Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Int J Mol Sci ; 24(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37569713

RESUMEN

The phosphatidylinositol (PI3K)/AKT/mTOR axis represents an important therapeutic target to treat human cancers. A well-described downstream target of the PI3K pathway is the forkhead box O (FOXO) transcription factor family. FOXOs have been implicated in many cellular responses, including drug-induced resistance in cancer cells. However, FOXO-dependent acute phase resistance mediated by pictilisib, a potent small molecule PI3K inhibitor (PI3Ki), has not been studied. Here, we report that pictilisib-induced adaptive resistance is regulated by the FOXO-dependent rebound activity of receptor tyrosine kinases (RTKs) in mucinous colorectal adenocarcinoma (MCA) cells. The resistance mediated by PI3K inhibition involves the nuclear localization of FOXO and the altered expression of RTKs, including ErbB2, ErbB3, EphA7, EphA10, IR, and IGF-R1 in MCA cells. Further, in the presence of FOXO siRNA, the pictilisib-induced feedback activation of RTK regulators (pERK and pAKT) was altered in MCA cells. Interestingly, the combinational treatment of pictilisib (Pi3Ki) and FOXO1i (AS1842856) synergistically reduced MCA cell viability and increased apoptosis. These results demonstrate that pictilisib used as a single agent induces acute resistance, partly through FOXO1 inhibition. Therefore, overcoming PI3Ki single-agent adaptive resistance by rational design of FOXO1 and PI3K inhibitor combinations could significantly enhance the therapeutic efficacy of PI3K-targeting drugs in MCA cells.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Tirosina Quinasas Receptoras , Factores de Transcripción Forkhead/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Tirosina , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína Forkhead Box O1/genética
2.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37108697

RESUMEN

SARS-CoV-2 severity predictions are feasible, though individual susceptibility is not. The latter prediction allows for planning vaccination strategies and the quarantine of vulnerable targets. Ironically, the innate immune response (InImS) is both an antiviral defense and the potential cause of adverse immune outcomes. The competition for iron has been recognized between both the immune system and invading pathogens and expressed in a ratio of ferritin divided by p87 (as defined by the Adnab-9 ELISA stool-binding optical density, minus the background), known as the FERAD ratio. Associations with the FERAD ratio may allow predictive modeling for the susceptibility and severity of disease. We evaluated other potential COVID-19 biomarkers prospectively. Patients with PCR+ COVID-19 tests (Group 1; n = 28) were compared to three other groups. In Group 2 (n = 36), and 13 patients displayed COVID-19-like symptoms but had negative PCR or negative antibody tests. Group 3 (n = 90) had no symptoms and were negative when routinely PCR-tested before medical procedures. Group 4 (n = 2129) comprised a pool of patients who had stool tests and symptoms, but their COVID-19 diagnoses were unknown; therefore, they were chosen to represent the general population. Twenty percent of the Group 4 patients (n = 432) had sufficient data to calculate their FERAD ratios, which were inversely correlated with the risk of COVID-19 in the future. In a case report of a neonate, we studied three biomarkers implicated in COVID-19, including p87, Src (cellular-p60-sarcoma antigen), and Abl (ABL-proto-oncogene 2). The InImS of the first two were positively correlated. An inverse correlation was found between ferritin and lysozyme in serum (p < 0.05), suggesting that iron could have impaired an important innate immune system anti-viral effector and could partially explain future COVID-19 susceptibility.


Asunto(s)
COVID-19 , Humanos , Recién Nacido , Biomarcadores de Tumor , COVID-19/epidemiología , Ferritinas , Sistema Inmunológico , Hierro , Pandemias , Estudios Prospectivos , SARS-CoV-2
3.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139086

RESUMEN

Given the need to improve the sensitivity of non-invasive methods to detect colorectal neoplasia, particularly adenomas, we compared a fecal test using a monoclonal antibody (Mab) raised against constituents of colonic adenomas designated Adnab-9 (Adenoma Antibody 9), recognizing an N-linked 87 kDa glycoprotein, to gFOBT, which is shown to reduce CRC mortality. p87 immunohistochemistry testing is significantly more sensitive (OR 3.64[CI 2.37-5.58]) than gFOBT (guaiac-based fecal occult blood test) for adenomas (<3 in number), advanced adenomas (OR 4.21[CI 2.47-7.15]), or a combination of the two (OR 3.35[CI 2.47-4.53]). p87 immunohistochemistry shows regional Paneth cell (PC) expression mainly in the right-sided colon and is significantly reduced in the ceca of African Americans (p < 0.0001). In a subset of patients, we obtained other body fluids such as urine, colonic effluent, and saliva. Urine tests (organ-specific neoantigen) showed a significant difference for advanced adenomas (p < 0.047). We conclude that fecal p87 testing is more sensitive than gFOBT and Adnab-9 and could be used to better direct the colonoscopy screening effort.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Humanos , Guayaco , Sangre Oculta , Tamizaje Masivo/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/prevención & control , Colonoscopía/métodos , Adenoma/diagnóstico , Sensibilidad y Especificidad , Detección Precoz del Cáncer/métodos
4.
J Immunol ; 198(10): 3775-3789, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28483986

