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KRAS gene mutations are common in pancreatic ductal adenocarcinoma (PDAC), but targeting mutant KRAS is still challenging. Here, an endoribonuclease-prepared small interfering RNA (esiRNA) library was used to screen new kinases that play critical roles in PDAC driven by KRAS gene mutations, and serine/threonine kinase 31 (STK31) was identified and characterized as a potential therapeutic target for KRAS-mutant PDAC. Our results showed that STK31 was upregulated in KRAS-mutant PDAC patients with poor survival and highly expressed in PDAC cell lines with KRASG12D mutation. Inhibition of STK31 in KRAS-mutant cell lines significantly reduced PDAC cell growth in vitro and hindered tumor growth in vivo. Gain and loss of function experiments revealed that STK31 is a downstream target of KRAS in PDAC. A pharmacological inhibition assay showed MAPK/ERK signaling involved in STK31 regulation. The further mechanistic study validated that c-Jun, regulated by KRAS/MAPK signaling, directly modulates the transcription level of STK31 by binding to its promoter region. Through RNA sequencing, we found that the cell cycle regulators CCNB1 and CDC25C are downstream targets of STK31. Taken together, our results indicate that STK31, which is the downstream target of the KRAS/MAPK/ERK/c-Jun signaling pathway in KRAS-mutant PDAC, promotes PDAC cell growth by modulating the expression of the cell cycle regulators CCNB1 and CDC25C.
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BACKGROUND AND AIMS: Distinctive gut microbial profiles have been observed between patients with Wilson disease (WD) and healthy individuals. Despite this, the exact relationship and influence of gut microbiota on the advancement of WD-related liver damage remain ambiguous. This research seeks to clarify the gut microbiota characteristics in both human patients and mouse models of WD, as well as their impact on liver injury. METHODS: Gut microbial features in healthy individuals, patients with WD, healthy mice and mice with early- and late-stage WD were analysed using 16S rRNA gene sequencing. Additionally, WD-afflicted mice underwent treatment with either an antibiotic cocktail (with normal saline as a control) or healthy microbiota (using disease microbiota as a control). The study assessed gut microbiota composition, hepatic transcriptome profiles, liver copper concentrations and hepatic pathological injuries. RESULTS: Patients with hepatic WD and mice with WD-related liver injury displayed altered gut microbiota composition, notably with a significant reduction in Lactobacillus abundance. Additionally, the abundances of several gut genera, including Lactobacillus, Veillonella and Eubacterium coprostanoligenes, showed significant correlations with the severity of liver injury in patients with WD. In WD mice, antibiotic treatment or transplantation of healthy microbiota altered the gut microbial structure, increased Lactobacillus abundance and modified the hepatic transcriptional profile. These interventions resulted in reduced hepatic copper concentration and alleviation of WD-related liver injury. CONCLUSIONS: Individuals and mice with pronounced WD-related liver injury exhibited shifts in gut microbial composition. Regulating gut microbiota through healthy microbiota transplantation emerges as a promising therapeutic approach for treating WD-related liver injury.
