1
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Monti M, Benerini Gatta L, Bugatti M, Pezzali I, Picinoli S, Manfredi M, Lavazza A, Vanella VV, De Giorgis V, Zanatta L, Missale F, Lonardi S, Zanetti B, Bozzoni G, Cadei M, Abate A, Vergani B, Balzarini P, Battocchio S, Facco C, Turri-Zanoni M, Castelnuovo P, Nicolai P, Fonsatti E, Leone BE, Marengo E, Sigala S, Ronca R, Perego M, Lombardi D, Vermi W. Novel cellular systems unveil mucosal melanoma initiating cells and a role for PI3K/Akt/mTOR pathway in mucosal melanoma fitness. J Transl Med 2024; 22:35. [PMID: 38191367 PMCID: PMC10775657 DOI: 10.1186/s12967-023-04784-2] [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: 07/11/2023] [Accepted: 12/04/2023] [Indexed: 01/10/2024] Open
Abstract
BACKGROUND Mucosal Melanomas (MM) are highly aggressive neoplasms arising from mucosal melanocytes. Current treatments offer a limited survival benefit for patients with advanced MM; moreover, the lack of pre-clinical cellular systems has significantly limited the understanding of their immunobiology. METHODS Five novel cell lines were obtained from patient-derived biopsies of MM arising in the sino-nasal mucosa and designated as SN-MM1-5. The morphology, ultrastructure and melanocytic identity of SN-MM cell lines were validated by transmission electron microscopy and immunohistochemistry. Moreover, in vivo tumorigenicity of SN-MM1-5 was tested by subcutaneous injection in NOD/SCID mice. Molecular characterization of SN-MM cell lines was performed by a mass-spectrometry proteomic approach, and their sensitivity to PI3K chemical inhibitor LY294002 was validated by Akt activation, measured by pAkt(Ser473) and pAkt(Thr308) in immunoblots, and MTS assay. RESULTS This study reports the validation and functional characterization of five newly generated SN-MM cell lines. Compared to the normal counterpart, the proteomic profile of SN-MM is consistent with transformed melanocytes showing a heterogeneous degree of melanocytic differentiation and activation of cancer-related pathways. All SN-MM cell lines resulted tumorigenic in vivo and display recurrent structural variants according to aCGH analysis. Of relevance, the microscopic analysis of the corresponding xenotransplants allowed the identification of clusters of MITF-/CDH1-/CDH2 + /ZEB1 + /CD271 + cells, supporting the existence of melanoma-initiating cells also in MM, as confirmed in clinical samples. In vitro, SN-MM cell lines were sensitive to cisplatin, but not to temozolomide. Moreover, the proteomic analysis of SN-MM cell lines revealed that RICTOR, a subunit of mTORC2 complex, is the most significantly activated upstream regulator, suggesting a relevant role for the PI3K-Akt-mTOR pathway in these neoplasms. Consistently, phosphorylation of NDRG1 and Akt activation was observed in SN-MM, the latter being constitutive and sustained by PTEN loss in SN-MM2 and SN-MM3. The cell viability impairment induced by LY294002 confirmed a functional role for the PI3K-Akt-mTOR pathway in SN-MM cell lines. CONCLUSIONS Overall, these novel and unique cellular systems represent relevant experimental tools for a better understanding of the biology of these neoplasms and, as an extension, to MM from other sites.
