Aberrant plasma cells clonal composition in immunoglobulin light chain amyloidosis

Immunoglobulin light chain amyloidosis (AL amyloidosis) is a haematological disorder characterized by production of extra-cellular insoluble protein fibrils forming amyloid deposits that accumulate in various tissues and organs. AL amyloidosis develops, similarly as multiple myeloma (MM), from precancerous stage, monoclonal gammopathy of undetermined significance (MGUS). AL amyloidosis may coexist with other plasma cell dyscrasias, like MM. Genetic background determining MGUS to AL amyloidosis transition, as well as clonal architecture of combined AL amyloidosis and MM diseases has not been elucidated yet. We employ exome sequencing on FACS sorted population of aberrant plasma cells from all disease forms, MGUS, AL amyloidosis and combined AL amyloidosis and MM, to reveal i) the mutational profile typical for ALA and ii) to identify cancer drivers that distinguish precancerous MGUS from fatal ALA and iii) to trace the clonal evolution of AL amyloidosis combined with MM.

Genomic analysis of residual clone in multiple myeloma: approach for targeted therapy

Multiple myeloma (MM) is a plasma cell dyscrasia causing damage of multiple organs with fatal consequences for patients.  Despite the success of modern therapies eliminating a vast bulk of the aberrant cells, surviving residual clones eventually lead to the relapse of the disease. Accumulation of genomic alterations during the stage of minimal residual disease (MRD) likely contributes to a selective grow advantage and survival under the drug pressure. Identification of specific mutations in MM patients with MRD can provide unique opportunities to target the residual plasma cell clones. We aim to identify mutations and deregulated gene expression in residual aberrant plasma cell population and to pinpoint molecular targets for precision medicine. To overcome the inevitable problem of very limited availability of study material, aberrant plasma cells, that complicates the large-scale mutation screening study, we use whole genome amplification technique followed by next-generation exome sequencing and customized bioinformatic pipeline.



Molecular mechanisms of drug resistance and metastasis development in multiple myeloma

Multiple myeloma (MM) is yet uncurable malignancy of the terminally differentiated plasma cells. Formation of metastasis and development of drug resistance belong to the main pathogenic mechanisms with limited therapeutical options. In order to better understand these processes on molecular and cellular level, we use bottom up and hypothesis-driven approaches based on deep genomic and transcriptiomic analysis of MM patient samples. Recently, we have identified several genetic and transcriptomic changes in malignant plasma cells that are directly linked to resistance to the most commonly used drugs (proteasomal inhibitors and immunomodulatory agents) in the treatment of MM. Further, we have found genes that seem to be involved in modulation of MM cells ability to migrate out of the supportive bone marrow environment and home in other tissues. To study the resposible molecular processes we use state-of-the art equipment and approaches inlcuding proteomic, biochemical, genetic, functional cell-based and in vivo (mouse models and patient derived cells) analysis. Particularly, we focus on a complex enzymatic network involved in ubiquitin-proteasome system, regulation of oxidative stress and actin cytoskeleton. The main goal of our research is to identify novel disease biomarkers, evaluate putative drug targets, and unveil yet undescribed, fundamental biological processes.

Study of oncogenic MyD88 signalling for discovery of new therapeutic targets in Waldenstom macroglobulinema and Diffuse large B cell Lymphoma

The key adaptor protein of innate immunity MyD88 and IRAK kinases orchestrate cell signalling of IL-1β, IL-18, and most toll like receptors (TLRs). Pathological mutations in MyD88 transform B cells into Waldenstrom macroglobulinemia and aggressive forms of lymphoma (ABC DLBCL) by mimicking receptor stimulation and activating prosurvival signaling pathways. However, the composition of aberrant MyD88 signalling complexes and underlying molecular processes remain unresolved. Using proteomic, genetic, and functional approaches, we interrogate the assembly and composition of MyD88 protein complexes and determine requirement for E3 ubiquitin ligases and deubiquitinases and their interplay with IRAKs and other kinases. Specifically, we probe the noncatalytic scaffolding function of IRAK1 kinase and its regulation by ubiquitination. Ultimately, we aim to identify new targets for development of potent and specific modulators for combined and stand-alone immune therapy in lymphoma and other MyD88 dependent diseases.



Development of novel cell based therapies

In this project we are studying the potential of Natural Killers (NK) for cancer immunotherapy. So far T cells have been the mainstay of cancer immunotherapy; however, it is generally recognized that NK cells also play an essential role in antitumor immunity. NK cells were certainly recognized as main immune effector cells in the prevention of metastases through the elimination of circulating cancer stem cells with a high metastatic potential. Moreover, as solid tumors have a propensity to particularly down-regulate MHC-I, NK cells provide a failsafe mechanism in these circumstances where cytotoxic T cells, which depend on MHC-I for tumor recognition and elimination, are debilitated. Besides, allogenic NK are well tolerated without Graft-versus-host disease.