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1.
Mol Cell ; 77(4): 748-760.e9, 2020 02 20.
Article in English | MEDLINE | ID: mdl-31785928

ABSTRACT

Mutations affecting exon 9 of the CALR gene lead to the generation of a C-terminally modified calreticulin (CALR) protein that lacks the KDEL endoplasmic reticulum (ER) retention signal and consequently mislocalizes outside of the ER where it activates the thrombopoietin receptor in a cell-autonomous fashion, thus driving myeloproliferative diseases. Here, we used the retention using selective hooks (RUSH) assay to monitor the trafficking of CALR. We found that exon-9-mutated CALR was released from cells in response to the biotin-mediated detachment from its ER-localized hook, in vitro and in vivo. Cellular CALR release was confirmed in suitable mouse models bearing exon-9-mutated hematopoietic systems or tumors. Extracellular CALR mediated immunomodulatory effects and inhibited the phagocytosis of dying cancer cells by dendritic cells (DC), thereby suppressing antineoplastic immune responses elicited by chemotherapeutic agents or by PD-1 blockade. Altogether, our results demonstrate paracrine immunosuppressive effects for exon-9-mutated CALR.


Subject(s)
Calreticulin/genetics , Immune Tolerance/genetics , Mutation , Neoplasms/genetics , Neoplasms/immunology , Animals , Calreticulin/metabolism , Cell Line, Tumor , Humans , Mice , Mice, Inbred C57BL , Phagocytosis
2.
Proc Natl Acad Sci U S A ; 119(41): e2207344119, 2022 10 11.
Article in English | MEDLINE | ID: mdl-36191214

ABSTRACT

Acyl-coenzyme A (CoA)-binding protein (ACBP), also known as diazepam-binding inhibitor (DBI), is an extracellular feedback regulator of autophagy. Here, we report that injection of a monoclonal antibody neutralizing ACBP/DBI (α-DBI) protects the murine liver against ischemia/reperfusion damage, intoxication by acetaminophen and concanavalin A, and nonalcoholic steatohepatitis caused by methionine/choline-deficient diet as well as against liver fibrosis induced by bile duct ligation or carbon tetrachloride. α-DBI downregulated proinflammatory and profibrotic genes and upregulated antioxidant defenses and fatty acid oxidation in the liver. The hepatoprotective effects of α-DBI were mimicked by the induction of ACBP/DBI-specific autoantibodies, an inducible Acbp/Dbi knockout or a constitutive Gabrg2F77I mutation that abolishes ACBP/DBI binding to the GABAA receptor. Liver-protective α-DBI effects were lost when autophagy was pharmacologically blocked or genetically inhibited by knockout of Atg4b. Of note, α-DBI also reduced myocardium infarction and lung fibrosis, supporting the contention that it mediates broad organ-protective effects against multiple insults.


Subject(s)
Diazepam Binding Inhibitor , Receptors, GABA-A , Animals , Mice , Acetaminophen , Antibodies, Monoclonal/metabolism , Antioxidants , Autoantibodies/metabolism , Autophagy , Carbon Tetrachloride , Carrier Proteins/genetics , Choline , Coenzyme A/metabolism , Concanavalin A/metabolism , Diazepam , Diazepam Binding Inhibitor/metabolism , Fatty Acids/metabolism , Fibrosis , Inflammation , Methionine
3.
Blood ; 139(3): 384-398, 2022 01 20.
Article in English | MEDLINE | ID: mdl-34232979