RESUMEN

Scavenger receptors constitute a large family of proteins that are structurally diverse and participate in a wide range of biological functions. These receptors are expressed predominantly by myeloid cells and recognize a diverse variety of ligands including endogenous and modified host-derived molecules and microbial pathogens. There are currently eight classes of scavenger receptors, many of which have multiple names, leading to inconsistencies and confusion in the literature. To address this problem, a workshop was organized by the United States National Institute of Allergy and Infectious Diseases, National Institutes of Health, to help develop a clear definition of scavenger receptors and a standardized nomenclature based on that definition. Fifteen experts in the scavenger receptor field attended the workshop and, after extensive discussion, reached a consensus regarding the definition of scavenger receptors and a proposed scavenger receptor nomenclature. Scavenger receptors were defined as cell surface receptors that typically bind multiple ligands and promote the removal of nonself or altered-self targets. They often function by mechanisms that include endocytosis, phagocytosis, adhesion, and signaling that ultimately lead to the elimination of degraded or harmful substances. Based on this definition, nomenclature and classification of these receptors into 10 classes were proposed. This classification was discussed at three national meetings and input from participants at these meetings was requested. The following manuscript is a consensus statement that combines the recommendations of the initial workshop and incorporates the input received from the participants at the three national meetings.


Asunto(s)
Receptores Depuradores/clasificación , Receptores Depuradores/fisiología , Animales , Endocitosis , Humanos , Ligandos , Ratones , National Institute of Allergy and Infectious Diseases (U.S.)/normas , Fagocitosis , Receptores Inmunológicos/fisiología , Receptores Depuradores de Clase A/fisiología , Transducción de Señal , Terminología como Asunto , Estados Unidos
6.
Am J Physiol Gastrointest Liver Physiol ; 310(11): G930-40, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27056722

RESUMEN

Alcohol consumption exacerbates hepatitis C virus (HCV) pathogenesis and promotes disease progression, although the mechanisms are not quite clear. We have previously observed that acetaldehyde (Ach) continuously produced by the acetaldehyde-generating system (AGS), temporarily enhanced HCV RNA levels, followed by a decrease to normal or lower levels, which corresponded to apoptosis induction. Here, we studied whether Ach-induced apoptosis caused depletion of HCV-infected cells and what role apoptotic bodies (AB) play in HCV-alcohol crosstalk. In liver cells exposed to AGS, we observed the induction of miR-122 and miR-34a. As miR-34a has been associated with apoptotic signaling and miR-122 with HCV replication, these findings may suggest that cells with intensive viral replication undergo apoptosis. Furthermore, when AGS-induced apoptosis was blocked by a pan-caspase inhibitor, the expression of HCV RNA was not changed. AB from HCV-infected cells contained HCV core protein and the assembled HCV particle that infect intact hepatocytes, thereby promoting the spread of infection. In addition, AB are captured by macrophages to switch their cytokine profile to the proinflammatory one. Macrophages exposed to HCV(+) AB expressed more IL-1ß, IL-18, IL-6, and IL-10 mRNAs compared with those exposed to HCV(-) AB. The generation of AB from AGS-treated HCV-infected cells even enhanced the induction of aforementioned cytokines. We conclude that HCV and alcohol metabolites trigger the formation of AB containing HCV particles. The consequent spread of HCV to neighboring hepatocytes via infected AB, as well as the induction of liver inflammation by AB-mediated macrophage activation potentially exacerbate the HCV infection course by alcohol and worsen disease progression.


