1
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Bosch PS, Cho B, Axelrod JD. Flamingo participates in multiple models of cell competition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.24.559197. [PMID: 37790459 PMCID: PMC10542155 DOI: 10.1101/2023.09.24.559197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The growth and survival of cells with different fitness, such as those with a proliferative advantage or a deleterious mutation, is controlled through cell competition. During development, cell competition enables healthy cells to eliminate less fit cells that could jeopardize tissue integrity, and facilitates the elimination of pre-malignant cells by healthy cells as a surveillance mechanism to prevent oncogenesis. Malignant cells also benefit from cell competition to promote their expansion. Despite its ubiquitous presence, the mechanisms governing cell competition, particularly those common to developmental competition and tumorigenesis, are poorly understood. Here, we show that in Drosophila, the planar cell polarity (PCP) protein Flamingo (Fmi) is required by winners to maintain their status during cell competition in malignant tumors to overtake healthy tissue, in early pre-malignant cells when they overproliferate among wildtype cells, in healthy cells when they later eliminate pre-malignant cells, and by supercompetitors as they compete to occupy excessive territory within wildtype tissues. "Would-be" winners that lack Fmi are unable to over-proliferate, and instead become losers. We demonstrate that the role of Fmi in cell competition is independent of PCP, and that it uses a distinct mechanism that may more closely resemble one used in other less well-defined functions of Fmi.
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Affiliation(s)
- Pablo Sanchez Bosch
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., Stanford CA, 94305, USA
- These authors made equal contributions
| | - Bomsoo Cho
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., Stanford CA, 94305, USA
- These authors made equal contributions
| | - Jeffrey D Axelrod
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., Stanford CA, 94305, USA
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2
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Liu Y, Westerhoff HV. 'Social' versus 'asocial' cells-dynamic competition flux balance analysis. NPJ Syst Biol Appl 2023; 9:53. [PMID: 37898597 PMCID: PMC10613221 DOI: 10.1038/s41540-023-00313-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/09/2023] [Indexed: 10/30/2023] Open
Abstract
In multicellular organisms cells compete for resources or growth factors. If any one cell type wins, the co-existence of diverse cell types disappears. Existing dynamic Flux Balance Analysis (dFBA) does not accommodate changes in cell density caused by competition. Therefore we here develop 'dynamic competition Flux Balance Analysis' (dcFBA). With total biomass synthesis as objective, lower-growth-yield cells were outcompeted even when cells synthesized mutually required nutrients. Signal transduction between cells established co-existence, which suggests that such 'socialness' is required for multicellularity. Whilst mutants with increased specific growth rate did not outgrow the other cell types, loss of social characteristics did enable a mutant to outgrow the other cells. We discuss that 'asocialness' rather than enhanced growth rates, i.e., a reduced sensitivity to regulatory factors rather than enhanced growth rates, may characterize cancer cells and organisms causing ecological blooms. Therapies reinforcing cross-regulation may therefore be more effective than those targeting replication rates.
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Affiliation(s)
- Yanhua Liu
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Hans V Westerhoff
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
- Molecular Cell Biology, A-Life, Faculty of Science, Amsterdam Institute for Molecules, Medicines and Systems, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
- Stellenbosch Institute for Advanced Study (STIAS), Wallenberg Research Centre at Stellenbosch University, Stellenbosch, 7600, South Africa.
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3
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Sollazzo M, Paglia S, Di Giacomo S, Grifoni D. Apoptosis inhibition restrains primary malignant traits in different Drosophila cancer models. Front Cell Dev Biol 2023; 10:1043630. [PMID: 36704198 PMCID: PMC9871239 DOI: 10.3389/fcell.2022.1043630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023] Open
Abstract
Tumor cells exploit multiple mechanisms to evade apoptosis, hence the strategies aimed at reactivating cell death in cancer. However, recent studies are revealing that dying cells play remarkable pro-oncogenic roles. Among the mechanisms promoting cell death, cell competition, elicited by disparities in MYC activity in confronting cells, plays the primary role of assuring tissue robustness during development from Drosophila to mammals: cells with high MYC levels (winners) overproliferate while killing suboptimal neighbors (losers), whose death is essential to process completion. This mechanism is coopted by tumor cells in cancer initiation, where host cells succumb to high-MYC-expressing precancerous neighbors. Also in this case, inhibition of cell death restrains aberrant cell competition and rescues tissue structure. Inhibition of apoptosis may thus emerge as a good strategy to counteract cancer progression in competitive contexts; of note, we recently found a positive correlation between cell death amount at the tumor/stroma interface and MYC levels in human cancers. Here we used Drosophila to investigate the functional role of competition-dependent apoptosis in advanced cancers, observing dramatic changes in mass dimensions and composition following a boost in cell competition, rescued by apoptosis inhibition. This suggests the role of competition-dependent apoptosis be not confined to the early stages of tumorigenesis. We also show that apoptosis inhibition, beside restricting cancer mass, is sufficient to rescue tissue architecture and counteract cell migration in various cancer contexts, suggesting that a strong activation of the apoptotic pathways intensifies cancer burden by affecting distinct phenotypic traits at different stages of the disease.
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Affiliation(s)
- Manuela Sollazzo
- CanceЯEvolutionLab, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Simona Paglia
- CanceЯEvolutionLab, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Simone Di Giacomo
- CanceЯEvolutionLab, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Daniela Grifoni
- CanceЯEvolutionLab, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy,CanceЯEvolutionLab, Department of Life, Health and Environmental Sciences, University of L’Aquila, L’Aquila, Italy,*Correspondence: Daniela Grifoni,
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4
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Cell polarity and extrusion: How to polarize extrusion and extrude misspolarized cells? Curr Top Dev Biol 2023; 154:131-167. [PMID: 37100516 DOI: 10.1016/bs.ctdb.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The barrier function of epithelia is one of the cornerstones of the body plan organization of metazoans. It relies on the polarity of epithelial cells which organizes along the apico-basal axis the mechanical properties, signaling as well as transport. This barrier function is however constantly challenged by the fast turnover of epithelia occurring during morphogenesis or adult tissue homeostasis. Yet, the sealing property of the tissue can be maintained thanks to cell extrusion: a series of remodeling steps involving the dying cell and its neighbors leading to seamless cell expulsion. Alternatively, the tissue architecture can also be challenged by local damages or the emergence of mutant cells that may alter its organization. This includes mutants of the polarity complexes which can generate neoplastic overgrowths or be eliminated by cell competition when surrounded by wild type cells. In this review, we will provide an overview of the regulation of cell extrusion in various tissues focusing on the relationship between cell polarity, cell organization and the direction of cell expulsion. We will then describe how local perturbations of polarity can also trigger cell elimination either by apoptosis or by cell exclusion, focusing specifically on how polarity defects can be directly causal to cell elimination. Overall, we propose a general framework connecting the influence of polarity on cell extrusion and its contribution to aberrant cell elimination.
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5
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Kumar A, Baker NE. The CRL4 E3 ligase Mahjong/DCAF1 controls cell competition through the transcription factor Xrp1, independently of polarity genes. Development 2022; 149:dev200795. [PMID: 36278853 PMCID: PMC9845748 DOI: 10.1242/dev.200795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 10/10/2022] [Indexed: 11/17/2022]
Abstract
Cell competition, the elimination of cells surrounded by more fit neighbors, is proposed to suppress tumorigenesis. Mahjong (Mahj), a ubiquitin E3 ligase substrate receptor, has been thought to mediate competition of cells mutated for lethal giant larvae (lgl), a neoplastic tumor suppressor that defines apical-basal polarity of epithelial cells. Here, we show that Drosophila cells mutated for mahjong, but not for lgl [l(2)gl], are competed because they express the bZip-domain transcription factor Xrp1, already known to eliminate cells heterozygous for ribosomal protein gene mutations (Rp/+ cells). Xrp1 expression in mahj mutant cells results in activation of JNK signaling, autophagosome accumulation, eIF2α phosphorylation and lower translation, just as in Rp/+ cells. Cells mutated for damage DNA binding-protein 1 (ddb1; pic) or cullin 4 (cul4), which encode E3 ligase partners of Mahj, also display Xrp1-dependent phenotypes, as does knockdown of proteasome subunits. Our data suggest a new model of mahj-mediated cell competition that is independent of apical-basal polarity and couples Xrp1 to protein turnover.
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Affiliation(s)
- Amit Kumar
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Nicholas E. Baker
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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6
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A role for Flower and cell death in controlling morphogen gradient scaling. Nat Cell Biol 2022; 24:424-433. [PMID: 35301437 DOI: 10.1038/s41556-022-00858-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 01/28/2022] [Indexed: 11/08/2022]
Abstract
During development, morphogen gradients encode positional information to pattern morphological structures during organogenesis1. Some gradients, like that of Dpp in the fly wing, remain proportional to the size of growing organs-that is, they scale. Gradient scaling keeps morphological patterns proportioned in organs of different sizes2,3. Here we show a mechanism of scaling that ensures that, when the gradient is smaller than the organ, cell death trims the developing tissue to match the size of the gradient. Scaling is controlled by molecular associations between Dally and Pentagone, known factors involved in scaling, and a key factor that mediates cell death, Flower4-6. We show that Flower activity in gradient expansion is not dominated by cell death, but by the activity of Dally/Pentagone on scaling. Here we show a potential connection between scaling and cell death that may uncover a molecular toolbox hijacked by tumours.
