from Klebsiella pneumoniae is presented as an example, but the methods may be adapted to target nearly any SSB interaction.
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ADN Helicasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Klebsiella pneumoniae/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Sitios de Unión , ADN Helicasas/química , Proteínas de Unión al ADN/química , Evaluación Preclínica de Medicamentos , Ensayos Analíticos de Alto Rendimiento , Modelos Moleculares , Unión Proteica/efectos de los fármacos , Conformación ProteicaRESUMEN
INTRODUCTION: Dedifferentiated endometrial carcinoma is an uncommon highly aggressive uterine tumor. It comprises 2 components: a well-differentiated, low-grade epithelial carcinoma and an undifferentiated carcinoma. The undifferentiated carcinoma frequently exhibits rhabdoid cytologic features. Many of these tumors are characterized by an aberrant switch/sucrose non-fermenting (SWI/SNF) complex. They may also exhibit aberrant expression of mismatch repair (MMR) proteins. Together, these play an important role in the pathogenesis and aggressive nature of the tumor. MATERIAL AND METHODS: We present a case of dedifferentiated endometrial carcinoma in a 63-year-old female showing loss of expression of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4 (SMARCA4/BRG1), and aberrant expression of MMR proteins. We also review the literature starting from the earliest recognition of this entity and the various studies done to explain its molecular pathogenesis and prognostic importance. RESULTS AND CONCLUSIONS: Recognition of SWI/SNF complex-deficient dedifferentiated endometrial carcinoma is important as these tumors do not respond to platinum-based chemotherapy, and consideration of alternative therapies is often necessary. We also want to emphasize that though most of the studies have found MMR deficiency in the undifferentiated carcinoma component, it may be seen only in the low-grade, well-differentiated component, as observed in this case.
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Carcinoma/genética , ADN Helicasas/metabolismo , Neoplasias Endometriales/genética , Neoplasias Complejas y Mixtas/genética , Proteínas Nucleares/metabolismo , Proteína SMARCB1/metabolismo , Factores de Transcripción/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/diagnóstico , Carcinoma/tratamiento farmacológico , Carcinoma/patología , Desdiferenciación Celular/genética , Reparación de la Incompatibilidad de ADN , Resistencia a Antineoplásicos/genética , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/patología , Endometrio/patología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Neoplasias Complejas y Mixtas/diagnóstico , Neoplasias Complejas y Mixtas/tratamiento farmacológico , Neoplasias Complejas y Mixtas/patologíaRESUMEN
KRAS is a key oncogenic driver in lung adenocarcinoma (LUAD). Chromatin-remodeling gene SMARCA4 is comutated with KRAS in LUAD; however, the impact of SMARCA4 mutations on clinical outcome has not been adequately established. This study sought to shed light on the clinical significance of SMARCA4 mutations in LUAD. The association of SMARCA4 mutations with survival outcomes was interrogated in four independent cohorts totaling 564 patients: KRAS-mutant patients with LUAD who received nonimmunotherapy treatment from (a) The Cancer Genome Atlas (TCGA) and (b) the MSK-IMPACT Clinical Sequencing (MSK-CT) cohorts; and KRAS-mutant patients with LUAD who received immune checkpoint inhibitor-based immunotherapy treatment from (c) the MSK-IMPACT (MSK-IO) and (d) the Wake Forest Baptist Comprehensive Cancer Center (WFBCCC) immunotherapy cohorts. Of the patients receiving nonimmunotherapy treatment, in the TCGA cohort (n = 155), KRAS-mutant patients harboring SMARCA4 mutations (KS) showed poorer clinical outcome [P = 6e-04 for disease-free survival (DFS) and 0.031 for overall survival (OS), respectively], compared to KRAS-TP53 comutant (KP) and KRAS-only mutant (K) patients; in the MSK-CT cohort (n = 314), KS patients also exhibited shorter OS than KP (P = 0.03) or K (P = 0.022) patients. Of patients receiving immunotherapy, KS patients consistently exhibited the shortest progression-free survival (PFS; P = 0.0091) in the MSK-IO (n = 77), and the shortest PFS (P = 0.0026) and OS (P = 0.0014) in the WFBCCC (n = 18) cohorts, respectively. Therefore, mutations of SMARCA4 represent a genetic factor leading to adverse clinical outcome in lung adenocarcinoma treated by either nonimmunotherapy or immunotherapy.
