Panx1 knockout promotes preneoplastic aberrant crypt foci development in a chemically induced model of mouse colon carcinogenesis.

Colorectal cancer, which is the third leading cause of cancer-related deaths worldwide, is a multistep disease, featuring preneoplastic aberrant crypt foci (ACF) as the early morphological manifestation. The roles of hemichannel-forming transmembrane Pannexin 1 (Panx1) protein have not been investigated in the context of colon carcinogenesis yet, although it has contrasting roles in other cancer types. Thus, this study was conducted to examine the effects of Panx1 knockout (Panx1-/- ) on the early events of chemically induced colon carcinogenesis in mouse. Wild type (WT) and Panx1-/- female C57BL6J mice were submitted to a chemically induced model of colon carcinogenesis by receiving six intraperitoneal administrations of 1,2-dimethylhydrazine (DMH) carcinogen. Animals were euthanized 8 h (week 7) or 30 weeks (week 37) after the last DMH administration in order to evaluate sub-acute colon toxicity outcomes or the burden of ACF, respectively. At week 7, Panx1 genetic ablation increased DMH-induced genotoxicity in peripheral blood cells, malondialdehyde levels in the colon, and apoptosis (cleaved caspase-3) in colonic crypts. Of note, at week 37, Panx1-/- animals showed an increase in aberrant crypts (AC), ACF mean number, and ACF multiplicity (AC per ACF) by 56%, 57% and 20%, respectively. In essence, our findings indicate that Panx1 genetic ablation promotes preneoplastic ACF development during chemically induced mouse colon carcinogenesis, and a protective role of Panx1 is postulated.

[Spatial-temporal distribution of visceral leishmaniasis in Brazil from 2007 to 2020Distribución espaciotemporal de la leishmaniasis visceral en Brasil en el período 2007-2020]. / Distribuição espaço-temporal da leishmaniose visceral no Brasil no período de 2007 a 2020.

Objective: To analyze the dynamics of the spatial and temporal distribution of visceral leishmaniasis in Brazil from 2007 to 2020. Method: This ecological study focused on the spatial pattern of visceral leishmaniasis cases in Brazil from 2007 to 2020 using data from the Information System for Notifiable Diseases (SINAN). The variables analyzed were the incidence rate of visceral leishmaniasis and the visceral leishmaniasis composite indicator (VLCI), from which triennial thematic maps were constructed. The global Moran index was calculated to assess the existence of spatial autocorrelation, and the local Moran index was used to identify areas with higher and lower risk of visceral leishmaniasis in Brazil. Results: During the study period, there were 48 705 cases of visceral leishmaniasis, with an incidence rate of 25.53 cases per 100 000 population. There was spatial autocorrelation in all triennial blocks, with municipalities in the North and Northeast regions having an incidence equal to or greater than 50 cases per 100 000 population. Regarding the VLCI there was an increase in the number of municipalities classified as low risk for transmission, and a growing presence of state capitals with a classification of very high risk. Conclusion: The incidence of visceral leishmaniasis varied over the trienniums. The border region between the states of Tocantins, Maranhão, and Pará, along with the state of Ceará, stood out in the spatial distribution of the disease incidence and risk stratification by VLCI. These areas should be a priority for surveillance and control efforts for the disease.