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Extracellular regulated protein kinases 1/2 (ERK1/2) are key members of multiple signaling pathways, including the ErbB axis. Ectopic ERK1/2 activation contributes to various types of cancer, especially drug resistance to inhibitors of RTK, RAF and MEK, and specific ERK1/2 inhibitors are scarce. In this study, we identified a potential novel covalent ERK inhibitor, Laxiflorin B, which is a herbal compound with anticancer activity. However, Laxiflorin B is present at low levels in herbs; therefore, we adopted a semi-synthetic process for the efficient production of Laxiflorin B to improve the yield. Laxiflorin B induced mitochondria-mediated apoptosis via BAD activation in non-small-cell lung cancer (NSCLC) cells, especially in EGFR mutant subtypes. Transcriptomic analysis suggested that Laxiflorin B inhibits amphiregulin (AREG) and epiregulin (EREG) expression through ERK inhibition, and suppressed the activation of their receptors, ErbBs, via a positive feedback loop. Moreover, mass spectrometry analysis combined with computer simulation revealed that Laxiflorin B binds covalently to Cys-183 in the ATP-binding pocket of ERK1 via the D-ring, and Cys-178 of ERK1 through non-inhibitory binding of the A-ring. In a NSCLC tumor xenograft model in nude mice, Laxiflorin B also exhibited strong tumor suppressive effects with low toxicity and AREG and EREG were identified as biomarkers of Laxiflorin B efficacy. Finally, Laxiflorin B-4, a C-6 analog of Laxiflorin B, exhibited higher binding affinity for ERK1/2 and stronger tumor suppression. These findings provide a new approach to tumor inhibition using natural anticancer compounds.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Camundongos , Animais , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Sistema de Sinalização das MAP Quinases , Camundongos Nus , Simulação por Computador , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mutação , Linhagem Celular TumoralRESUMO
Long non-coding RNA HOX Transcript Antisense RNA (HOTAIR) is overexpressed in multiple cancers with diverse genetic profiles. Importantly, since HOTAIR heavily contributes to cancer progression by promoting tumor growth and metastasis, HOTAIR becomes a potential target for cancer therapy. However, the underlying mechanism leading to HOTAIR deregulation is largely unexplored. Here, we performed a pan-cancer analysis using more than 4,200 samples and found that intragenic exon CpG island (Ex-CGI) was hypermethylated and was positively correlated to HOTAIR expression. Also, we revealed that Ex-CGI methylation promotes HOTAIR expression through enhancing the transcription elongation process. Furthermore, we linked up the aberrant intragenic tri-methylation on H3 at lysine 4 (H3K4me3) and Ex-CGI DNA methylation in promoting transcription elongation of HOTAIR. Targeting the oncogenic CDK7-CDK9-H3K4me3 axis downregulated HOTAIR expression and inhibited cell growth in many cancers. To our knowledge, this is the first time that a positive feedback loop that involved CDK9-mediated phosphorylation of RNA Polymerase II Serine 2 (RNA PolII Ser2), H3K4me3, and intragenic DNA methylation, which induced robust transcriptional elongation and heavily contributed to the upregulation of oncogenic lncRNA in cancer has been demonstrated. Targeting the oncogenic CDK7-CDK9-H3K4me3 axis could be a novel therapy in many cancers through inhibiting the HOTAIR expression.
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Quinase 9 Dependente de Ciclina , Histonas , Neoplasias , RNA Polimerase III , RNA Longo não Codificante , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/metabolismo , Metilação de DNA , Retroalimentação Fisiológica/fisiologia , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , RNA Polimerase III/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
INTRODUCTION: Telomere length (TL) is generally regarded as a biomarker of aging. TL, which is influenced by sociodemographic factors, has been shown to be inversely associated with morbidity. However, most studies examined the youngest, and whether the findings can be extended to older individuals is less clear. Further, few studies have examined these questions in Chinese older adults. This cross-sectional study examined TL and its associated factors in Chinese aged 75+ years in Hong Kong. METHODS: Participants were from the Mr. and Ms. Osteoporosis cohort. A structured interview on sociodemographic factors and physical measurement was conducted. Frailty and sarcopenia status were respectively determined by Fried's criteria and the Asian Working Group for Sarcopenia definition. TL was measured by a molecular inversion probe-quantitative PCR assay and expressed as a novel telomere/a single copy reference gene (T/S) ratio. Adjusted binary logistic regressions were used to examine the associations between TL and the presence of multimorbidity, age-related diseases, frailty, and sarcopenia. RESULTS: Among 555 participants (mean age 83.6 ± 3.8 years, 41.3% females), the mean T/S ratio was 1.01 ± 0.20. Males had a lower T/S ratio (0.97 ± 0.20) compared with females (1.07 ± 0.18) (p < 0.001). A lower education level was related to a longer TL (p = 0.016). Being a current smoker was related to a shorter TL (p = 0.007). TL was not significantly different across categories of age, subjective socioeconomic status, drinking status, physical activity level, and body mass index (p > 0.05). There were no associations between TL and the presence of multimorbidity, diabetes, stroke, cardiovascular diseases, cognitive impairment, frailty, and sarcopenia. CONCLUSION: Among Chinese aged 75+ years, males had shorter TL compared with females. TL was not associated with age-related diseases, frailty, and sarcopenia in this age group. TL may not be a biological marker of aging among older individuals.