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Adenocarcinoma del Pulmón , Estudios de Cohortes , ADN Helicasas/genética , Inmunoterapia , Neoplasias Pulmonares , Mutación , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Factores de Transcripción/genética , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/mortalidad , Adenocarcinoma del Pulmón/terapia , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Tasa de SupervivenciaRESUMEN
Paramutations represent directed and meiotically-heritable changes in gene regulation leading to apparent violations of Mendelian inheritance. Although the mechanism and evolutionary importance of paramutation behaviors remain largely unknown, genetic screens in maize (Zea mays) identify five components affecting 24 nucleotide RNA biogenesis as required to maintain repression of a paramutant purple plant1 (pl1) allele. Currently, the RNA polymerase IV largest subunit represents the only component also specifying proper development. Here we identify a chromodomain helicase DNA-binding 3 (CHD3) protein orthologous to Arabidopsis (Arabidopsis thaliana) PICKLE as another component maintaining both pl1 paramutation and normal somatic development but without affecting overall small RNA biogenesis. In addition, genetic tests show this protein contributes to proper male gametophyte function. The similar mutant phenotypes documented in Arabidopsis and maize implicate some evolutionarily-conserved gene regulation while developmental defects associated with the two paramutation mutants are largely distinct. Our results show that a CHD3 protein responsible for normal plant ontogeny and sperm transmission also helps maintain meiotically-heritable epigenetic regulatory variation for specific alleles. This finding implicates an intersection of RNA polymerase IV function and nucleosome positioning in the paramutation process.
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Ensamble y Desensamble de Cromatina/genética , ADN Helicasas/metabolismo , Proteínas de Plantas/metabolismo , Polen/metabolismo , Zea mays/genética , Alelos , Proteínas de Arabidopsis/genética , ADN Helicasas/genética , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Genotipo , Mutación , Fenotipo , Filogenia , Proteínas de Plantas/genética , Polen/genética , ARN de Planta/genética , ARN Pequeño no Traducido/genética , ARN Pequeño no Traducido/metabolismo , Zea mays/crecimiento & desarrollo , Zea mays/metabolismoRESUMEN
Recent developments in chemotherapy focus on target-specific mechanisms, which occur only in cancer cells and minimize the effects on normal cells. DNA damage and repair pathways are a promising target in the treatment of cancer. In order to identify novel compounds targeting DNA repair pathways, two key proteins, 53BP1 and RAD54L, were tagged with fluorescent proteins as indicators for two major double strand break (DSB) repair pathways: non-homologous end-joining (NHEJ) and homologous recombination (HR). The engineered biosensor cells exhibited the same DNA repair properties as the wild type. The biosensor cells were further used to investigate the DNA repair activities of natural biological compounds. An extract from Phyllosticta sp., the endophyte isolated from the medicinal plant Garcinia cowa Roxb. ex Choisy, was tested. The results showed that the crude extract induced DSB, as demonstrated by the increase in the DNA DSB marker γH2AX. The damaged DNA appeared to be repaired through NHEJ, as the 53BP1 focus formation in the treated fraction was higher than in the control group. In conclusion, DNA repair-based biosensors are useful for the preliminary screening of crude extracts and biological compounds for the identification of potential targeted therapeutic drugs.
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Técnicas Biosensibles , Daño del ADN , Reparación del ADN , Endófitos/química , Garcinia/microbiología , Extractos Vegetales/farmacología , Animales , Línea Celular , Supervivencia Celular , Pollos , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Fermentación , Hongos/metabolismo , Garcinia/metabolismo , Histonas/metabolismo , Recombinación Homóloga , Plantas Medicinales , Semillas/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/metabolismoRESUMEN
Astaxanthin (AST) is a product made from marine organisms that has been used as an anti-cancer supplement. It reduces pontin expression and induces apoptosis in SKBR3, a breast cancer cell line. Using Western blotting and qRT-PCR analyses, this study revealed that in the T47D and BT20 breast cancer cell lines, AST inhibits expression of pontin and mutp53, as well as the Oct4 and Nanog cancer stem cell (CSC) stemness genes. In addition, we explored the mechanism by which AST eradicates breast cancer cells using pontin siRNAs. Pontin knockdown by pontin siRNA reduced proliferation, Oct4 and Nanog expression, colony and spheroid formation, and migration and invasion abilities in breast cancer cells. In addition, reductions in Oct4, Nanog, and mutp53 expression following rottlerin treatment confirmed the role of pontin in these cells. Therefore, pontin may play a central role in the regulation of CSC properties and in cell proliferation following AST treatment. Taken together, these findings demonstrate that AST can repress CSC stemness genes in breast cancer cells, which implies that AST therapy could be used to improve the efficacy of other anti-cancer therapies against breast cancer cells.
