Identification of proteomic signatures of mantle cell lymphoma, small lymphocytic lymphoma, and marginal zone lymphoma biopsies by surface enhanced laser desorption/ionization-time of flight mass spectrometry.

Mantle cell lymphoma (MCL), small lymphocytic lymphoma (SLL), and marginal zone lymphoma (MZL) are small B-cell non-Hodgkin lymphomas (NHLs) that may be difficult to distinguish. In order to identify specific proteomic biomarkers, differential proteomic analysis of these three NHLs was performed using surface enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF-MS). Whole cell lysates obtained from 18 MCL, 20 SLL, and 20 MZL biopsies were applied on two different ProteinChips (cationic and anionic). Hierarchical clustering and discriminating scores combined with an innovative bio-informatics microdissection strategy allowed us to distinguish specific lymphoma proteomic signatures based on the expression of 37 protein peaks. SELDI-assisted protein purification combined with nano-liquid chromatography (LC) quadrupole-time of flight tandem mass spectrometry (Q-TOF MS/MS) was used to identify proteins overexpressed in both MCL and SLL tumors. Among them two histones, H2B and H4, were identified in MCL tumor biopsies and the signal recognition particle 9 kDa protein, SRP9, in SLL tumor biopsies.