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1.
Cell Commun Signal ; 22(1): 6, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166927

RESUMEN

Ferroptosis is a newly discovered form of cell death that is featured in a wide range of diseases. Exosome therapy is a promising therapeutic option that has attracted much attention due to its low immunogenicity, low toxicity, and ability to penetrate biological barriers. In addition, emerging evidence indicates that exosomes possess the ability to modulate the progression of diverse diseases by regulating ferroptosis in damaged cells. Hence, the mechanism by which cell-derived and noncellular-derived exosomes target ferroptosis in different diseases through the system Xc-/GSH/GPX4 axis, NAD(P)H/FSP1/CoQ10 axis, iron metabolism pathway and lipid metabolism pathway associated with ferroptosis, as well as its applications in liver disease, neurological diseases, lung injury, heart injury, cancer and other diseases, are summarized here. Additionally, the role of exosome-regulated ferroptosis as an emerging repair mechanism for damaged tissues and cells is also discussed, and this is expected to be a promising treatment direction for various diseases in the future. Video Abstract.


Asunto(s)
Exosomas , Ferroptosis , Lesión Pulmonar , Humanos , Muerte Celular , NAD
2.
Bioorg Med Chem ; 93: 117454, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37659218

RESUMEN

Bacterial infection, which is still one of the leading causes of death in humans, poses an enormous threat to the worldwide public health system. Antibiotics are the primary medications used to treat bacterial diseases. Currently, the discovery of antibiotics has reached an impasse, and due to the abuse of antibiotics resulting in bacterial antibiotic resistance, researchers have a critical desire to develop new antibacterial agents in order to combat the deteriorating antibacterial situation. Natural chalcones, the flavonoids consisting of two phenolic rings and a three-carbon α, ß-unsaturated carbonyl system, possess a variety of biological and pharmacological properties, including anti-cancer, anti-inflammatory, antibacterial, and so on. Due to their potent antibacterial properties, natural chalcones possess the potential to become a new treatment for infectious diseases that circumvents existing antibiotic resistance. Currently, the majority of research on natural chalcones focuses on their synthesis, biological and pharmacological activities, etc. A few studies have been conducted on their antibacterial activity and mechanism. Therefore, this review focuses on the antibacterial activity and mechanisms of seventeen natural chalcones. Firstly, seventeen natural chalcones have been classified based on differences in antibacterial mechanisms. Secondly, a summary of the isolation and biological activity of seventeen natural chalcones was provided, with a focus on their antibacterial activity. Thirdly, the antibacterial mechanisms of natural chalcones were summarized, including those that act on bacterial cell membranes, biological macromolecules, biofilms, and quorum sensing systems. This review aims to lay the groundwork for the discovery of novel antibacterial agents based on chalcones.


Asunto(s)
Chalconas , Humanos , Chalconas/farmacología , Flavonoides , Antibacterianos/farmacología , Biopelículas , Carbono
3.
Int J Mol Sci ; 24(7)2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37047479

RESUMEN

Galactooligosaccharides (GOS) are one of the most important functional oligosaccharide prebiotics. The surface display of enzymes was considered one of the most excellent strategies to obtain these products. However, a rough industrial environment would affect the biocatalytic process. The catalytic process could be efficiently improved using biofilm-based fermentation with high resistance and activity. Therefore, the combination of the surface display of ß-galactosidase and biofilm formation in Pichia pastoris was constructed. The results showed that the catalytic conversion rate of GOS was up to 50.3% with the maximum enzyme activity of 5125 U/g by screening the anchorin, and the number of the continuous catalysis batches was up to 23 times. Thus, surface display based on biofilm-immobilized fermentation integrated catalysis and growth was a co-culture system, such that a dynamic equilibrium in the consolidated integrative process was achieved. This study provides the basis for developing biofilm-based surface display methods in P. pastoris during biochemical production processes.