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Affiliation(s)
- Matilde Monti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Luisa Benerini Gatta
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Histocompatibility Laboratory "Vittorio Mero", Department of Transfusion Medicine, ASST Spedali Civili Di Brescia, Brescia, Italy
| | - Mattia Bugatti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Irene Pezzali
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Sara Picinoli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Marcello Manfredi
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Center for Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy
| | - Antonio Lavazza
- Istituto Zooprofilattico Sperimentale Della Lombardia E Dell'Emilia-Romagna "Bruno Ubertini", Brescia, Italy
| | - Virginia Vita Vanella
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Center for Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy
| | - Veronica De Giorgis
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Center for Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy
| | - Lucia Zanatta
- Department of Pathology, Treviso Regional Hospital, Treviso, Italy
| | - Francesco Missale
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Department of Head & Neck Oncology & Surgery Otorhinolaryngology, Antoni Van Leeuwenhoek, Nederlands Kanker Instituut, Amsterdam, The Netherlands
| | - Silvia Lonardi
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Benedetta Zanetti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Giovanni Bozzoni
- Istituto Zooprofilattico Sperimentale Della Lombardia E Dell'Emilia-Romagna "Bruno Ubertini", Brescia, Italy
| | - Moris Cadei
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Andrea Abate
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Barbara Vergani
- Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Piera Balzarini
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Simonetta Battocchio
- Unit of Pathology, Department of Molecular and Translational Medicine, University of Brescia-"ASST Spedali Civili Di Brescia", Brescia, Italy
| | - Carla Facco
- Unit of Pathology, Department of Medicine and Surgery, ASST Sette-Laghi, University of Insubria, Varese, Italy
| | - Mario Turri-Zanoni
- Unit of Otorhinolaryngology and Head & Neck Surgery, Department of Biotechnology and Life Sciences, ASST Sette Laghi, University of Insubria, Varese, Italy
| | - Paolo Castelnuovo
- Unit of Otorhinolaryngology and Head & Neck Surgery, Department of Biotechnology and Life Sciences, ASST Sette Laghi, University of Insubria, Varese, Italy
| | - Piero Nicolai
- Section of Otorhinolaryngology-Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
| | - Ester Fonsatti
- Medical Oncology and Immunotherapy, University Hospital of Siena, Istituto Toscano Tumori, Siena, Italy
| | | | - Emilio Marengo
- Department of Sciences and Technological Innovation, University of Piemonte Orientale, Alessandria, Italy
| | - Sandra Sigala
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Roberto Ronca
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | | | - Davide Lombardi
- Unit of Otorhinolaryngology - Head and Neck Surgery, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy
| | - William Vermi
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA.
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy.
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2
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Torices L, Nunes-Xavier CE, López JI, Pulido R. Novel anti-PTEN C2 domain monoclonal antibodies to analyse the expression and function of PTEN isoform variants. PLoS One 2023; 18:e0289369. [PMID: 37527256 PMCID: PMC10393154 DOI: 10.1371/journal.pone.0289369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 07/17/2023] [Indexed: 08/03/2023] Open
Abstract
PTEN is a major tumor suppressor gene frequently mutated in human tumors, and germline PTEN gene mutations are the molecular diagnostic of PTEN Hamartoma Tumor Syndrome (PHTS), a heterogeneous disorder that manifests with multiple hamartomas, cancer predisposition, and neurodevelopmental alterations. A diversity of translational and splicing PTEN isoforms exist, as well as PTEN C-terminal truncated variants generated by disease-associated nonsense mutations. However, most of the available anti-PTEN monoclonal antibodies (mAb) recognize epitopes at the PTEN C-terminal tail, which may introduce a bias in the analysis of the expression of PTEN isoforms and variants. We here describe the generation and precise characterization of anti-PTEN mAb recognizing the PTEN C2-domain, and their use to monitor the expression and function of PTEN isoforms and PTEN missense and nonsense mutations associated to disease. These anti-PTEN C2 domain mAb are suitable to study the pathogenicity of PTEN C-terminal truncations that retain stability and function but have lost the PTEN C-terminal epitopes. The use of well-defined anti-PTEN mAb recognizing distinct PTEN regions, as the ones here described, will help to understand the deleterious effects of specific PTEN mutations in human disease.