Asunto(s)
Acetaldehído/metabolismo , Apoptosis , Hepacivirus/fisiología , Hepatocitos/metabolismo , Replicación Viral , Línea Celular , Células Cultivadas , Hepacivirus/patogenicidad , Hepatocitos/virología , Humanos , Interleucinas/genética , Interleucinas/metabolismo , Macrófagos/metabolismo , Macrófagos/virología , MicroARNs/genética , MicroARNs/metabolismo , ARN Viral/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo
7.
Alcohol Clin Exp Res ; 40(11): 2312-2319, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27581622

RESUMEN

BACKGROUND: Alcohol-induced reduction in the hepatocellular S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio impairs the activities of many SAM-dependent methyltransferases. These impairments ultimately lead to the generation of several hallmark features of alcoholic liver injury including steatosis. Guanidinoacetate methyltransferase (GAMT) is an important enzyme that catalyzes the final reaction in the creatine biosynthetic process. The liver is a major site for creatine synthesis which places a substantial methylation burden on this organ as GAMT-mediated reactions consume as much as 40% of all the SAM-derived methyl groups. We hypothesized that dietary creatine supplementation could potentially spare SAM, preserve the hepatocellular SAM:SAH ratio, and thereby prevent the development of alcoholic steatosis and other consequences of impaired methylation reactions. METHODS: For these studies, male Wistar rats were pair-fed the Lieber-DeCarli control or ethanol (EtOH) diet with or without 1% creatine supplementation. At the end of 4 to 5 weeks of feeding, relevant biochemical and histological analyses were performed. RESULTS: We observed that creatine supplementation neither prevented alcoholic steatosis nor attenuated the alcohol-induced impairments in proteasome activity. The lower hepatocellular SAM:SAH ratio seen in the EtOH-fed rats was also not normalized or SAM levels spared when these rats were fed the creatine-supplemented EtOH diet. However, a >10-fold increased level of creatine was observed in the liver, serum, and hearts of rats fed the creatine-supplemented diets. CONCLUSIONS: Overall, dietary creatine supplementation did not prevent alcoholic liver injury despite its known efficacy in preventing high-fat-diet-induced steatosis. Betaine, a promethylating agent that maintains the hepatocellular SAM:SAH, still remains our best option for treating alcoholic steatosis.


Asunto(s)
Creatina/uso terapéutico , Hígado Graso Alcohólico/prevención & control , Amidinotransferasas/metabolismo , Animales , Suplementos Dietéticos , Guanidinoacetato N-Metiltransferasa/metabolismo , Riñón/enzimología , Hígado/enzimología , Masculino , Miocardio/metabolismo , Ratas Wistar , S-Adenosilhomocisteína/metabolismo , S-Adenosilmetionina/metabolismo
8.
BMC Gastroenterol ; 16: 27, 2016 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-26924554

RESUMEN

BACKGROUND: Non-alcoholic and alcoholic fatty liver disease (NAFLD and AFLD, respectively) are major health problems, as patients with either condition can progress to hepatitis, fibrosis, and cirrhosis. Although histologically similar, key differences likely exist in these two models. For example, altered content of several vesicle trafficking proteins have been identified in AFLD, but their content in NAFLD is unknown. In this study, we compared select parameters in NAFLD and AFLD in a rat model. METHODS: We fed either Lieber- DeCarli liquid control or alcohol-containing (35 % as calories) diet (AFLD model) or lean or high-fat (12 or 60 % derived from fat, respectively) pellets (NAFLD model) for 8-10 weeks, n = 8 in each model. Serum, hepatocytes and liver tissue were analyzed. Liver injury markers were measured in serum, triglyceride content and endocytosis (binding and internalization of (125)I- asialoorosomucoid) was measured in isolated hepatocytes, and content of selected trafficking proteins (Rab3D, Rab7 and Rab18) were determined in whole liver tissue. RESULTS: Although liver injury markers and triglyceride content were similar in both models, binding and internalization of (125)I- asialoorosomucoid was significantly impaired in the hepatocytes from AFLD, but not NAFLD, animals. In addition, protein content of the asialoglycoprotein receptor (ASGPR) and three trafficking proteins, Rab3D, Rab7and Rab18, were significantly decreased after alcohol, but not high-fat feeding. Levels of protein carbonylation, amount of glutathione stores, and lipid peroxidation were similar irrespective of the insult to the livers that resulted in fatty liver. CONCLUSION: Impairments in protein trafficking in AFLD are likely a direct result of alcohol administration, and not a function of fatty liver.