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ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proteínas Portadoras/metabolismo , ADN Helicasas/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , ATPasas Asociadas con Actividades Celulares Diversas/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas Portadoras/genética , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , ADN Helicasas/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Mutación , Proteína Homeótica Nanog/genética , Proteína Homeótica Nanog/metabolismo , Invasividad Neoplásica , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Proteína p53 Supresora de Tumor/genética , Xantófilas/farmacologíaRESUMEN
The mechanism of unwinding catalyzed by the hepatitis C virus nonstructural protein 3 helicase (NS3h) has been a subject of considerable interest, with NS3h serving as a prototypical enzyme in the study of helicase function. Recent studies support an ATP-fueled, inchworm-like stepping of NS3h on the nucleic acid that would result in the displacement of the complementary strand of the duplex during unwinding. Here, we describe the screening of a site of incorporation of an unnatural amino acid in NS3h for fluorescent labeling of the enzyme to be used in single-molecule Förster resonance energy transfer (FRET) experiments. From the nine potential sites identified in NS3h for incorporation of the unnatural amino acid, only one allowed for expression and fluorescent labeling of the recombinant protein. Incorporation of the unnatural amino acid was confirmed via bulk assays to not interfere with unwinding activity of the helicase. Binding to four different dsDNA sequences bearing a ssDNA overhang segment of varying length (either minimal 6 or 7 base length overhang to ensure binding or a long 24 base overhang) and sequence was recorded with the new NS3h construct at the single-molecule level. Single-molecule fluorescence displayed time intervals with anticorrelated donor and acceptor emission fluctuations associated with protein binding to the substrates. An apparent FRET value was estimated from the binding events showing a single FRET value of â¼0.8 for the 6-7 base overhangs. A smaller mean value and a broad distribution was in turn recorded for the long ssDNA overhang, consistent with NS3h exploring a larger physical space while bound to the DNA construct. Notably, intervals where NS3h binding was recorded were exhibited at time periods where the acceptor dye reversibly bleached. Protein induced fluorescence intensity enhancement in the donor channel became apparent at these intervals. Overall, the site-specific fluorescent labeling of NS3h reported here provides a powerful tool for future studies to monitor the dynamics of enzyme translocation during unwinding by single-molecule FRET.
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Hepacivirus/enzimología , Imagen Individual de Molécula/métodos , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Azidas/química , Sitios de Unión , ADN/metabolismo , ADN Helicasas/química , ADN Helicasas/metabolismo , Escherichia coli/genética , Transferencia Resonante de Energía de Fluorescencia , Código Genético , Hepacivirus/genética , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Fenilalanina/análogos & derivados , Fenilalanina/química , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas no Estructurales Virales/químicaRESUMEN
Galectin-3 and galectin-3 binding proteins (G3BP) are implicated as key players in metastasis. In the current study, we evaluated the effect of pectic polysaccharides on galectin-3 and G3BP mediated metastasis in vitro (cells) and in vivo (tissues). In vitro study (double immunostaining) confirms the presence of galectin-3 on the cell surface and G3BP in the interlinking region of the cells confirming the role of G3BP in bridging galectin-3 molecules. Dietary carrot (Daucus carota) pectic polysaccharide (CRPP) blocked the expression of galectin-3 and G3BP more effectively (80%), whereas the expressions were reduced to 60% upon treatment with swallow root (Decalepis hamiltonii) pectic polysaccharide (SRPP), ßcarotene and deferoxamine (antiproliferative drug). Ginger (Gingiber officinale) pectic polysaccharide (GRPP) showed only 20% reduction. CRPP reduced 80% of tumor incidence followed by cyclophosphamide - a chemotherapeutic drug (77%), SRPP (67%) and GRPP (45%). Further 3-5 folds reduction in galectin-3/G3BP expression followed by infiltration of macrophages into the deeper layer of the skin by CRPP and SRPP suggested the anticancer property via immunomodulation. Surface Plasmon Resonance (SPR) studies confirm galectin-3 and G3BP interaction, which are disrupted during the treatment with dietary pectic polysaccharides (DPP) (Supplementary Scheme-1). Overall data demonstrate the role of DPPs as potential anticancer alternatives.