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoid malignancy affecting adults. The NF-κB transcription factor family is activated by 2 main pathways, the canonical and the alternative NF-κB activation pathway, with different functions. The alternative NF-κB pathway leads to activation of the transcriptionally active RelB NF-κB subunit. Alternative NF-κB activation status and its role in DLBCL pathogenesis remain undefined. Here, we reveal a frequent activation of RelB in a large cohort of DLBCL patients and cell lines, independently of their activated B-cell-like or germinal center B-cell-like subtype. RelB activity defines a new subset of patients with DLBCL and a peculiar gene expression profile and mutational pattern. Importantly, RelB activation does not correlate with the MCD genetic subtype, enriched for activated B-cell-like tumors carrying MYD88L265P and CD79B mutations that cooperatively activate canonical NF-κB, thus indicating that current genetic tools to evaluate NF-κB activity in DLBCL do not provide information on the alternative NF-κB activation. Furthermore, the newly defined RelB-positive subgroup of patients with DLBCL exhibits a dismal outcome after immunochemotherapy. Functional studies revealed that RelB confers DLBCL cell resistance to DNA damage-induced apoptosis in response to doxorubicin, a genotoxic agent used in the front-line treatment of DLBCL. We also show that RelB positivity is associated with high expression of cellular inhibitor of apoptosis protein 2 (cIAP2). Altogether, RelB activation can be used to refine the prognostic stratification of DLBCL and may contribute to subvert the therapeutic DNA damage response in a segment of patients with DLBCL.


Subject(s)
Lymphoma, Large B-Cell, Diffuse/metabolism , NF-kappa B/metabolism , Transcription Factor RelB/metabolism , Apoptosis , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Humans , Lymphoma, Large B-Cell, Diffuse/genetics , NF-kappa B/genetics , Transcription Factor RelB/genetics , Transcriptional Activation
4.
Mol Cancer ; 22(1): 128, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37563591

ABSTRACT

Protein regulator of cytokinesis 1 (PRC1) is involved in cytokinesis. Growing evidence suggests the association of PRC1 with multiple cancers. Here, we unveil that, in 28 cancer types, PRC1 is higher expressed in tumor tissues than in non-malignant tissues. Overexpression of PRC1 indicates unfavorable prognostic value, especially in ACC, LGG, KIRP, LICH, LUAD, MESO, PAAD, SARC and UCEC, while methylation of the PRC1 gene at sites associated with its inactivation has a favorable prognostic value in ACC, KIRP, LUAD, MESO, KIRP and LGG. Differentially expressed genes (DEGs) associated with high (> median) PRC1 expression contribute to key signaling pathways related with cell cycle, DNA damage and repair, EMT, cell migration, invasion and cell proliferation in most cancer types. More specifically, the DEGs involved in RAS/RAF/MAPK, PI3K/AKT, WNT, NOTCH, TGF-ß, integrin, EMT process, focal adhesion, RHO GTPase-related pathway or microtubule cytoskeleton regulation are upregulated when PRC1 expression is above median, as confirmed for most cancers. Most importantly, high expression of PRC1 appears to be associated with an overabundance of poor-prognosis TH2 cells. Furthermore, positive correlations of PRC1 and some immune checkpoint genes (CD274, CTLA4, HAVCR2, LAG3, PDCD1, PDCD1LG2, TIGIT, and CD86) were observed in several cancers, especially BLCA, BRCA, KIRC, LUAD, LIHC, PRAD and THCA. These findings plead in favor of further studies validating the diagnostic and prognostic impact of PRC1 as well as the elaboration of pharmacological strategies for targeting PRC1.


Subject(s)
Cytokinesis , Neoplasms , Humans , Phosphatidylinositol 3-Kinases , Neoplasms/genetics , Cell Proliferation , Signal Transduction
5.
Immunity ; 38(4): 729-41, 2013 Apr 18.
Article in English | MEDLINE | ID: mdl-23562161

ABSTRACT

The therapeutic efficacy of anthracyclines relies on antitumor immune responses elicited by dying cancer cells. How chemotherapy-induced cell death leads to efficient antigen presentation to T cells, however, remains a conundrum. We found that intratumoral CD11c(+)CD11b(+)Ly6C(hi) cells, which displayed some characteristics of inflammatory dendritic cells and included granulomonocytic precursors, were crucial for anthracycline-induced anticancer immune responses. ATP released by dying cancer cells recruited myeloid cells into tumors and stimulated the local differentiation of CD11c(+)CD11b(+)Ly6C(hi) cells. Such cells efficiently engulfed tumor antigens in situ and presented them to T lymphocytes, thus vaccinating mice, upon adoptive transfer, against a challenge with cancer cells. Manipulations preventing tumor infiltration by CD11c(+)CD11b(+)Ly6C(hi) cells, such as the local overexpression of ectonucleotidases, the blockade of purinergic receptors, or the neutralization of CD11b, abolished the immune system-dependent antitumor activity of anthracyclines. Our results identify a subset of tumor-infiltrating leukocytes as therapy-relevant antigen-presenting cells.


