Elena Vladimirovna Dementyeva

Circulating serum microRNAs as novel diagnostic and prognostic biomarkers for multiple myeloma and monoclonal gammopathy of undetermined significance

Multiple myeloma still remains incurable in the majority of cases prompting a further search for new and better prognostic markers. Emerging evidence has suggested that circulating microRNAs can serve as minimally invasive biomarkers for multiple myeloma and monoclonal gammopathy of undetermined significance. In this study, a global analysis of serum microRNAs by TaqMan Low Density Arrays was performed, followed by quantitative real-time PCR. The analyses revealed five deregulated microRNAs: miR-744, miR-130a, miR-34a, let-7d and let-7e in monoclonal gammopathy of undetermined significance, newly diagnosed and relapsed multiple myeloma when compared to healthy donors. Multivariate logistical regression analysis showed that a combination of miR-34a and let-7e can distinguish multiple myeloma from healthy donors with a sensitivity of 80.6% and a specificity of 86.7%, and monoclonal gammopathy of undetermined significance from healthy donors with a sensitivity of 91.1% and a specificity of 96.7%. Furthermore, lower levels of miR-744 and let-7e were associated with shorter overall survival and remission of myeloma patients. One-year mortality rates for miR-744 and let-7e were 41.9% and 34.6% for the ‘low’ expression and 3.3% and 3.9% for the ‘high’ expression groups, respectively. Median time of remission for both miR-744 and let-7e was approximately 11 months for the ‘low’ expression and approximately 47 months for the ‘high’ expression groups of myeloma patients These data demonstrate that expression patterns of circulating microRNAs are altered in multiple myeloma and monoclonal gammopathy of undetermined significance and miR-744 with let-7e are associated with survival of myeloma patients.

Clinical implication of centrosome amplification and expression of centrosomal functional genes in multiple myeloma.

BackgroundMultiple myeloma (MM) is a low proliferative tumor of postgerminal center plasma cell (PC). Centrosome amplification (CA) is supposed to be one of the mechanisms leading to chromosomal instability. Also, CA is associated with deregulation of cell cycle, mitosis, DNA repair and proliferation. The aim of our study was to evaluate the prognostic significance and possible role of CA in pathogenesis and analysis of mitotic genes as mitotic disruption markers.Design and methodsA total of 173 patients were evaluated for this study. CD138+ cells were separated by MACS. Immunofluorescent labeling of centrin was used for evaluation of centrosome amplification in PCs. Interphase FISH with cytoplasmic immunoglobulin light chain staining (cIg FISH) and qRT-PCR were performed on PCs.ResultsBased on the immunofluorescent staining results, all patients were divided into two groups: CA positive (38.2%) and CA negative (61.8%). Among the newly diagnosed patients, worse overall survival was indicated in the CA negative group (44/74) in comparison to the CA positive group (30/74) (P = 0.019).Gene expression was significantly down-regulated in the CA positive group in comparison to CA negative in the following genes: AURKB, PLK4, TUBG1 (P < 0.05). Gene expression was significantly down-regulated in newly diagnosed in comparison to relapsed patients in the following genes: AURKA, AURKB, CCNB1, CCNB2, CETN2, HMMR, PLK4, PCNT, and TACC3 (P < 0.05).ConclusionsOur findings indicate better prognosis for CA positive newly diagnosed patients. Considering revealed clinical and gene expression heterogeneity between CA negative and CA positive patients, there is a possibility to characterize centrosome amplification as a notable event in multiple myeloma pathogenesis.

Bone marrow plasma cell separation - validation of separation algorithm

Monoclonal gammopathy is characterized by the presence of monoclonal immunoglobulin which is produced by a specifi c clone of terminally differentiated long-living plasma cells (PC) in the bone marrow. More detailed understanding of this clone at the genomic and proteomic level as well as its comparison with the population of normal PC is possible only after the clone is separated from other BM cells.

Molecular heterogeneity and centrosome-associated genes in multiple myeloma.

Abstract In multiple myeloma (MM), biologic complexity originates from complex oncogenic processes involving somatic acquisition of myriad mutations coupled with genetic variability within the host. This pathogenically determined molecular heterogeneity predetermines clinical intricacy. In this study, we performed gene expression profiling (GEP) focusing on centrosome-related genes to determine the molecular heterogeneity for centrosome-associated genes in patients with MM. We identified the gene pattern with an impact on myeloma pathogenesis. According to expression tendency, three subgroups of patients were established. The revealed molecular signature is related to overall survival as well as to clinical parameters and the International Staging System. Associations with integral clinical parameters allow us to proclaim the impact of the revealed functional gene set in MM genesis. We believe that future investigation of this molecular heterogeneity will help to refine the broad prognoses offered by present-day established systems and even sub-stratify them.

Association of aneuploidy category with centrosome amplification in multiple myeloma

Multiple myeloma is a lymphoproliferative disease characterized by clonal expansion of neoplastic plasma cells (PCs) within the bone marrow. Although PCs are recognized as fully malignant cells, the exact developmental stage at which malignant transformation occurs is still unknown. Since centrosome abnormalities constitute one of the most important mechanisms implicated in chromosomal instability in cancer, the aim of this study was to investigate a possible association of centrosome amplification in populations of B-cell lineage with specific chromosome aberrations and aneuploidy categories occurring in MM. For this purpose, a total of 140 patients with MM were included in the study. In our study, we showed a correlation between centrosome amplification in B cells and hyperdiploidy in plasma cells. This raises the suspicion of a possible impact of abnormal B cells in myeloma cell development.