Objetivo: Analizar la dinámica de la distribución espaciotemporal de la leishmaniasis visceral en Brasil en el período 2007-2020. Métodos: En este estudio ecológico del patrón de distribución espacial de los casos de leishmaniasis visceral ocurridos en Brasil en el período 2007-2020 se utilizaron datos del sistema de información de enfermedades de declaración obligatoria (SINAN). Las variables analizadas fueron el coeficiente de incidencia de leishmaniasis visceral y el índice compuesto de leishmaniasis visceral, a partir de los cuales se construyeron mapas temáticos trienales. Se calcularon el índice general de Moran para verificar la existencia de autocorrelación espacial, y el índice local de Moran para delimitar las zonas de mayor y menor riesgo de leishmaniasis visceral en Brasil. Resultados: En el período estudiado, hubo 48 705 casos de leishmaniasis visceral, con una incidencia de 25,53 casos por 100 000 habitantes. En todos los bloques trienales hubo una autocorrelación espacial, en la cual varios municipios de las regiones norte y nordeste registraron una incidencia de 50 casos por 100 000 habitantes o una tasa superior. En relación con el índice compuesto de leishmaniasis visceral, se observó un aumento del número de municipios considerados de riesgo bajo de transmisión y una tendencia ascendente del número de ciudades capitales con clasificación de riesgo muy alto. Conclusión: La incidencia de leishmaniasis visceral varió a lo largo de los períodos trienales. La región fronteriza entre Tocantins, Maranhão y Pará, junto con el estado de Ceará, se destacó en términos de la distribución espacial de la incidencia de la enfermedad y la estratificación del riesgo según el índice compuesto de leishmaniasis visceral. Es preciso dar prioridad a estos lugares en lo referente a las medidas y los servicios de vigilancia y control de esta enfermedad.

Sorafenib reduces steatosis-induced fibrogenesis in a human 3D co-culture model of non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) affects around 25% of the worldwide population. Non-alcoholic steatohepatitis (NASH), the more progressive variant of NAFLD, is characterized by steatosis, cellular ballooning, lobular inflammation, and may culminate on hepatic stellate cell (HSC) activation, thus increasing the risk for fibrosis, cirrhosis, and HCC development. Conversely, the antifibrotic effects of sorafenib, an FDA-approved drug for HCC treatment, have been demonstrated in 2D cell cultures and animal models, but its mechanisms in a NAFLD-related microenvironment in vitro requires further investigation. Thus, a human 3D co-culture model of fatty hepatocytes and HSC was established by culturing hepatoma C3A cells, pre-treated with 1.32 mM oleic acid, with HSC LX-2 cells. The fatty C3A/LX-2 spheroids showed morphological and molecular hallmarks of altered lipid metabolism and steatosis-induced fibrogenesis, similarly to the human disease. Sorafenib (15 µM) for 72 hours reduced fatty spheroid viability, and upregulated the expression of lipid oxidation- and hydrolysis-related genes, CPT1 and LIPC, respectively. Sorafenib also inhibited steatosis-induced fibrogenesis by downregulating COL1A1, TGFB1, PDGF, and TIMP1 and by decreasing protein levels of IL-6, TGF-ß1, and TNF-α in fatty spheroids. The demonstration of the antifibrotic properties of sorafenib on steatosis-induced fibrogenesis in a 3D in vitro model of NAFLD supports its clinical use as a therapeutic agent for the treatment of NAFLD/NASH patients.

Identification of genes from the general phenylpropanoid and monolignol-specific metabolism in two sugarcane lignin-contrasting genotypes.

The phenylpropanoid pathway is an important route of secondary metabolism involved in the synthesis of different phenolic compounds such as phenylpropenes, anthocyanins, stilbenoids, flavonoids, and monolignols. The flux toward monolignol biosynthesis through the phenylpropanoid pathway is controlled by specific genes from at least ten families. Lignin polymer is one of the major components of the plant cell wall and is mainly responsible for recalcitrance to saccharification in ethanol production from lignocellulosic biomass. Here, we identified and characterized sugarcane candidate genes from the general phenylpropanoid and monolignol-specific metabolism through a search of the sugarcane EST databases, phylogenetic analysis, a search for conserved amino acid residues important for enzymatic function, and analysis of expression patterns during culm development in two lignin-contrasting genotypes. Of these genes, 15 were cloned and, when available, their loci were identified using the recently released sugarcane genomes from Saccharum hybrid R570 and Saccharum spontaneum cultivars. Our analysis points out that ShPAL1, ShPAL2, ShC4H4, Sh4CL1, ShHCT1, ShC3H1, ShC3H2, ShCCoAOMT1, ShCOMT1, ShF5H1, ShCCR1, ShCAD2, and ShCAD7 are strong candidates to be bona fide lignin biosynthesis genes. Together, the results provide information about the candidate genes involved in monolignol biosynthesis in sugarcane and may provide useful information for further molecular genetic studies in sugarcane.

Protective effect of genetic deletion of pannexin1 in experimental mouse models of acute and chronic liver disease.