Asunto(s)
Pichia , Saccharomycetales , Biocatálisis , Pichia/genética , Pichia/metabolismo , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo , Saccharomycetales/metabolismo , Fermentación , Proteínas Recombinantes/metabolismo
4.
Cancer Sci ; 113(2): 459-477, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34811848

RESUMEN

A high-fat diet (HFD) leads to long-term exposure to gut microbial metabolite secondary bile acids, such as deoxycholic acid (DCA), in the intestine, which is closely linked to colorectal cancer (CRC). Evidence reveals that vasculogenic mimicry (VM) is a critical event for the malignant transformation of cancer. Therefore, this study investigated the crucial roles of DCA in the regulation of VM and the progression of intestinal carcinogenesis. The effects of an HFD on VM formation and epithelial-mesenchymal transition (EMT) in human CRC tissues were investigated. The fecal DCA level was detected in HFD-treated Apcmin/+ mice. Then the effects of DCA on VM formation, EMT, and vascular endothelial growth factor receptor 2 (VEGFR2) signaling were evaluated in vitro and in vivo. Here we demonstrated that compared with a normal diet, an HFD exacerbated VM formation and EMT in CRC patients. An HFD could alter the composition of the gut microbiota and significantly increase the fecal DCA level in Apcmin/+ mice. More importantly, DCA promoted tumor cell proliferation, induced EMT, increased VM formation, and activated VEGFR2, which led to intestinal carcinogenesis. In addition, DCA enhanced the proliferation and migration of HCT-116 cells, and induced EMT process and vitro tube formation. Furthermore, the silence of VEGFR2 reduced DCA-induced EMT, VM formation, and migration. Collectively, our results indicated that microbial metabolite DCA promoted VM formation and EMT through VEGFR2 activation, which further exacerbated intestinal carcinogenesis.


Asunto(s)
Carcinogénesis/patología , Ácido Desoxicólico/metabolismo , Mucosa Intestinal/patología , Neovascularización Patológica/patología , Adulto , Anciano , Animales , Apoptosis , Ácidos y Sales Biliares/análisis , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Dieta Alta en Grasa/efectos adversos , Transición Epitelial-Mesenquimal , Heces/química , Heces/microbiología , Femenino , Microbioma Gastrointestinal , Células HCT116 , Humanos , Mucosa Intestinal/microbiología , Masculino , Ratones , Persona de Mediana Edad , Neovascularización Patológica/etiología , Neovascularización Patológica/microbiología , Transducción de Señal , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
5.
Bioorg Med Chem Lett ; 78: 129041, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36332882

RESUMEN

Proteolysis Targeting Chimeras (PROTACs) based on multi-target inhibitors have been reported several times recently. The advantages of PROTACs technology and the synergistic mechanism of multi-target drugs endow this class of protein degraders with special research significance. Herein, twelve new PROTACs based on Sunitinib and VHL-ligand were synthesized and evaluated for their in vitro anticancer activities. Among them, PROTACs 5 (IC50 = 2.9 ± 1.5 µM) exhibited the most significant antiproliferative activity against HL-60 cells. Western blot results showed that PROTAC 5 reduced the protein levels of FLT-3 and c-KIT in HL-60 cells, and induced the degradation of FLT-3 via the ubiquitin-proteasome system. Moreover, PROTACs 5 and 6 reduced the protein levels of FLT-3 in K562 cells. These results suggest that PROTAC 5 has the potential for further research, especially in combination with small molecule kinase inhibitors to study multidrug resistance of tyrosine kinase inhibitors in cancer treatment.


Asunto(s)
Leucemia , Humanos , Sunitinib/farmacología , Proteolisis , Leucemia/tratamiento farmacológico , Células HL-60 , Complejo de la Endopetidasa Proteasomal
6.
Mol Cancer ; 20(1): 163, 2021 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-34895252

RESUMEN

Autophagy is a highly conserved catabolic process seen in eukaryotes and is essentially a lysosome-dependent protein degradation pathway. The dysregulation of autophagy is often associated with the pathogenesis of numerous types of cancers, and can not only promote the survival of cancer but also trigger the tumor cell death. During cancer development, the microbial community might predispose cells to tumorigenesis by promoting mucosal inflammation, causing systemic disorders, and may also regulate the immune response to cancer. The complex relationship between autophagy and microorganisms can protect the body by activating the immune system. In addition, autophagy and microorganisms can crosstalk with each other in multifaceted ways to influence various physiological and pathological responses involved in cancer progression. Various molecular mechanisms, correlating the microbiota disorders and autophagy activation, control the outcomes of protumor or antitumor responses, which depend on the cancer type, tumor microenvironment and disease stage. In this review, we mainly emphasize the leading role of autophagy during the interaction between pathogenic microorganisms and human cancers and investigate the various molecular mechanisms by which autophagy modulates such complicated biological processes. Moreover, we also highlight the possibility of curing cancers with multiple molecular agents targeting the microbiota/autophagy axis. Finally, we summarize the emerging clinical trials investigating the therapeutic potential of targeting either autophagy or microbiota as anticancer strategies, although the crosstalk between them has not been explored thoroughly.