Asunto(s)
Endocitosis/fisiología , Hígado Graso Alcohólico/metabolismo , Hepatocitos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , ARN Mensajero/metabolismo , Vesículas Transportadoras/metabolismo , Alanina Transaminasa/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Receptor de Asialoglicoproteína/genética , Receptor de Asialoglicoproteína/metabolismo , Ácidos y Sales Biliares/metabolismo , Western Blotting , Colesterol/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Etanol/toxicidad , Hígado Graso Alcohólico/etiología , Inmunohistoquímica , Proteínas de la Membrana/metabolismo , Perilipina-2 , Ratas , Albúmina Sérica/metabolismo , Solventes/toxicidad , Triglicéridos/metabolismo , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo , Proteínas de Unión al GTP rab3/genética , Proteínas de Unión al GTP rab3/metabolismo , Proteínas de Unión a GTP rab7
9.
Adv Exp Med Biol ; 815: 295-311, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25427914

RESUMEN

It is well established that alcohol consumption is related to the development of alcoholic liver disease. Additionally, it is appreciated that other major health issues are associated with alcohol abuse, including colorectal cancer (CRC) and its metastatic growth to the liver. Although a correlation exists between alcohol use and the development of diseases, the search continues for a better understanding of specific mechanisms. Concerning the role of alcohol in CRC liver metastases, recent research is aimed at characterizing the processing of carcinoembryonic antigen (CEA), a glycoprotein that is associated with and secreted by CRC cells. A positive correlation exists between serum CEA levels, liver metastasis, and alcohol consumption in CRC patients, although the mechanism is not understood. It is known that circulating CEA is processed primarily by the liver, first by nonparenchymal Kupffer cells (KCs) and secondarily, by hepatocytes via the asialoglycoprotein receptor (ASGPR). Since both KCs and hepatocytes are known to be significantly impacted by alcohol, it is hypothesized that alcohol-related effects to these liver cells will lead to altered CEA processing, including impaired asialo-CEA degradation, resulting in changes to the liver microenvironment and the metastatic potential of CRC cells. Also, it is predicted that CEA processing will affect cytokine production in the alcohol-injured liver, resulting in pro-metastatic changes such as enhanced adhesion molecule expression on the hepatic sinusoidal endothelium. This chapter examines the potential role that alcohol-induced liver cell impairments can have in the processing of CEA and associated mechanisms involved in CEA-related colorectal cancer liver metastasis.


Asunto(s)
Antígeno Carcinoembrionario/metabolismo , Neoplasias Colorrectales/patología , Etanol/toxicidad , Neoplasias Hepáticas/secundario , Hígado/efectos de los fármacos , Animales , Asialoglicoproteínas/metabolismo , Humanos , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/metabolismo
10.
Alcohol Clin Exp Res ; 38(2): 327-35, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24117505

RESUMEN

BACKGROUND: Alcoholic liver disease is manifested by the presence of fatty liver, primarily due to accumulation of hepatocellular lipid droplets (LDs). The presence of membrane-trafficking proteins (e.g., Rab GTPases) with LDs indicates that LDs may be involved in trafficking pathways known to be altered in ethanol (EtOH) damaged hepatocytes. As these Rab GTPases are crucial regulators of protein trafficking, we examined the effect EtOH administration has on hepatic Rab protein content and association with LDs. METHODS: Male Wistar rats were pair-fed Lieber-DeCarli diets for 5 to 8 weeks. Whole liver and isolated LD fractions were analyzed. Identification of LDs and associated Rab proteins was performed in frozen liver or paraffin-embedded sections followed by immunohistochemical analysis. RESULTS: Lipid accumulation was characterized by larger LD vacuoles and increased total triglyceride content in EtOH-fed rats. Rabs 1, 2, 3d, 5, 7, and 18 were analyzed in postnuclear supernatant (PNS) as well as LDs. All of the Rabs were found in the PNS, and Rabs 1, 2, 5, and 7 did not show alcohol-altered content, while Rab 3d content was reduced by over 80%, and Rab 18 also showed EtOH-induced reduction in content. Rab 3d was not found to associate with LDs, while all other Rabs were found in the LD fractions, and several showed an EtOH-related decrease (Rabs 2, 5, 7, 18). Immunohistochemical analysis revealed the enhanced content of a LD-associated protein, perilipin 2 (PLIN2) that was paralleled with an associated decrease of Rab 18 in EtOH-fed rat sections. CONCLUSIONS: Chronic EtOH feeding was associated with increased PLIN2 and altered Rab GTPase content in enriched LD fractions. Although mechanisms driving these changes are not established, further studies on intracellular protein trafficking and LD biology after alcohol administration will likely contribute to our understanding of fatty liver disease.