Subject(s)
Anthracyclines/administration & dosage , Antigen-Presenting Cells/immunology , Antineoplastic Agents/administration & dosage , Dendritic Cells/immunology , Neoplasms, Experimental/immunology , Adoptive Transfer , Animals , Anthracyclines/adverse effects , Antigens, Ly/metabolism , Antigens, Neoplasm/immunology , Antineoplastic Agents/adverse effects , Apoptosis , CD11b Antigen/metabolism , CD11c Antigen/metabolism , Cell Differentiation/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Granulocyte Precursor Cells/immunology , Immunity, Cellular , Mice , Mice, Inbred C57BL , Monocyte-Macrophage Precursor Cells/immunology , Neoplasms, Experimental/drug therapy , Nucleotidases/metabolism , Receptors, Purinergic/metabolism
6.
Mol Cell ; 53(5): 710-25, 2014 Mar 06.
Article in English | MEDLINE | ID: mdl-24560926

ABSTRACT

Acetyl-coenzyme A (AcCoA) is a major integrator of the nutritional status at the crossroads of fat, sugar, and protein catabolism. Here we show that nutrient starvation causes rapid depletion of AcCoA. AcCoA depletion entailed the commensurate reduction in the overall acetylation of cytoplasmic proteins, as well as the induction of autophagy, a homeostatic process of self-digestion. Multiple distinct manipulations designed to increase or reduce cytosolic AcCoA led to the suppression or induction of autophagy, respectively, both in cultured human cells and in mice. Moreover, maintenance of high AcCoA levels inhibited maladaptive autophagy in a model of cardiac pressure overload. Depletion of AcCoA reduced the activity of the acetyltransferase EP300, and EP300 was required for the suppression of autophagy by high AcCoA levels. Altogether, our results indicate that cytosolic AcCoA functions as a central metabolic regulator of autophagy, thus delineating AcCoA-centered pharmacological strategies that allow for the therapeutic manipulation of autophagy.


Subject(s)
Acetyl Coenzyme A/chemistry , Autophagy , Cytosol/enzymology , Gene Expression Regulation, Enzymologic , Adenosine Triphosphate/chemistry , Animals , Cell Line, Tumor , Cell Nucleus/metabolism , Cytoplasm/metabolism , Cytosol/metabolism , E1A-Associated p300 Protein/chemistry , Green Fluorescent Proteins/metabolism , HCT116 Cells , HeLa Cells , Humans , Ketoglutaric Acids/chemistry , Mice , Mice, Inbred C57BL , Microscopy, Fluorescence , Mitochondria/metabolism , RNA, Small Interfering/metabolism
7.
Int J Mol Sci ; 23(7)2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35408859

ABSTRACT

Amyloidoses are characterized by the accumulation and aggregation of misfolded proteins into fibrils in different organs, leading to cell death and consequent organ dysfunction. The specific substitution of Leu 75 for Pro in Apolipoprotein A-I protein sequence (ApoA-I; L75P-ApoA-I) results in late onset amyloidosis, where deposition of extracellular protein aggregates damages the normal functions of the liver. In this work, we describe that the autophagic process is inhibited in the presence of the L75P-ApoA-I amyloidogenic variant in stably transfected human hepatocyte carcinoma cells. The L75P-ApoA-I amyloidogenic variant alters the redox status of the cells, resulting into excessive mitochondrial stress and consequent cell death. Moreover, L75P-ApoA-I induces an impairment of the autophagic flux. Pharmacological induction of autophagy or transfection-enforced overexpression of the pro-autophagic transcription factor EB (TFEB) restores proficient proteostasis and reduces oxidative stress in these experimental settings, suggesting that pharmacological stimulation of autophagy could be a promising target to alleviate ApoA-I amyloidosis.