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7
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La Marca JE, Willoughby LF, Allan K, Portela M, Goh PK, Tiganis T, Richardson HE. PTP61F Mediates Cell Competition and Mitigates Tumorigenesis. Int J Mol Sci 2021; 22:12732. [PMID: 34884538 PMCID: PMC8657627 DOI: 10.3390/ijms222312732] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/23/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
Tissue homeostasis via the elimination of aberrant cells is fundamental for organism survival. Cell competition is a key homeostatic mechanism, contributing to the recognition and elimination of aberrant cells, preventing their malignant progression and the development of tumors. Here, using Drosophila as a model organism, we have defined a role for protein tyrosine phosphatase 61F (PTP61F) (orthologue of mammalian PTP1B and TCPTP) in the initiation and progression of epithelial cancers. We demonstrate that a Ptp61F null mutation confers cells with a competitive advantage relative to neighbouring wild-type cells, while elevating PTP61F levels has the opposite effect. Furthermore, we show that knockdown of Ptp61F affects the survival of clones with impaired cell polarity, and that this occurs through regulation of the JAK-STAT signalling pathway. Importantly, PTP61F plays a robust non-cell-autonomous role in influencing the elimination of adjacent polarity-impaired mutant cells. Moreover, in a neoplastic RAS-driven polarity-impaired tumor model, we show that PTP61F levels determine the aggressiveness of tumors, with Ptp61F knockdown or overexpression, respectively, increasing or reducing tumor size. These effects correlate with the regulation of the RAS-MAPK and JAK-STAT signalling by PTP61F. Thus, PTP61F acts as a tumor suppressor that can function in an autonomous and non-cell-autonomous manner to ensure cellular fitness and attenuate tumorigenesis.
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Affiliation(s)
- John E. La Marca
- Cell Polarity, Cell Signaling & Cancer Laboratory, Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia; (J.E.L.M.); (K.A.); (M.P.)
| | - Lee F. Willoughby
- Cell Cycle & Development Laboratory, Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3002, Australia;
| | - Kirsten Allan
- Cell Polarity, Cell Signaling & Cancer Laboratory, Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia; (J.E.L.M.); (K.A.); (M.P.)
| | - Marta Portela
- Cell Polarity, Cell Signaling & Cancer Laboratory, Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia; (J.E.L.M.); (K.A.); (M.P.)
| | - Pei Kee Goh
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; (P.K.G.); (T.T.)
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Tony Tiganis
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; (P.K.G.); (T.T.)
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Helena E. Richardson
- Cell Polarity, Cell Signaling & Cancer Laboratory, Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia; (J.E.L.M.); (K.A.); (M.P.)
- Cell Cycle & Development Laboratory, Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3002, Australia;
- Peter MacCallum Department of Oncology, Department of Anatomy & Neuroscience, Department of Biochemistry, University of Melbourne, Melbourne, VIC 3010, Australia
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8
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A Blueprint for Cancer-Related Inflammation and Host Innate Immunity. Cells 2021; 10:cells10113211. [PMID: 34831432 PMCID: PMC8623541 DOI: 10.3390/cells10113211] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/27/2021] [Accepted: 11/10/2021] [Indexed: 12/30/2022] Open
Abstract
Both in situ and allograft models of cancer in juvenile and adult Drosophila melanogaster fruit flies offer a powerful means for unravelling cancer gene networks and cancer-host interactions. They can also be used as tools for cost-effective drug discovery and repurposing. Moreover, in situ modeling of emerging tumors makes it possible to address cancer initiating events-a black box in cancer research, tackle the innate antitumor immune responses to incipient preneoplastic cells and recurrent growing tumors, and decipher the initiation and evolution of inflammation. These studies in Drosophila melanogaster can serve as a blueprint for studies in more complex organisms and help in the design of mechanism-based therapies for the individualized treatment of cancer diseases in humans. This review focuses on new discoveries in Drosophila related to the diverse innate immune responses to cancer-related inflammation and the systemic effects that are so detrimental to the host.
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9
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Costa-Rodrigues C, Couceiro J, Moreno E. Cell competition from development to neurodegeneration. Dis Model Mech 2021; 14:269331. [PMID: 34190316 PMCID: PMC8277968 DOI: 10.1242/dmm.048926] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Cell competition is a process by which suboptimal cells are eliminated to the benefit of cells with higher fitness. It is a surveillance mechanism that senses differences in the fitness status by several modes, such as expression of fitness fingerprints, survival factor uptake rate and resistance to mechanical stress. Fitness fingerprints-mediated cell competition recognizes isoforms of the transmembrane protein Flower, and translates the relative fitness of cells into distinct fates through the Flower code. Impairments in cell competition potentiate the development of diseases like cancer and ageing-related pathologies. In cancer, malignant cells acquire a supercompetitor behaviour, killing the neighbouring cells and overtaking the tissue, thus avoiding elimination. Neurodegenerative disorders affect millions of people and are characterized by cognitive decline and locomotor deficits. Alzheimer's disease is the most common form of dementia, and one of the largely studied diseases. However, the cellular processes taking place remain unclear. Drosophila melanogaster is an emerging neurodegeneration model due to its versatility as a tool for genetic studies. Research in a Drosophila Alzheimer's disease model detected fitness markers in the suboptimal and hyperactive neurons, thus establishing a link between cell competition and Alzheimer's disease. In this Review, we overview cell competition and the new insights related to neurodegenerative disorders, and discuss how research in the field might contribute to the development of new therapeutic targets for these diseases.
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Affiliation(s)
| | - Joana Couceiro
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
| | - Eduardo Moreno
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
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10
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Ma X. Context-dependent interplay between Hippo and JNK pathway in Drosophila. AIMS GENETICS 2021. [DOI: 10.3934/genet.2014.1.20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
AbstractBoth Hippo and JNK signaling have well-established roles in regulating many physiological processes, including cell proliferation, growth, survival, and migration. An increasing body of evidence shows that dysregulation of either Hippo or JNK pathway would lead to tumorigenesis. Recently, studies in Drosophila has coupled Hippo with JNK pathway in numerous ways ranging from tissue regeneration to growth control. In this review, I provide an overview of the current understanding of crosstalk between Hippo and JNK pathway in Drosophila, and discuss their context-dependent interactions in gut homeostasis, regeneration, cell competition and migration.
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Affiliation(s)
- Xianjue Ma
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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11
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Destefanis F, Manara V, Bellosta P. Myc as a Regulator of Ribosome Biogenesis and Cell Competition: A Link to Cancer. Int J Mol Sci 2020; 21:ijms21114037. [PMID: 32516899 PMCID: PMC7312820 DOI: 10.3390/ijms21114037] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 12/14/2022] Open
Abstract
The biogenesis of ribosomes is a finely regulated multistep process linked to cell proliferation and growth-processes which require a high rate of protein synthesis. One of the master regulators of ribosome biogenesis is Myc, a well-known proto-oncogene that has an important role in ribosomal function and in the regulation of protein synthesis. The relationship between Myc and the ribosomes was first highlighted in Drosophila, where Myc's role in controlling Pol-I, II and III was evidenced by both microarrays data, and by the ability of Myc to control growth (mass), and cellular and animal size. Moreover, Myc can induce cell competition, a physiological mechanism through which cells with greater fitness grow better and thereby prevail over less competitive cells, which are actively eliminated by apoptosis. Myc-induced cell competition was shown to regulate both vertebrate development and tumor promotion; however, how these functions are linked to Myc's control of ribosome biogenesis, protein synthesis and growth is not clear yet. In this review, we will discuss the major pathways that link Myc to ribosomal biogenesis, also in light of its function in cell competition, and how these mechanisms may reflect its role in favoring tumor promotion.
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Affiliation(s)
- Francesca Destefanis
- Department of Cellular, Computational and Integrative Biology (CiBio), University of Trento, 38123 Trento, Italy; (F.D.); (V.M.)
| | - Valeria Manara
- Department of Cellular, Computational and Integrative Biology (CiBio), University of Trento, 38123 Trento, Italy; (F.D.); (V.M.)
| | - Paola Bellosta
- Department of Cellular, Computational and Integrative Biology (CiBio), University of Trento, 38123 Trento, Italy; (F.D.); (V.M.)
- Department of Medicine, NYU Langone Medical Center, New York, NY 10016, USA
- Correspondence: ; Tel.: +39-0461-283070
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12
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La Marca JE, Richardson HE. Two-Faced: Roles of JNK Signalling During Tumourigenesis in the Drosophila Model. Front Cell Dev Biol 2020; 8:42. [PMID: 32117973 PMCID: PMC7012784 DOI: 10.3389/fcell.2020.00042] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/17/2020] [Indexed: 12/27/2022] Open
Abstract
The highly conserved c-Jun N-terminal Kinase (JNK) signalling pathway has many functions, regulating a diversity of processes: from cell movement during embryogenesis to the stress response of cells after environmental insults. Studies modelling cancer using the vinegar fly, Drosophila melanogaster, have identified both pro- and anti-tumourigenic roles for JNK signalling, depending on context. As a tumour suppressor, JNK signalling commonly is activated by conserved Tumour Necrosis Factor (TNF) signalling, which promotes the caspase-mediated death of tumourigenic cells. JNK pathway activation can also occur via actin cytoskeleton alterations, and after cellular damage inflicted by reactive oxygen species (ROS). Additionally, JNK signalling frequently acts in concert with Salvador-Warts-Hippo (SWH) signalling – either upstream of or parallel to this potent growth-suppressing pathway. As a tumour promoter, JNK signalling is co-opted by cells expressing activated Ras-MAPK signalling (among other pathways), and used to drive cell morphological changes, induce invasive behaviours, block differentiation, and enable persistent cell proliferation. Furthermore, JNK is capable of non-autonomous influences within tumour microenvironments by effecting the transcription of various cell growth- and proliferation-promoting molecules. In this review, we discuss these aspects of JNK signalling in Drosophila tumourigenesis models, and highlight recent publications that have expanded our knowledge of this important and versatile pathway.
