Expression data from CD138+ cells obtained from MM patients at diagnosis

Thalidomide-dexamethasone (TD) combination is an effective induction therapy for newly diagnosed multiple myeloma patients, candidates for subsequent autologous stem cell transplantation (ASCT). Since maximization of tumor response before ASCT may favorably affect the clinical outcomes, we designed a study to identify a gene expression profile (GEP) signature predictive of attainment of complete response to TD induction therapy. CD138+ bone marrow samples obtained at diagnosis from 112/311 patients were analyzed. Two subsequent time phases were planned. Firstly, a GEP supervised analysis, performed on a training set of 32 patients, allowed to identify 157 probe sets differentially expressed in complete responder + near complete responder (CR+nCR) versus partial responder patients. Than, we generated an 8-gene GEP signature predicting at diagnosis the probability to achieve CR+nCR to TD induction therapy. The performance of this assay was subsequently validated in an 80 patients training set. The 8-gene signature provide a negative predictive value of 93% and a positive predictive value of 44%. The 8 genes were down-regulated in patients who achieved at least a nCR. These results could be an important first step to adopting a diagnostic assay, used to determine, at diagnosis, patients who will respond more favourably to a particular treatment strategy.

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Terragna C, Renzulli M, Remondini D, Tagliafico E, Di Raimondo F, Patriarca F, Martinelli G, Roncaglia E, Masini L, Tosi P, Zamagni E, Tacchetti P, Ledda A, Brioli A, Angelucci E, Testoni N, Marzocchi G, Galieni P, Gozzetti A, Martello M, Dico F, Mancuso K, Cavo M