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Affiliation(s)
- Leire Torices
- Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Caroline E Nunes-Xavier
- Biobizkaia Health Research Institute, Barakaldo, Spain
- Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - José I López
- Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Rafael Pulido
- Biobizkaia Health Research Institute, Barakaldo, Spain
- Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
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3
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Kato T. Immunofluorescence Detection of Plasma Membranous PTEN in Cultured Cells. J Histochem Cytochem 2022; 70:289-297. [PMID: 35199573 PMCID: PMC8971685 DOI: 10.1369/00221554221082539] [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: 08/31/2021] [Accepted: 02/04/2022] [Indexed: 11/22/2022] Open
Abstract
PTEN is a well-known tumor suppressor with various functions that depend on its intracellular localization. Green fluorescent protein (GFP)-tagged live-cell images clarified the crucial amino acids needed to regulate the localization of PTEN in cells. However, it currently remains unknown whether GFP itself affects the intracellular localization of PTEN and its mutants, and the establishment of fixed-cell imaging is important for identifying the exact location of PTEN in cells. I herein investigated a number of immunofluorescence strategies for cell fixation, membrane permeabilization, and antigen retrieval. Permeabilization by detergents was necessary to observe nuclear and cytosolic PTEN in paraformaldehyde (PFA)-fixed cells; however, this permeabilization was not always valid. On the other hand, antigen retrieval by the pre-boiled EDTA treatment was useful for detecting plasma membranous PTEN in PFA-fixed cells in the same manner as in in vivo studies. Furthermore, methanol-fixed images of PTEN were consistent with GFP-tagged live-cell images. Two immunofluorescence methods (the PFA-fixed/pre-boiled EDTA treatment and methanol fixation) are applicable to investigations of the intracellular localization of PTEN without a GFP tag in cultured cells. In conclusion, live-cell imaging and appropriate immunofluorescence including a novel antigen retrieval treatment were both useful for detecting the cellular localization of PTEN, particularly at the plasma membrane.
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Affiliation(s)
- Takashi Kato
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Faculty of Pharmacy, Yasuda Women’s University, Hiroshima, Japan
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4
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Luna S, Torices L, Mingo J, Amo L, Rodríguez-Escudero I, Ruiz-Ibarlucea P, Erramuzpe A, Cortés JM, Tejada MI, Molina M, Nunes-Xavier CE, López JI, Cid VJ, Pulido R. A global analysis of the reconstitution of PTEN function by translational readthrough of PTEN pathogenic premature termination codons. Hum Mutat 2021; 42:551-566. [PMID: 33600059 DOI: 10.1002/humu.24186] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/15/2021] [Accepted: 02/14/2021] [Indexed: 12/29/2022]
Abstract
The PTEN tumor suppressor gene is mutated with high incidence in tumors and in the germline of patients with cancer predisposition or with macrocephaly associated with autism. PTEN nonsense mutations generating premature termination codons (PTC) and producing nonfunctional truncated PTEN proteins are frequent in association with human disease. However, there are no studies addressing the restoration of full-length PTEN proteins from the PTC-mutated PTEN gene by translational readthrough. Here, we have performed a global translational and functional readthrough analysis of the complete collection of PTEN PTC somatic or hereditary mutations found in tumors or in the germline of patients (disease-associated PTEN PTCome), and we set standards for the analysis of the potential of readthrough functional reconstitution in disease-relevant genes. Our analysis indicates that prevalent pathogenic PTEN PTC mutations are susceptible to PTEN functional restoration in response to readthrough-inducing compounds. Comprehensive readthrough analyses of disease-associated PTComes will be valuable tools for the implementation of readthrough-based precision interventions in specific groups of patients.