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Affiliation(s)
- John E La Marca
- Richardson Laboratory, Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Helena E Richardson
- Richardson Laboratory, Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
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13
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Bajpai A, Sinha P. Hh signaling from de novo organizers drive lgl neoplasia in Drosophila epithelium. Dev Biol 2020; 457:1-8. [PMID: 31557471 PMCID: PMC7116463 DOI: 10.1016/j.ydbio.2019.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 08/22/2019] [Accepted: 09/20/2019] [Indexed: 01/20/2023]
Abstract
The Hedgehog (Hh) morphogen regulates growth and patterning. Since Hh signaling is also implicated in carcinogenesis, it is conceivable that de novo Hh-secreting organizers, if formed in association with oncogenic hit could be tumor-cooperative. Here we validate this hypothesis using the Drosophila model of cooperative epithelial carcinogenesis. We generate somatic clones with simultaneous loss of tumor suppressor, Lgl, and gain of the posterior compartment selector, Engrailed (En), known to induce synthesis of Hh. We show that lgl UAS-en clones in the anterior wing compartment trigger Hh signaling cascade via cross-talk with their Ci-expressing wild type cell neighbors. Hh-Dpp signaling from clone boundaries of such ectopically formed de novo organizers in turn drive lgl carcinogenesis. By contrast, Ci-expressing lgl clones transform by autocrine and/or juxtracine activation of Hh signaling in only the posterior compartment. We further show that sequestration of the Hh ligand or loss of Dpp receptor, Tkv, in these Hh-sending or -receiving lgl clones arrested their carcinogenesis. Our results therefore reveal a hitherto unrecognized mechanism of tumor cooperation by developmental organizers, which are induced fortuitously by oncogenic hits.
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Affiliation(s)
- Anjali Bajpai
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208 016, India.
| | - Pradip Sinha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208 016, India.
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14
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The Initial Stage of Tumorigenesis in Drosophila Epithelial Tissues. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019. [PMID: 31520350 DOI: 10.1007/978-3-030-23629-8_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Cancer development originates in a single mutant cell transformed from a normal cell, including further evolution of pro-tumor cells through additional mutations into malignant cancer tissues. Data from recent studies, however, suggest that most pro-tumor cells do not develop into tumors but remain dormant within or are prophylactically eliminated from tissues unless bestowed with additional driver mutations. Drosophila melanogaster has provided very efficient model systems, such as imaginal discs and ovarian follicular epithelia, to study the initial stage of tumorigenesis. This review will focus on the behaviors of emerging pro-tumor cells surrounded by normal cells and situations where they initiate tumor development.
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15
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Bowling S, Lawlor K, Rodríguez TA. Cell competition: the winners and losers of fitness selection. Development 2019; 146:146/13/dev167486. [PMID: 31278123 DOI: 10.1242/dev.167486] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The process of cell competition results in the 'elimination of cells that are viable but less fit than surrounding cells'. Given the highly heterogeneous nature of our tissues, it seems increasingly likely that cells are engaged in a 'survival of the fittest' battle throughout life. The process has a myriad of positive roles in the organism: it selects against mutant cells in developing tissues, prevents the propagation of oncogenic cells and eliminates damaged cells during ageing. However, 'super-fit' cancer cells can exploit cell competition mechanisms to expand and spread. Here, we review the regulation, roles and risks of cell competition in organism development, ageing and disease.
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Affiliation(s)
- Sarah Bowling
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Katerina Lawlor
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Tristan A Rodríguez
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
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16
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La Marca JE, Diepstraten ST, Hodge AL, Wang H, Hart AH, Richardson HE, Somers WG. Strip and Cka negatively regulate JNK signalling during Drosophila spermatogenesis. Development 2019; 146:dev.174292. [PMID: 31164352 DOI: 10.1242/dev.174292] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 05/24/2019] [Indexed: 12/16/2022]
Abstract
One fundamental property of a stem cell niche is the exchange of molecular signals between its component cells. Niche models, such as the Drosophila melanogaster testis, have been instrumental in identifying and studying the conserved genetic factors that contribute to niche molecular signalling. Here, we identify jam packed (jam), an allele of Striatin interacting protein (Strip), which is a core member of the highly conserved Striatin-interacting phosphatase and kinase (STRIPAK) complex. In the developing Drosophila testis, Strip cell-autonomously regulates the differentiation and morphology of the somatic lineage, and non-cell-autonomously regulates the proliferation and differentiation of the germline lineage. Mechanistically, Strip acts in the somatic lineage with its STRIPAK partner, Connector of kinase to AP-1 (Cka), where they negatively regulate the Jun N-terminal kinase (JNK) signalling pathway. Our study reveals a novel role for Strip/Cka in JNK pathway regulation during spermatogenesis within the developing Drosophila testis.
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Affiliation(s)
- John E La Marca
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
| | - Sarah T Diepstraten
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
| | - Amy L Hodge
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
| | - Hongyan Wang
- Neuroscience and Behavioral Disorders Program, Duke-National University of Singapore Graduate Medical School, Singapore 169857.,National University of Singapore Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
| | - Adam H Hart
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
| | - Helena E Richardson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
| | - W Gregory Somers
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia 3086
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17
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Transcriptional versus metabolic control of cell fitness during cell competition. Semin Cancer Biol 2019; 63:36-43. [PMID: 31102668 PMCID: PMC7221347 DOI: 10.1016/j.semcancer.2019.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 02/07/2023]
Abstract
The maintenance of tissue homeostasis and health relies on the efficient removal of damaged or otherwise suboptimal cells. One way this is achieved is through cell competition, a fitness quality control mechanism that eliminates cells that are less fit than their neighbours. Through this process, cell competition has been shown to play diverse roles in development and in the adult, including in homeostasis and tumour suppression. However, over the last few years it has also become apparent that certain oncogenic mutations can provide cells with a competitive advantage that promotes their expansion via the elimination of surrounding wild-type cells. Thus, understanding how this process is initiated and regulated will provide important insights with relevance to a number of different research areas. A key question in cell competition is what determines the competitive fitness of a cell. Here, we will review what is known about this question by focussing on two non-mutually exclusive possibilities; first, that the activity of a subset of transcription factors determines competitive fitness, and second, that the outcome of cell competition is determined by the relative cellular metabolic status.
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18
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Paglia S, Sollazzo M, Di Giacomo S, Strocchi S, Grifoni D. Exploring MYC relevance to cancer biology from the perspective of cell competition. Semin Cancer Biol 2019; 63:49-59. [PMID: 31102666 DOI: 10.1016/j.semcancer.2019.05.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 12/13/2022]
Abstract
Cancer has long been regarded and treated as a foreign body appearing by mistake inside a living organism. However, now we know that cancer cells communicate with neighbours, thereby creating modified environments able to support their unusual need for nutrients and space. Understanding the molecular basis of these bi-directional interactions is thus mandatory to approach the complex nature of cancer. Since their discovery, MYC proteins have been showing to regulate a steadily increasing number of processes impacting cell fitness, and are consistently found upregulated in almost all human tumours. Of interest, MYC takes part in cell competition, an evolutionarily conserved fitness comparison strategy aimed at detecting weakened cells, which are then committed to death, removed from the tissue and replaced by fitter neighbours. During physiological development, MYC-mediated cell competition is engaged to eliminate cells with suboptimal MYC levels, so as to guarantee selective growth of the fittest and proper homeostasis, while transformed cells expressing high levels of MYC coopt cell competition to subvert tissue constraints, ultimately disrupting homeostasis. Therefore, the interplay between cells with different MYC levels may result in opposite functional outcomes, depending on the nature of the players. In the present review, we describe the most recent findings on the role of MYC-mediated cell competition in different contexts, with a special emphasis on its impact on cancer initiation and progression. We also discuss the relevance of competition-associated cell death to cancer disease.
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Affiliation(s)
- Simona Paglia
- CanceЯEvolutionLab, University of Bologna, Department of Pharmacy and Biotechnology, Via Selmi 3, 40126, Bologna, Italy.
| | - Manuela Sollazzo
- CanceЯEvolutionLab, University of Bologna, Department of Pharmacy and Biotechnology, Via Selmi 3, 40126, Bologna, Italy.
| | - Simone Di Giacomo
- CanceЯEvolutionLab, University of Bologna, Department of Pharmacy and Biotechnology, Via Selmi 3, 40126, Bologna, Italy.
| | - Silvia Strocchi
- CanceЯEvolutionLab, University of Bologna, Department of Pharmacy and Biotechnology, Via Selmi 3, 40126, Bologna, Italy.
| | - Daniela Grifoni
- CanceЯEvolutionLab, University of Bologna, Department of Pharmacy and Biotechnology, Via Selmi 3, 40126, Bologna, Italy.