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Fragilidade , Sarcopenia , Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Sarcopenia/epidemiologia , Sarcopenia/genética , Fragilidade/epidemiologia , Fragilidade/genética , Estudos Transversais , População do Leste Asiático , Biomarcadores , Telômero/genética , Encurtamento do TelômeroRESUMO
BACKGROUND: Circular RNAs (circRNAs) play important roles in many biological processes. However, the detailed mechanism underlying the critical roles of circRNAs in cancer remains largely unexplored. We aim to explore the molecular mechanisms of circRTN4 with critical roles in pancreatic ductal adenocarcinoma (PDAC). METHODS: CircRTN4 expression level was examined in PDAC primary tumors. The oncogenic roles of circRTN4 in PDAC tumor growth and metastasis were studied in mouse tumor models. Bioinformatics analysis, luciferase assay and miRNA pulldown assay were performed to study the novel circRTN4-miRNA-lncRNA pathway. To identify circRTN4-interacting proteins, we performed circRNA-pulldown and mass spectrometry in PDAC cells. Protein stability assay and 3-Dimensional structure modeling were performed to reveal the role of circRTN4 in stabilizing RAB11FIP1. RESULTS: CircRTN4 was significantly upregulated in primary tumors from PDAC patients. In vitro and in vivo functional studies revealed that circRTN4 promoted PDAC tumor growth and liver metastasis. Mechanistically, circRTN4 interacted with tumor suppressor miR-497-5p in PDAC cells. CircRTN4 knockdown upregulated miR-497-5p to inhibit the oncogenic lncRNA HOTTIP expression. Furthermore, we identified critical circRTN4-intercting proteins by circRNA-pulldown in PDAC cells. CircRTN4 interacted with important epithelial-mesenchymal transition (EMT)- driver RAB11FIP1 to block its ubiquitination site. We found that circRTN4 knockdown promoted the degradation of RAB11FIP1 by increasing its ubiquitination. Also, circRTN4 knockdown inhibited the expression of RAB11FIP1-regulating EMT-markers Slug, Snai1, Twist, Zeb1 and N-cadherin in PDAC. CONCLUSION: The upregulated circRTN4 promotes tumor growth and liver metastasis in PDAC through the novel circRTN4-miR-497-5p-HOTTIP pathway. Also, circRTN4 stabilizes RAB11FIP1 to contribute EMT.
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Transição Epitelial-Mesenquimal , MicroRNAs/genética , Proteínas Nogo/genética , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/metabolismo , RNA Circular , RNA Longo não Codificante/genética , Adulto , Idoso , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Interferência de RNARESUMO
Rheumatoid arthritis (RA) is one of the complex diseases with the involvement of the genetic as well as environmental factors in its onset and severity. Different genome-wide association and candidate gene studies have shown the role of several genetic variants in multiple loci/genes with ethnical and geographical variations. This study was designed to detect the association of a single-nucleotide polymorphism (SNP) rs10865035 in the AFF3 gene with the genetic background of rheumatoid arthritis (RA) in the Pakistani cohort. A total of 703 individuals, including 409 RA patients and 294 healthy controls, were genotyped using TaqMan assay and Tri primer ARMS-PCR (amplification-refractory mutation system-polymerase chain reaction) methods. The association of rs10865035 with the RA was statistically determined using different models. Interestingly, besides the homozygous recessive model (G/G vs. A/G + A/A) (OR = 1.693(1.06-2.648); P = 0.025), all other models, which included the codominant (χ 2 = 5.169; P = 0.075), homozygous dominant (A/A vs. G/G + A/G) (OR = 0.867 (0.636-1.187); P = 0.41), heterozygous (A/G vs. A/A + GG) (OR = 0.491 (0.667-1.215); P = 0.49), and additive model (OR = 0.826 (0.665-1.027); P = 0.08) showed insignificant distribution of the genotypes among the cases and controls. These findings suggest that the AFF3 gene (rs10865035) has no significant role in the onset of RA in the Pakistani population.
