Expression and significance of miR-21 in multiple myeloma patients.

The aim of the present study is to examine the expression level of peripheral mir-21 in multiple myeloma (MM) patients and to determine its clinical significance. MM patients (30), monoclonal gammopathy of undetermined significance (MGUS) patients (14), and normal controls (20) were recruited to determine the serum level of ß2-MG, IgA and IgM, IgG, λ, κ, TP, ALB, Hb, LDH, and Ca(2+). Gene expression of mir-21 was quantified by SYBR green real-time fluorescent quantitative PCR. We found that the expression level of serum mir-21 in the MM group was significantly higher than the MGUS group and the NC group (P < 0.01). According to the ISS installment, the level of mir-21, lgG, κ, and ALB in the MM group in stage I differed from that in stages II and III. The level of IgA, ß2-MG in stage III was higher as compared with stage I and II (P < 0.05 and P < 0.01).The levels of mir-21, κ, (κ+λ), IgG, (IgG + IgA + IgM), and ß2-MG in MM patients were positively correlated with ALB (P < 0.01). Based on the results, miR-21 plays an important role as an oncogene. Mir-21 may be important in the occurrence, development, and disease prognosis of MM.

Pathway-based network analysis of myeloma tumors: monoclonal gammopathy of unknown significance, smoldering multiple myeloma, and multiple myeloma.

Although many studies have been carried out on monoclonal gammopathy of unknown significances (MGUS), smoldering multiple myeloma (SMM), and multiple myeloma (MM), their classification and underlying pathogenesis are far from elucidated. To discover the relationships among MGUS, SMM, and MM at the transcriptome level, differentially expressed genes in MGUS, SMM, and MM were identified by the rank product method, and then co-expression networks were constructed by integrating the data. Finally, a pathway-network was constructed based on Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, and the relationships between the pathways were identified. The results indicated that there were 55, 78, and 138 pathways involved in the myeloma tumor developmental stages of MGUS, SMM, and MM, respectively. The biological processes identified therein were found to have a close relationship with the immune system. Processes and pathways related to the abnormal activity of DNA and RNA were also present in SMM and MM. Six common pathways were found in the whole process of myeloma tumor development. Nine pathways were shown to participate in the progression of MGUS to SMM, and prostate cancer was the sole pathway that was involved only in MGUS and MM. Pathway-network analysis might provide a new indicator for the developmental stage diagnosis of myeloma tumors.

Differential Expression of Non-Shelterin Genes Associated with High Telomerase Levels and Telomere Shortening in Plasma Cell Disorders.

Telomerase, shelterin proteins and various interacting factors, named non-shelterin proteins, are involved in the regulation of telomere length (TL). Altered expression of any of these telomere-associated genes can lead to telomere dysfunction, causing genomic instability and disease development. In this study, we investigated the expression profile of a set of non-shelterin genes involved in essential processes such as replication (RPA1), DNA damage repair pathways (MRE11-RAD50-NBS1) and stabilization of telomerase complex (DKC1), in 35 patients with monoclonal gammopathy of undetermined significance (MGUS) and 40 cases with multiple myeloma (MM). Results were correlated with hTERT expression, TL and clinical parameters. Overall, a significant increase in DKC1, RAD50, MRE11, NBS1 and RPA1 expression along with an upregulation of hTERT in MM compared with MGUS was observed (p≤0.032). Interestingly, in both entities high mRNA levels of non-shelterin genes were associated with short TLs and increased hTERT expression. Significant differences were observed for DKC1 in MM (p ≤0.026), suggesting an important role for this gene in the maintenance of short telomeres by telomerase in myeloma plasma cells. With regard to clinical associations, we observed a significant increase in DKC1, RAD50, MRE11 and RPA1 expression in MM cases with high bone marrow infiltration (p≤0.03) and a tendency towards cases with advanced ISS stage, providing the first evidence of non-shelterin genes associated to risk factors in MM. Taken together, our findings bring new insights into the intricate mechanisms by which telomere-associated proteins collaborate in the maintenance of plasma cells immortalization and suggest a role for the upregulation of these genes in the progression of the disease.

Biochemical abnormalities in multiple myeloma

Monoclonial gammopathies can either be benign or more commonly malignant. The commonest disease associated with it is multiple myeloma. Over the seven-year period 1984-1990, two hundred and thirty-four monoclonal gammopathies were seen at the University Hospital, Jamaica. Multiple myeloma was diagnosed in one hundred and fifty-six cases (84 males and 72 females). The diagnosis of most of the others were not known as the samples came from other institution. Of the patients with myeloma, the most common immunoglobulin type was IgG followed by IgA and then pure light chain disease. Only in about half of the cases where urine was analysed was Bence-Jones protien found. The majority of the cases had abnormal total serum protein, albumin and total globulin concentrations. Most of the cases also were in renal failure. Hypercalcaemia, hyperphoshataemia, elevated alkaline phosphate, gammaglutamyl transferase and aspartate aminotransferase occured in about one-third of them. These results were not much different from those reported in other countries

Biochemical abnormalities in multiple myeloma

Monoclonial gammopathies can either be benign or more commonly malignant. The commonest disease associated with it is multiple myeloma. Over the seven-year period 1984-1990, two hundred and thirty-four monoclonal gammopathies were seen at the University Hospital, Jamaica. Multiple myeloma was diagnosed in one hundred and fifty-six cases (84 males and 72 females). The diagnosis of most of the others were not known as the samples came from other institution. Of the patients with myeloma, the most common immunoglobulin type was IgG followed by IgA and then pure light chain disease. Only in about half of the cases where urine was analysed was Bence-Jones protien found. The majority of the cases had abnormal total serum protein, albumin and total globulin concentrations. Most of the cases also were in renal failure. Hypercalcaemia, hyperphoshataemia, elevated alkaline phosphate, gammaglutamyl transferase and aspartate aminotransferase occured in about one-third of them. These results were not much different from those reported in other countries. (AU)