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19
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Mirzoyan Z, Sollazzo M, Allocca M, Valenza AM, Grifoni D, Bellosta P. Drosophila melanogaster: A Model Organism to Study Cancer. Front Genet 2019; 10:51. [PMID: 30881374 PMCID: PMC6405444 DOI: 10.3389/fgene.2019.00051] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 01/21/2019] [Indexed: 12/26/2022] Open
Abstract
Cancer is a multistep disease driven by the activation of specific oncogenic pathways concomitantly with the loss of function of tumor suppressor genes that act as sentinels to control physiological growth. The conservation of most of these signaling pathways in Drosophila, and the ability to easily manipulate them genetically, has made the fruit fly a useful model organism to study cancer biology. In this review we outline the basic mechanisms and signaling pathways conserved between humans and flies responsible of inducing uncontrolled growth and cancer development. Second, we describe classic and novel Drosophila models used to study different cancers, with the objective to discuss their strengths and limitations on their use to identify signals driving growth cell autonomously and within organs, drug discovery and for therapeutic approaches.
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Affiliation(s)
- Zhasmine Mirzoyan
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Manuela Sollazzo
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Mariateresa Allocca
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | | | - Daniela Grifoni
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Paola Bellosta
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy.,Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.,Department of Biosciences, University of Milan, Milan, Italy.,Department of Medicine, NYU Langone Medical Center, New York, NY, United States
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20
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Fahey-Lozano N, La Marca JE, Portela M, Richardson HE. Drosophila Models of Cell Polarity and Cell Competition in Tumourigenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1167:37-64. [PMID: 31520348 DOI: 10.1007/978-3-030-23629-8_3] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cell competition is an important surveillance mechanism that measures relative fitness between cells in a tissue during development, homeostasis, and disease. Specifically, cells that are "less fit" (losers) are actively eliminated by relatively "more fit" (winners) neighbours, despite the less fit cells otherwise being able to survive in a genetically uniform tissue. Originally described in the epithelial tissues of Drosophila larval imaginal discs, cell competition has since been shown to occur in other epithelial and non-epithelial Drosophila tissues, as well as in mammalian model systems. Many genes and signalling pathways have been identified as playing conserved roles in the mechanisms of cell competition. Among them are genes required for the establishment and maintenance of apico-basal cell polarity: the Crumbs/Stardust/Patj (Crb/Sdt/Patj), Bazooka/Par-6/atypical Protein Kinase C (Baz/Par-6/aPKC), and Scribbled/Discs large 1/Lethal (2) giant larvae (Scrib/Dlg1/L(2)gl) modules. In this chapter, we describe the concepts and mechanisms of cell competition, with emphasis on the relationship between cell polarity proteins and cell competition, particularly the Scrib/Dlg1/L(2)gl module, since this is the best described module in this emerging field.
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Affiliation(s)
- Natasha Fahey-Lozano
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - John E La Marca
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Marta Portela
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - Helena E Richardson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia.
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21
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Madan E, Gogna R, Moreno E. Cell competition in development: information from flies and vertebrates. Curr Opin Cell Biol 2018; 55:150-157. [DOI: 10.1016/j.ceb.2018.08.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/03/2018] [Accepted: 08/03/2018] [Indexed: 12/20/2022]
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22
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A genetic mosaic screen identifies genes modulating Notch signaling in Drosophila. PLoS One 2018; 13:e0203781. [PMID: 30235233 PMCID: PMC6147428 DOI: 10.1371/journal.pone.0203781] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 08/27/2018] [Indexed: 01/08/2023] Open
Abstract
Notch signaling is conserved in most multicellular organisms and plays critical roles during animal development. The core components and major signal transduction mechanism of Notch signaling have been extensively studied. However, our understanding of how Notch signaling activity is regulated in diverse developmental processes still remains incomplete. Here, we report a genetic mosaic screen in Drosophila melanogaster that leads to identification of Notch signali ng modulators during wing development. We discovered a group of genes required for the formation of the fly wing margin, a developmental process that is strictly dependent on the balanced Notch signaling activity. These genes encode transcription factors, protein phosphatases, vacuolar ATPases and factors required for RNA transport, stability, and translation. Our data support the view that Notch signaling is controlled through a wide range of molecular processes. These results also provide foundations for further study by showing that Me31B and Wdr62 function as two novel modulators of Notch signaling activity.
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23
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Portela M, Yang L, Paul S, Li X, Veraksa A, Parsons LM, Richardson HE. Lgl reduces endosomal vesicle acidification and Notch signaling by promoting the interaction between Vap33 and the V-ATPase complex. Sci Signal 2018; 11:11/533/eaar1976. [PMID: 29871910 DOI: 10.1126/scisignal.aar1976] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epithelial cell polarity is linked to the control of tissue growth and tumorigenesis. The tumor suppressor and cell polarity protein lethal-2-giant larvae (Lgl) promotes Hippo signaling and inhibits Notch signaling to restrict tissue growth in Drosophila melanogaster Notch signaling is greater in lgl mutant tissue than in wild-type tissue because of increased acidification of endosomal vesicles, which promotes the proteolytic processing and activation of Notch by γ-secretase. We showed that the increased Notch signaling and tissue growth defects of lgl mutant tissue depended on endosomal vesicle acidification mediated by the vacuolar adenosine triphosphatase (V-ATPase). Lgl promoted the activity of the V-ATPase by interacting with Vap33 (VAMP-associated protein of 33 kDa). Vap33 physically and genetically interacted with Lgl and V-ATPase subunits and repressed V-ATPase-mediated endosomal vesicle acidification and Notch signaling. Vap33 overexpression reduced the abundance of the V-ATPase component Vha44, whereas Lgl knockdown reduced the binding of Vap33 to the V-ATPase component Vha68-3. Our data indicate that Lgl promotes the binding of Vap33 to the V-ATPase, thus inhibiting V-ATPase-mediated endosomal vesicle acidification and thereby reducing γ-secretase activity, Notch signaling, and tissue growth. Our findings implicate the deregulation of Vap33 and V-ATPase activity in polarity-impaired epithelial cancers.
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Affiliation(s)
- Marta Portela
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia.,Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Avenida Doctor Arce, 37, Madrid 28002, Spain
| | - Liu Yang
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Sayantanee Paul
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Xia Li
- Department of Mathematics and Statistics, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Alexey Veraksa
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Linda M Parsons
- Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Helena E Richardson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia. .,Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Sir Peter MacCallum Department of Oncology, Department of Anatomy and Neuroscience, Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Victoria 3010, Australia
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24
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Paul MS, Singh A, Dutta D, Mutsuddi M, Mukherjee A. Notch signals modulate lgl mediated tumorigenesis by the activation of JNK signaling. BMC Res Notes 2018; 11:247. [PMID: 29661224 PMCID: PMC5902968 DOI: 10.1186/s13104-018-3350-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/06/2018] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES Oncogenic potential of Notch signaling and its cooperation with other factors to affect proliferation are widely established. Notch exhibits a cooperative effect with loss of a cell polarity gene, scribble to induce neoplastic overgrowth. Oncogenic Ras also show cooperative effect with loss of cell polarity genes such as scribble (scrib), lethal giant larvae (lgl) and discs large to induce neoplastic overgrowth and invasion. Our study aims at assessing the cooperation of activated Notch with loss of function of lgl in tumor overgrowth, and the mode of JNK signaling activation in this context. RESULTS In the present study, we use Drosophila as an in vivo model to show the synergy between activated Notch (N act ) and loss of function of lgl (lgl-IR) in tumor progression. Coexpression of N act and lgl-IR results in massive tumor overgrowth and displays hallmarks of cancer, such as MMP1 upregulation and loss of epithelial integrity. We further show activation of JNK signaling and upregulation of its receptor, Grindelwald in N act /lgl-IR tumor. In contrast to previously described Notch act /scrib-/- tumor, our experiments in N act /lgl-IR tumor showed the presence of dying cells along with tumorous overgrowth.
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Affiliation(s)
- Maimuna Sali Paul
- Department of Molecular and Human Genetics, Banaras Hindu University, Varanasi, 221 005, India
| | - Ankita Singh
- Department of Molecular and Human Genetics, Banaras Hindu University, Varanasi, 221 005, India
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Banaras Hindu University, Varanasi, 221 005, India
| | - Mousumi Mutsuddi
- Department of Molecular and Human Genetics, Banaras Hindu University, Varanasi, 221 005, India.
| | - Ashim Mukherjee
- Department of Molecular and Human Genetics, Banaras Hindu University, Varanasi, 221 005, India.