Asunto(s)
Autofagia , Comunicación Celular , Interacciones Microbiota-Huesped , Microbiota , Neoplasias/etiología , Neoplasias/metabolismo , Animales , Biomarcadores , Transformación Celular Neoplásica , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Progresión de la Enfermedad , Susceptibilidad a Enfermedades , Humanos , Terapia Molecular Dirigida , Neoplasias/patología , Neoplasias/terapia , Resultado del Tratamiento
7.
J Cell Mol Med ; 24(4): 2648-2662, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31957197

RESUMEN

High-fat diet (HFD) is a well-known risk factor for gut microbiota dysbiosis and colorectal cancer (CRC). However, evidence relating HFD, gut microbiota and carcinogenesis is limited. Our study aimed to demonstrate that HFD-induced gut dysbiosis promoted intestinal adenoma-adenocarcinoma sequence. In clinical study, we found that HFD increased the incidence of advanced colorectal neoplasia (AN). The expression of monocyte chemoattractant protein 1 (MCP-1), CC chemokine receptor 2 (CCR2) and CD163 in CRC patients with HFD was significantly higher than that in CRC patients with normal diet. When it comes to the Apcmin/+ mice, HFD consumption could induce gut dysbiosis and promote intestinal carcinogenesis, accompanying with activation of MCP-1/CCR2 axis that recruited and polarized M2 tumour-associated macrophages. Interestingly, transfer of faecal microbiota from HFD-fed mice to another batch of Apcmin/+ mice in the absence of HFD could also enhance carcinogenesis without significant body weight gain and induced MCP-1/CCR2 axis activation. HFD-induced dysbiosis could also be transmitted. Meanwhile, antibiotics cocktail treatment was sufficient to inhibit HFD-induced carcinogenesis, indicating the vital role of dysbiosis in cancer development. Conclusively, these data indicated that HFD-induced dysbiosis accelerated intestinal adenoma-adenocarcinoma sequence through activation of MCP-1/CCR2 axis, which would provide new insight into better understanding of the mechanisms and prevention for HFD-related CRC.


Asunto(s)
Adenocarcinoma/metabolismo , Adenoma/metabolismo , Quimiocina CCL2/metabolismo , Neoplasias Colorrectales/metabolismo , Dieta Alta en Grasa/efectos adversos , Disbiosis/metabolismo , Macrófagos/metabolismo , Animales , Carcinogénesis/metabolismo , Femenino , Microbioma Gastrointestinal/fisiología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Estudios Retrospectivos
8.
Int J Cancer ; 146(7): 1780-1790, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31291465

RESUMEN

The prevalence of colorectal cancer (CRC) has markedly increased worldwide in the last decade. Alterations of bile acid metabolism and gut microbiota have been reported to play vital roles in intestinal carcinogenesis. About trillions of bacteria have inhabited in the human gut and maintained the balance of host metabolism. Bile acids are one of numerous metabolites that are synthesized in the liver and further metabolized by the gut microbiota, and are essential in maintaining the normal gut microbiota and lipid digestion. Multiple receptors such as FXR, GPBAR1, PXR, CAR and VDR act as sensors of bile acids have been reported. In this review, we mainly discussed interplay between bile acid metabolism and gut microbiota in intestinal carcinogenesis. We then summarized the critical role of bile acids receptors involving in CRC, and also addressed the rationale of multiple interventions for CRC management by regulating bile acids-microbiota axis such as probiotics, metformin, ursodeoxycholic acid and fecal microbiota transplantation. Thus, by targeting the bile acids-microbiota axis may provide novel therapeutic modalities in CRC prevention and treatment.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Animales , Ácidos y Sales Biliares/metabolismo , Terapia Biológica , Biomarcadores , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/terapia , Disbiosis , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Mucosa Intestinal/patología , Redes y Vías Metabólicas/efectos de los fármacos , Terapia Molecular Dirigida , Unión Proteica , Receptores Citoplasmáticos y Nucleares/metabolismo
9.
Lipids Health Dis ; 19(1): 95, 2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32430006