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Affiliation(s)
- Sandra Luna
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Leire Torices
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Janire Mingo
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Laura Amo
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Isabel Rodríguez-Escudero
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | | | - Asier Erramuzpe
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Jesús M Cortés
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
| | - María I Tejada
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - María Molina
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - Caroline E Nunes-Xavier
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - José I López
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Department of Pathology, Cruces University Hospital, Barakaldo, Spain
| | - Víctor J Cid
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - Rafael Pulido
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
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5
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Pulido R, Mingo J, Gaafar A, Nunes-Xavier CE, Luna S, Torices L, Angulo JC, López JI. Precise Immunodetection of PTEN Protein in Human Neoplasia. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a036293. [PMID: 31501265 DOI: 10.1101/cshperspect.a036293] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PTEN is a major tumor-suppressor protein whose expression and biological activity are frequently diminished in sporadic or inherited cancers. PTEN gene deletion or loss-of-function mutations favor tumor cell growth and are commonly found in clinical practice. In addition, diminished PTEN protein expression is also frequently observed in tumor samples from cancer patients in the absence of PTEN gene alterations. This makes PTEN protein levels a potential biomarker parameter in clinical oncology, which can guide therapeutic decisions. The specific detection of PTEN protein can be achieved by using highly defined anti-PTEN monoclonal antibodies (mAbs), characterized with precision in terms of sensitivity for the detection technique, specificity for PTEN binding, and constraints of epitope recognition. This is especially relevant taking into consideration that PTEN is highly targeted by mutations and posttranslational modifications, and different PTEN protein isoforms exist. The precise characterization of anti-PTEN mAb reactivity is an important step in the validation of these reagents as diagnostic and prognostic tools in clinical oncology, including their routine use in analytical immunohistochemistry (IHC). Here, we review the current status on the use of well-defined anti-PTEN mAbs for PTEN immunodetection in the clinical context and discuss their potential usefulness and limitations for a more precise cancer diagnosis and patient benefit.
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Affiliation(s)
- Rafael Pulido
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao 48011, Spain
| | - Janire Mingo
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Ayman Gaafar
- Department of Pathology, Cruces University Hospital, Barakaldo 48903, Spain
| | - Caroline E Nunes-Xavier
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital Radiumhospitalet, Oslo N-0310, Norway
| | - Sandra Luna
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Leire Torices
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Javier C Angulo
- Department of Urology, University Hospital of Getafe, Getafe, Madrid 28904, Spain.,Clinical Department, European University of Madrid, Laureate Universities, Madrid 28904, Spain
| | - José I López
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Department of Pathology, Cruces University Hospital, Barakaldo 48903, Spain.,University of the Basque Country, Leioa 48940, Spain
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6
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Precise definition of PTEN C-terminal epitopes and its implications in clinical oncology. NPJ Precis Oncol 2019; 3:11. [PMID: 30993208 PMCID: PMC6465295 DOI: 10.1038/s41698-019-0083-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 03/05/2019] [Indexed: 02/07/2023] Open
Abstract
Anti-PTEN monoclonal antibodies (mAb) are arising as important tools for immunohistochemistry (IHC) and protein quantification routine analysis in clinical oncology. Although an effort has been made to document the reliability of tumor tissue section immunostaining by anti-PTEN mAb, and to standardize their IHC use in research and in the clinical practice, the precise topological and biochemical definition of the epitope recognized by each mAb has been conventionally overlooked. In this study, six commercial anti-PTEN mAb have been validated and characterized for sensitivity and specificity by IHC and FISH, using a set of prostate and urothelial bladder tumor specimens, and by immunoblot, using PTEN positive and PTEN negative human cell lines. Immunoblot precise epitope mapping, performed using recombinant PTEN variants and mutations, revealed that all mAb recognized linear epitopes of 6–11 amino acid length at the PTEN C-terminus. Tumor-associated or disease-associated mutations at the PTEN C-terminus did not affect subcellular localization or PIP3 phosphatase activity of PTEN in cells, although resulted in specific loss of reactivity for some mAb. Furthermore, specific mimicking-phosphorylation mutations at the PTEN C-terminal region also abolished binding of specific mAb. Our study adds new evidence on the relevance of a precise epitope mapping in the validation of anti-PTEN mAb for their use in the clinics. This will be substantial to provide a more accurate diagnosis in clinical oncology based on PTEN protein expression in tumors and biological fluids.