Subject(s)
Amyloidosis , Immunoglobulin Light-chain Amyloidosis , Amyloidosis/genetics , Apolipoprotein A-I/genetics , Apolipoprotein A-I/metabolism , Autophagy/genetics , Humans , Protein Aggregates
8.
Public Health Nurs ; 39(2): 423-430, 2022 03.
Article in English | MEDLINE | ID: mdl-34529864

ABSTRACT

OBJECTIVE: To compare the effect of using an educational booklet and a video alone or together in promoting maternal self-efficacy to prevent childhood diarrhea. DESIGN AND SAMPLE: Randomized multicenter clinical trial with 522 mothers of children under 5 years of age from northeastern Brazil. They were allocated into eight groups, according to the city: metropolis - video alone (N = 61), booklet alone (N = 60), booklet and video along (N = 60), without intervention (N = 60); countryside - booklet alone (N = 70), video alone (N = 70), booklet and video along (N = 71), without intervention (N = 70). MEASUREMENTS: A sociodemographic form and the Maternal Self-Efficacy Scale for preventing early childhood diarrhea. RESULTS: Increases in self-efficacy scores were observed in all experimental groups after the educational intervention. Urban mothers living had greater self-efficacy than rural mothers. This result was verified in the video alone group (p = .036) and without intervention group (p = .003). Mothers in all intervention groups, regardless of the educational intervention used, had higher self-efficacy scores than the comparison group mothers (p < .05). CONCLUSION: The tested educational technologies promoted maternal self-efficacy to prevent childhood diarrhea, regardless of whether they are applied alone or in combination.


Subject(s)
Mothers , Self Efficacy , Brazil , Child , Child, Preschool , Diarrhea/prevention & control , Female , Humans , Technology
9.
Doc Ophthalmol ; 138(1): 43-54, 2019 02.
Article in English | MEDLINE | ID: mdl-30617670

ABSTRACT

PURPOSE: Visual evoked cortical potentials (VECPs) are useful for investigating the mechanisms and dysfunctions of color vision. Chromatic sinusoidal gratings are generally used to elicit VECPs, but they require long psychophysical measurements to match the perceptual luminance between their stripes. An alternative method is to use pseudoisochromatic stimuli, which makes use of luminance noise to mask luminance clues and force the target perception to be dependent on chromatic contrast. In this study, we compared VECPs generated by sinusoidal gratings and pseudoisochromatic gratings. Contrary to chromatic sinusoidal gratings, pseudoisochromatic stimuli do not require the use of previous methods to find the equiluminance of the stimulus. METHODS: Normal trichromats were recruited to be tested with red-green chromatic sinusoidal gratings and pseudoisochromatic gratings presented by pattern onset-offset and pattern reversal modes in five spatial frequencies. In addition, we also tested four different chromatic contrast pairs in pattern onset-offset mode presentation in five trichromats and one colorblind subject (deuteranope). RESULTS: Pattern onset-offset VECPs elicited by sinusoidal gratings had a larger amplitude than those obtained with pseudoisochromatic stimuli, whereas pattern reversal VECPs elicited by pseudoisochromatic gratings had similar amplitudes compared to those elicited by sinusoidal gratings. We found no difference between the VECP amplitudes elicited by sinusoidal and pseudoisochromatic gratings containing different chromatic contrast. Color-blind subjects displayed absent or small responses to the stimuli. CONCLUSION: Pseudoisochromatic stimulus can be an alternative stimulus to generate VECPs dominated by the chromatic mechanism.


Subject(s)
Color Perception/physiology , Color Vision Defects/physiopathology , Evoked Potentials, Visual/physiology , Photic Stimulation , Visual Cortex/physiology , Adult , Color Vision Defects/diagnosis , Contrast Sensitivity/physiology , Electroretinography , Female , Humans , Male , Pattern Recognition, Visual , Psychophysics , Young Adult
10.
Mol Cell ; 42(1): 1-3, 2011 Apr 08.
Article in English | MEDLINE | ID: mdl-21474062

ABSTRACT

In this issue of Molecular Cell, Elgendy et al. suggest that Ras-induced autophagy may kill tumor cells on the verge of oncogenic transformation, providing a contrast to recent reports indicating that autophagy is required for optimal growth of Ras-driven cancers.