Asunto(s)
Depresores del Sistema Nervioso Central/química , Etanol/química , Metabolismo de los Lípidos/efectos de los fármacos , Lípidos/química , Solventes/química , Proteínas de Unión al GTP rab/química , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Western Blotting , Dieta , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Inmunohistoquímica , Hígado/citología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Tamaño de la Partícula , Perilipina-2 , Ratas , Ratas Wistar , Triglicéridos/metabolismo
11.
Biomolecules ; 14(9)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39334948

RESUMEN

The primary pre-neoplastic lesion of the lower esophagus in the vicinity of the gastroesophageal junction (GEJ) is any Barrett's esophageal lesions (BE), and esophageal neoplasia has increased in the US population with predispositions (Caucasian males, truncal obesity, age, and GERD). The responses to BE are endoscopic and screening cytologic programs with endoscopic ablation of various forms. The former have not been proven to be cost-effective and there are mixed results for eradication. A fresh approach is sorely needed. We prospectively followed 2229 mostly male veterans at high risk for colorectal cancer in a 27-year longitudinal long-term study, collecting data on colorectal neoplasia development and other preneoplastic lesions, including BE and spontaneous regression (SR). Another cross-sectional BE study at a similar time period investigated antigenic changes at the GEJ in both BE glandular and squamous mucosa immunohistochemistry and the role of inflammation. Ten of the prospective cohort (21.7%) experienced SR out of a total of forty-six BE patients. Significant differences between SR and stable BE were younger age (p < 0.007); lower platelet levels (p < 0.02); rectal p87 elevation in SR (p < 0.049); a reduced innate immune system (InImS) FEREFF ratio (ferritin: p87 colonic washings) (p < 0.04). Ancillary testing showed a broad range of neoplasia biomarkers. InImS markers may be susceptible to intervention using commonplace and safe medical interventions and encourage SR.


Asunto(s)
Esófago de Barrett , Neoplasias Esofágicas , Humanos , Masculino , Persona de Mediana Edad , Esófago de Barrett/patología , Esófago de Barrett/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo
12.
Exp Mol Pathol ; 95(3): 376-84, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24161955

RESUMEN

Excessive alcohol consumption presents considerable health risks in humans. A variety of morphologic and functional changes contribute to hepatic injury produced by heavy drinking. The present review summarizes the current knowledge of alcohol-induced liver disease and describes preclinical experimental approaches used to understand alcoholic liver disease (ALD), with a particular emphasis on impaired protein and lipid trafficking, disruption of proteolysis and autophagy, alterations in methionine metabolism and perturbations in metabolic signaling that cause dysfunctional gene expression and the eventual formation of aggresomal Mallory-Denk bodies (MDB) in liver cells. These changes eventually lead to some of the more severe hepatic impairments, including alcoholic hepatitis and fibrosis. Moreover the misuse of alcohol contributes to immune dysfunction and inadequate immune response to viral infections.


Asunto(s)
Modelos Animales de Enfermedad , Hepatopatías Alcohólicas/patología , Investigación Biomédica Traslacional , Animales , Humanos , Hepatopatías Alcohólicas/metabolismo
13.
Biology (Basel) ; 12(10)2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37886997

RESUMEN

Peroxisome-proliferator-activated receptor gamma (PPARγ) is a transcription factor with adipogenic, insulin-sensitizing, and antifibrotic properties. Strong PPARγ activators, such as the thiazolidinediones, can induce unwanted effects such as edema, weight gain, and bone loss, and therefore selective modulators of PPARγ are in development. We previously reported that one selective PPARγ modulator, SR1664, reduced toxin-induced hepatic fibrosis and the activation of hepatic stellate cells (HSCs), the main collagen-producing liver cell in fibrosis. In this study, we used a high fat and high carbohydrate (HFHC) model of hepatic steatosis and fibrosis to determine the effect of SR1664. Mice were placed on a standard chow or HFHC diet for 16 weeks, with SR1664 or control treatment for the final 4 weeks. SR1664 did not alter weight gain or fasting insulin or glucose levels. The size of lipid droplets in the HFHC group was reduced by SR1664, but there was no effect on total liver triglyceride levels. The degree of fibrosis was significantly reduced by SR1664 in mice on the HFHC diet, and this was accompanied by a decrease in activated HSC. In summary, SR1664 improved insulin sensitivity and reduced fibrosis in the HFHC diet, suggesting selective PPARγ modulation is effective in obesity-related liver fibrosis.