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Artrite Reumatoide , Estudo de Associação Genômica Ampla , Artrite Reumatoide/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Genótipo , Humanos , Proteínas Nucleares , Paquistão , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
MicroRNA-34a (miR-34a) is frequently downregulated in pancreatic ductal adenocarcinoma (PDAC) cells, however, the silencing mechanism remains unclear. Enhancer of zeste homolog 2 (EZH2) is overexpressed in PDAC, and our previous miRNA profiling showed that inhibition of EZH2 in PDAC cells led to the re-expression of a group of tumor suppressor miRNAs including miR-34a. Here, we studied the effect of ectopic EZH2 expression to the silencing of miR-34a, and identified HOTAIR as an interacting partner to induce heterochromatin formation during miR-34a repression. We identified EZH2 as a major player in silencing miR-34a. Inhibition of EZH2 upregulated miR-34a expression in PDAC cells, while EZH2 overexpression in human pancreatic ductal epithelial (HPDE) cells repressed miR-34a expression and decreased the miR-34a promoter activity. We then showed that HOTAIR played a critical role in EZH2-mediated repression of miR-34a, as knockdown of HOTAIR attenuated the miR-34a inhibition effect in EZH2-overexpressing HPDE cells. HOTAIR physically interacted with miR-34a promoter, and the EZH2-interacting region located at 5' HOTAIR RNA was essential in repressing miR-34a and promoting cell proliferation. More importantly, we showed that the interaction between EZH2 and HOTAIR underlay the silencing of miR-34a through induction of heterochromatin formation. We first showed that manipulation of EZH2 level interfered the occupancy of heterochromatin markers H3K9me2, heterochromatin associated protein 1α and 1γ in PDAC cells. In turn, we showed that knockdown of HOTAIR reduced the occupancy of EZH2 at miR-34a promoter. The identification of HOTAIR-guided miR-34a silencing opened a new avenue in miR-34a-oriented therapy against PDAC.
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Carcinoma Ductal Pancreático/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Heterocromatina/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética , Animais , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Regiões Promotoras GenéticasRESUMO
P2Y receptor activation causes the release of inflammatory cytokines in the bronchial epithelium, whereas G protein-coupled estrogen receptor (GPER), a novel estrogen (E2) receptor, may play an anti-inflammatory role in this process. We investigated the cellular mechanisms underlying the inhibitory effect of GPER activation on the P2Y receptor-mediated Ca(2+) signaling pathway and cytokine production in airway epithelia. Expression of GPER in primary human bronchial epithelial (HBE) or 16HBE14o- cells was confirmed on both the mRNA and protein levels. Stimulation of HBE or 16HBE14o- cells with E2 or G1, a specific agonist of GPER, attenuated the nucleotide-evoked increases in [Ca(2+)]i, whereas this effect was reversed by G15, a GPER-specific antagonist. G1 inhibited the secretion of two proinflammatory cytokines, interleukin (IL)-6 and IL-8, in cells stimulated by adenosine 5'-(γ-thio)triphosphate (ATPγS). G1 stimulated a real-time increase in cAMP levels in 16HBE14o- cells, which could be inhibited by adenylyl cyclase inhibitors. The inhibitory effects of E2 or G1 on P2Y receptor-induced increases in Ca(2+) were reversed by treating the cells with a protein kinase A (PKA) inhibitor. These results demonstrated that the inhibitory effects of G1 or E2 on P2Y receptor-mediated Ca(2+) mobilization and cytokine secretion were due to GPER-mediated activation of a cAMP-dependent PKA pathway. This study has reported, for the first time, the expression and function of GPER as an anti-inflammatory component in human bronchial epithelia, which may mediate through its opposing effects on the pro-inflammatory pathway activated by the P2Y receptors in inflamed airway epithelia.
