J Proteome Res. 2007 Mar 6
Proteomic Analysis of the Resistance to Aplidin in Human Cancer Cells.
Gonzalez-Santiago L ,Alfonso P, Suarez Y, Nunez A ,Garcia-Fernandez LF, Alvarez E, Munoz A, Casal JI .
Instituto de Investigaciones Biomedicas "Alberto Sols", Consejo Superior de Investigaciones Cientificas, Universidad Autonoma de Madrid, Arturo Duperier, 4, E-28029 Madrid, Spain, PharmaMar S.A., E-28770 Colmenar Viejo, Madrid, Spain, and Unidad de Tecnologia de Proteinas, Programa de Biotecnologia, Centro Nacional de Investigaciones Oncologicas (CNIO), Melchor FernAndez Almagro, 3, E-28229 Madrid, Spain.
Aplidin (plitidepsin) is an antitumoral agent that induces apoptosis via Rac1-JNK activation. A proteomic approach using 2D-DIGE technology found 52 cytosolic and 39 membrane proteins differentially expressed in wild-type and Aplidin-resistant HeLa cells, of which 39 and 27 were identified by MALDI-TOF mass spectrometry and database interrogation. A number of proteins involved in apoptosis pathways were found to be deregulated. Alterations in Rab geranylgeranyltransferase, protein disulfide isomerase (PDI), cystathionine gamma-lyase, ezrin, and cyclophilin A (CypA) were confirmed by immunoblotting. Moreover, the role of PDI and CypA in Aplidin resistance was functionally confirmed by using the inhibitor bacitracin and overexpression, respectively. These deregulated proteins are candidates to mediate, at least partially, Aplidin action and might provide a route to the cells to escape the induction of apoptosis by this drug. Keywords: Aplidin * differential proteomics * 2D-DIGE * chemoresistance * apoptosis pathways.