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25
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Saito Y, Desai RR, Muthuswamy SK. Reinterpreting polarity and cancer: The changing landscape from tumor suppression to tumor promotion. Biochim Biophys Acta Rev Cancer 2018; 1869:103-116. [DOI: 10.1016/j.bbcan.2017.12.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/21/2022]
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26
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Parvy JP, Hodgson JA, Cordero JB. Drosophila as a Model System to Study Nonautonomous Mechanisms Affecting Tumour Growth and Cell Death. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7152962. [PMID: 29725601 PMCID: PMC5872677 DOI: 10.1155/2018/7152962] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 02/04/2018] [Indexed: 12/26/2022]
Abstract
The study of cancer has represented a central focus in medical research for over a century. The great complexity and constant evolution of the pathology require the use of multiple research model systems and interdisciplinary approaches. This is necessary in order to achieve a comprehensive understanding into the mechanisms driving disease initiation and progression, to aid the development of appropriate therapies. In recent decades, the fruit fly Drosophila melanogaster and its associated powerful genetic tools have become a very attractive model system to study tumour-intrinsic and non-tumour-derived processes that mediate tumour development in vivo. In this review, we will summarize recent work on Drosophila as a model system to study cancer biology. We will focus on the interactions between tumours and their microenvironment, including extrinsic mechanisms affecting tumour growth and how tumours impact systemic host physiology.
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Affiliation(s)
- Jean-Philippe Parvy
- CRUK Beatson Institute, Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Joseph A. Hodgson
- CRUK Beatson Institute, Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Julia B. Cordero
- CRUK Beatson Institute, Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow G61 1QH, UK
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27
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Modelling Cooperative Tumorigenesis in Drosophila. BIOMED RESEARCH INTERNATIONAL 2018; 2018:4258387. [PMID: 29693007 PMCID: PMC5859872 DOI: 10.1155/2018/4258387] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 01/21/2018] [Indexed: 12/13/2022]
Abstract
The development of human metastatic cancer is a multistep process, involving the acquisition of several genetic mutations, tumour heterogeneity, and interactions with the surrounding microenvironment. Due to the complexity of cancer development in mammals, simpler model organisms, such as the vinegar fly, Drosophila melanogaster, are being utilized to provide novel insights into the molecular mechanisms involved. In this review, we highlight recent advances in modelling tumorigenesis using the Drosophila model, focusing on the cooperation of oncogenes or tumour suppressors, and the interaction of mutant cells with the surrounding tissue in epithelial tumour initiation and progression.
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28
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Stephens R, Lim K, Portela M, Kvansakul M, Humbert PO, Richardson HE. The Scribble Cell Polarity Module in the Regulation of Cell Signaling in Tissue Development and Tumorigenesis. J Mol Biol 2018; 430:3585-3612. [PMID: 29409995 DOI: 10.1016/j.jmb.2018.01.011] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/19/2018] [Accepted: 01/19/2018] [Indexed: 01/22/2023]
Abstract
The Scribble cell polarity module, comprising Scribbled (Scrib), Discs-large (Dlg) and Lethal-2-giant larvae (Lgl), has a tumor suppressive role in mammalian epithelial cancers. The Scribble module proteins play key functions in the establishment and maintenance of different modes of cell polarity, as well as in the control of tissue growth, differentiation and directed cell migration, and therefore are major regulators of tissue development and homeostasis. Whilst molecular details are known regarding the roles of Scribble module proteins in cell polarity regulation, their precise mode of action in the regulation of other key cellular processes remains enigmatic. An accumulating body of evidence indicates that Scribble module proteins play scaffolding roles in the control of various signaling pathways, which are linked to the control of tissue growth, differentiation and cell migration. Multiple Scrib, Dlg and Lgl interacting proteins have been discovered, which are involved in diverse processes, however many function in the regulation of cellular signaling. Herein, we review the components of the Scrib, Dlg and Lgl protein interactomes, and focus on the mechanism by which they regulate cellular signaling pathways in metazoans, and how their disruption leads to cancer.
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Affiliation(s)
- Rebecca Stephens
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Krystle Lim
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Marta Portela
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute (CSIC), Avenida Doctor Arce, 37, Madrid 28002, Spain
| | - Marc Kvansakul
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Patrick O Humbert
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria, Australia; Department of Biochemistry & Molecular Biology, University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Helena E Richardson
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria, Australia; Department of Biochemistry & Molecular Biology, University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Anatomy & Neurobiology, University of Melbourne, Melbourne, Victoria 3010, Australia.
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29
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Troponin-I enhances and is required for oncogenic overgrowth. Oncotarget 2018; 7:52631-52642. [PMID: 27437768 PMCID: PMC5288137 DOI: 10.18632/oncotarget.10616] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 07/02/2016] [Indexed: 12/31/2022] Open
Abstract
Human tumors of various tissue origins show an intriguing over-expression of genes not considered oncogenes, such as that encoding Troponin-I (TnI), a well-known muscle protein. Out of the three TnI genes known in humans, the slow form, TNNI1, is affected the most. Drosophila has only one TnI gene, wupA. Here, we studied excess- and loss-of function of wupA in Drosophila, and assayed TNNI1 down regulation in human tumors growing in mice. Drosophila TnI excess-of-function increases proliferation and potentiates oncogenic mutations in Ras, Notch and Lgl genes. By contrast, TnI loss-of-function reduces proliferation and antagonizes the overgrowth due to these oncogenic mutations. Troponin-I defective cells undergo Flower- and Sparc-dependent cell competition. TnI can localize to the nucleus and its excess elicits transcriptional up-regulation of InR, Rap1 and Dilp8, which is consistent with the increased cell proliferation. Human tumor cell lines treated with a human Troponin-I peptide arrest in G0/G1. In addition, proliferation of non-small-cell lung carcinoma xenografts in mice is restrained by TNNI1 down-regulation. Thus, Troponin-I reveals a novel function in cell proliferation that may be of therapeutic interest in certain types of cancer.
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30
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Daniel SG, Russ AD, Guthridge KM, Raina AI, Estes PS, Parsons LM, Richardson HE, Schroeder JA, Zarnescu DC. miR-9a mediates the role of Lethal giant larvae as an epithelial growth inhibitor in Drosophila. Biol Open 2018; 7:bio.027391. [PMID: 29361610 PMCID: PMC5829493 DOI: 10.1242/bio.027391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Drosophila lethal giant larvae (lgl) encodes a conserved tumor suppressor with established roles in cell polarity, asymmetric division, and proliferation control. Lgl's human orthologs, HUGL1 and HUGL2, are altered in human cancers, however, its mechanistic role as a tumor suppressor remains poorly understood. Based on a previously established connection between Lgl and Fragile X protein (FMRP), a miRNA-associated translational regulator, we hypothesized that Lgl may exert its role as a tumor suppressor by interacting with the miRNA pathway. Consistent with this model, we found that lgl is a dominant modifier of Argonaute1 overexpression in the eye neuroepithelium. Using microarray profiling we identified a core set of ten miRNAs that are altered throughout tumorigenesis in Drosophila lgl mutants. Among these are several miRNAs previously linked to human cancers including miR-9a, which we found to be downregulated in lgl neuroepithelial tissues. To determine whether miR-9a can act as an effector of Lgl in vivo, we overexpressed it in the context of lgl knock-down by RNAi and found it able to reduce the overgrowth phenotype caused by Lgl loss in epithelia. Furthermore, cross-comparisons between miRNA and mRNA profiling in lgl mutant tissues and human breast cancer cells identified thrombospondin (tsp) as a common factor altered in both fly and human breast cancer tumorigenesis models. Our work provides the first evidence of a functional connection between Lgl and the miRNA pathway, demonstrates that miR-9a mediates Lgl's role in restricting epithelial proliferation, and provides novel insights into pathways controlled by Lgl during tumor progression. Summary: Mir-9a overexpression can suppress the overgrowth phenotype caused by Lgl knock-down in epithelia. Gene profiling identifies pathways dysregulated in lgl mutants and shared features between flies and human cancer cells.
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Affiliation(s)
- Scott G Daniel
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Atlantis D Russ
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA.,Genetics Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ 85721, USA.,Arizona Cancer Center, University of Arizona, Tucson, AZ 85721, USA
| | - Kathryn M Guthridge
- Cell Cycle and Development Laboratory, Research Division, Peter MacCallum Cancer Center, Melbourne, Victoria 3000, Australia
| | - Ammad I Raina
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Patricia S Estes
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Linda M Parsons
- Cell Cycle and Development Laboratory, Research Division, Peter MacCallum Cancer Center, Melbourne, Victoria 3000, Australia.,Department of Genetics, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Helena E Richardson
- Cell Cycle and Development Laboratory, Research Division, Peter MacCallum Cancer Center, Melbourne, Victoria 3000, Australia.,Sir Peter MacCallum Department of Oncology, Department of Anatomy & Neuroscience, Department of Biochemistry & Molecular Biology, University of Melbourne, Melbourne, Victoria 3000, Australia.,Department of Biochemistry & Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Joyce A Schroeder
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA.,Genetics Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ 85721, USA.,Arizona Cancer Center, University of Arizona, Tucson, AZ 85721, USA
| | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA .,Genetics Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ 85721, USA.,Arizona Cancer Center, University of Arizona, Tucson, AZ 85721, USA
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31
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Sollazzo M, Genchi C, Paglia S, Di Giacomo S, Pession A, de Biase D, Grifoni D. High MYC Levels Favour Multifocal Carcinogenesis. Front Genet 2018; 9:612. [PMID: 30619451 PMCID: PMC6297171 DOI: 10.3389/fgene.2018.00612] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 11/20/2018] [Indexed: 02/05/2023] Open
Abstract
The term "field cancerisation" describes the formation of tissue sub-areas highly susceptible to multifocal tumourigenesis. In the earlier stages of cancer, cells may indeed display a series of molecular alterations that allow them to proliferate faster, eventually occupying discrete tissue regions with irrelevant morphological anomalies. This behaviour recalls cell competition, a process based on a reciprocal fitness comparison: when cells with a growth advantage arise in a tissue, they are able to commit wild-type neighbours to death and to proliferate at their expense. It is known that cells expressing high MYC levels behave as super-competitors, able to kill and replace less performant adjacent cells; given MYC upregulation in most human cancers, MYC-mediated cell competition is likely to pioneer field cancerisation. Here we show that MYC overexpression in a sub-territory of the larval wing epithelium of Drosophila is sufficient to trigger a number of cellular responses specific to mammalian pre-malignant tissues. Moreover, following induction of different second mutations, high MYC-expressing epithelia were found to be susceptible to multifocal growth, a hallmark of mammalian pre-cancerous fields. In summary, our study identified an early molecular alteration implicated in field cancerisation and established a genetically amenable model which may help study the molecular basis of early carcinogenesis.