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Cálcio/metabolismo , Epitélio/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Purinérgicos P2Y/metabolismo , Transdução de Sinais/fisiologia , Brônquios/metabolismo , Linhagem Celular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Estrogênios/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Mucosa Respiratória/metabolismoRESUMO
Hepatocellular carcinoma (HCC) is a worldwide threat to public health, especially in China, where chronic hepatitis B virus (HBV) infection is found in 80-90% of all HCCs. The HBV-encoded X antigen (HBx) is a trans-regulatory protein involved in virus-induced hepatocarcinogenesis. Although the carboxyl-terminus-truncated HBx, rather than the full-length counterpart, is frequently overexpressed in human HCCs, its functional mechanisms are not fully defined. We investigated the molecular function of a naturally occurring HBx variant which has 35 amino acids deleted at the C-terminus (HBxΔ35). Genome-wide scanning analysis and PCR validation identified growth arrest-specific 2 (GAS2) as a direct target of HBxΔ35 at transcriptional level in human immortalized liver cells. HBxΔ35 was found to bind the promoter region of GAS2 and attenuate its expression to promote hepatocellular proliferation and tumourigenicity. Further functional assays demonstrated that GAS2 induces p53-dependent apoptosis and senescence to counteract HBxΔ35-mediated tumourigenesis. Notably, GAS2 expression was significantly down-regulated in HCCs compared with the corresponding normal tissues. In conclusion, our integrated study uncovered a novel viral mechanism in hepatocarcinogenesis, wherein HBxΔ35 deregulates cell growth via direct silencing of GAS2 and thereby provides a survival advantage for pre-neoplastic hepatocytes to facilitate cancer development.
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Apoptose , Carcinoma Hepatocelular/metabolismo , Ciclo Celular , Transformação Celular Viral , Senescência Celular , Inativação Gênica , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Transativadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Sítios de Ligação , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Hepatite B/complicações , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas dos Microfilamentos/genética , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Tempo , Transativadores/genética , Transcrição Gênica , Transfecção , Carga Tumoral , Proteína Supressora de Tumor p53/genética , Proteínas Virais Reguladoras e AcessóriasRESUMO
Chronic inflammation is believed to play crucial roles in the pathogenesis of various diseases. Several types of drugs are used to treat inflammatory disorders, but they cause adverse side effects. Natural products are alternatives to these drugs which offer hope for discovery of bioactive lead compounds that may be developed into drugs for treatment of inflammatory disorders. The biological and chemical diversity of marine habitats constitutes a sizeable reservoir of novel compounds. Some of them, like sesquiterpenoids, diterpenes, steroids, polysaccharides, alkaloids, fatty acids, proteins, and other chemical compounds, isolated from marine organisms are found to exhibit anti-inflammatory activity. This review reports some recent (2011-2015) investigations and examples of marine natural products and their synthetic derivatives with anti-inflammatory activity. It also highlights those compounds that are currently undergoing preclinical or clinical evaluation.
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Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Organismos Aquáticos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologiaRESUMO
Ellagitannin is a common compound in food and herbs, but there are few detailed studies on the metabolism of purified ellagitannins. FR429 is a purified ellagitannin with antitumor potential, which is from Polygonum capitatum Buch.-Ham.ex D. Don. The present study was designed to investigate the metabolic profiles of FR429 in rats in vivo. Using liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LC/MS(n)-IT-TOF), total eight metabolites were found in rat bile and urine after intravenous administration of FR429, but could not be detected in plasma. These metabolites were ellagic acid, mono-methylated FR429, ellagic acid methyl ether glucuronide, ellagic acid methyl ether diglucuronide, ellagic acid dimethyl ether glucuronide, and ellagic acid dimethyl ether diglucuronide. It was concluded that methylation and subsequent glucuronidation were the major metabolic pathways of FR429 in rats in vivo. This is the first report on the in vivo metabolism of the purified ellagitannin in rats.
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Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/farmacocinética , Polygonum/química , Animais , Masculino , Espectrometria de Massas , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Berberine (BBR), as a new medicine for hyperlipidemia, can reduce the blood lipids in patients. Mechanistic studies have shown that BBR activates the extracellular-signal regulated kinase pathway by stabilizing low-density-lipoprotein receptor mRNA. However, aside from inhibiting the intestinal absorption of cholesterol, the effects of BBR on other metabolic pathways of cholesterol have not been reported. This study aimed to investigate the action of BBR on the excretion of cholesterol in high-fat diet-induced hyperlipidemic hamsters. METHODS: Golden hamsters were fed a high-fat diet (HFD) for 6 weeks to induce hyperlipidemia, followed by oral treatment with 50 and 100 mg/kg/day of BBR or 10 and 30 mg/kg/day of lovastatin for 10 days, respectively. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), transaminases, and total bile acid in the serum, liver, bile and feces were measured using an enzyme-linked immunosorbent assay. The cholesterol (as well as coprostanol) levels in the liver, bile and feces were determined by gas chromatography-mass spectrometry. RESULTS: The HFD hamsters showed significantly hyperlipidemic characteristics compared with the normal hamsters. Treatment with BBR for 10 days reduced the serum TC, TG and LDL-C levels in HFD hamsters by 44-70, 34-51 and 47-71%, respectively, and this effect was both dose- and time-dependent. Initially, a large amount of cholesterol accumulated in the hyperlipidemic hamster livers. After BBR treatment, reductions in the liver cholesterol were observed by day 3 and became significant by day 7 at both doses (P < 0.001). Meanwhile, bile cholesterol was elevated by day 3 and significantly increased at day 10 (P < 0.001). BBR promoted cholesterol excretion from the liver into the bile in hyperlipidemic hamsters but not in normal hamsters, and these results provide a link between the cholesterol-lowering effect of BBR with cholesterol excretion into the bile. CONCLUSIONS: We conclude that BBR significantly promoted the excretion of cholesterol from the liver to the bile in hyperlipidemic hamsters, which led to large decreases in the serum TC, TG and LDL-C levels. Additionally, compared with lovastatin, the BBR treatment produced no obvious side effects on the liver function.