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Apoptosis , ADN Helicasas/metabolismo , Carbohidratos de la Dieta/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Polisacáridos/metabolismo , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proteínas Sanguíneas , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Carbohidratos de la Dieta/farmacología , Técnica del Anticuerpo Fluorescente , Galectinas , Expresión Génica , Inmunohistoquímica , Melanoma Experimental , Ratones , Polisacáridos/farmacología , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/metabolismoRESUMEN
OBJECTIVES: SMARCA4-deficient thoracic sarcoma(DTS) is a recently identified new entity of thoracic malignancies characterized by inactivation of SMARCA4. Patients with SMARCA4-DTS have a particulary aggresive clinical course and no effective treatments. However, the detailed clinical features of SMARCA4-DTS remain unclear. Here, we report the clinical courses and molecular profiles of two cases of SMARCA4-DTS. MATERIALS AND METHODS: We experienced strikingly similar two patients of SMARCA4-DTS. The clinicopathologic features were reviewed, and detailed immunohistochemical and comprehensive cancer panel analysis with next generation sequencing confirmed the diagnosis. RESULTS: Our cases had many clinical and radiological observations characteristic of SMARCA4-DTS in common. Immunohistochemical staing showed complete loss of SMARCA4 in tumor cells. Loss of function mutations were detected in SMARCA4. We found that severe SREs comprise a new significant clinical feature of SMARCA4-DTS. CONCLUSION: Integrated clinico-radiologic-pathologic-genetic diagnosis is essential for SMARCA4-DTS and physicians should pay attention to severe SREs during the clinical course of this disease.
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Enfermedades Óseas/diagnóstico , Huesos/patología , ADN Helicasas/genética , Pulmón/patología , Mutación/genética , Proteínas Nucleares/genética , Sarcoma/diagnóstico , Neoplasias Torácicas/diagnóstico , Factores de Transcripción/genética , Biomarcadores de Tumor/genética , Enfermedades Óseas/genética , Enfermedades Óseas/patología , Huesos/diagnóstico por imagen , ADN Helicasas/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunohistoquímica , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Proteínas Nucleares/metabolismo , Pronóstico , Sarcoma/genética , Sarcoma/patología , Neoplasias Torácicas/genética , Neoplasias Torácicas/patología , Factores de Transcripción/metabolismoRESUMEN
Brain aging is accompanied by declining mitochondrial respiration. We hypothesized that mitochondrial morphology and dynamics would reflect this decline. Using hippocampus and frontal cortex of a segmental progeroid mouse model lacking Cockayne syndrome protein B (CSBm/m) and C57Bl/6 (WT) controls and comparing young (2-5 months) to middle-aged mice (13-14 months), we found that complex I-linked state 3 respiration (CI) was reduced at middle age in CSBm/m hippocampus, but not in CSBm/m cortex or WT brain. In hippocampus of both genotypes, mitochondrial size heterogeneity increased with age. Notably, an inverse correlation between heterogeneity and CI was found in both genotypes, indicating that heterogeneity reflects mitochondrial dysfunction. The ratio between fission and fusion gene expression reflected age-related alterations in mitochondrial morphology but not heterogeneity. Mitochondrial DNA content was lower, and hypoxia-induced factor 1α mRNA was greater at both ages in CSBm/m compared to WT brain. Our findings show that decreased CI and increased mitochondrial size heterogeneity are highly associated and point to declining mitochondrial quality control as an initial event in brain aging.