14.
Biology (Basel) ; 12(2)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36829534

RESUMEN

The consumption of alcohol has long been associated with the development of liver disease as well as cancers including colorectal cancer (CRC). Leading healthcare concerns include the prevalent use of alcohol and the high burden of CRC mortality. Many CRC deaths are attributed to the development of colorectal liver metastasis (CRLM) as the liver is the foremost site of CRC spread. However, an association has not been defined for the role of alcohol intake and related liver injury with the development of CRLM. Here, a mapping review of recent research was undertaken to evaluate the relationship between alcohol consumption and the risk of CRLM. The literature search revealed 14 articles meeting the inclusion criteria that included patient database analyses and preclinical studies. Most of the human data analyses found alcohol use independently associates with worse CRC outcomes. The preclinical evaluations identified several pathways involved in the alcohol-mediated promotion of CRLM burden and CRC cell metastatic behavior. The limited number of studies identified exposes a significant need for more prospective analyses to define the role of alcohol intake and advanced CRC as well as the translation of preclinical research to fully characterize targetable mechanisms for the generation of new therapeutic options.

15.
Hepatol Commun ; 7(4)2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36972397

RESUMEN

BACKGROUND: Chronic ethanol exposure leads to enhanced protein acetylation and acetaldehyde adduction. Of the multitude of proteins that are modified on ethanol administration, tubulin is among the best studied. However, an open question is whether these modifications are observed in patient samples. Both modifications have also been implicated in promoting alcohol-induced defects in protein trafficking, but whether they do so directly is also unanswered. METHODS AND RESULTS: We first confirmed that tubulin was hyperacetylated and acetaldehyde-adducted in the livers from ethanol-exposed individuals to a similar extent as observed in the livers from ethanol-fed animals and hepatic cells. Livers from individuals with nonalcohol-associated fatty liver showed modest increases in tubulin acetylation, whereas nonalcohol-associated fibrotic human and mouse livers showed virtually no tubulin modifications. We also asked whether tubulin acetylation or acetaldehyde adduction can directly explain the known alcohol-induced defects in protein trafficking. Acetylation was induced by overexpressing the α-tubulin-specific acetyltransferase, αTAT1, whereas adduction was induced by directly adding acetaldehyde to cells. Both αTAT1 overexpression and acetaldehyde treatment significantly impaired plus-end (secretion) and minus-end (transcytosis)-directed microtubule-dependent trafficking and clathrin-mediated endocytosis. Each modification led to similar levels of impairment as observed in ethanol-treated cells. The levels of impairment by either modification showed no dose dependence or no additive effects suggesting that substoichiometric tubulin modifications lead to altered protein trafficking and that lysines are not selectively modified. CONCLUSIONS: These results not only confirm that enhanced tubulin acetylation is observed in human livers but that it is most relevant to alcohol-induced injury. Because these tubulin modifications are associated with altered protein trafficking that alters proper hepatic function, we propose that changing the cellular acetylation levels or scavenging free aldehydes are feasible strategies for treating alcohol-associated liver disease.


Asunto(s)
Hepatopatías Alcohólicas , Tubulina (Proteína) , Ratones , Animales , Humanos , Tubulina (Proteína)/metabolismo , Etanol/farmacología , Hepatopatías Alcohólicas/metabolismo , Acetaldehído/metabolismo , Procesamiento Proteico-Postraduccional , Transporte de Proteínas
16.
Gastro Hep Adv ; 2(3): 362-369, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-39132647

RESUMEN

Background and Aims: It has been recently proposed to change the nomenclature of "chronic radiation proctitis" (CRP) to "radiation-associated vascular ectasia" on the basis that signs of inflammation are rarely observed. We herein present data supporting the idea that inflammation is a critical step that initiates the process that culminates in the characteristic changes of CRP. Methods: In support of inflammation in the pathogenesis of CRP, we review the pertinent literature and publish our new results, including the role of amifostine treatment and proinflammatory factors (p38 MAP kinase, VEGF, and CEACAM1). Results: Immunohistochemistry from anterior rectal wall biopsies obtained in a prospective pilot study demonstrates that expression of VEGF and the downstream vascular effector CEACAM1 were elevated before radiotherapy and declined with time. We also show that MAP Kinase p38 expression usually precede the radiation. Fibrosis scores increase from baseline at 9 and 18 months, while vascular scores decrease at 18 months. Conclusion: The proposed new nomenclature should be held in obeyance until more supportive data are presented. Possibly, the best way to view CRP is as a continuum that may take one of three forms, inflammation-predominant, vasculopathy-predominant, or mixed.