11.
Semin Immunol ; 22(3): 113-24, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20403709

ABSTRACT

An attractive, yet hitherto unproven concept predicts that the promotion of tumor regression should elicit the host's immune response against residual tumor cells to achieve an optimal therapeutic effect. In a way, chemo- or radiotherapy must trigger "danger signals" emitted from immunogenic cell death and hence elicit "danger associated molecular patterns" to stimulate powerful anticancer immune responses. Here, based on the recent experimental and clinical evidence, we will discuss the molecular identity of the multiple checkpoints that dictate the success of "immunogenic chemotherapy" at the levels of the drug, of the tumor cell and of the host immune system.


Subject(s)
Drug Therapy , Immunotherapy/methods , Neoplasms , Radiotherapy , Cancer Vaccines/immunology , Humans , Immune System , Interferon-gamma/metabolism , Interleukin-1beta/metabolism , Neoplasms/immunology , Neoplasms/therapy
12.
Drug Resist Updat ; 16(1-2): 10-21, 2013.
Article in English | MEDLINE | ID: mdl-23434004

ABSTRACT

Maintenance of both normal epithelial tissues and their malignant counterparts is supported by the host tissue stroma. The tumor stroma mainly consists of the basement membrane, fibroblasts, extracellular matrix, immune cells, and vasculature. Although most host cells in the stroma possess certain tumor-suppressing abilities, the stroma will change during malignancy and eventually promote growth, invasion, and metastasis. There is growing evidence that the stroma influences importantly the response to radiation therapy (RT). On the one hand, irradiation releases numerous inflammatory cytokines within the extracellular matrix and activates tumor specific antigens presentation, triggering an immune reaction that contributes to the antitumor effect seen after RT. On the other hand, the stroma significantly contributes to radioresistance but also increases the metastatic risk. Indeed, fibroblasts, which are major actors of the impact of stroma on tumor response, are involved in activation of autocrine and paracrine molecular signaling pathways regulating tumor cell proliferation, cell death, response to hypoxia, DNA repair systems and mesenchymal-epithelial transition. They are also actors of the peritumoral desmoplastic reaction, which decreases tumor radiosensitivity. The irradiated stroma can also contribute to tumor relapse after RT through recruitment of bone marrow-derived progenitors that contribute to local tumor relapse through neovascularization. It is therefore time to question preclinical models that would not take into account this impact of stroma. The increasing knowledge of the relationship between stroma and response to IR could help developing innovative strategies for potentially improve antitumor effect of RT.


Subject(s)
Neoplasm Proteins/genetics , Neoplasms/blood supply , Neoplasms/radiotherapy , Radiation Tolerance , Basement Membrane/pathology , Basement Membrane/radiation effects , Cytokines/genetics , Cytokines/immunology , Dendritic Cells/pathology , Dendritic Cells/radiation effects , Extracellular Matrix/pathology , Extracellular Matrix/radiation effects , Fibroblasts/pathology , Fibroblasts/radiation effects , Gene Expression Regulation, Neoplastic/radiation effects , Humans , Lymphocytes/pathology , Lymphocytes/radiation effects , Neoplasm Proteins/immunology , Neoplasms/immunology , Neoplasms/physiopathology , Neovascularization, Pathologic , Radiation, Ionizing , Signal Transduction/radiation effects , Tumor Microenvironment/radiation effects
13.
Methods Mol Biol ; 2769: 1-13, 2024.
Article in English | MEDLINE | ID: mdl-38315385

