title: MURC/cavin-4 Is Co-Expressed with Caveolin-3 in Rhabdomyosarcoma Tumors and Its Silencing Prevents Myogenic Differentiation in the Human Embryonal RD Cell Line.
abstract: The purpose of this study was to investigate whether MURC/cavin-4, a plasma membrane and Z-line associated protein exhibiting an overlapping distribution with Caveolin-3 (Cav-3) in heart and muscle tissues, may be expressed and play a role in rhabdomyosarcoma (RMS), an aggressive myogenic tumor affecting childhood. We found MURC/cavin-4 to be expressed, often concurrently with Cav-3, in mouse and human RMS, as demonstrated through in silico analysis of gene datasets and immunohistochemical analysis of tumor samples. In vitro expression studies carried out using human cell lines and primary mouse tumor cultures showed that expression levels of both MURC/cavin-4 and Cav-3, while being low or undetectable during cell proliferation, became robustly increased during myogenic differentiation, as detected via semi-quantitative RT-PCR and immunoblotting analysis. Furthermore, confocal microscopy analysis performed on human RD and RH30 cell lines confirmed that MURC/cavin-4 mostly marks differentiated cell elements, colocalizing at the cell surface with Cav-3 and labeling myosin heavy chain (MHC) expressing cells. Finally, MURC/cavin-4 silencing prevented the differentiation in the RD cell line, leading to morphological cell impairment characterized by depletion of myogenin, Cav-3 and MHC protein levels. Overall, our data suggest that MURC/cavin-4, especially in combination with Cav-3, may play a consistent role in the differentiation process of RMS.
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy; Interuniversity Institute of Myology (IIM), Rome, Italy.
authors.forename: Fiorella
authors.initials: F
authors.lastname: Faggi
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy; Interuniversity Institute of Myology (IIM), Rome, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Codenotti
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Pietro Luigi
authors.initials: PL
authors.lastname: Poliani
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Cominelli
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Chiarelli
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Colombi
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Marika
authors.initials: M
authors.lastname: Vezzoli
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Monti
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Bono
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tulipano
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Fiorentini
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Zanola
authors.affiliation: Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Harriet P
authors.initials: HP
authors.lastname: Lo
authors.affiliation: Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Parton
authors.affiliation: Department of Pediatrics, Oregon Health & Science University, Portland, OR, United States of America; Children's Cancer Therapy Development Institute, Fort Collins, CO, United States of America.
authors.forename: Charles
authors.initials: C
authors.lastname: Keller
authors.affiliation: Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy; Interuniversity Institute of Myology (IIM), Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Fanzani
mesh_terms: D000818:Animals; D051244:Caveolin 3 / Q000378:metabolism*; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D015870:Gene Expression; D055785:Gene Knockdown Techniques; D006801:Humans; D053208:Kaplan-Meier Estimate; D051379:Mice; D019042:Muscle Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D012208:Rhabdomyosarcoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D033921:Vesicular Transport Proteins
chemical_list: C570060:CAVIN4 protein, human; D051244:Caveolin 3; D009124:Muscle Proteins; D034741:RNA, Small Interfering; D033921:Vesicular Transport Proteins