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Milgrom-Hoffman M, Humbert PO. Regulation of cellular and PCP signalling by the Scribble polarity module. Semin Cell Dev Biol 2017; 81:33-45. [PMID: 29154823 DOI: 10.1016/j.semcdb.2017.11.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 11/11/2017] [Accepted: 11/13/2017] [Indexed: 10/18/2022]
Abstract
Since the first identification of the Scribble polarity module proteins as a new class of tumour suppressors that regulate both cell polarity and proliferation, an increasing amount of evidence has uncovered a broader role for Scribble, Dlg and Lgl in the control of fundamental cellular functions and their signalling pathways. Here, we review these findings as well as discuss more specifically the role of the Scribble module in PCP signalling.
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Affiliation(s)
- Michal Milgrom-Hoffman
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Patrick O Humbert
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia; Department of Biochemistry & Molecular Biology, University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia.
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Gupta RP, Bajpai A, Sinha P. Selector genes display tumor cooperation and inhibition in Drosophila epithelium in a developmental context-dependent manner. Biol Open 2017; 6:1581-1591. [PMID: 29141951 PMCID: PMC5703612 DOI: 10.1242/bio.027821] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
During animal development, selector genes determine identities of body segments and those of individual organs. Selector genes are also misexpressed in cancers, although their contributions to tumor progression per se remain poorly understood. Using a model of cooperative tumorigenesis, we show that gain of selector genes results in tumor cooperation, but in only select developmental domains of the wing, haltere and eye-antennal imaginal discs of Drosophila larva. Thus, the field selector, Eyeless (Ey), and the segment selector, Ultrabithorax (Ubx), readily cooperate to bring about neoplastic transformation of cells displaying somatic loss of the tumor suppressor, Lgl, but in only those developmental domains that express the homeo-box protein, Homothorax (Hth), and/or the Zinc-finger protein, Teashirt (Tsh). In non-Hth/Tsh-expressing domains of these imaginal discs, however, gain of Ey in lgl- somatic clones induces neoplastic transformation in the distal wing disc and haltere, but not in the eye imaginal disc. Likewise, gain of Ubx in lgl- somatic clones induces transformation in the eye imaginal disc but not in its endogenous domain, namely, the haltere imaginal disc. Our results reveal that selector genes could behave as tumor drivers or inhibitors depending on the tissue contexts of their gains.
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Affiliation(s)
- Ram Prakash Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Anjali Bajpai
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Pradip Sinha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
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Di Giacomo S, Sollazzo M, de Biase D, Ragazzi M, Bellosta P, Pession A, Grifoni D. Human Cancer Cells Signal Their Competitive Fitness Through MYC Activity. Sci Rep 2017; 7:12568. [PMID: 28974715 PMCID: PMC5626713 DOI: 10.1038/s41598-017-13002-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 09/13/2017] [Indexed: 02/08/2023] Open
Abstract
MYC-mediated cell competition is a cell-cell interaction mechanism known to play an evolutionary role during development from Drosophila to mammals. Cells expressing low levels of MYC, called losers, are committed to die by nearby cells with high MYC activity, called winners, that overproliferate to compensate for cell loss, so that the fittest cells be selected for organ formation. Given MYC's consolidated role in oncogenesis, cell competition is supposed to be relevant to cancer, but its significance in human malignant contexts is largely uncharacterised. Here we show stereotypical patterns of MYC-mediated cell competition in human cancers: MYC-upregulating cells and apoptotic cells were indeed repeatedly found at the tumour-stroma interface and within the tumour parenchyma. Cell death amount in the stromal compartment and MYC protein level in the tumour were highly correlated regardless of tumour type and stage. Moreover, we show that MYC modulation in heterotypic co-cultures of human cancer cells is sufficient as to subvert their competitive state, regardless of genetic heterogeneity. Altogether, our findings suggest that the innate role of MYC-mediated cell competition in development is conserved in human cancer, with malignant cells using MYC activity to colonise the organ at the expense of less performant neighbours.
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Affiliation(s)
- Simone Di Giacomo
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, Bologna, 40126, Italy.
| | - Manuela Sollazzo
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, Bologna, 40126, Italy
| | - Dario de Biase
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, Bologna, 40126, Italy
| | - Moira Ragazzi
- Pathology Unit, IRCCS Arcispedale Santa Maria Nuova, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Paola Bellosta
- Center for Integrate Biology (CIBIO), University of Trento, Via Sommarive 9, Povo, (TN), 38123, Italy
| | - Annalisa Pession
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, Bologna, 40126, Italy
| | - Daniela Grifoni
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, Bologna, 40126, Italy.
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Tsuboi A, Umetsu D, Kuranaga E, Fujimoto K. Inference of Cell Mechanics in Heterogeneous Epithelial Tissue Based on Multivariate Clone Shape Quantification. Front Cell Dev Biol 2017; 5:68. [PMID: 28824908 PMCID: PMC5540905 DOI: 10.3389/fcell.2017.00068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 07/05/2017] [Indexed: 12/16/2022] Open
Abstract
Cell populations in multicellular organisms show genetic and non-genetic heterogeneity, even in undifferentiated tissues of multipotent cells during development and tumorigenesis. The heterogeneity causes difference of mechanical properties, such as, cell bond tension or adhesion, at the cell–cell interface, which determine the shape of clonal population boundaries via cell sorting or mixing. The boundary shape could alter the degree of cell–cell contacts and thus influence the physiological consequences of sorting or mixing at the boundary (e.g., tumor suppression or progression), suggesting that the cell mechanics could help clarify the physiology of heterogeneous tissues. While precise inference of mechanical tension loaded at each cell–cell contacts has been extensively developed, there has been little progress on how to distinguish the population-boundary geometry and identify the cause of geometry in heterogeneous tissues. We developed a pipeline by combining multivariate analysis of clone shape with tissue mechanical simulations. We examined clones with four different genotypes within Drosophila wing imaginal discs: wild-type, tartan (trn) overexpression, hibris (hbs) overexpression, and Eph RNAi. Although the clones were previously known to exhibit smoothed or convoluted morphologies, their mechanical properties were unknown. By applying a multivariate analysis to multiple criteria used to quantify the clone shapes based on individual cell shapes, we found the optimal criteria to distinguish not only among the four genotypes, but also non-genetic heterogeneity from genetic one. The efficient segregation of clone shape enabled us to quantitatively compare experimental data with tissue mechanical simulations. As a result, we identified the mechanical basis contributed to clone shape of distinct genotypes. The present pipeline will promote the understanding of the functions of mechanical interactions in heterogeneous tissue in a non-invasive manner.
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Affiliation(s)
- Alice Tsuboi
- Laboratory of Theoretical Biology, Department of Biological Sciences, Osaka UniversityToyonaka, Japan
| | - Daiki Umetsu
- Laboratory of Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku UniversitySendai, Japan
| | - Erina Kuranaga
- Laboratory of Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku UniversitySendai, Japan
| | - Koichi Fujimoto
- Laboratory of Theoretical Biology, Department of Biological Sciences, Osaka UniversityToyonaka, Japan
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Development of an optimized synthetic Notch receptor as an in vivo cell-cell contact sensor. Proc Natl Acad Sci U S A 2017; 114:5467-5472. [PMID: 28490499 DOI: 10.1073/pnas.1703205114] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Detection and manipulation of direct cell-cell contact in complex tissues is a fundamental and challenging problem in many biological studies. Here, we report an optimized Notch-based synthetic receptor (synNQ) useful to study direct cell-cell interactions in Drosophila With the synNQ system, cells expressing a synthetic receptor, which contains Notch activation machinery and a downstream transcriptional activator, QF, are activated by a synthetic GFP ligand expressed by contacting neighbor cells. To avoid cis-inhibition, mutually exclusive expression of the synthetic ligand and receptor is achieved using the "flippase-out" system. Expression of the synthetic GFP ligand is controlled by the Gal4/UAS system for easy and broad applications. Using synNQ, we successfully visualized cell-cell interactions within and between most fly tissues, revealing previously undocumented cell-cell contacts. Importantly, in addition to detection of cells in contact with one another, synNQ allows for genetic manipulation in all cells in contact with a targeted cell population, which we demonstrate in the context of cell competition in developing wing disks. Altogether, the synNQ genetic system will enable a broad range of studies of cell contact in developmental biology.