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7
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A pathogenic role for germline PTEN variants which accumulate into the nucleus. Eur J Hum Genet 2018; 26:1180-1187. [PMID: 29706633 DOI: 10.1038/s41431-018-0155-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/27/2018] [Accepted: 03/30/2018] [Indexed: 11/08/2022] Open
Abstract
The PTEN gene encodes a master regulator protein that exerts essential functions both in the cytoplasm and in the nucleus. PTEN is mutated in the germline of both patients with heterogeneous tumor syndromic diseases, categorized as PTEN hamartoma tumor syndrome (PHTS), and a group affected with autism spectrum disorders (ASD). Previous studies have unveiled the functional heterogeneity of PTEN variants found in both patient cohorts, making functional studies necessary to provide mechanistic insights related to their pathogenicity. Here, we have functionally characterized a PTEN missense variant [c.49C>G; p.(Gln17Glu); Q17E] associated to both PHTS and ASD patients. The PTEN Q17E variant displayed partially reduced PIP3-catalytic activity and normal stability in cells, as shown using S. cerevisiae and mammalian cell experimental models. Remarkably, PTEN Q17E accumulated in the nucleus, in a process involving the PTEN N-terminal nuclear localization sequence. The analysis of additional germline-associated PTEN N-terminal variants illustrated the existence of a PTEN N-terminal region whose targeting in disease causes PTEN nuclear accumulation, in parallel with defects in PIP3-catalytic activity in cells. Our findings highlight the frequent occurrence of PTEN gene mutations targeting PTEN N-terminus whose pathogenicity may be related, at least in part, with the retention of PTEN in the nucleus. This could be important for the implementation of precision therapies for patients with alterations in the PTEN pathway.
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8
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Lusche DF, Buchele EC, Russell KB, Soll BA, Vitolo MI, Klemme MR, Wessels DJ, Soll DR. Overexpressing TPTE2 ( TPIP), a homolog of the human tumor suppressor gene PTEN, rescues the abnormal phenotype of the PTEN-/- mutant. Oncotarget 2018; 9:21100-21121. [PMID: 29765523 PMCID: PMC5940379 DOI: 10.18632/oncotarget.24941] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 03/06/2018] [Indexed: 11/25/2022] Open
Abstract
One possible approach to normalize mutant cells that are metastatic and tumorigenic, is to upregulate a functionally similar homolog of the mutated gene. Here we have explored this hypothesis by generating an overexpressor of TPTE2 (TPIP), a homolog of PTEN, in PTEN-/- mutants, the latter generated by targeted mutagenesis of a human epithelial cell line. Overexpression of TPTE2 normalized phenotypic changes associated with the PTEN mutation. The PTEN-/- -associated changes rescued by overexpressing TPTE2 included 1) accelerated wound healing in the presence or absence of added growth factors (GFs), 2) increased division rates on a 2D substrate in the presence of GFs, 3) adhesion and viability on a 2D substrate in the absence of GFs, 4) viability in a 3D Matrigel model in the absence of GFs and substrate adhesion 5) loss of apoptosis-associated annexin V cell surface binding sites. The results justify further exploration into the possibility that upregulating TPTE2 by a drug may reverse metastatic and tumorigenic phenotypes mediated in part by a mutation in PTEN. This strategy may also be applicable to other tumorigenic mutations in which a homolog to the mutated gene is present and can substitute functionally.
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Affiliation(s)
- Daniel F. Lusche
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - Emma C. Buchele
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - Kanoe B. Russell
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - Benjamin A. Soll
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - Michele I. Vitolo
- Greenebaum Cancer Center, The University of Maryland, Baltimore, Maryland, Baltimore, 21201 MD, USA
| | - Michael R. Klemme
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - Deborah J. Wessels
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
| | - David R. Soll
- Developmental Studies Hybridoma Bank and W.M. Keck Dynamic Image Analysis Facility, Department of Biology, The University of Iowa, Iowa City, 52242 IA, USA
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