RESUMEN

BACKGROUND: The prevalence of hypertension in young women is lower than that in age-matched men while the prevalence of hypertension in women is significantly increased after the age of 50 (menopause) and is greater than that in men. It is already known that sphingosine-1-phosphate (S1P) and ceramide regulate vascular tone with opposing effects. This study aimed to explore the effects of ovariectomy and estrogen supplementation on the ceramide/S1P rheostat of the aorta in rats, and to explore a potential mechanism for perimenopausal hypertension and a brand-new target for menopausal hormone therapy to protect vessels. METHODS: In total, 30 female adult SD rats were randomly divided into three groups: The sham operation group (SHAM), ovariectomy group (OVX) and ovariectomy plus estrogen group (OVX + E). After 4 weeks of treatment, the blood pressure (BP) of the rats was monitored by a noninvasive system; the sphingolipid content (e.g., ceramide and S1P) was detected by liquid chromatography-mass spectrometry (LC-MS); the expression of the key enzymes involved in ceramide anabolism and catabolism was measured by real-time fluorescence quantitative polymerase chain reaction (qPCR); and the expression of key enzymes and proteins in the sphingosine kinase 1/2 (SphK1/2)-S1P-S1P receptor 1/2/3 (S1P1/2/3) signaling pathway was detected by qPCR and western blotting. RESULTS: In the OVX group compared with the SHAM group, the systolic BP (SBP), diastolic BP (DBP) and pulse pressure (PP) increased significantly, especially the SBP and PP (P < 0.001). For aortic ceramide metabolism, the mRNA level of key enzymes involved in anabolism and catabolism decreased in parallel 2-3 times, while the contents of total ceramide and certain long-chain subtypes increased significantly (P < 0.05). As for the S1P signaling pathway, SphK1/2, the key enzymes involved in S1P synthesis, decreased significantly, and the content of S1P decreased accordingly (P < 0.01). The S1P receptors showed various trends: S1P1 was significantly down-regulated, S1P2 was significantly up-regulated, and S1P3 showed no significant difference. No significant difference existed between the SHAM and OVX + E groups for most of the above parameters (P > 0.05). CONCLUSIONS: Ovariectomy resulted in the imbalance of the aortic ceramide/S1P rheostat in rats, which may be a potential mechanism underlying the increase in SBP and PP among perimenopausal women. Besides, the ceramide/S1P rheostat may be a novel mechanism by which estrogen protects vessels.


Asunto(s)
Aorta/metabolismo , Ceramidas/metabolismo , Estrógenos/uso terapéutico , Hipertensión/prevención & control , Lisofosfolípidos/metabolismo , Posmenopausia/efectos de los fármacos , Esfingosina/análogos & derivados , Animales , Aorta/química , Ceramidas/análisis , Estrógenos/farmacología , Femenino , Hipertensión/tratamiento farmacológico , Hipertensión/etiología , Hipertensión/metabolismo , Lisofosfolípidos/análisis , Modelos Animales , Ovariectomía , Ratas , Ratas Sprague-Dawley , Esfingosina/análisis , Esfingosina/metabolismo
10.
Chembiochem ; 20(9): 1133-1138, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30618116

RESUMEN

Histone demethylases play a critical role in mammalian gene expression by removing methyl groups from lysine residues in degree- and site-specific manner. To specifically interrogate members and isoforms of this class of enzymes, we have developed demethylase variants with an expanded active site. The mutant enzymes are capable of performing lysine demethylation with wild-type proficiency, but are sensitive to inhibition by cofactor-competitive molecules embellished with a complementary steric "bump". The selected inhibitors show more than 20-fold selectivity over the wild-type demethylase, thus overcoming issues typical to pharmacological and genetic approaches. The mutant-inhibitor pairs are shown to act on a physiologically relevant full-length substrate. By engineering a conserved amino acid to achieve member-specific perturbation, this study provides a general approach for studying histone demethylases in diverse cellular processes.


Asunto(s)
Inhibidores Enzimáticos/química , Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Aminoácidos/química , Biocatálisis , Dominio Catalítico/genética , Desmetilación , Histonas/química , Humanos , Histona Demetilasas con Dominio de Jumonji/química , Histona Demetilasas con Dominio de Jumonji/genética , Estructura Molecular , Mutación , Oxalatos/química , Ingeniería de Proteínas/métodos , Especificidad por Sustrato
11.
Mol Carcinog ; 58(7): 1155-1167, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30828892