ABSTRACT

Orthotopic models of hepatocellular carcinoma (HCC) consist in the implantation of tumor cells into the liver by direct intrahepatic injection. In this model, tumorigenesis is triggered within the hepatic microenvironment, thus mimicking the metastatic behavior of HCC. Herein, we detail a surgically mediated methodology that allows the reproducible and effective induction of liver-sessile tumors in mice. We enumerate the steps to be followed before and after the surgical procedure, including HCC cell preparation, the quantity of cancer cells to be injected, presurgical preparation of the mice, and finally, postoperative care. The surgical procedure involves laparotomy to expose the liver, injection of cells into the left-lateral hepatic lobe, and closure of the incision with sutures followed by wound clips. We also provide information concerning the subsequent tumor growth follow-up, as well as the application of bioluminescence imaging to monitor tumor development.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mice , Animals , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Cell Line , Diagnostic Imaging , Cell Line, Tumor , Disease Models, Animal , Tumor Microenvironment
14.
Methods Mol Biol ; 2769: 57-65, 2024.
Article in English | MEDLINE | ID: mdl-38315388

ABSTRACT

Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD). Obesity is a known risk factor of NASH, which, in turn, increases the risk of developing cirrhosis (liver scarring) and hepatocellular carcinoma (HCC). In addition to being a potentially life-threatening condition, public health concerns surrounding NASH are amplified by the lack of FDA-approved treatments. Although various preclinical models reflecting both the histopathology and the pathophysiological progression of human NASH exist, most of these models are diet-based and require 6-13 months for NASH symptom manifestation. Here, we describe a simple and rapid-progression model of NASH and NASH-driven HCC in mice. Mice received a western diet equivalent (WD; i.e., a high-fat, high-fructose, and high-cholesterol diet), high-sugar water (23.1 g/L fructose and 18.9 g/L glucose), and weekly intraperitoneal injections of carbon tetrachloride (CCl4) at a dose of 0.2 µL/g of body weight. The resulting phenotype, consisting in liver fibrosis and HCC, appeared within 24 weeks of diet/treatment initiation and presented similar histological and transcriptomic features as human NASH and NASH-driven HCC, thereby supporting the adequacy of this preclinical model for the development and evaluation of drugs that can prevent or reverse these diseases.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Humans , Mice , Animals , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/pathology , Carcinoma, Hepatocellular/genetics , Carbon Tetrachloride/toxicity , Liver Neoplasms/pathology , Diet, Western/adverse effects , Disease Models, Animal , Liver Cirrhosis/pathology , Fructose , Diet, High-Fat/adverse effects , Liver/pathology , Mice, Inbred C57BL
15.
Methods Mol Biol ; 2769: 67-75, 2024.
Article in English | MEDLINE | ID: mdl-38315389

ABSTRACT

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and the second most common cause of cancer-related death. HCC is associated to chronic diseases such as viral hepatitis, alcoholic, and non-alcoholic fatty liver disease (NAFLD), diabetes mellitus, and obesity, among others. Although pre-clinical models have been investigated to mimic the transition from NAFLD to HCC, they do not accurately reproduce the phenotypic evolution from simple steatosis to steatohepatitis, fibrosis/cirrhosis, and HCC. Hence, these models have failed to demonstrate the influence of diabetes on hepatic carcinogenesis. Here, we report a novel mouse model of HCC triggered by fast-developing diabetes and NAFLD. The first step consists in a single intraperitoneal injection of a low dose of streptozotocin into neonatal C57BL/6J mice to induce type 2 diabetes. In a second step, mice are fed with high-fat diet to accelerate the development of simple steatosis. Continuous high-fat diet exacerbates hepatic fat deposition with increased lobular inflammation (by activation of foam cell-like macrophages) and fibrosis (by activating hepatic stellate cells), two representative pathological traits of steatohepatitis/fibrosis. After 20 weeks, all mice developed multiple HCCs. This model of hepatic carcinogenesis triggered by diabetes mellitus and NAFLD offers the advantage of being rapid and accurately recapitulates the pathogenesis of human HCC without the need of administering hepatic carcinogens.