17.
Curr Oncol ; 30(9): 7950-7963, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37754493

RESUMEN

BACKGROUND: We evaluated the phenotype of sporadic gastric cancer based on HP status and binding of a tumor risk marker monoclonal, Adnab-9. METHODS: We compared a familial GC kindred with an extremely aggressive phenotype to HP-positive (HP+) and -negative (HP-) sporadic gastric adenocarcinoma (GC) patients in the same community to determine if similar phenotypes exist. This might facilitate gene discovery to understand the pathogenesis of aggressive GC phenotypes, particularly with publications implicating immune-related gene-based signatures, and the development of techniques to gauge the stance of the innate immune system (InImS), such as the FERAD ratio (blood ferritin:fecal Adnab-9 binding OD-background binding). Resection specimens for the sporadic and familial group were stained for HP and examined for intestinal metaplasia (IM) and immunostaining for Adnab-9. Familial kindred specimens were also tested for the E-cadherin mutation and APC (adenomatous polyposis coli). Survival was evaluated. RESULTS: Of 40 GC patients, 25% were HP+ with a greater proportion of intestinal metaplasia (IM) and gastric atrophy than the HP- group. The proband of the familial GC kindred, a 32-year-old mother with fatal GC, was survived by 13-year-old identical twins. Twin #1 was HP- with IM and Twin #2 was HP+. Both twins subsequently died of GC within two years. The twins did not have APC or E-cadherin mutations. The mean overall survival in the HP+ sporadic GC group was 2.47 ± 2.58 years and was 0.57 ± 0.60 years in the HP- group (p = 0.01). Survival in the kindred was 0.22 ± 0.24 years. Adnab-9 labeling was positive in fixed tissues of 50% of non-familial GC patients and in gastric tissue extract from Twin #2. The FERAD ratio was determined separately in six prospectively followed patient groups (n = 458) and was significantly lower in the gastric cancer patients (n = 10) and patients with stomach conditions predisposing them to GC (n = 214), compared to controls (n = 234 patients at increased risk for colorectal cancer but without cancer), suggesting a failure of the InImS. CONCLUSION: The HP+ sporadic GC group appears to proceed through a sequence of HP infection, IM and atrophy before cancer supervenes, and the HP- phenotype appear to omit this sequence. The familial cases may represent a subset with both features, but the natural history strongly resembles that of the HP- group. Two different paths of carcinogenesis may exist locally for sporadic GC. The InImS may also be implicated in prognosis. Identifying these patients will allow for treatment stratification and early diagnosis to improve GC survival.


Asunto(s)
Adenocarcinoma , Helicobacter pylori , Neoplasias Gástricas , Humanos , Adulto , Adolescente , Neoplasias Gástricas/genética , Adenocarcinoma/genética , Carcinogénesis , Atrofia , Cadherinas
18.
Pharmaceutics ; 14(3)2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35336043

RESUMEN

Alcohol-associated liver disease (AALD) is a major cause of liver disorders worldwide. Current treatment options are limited, especially for AALD-associated fibrosis. Promising approaches include RNA interference for miR-155 overexpression in Kupffer cells (KCs), as well as the use of CXCR4 antagonists that inhibit the activation of hepatic stellate cells (HSCs) through the CXCL12/CXCR4 axis. The development of dual-functioning nanoparticles for the effective delivery of antifibrotic RNA together with a CXCR4 inhibitor thus promises to improve the treatment of AALD fibrosis. In this study, cholesterol-modified polymeric CXCR4 inhibitor (Chol-PCX) was synthesized and used to encapsulate anti-miR-155 or non-coding (NC) miRNA in the form of Chol-PCX/miRNA nanoparticles. The results indicate that the nanoparticles induce a significant miR-155 silencing effect both in vitro and in vivo. Treatment with the Chol-PCX/anti-miR-155 particles in a model of moderate alcohol consumption with secondary liver insult resulted in a significant reduction in aminotransferase enzymes as well as collagen content in the liver parenchyma. Overall, our data support the use of Chol-PCX as a carrier for anti-miR-155 for the combined therapeutic inhibition of CXCR4 and miR-155 expression as a way to improve fibrotic damage in the liver.