RESUMEN

The gut microbiota and the bile acid pool play pivotal roles in maintaining intestinal homeostasis. Bile acids are produced in the liver from cholesterol and metabolized in the intestine by the gut microbiota. Gut dysbiosis has been reported to be associated with colorectal cancer. However, the interplay between bile acid metabolism and the gut microbiota during intestinal carcinogenesis remains unclear. In the present study, we investigated the potential roles of bile acids and the gut microbiota in the cholic acid (CA; a primary bile acid)-induced intestinal adenoma-adenocarcinoma sequence. Apc min/+ mice, which spontaneously develop intestinal adenomas, were fed a diet supplemented with 0.4% CA for 12 weeks. Mice that were fed a normal diet were regarded as untreated controls. In CA-treated Apc min/+ mice, the composition of the gut microbiota was significantly altered, and CA was efficiently transformed into deoxycholic acid (a secondary bile acid) by the bacterial 7α-dehydroxylation reaction. The intestinal adenoma-adenocarcinoma sequence was observed in CA-treated Apc min/+ mice and was accompanied by an impaired intestinal barrier function and IL-6/STAT3-related low-grade inflammation. More importantly, microbiota depletion using an antibiotic cocktail globally compromised CA-induced intestinal carcinogenesis, suggesting a leading role for the microbiota during this process. Overall, our data suggested that the crosstalk between bile acids and the gut microbiota mediated intestinal carcinogenesis, which might provide novel therapeutic strategies against intestinal tumor development.


Asunto(s)
Adenocarcinoma/patología , Adenoma/patología , Carcinogénesis/patología , Ácido Cólico/metabolismo , Neoplasias Colorrectales/patología , Microbioma Gastrointestinal/fisiología , Adenocarcinoma/microbiología , Adenoma/microbiología , Animales , Antibacterianos/farmacología , Ácidos y Sales Biliares/metabolismo , Neoplasias Colorrectales/microbiología , Suplementos Dietéticos , Disbiosis/patología , Femenino , Intestinos/microbiología , Intestinos/patología , Ratones , Ratones Transgénicos
12.
Chemistry ; 25(51): 11842-11846, 2019 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-31338914

RESUMEN

Alterations in Zn2+ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn2+ is an area of active investigation. Herein, enriched [1-13 C]cysteine and [1-13 C2 ]iminodiacetic acid were developed as Zn2+ -specific imaging probes using hyperpolarized 13 C magnetic resonance spectroscopy. [1-13 C]cysteine was used to accurately quantify Zn2+ in complex biological mixtures. These sensors can be employed to detect Zn2+ via imaging mechanisms including changes in 13 C chemical shift, resonance linewidth, or T1 .

13.
Mol Pharm ; 16(9): 3831-3841, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31381351

RESUMEN

Boron neutron capture therapy (BNCT) is a therapeutic modality which has been used for the treatment of cancers, including brain and head and neck tumors. For effective treatment via BNCT, efficient and selective delivery of a high boron dose to cancer cells is needed. Prostate-specific membrane antigen (PSMA) is a target for prostate cancer imaging and drug delivery. In this study, we conjugated boronic acid or carborane functional groups to a well-established PSMA inhibitor scaffold to deliver boron to prostate cancer cells and prostate tumor xenograft models. Eight boron-containing PSMA inhibitors were synthesized. All of these compounds showed a strong binding affinity to PSMA in a competition radioligand binding assay (IC50 from 555.7 to 20.3 nM). Three selected compounds 1a, 1d, and 1f were administered to mice, and their in vivo blocking of 68Ga-PSMA-11 uptake was demonstrated through a positron emission tomography (PET) imaging and biodistribution experiment. Biodistribution analysis demonstrated boron uptake of 4-7 µg/g in 22Rv1 prostate xenograft tumors and similar tumor/muscle ratios compared to the ratio for the most commonly used BNCT compound, 4-borono-l-phenylalanine (BPA). Taken together, these data suggest a potential role for PSMA targeted BNCT agents in prostate cancer therapy following suitable optimization.