Subject(s)
Carcinoma, Hepatocellular , Diabetes Mellitus, Type 2 , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Humans , Mice , Animals , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/pathology , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/pathology , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Streptozocin , Diet, High-Fat/adverse effects , Diabetes Mellitus, Type 2/pathology , Mice, Inbred C57BL , Liver/pathology , Disease Models, Animal , Liver Cirrhosis/pathology , Carcinogenesis/pathology
16.
Methods Mol Biol ; 2769: 109-128, 2024.
Article in English | MEDLINE | ID: mdl-38315393

ABSTRACT

In the early stages of liver carcinogenesis, rare hepatocytes and cholangiocytes are transformed into preneoplastic cells, which can progressively acquire a neoplastic phenotype, favored by the failure of natural antitumor immunosurveillance. The detailed study of both hepatic parenchymal (e.g., hepatocytes) and non-parenchymal cells (NPCs), such as immune cells, could help understand the cellular microenvironment surrounding these pre-cancerous and neoplastic lesions.Cultures of primary hepatocytes are of interest in various biomedical research disciplines, serving as an ex vivo model for liver physiology. Obtaining high viability and yield of primary mouse hepatocytes and other liver cell populations is technically challenging, thus limiting their use. In the first section of the current chapter, we introduce a protocol based on the two-step collagenase perfusion technique (by inferior vena cava) to isolate hepatocytes and, to a lower extent, NPCs and detailed the different considerations to take into account for a successful perfusion. The liver is washed by perfusion, hepatocytes are dissociated with collagenase, and different cell populations are separated by centrifugation. Various techniques have been described for the isolation of healthy and malignant hepatocytes; however, the viability and purity of the isolated cells is frequently not satisfactory. Here, we significantly optimized this protocol to reach improved yield and viability of the hepatocytes and concomitantly obtain preserved NPC populations of the liver.Within NPCs, tissue-resident or recruited immune cells are essential actors regulating hepatocarcinogenesis. However, simultaneous isolation of hepatic leukocytes together with other cell types generally yields low immune cell numbers hindering downstream application with these cells. In the second section of this chapter, as opposed to the first section primarily aiming to isolate hepatocytes, we present a tissue dissociation protocol adapted to efficiently recover leukocytes from non-perfused bulk (pre-)cancerous livers. This protocol has been optimized to be operator-friendly and fast compared to other liver processing methods, allowing easy simultaneous sample processing to retrieve hepatic (tumor-infiltrating) immune cells.


Subject(s)
Liver , Precancerous Conditions , Mice , Animals , Cell Separation/methods , Hepatocytes , Carcinogenesis , Collagenases , Tumor Microenvironment
17.
Food Funct ; 15(12): 6304-6323, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38812411

ABSTRACT

The global prevalence of cancer continues to increase, so does its mortality. Strategies that can prevent/treat this condition are therefore required, especially low-cost and low-toxicity strategies. Bioactive compounds of plant origin have been presented as a good alternative. In this scenario, due to its abundant polyphenolic content (around 60 to 120 times greater than that of the grain), peanut skin by-products stand out as a sustainable source of food bioactives beneficial to human health. Investigated studies highlighted the importance of peanut skin for human health, its phytochemical composition, bioactivity and the potential for prevention and/or adjuvant therapy in cancer, through the advanced search for articles in the Virtual Health Library (VHL), Science direct and the Mourisco platform of the FioCruz Institute, from 2012 to 2022. Using the keywords, "peanut skin" AND "cancer" AND NOT "allergy", the words "peanut testa" and "peanut peel" were included replacing "peanut skin". 18 articles were selected from Plataforma Mourisco, 26 from Science Direct and 26 from VHL. Of these, 7 articles evaluated aspects of cancer prevention and/or treatment. Promising benefits were found in the prevention/treatment of chronic non-communicable diseases in the use of peanut and peanut skin extracts, such as cholesterolemia and glucose control, attenuation of oxidative stress and suppressive action on the proliferation and metabolism of cancer cells.


