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1.
Sci Rep ; 14(1): 2488, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291121

RESUMEN

Bladder cancer is one of the most common cancer types in the urinary system. Yet, current bladder cancer diagnosis and follow-up techniques are time-consuming, expensive, and invasive. In the clinical practice, the gold standard for diagnosis remains invasive biopsy followed by histopathological analysis. In recent years, costly diagnostic tests involving the use of bladder cancer biomarkers have been developed, however these tests have high false-positive and false-negative rates limiting their reliability. Hence, there is an urgent need for the development of cost-effective, and non-invasive novel diagnosis methods. To address this gap, here we propose a quick, cheap, and reliable diagnostic method. Our approach relies on an artificial intelligence (AI) model to analyze droplet patterns of blood and urine samples obtained from patients and comparing them to cancer-free control subjects. The AI-assisted model in this study uses a deep neural network, a ResNet network, pre-trained on ImageNet datasets. Recognition and classification of complex patterns formed by dried urine or blood droplets under different conditions resulted in cancer diagnosis with a high specificity and sensitivity. Our approach can be systematically applied across droplets, enabling comparisons to reveal shared spatial behaviors and underlying morphological patterns. Our results support the fact that AI-based models have a great potential for non-invasive and accurate diagnosis of malignancies, including bladder cancer.


Asunto(s)
Inteligencia Artificial , Neoplasias de la Vejiga Urinaria , Humanos , Reproducibilidad de los Resultados , Neoplasias de la Vejiga Urinaria/patología , Vejiga Urinaria/patología , Biomarcadores de Tumor/orina
2.
Autophagy ; 19(1): 306-323, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35722965

RESUMEN

Macroautophagy/autophagy is an evolutionarily conserved cellular stress response mechanism. Autophagy induction in the tumor microenvironment (stroma) has been shown to support tumor metabolism. However, cancer cell-derived secreted factors that initiate communication with surrounding cells and stimulate autophagy in the tumor microenvironment are not fully documented. We identified CTF1/CT-1 (cardiotrophin 1) as an activator of autophagy in fibroblasts and breast cancer-derived carcinoma-associated fibroblasts (CAFs). We showed that CTF1 stimulated phosphorylation and nuclear translocation of STAT3, initiating transcriptional activation of key autophagy proteins. Additionally, following CTF1 treatment, AMPK and ULK1 activation was observed. We provided evidence that autophagy was important for CTF1-dependent ACTA2/α-SMA accumulation, stress fiber formation and fibroblast activation. Moreover, promotion of breast cancer cell migration and invasion by activated fibroblasts depended on CTF1 and autophagy. Analysis of the expression levels of CTF1 in patient-derived breast cancer samples led us to establish a correlation between CTF1 expression and autophagy in the tumor stroma. In line with our in vitro data on cancer migration and invasion, higher levels of CTF1 expression in breast tumors was significantly associated with lymph node metastasis in patients. Therefore, CTF1 is an important mediator of tumor-stroma interactions, fibroblast activation and cancer metastasis, and autophagy plays a key role in all these cancer-related events.Abbreviations: ACTA2/α-SMA: actin, alpha 2, smooth muscle CAFs: cancer- or carcinoma-associated fibroblasts CNT Ab.: control antibody CNTF: ciliary neurotrophic factor CTF1: cardiotrophin 1 CTF1 Neut. Ab.: CTF1-specific neutralizing antibody GFP-LC3 MEF: GFP-fused to MAP1LC3 protein transgenic MEF LIF: leukemia inhibitory factor IL6: interleukin 6 MEFs: mouse embryonic fibroblasts MEF-WT: wild-type MEFs OSM: oncostatin M TGFB/TGFß: transforming growth factor beta.