Asunto(s)
Antígenos de Superficie/metabolismo , Terapia por Captura de Neutrón de Boro/métodos , Ácidos Borónicos/química , Ácidos Borónicos/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Glutamato Carboxipeptidasa II/antagonistas & inhibidores , Glutamato Carboxipeptidasa II/metabolismo , Neoplasias de la Próstata/radioterapia , Animales , Compuestos de Boro/química , Compuestos de Boro/farmacocinética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ácido Edético/análogos & derivados , Ácido Edético/farmacocinética , Isótopos de Galio , Radioisótopos de Galio , Humanos , Concentración 50 Inhibidora , Ligandos , Masculino , Ratones , Ratones Desnudos , Oligopéptidos/farmacocinética , Fenilalanina/análogos & derivados , Fenilalanina/química , Fenilalanina/farmacocinética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata/patología , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/farmacocinética , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Postgrad Med J ; 95(1122): 187-192, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30926717

RESUMEN

AIM: Patients with small serrated adenomas (SAs) (<10 mm) often undergo surveillance colonoscopy before the routine recommended time. We aimed to determine the appropriate surveillance intervals following polypectomy of small SAs for symptomatic patients. METHOD: We retrospectively reviewed the data of 638 patients, including 122 cases and 516 controls. Subjects in the case group had small SAs at baseline colonoscopy, including sessile SA/polyps and traditional SAs, while subjects in the control group had negative findings. All patients underwent at least one surveillance colonoscopy during the following 5 years. RESULTS: There was no significant difference in the incidence rate of advanced neoplasia between the two groups over a 5-year duration (3.6% vs 2.6%, p=0.455). Moreover, both groups also showed a low prevalence of SA formation over 1-5 years (3.6% vs 1.0%, p=0.145). Patients with baseline SA tended to undergo the first surveillance colonoscopy earlier than those without adenoma (≤1 year vs 1 to ≤3 years). Seventy-one (11.1%) of the total included subjects underwent inadequate initial colonoscopy, and 30 (42.3%) underwent early surveillance of adenoma formation within 1 year. Patients with a family history of colorectal cancer (OR 4.69, 95% CI 1.48 to 14.71, p=0.017) or inadequate baseline colonoscopy (OR 3.17, 95% CI 1.202 to 8.409, p=0.035) were at a higher risk of metachronous adenoma formation during the surveillance period. CONCLUSION: Patients with small SAs at baseline gain little benefit from follow-up of colonoscopy within 5 years after complete polypectomy.


Asunto(s)
Adenoma/patología , Adenoma/cirugía , Colonoscopía , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Biopsia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
15.
J Cell Mol Med ; 22(9): 4263-4273, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29956475

RESUMEN

High fat diet is implicated in the elevated deoxycholic acid (DCA) in the intestine and correlated with increased colon cancer risk. However, the potential mechanisms of intestinal carcinogenesis by DCA remain unclarified. Here, we investigated the carcinogenic effects and mechanisms of DCA using the intestinal tumour cells and Apcmin/+ mice model. We found that DCA could activate epidermal growth factor receptor (EGFR) and promote the release of EGFR ligand amphiregulin (AREG), but not HB-EGF or TGF-α in intestinal tumour cells. Moreover, ADAM-17 was required in DCA-induced promotion of shedding of AREG and activation of EGFR/Akt signalling pathway. DCA significantly increased the multiplicity of intestinal tumours and accelerated adenoma-carcinoma sequence in Apcmin/+ mice. ADAM-17/EGFR signalling axis was also activated in intestinal tumours of DCA-treated Apcmin/+ mice, whereas no significant change occurred in tumour adjacent tissues after DCA exposure. Conclusively, DCA activated EGFR and promoted intestinal carcinogenesis by ADAM17-dependent ligand release.


Asunto(s)
Proteína ADAM17/genética , Adenoma/genética , Anfirregulina/genética , Ácido Desoxicólico/administración & dosificación , Receptores ErbB/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Intestinales/genética , Proteína ADAM17/metabolismo , Adenoma/inducido químicamente , Adenoma/metabolismo , Adenoma/patología , Proteína de la Poliposis Adenomatosa del Colon/deficiencia , Proteína de la Poliposis Adenomatosa del Colon/genética , Anfirregulina/metabolismo , Animales , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Línea Celular Tumoral , Células Epiteliales/metabolismo , Células Epiteliales/patología , Receptores ErbB/metabolismo , Células HCT116 , Humanos , Neoplasias Intestinales/inducido químicamente , Neoplasias Intestinales/metabolismo , Neoplasias Intestinales/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Unión Proteica , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
16.
J Am Chem Soc ; 140(32): 10263-10269, 2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-30028600