Pannexins are transmembrane proteins that form communication channels connecting the cytosol of an individual cell with its extracellular environment. A number of studies have documented the presence of pannexin1 in liver as well as its involvement in inflammatory responses. In this study, it was investigated whether pannexin1 plays a role in acute liver failure and non-alcoholic steatohepatitis, being prototypical acute and chronic liver pathologies, respectively, both featured by liver damage, oxidative stress and inflammation. To this end, wild-type and pannexin1-/- mice were overdosed with acetaminophen for 1, 6, 24 or 48h or were fed a choline-deficient high-fat diet for 8weeks. Evaluation of the effects of genetic pannexin1 deletion was based on a number of clinically relevant read-outs, including markers of liver damage, histopathological analysis, lipid accumulation, protein adduct formation, oxidative stress and inflammation. In parallel, in order to elucidate molecular pathways affected by pannexin1 deletion as well as to mechanistically anchor the clinical observations, whole transcriptome analysis of liver tissue was performed. The results of this study show that pannexin1-/- diseased mice present less liver damage and oxidative stress, while inflammation was only decreased in pannexin1-/- mice in which non-alcoholic steatohepatitis was induced. A multitude of genes related to inflammation, oxidative stress and xenobiotic metabolism were differentially modulated in both liver disease models in wild-type and in pannexin1-/- mice. Overall, the results of this study suggest that pannexin1 may play a role in the pathogenesis of liver disease.

Involvement of connexin43 in acetaminophen-induced liver injury.

BACKGROUND AND AIMS: Being goalkeepers of liver homeostasis, gap junctions are also involved in hepatotoxicity. However, their role in this process is ambiguous, as gap junctions can act as both targets and effectors of liver toxicity. This particularly holds true for drug-induced liver insults. In the present study, the involvement of connexin26, connexin32 and connexin43, the building blocks of liver gap junctions, was investigated in acetaminophen-induced hepatotoxicity. METHODS: C57BL/6 mice were overdosed with 300mg/kg body weight acetaminophen followed by analysis of the expression and localization of connexins as well as monitoring of hepatic gap junction functionality. Furthermore, acetaminophen-induced liver injury was compared between mice genetically deficient in connexin43 and wild type littermates. Evaluation of the toxicological response was based on a set of clinically relevant parameters, including protein adduct formation, measurement of alanine aminotransferase activity, cytokines and glutathione. RESULTS: It was found that gap junction communication deteriorates upon acetaminophen intoxication in wild type mice, which is associated with a switch in mRNA and protein production from connexin32 and connexin26 to connexin43. The upregulation of connexin43 expression is due, at least in part, to de novo production by hepatocytes. Connexin43-deficient animals tended to show increased liver cell death, inflammation and oxidative stress in comparison with wild type counterparts. CONCLUSION: These results suggest that hepatic connexin43-based signaling may protect against acetaminophen-induced liver toxicity.

Connexin32 deficiency is associated with liver injury, inflammation and oxidative stress in experimental non-alcoholic steatohepatitis.

Non-alcoholic steatohepatitis is a highly prevalent liver pathology featured by hepatocellular fat deposition and inflammation. Connexin32, which is the major building block of hepatocellular gap junctions, has a protective role in hepatocarcinogenesis and is downregulated in chronic liver diseases. However, the role of connexin32 in non-alcoholic steatohepatitis remains unclear. Connexin32-/- mice and their wild-type littermates were fed a choline-deficient high-fat diet. The manifestation of non-alcoholic steatohepatitis was evaluated based on a battery of clinically relevant read-outs, including histopathological examination, diverse indicators of inflammation and liver damage, in-depth lipid analysis, assessment of oxidative stress, insulin and glucose tolerance, liver regeneration and lipid-related biomarkers. Overall, more pronounced liver damage, inflammation and oxidative stress were observed in connexin32-/- mice compared to wild-type animals. No differences were found in insulin and glucose tolerance measurements and liver regeneration. However, two lipid-related genes, srebf1 and fabp3, were upregulated in Cx32-/- mice in comparison with wild-type animals. These findings suggest that connexin32-based signalling is not directly involved in steatosis as such, but rather in the sequelae of this process, which underlie progression of non-alcoholic steatohepatitis.

