• Open Access

Caveolins in rhabdomyosarcoma


Alessandro FANZANI, Department of Biomedical Sciences and Biotechnologies, Interuniversity Institute of Myology (IIM), University of Brescia, viale Europa 11, 25123 Brescia, Italy. Tel.: +39-030-3717567 Fax: +39-030-3701157 E-mail: fanzani@med.unibs.it


  • • Introduction
  • • Caveolae and caveolins
    • - Caveolins as scaffolding proteins
    • - Impact of the lack of caveolins in the whole body physiology
    • - Relevance of Cav-1 as tumour conditional gene
    • - Role of caveolins in skeletal muscle
  • • Histopathological, genetical and molecular signatures of RMS
    • - Embryonal RMS
    • - Alveolar RMS
    • - Principal pathways and targets deregulated in RMS
    • - Animal models and human syndromes associated to RMS
    • - Origins of RMS
  • • Expression of caveolins in RMS tumours    and cell lines
  • • Future perspectives: assessing the role    of caveolins in RMS tumour progression
    • - Cav-1 and p53 signalling
    • - Cav-1 and multiple control of receptorial systems for growth factors
    • - Cav-1 and RAS/ERK signalling
    • - Caveolins and TGF-β/myostatin signalling
    • - Cav-1 and HGF/cMET signalling
    • - Caveolins and RAGE signalling
  • • Conclusions

Caveolins are scaffolding proteins that play a pivotal role in numerous processes, including caveolae biogenesis, vesicular transport, cholesterol homeostasis and regulation of signal transduction. There are three different isoforms (Cav-1, -2 and -3) that form homo- and hetero-aggregates at the plasma membrane and modulate the activity of a number of intracellular binding proteins. Cav-1 and Cav-3, in particular, are respectively expressed in the reserve elements (e.g. satellite cells) and in mature myofibres of skeletal muscle and their expression interplay characterizes the switch from muscle precursors to differentiated elements. Recent findings have shown that caveolins are also expressed in rhabdomyosarcoma, a group of heterogeneous childhood soft-tissue sarcomas in which the cancer cells seem to derive from progenitors that resemble myogenic cells. In this review, we will focus on the role of caveolins in rhabdomyosarcomas and on their potential use as markers of the degree of differentiation in these paediatric tumours. Given that the function of Cav-1 as tumour conditional gene in cancer has been well-established, we will also discuss the relationship between Cav-1 and the progression of rhabdomyosarcoma.