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Berberina/uso terapêutico , Colesterol/metabolismo , Gorduras na Dieta , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/metabolismo , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , LDL-Colesterol/metabolismo , Cricetinae , Dieta Hiperlipídica , Ensaio de Imunoadsorção Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lovastatina/uso terapêutico , Masculino , Mesocricetus , RNA Mensageiro/metabolismo , Fatores de Tempo , Triglicerídeos/metabolismo , gama-Glutamiltransferase/metabolismoRESUMO
OBJECTIVE: Bone morphogenic protein 4 (BMP4) is involved in the development of endothelial dysfunction in hypertension. This study investigated whether the inhibition of BMP4 signaling improves endothelial function in db/db diabetic mice. APPROACH AND RESULTS: Male db/db mice were treated with noggin via osmotic pump infusion (1 µg/[h·kg(-1)]) for 2 weeks. Adenovirus BMP4-short hairpin RNA was introduced via tail vein injection at a dosage of 10(9) pfu/mouse and its effects were examined 7 days after. Vasoreactivity was studied on wire and pressure myograph. Both noggin treatment and adenovirus BMP4-short hairpin RNA transduction improved endothelium-dependent relaxations in aortae and flow-mediated dilatation in mesenteric arteries of db/db mice. Ex vivo treatment with BMP4 inhibitors and adenovirus BMP4-short hairpin RNA rescued the impaired endothelium-dependent relaxations in db/db mouse aortae and reduced reactive oxygen species overproduction determined by dihydroethidium staining, CM-H2DCFDA fluorescence imaging, and chemiluminescence assay in db/db mouse aortae, and also in ex vivo cultured C57BL/6 mouse aortae or primary mouse aortic endothelial cells treated with high glucose. Likewise, activin receptor-like kinase 3 silencing by short hairpin RNA lentivirus improved endothelium-dependent relaxations in db/db mouse aortae accompanied by reactive oxygen species inhibition in endothelial cells. In addition, noggin reduced BMP4 upregulation in high-glucose-treated endothelial cells and in C57BL/6 mouse aortae and in aortae from db/db mice. CONCLUSIONS: Inhibition of BMP4/activin receptor-like kinase 3/reactive oxygen species signaling improved endothelial function in diabetic mice through limiting oxidative stress in endothelium. Inhibiting BMP4 cascade can become another potential therapeutic strategy against diabetic vascular dysfunction.
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Proteína Morfogenética Óssea 4/antagonistas & inibidores , Proteínas de Transporte/farmacologia , Angiopatias Diabéticas/terapia , Endotélio Vascular/efeitos dos fármacos , Terapia Genética/métodos , Interferência de RNA , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Adenoviridae/genética , Animais , Glicemia/metabolismo , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Células Cultivadas , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Vetores Genéticos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Vasodilatadores/farmacologiaRESUMO
Non-coding RNA refers to a large group of endogenous RNA molecules that have no protein coding capacity, while having specialized cellular and molecular functions. They possess wide range of functions such as the regulation of gene transcription and translation, post-transcriptional modification, epigenetic landscape establishment, protein scaffolding and cofactors recruitments. They are further divided into small non-coding RNAs with size < 200nt (e.g. miRNA, piRNA) and long non-coding RNAs with size >= 200nt (e.g. lincRNA, NAT). Increasing evidences suggest that both non-coding RNAs groups play important roles in cancer development, progression and pathology. Clinically, non-coding RNAs aberrations show high diagnostic and prognostic values. With improved understanding of the nature and roles of non-coding RNAs, it is believed that we can develop therapeutic treatment against cancer via the modulation of these RNA molecules. Advances in nucleic acid drug technology and computational simulation prompt the development of agents to intervene the malignant effects of non-coding RNAs. In this review, we will discuss the role of non-coding RNAs in cancer, and evaluate the potential of non-coding RNA-based cancer therapies.