Inhibition of pannexin1 channels alleviates acetaminophen-induced hepatotoxicity.

Pannexins constitute a relatively new family of transmembrane proteins that form channels linking the cytoplasmic compartment with the extracellular environment. The presence of pannexin1 in the liver has been documented previously, where it underlies inflammatory responses, such as those occurring upon ischemia-reperfusion injury. In the present study, we investigated whether pannexin1 plays a role in acute drug-induced liver toxicity. Hepatic expression of pannexin1 was characterized in a mouse model of acetaminophen-induced hepatotoxicity. Subsequently, mice were overdosed with acetaminophen followed by treatment with the pannexin1 channel inhibitor 10Panx1. Sampling was performed 1, 3, 6, 24 and 48 h after acetaminophen administration. Evaluation of the effects of pannexin1 channel inhibition was based on a number of clinically relevant readouts, including protein adduct formation, measurement of aminotransferase activity and histopathological examination of liver tissue as well as on a series of markers of inflammation, oxidative stress and regeneration. Although no significant differences were found in histopathological analysis, pannexin1 channel inhibition reduced serum levels of alanine and aspartate aminotransferase. This was paralleled by a reduced amount of neutrophils recruited to the liver. Furthermore, alterations in the oxidized status were noticed with upregulation of glutathione levels upon suppression of pannexin1 channel opening. Concomitant promotion of regenerative activity was detected as judged on increased proliferating cell nuclear antigen protein quantities in 10Panx1-treated mice. Pannexin1 channels are important actors in liver injury triggered by acetaminophen. Inhibition of pannexin1 channel opening could represent a novel approach for the treatment of drug-induced hepatotoxicity.

Connexins, Pannexins, and Their Channels in Fibroproliferative Diseases.

Cellular and molecular mechanisms of wound healing, tissue repair, and fibrogenesis are established in different organs and are essential for the maintenance of function and tissue integrity after cell injury. These mechanisms are also involved in a plethora of fibroproliferative diseases or organ-specific fibrotic disorders, all of which are associated with the excessive deposition of extracellular matrix components. Fibroblasts, which are key cells in tissue repair and fibrogenesis, rely on communicative cellular networks to ensure efficient control of these processes and to prevent abnormal accumulation of extracellular matrix into the tissue. Despite the significant impact on human health, and thus the epidemiologic relevance, there is still no effective treatment for most fibrosis-related diseases. This paper provides an overview of current concepts and mechanisms involved in the participation of cellular communication via connexin-based pores as well as pannexin-based channels in the processes of tissue repair and fibrogenesis in chronic diseases. Understanding these mechanisms may contribute to the development of new therapeutic strategies to clinically manage fibroproliferative diseases and organ-specific fibrotic disorders.

Connexin32: a mediator of acetaminophen-induced liver injury?

Connexin32 is the building block of hepatocellular gap junctions, which control direct intercellular communication and thereby act as goalkeepers of liver homeostasis. This study was set up to investigate whether connexin32 is involved in hepatotoxicity induced by the analgesic and antipyretic drug acetaminophen. To this end, whole body connexin32 knock-out mice were overdosed with acetaminophen followed by sampling at different time points within a 24-h time frame. Evaluation was done based upon a series of clinically and mechanistically relevant read-outs, including protein adduct formation, histopathological examination, measurement of alanine aminotransferase activity, cytokine production, levels of reduced and oxidized glutathione and hepatic protein amounts of proliferating cell nuclear antigen. In essence, it was found that genetic ablation of connexin32 has no influence on several key events in acetaminophen-induced hepatotoxicity, including cell death, inflammation or oxidative stress, yet it does affect production of protein adducts as well as proliferating cell nuclear antigen steady-state protein levels. This outcome is not in line with previous studies, which are contradicting on their own, as both amplification and alleviation of this toxicological process by connexin32 have been described. This could question the suitability of the currently available models and tools to investigate the role of connexin32 in acetaminophen-triggered hepatotoxicity.

Long-term prospective study of the influence of estrone levels on events in postmenopausal women with or at high risk for coronary artery disease.