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Di Giacomo S, Sollazzo M, Paglia S, Grifoni D. MYC, Cell Competition, and Cell Death in Cancer: The Inseparable Triad. Genes (Basel) 2017; 8:genes8040120. [PMID: 28420161 PMCID: PMC5406867 DOI: 10.3390/genes8040120] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/09/2017] [Accepted: 04/12/2017] [Indexed: 01/07/2023] Open
Abstract
Deregulation of MYC family proteins in cancer is associated with a global reprogramming of gene expression, ultimately promoting glycolytic pathways, cell growth, and proliferation. It is well known that MYC upregulation triggers cell-autonomous apoptosis in normal tissues, while frankly malignant cells develop resistance to apoptotic stimuli, partly resulting from MYC addiction. As well as inducing cell-autonomous apoptosis, MYC upregulation is able to trigger non cell-autonomous apoptotic death through an evolutionarily conserved mechanism known as “cell competition”. With regard to this intimate and dual relationship between MYC and cell death, recent evidence obtained in Drosophila models of cancer has revealed that, in early tumourigenesis, MYC upregulation guides the clonal expansion of mutant cells, while the surrounding tissue undergoes non-cell autonomous death. Apoptosis inhibition in this context was shown to restrain tumour growth and to restore a wild-type phenotype. This suggests that cell-autonomous and non cell-autonomous apoptosis dependent on MYC upregulation may shape tumour growth in different ways, soliciting the need to reconsider the role of cell death in cancer in the light of this new level of complexity. Here we review recent literature about MYC and cell competition obtained in Drosophila, with a particular emphasis on the relevance of cell death to cell competition and, more generally, to cancer. Possible implications of these findings for the understanding of mammalian cancers are also discussed.
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Affiliation(s)
- Simone Di Giacomo
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
| | - Manuela Sollazzo
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
| | - Simona Paglia
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
| | - Daniela Grifoni
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
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Liggett LA, DeGregori J. Changing mutational and adaptive landscapes and the genesis of cancer. Biochim Biophys Acta Rev Cancer 2017; 1867:84-94. [PMID: 28167050 DOI: 10.1016/j.bbcan.2017.01.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 01/27/2017] [Accepted: 01/28/2017] [Indexed: 12/31/2022]
Abstract
By the time the process of oncogenesis has produced an advanced cancer, tumor cells have undergone extensive evolution. The cellular phenotypes resulting from this evolution have been well studied, and include accelerated growth rates, apoptosis resistance, immortality, invasiveness, and immune evasion. Yet with all of our current knowledge of tumor biology, the details of early oncogenesis have been difficult to observe and understand. Where different oncogenic mutations may work together to enhance the survival of a tumor cell, in isolation they are often pro-apoptotic, pro-differentiative or pro-senescent, and therefore often, somewhat paradoxically, disadvantageous to a cell. It is also becoming clear that somatic mutations, including those in known oncogenic drivers, are common in tissues starting at a young age. These observations raise the question: how do we largely avoid cancer for most of our lives? Here we propose that evolutionary forces can help explain this paradox. As humans and other organisms age or experience external insults such as radiation or smoking, the structure and function of tissues progressively degrade, resulting in altered stem cell niche microenvironments. As tissue integrity declines, it becomes less capable of supporting and maintaining resident stem cells. These stem cells then find themselves in a microenvironment to which they are poorly adapted, providing a competitive advantage to those cells that can restore their functionality and fitness through mutations or epigenetic changes. The resulting oncogenic clonal expansions then increase the odds of further cancer progression. Understanding how the causes of cancer, such as aging or smoking, affect tissue microenvironments to control the impact of mutations on somatic cell fitness can help reconcile the discrepancy between marked mutation accumulation starting early in life and the somatic evolution that leads to cancer at advanced ages or following carcinogenic insults. This article is part of a Special Issue entitled: Evolutionary principles - heterogeneity in cancer?, edited by Dr. Robert A. Gatenby.
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Affiliation(s)
- L Alexander Liggett
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, United States
| | - James DeGregori
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, United States; Integrated Department of Immunology, University of Colorado School of Medicine, Aurora, CO 80045, United States; Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO 80045, United States; Department of Medicine, Section of Hematology, University of Colorado School of Medicine, Aurora, CO 80045, United States.
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Affiliation(s)
- Cristina Clavería
- Cardiovascular Development Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain;
| | - Miguel Torres
- Cardiovascular Development Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain;
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40
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Abstract
Tissue growth and regeneration are autonomous, stem-cell-mediated processes in which stem cells within the organ self-renew and differentiate to create new cells, leading to new tissue. The processes of growth and regeneration require communication and interplay between neighboring cells. In particular, cell competition, which is a process in which viable cells are actively eliminated by more competitive cells, has been increasingly implicated to play an important role. Here, we discuss the existing literature regarding the current landscape of cell competition, including classical pathways and models, fitness fingerprint mechanisms, and immune system mechanisms of cell competition. We further discuss the clinical relevance of cell competition in the physiological processes of tissue growth and regeneration, highlighting studies in clinically important disease models, including oncological, neurological, and cardiovascular diseases.
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Affiliation(s)
- Rajan Gogna
- Institut für Zellbiologie, University of Bern, CH-3012 Bern, Switzerland; .,Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire 03766
| | - Kevin Shee
- Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire 03766
| | - Eduardo Moreno
- Institut für Zellbiologie, University of Bern, CH-3012 Bern, Switzerland;
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41
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Cell Competition and Its Role in the Regulation of Cell Fitness from Development to Cancer. Dev Cell 2016; 38:621-34. [DOI: 10.1016/j.devcel.2016.08.012] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/01/2016] [Accepted: 08/22/2016] [Indexed: 12/26/2022]
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Tamori Y, Suzuki E, Deng WM. Epithelial Tumors Originate in Tumor Hotspots, a Tissue-Intrinsic Microenvironment. PLoS Biol 2016; 14:e1002537. [PMID: 27584724 PMCID: PMC5008749 DOI: 10.1371/journal.pbio.1002537] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 07/27/2016] [Indexed: 12/28/2022] Open
Abstract
Malignant tumors are caused by uncontrolled proliferation of transformed mutant cells that have lost the ability to maintain tissue integrity. Although a number of causative genetic backgrounds for tumor development have been discovered, the initial steps mutant cells take to escape tissue integrity and trigger tumorigenesis remain elusive. Here, we show through analysis of conserved neoplastic tumor-suppressor genes (nTSGs) in Drosophila wing imaginal disc epithelia that tumor initiation depends on tissue-intrinsic local cytoarchitectures, causing tumors to consistently originate in a specific region of the tissue. In this “tumor hotspot” where cells constitute a network of robust structures on their basal side, nTSG-deficient cells delaminate from the apical side of the epithelium and begin tumorigenic overgrowth by exploiting endogenous Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling activity. Conversely, in other regions, the “tumor coldspot” nTSG-deficient cells are extruded toward the basal side and undergo apoptosis. When the direction of delamination is reversed through suppression of RhoGEF2, an activator of the Rho family small GTPases, and JAK/STAT is activated ectopically in these coldspot nTSG-deficient cells, tumorigenesis is induced. These data indicate that two independent processes, apical delamination and JAK/STAT activation, are concurrently required for the initiation of nTSG-deficient-induced tumorigenesis. Given the conservation of the epithelial cytoarchitecture, tumorigenesis may be generally initiated from tumor hotspots by a similar mechanism. A genetic study in Drosophila reveals a mechanism of tumorigenesis by which pro-tumor cells initiate dysplastic tumor growth at specific "hotspot" locations in epithelial tissues. Transformed mutant cells (pro-tumor cells) can evolve through a multistep process in which they become tumorigenic and invasive. Many genes that are involved in the different steps towards cancer development have been identified; however, how certain mutant cells destroy normal tissue organization and undergo uncontrolled proliferation during the initial stages of this process remains largely unclear. Using the epithelial tissue of the wing imaginal discs of the fruit fly (Drosophila melanogaster) larvae as a model system, we have analyzed these initial stages of inducing tumors by depletion of a neoplastic tumor suppressor gene (nTSG). We discovered that these tumors always originate from specific regions of the epithelial tissue of the wing disc. We show that in other regions that we dubbed “tumor coldspots” and that lack specific cellular structures, pro-tumor cells are eliminated from the epithelial tissue by the surrounding cells. However, in “tumor hotspots,” cells constitute specific structures in their basal side, and we found that pro-tumor cells successfully avoid potential elimination and deviate from the apical side of the tissue, initiating tumorous overgrowth. Our findings reveal the molecular and cellular mechanisms underlying the initial steps of tumorigenesis at tumor hotspots in the Drosophila imaginal wing discs.
