The expression of 16 genes related to the cell of origin and immune response predicts survival in elderly patients with diffuse large B-cell lymphoma treated with CHOP and rituximab

Gene expression profiles have been associated with clinical outcome in patients with diffuse large B-cell lymphoma (DLBCL) treated with anthracycline-containing chemotherapy. Using Affymetrix HU133A microarrays, we analyzed the lymphoma transcriptional profile of 30 patients treated with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) and 23 patients treated with rituximab (R)-CHOP in the Groupe d'Etude des Lymphomes de l'Adulte clinical centers. We used this data set to select transcripts showing an association with progression-free survival in all patients or showing a differential effect in the two treatment groups. We performed real-time quantitative reverse transcription-PCR in the 23 R-CHOP samples of the screening set and an additional 44 R-CHOP samples set to evaluate the prognostic significance of these transcripts. In these 67 patients, the level of expression of 16 genes and the cell-of-origin classification were significantly associated with overall survival, independently of the International Prognostic Index. A multivariate model comprising four genes of the cell-of-origin signature (LMO2, MME, LPP and FOXP1) and two genes related to immune response, identified for their differential effects in R-CHOP patients (APOBEC3G and RAB33A), demonstrated a high predictive efficiency in this set of patients, suggesting that both features affect outcome in DLBCL patients receiving immunochemotherapy.