Subject(s)
Arachis , Humans , Arachis/chemistry , Plant Extracts/pharmacology , Noncommunicable Diseases/prevention & control , Phytochemicals/pharmacology , Chronic Disease/prevention & control , Neoplasms/prevention & control , Animals
18.
Methods Mol Biol ; 2769: 189-198, 2024.
Article in English | MEDLINE | ID: mdl-38315398

ABSTRACT

The metabolic rearrangements of hepatic metabolism associated with liver cancer are still incompletely understood. There is an ongoing need to identify novel and more efficient diagnostic biomarkers and therapeutic targets based on the metabolic mechanisms of these diseases. In comparison to traditional diagnostic biomarkers, metabolomics is a comprehensive technique for discovering chemical signatures for liver cancer screening, prediction, and earlier diagnosis. Lipids are a large and diverse group of complex biomolecules that are at the heart of liver physiology and play an important role in the development and progression of cancer. In this chapter, we described two detailed protocols for targeted lipids analysis: glycerophospholipids and mono, di, tri-acylglycerides, both by Flow Injection Analysis (FIA) HPLC coupled to a SelexIon/QTRAP 6500+ system. These approaches provide a targeted lipidomic metabolomic signature of dissimilar metabolic disorders affecting liver cancers.


Subject(s)
Glycerophospholipids , Liver Neoplasms , Humans , Metabolomics/methods , Biomarkers
19.
Methods Mol Biol ; 2769: 199-209, 2024.
Article in English | MEDLINE | ID: mdl-38315399

ABSTRACT

Liver cancers are characterized by interindividual and intratumoral heterogeneity, which makes early diagnosis and the development of therapies challenging. Desorption electrospray ionization mass spectrometry (DESI-MS) imaging is a potent and sensitive MS ionization technique for direct, unaltered 2D and 3D imaging of metabolites in complex biological samples. Indeed, DESI gently desorbs and ionizes analyte molecules from the sample surface using an electrospray source of highly charged aqueous spray droplets in ambient conditions. DESI-MS imaging of biological samples allows untargeted analysis and characterization of metabolites in liver cancers to identify new biomarkers of malignancy. In this chapter, we described a detailed protocol using liver cancer samples collected and stored for histopathology examination, either as frozen or as formalin-fixed, paraffin-embedded specimens. Such hepatocellular carcinoma samples can be subjected to DESI-MS analyses, illustrating the capacity of spatially resolved metabolomics to distinguish malignant lesions from adjacent normal liver tissue.


Subject(s)
Liver Neoplasms , Spectrometry, Mass, Electrospray Ionization , Humans , Spectrometry, Mass, Electrospray Ionization/methods , Metabolomics , Liver Neoplasms/diagnostic imaging , Biomarkers
20.
Cell Death Dis ; 15(4): 249, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38582872

ABSTRACT

Acyl-CoA binding protein (ACBP) encoded by diazepam binding inhibitor (DBI) is an extracellular inhibitor of autophagy acting on the gamma-aminobutyric acid A receptor (GABAAR) γ2 subunit (GABAARγ2). Here, we show that lipoanabolic diets cause an upregulation of GABAARγ2 protein in liver hepatocytes but not in other major organs. ACBP/DBI inhibition by systemically injected antibodies has been demonstrated to mediate anorexigenic and organ-protective, autophagy-dependent effects. Here, we set out to develop a new strategy for developing ACBP/DBI antagonists. For this, we built a molecular model of the interaction of ACBP/DBI with peptides derived from GABAARγ2. We then validated the interaction between recombinant and native ACBP/DBI protein and a GABAARγ2-derived eicosapeptide (but not its F77I mutant) by pull down experiments or surface plasmon resonance. The GABAARγ2-derived eicosapeptide inhibited the metabolic activation of hepatocytes by recombinant ACBP/DBI protein in vitro. Moreover, the GABAARγ2-derived eicosapeptide (but not its F77I-mutated control) blocked appetite stimulation by recombinant ACBP/DBI in vivo, induced autophagy in the liver, and protected mice against the hepatotoxin concanavalin A. We conclude that peptidomimetics disrupting the interaction between ACBP/DBI and GABAARγ2 might be used as ACBP/DBI antagonists. This strategy might lead to the future development of clinically relevant small molecules of the ACBP/DBI system.


Subject(s)
Diazepam Binding Inhibitor , gamma-Aminobutyric Acid , Animals , Mice , Diazepam Binding Inhibitor/pharmacology
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