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Affiliation(s)
- Yoichiro Tamori
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America
- Structural Biology Center, National Institute of Genetics and Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), 1111 Yata, Mishima, Japan
- * E-mail: (YT); (WMD)
| | - Emiko Suzuki
- Structural Biology Center, National Institute of Genetics and Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), 1111 Yata, Mishima, Japan
| | - Wu-Min Deng
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America
- * E-mail: (YT); (WMD)
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An Ectopic Network of Transcription Factors Regulated by Hippo Signaling Drives Growth and Invasion of a Malignant Tumor Model. Curr Biol 2016; 26:2101-13. [DOI: 10.1016/j.cub.2016.06.035] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 05/21/2016] [Accepted: 06/16/2016] [Indexed: 12/19/2022]
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Romani P, Gargiulo G, Cavaliere V. The ecdysone receptor signalling regulates microvilli formation in follicular epithelial cells. Cell Mol Life Sci 2016; 73:409-25. [PMID: 26223269 PMCID: PMC11108565 DOI: 10.1007/s00018-015-1999-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 07/03/2015] [Accepted: 07/22/2015] [Indexed: 11/27/2022]
Abstract
Epithelial morphogenesis contributes greatly to the development and homeostasis of the organs and body parts. Here, we analysed the consequences of impaired ecdysone receptor (EcR) signalling in the Drosophila follicular epithelium. Besides governing cell growth, the three EcR isoforms act redundantly in controlling follicle cell positioning. Flattening of the microvilli and an aberrant actin cytoskeleton arise from defective EcR signalling in follicle cells, and these defects impact on the organisation of the oocyte membrane. We found that this signalling governs a complex molecular network since its impairment affects key molecules as atypical protein kinase C and activated Moesin. Interestingly, the activity of the transcription factor Tramtrack69 isoform is required for microvilli and their actin core morphogenesis as well as for follicle cell positioning. In conclusion, our findings provide evidence of novel roles for EcR signalling and Tramtrack69 transcription factor in controlling stage-specific differentiation events that take place in the follicular epithelium.
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Affiliation(s)
- Patrizia Romani
- Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Selmi, 3, 40126, Bologna, Italy.
| | - Giuseppe Gargiulo
- Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Selmi, 3, 40126, Bologna, Italy
| | - Valeria Cavaliere
- Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Selmi, 3, 40126, Bologna, Italy.
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45
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Abstract
Epithelia form intelligent, dynamic barriers between the external environment and an organism's interior. Intercellular cadherin-based adhesions adapt and respond to mechanical forces and cell density, while tight junctions flexibly control diffusion both within the plasma membrane and between adjacent cells. Epithelial integrity and homeostasis are of central importance to survival, and mechanisms have evolved to ensure these processes are maintained during growth and in response to damage. For instance, cell competition surveys the fitness of cells within epithelia and removes the less fit; extrusion or delamination can remove apoptotic or defective cells from the epithelial sheet and can restore homeostasis when an epithelial layer becomes too crowded; spindle orientation ensures two-dimensional growth in simple epithelia and controls stratification in complex epithelia; and transition to a mesenchymal phenotype enables active escape from an epithelial layer. This review will discuss these various mechanisms and consider how they are subverted in disease.
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Affiliation(s)
- Ian G Macara
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Richard Guyer
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Graham Richardson
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Yongliang Huo
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Syed M Ahmed
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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46
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Grifoni D, Sollazzo M, Fontana E, Froldi F, Pession A. Multiple strategies of oxygen supply in Drosophila malignancies identify tracheogenesis as a novel cancer hallmark. Sci Rep 2015; 5:9061. [PMID: 25762498 PMCID: PMC4357021 DOI: 10.1038/srep09061] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/16/2015] [Indexed: 12/20/2022] Open
Abstract
Angiogenesis is the term used to describe all the alterations in blood vessel growth induced by a tumour mass following hypoxic stress. The occurrence of multiple strategies of vessel recruitment favours drug resistance, greatly complicating the treatment of certain tumours. In Drosophila, oxygen is conveyed to the internal organs by the tracheal system, a closed tubular network whose role in cancer growth is so far unexplored. We found that, as observed in human cancers, Drosophila malignant cells suffer from oxygen shortage, release pro-tracheogenic factors, co-opt nearby vessels and get incorporated into the tracheal walls. We also found that the parallelisms observed in cellular behaviours are supported by genetic and molecular conservation. Finally, we identified a molecular circuitry associated with the differentiation of cancer cells into tracheal cells. In summary, our findings identify tracheogenesis as a novel cancer hallmark in Drosophila, further expanding the power of the fly model in cancer research.
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Affiliation(s)
- Daniela Grifoni
- Department of "Farmacia e Biotecnologie", University of Bologna, Bologna, Italy
| | - Manuela Sollazzo
- Department of "Farmacia e Biotecnologie", University of Bologna, Bologna, Italy
| | - Elisabetta Fontana
- Department of "Farmacia e Biotecnologie", University of Bologna, Bologna, Italy
| | - Francesca Froldi
- Department of "Farmacia e Biotecnologie", University of Bologna, Bologna, Italy
| | - Annalisa Pession
- Department of "Farmacia e Biotecnologie", University of Bologna, Bologna, Italy
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47
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Grifoni D, Bellosta P. Drosophila Myc: A master regulator of cellular performance. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:570-81. [PMID: 25010747 DOI: 10.1016/j.bbagrm.2014.06.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 06/26/2014] [Accepted: 06/30/2014] [Indexed: 11/25/2022]
Abstract
The identification of the Drosophila homolog of the human MYC oncogene has fostered a series of studies aimed to address its functions in development and cancer biology. Due to its essential roles in many fundamental biological processes it is hard to imagine a molecular mechanism in which MYC function is not required. For this reason, the easily manipulated Drosophila system has greatly helped in the dissection of the genetic and molecular pathways that regulate and are regulated by MYC function. In this review, we focus on studies of MYC in the fruitfly with particular emphasis on metabolism and cell competition, highlighting the contributions of this model system in the last decade to our understanding of MYC's complex biological nature. This article is part of a Special Issue entitled: Myc proteins in cell biology and pathology.
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Affiliation(s)
- Daniela Grifoni
- Department of "Farmacia e Biotecnologie", University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
| | - Paola Bellosta
- Department of "Bioscienze", University of Milan, Via Celoria 26, 20133 Milan, Italy.
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Abstract
A conventional view of development is that cells cooperate to build an organism. However, based on studies of Drosophila, it has been known for years that viable cells can be eliminated by their neighbours through a process termed cell competition. New studies in mammals have revealed that this process is universal and that many factors and mechanisms are conserved. During cell competition, cells with lower translation rates or those with lower levels of proteins involved in signal transduction, polarity and cellular growth can survive in a homogenous environment but are killed when surrounded by cells of higher fitness. Here, we discuss recent advances in the field as well as the mechanistic steps involved in this phenomenon, which have shed light on how and why cell competition exists in developing and adult organisms.
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Affiliation(s)
- Marc Amoyel
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, 550 First Avenue, MSB 497B, New York, NY 10016, USA
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Johnston LA. Socializing with MYC: cell competition in development and as a model for premalignant cancer. Cold Spring Harb Perspect Med 2014; 4:a014274. [PMID: 24692189 DOI: 10.1101/cshperspect.a014274] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Studies in Drosophila and mammals have made it clear that genetic mutations that arise in somatic tissues are rapidly recognized and eliminated, suggesting that cellular fitness is tightly monitored. During development, damaged, mutant, or otherwise unfit cells are prevented from contributing to the tissue and are instructed to die, whereas healthy cells benefit and populate the animal. This cell selection process, known as cell competition, eliminates somatic genetic heterogeneity and promotes tissue fitness during development. Yet cell competition also has a dark side. Super competition can be exploited by incipient cancers to subvert cellular cooperation and promote selfish behavior. Evidence is accumulating that MYC plays a key role in regulation of social behavior within tissues. Given the high number of tumors with deregulated MYC, studies of cell competition promise to yield insight into how the local environment yields to and participates in the early stages of tumor formation.
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Affiliation(s)
- Laura A Johnston
- Department of Genetics and Development, Columbia University Medical Center, New York, New York 10032
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Patel PH, Edgar BA. Tissue design: how Drosophila tumors remodel their neighborhood. Semin Cell Dev Biol 2014; 28:86-95. [PMID: 24685612 DOI: 10.1016/j.semcdb.2014.03.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 03/03/2014] [Indexed: 12/24/2022]
Abstract
Drosophila genetics has long been appreciated as a powerful approach for discovering the normal functions of genes that act as oncogenes and tumor suppressors in human cancer. Recent studies have also highlighted its advantages for deciphering how such genes function during tumorigenesis itself. Here we detail studies relating to how tumors, generated in developing organs and adult stem cell-based tissues, remodel the tissue landscape to their benefit. Like mammalian tumors, insect tumors can dissolve extracellular matrix, recruit blood cells, migrate and invade other tissues. While much is known about how mammalian fibroblasts, immune cells and vasculature promote late tumorigenesis, less is understood about the very earliest stages of tumor development in mammals. Because Drosophila has fewer mitotic cells and a simpler tissue architecture, it affords easy detection and analysis of early clonal tumor growth. Drosophila studies have revealed both cooperative and competitive interactions between tumor and normal cells during early tumor growth. During development, these interactions typically occur with other proliferative progenitor cells, but in adult stem cell-based tissues, the stem cell niche can fuel tumor growth.
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Affiliation(s)
- Parthive H Patel
- German Cancer Research Center (DKFZ) and Center for Molecular Biology Heidelberg (ZMBH) Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany.
| | - Bruce A Edgar
- German Cancer Research Center (DKFZ) and Center for Molecular Biology Heidelberg (ZMBH) Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany.
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