Asunto(s)
Autofagia , Neoplasias de la Mama , Citocinas , Animales , Ratones , Línea Celular Tumoral , Movimiento Celular , Fibroblastos/metabolismo , Interleucina-6/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Humanos , Femenino , Neoplasias de la Mama/metabolismo , Citocinas/metabolismo
3.
Front Cell Dev Biol ; 11: 1274682, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38234683

RESUMEN

Tumors not only consist of cancerous cells, but they also harbor several normal-like cell types and non-cellular components. cancer-associated fibroblasts (CAFs) are one of these cellular components that are found predominantly in the tumor stroma. Autophagy is an intracellular degradation and quality control mechanism, and recent studies provided evidence that autophagy played a critical role in CAF formation, metabolic reprograming and tumor-stroma crosstalk. Therefore, shedding light on the autophagy and its role in CAF biology might help us better understand the roles of CAFs and the TME in cancer progression and may facilitate the exploitation of more efficient cancer diagnosis and treatment. Here, we provide an overview about the involvement of autophagy in CAF-related pathways, including transdifferentiation and activation of CAFs, and further discuss the implications of targeting tumor stroma as a treatment option.

4.
OMICS ; 26(5): 270-279, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35394340

RESUMEN

A major problem in medicine and oncology is cancer recurrence through the activation of dormant cancer cells. A system scale examination of metabolic dysregulations associated with the cancer dormancy offers promise for the discovery of novel molecular targets for cancer precision medicine, and importantly, for the prevention of cancer recurrence. In this study, we mapped the total mRNA sequencing-based transcriptomic data from dormant cancer cell lines and nondormant cancer controls onto a human genome-scale metabolic network by using a graph-based approach, and two mass balance-based approaches with one based on reaction activity/inactivity and the other one on flux changes. The gene expression datasets were accessed from Gene Expression Omnibus (GSE83142 and GSE114012). This analysis included two diverse cancer types, a liquid and a solid cancer, namely, acute lymphoblastic leukemia and colorectal cancer. For the dormant cancer state, we observed changes in major adenosine triphosphate-producing pathways, including the citric acid cycle, oxidative phosphorylation, and glycolysis/gluconeogenesis, indicating a reprogramming in the metabolism of dormant cells away from Warburg-based energy metabolism. All three computational approaches unanimously predicted that folate metabolism, pyruvate metabolism, and glutamate metabolism, as well as valine/leucine/isoleucine metabolism are likely dysregulated in cancer dormancy. These findings provide new insights and molecular pathway targets on cancer dormancy, comprehensively catalog dormancy-associated metabolic pathways, and inform future research aimed at prevention of cancer recurrence in particular.


Asunto(s)
Neoplasias , Transcriptoma , Humanos , Redes y Vías Metabólicas/genética , Neoplasias/genética , Transcriptoma/genética
5.
J Gastrointest Cancer ; 52(4): 1277-1293, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34921672

RESUMEN

The goal of successful cancer treatment is targeting the eradication of cancer cells. Although surgical removal of the primary tumors and several rounds of chemo- and radiotherapy reduce the disease burden, in some cases, asymptomatic dormant cancer cells may still exist in the body. Dormant cells arise from the disseminated tumor cells (DTCs) from the primary lesion. DTCs escape from immune system and cancer therapy and reside at the secondary organ without showing no sign of proliferation. However, under some conditions. dormant cells can be re-activated and enter a proliferative state even after decades. As a stress response mechanism, autophagy may help the adaptation of DTCs at this futile foreign microenvironment and may control the survival and re-activation of dormant cells. Studies indicate that hepatic microenvironment serves a favorable condition for cancer cell dormancy. Although, no direct study was pointing out the role of autophagy in liver-assisted dormancy, involvement of autophagy in both liver microenvironment, health, and disease conditions has been indicated. Therefore, in this review article, we will summarize cancer dormancy and discuss the role and importance of autophagy and hepatic microenvironment in this context.


Asunto(s)
Autofagia/fisiología , Neoplasias Hepáticas/metabolismo , Neoplasia Residual/metabolismo , Microambiente Tumoral/fisiología , Animales , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Neoplasias Hepáticas/fisiopatología , Masculino , Ratones , Metástasis de la Neoplasia/fisiopatología
6.
Turk J Biol ; 45(3): 235-252, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34377049

RESUMEN

Autophagy and DNA repair are two essential biological mechanisms that maintain cellular homeostasis. Impairment of these mechanisms was associated with several pathologies such as premature aging, neurodegenerative diseases, and cancer. Intrinsic or extrinsic stress stimuli (e.g., reactive oxygen species or ionizing radiation) cause DNA damage. As a biological stress response, autophagy is activated following insults that threaten DNA integrity. Hence, in collaboration with DNA damage repair and response mechanisms, autophagy contributes to the maintenance of genomic stability and integrity. Yet, connections and interactions between these two systems are not fully understood. In this review article, current status of the associations and crosstalk between autophagy and DNA repair systems is documented and discussed.

7.
Sci Rep ; 11(1): 15806, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34349126

RESUMEN

Primary cancer cells exert unique capacity to disseminate and nestle in distant organs. Once seeded in secondary sites, cancer cells may enter a dormant state, becoming resistant to current treatment approaches, and they remain silent until they reactivate and cause overt metastases. To illuminate the complex mechanisms of cancer dormancy, 10 transcriptomic datasets from the literature enabling 21 dormancy-cancer comparisons were mapped on protein-protein interaction networks and gene-regulatory networks to extract subnetworks that are enriched in significantly deregulated genes. The genes appearing in the subnetworks and significantly upregulated in dormancy with respect to proliferative state were scored and filtered across all comparisons, leading to a dormancy-interaction network for the first time in the literature, which includes 139 genes and 1974 interactions. The dormancy interaction network will contribute to the elucidation of cellular mechanisms orchestrating cancer dormancy, paving the way for improvements in the diagnosis and treatment of metastatic cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Biología Computacional/métodos , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Neoplasias/genética , Lesiones Precancerosas/genética , Transcriptoma , Animales , Biomarcadores de Tumor/metabolismo , Humanos , Ratones , Neoplasias/metabolismo , Neoplasias/patología , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología
8.
Front Oncol ; 11: 627023, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33816262

RESUMEN

Metastasis and relapse account for the great majority of cancer-related deaths. Most metastatic lesions are micro metastases that have the capacity to remain in a non-dividing state called "dormancy" for months or even years. Commonly used anticancer drugs generally target actively dividing cancer cells. Therefore, cancer cells that remain in a dormant state evade conventional therapies and contribute to cancer recurrence. Cellular and molecular mechanisms of cancer dormancy are not fully understood. Recent studies indicate that a major cellular stress response mechanism, autophagy, plays an important role in the adaptation, survival and reactivation of dormant cells. In this review article, we will summarize accumulating knowledge about cellular and molecular mechanisms of cancer dormancy, and discuss the role and importance of autophagy in this context.

9.
Methods Mol Biol ; 2207: 199-220, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33113138

RESUMEN

Ceranib-2 is a recently discovered, poorly water-soluble potent ceramidase inhibitor, with the ability to suppress cancer cell proliferation and delay tumor growth. However, its poor water solubility and weak cellular bioavailability hinder its use as a therapeutic agent for cancer. PEGylated rosin esters are an excellent platform as a natural polymer for drug delivery applications, especially for controlling drug release due to their degradability, biocompatibility, capability to improve solubility, and pharmacokinetics of potent drugs. In this study, stable aqueous amphiphilic submicron-sized PEG400-rosin ester-ceranib-2 (PREC-2) particles, ranging between 100 and 350 nm in a 1:1 mixture, were successfully synthesized by solvent evaporation mediated by sonication.Conclusion: Stable aqueous PEGylated rosin ester nanocarriers might present a significant solution to improve solubility, pharmacokinetic, and bioavailability of ceranib-2, and hold promises for use as an anticancer adjacent drug after further investigations.


Asunto(s)
Antineoplásicos , Portadores de Fármacos , Neoplasias , Polietilenglicoles/química , Quinolonas , Resinas de Plantas/química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Células HeLa , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Quinolonas/química , Quinolonas/farmacocinética , Quinolonas/farmacología
10.
Langmuir ; 36(33): 9728-9737, 2020 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-32787115

RESUMEN

A sessile droplet of a complex fluid exhibits several stages of drying leading to the formation of a final pattern on the substrate. We report such pattern formation in dehydrating droplets of protein (BSA) and salts (MgCl2 and KCl) at various concentrations of the two components (protein and salts) as part of a parametric study for the understanding of complex patterns of dehydrating biofluid droplets (blood and urine), which will eventually be used for diagnosis of bladder cancer. The exact analysis of the biofluid patterns will require a rigorous parametric study; however, the current work provides an initial understanding of the effect of the basic components present in a biofluid droplet. Arrangement of the protein and the salts, due to evaporation, leads to the formation of some very distinctive final structures at the end of the droplet lifetime. Furthermore, these structures can be manipulated by varying the initial ratio of the two components in the solution. MgCl2 forms chains of crystals beyond a threshold initial concentration of protein (>3 wt %). However, the formation of such a crystal is also limited by the maximum concentration of the salt initially present in the droplet (≤1 wt %). On the other hand, KCl forms dendritic and rectangular crystals in the presence of BSA. The formation of these crystals also depends on the relative concentration of salt and protein in the droplet. We also investigated the dried-out patterns in dehydrating droplets of mixed salts (MgCl2 + KCl) and protein. The patterns can be tuned from a continuous dendritic structure to a snow-flake type structure just by altering the initial ratio of the two salts in the mixture, keeping all other parameters constant.


Asunto(s)
Sales (Química) , Cloruro de Sodio , Desecación , Proteínas
11.
J Nanobiotechnology ; 18(1): 65, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32345308

RESUMEN

Nanoparticle based gene delivery systems holds great promise. Superparamagnetic iron oxide nanoparticles (SPIONs) are being heavily investigated due to good biocompatibility and added diagnostic potential, rendering such nanoparticles theranostic. Yet, commonly used cationic coatings for efficient delivery of such anionic cargos, results in significant toxicity limiting translation of the technology to the clinic. Here, we describe a highly biocompatible, small and non-cationic SPION-based theranostic nanoparticles as novel gene therapy agents. We propose for the first-time, the usage of the microRNA machinery RISC complex component Argonaute 2 (AGO2) protein as a microRNA stabilizing agent and a delivery vehicle. In this study, AGO2 protein-conjugated, anti-HER2 antibody-linked and fluorophore-tagged SPION nanoparticles were developed (SP-AH nanoparticles) and used as a carrier for an autophagy inhibitory microRNA, MIR376B. These functionalized nanoparticles selectively delivered an effective amount of the microRNA into HER2-positive breast cancer cell lines in vitro and in a xenograft nude mice model of breast cancer in vivo, and successfully blocked autophagy. Furthermore, combination of the chemotherapy agent cisplatin with MIR376B-loaded SP-AH nanoparticles increased the efficacy of the anti-cancer treatment both in vitro in cells and in vivo in the nude mice. Therefore, we propose that AGO2 protein conjugated SPIONs are a new class of theranostic nanoparticles and can be efficiently used as innovative, non-cationic, non-toxic gene therapy tools for targeted therapy of cancer.


Asunto(s)
Proteínas Argonautas/química , Autofagia , Materiales Biocompatibles/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Nanopartículas de Magnetita/química , MicroARNs/metabolismo , Animales , Anticuerpos/química , Anticuerpos/inmunología , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Autofagia/efectos de los fármacos , Beclina-1/genética , Beclina-1/metabolismo , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Cisplatino/química , Cisplatino/uso terapéutico , Femenino , Humanos , Ratones , Ratones Desnudos , MicroARNs/química , Receptor ErbB-2/inmunología , Trasplante Heterólogo
12.
Biochim Biophys Acta Mol Cell Res ; 1867(5): 118662, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32001304

RESUMEN

Autophagy is a cellular stress response mechanism activation of which leads to degradation of cellular components, including proteins as well as damaged organelles in lysosomes. Defects in autophagy mechanisms were associated with several pathologies (e.g. cancer, neurodegenerative diseases, and rare genetic diseases). Therefore, autophagy regulation is under strict control. Transcriptional and post-translational mechanisms that control autophagy in cells and organisms studied in detail. Recent studies introduced non-coding small RNAs, and especially microRNAs (miRNAs) in the post-translational orchestration of the autophagic activity. In this review article, we analyzed in detail the current status of autophagy-miRNA connections. Comprehensive documentation of miRNAs that were directly involved in autophagy regulation resulted in the emergence of common themes and concepts governing these complex and intricate interactions. Hence, a better and systematic understanding of these interactions reveals a central role for miRNAs in the regulation of autophagy.


Asunto(s)
Redes Reguladoras de Genes , MicroARNs/genética , Autofagia , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos
13.
J Mater Chem B ; 7(46): 7363-7376, 2019 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-31696188

RESUMEN

Targeted drug delivery systems that combine imaging and therapeutic functions in a single structure have become very popular in nanomedicine. Near-infrared (NIR) emitting Ag2S quantum dots (QDs) are excellent candidates for this task. Here, we have developed PEGylated Ag2S QDs functionalized with Cetuximab (Cet) antibody and loaded with an anticancer drug, 5-fluorouracil (5FU). These theranostic QDs were used for targeted NIR imaging and treatment of lung cancer using low (H1299) and high (A549) Epidermal Growth Factor Receptor (EGFR) overexpressing cell lines. The Cet conjugated QDs effectively and selectively delivered 5FU to A549 cells and provided significantly enhanced cell death associated with apoptosis. Interestingly, while treatment of cells with free 5FU activated autophagy, a cellular mechanism conferring resistance to cell death, these EGFR targeting multimodal QDs significantly overcame drug resistance compared to 5FU treatment alone. The improved therapeutic outcome of 5FU delivered to A549 cells by Cet conjugated Ag2S QDs is suggested as the synergistic outcome of enhanced receptor mediated uptake of nanoparticles, and hence the drug, coupled with suppressed autophagy even in the absence of addition of an autophagy suppressor.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Resistencia a Antineoplásicos , Fluorouracilo/administración & dosificación , Neoplasias Pulmonares/metabolismo , Compuestos de Plata/química , Células A549 , Autofagia , Muerte Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cetuximab/administración & dosificación , Receptores ErbB/genética , Humanos , Imidazoles/química , Neoplasias Pulmonares/tratamiento farmacológico , Polietilenglicoles/química , Puntos Cuánticos , Nanomedicina Teranóstica
14.
ACS Omega ; 4(7): 12366-12374, 2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-31460354

RESUMEN

Gene therapy is a developing method for the treatment of various diseases. For this purpose, the search for nonviral methods has recently accelerated to avoid toxic effects. A strong alternative method is magnetofection, which involves the use of superparamagnetic iron oxide nanoparticles (SPIONs) with a proper organic coating and external magnetic field to enhance the localization of SPIONs at the target site. In this study, a new magnetic actuation system consisting of four rare-earth magnets on a rotary table was designed and manufactured to obtain improved magnetofection. As a model, green fluorescent protein DNA-bearing polyethyleneimine-coated SPIONs were used. Magnetofection was tested on MCF7 cells. The system reduced the transfection time (down to 1 h) of the standard polyethyleneimine transfection protocol. As a result, we showed that the system could be effectively used for gene transfer.

15.
Eur J Pharm Sci ; 134: 116-137, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30981885

RESUMEN

Autophagy is an evolutionarily conserved catabolic mechanism, by which eukaryotic cells recycle or degrades internal constituents through membrane-trafficking pathway. Thus, autophagy provides the cells with a sustainable source of biomolecules and energy for the maintenance of homeostasis under stressful conditions such as tumor microenvironment. Recent findings revealed a close relationship between autophagy and malignant transformation. However, due to the complex dual role of autophagy in tumor survival or cell death, efforts to develop efficient treatment strategies targeting the autophagy/cancer relation have largely been unsuccessful. Here we review the two-faced role of autophagy in cancer as a tumor suppressor or as a pro-oncogenic mechanism. In this sense, we also review the shared regulatory pathways that play a role in autophagy and malignant transformation. Finally, anti-cancer therapeutic agents used as either inhibitors or inducers of autophagy have been discussed.


Asunto(s)
Autofagia/efectos de los fármacos , Autofagia/fisiología , Neoplasias/metabolismo , Animales , Antineoplásicos , Genes Supresores de Tumor , Humanos , Terapia Molecular Dirigida , Neoplasias/terapia , Oncogenes , Microambiente Tumoral
16.
J Dermatol Sci ; 93(1): 50-57, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30655104

RESUMEN

BACKGROUND: Autosomal Recessive Congenital Ichthyosis (ARCI) is a group of epidermal keratinization disorders. One of the disease-associated proteins, patatin-like phospholipase domain-containing protein-1 (PNPLA1), plays a key role in the epidermal omega-O-acylceramide synthesis and localizes on the surface of lipid droplets (LDs). OBJECTIVE: Previously, routine clinical test results showed abnormal LD accumulation in blood smear samples of our ARCI patients with PNPLA1 mutations. To investigate the abnormal accumulation of LDs, we analyzed primary fibroblast cells of ARCI patients with PNPLA1 mutations (p.Y245del and p.D172N). We hypothesized that PNPLA1 mutations might affect lipophagy-mediated regulation of LDs and cause intracellular lipid accumulation in ARCI patients. METHODS: LD accumulation was analyzed by fluorescence staining with BODIPY®493/503 in the fibroblasts of patient cells and PNPLA1 siRNA transfected control fibroblast cells. The expression of PNPLA1 and its effects on the lipophagy-mediated degradation of LDs were analyzed by immunocytochemistry and immunoblotting. RESULTS: Our results showed that mutant or downregulated PNPLA1 protein causes abnormal intracellular LD accumulation. We found that PNPLA1 mutations affect neither the cellular localization nor the expression levels of the protein in fibroblast cells. When we analyzed lipophagic degradation process, LC3 expression and the number of autophagosomes were significantly decreased in fibroblast cells of the patients. In addition, co-localization of LDs with autophagosomes and lysosomes were markedly less than that of the control group. CONCLUSION: PNPLA1 mutations caused disturbances in both autophagosome formation and fusion of autophagosomes with lysosomes. Our results indicate a possible role for PNPLA1 protein in LD regulation via lipophagy-mediated degradation.


Asunto(s)
Autofagia/genética , Ictiosis Lamelar/patología , Lipasa/genética , Gotas Lipídicas/patología , Piel/patología , Autofagosomas/patología , Biopsia , Fibroblastos/citología , Fibroblastos/patología , Genes Recesivos , Humanos , Ictiosis Lamelar/genética , Lisosomas/patología , Mutación , Cultivo Primario de Células , ARN Interferente Pequeño/metabolismo , Piel/citología
17.
Methods Mol Biol ; 1854: 131-146, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29022289

RESUMEN

Autophagy is a cellular survival pathway that is necessary for the degradation of cellular constituents such as long-lived proteins and damaged organelles. Conditions resulting in cellular stress such as starvation or hypoxia might activate autophagy. Being at the crossroads of various cellular response pathways, dysregulation of autophagy might result in pathological states including cancer and neurodegenerative diseases. Autophagy has also been shown to participate in stemness. MicroRNAs were introduced as novel regulators of autophagy, and accumulating results underlined the fact that they constituted an important layer of biological control mechanism on the autophagic activity.MicroRNAs are protein noncoding small RNAs that control cellular levels of transcripts and proteins through posttrancriptional mechanisms. Novel miRNAs in human and mouse genomes are yet to be identified. Considering the emerging role of autophagy in health and disease, identification of novel autophagy-regulating miRNAs and determination of relations between miRNA expression and physiological and pathological conditions might contribute to a better understanding of mechanisms governing health and disease. High-throughput techniques were developed for miRNA profiling, yet for a thorough characterization and miRNA target determination, miRNA cloning remains as an important step. Here, we describe a modified miRNA cloning method for the characterization of novel autophagy-regulating miRNAs.


Asunto(s)
Autofagia , Clonación Molecular/métodos , MicroARNs/genética , Animales , Proteínas Relacionadas con la Autofagia/genética , Células Cultivadas , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones
18.
Autophagy ; 15(3): 375-390, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30290719

RESUMEN

Macroautophagy (autophagy) is an evolutionarily conserved recycling and stress response mechanism. Active at basal levels in eukaryotes, autophagy is upregulated under stress providing cells with building blocks such as amino acids. A lysosome-integrated sensor system composed of RRAG GTPases and MTOR complex 1 (MTORC1) regulates lysosome biogenesis and autophagy in response to amino acid availability. Stress-mediated inhibition of MTORC1 results in the dephosphorylation and nuclear translocation of the TFE/MITF family of transcriptional factors, and triggers an autophagy- and lysosomal-related gene transcription program. The role of family members TFEB and TFE3 have been studied in detail, but the importance of MITF proteins in autophagy regulation is not clear so far. Here we introduce for the first time a specific role for MITF in autophagy control that involves upregulation of MIR211. We show that, under stress conditions including starvation and MTOR inhibition, a MITF-MIR211 axis constitutes a novel feed-forward loop that controls autophagic activity in cells. Direct targeting of the MTORC2 component RICTOR by MIR211 led to the inhibition of the MTORC1 pathway, further stimulating MITF translocation to the nucleus and completing an autophagy amplification loop. In line with a ubiquitous function, MITF and MIR211 were co-expressed in all tested cell lines and human tissues, and the effects on autophagy were observed in a cell-type independent manner. Thus, our study provides direct evidence that MITF has rate-limiting and specific functions in autophagy regulation. Collectively, the MITF-MIR211 axis constitutes a novel and universal autophagy amplification system that sustains autophagic activity under stress conditions. Abbreviations: ACTB: actin beta; AKT: AKT serine/threonine kinase; AKT1S1/PRAS40: AKT1 substrate 1; AMPK: AMP-activated protein kinase; ATG: autophagy-related; BECN1: beclin 1; DEPTOR: DEP domain containing MTOR interacting protein; GABARAP: GABA type A receptor-associated protein; HIF1A: hypoxia inducible factor 1 subunit alpha; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAPKAP1/SIN1: mitogen-activated protein kinase associated protein 1; MITF: melanogenesis associated transcription factor; MLST8: MTOR associated protein, LST8 homolog; MRE: miRNA response element; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; MTORC2: MTOR complex 2; PRR5/Protor 1: proline rich 5; PRR5L/Protor 2: proline rich 5 like; RACK1: receptor for activated C kinase 1; RPTOR: regulatory associated protein of MTOR complex 1; RICTOR: RPTOR independent companion of MTOR complex 2; RPS6KB/p70S6K: ribosomal protein S6 kinase; RT-qPCR: quantitative reverse transcription-polymerase chain reaction; SQSTM1: sequestosome 1; STK11/LKB1: serine/threonine kinase 11; TFE3: transcription factor binding to IGHM enhancer 3; TFEB: transcription factor EB; TSC1/2: TSC complex subunit 1/2; ULK1: unc-51 like autophagy activating kinase 1; UVRAG: UV radiation resistance associated; VIM: vimentin; VPS11: VPS11, CORVET/HOPS core subunit; VPS18: VPS18, CORVET/HOPS core subunit; WIPI1: WD repeat domain, phosphoinositide interacting 1.


Asunto(s)
Autofagia/genética , MicroARNs/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Proteína Asociada al mTOR Insensible a la Rapamicina/metabolismo , Estrés Fisiológico/genética , Serina-Treonina Quinasas TOR/metabolismo , Autofagia/efectos de los fármacos , Inmunoprecipitación de Cromatina , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Factor de Transcripción Asociado a Microftalmía/genética , Proteína Asociada al mTOR Insensible a la Rapamicina/antagonistas & inhibidores , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
19.
Turk J Gastroenterol ; 29(3): 270-282, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29755011

RESUMEN

Autophagy is a key biological phenomenon conserved from yeast to mammals. Under basal conditions, activation of autophagy leads to the protein degradation as well as damaged organelles for maintaining cellular homeostasis. Deregulation of autophagy has been identified as a key mechanism contributing to the pathogenesis and progression of several liver diseases, including hepatocellular carcinoma (HCC), one of the most common and mortal types of cancer. Currently used treatment strategies in patients with HCC result in variable success rates. Therefore, novel early diagnosis and treatment techniques should be developed. Manipulation of autophagy may improve responses of cancer cell to treatments and provide novel targeted therapy options for HCC. In this review, we summarized how our understanding of autophagy-cell death connection may have an impact on HCC therapy.


Asunto(s)
Autofagia/fisiología , Carcinoma Hepatocelular/fisiopatología , Neoplasias Hepáticas/fisiopatología , Hígado/citología , Hepatocitos/fisiología , Humanos , Hígado/fisiopatología
20.
Cell Mol Biol Lett ; 23: 10, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29568313

RESUMEN

BACKGROUND: The majority of novel chemotherapeutics target the cell cycle, aiming to effect arrest and cause apoptosis. One such agent, 2-methoxyestradiol (2ME), has been shown to possess anticancer properties against numerous cancer types, both in vitro and in vivo. Despite its promise, 2ME has exhibited limitations, including low oral bioavailability and rapid hepatic enzymatic inactivation in vivo. A novel sulphamoylated estrogen analog, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16), was in silico-designed in our laboratory to overcome these issues. It was then synthesized by a pharmaceutical company and used in an in vitro antiproliferative effect study on a human cervical carcinoma (HeLa) cell line. RESULTS: Cell proliferation data obtained from the crystal violet assay and real-time cell analysis demonstrated that 0.2 µM of ESE-16 had a significant inhibitory effect on the HeLa cells 24 h post-exposure. Immunofluorescence showed that ESE-16 is a microtubule disruptor that causes cells to undergo a mitotic block. Qualitative morphological studies using polarization-optical transmitted light differential interference contrast (PlasDIC) and light microscopy revealed a decrease in cell density and an increase in the number of cells arrested in metaphase. After ESE-16 exposure, hallmarks of apoptosis were also observed, including membrane blebbing, chromatin condensation and the presence of apoptotic bodies. Flow cytometry provided quantitative results from cell cycle progression analysis, indicating cells undergoing apoptosis and cells in the G2/M phase of the cell cycle, confirming cell cycle arrest in metaphase after ESE-16 treatment. Quantification of the ESE-16-mediated upregulation of cyclin B in HeLa cells and spectrophotometric and flow cytometric confirmation of cell death via apoptosis further confirmed the substance's impact. CONCLUSION: ESE-16 exerts its antiproliferative effects through microtubule disruption, which induces a mitotic block culminating in apoptosis. This research provided information on ESE-16 as a potential antitumor agent and on cellular targets that could aid in the design of prospective microtubule-disrupting compounds. Further in vitro and in vivo investigations of this novel compound are needed.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma/tratamiento farmacológico , Estrenos/uso terapéutico , Sulfonamidas/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Apoptosis , Carcinoma/patología , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Femenino , Células HeLa , Humanos , Neoplasias del Cuello Uterino/patología
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