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Stem-cell antigen 1-positive (Sca-1+) cardiac stem cells (CSCs), a vital kind of CSCs in humans, promote cardiac repair in vivo and can differentiate to cardiomyocytes with 5'-azacytizine treatment in vitro. However, the underlying molecular mechanisms are unknown. ß-arrestin2 is an important scaffold protein and highly expressed in the heart. To explore the function of ß-arrestin2 in Sca-1+ CSC differentiation, we used ß-arrestin2-knockout mice and overexpression strategies. Real-time PCR revealed that ß-arrestin2 promoted 5'-azacytizine-induced Sca-1+ CSC differentiation in vitro. Because the microRNA 155 (miR-155) may regulate ß-arrestin2 expression, we detected its role and relationship with ß-arrestin2 and glycogen synthase kinase 3 (GSK3ß), another probable target of miR-155. Real-time PCR revealed that miR-155, inhibited by ß-arrestin2, impaired 5'-azacytizine-induced Sca-1+ CSC differentiation. On luciferase report assay, miR-155 could inhibit the activity of ß-arrestin2 and GSK3ß, which suggests a loop pathway between miR-155 and ß-arrestin2. Furthermore, ß-arrestin2-knockout inhibited the activity of GSK3ß. Akt, the upstream inhibitor of GSK3ß, was inhibited in ß-arrestin2-Knockout mice, so the activity of GSK3ß was regulated by ß-arrestin2 not Akt. We transplanted Sca-1+ CSCs from ß-arrestin2-knockout mice to mice with myocardial infarction and found similar protective functions as in wild-type mice but impaired arterial elastance. Furthermore, low level of ß-arrestin2 agreed with decreased phosphorylation of AKT and increased phophorylation of GSK3ß, similar to in vitro findings. The ß-arrestin2/miR-155/GSK3ß pathway may be a new mechanism with implications for treatment of heart disease.
Assuntos
Arrestinas/fisiologia , Azacitidina/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/citologia , Ataxias Espinocerebelares/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Imunofluorescência , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta-ArrestinasRESUMO
BACKGROUND & AIMS: Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that is overexpressed by pancreatic ductal adenocarcinoma (PDAC) cells and increases their aggressiveness. We identified microRNAs (miRs) that are regulated by EZH2 and studied their functions in PDAC cells. METHODS: We performed miR profile analysis of PDAC cells incubated with EZH2 inhibitor 3-deazaneplanocin A, and pancreatic ductal epithelial cells that overexpressed EZH2. Expression levels of miRs and the targets of miRs were analyzed by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. We expressed different forms of EZH2 to analyze functional domains and used small interfering RNAs to reduce its level in PDAC cells. RESULTS: Expression of miR-218 was repressed by EZH2 in PDAC cells. Levels of miR-218 were significantly reduced in primary PDAC tumor samples compared with paired, adjacent nontumor tissue. Overexpression of miR-218 in SW1990 cells reduced their proliferation and tumor formation and metastasis in nude mice. Loss of miR-218 from SW1990 cells increased levels of UDP-glycosyltransferase 8 and miR-218 was found to bind to its 3'-UTR. Levels of UDP-glycosyltransferase protein and messenger RNA were associated with the metastatic potential of PDAC cell lines and progression of tumors in patients. EZH2 was found to silence miR-218 by binding to its promoter, promoting heterochromatin formation, and recruiting the DNAs methyltransferase 1, 3A, and 3B. CONCLUSIONS: EZH2 is up-regulated in PDAC samples from patients and silences miR-218. MicroRNA-218 prevents proliferation of PDAC cells in culture, and tumor growth and metastasis in nude mice. MicroRNA-218 reduces levels of UDP-glycosyltransferase, which is associated with the metastatic potential of PDAC tumors in mice and progression of human PDAC.
