The genetic and genomic background of multiple myeloma patients achieving complete response after induction therapy with bortezomib, thalidomide and dexamethasone (VTD).

// Carolina Terragna 1 , Daniel Remondini 2 , Marina Martello 1 , Elena Zamagni 1 , Lucia Pantani 1 , Francesca Patriarca 3 , Annalisa Pezzi 1 , Giuseppe Levi 2 , Massimo Offidani 4 , Ilaria Proserpio 5 , Giovanni De Sabbata 6 , Paola Tacchetti 1 , Clotilde Cangialosi 7 , Fabrizio Ciambelli 8 , Clara Virginia Vigano 9 , Flores Angela Dico 1 , Barbara Santacroce 1 , Enrica Borsi 1 , Annamaria Brioli 1 , Giulia Marzocchi 1 , Gastone Castellani 2 , Giovanni Martinelli 1 , Antonio Palumbo 10 , Michele Cavo 1 1 ”Seragnoli” Institute of Hematology, Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Bologna University School of Medicine, Bologna, Italy 2 Department of Physics and Astronomy (DIFA), Bologna University, Bologna, Italy 3 Clinica Ematologica, DISM, University of Udine, Udine, Italy 4 Clinica di Ematologia, A.O.U. Ospedali Riuniti di Ancona, Ancona, Italy 5 U.O Oncologia Medica, Ospedale di Circolo e Fondazione Macchi, Varese, Italy 6 Ematologia Clinica, A.O.U. Ospedali Riuniti, Trieste, Italy 7 Hematology Division UTMO, Azienda “Ospedali Riuniti Villa Sofia-Cervello” Presidio Ospedaliero V.Cervello, Palermo, Italy 8 S.C.Oncologia Medica, A.O. Sant’Antonio Abate, Gallarate, Varese, Italy 9 Unita Operativa di Ematologia, Istituti Ospitalieri di Cremona, Cremona, Italy 10 Myeloma Unit, Division of Hematology, University of Torino, A.O.U. Citta della Salute e della Scienza di Torino, Torino, Italy Correspondence to: Michele Cavo, e-mail: michele.cavo@unibo.it Keywords: multiple myeloma, gene expression profile, SNPs, VTD, complete response Received: August 06, 2015      Accepted: September 16, 2015      Published: November 09, 2015 ABSTRACT The prime focus of the current therapeutic strategy for Multiple Myeloma (MM) is to obtain an early and deep tumour burden reduction, up to the level of complete response (CR). To date, no description of the characteristics of the plasma cells (PC) prone to achieve CR has been reported. This study aimed at the molecular characterization of PC obtained at baseline from MM patients in CR after bortezomib-thalidomide-dexamethasone (VTD) first line therapy. One hundred and eighteen MM primary tumours obtained from homogeneously treated patients were profiled both for gene expression and for single nucleotide polymorphism genotype. Genomic results were used to obtain a predictor of sensitivity to VTD induction therapy, as well as to describe both the transcription and the genomic profile of PC derived from MM with subsequent optimal response to primary induction therapy. By analysing the gene profiles of CR patients, we identified a 5-gene signature predicting CR with an overall median accuracy of 75% (range: 72%–85%). In addition, we highlighted the differential expression of a series of genes, whose deregulation might explain patients’ sensitivity to VTD therapy. We also showed that a small copy number loss, covering 606Kb on chromosome 1p22.1 was the most significantly associated with CR patients.