BACKGROUND: The link between endogenous estrogen, coronary artery disease (CAD), and death in postmenopausal women is uncertain. We analyzed the association between death and blood levels of estrone in postmenopausal women with known coronary artery disease (CAD) or with a high-risk factor score for CAD. METHODS: 251 postmenopausal women age 50-90 years not on estrogen therapy. Fasting blood for estrone and heart disease risk factors were collected at baseline. Women were grouped according to their estrone levels (<15 and ≥15 pg/mL). Fatal events were recorded after 5.8 ± 1.4 years of followup. RESULTS: The Kaplan-Meier survival curve showed a significant trend (P = 0.039) of greater all-cause mortality in women with low estrone levels (<15 pg/mL). Cox multivariate regression analysis model adjusted for body mass index, diabetes, dyslipidemia, family history, and estrone showed estrone (OR = 0.45; P = 0.038) as the only independent variable for all-cause mortality. Multivariate regression model adjusted for age, body mass index, hypertension, diabetes, dyslipidemia, family history, and estrone showed that only age (OR = 1.06; P = 0.017) was an independent predictor of all-cause mortality. CONCLUSIONS: Postmenopausal women with known CAD or with a high-risk factor score for CAD and low estrone levels (<15 pg/mL) had increased all-cause mortality.

The Implications of Connexin 43 Deficiency during the Early Stages of Chemically Induced Mouse Colon Carcinogenesis.

Colorectal cancer (CRC), associated with an increased intake of processed red meats, saturated fats, and simple carbohydrates accompanied by low dietary fiber, fruits, and vegetables consumption, presents a high epidemiological burden. Connexin43 (Cx43) protein, which forms gap junctions or hemichannels, has tumor suppressor or oncogenic activities in a cancer type- and stage-dependent manner. Cx43 expression varies during colon carcinogenesis, and its functional role is not fully understood. Thus, we evaluated the implications of Cx43 heterologous deletion (Cx43+/-) during the early stages of a chemically induced model of colon carcinogenesis. Female C57BL/6J mice (wild-type or Cx43+/-) were submitted to a colon carcinogenesis model induced by 1,2 dimethylhydrazine (DMH). Mice were euthanized eight hours (week 7) or 30 weeks (week 37) after the last DMH administration to evaluate subacute colon toxicity outcomes or the burden of (pre)neoplastic lesions, respectively. At week 7, Cx43 deficiency inferred no alterations in the DMH-induced increase in systemic (peripheral blood), in situ (colonocytes) DNA damage, and apoptosis in the colonocytes. At week 30, Cx43+/- mice presented an increase in preneoplastic aberrant crypt foci (ACF) multiplicity, while no alterations were observed in colorectal adenoma (CRA) occurrence, multiplicity, volume, proliferation, growth, and ß-catenin immunoexpression. Similarly, an in silico analysis of human CRA showed decreased mRNA expression of Cx43 with no correlation with proliferation, apoptosis, and ß-catenin markers. These findings indicate the discrete role of Cx43 in the early stages of chemically induced mouse colon carcinogenesis.

Hepatocellular Carcinoma in a Free-Ranging Three-Toed Sloth (Bradypus variegatus).

The increasing interest of tumors in wildlife is important for biodiversity conservation and for monitoring environmental agents and/or contaminants with potential impact on human health. Here we described the occurrence of hepatocellular carcinoma (HCC) in noncirrhotic liver of a free-ranging three-toed sloth (Bradypus variegatus) from the Atlantic Forest biome in Brazil. The HCC showed a moderate mononuclear inflammatory infiltrate within the tumor tissue but with no inflammation and fibrosis in the adjacent liver tissue. Upon immunohistochemistry, neoplastic cells were diffusely positive for HepPar-1 and glutamine-synthetase presenting an irregular and random immunostaining pattern; ß-catenin was positive in the cytoplasmic membrane of malignant hepatocytes; and cytokeratin 19 immunostaining was restricted to bile duct epithelial cells. The liver tissue was negative for HBV-like and HCV-like viruses assessed by molecular tests. The potential similarity of pathogenesis may reinforce the need for research on environmental and/or infectious agents associated with HCC that may contribute to the understanding of cancer in wildlife.