Assuntos
Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Heterocromatina/metabolismo , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Complexo Repressor Polycomb 2/genética , RNA Neoplásico/genética , Animais , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Neoplasias Experimentais , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Complexo Repressor Polycomb 2/biossíntese , RNA Neoplásico/biossíntese , Elementos Silenciadores TranscricionaisRESUMO
Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and is the third most common cause of cancer-related deaths. Currently available treatment options for HCC patients are scarce resulting in an urgent need to develop a novel effective cure. Polygonum capitatum is a medicinal herb which has been used to treat inflammatory diseases in Miao nationality of China. We recently isolated a pure compound davidiin from P. capitatum extract. Four HCC cell lines were treated with davidiin. Cell viability was recorded by MTT assay. siRNAs targeting enhancer of zeste homolog 2 (EZH2) were applied to modulate the expression of EZH2. Established xenograft mice models of HCC were applied to evaluate the in vivo anticancer activity of davidiin. We investigated the anticancer activity and the underlying mechanism of davidiin. The compound inhibited HCC cell growth and also suppressed tumor growth in xenografted HCC mouse. Such inhibition was facilitated by specifically downregulation on EZH2. The compound possesses anticancer activity both in vitro and in vivo which warrants further clinical investigation as a potential anti-HCC agent.
Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Neoplasias Hepáticas/genética , Complexo Repressor Polycomb 2/genética , Taninos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Potenciadora do Homólogo 2 de Zeste , Técnicas de Silenciamento de Genes , Humanos , Taninos Hidrolisáveis/química , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Taninos/química , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Polygonum capitatum Buch.-Ham.ex D. Don, a traditional Miao-nationality herbal medicine, has been widely used in the treatment of various urologic disorders. Recent pharmacological studies demonstrated that a pure compound, FR429, isolated from the ethanol extracts of P. capitatum could selectively inhibit the growth of four hepatocellular carcinoma (HCC) cell lines in a dose-dependent manner. Thus, P. capitatum probably exhibits potential antitumor activity. However, there is very little information on the metabolism of substances present in P. capitatum extracts. In this study, gallic acid, quercetrin, ethanol extracts and ethyl acetate fraction of ethnolic extract (EtOAc fraction) of P. capitatum were cultured anaerobically with rat intestinal bacteria. A highly sensitive and selective liquid chromatography electrospray ionization-ion trap-time of fight mass spectrometry (LC/MSn-IT-TOF) technique was employed to identify and characterize the resulting metabolites. A total of 22 metabolites (M1-M22), including tannins, phenolic acids and flavonoids, were detected and characterized. The overall results demonstrated that the intestinal bacteria played an important role in the metabolism of P. capitatum, and the main metabolic pathways were hydrolysis, reduction and oxidation reactions. Our results provided a basis for the estimation of the metabolic transformation of P. capitatum in vivo.
Assuntos
Bactérias/metabolismo , Biotransformação , Medicamentos de Ervas Chinesas/química , Metaboloma , Plantas Medicinais/química , Polygonum/química , Polygonum/metabolismo , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacologia , Ácido Gálico/química , Ácido Gálico/metabolismo , Humanos , Intestinos/microbiologia , Masculino , Espectrometria de Massas , Redes e Vias Metabólicas , Metabolômica , Microbiota/efeitos dos fármacos , Quercetina/análogos & derivados , Quercetina/química , Quercetina/metabolismo , RatosRESUMO
mRNA emerged as an attractive therapy modality with the development of mRNA structure engineering techniques and delivery platforms. mRNA therapeutics, applied for vaccine therapy, protein replacement therapy, and chimeric antigen receptor (CAR) T cell-based therapy, has shown huge potential in treating a wide range of diseases, such as cancer and rare genetic diseases, with successful and exciting preclinical and clinical progress. In mRNA therapeutics, a potent delivery system is key to the success of its application for disease treatment. Herein, different types of mRNA delivery strategies, including nanoparticles produced from lipid or polymer materials, virus-based platforms, and exosome-based platforms, are mainly focused.