19.
Alcohol Clin Exp Res ; 35(4): 717-25, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21223308

RESUMEN

BACKGROUND: Excessive alcohol consumption leads to the increased extracellular matrix deposition of cellular fibronectin (cFn) in the liver, which is also implicated as an initiating event in the fibrogenic process. We propose that cFn directly stimulates Kupffer cells (KCs), which are involved in the early response to tissue damage, to produce factors that enhance the progression of alcohol-induced liver injury toward inflammation and fibrosis. METHOD: KCs were isolated from rats fed a control or ethanol liquid diet for 4 to 6 weeks. The effect of exogenous cFn on KC viability and the secretion of the cytokines, TNF-α and IL-6, as well as of matrix remodeling factors, MMP-2 and TIMP-2, was determined after 20 hours of cell culture. RESULTS: For KCs from both control- and ethanol-fed rats, viability remained unaffected by treatment with cFn. TNF-α and IL-6 production were increased in KCs exposed to cFn, with cells treated with 1, 2.5, and 5 µg/ml cFn secreting significantly higher levels of both cytokines compared with untreated cells (p < 0.05). Chronic ethanol administration resulted in a significantly enhanced secretion of IL-6 by KCs regardless of treatment with cFn. When MMP-2 protein and activity levels were measured by western blot analysis and gelatin zymography, respectively, we found that cFn stimulated a dramatic increase in both cells from ethanol- and control-fed rats, with the KCs from ethanol animals being more responsive to cFn at higher concentrations (p < 0.05). Significantly higher levels of TIMP-2, which inhibits both the activation and activity of MMP-2, were secreted by KCs treated with 5 µg/ml cFn. Correspondingly, more pro-MMP-2 than active-MMP-2 was detected. CONCLUSION: Altogether, these results show that cFn stimulates KCs to produce factors that may enhance the promotion of tissue damage and that ethanol administration increases these responses.


Asunto(s)
Depresores del Sistema Nervioso Central/toxicidad , Etanol/toxicidad , Fibronectinas/fisiología , Inflamación/inducido químicamente , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/fisiología , Hígado/fisiopatología , Animales , Caspasa 3/metabolismo , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Depresores del Sistema Nervioso Central/metabolismo , Depresores del Sistema Nervioso Central/farmacología , Etanol/metabolismo , Etanol/farmacología , Matriz Extracelular/fisiología , Inflamación/fisiopatología , Interleucina-6/metabolismo , Macrófagos del Hígado/citología , Macrófagos del Hígado/patología , Hígado/citología , Masculino , Metaloproteinasa 2 de la Matriz , Ratas , Ratas Wistar , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Factor de Necrosis Tumoral alfa
20.
World J Gastroenterol ; 27(41): 7080-7099, 2021 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-34887629

RESUMEN

The aberrant use of alcohol is a major factor in cancer progression and metastasis. Contributing mechanisms include the systemic effects of alcohol and the exchange of bioactive molecules between cancerous and non-cancerous cells along the brain-gut-liver axis. Such interplay leads to changes in molecular, cellular, and biological functions resulting in cancer progression. Recent investigations have examined the role of extracellular vesicles (EVs) in cancer mechanisms in addition to their contribution as diagnostic biomarkers. Also, EVs are emerging as novel cell-free mediators in pathophysiological scenarios including alcohol-mediated gut microbiome dysbiosis and the release of nanosized EVs into the circulatory system. Interestingly, EVs in cancer patients are enriched with oncogenes, miRNA, lipids, and glycoproteins whose delivery into the hepatic microenvironment may be enhanced by the detrimental effects of alcohol. Proof-of-concept studies indicate that alcohol-associated liver disease is impacted by the effects of exosomes, including altered immune responses, reprogramming of stromal cells, and remodeling of the extracellular matrix. Moreover, the culmination of alcohol-related changes in the liver likely contributes to enhanced hepatic metastases and poor outcomes for cancer patients. This review summarizes the numerous aspects of exosome communications between organs with emphasis on the relationship of EVs in alcohol-associated diseases and cancer metastasis. The potential impact of EV cargo and release along a multi-organ axis is highly relevant to the promotion of tumorigenic mechanisms and metastatic disease. It is hypothesized that EVs target recipient tissues to initiate the formation of prometastatic niches and cancer progression. The study of alcohol-associated mechanisms in metastatic cancers is expected to reveal a better understanding of factors involved in the growth of secondary malignancies as well as novel approaches for therapeutic interventions.


Asunto(s)
Neoplasias Hepáticas , MicroARNs , Comunicación Celular , Comunicación , Humanos , Oncogenes , Microambiente Tumoral
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda