Oligosaccharyltransferase: A Gatekeeper of Health and Tumor Progression

Oligosaccharyltransferase (OST) is a multi-span membrane protein complex that catalyzes the addition of glycans to selected Asn residues within nascent polypeptides in the lumen of the endoplasmic reticulum. This process, termed N-glycosylation, is a fundamental post-translational protein modification that is involved in the quality control, trafficking of proteins, signal transduction, and cell-to-cell communication. Given these crucial roles, N-glycosylation is essential for homeostasis at the systemic and cellular levels, and a deficiency in genes that encode for OST subunits often results in the development of complex genetic disorders. A growing body of evidence has also demonstrated that the expression of OST subunits is cell context-dependent and is frequently altered in malignant cells, thus contributing to tumor cell survival and proliferation. Importantly, a recently developed inhibitor of OST has revealed this enzyme as a potential target for the treatment of incurable drug-resistant tumors. This review summarizes our current knowledge regarding the functions of OST in the light of health and tumor progression, and discusses perspectives on the clinical relevance of inhibiting OST as a tumor treatment.

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Exosome-Mediated Signaling in Epithelial to Mesenchymal Transition and Tumor Progression

Journal of Clinical Medicine ◽

10.3390/jcm8010026 ◽

2018 ◽

Vol 8 (1) ◽

pp. 26 ◽

Cited By ~ 23

Author(s):

Alice Conigliaro ◽

Carla Cicchini

Keyword(s):

Tumor Progression ◽

Intercellular Communication ◽

Epithelial To Mesenchymal Transition ◽

Current Knowledge ◽

Cell Communication ◽

Therapeutic Approaches ◽

Mesenchymal Transition ◽

Rna Molecules ◽

Dna And Rna

Growing evidence points to exosomes as key mediators of cell–cell communication, by transferring their specific cargo (e.g., proteins, lipids, DNA and RNA molecules) from producing to receiving cells. In cancer, the regulation of the exosome-mediated intercellular communication may be reshaped, inducing relevant changes in gene expression of recipient cells in addition to microenvironment alterations. Notably, exosomes may deliver signals able to induce the transdifferentiation process known as Epithelial-to-Mesenchymal Transition (EMT). In this review, we summarize recent findings on the role of exosomes in tumor progression and EMT, highlighting current knowledge on exosome-mediated intercellular communication in tumor-niche establishment, migration, invasion, and metastasis processes. This body of evidence suggests the relevance of taking into account exosome-mediated signaling and its multifaceted aspects to develop innovative anti-tumoral therapeutic approaches.

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Ovarian Carcinoma and Serous Effusions. Changing Views Regarding Tumor Progression and Review of Current Literature1

Analytical Cellular Pathology ◽

10.1155/2001/418547 ◽

2001 ◽

Vol 23 (3-4) ◽

pp. 107-128 ◽

Cited By ~ 23

Author(s):

Ben Davidson

Keyword(s):

Ovarian Carcinoma ◽

Tumor Progression ◽

Solid Tumors ◽

Current Knowledge ◽

Gynecological Cancer ◽

Mesothelial Cells ◽

Carcinoma Cells ◽

Malignant Cells ◽

Primary Tumors ◽

Ovarian Carcinoma Cells

Carcinoma of the ovary is the leading cause of death from gynecological cancer in western countries. Ovarian carcinoma is commonly associated with the accumulation of fluid containing malignant cells in the peritoneal, and not infrequently in the pleural cavity. The differentiation of these cells from reactive mesothelial cells is at times difficult. In addition, tumor progression in ovarian carcinoma and the biological characteristics of carcinoma cells in effusions compared to their counterparts in solid tumors are poorly understood. This review details the current knowledge regarding diagnostic and biologic aspects of effusion cytology, with emphasis on ovarian carcinoma. Results from our first studies of effusions are subsequently presented. These attempt to address several issues. First, to improve the diagnostic ability to detect cancer cells in effusions using antibodies designed for the differentiation of epithelial cells from mesothelial cells. Secondly, to study genotypic and phenotypic differences between ovarian carcinoma cells in effusions, solid primary tumors and metastatic lesions, as well as to compare malignant cells in peritoneal and pleural effusions. These studies of carbohydrate antigens, E‐cadherin complex and matrix metalloproteinases (MMP) attempted to evaluate whether ovarian carcinoma cells in effusions possess true metastatic properties, or are similar to the cells in primary tumors, thereby merely representing the result of a shedding process. Finally, the prognostic role of these molecules was studied in solid tumors from a patient cohort consisting of long‐ and short‐term survivors, followed for up to 20 years. Figure 1 on http://www.esacp.org/acp/2001/23‐3,4/davidson.htm.

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Neurotoxic and Neuroprotective Role of Exosomes in Parkinson’s Disease

Current Pharmaceutical Design ◽

10.2174/1381612825666191113103537 ◽

2020 ◽

Vol 25 (42) ◽

pp. 4510-4522 ◽

Cited By ~ 5

Author(s):

Biancamaria Longoni ◽

Irene Fasciani ◽

Shivakumar Kolachalam ◽

Ilaria Pietrantoni ◽

Francesco Marampon ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Potential Role ◽

Current Knowledge ◽

Biological Fluids ◽

Cell Communication ◽

Target Cells ◽

Cellular Debris ◽

The Brain

: Exosomes are extracellular vesicles produced by eukaryotic cells that are also found in most biological fluids and tissues. While they were initially thought to act as compartments for removal of cellular debris, they are now recognized as important tools for cell-to-cell communication and for the transfer of pathogens between the cells. They have attracted particular interest in neurodegenerative diseases for their potential role in transferring prion-like proteins between neurons, and in Parkinson’s disease (PD), they have been shown to spread oligomers of α-synuclein in the brain accelerating the progression of this pathology. A potential neuroprotective role of exosomes has also been equally proposed in PD as they could limit the toxicity of α-synuclein by clearing them out of the cells. Exosomes have also attracted considerable attention for use as drug vehicles. Being nonimmunogenic in nature, they provide an unprecedented opportunity to enhance the delivery of incorporated drugs to target cells. In this review, we discuss current knowledge about the potential neurotoxic and neuroprotective role of exosomes and their potential application as drug delivery systems in PD.

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Aging of Bone Marrow Mesenchymal Stromal Cells: Hematopoiesis Disturbances and Potential Role in the Development of Hematologic Cancers

Cancers ◽

10.3390/cancers13010068 ◽

2020 ◽

Vol 13 (1) ◽

pp. 68

Author(s):

Fulvio Massaro ◽

Florent Corrillon ◽

Basile Stamatopoulos ◽

Nathalie Meuleman ◽

Laurence Lagneaux ◽

...

Keyword(s):

Bone Marrow ◽

Tumor Progression ◽

Cancer Progression ◽

Mesenchymal Stromal Cells ◽

Stromal Cells ◽

Cell Communication ◽

Bone Marrow Niche ◽

Hematopoietic Stem ◽

Wide Range ◽

Major Player

Aging of bone marrow is a complex process that is involved in the development of many diseases, including hematologic cancers. The results obtained in this field of research, year after year, underline the important role of cross-talk between hematopoietic stem cells and their close environment. In bone marrow, mesenchymal stromal cells (MSCs) are a major player in cell-to-cell communication, presenting a wide range of functionalities, sometimes opposite, depending on the environmental conditions. Although these cells are actively studied for their therapeutic properties, their role in tumor progression remains unclear. One of the reasons for this is that the aging of MSCs has a direct impact on their behavior and on hematopoiesis. In addition, tumor progression is accompanied by dynamic remodeling of the bone marrow niche that may interfere with MSC functions. The present review presents the main features of MSC senescence in bone marrow and their implications in hematologic cancer progression.

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Glucocorticoid Receptor β (GRβ): Beyond Its Dominant-Negative Function

International Journal of Molecular Sciences ◽

10.3390/ijms22073649 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3649

Author(s):

Patricia Ramos-Ramírez ◽

Omar Tliba

Keyword(s):

Current Knowledge ◽

Inflammatory Diseases ◽

Cell Communication ◽

Cell Types ◽

The Body ◽

Dominant Negative ◽

Negative Effects ◽

Independent Manner ◽

Distinct Cell ◽

Induced Apoptosis

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.

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Cell-to-Cell Communication by Host-Released Extracellular Vesicles in the Gut: Implications in Health and Disease

International Journal of Molecular Sciences ◽

10.3390/ijms22042213 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2213

Author(s):

Natalia Diaz-Garrido ◽

Cecilia Cordero ◽

Yenifer Olivo-Martinez ◽

Josefa Badia ◽

Laura Baldomà

Keyword(s):

Extracellular Vesicles ◽

Intestinal Mucosa ◽

Current Knowledge ◽

Cell Communication ◽

Bioactive Molecules ◽

Target Cells ◽

Immune Functions ◽

Intestinal Homeostasis ◽

General Terms ◽

Health And Disease

Communication between cells is crucial to preserve body homeostasis and health. Tightly controlled intercellular dialog is particularly relevant in the gut, where cells of the intestinal mucosa are constantly exposed to millions of microbes that have great impact on intestinal homeostasis by controlling barrier and immune functions. Recent knowledge involves extracellular vesicles (EVs) as mediators of such communication by transferring messenger bioactive molecules including proteins, lipids, and miRNAs between cells and tissues. The specific functions of EVs principally depend on the internal cargo, which upon delivery to target cells trigger signal events that modulate cellular functions. The vesicular cargo is greatly influenced by genetic, pathological, and environmental factors. This finding provides the basis for investigating potential clinical applications of EVs as therapeutic targets or diagnostic biomarkers. Here, we review current knowledge on the biogenesis and cargo composition of EVs in general terms. We then focus the attention to EVs released by cells of the intestinal mucosa and their impact on intestinal homeostasis in health and disease. We specifically highlight their role on epithelial barrier integrity, wound healing of epithelial cells, immunity, and microbiota shaping. Microbiota-derived EVs are not reviewed here.

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Are gap junctions necessary for cell-to-cell coupling of smooth muscle?: an update

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y92-063 ◽

1992 ◽

Vol 70 (4) ◽

pp. 481-490 ◽

Cited By ~ 22

Author(s):

R. E. Garfield ◽

G. Thilander ◽

M. G. Blennerhassett ◽

N. Sakai

Keyword(s):

Smooth Muscle ◽

Gap Junctions ◽

Current Knowledge ◽

Smooth Muscles ◽

Cell Communication ◽

Circular Muscle ◽

Cell Coupling ◽

And Function ◽

Longitudinal Layer ◽

Cell Cell

Earlier, it was questioned whether gap junctions (GJs) were necessary for cell–cell communication in smooth muscle, and GJs were not seen in some smooth muscles. We reexamined this question in the myometrium and in intestinal smooth muscle, in light of current knowledge of the presence and function of GJs. In the uterus, numerous studies show that an increase in GJ number is associated with the onset of delivery and is required for effective parturition. In all cases, this increase in GJ number and the changes in uterine contractility were correlated with increased electrical and metabolic coupling. Evidence for the much smaller, but detectable, degree of electrical coupling in the preterm uterus is explained by the small (but again detectable) number of GJs present. In the intestine, GJs are readily detected in the circular muscle layer but have not been described in the adjacent longitudinal layer. While our immunohistochemical studies failed to detect GJs in the longitudinal layer, this may not be adequate to prove their absence. Therefore, current knowledge of GJ number and function is adequate to explain cell–cell coupling in the uterus. Although it remains uncertain whether GJs are absent from the longitudinal muscle of the intestine, there is no definitive evidence that cell–cell coupling can occur by means other than GJs.Key words: gap junctions, myometrium, connexins, smooth muscle, cell communication.

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Extracellular Vesicles: An Emerging Nanoplatform for Cancer Therapy

Frontiers in Oncology ◽

10.3389/fonc.2020.606906 ◽

2021 ◽

Vol 10 ◽

Author(s):

Yifan Ma ◽

Shiyan Dong ◽

Xuefeng Li ◽

Betty Y. S. Kim ◽

Zhaogang Yang ◽

...

Keyword(s):

Cancer Therapy ◽

Extracellular Vesicles ◽

Drug Delivery Systems ◽

Current Knowledge ◽

Drug Loading ◽

Cell Communication ◽

Cancer Therapies ◽

Therapeutic Function ◽

Cancer Studies ◽

Potential Use

Extracellular vesicles (EVs) are cell-derived membrane particles that represent an endogenous mechanism for cell-to-cell communication. Since discovering that EVs have multiple advantages over currently available delivery platforms, such as their ability to overcome natural barriers, intrinsic cell targeting properties, and circulation stability, the potential use of EVs as therapeutic nanoplatforms for cancer studies has attracted considerable interest. To fully elucidate EVs’ therapeutic function for treating cancer, all current knowledge about cellular uptake and trafficking of EVs will be initially reviewed. In order to further improve EVs as anticancer therapeutics, engineering strategies for cancer therapy have been widely explored in the last decade, along with other cancer therapies. However, therapeutic applications of EVs as drug delivery systems have been limited because of immunological concerns, lack of methods to scale EV production, and efficient drug loading. We will review and discuss recent progress and remaining challenges in developing EVs as a delivery nanoplatform for cancer therapy.

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Mitophagy in Carcinogenesis and Tumor progression- A New paradigm with Emerging Importance

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621666210112121910 ◽

2021 ◽

Vol 21 ◽

Author(s):

Suman K. Ray ◽

Sukhes Mukherjee

Keyword(s):

Tumor Progression ◽

Cancer Cells ◽

Cancer Progression ◽

Mammalian Cells ◽

Mitochondrial Dynamics ◽

Clinical Importance ◽

Malignant Cells ◽

Malignant Growth ◽

New Paradigm ◽

Pancreatic Cancer Cells

: The term Mitophagy has been newly concerned in reforming metabolic landscape inside cancerous cells in addition to interface between malignant cells as well as other major constituents of tumor microenvironment. Several profoundly interrelated systems, comprising mitochondrial dynamics and mitophagy, function in mammalian cells as vital mitochondrial regulator process, and their consequence in neoplastic development has newly illuminated clinically. In specific instance of cancer cells, mitochondrialprotected metabolic paths are revamped to meet expanded bioenergetics along with biosynthetic necessities of malignant cells in addition to deal with oxidative stress. It is an exhausting task to foresee the role that mitophagy has on malignant growth cells since it relies upon various elements like cancer variability, malignant growth phase, genetic background and harmony between cell demand and accessibility. As per condition, mitophagy may have a double role as cancer suppressor for example Atg5 (autophagy related 5) or Atg7 (autophagy related 7) or execute promoter like function for instance FUNDC1 (FUN14 domain-containing protein 1), BNIP3 (BCL2/adenovirus E1B 19-kDa-interacting protein 3), PINK1 (PTEN-instigated kinase 1) etc. Tumor suppressive function of Parkin (E3 ubiquitin ligase) is likewise distinguished in mammary gland carcinoma where obstruction of mitophagy impacts tumor progression. In pancreatic cancer cells and in hepatocellular carcinoma hypermethylation of the BNIP3, promoter occurs that prevent HIF-1 (HypoxiaInducible Factor 1) binding besides ensuing initiation of mitophagy. Since the double role mitophagy has in malignant growth relying upon various circumstances and cell varieties, a range of studies have been going on mitophagy and its role in cancer progression and development is opening up a new paradigm with immense clinical importance.

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Lysosomal Exocytosis, Exosome Release and Secretory Autophagy: The Autophagic- and Endo-Lysosomal Systems Go Extracellular

International Journal of Molecular Sciences ◽

10.3390/ijms21072576 ◽

2020 ◽

Vol 21 (7) ◽

pp. 2576 ◽

Cited By ~ 15

Author(s):

Sandra Buratta ◽

Brunella Tancini ◽

Krizia Sagini ◽

Federica Delo ◽

Elisabetta Chiaradia ◽

...

Keyword(s):

Plasma Membrane ◽

Molecular Mechanisms ◽

Current Knowledge ◽

Cell Communication ◽

Lysosomal Storage ◽

Cellular Processes ◽

Age Related ◽

Extracellular Release ◽

A Cell ◽

Endosomal System

Beyond the consolidated role in degrading and recycling cellular waste, the autophagic- and endo-lysosomal systems play a crucial role in extracellular release pathways. Lysosomal exocytosis is a process leading to the secretion of lysosomal content upon lysosome fusion with plasma membrane and is an important mechanism of cellular clearance, necessary to maintain cell fitness. Exosomes are a class of extracellular vesicles originating from the inward budding of the membrane of late endosomes, which may not fuse with lysosomes but be released extracellularly upon exocytosis. In addition to garbage disposal tools, they are now considered a cell-to-cell communication mechanism. Autophagy is a cellular process leading to sequestration of cytosolic cargoes for their degradation within lysosomes. However, the autophagic machinery is also involved in unconventional protein secretion and autophagy-dependent secretion, which are fundamental mechanisms for toxic protein disposal, immune signalling and pathogen surveillance. These cellular processes underline the crosstalk between the autophagic and the endosomal system and indicate an intersection between degradative and secretory functions. Further, they suggest that the molecular mechanisms underlying fusion, either with lysosomes or plasma membrane, are key determinants to maintain cell homeostasis upon stressing stimuli. When they fail, the accumulation of undigested substrates leads to pathological consequences, as indicated by the involvement of autophagic and lysosomal alteration in human diseases, namely lysosomal storage disorders, age-related neurodegenerative diseases and cancer. In this paper, we reviewed the current knowledge on the functional role of extracellular release pathways involving lysosomes and the autophagic- and endo-lysosomal systems, evaluating their implication in health and disease.

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