Novel gammaherpesvirus associated with primary gastric T-cell lymphoma in a free-ranging giant armadillo in Brazil.

The number of viral-associated neoplasms reported in wildlife has increased over the last decades, likely because of growing research efforts and a potentially greater burden of carcinogenic pathogens. Herein, we describe a primary gastric T-cell lymphoma in one free-ranging giant armadillo (Priodontes maximus) from Brazilian Pantanal infected by a novel gammaherpesvirus, proposed as Cingulatid gammaherpesvirus 1 (CiHV-1). By chromogenic in situ hybridisation against Epstein-Barr virus some neoplastic cells were labeled. Subsequently, a molecular screening was carried out to detect the occurrence of this pathogen in other giant armadillos in the same region. Overall, this novel virus was detected in 14.3% (3/21) of the tested giant armadillos. We suggest this herpesvirus, the first in Xenarthra, as a plausible aetiology of the neoplasm. The implications of CiHV-1 for this species are uncertain; while no outbreaks of disease have been recorded, the present study raises concerns. Further research is warranted to assess the real significance of CiHV-1 and its potential oncogenic role in this species.

Spatial analysis of AIDS in the state of Maranhão: an ecological study 2011-2018.

OBJECTIVE: Analyze the spatio-temporal distribution of AIDS cases in Maranhão. METHODS: Ecological study of AIDS cases in the Notifiable Diseases Information System, 2011-2018. Gross and adjusted incidences were calculated using the Baysean method; then, the Moran Global and Local Indices to observe the existence of spatial autocorrelation of the cases and for the delimitation of high and low risk clusters. RESULTS: 6,349 cases were reported, which were distributed heterogeneously. There was an advance of cases to new areas and persistence in old areas, such as in the capital São Luís and its surroundings. The dissemination did not occur at random, with positive spatial autocorrelation, with evidence of the formation of clusters in the municipalities of São Luís, São José de Ribamar and Paço do Lumiar. CONCLUSION: High-risk areas have been identified and should be considered a priority for investment in health, management, and organization of health services.

Genetic variants of BRCA1 and BRCA2 genes in cats with mammary gland carcinoma.

Mammary tumours are the first and third most incident neoplasm in women and cats, respectively. Approximately 85% of feline mammary gland tumours are malignant and aggressive, especially the triple-negative and HER-2+ molecular subtypes. Triple-negative basal-like feline mammary carcinomas (FMCs) are considered suitable models due to the clinical and morphological similarities with human basal-like triple-negative breast cancer (TNBC). In women, TNBC has a poor prognosis and is often associated with mutations in the tumour suppressor genes BRCA1 and BRCA2. In light of this, the aim of the present investigation was to screen somatic and germline variants of BRCA1 and BRCA2 in nine female cats bearing FMCs. Matched whole blood and FMC samples were obtained for genetic analysis. Additional tumour samples were obtained for histopathological and immunohistochemical evaluation. Genomic DNA was isolated and 27 exonic regions of BRCA1 and BRCA2 genes were amplified and screened by next-generation sequencing. A somatic variant with high functional impact was found in exon 11 of BRCA2 at a frequency of 4.34% in one FMC-bearing cat. Four germline variants with moderate impact were detected in three of the nine FMC-bearing cats and were restricted to exon 9 of BRCA1. It is concluded that the germline genetic variants found in one-third of FMC-bearing animals might be associated with a higher risk of hereditary mammary carcinogenesis.

Immunoexpression and Prognostic Significance of Multidrug Resistance Markers in Feline Mammary Carcinomas.