RESUMEN

Ten-eleven translocation (TET) enzymes employ O2, earth-abundant iron, and 2-ketoglutarate (2KG) to perform iterative C-H oxidation of 5-methylcytosine in DNA to control expression of the mammalian genome. Given that more than 60 such C-H oxygenases are present in humans, determining context-dependent functions of each of these enzymes is a pivotal challenge. In an effort to tackle the problem, we developed analogue-sensitive TET enzymes to perturb the activity of a specific member. We rationally engineered the TET2-2KG interface to develop TET2 variants with an expanded active site that can be specifically inhibited by the N-oxalylglycine (NOG) derivatives carrying a complementary steric "bump". Herein, we describe the identification and engineering of a bulky gatekeeper residue for TET proteins, characterize the orthogonal mutant-inhibitor pairs, and show generality of the approach. Employing cell-permeable NOG analogues, we show that the TET2 mutant can be specifically inhibited to conditionally modulate cytosine methylation in chromosomal DNA in intact human cells. Finally, we demonstrate application of the orthogonal mutant-inhibitor pair to probe transcriptional activity of a specific TET member in cells. Our work provides a general platform for developing analogue-sensitive 2KG-dependent oxygenases to unravel their functions in diverse signaling processes.


Asunto(s)
Oxigenasas de Función Mixta/metabolismo , Secuencia de Aminoácidos , Animales , Metilación de ADN , Células HEK293 , Humanos , Ligandos , Oxigenasas de Función Mixta/genética , Conformación Proteica , Ingeniería de Proteínas
17.
Mol Pharm ; 15(9): 3860-3870, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30036479

RESUMEN

Nonalcoholic fatty liver disease (NAFLD), as a common chronic liver disorder, is prevalent in the world. Recent evidence demonstrates that the "gut-liver axis" is related well to the progression of NAFLD, which regards gut microbiota and the intestinal barrier as two critical factors correlated with NAFLD. Diammonium glycyrrhizinate (DG), a compound of the natural bioactive pentacyclic triterpenoid glycoside, is the main component of licorice root extracts. The anti-inflammatory and liver protection effects of DG have already been reported, but to date, the mechanism has not been fully elucidated. In this research, we observed that DG reduced body weight, liver steatosis, as well as hepatic inflammation in NAFLD model mice induced by a high-fat diet. Illumina sequencing of the 16S rRNA revealed that DG intervention notably altered the composition of the gut microbiota in NAFLD mice. The richness of gut microbiota was significantly increased by DG. Specifically, DG reduced the Firmicutes-to- Bacteroidetes ratio and the endotoxin-producing bacteria such as Desulfovibrio and elevated the abundance of probiotics such as Proteobacteria and Lactobacillus. DG could augment the levels of short-chain fatty acid (SCFA)-producing bacteria such as Ruminococcaceae and Lachnospiraceae and promote SCFA production. In addition, DG supplementation dramatically alleviated the intestinal low-grade inflammation. Meanwhile, DG improved the expression of tight junction proteins, the goblet cell number, and mucin secretion and sequentially enhanced the function of intestinal barrier. Collectively, the prevention of NAFLD by DG might be mediated by modulating gut microbiota and restoring the intestinal barrier.


Asunto(s)
Antiinflamatorios/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Ácido Glicirrínico/farmacología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Inmunohistoquímica , Intestinos/efectos de los fármacos , Intestinos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
18.
Mediators Inflamm ; 2018: 1562010, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30498394

RESUMEN

Inflammatory bowel disease (IBD), characterized by sustained inflammation, is a latent risk factor of colon tumorigenesis. Silibinin has been reported to be anti-inflammatory and antineoplastic, but its efficacy on colitis-associated cancer (CAC) has not been reported. Interlukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) is the key signaling pathway involved in CAC. We evaluated the chemopreventive effect of silibinin on a CAC mouse model and determined its impact on IL-6/STAT3 signaling. Intestinal tumor cells (IMCE and HCT-116 cell lines) were also treated by graded concentration of silibinin, and cellular viability was determined. Silibinin (750 mg/kg/day) was administered to an azoxymethane/dextran sulfate sodium (AOM/DSS) C57BL/6 mouse model for 10 weeks by gavage. Body weight, colon length, and the amount and diameter of colon tumors were documented, respectively. Specimens were subjected to H&E staining for colitis and tumor scoring, immunohistochemical staining and terminal deoxynucleotidyl transferase dUTP nick end labeling for proliferation assessment, and immunofluorescent staining for intestinal mucosa barrier assessment. Production of inflammatory cytokines was determined by real-time PCR. IL-6/STAT3 pathway activation was evaluated through immunohistochemical staining and western blot. In the current study, silibinin significantly inhibited the viability of intestinal tumor cells. The production of inflammatory cytokines and the phosphorylation of STAT3 were both inhibited in intestinal tumor cells. Meanwhile, silibinin decreased the amount and size of tumors in AOM/DSS mice. Colitis and tumor scores were decreased accompanying with inhibition of colonic tumor cell proliferation and promotion of cellular apoptosis. Additionally, silibinin could reduce the production of inflammatory cytokines and attenuate the impairment of colonic mucosal barrier. Furthermore, STAT3 phosphorylation was significantly suppressed by silibinin. In conclusion, silibinin could protect against colitis-associated tumorigenesis in mice via inhibiting IL-6/STAT3, which showed promising chemopreventive potential of CAC.


