MVP and vaults: a role in the radiation response
1 Radiation Oncology Department, Hospital Universitario de Gran Canaria Dr Negrín. C/Barranco de La Ballena s/n, 35010, Las Palmas de Gran Canaria, Spain
2 Clinical Sciences Department, Universidad de Las Palmas de Gran Canaria. C/Dr. Pasteur s/n, 35016, Las Palmas de Gran Canaria, Spain
3 Instituto Canario de Investigación del Cáncer, Canary Islands, Spain
4 Radiation Oncology Department, University Hospital Zürich. Raemistrasse 100CH-8091, Zürich, Switzerland
Radiation Oncology 2011, 6:148 doi:10.1186/1748-717X-6-148Published: 31 October 2011
Vaults are evolutionary highly conserved ribonucleoproteins particles with a hollow barrel-like structure. The main component of vaults represents the 110 kDa major vault protein (MVP), whereas two minor vaults proteins comprise the 193 kDa vault poly(ADP-ribose) polymerase (vPARP) and the 240 kDa telomerase-associated protein-1 (TEP-1). Additionally, at least one small and untranslated RNA is found as a constitutive component. MVP seems to play an important role in the development of multidrug resistance. This particle has also been implicated in the regulation of several cellular processes including transport mechanisms, signal transmission and immune responses. Vaults are considered a prognostic marker for different cancer types. The level of MVP expression predicts the clinical outcome after chemotherapy in different tumour types. Recently, new roles have been assigned to MVP and vaults including the association with the insulin-like growth factor-1, hypoxia-inducible factor-1alpha, and the two major DNA double-strand break repair machineries: non-homologous endjoining and homologous recombination. Furthermore, MVP has been proposed as a useful prognostic factor associated with radiotherapy resistance. Here, we review these novel actions of vaults and discuss a putative role of MVP and vaults in the response to radiotherapy.