Feline mammary carcinomas (FMCs) are commonly characterized by high clinical aggressiveness and poor prognosis. FMCs share many features with the corresponding human disease, allowing the comparative investigation of tumour biology and therapeutic strategies, including multidrug resistance (MDR) mechanisms. Although transporting/binding proteins, including permeability glycoprotein (P-gp), lung resistance protein (LRP) and metallothionein (MT), are frequently associated with tumour aggressiveness and unresponsiveness to chemotherapy in human breast cancer, they have not been analysed in FMCs. We investigated the immunoexpression of P-gp, LRP and MT in FMCs and their correlation with clinicopathological parameters and overall survival (OS) time in 46 FMCs, with a median follow-up period of 289 days. These markers were co-expressed in 85% of tumours. P-gp was expressed in 93.4% of FMCs and was positively associated with tumour grade (P = 0.049). While unequivocally observed in all FMCs, LRP immunoexpression did not correlate with any clinicopathological parameters or OS. Expression of MT was significant in triple-negative basal- and normal-like molecular subtypes of FMCs (P = 0.023). The concurrent expression of MDR proteins indicates the potential existence of chemotherapy resistance-related mechanisms in FMCs. The positive association between P-gp and MT immunoexpression and aggressive phenotypes could open new therapeutic and translational strategies for FMCs.

In Vivo and In Vitro Models of Hepatocellular Carcinoma: Current Strategies for Translational Modeling.

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the third leading cause of cancer-related death globally. HCC is a complex multistep disease and usually emerges in the setting of chronic liver diseases. The molecular pathogenesis of HCC varies according to the etiology, mainly caused by chronic hepatitis B and C virus infections, chronic alcohol consumption, aflatoxin-contaminated food, and non-alcoholic fatty liver disease associated with metabolic syndrome or diabetes mellitus. The establishment of HCC models has become essential for both basic and translational research to improve our understanding of the pathophysiology and unravel new molecular drivers of this disease. The ideal model should recapitulate key events observed during hepatocarcinogenesis and HCC progression in view of establishing effective diagnostic and therapeutic strategies to be translated into clinical practice. Despite considerable efforts currently devoted to liver cancer research, only a few anti-HCC drugs are available, and patient prognosis and survival are still poor. The present paper provides a state-of-the-art overview of in vivo and in vitro models used for translational modeling of HCC with a specific focus on their key molecular hallmarks.

The combination of coffee compounds attenuates early fibrosis-associated hepatocarcinogenesis in mice: involvement of miRNA profile modulation.

Aberrant microRNA expression implicates on hepatocellular carcinoma (HCC) development. Conversely, coffee consumption reduces by ~40% the risk for fibrosis/cirrhosis and HCC, while decaffeinated coffee does not. It is currently unknown whether these protective effects are related to caffeine (CAF), or to its combination with other common and/or highly bioavailable coffee compounds, such as trigonelline (TRI) and chlorogenic acid (CGA). We evaluated whether CAF individually or combined with TRI and/or CGA alleviates fibrosis-associated hepatocarcinogenesis, examining the involvement of miRNA profile modulation. Then, male C3H/HeJ mice were submitted to a diethylnitrosamine/carbon tetrachloride-induced model. Animals received CAF (50 mg/kg), CAF+TRI (50 and 25 mg/kg), CAF+CGA (50 and 25 mg/kg) or CAF+TRI+CGA (50, 25 and 25 mg/kg), intragastrically, 5×/week, for 10 weeks. Only CAF+TRI+CGA combination reduced the incidence, number and proliferation (Ki-67) of hepatocellular preneoplastic foci while enhanced apoptosis (cleaved caspase-3) in adjacent parenchyma. CAF+TRI+CGA treatment also decreased hepatic oxidative stress and enhanced the antioxidant Nrf2 axis. CAF+TRI+CGA had the most pronounced effects on decreasing hepatic pro-inflammatory IL-17 and NFκB, contributing to reduce CD68-positive macrophage number, stellate cell activation, and collagen deposition. In agreement, CAF+TRI+CGA upregulated tumor suppressors miR-144-3p, miR-376a-3p and antifibrotic miR-15b-5p, frequently deregulated in human HCC. CAF+TRI+CGA reduced the hepatic protein levels of pro-proliferative EGFR (miR-144-3p target), antiapoptotic Bcl-2 family members (miR-15b-5p targets), and the number of PCNA (miR-376a-3p target) positive hepatocytes in preneoplastic foci. Our results suggest that the combination of most common and highly bioavailable coffee compounds, rather than CAF individually, attenuates fibrosis-associated hepatocarcinogenesis by modulating miRNA expression profile.