Asunto(s)
Colitis/complicaciones , Neoplasias del Colon/etiología , Neoplasias del Colon/metabolismo , Interleucina-6/metabolismo , Factor de Transcripción STAT3/metabolismo , Silibina/uso terapéutico , Animales , Azoximetano/toxicidad , Western Blotting , Colitis/inducido químicamente , Sulfato de Dextran/toxicidad , Femenino , Células HCT116 , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
19.
Int J Cancer ; 140(11): 2545-2556, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28187526

RESUMEN

The gut microbiota plays an important role in maintaining intestinal homeostasis. Dysbiosis is associated with intestinal tumorigenesis. Deoxycholic acid (DCA), a secondary bile acid increased by a western diet, correlates with intestinal carcinogenesis. However, evidence relating bile acids, intestinal microbiota and tumorigenesis are limited. In our study, we investigated the effect of DCA on induction of intestinal dysbiosis and its roles in intestinal carcinogenesis. Alteration of the composition of the intestinal microbiota was induced in DCA-treated APCmin/+ mice, which was accompanied by impaired intestinal barrier, gut low grade inflammation and tumor progression. The transfer of fecal microbiota from DCA-treated mice to another group of Apcmin/+ mice increased tumor multiplicity, induced inflammation and recruited M2 phenotype tumor-associated macrophages. Importantly, the fecal microbiota transplantation activated the tumor-associated Wnt/ß-catenin signaling pathway. Moreover, microbiota depletion by a cocktail of antibiotics was sufficient to block DCA-induced intestinal carcinogenesis, further suggesting the role of dysbiosis in tumor development. Our study demonstrated that alteration of the microbial community induced by DCA promoted intestinal carcinogenesis.


Asunto(s)
Ácidos y Sales Biliares/efectos adversos , Carcinogénesis/inducido químicamente , Disbiosis/inducido químicamente , Intestinos/patología , Animales , Carcinogénesis/patología , Ácido Desoxicólico/efectos adversos , Disbiosis/microbiología , Disbiosis/patología , Heces/microbiología , Inflamación/microbiología , Inflamación/patología , Intestinos/microbiología , Ratones , Ratones Endogámicos C57BL , Microbiota/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo
20.
World J Surg Oncol ; 14(1): 172, 2016 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-27352960

RESUMEN

BACKGROUND: Acinar cell carcinoma (ACC) is a relatively rare pancreatic neoplasm with poorly defined prognosis. This study aimed to investigate this rare pancreatic neoplasm through comparing patients with ACC to pancreatic ductal cell adenocarcinoma (DCA). METHODS: Tianjin Medical University Cancer Institute and Hospital pathology database was reviewed from 1995 to 2015, and 19 patients with pathologically confirmed ACC were enrolled while 19 conventional DCA patients assigned randomly as control. Retrospective review and follow-up were performed for each patient. Regression methods were used to identify differences between ACC and DCA. RESULTS: In our study, most patients suffered from abdominal or back pain, and no lipase hypersecretion syndrome was observed. For ACC, resected cases had better survival than those without resection, and earlier staging was related to longer survival. Resection with postoperative adjuvant therapy had a better outcome than surgery alone. Twelve cases developed recurrence. Compared to DCA, ACC had earlier staging and better survival. The overall 1-, 2-, and 5-year survival rates for patients with ACC were 73.7, 26.3, and 5 %, respectively. CONCLUSIONS: ACC carries a better prognosis than DCA and a similarly high recurrence rate, while surgical resection proved the best first-line approach for it. A well-planned neoadjuvant or adjuvant chemoradiotherapy indeed benefit the patients with ACC.


Asunto(s)
Carcinoma de Células Acinares/cirugía , Carcinoma Ductal Pancreático/cirugía , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Acinares/secundario , Carcinoma Ductal Pancreático/secundario , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
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