High-risk multiple myeloma predicted by circulating plasma cells and its genetic characteristics.

Introduction: Circulating plasma cells (CPC) have been reported to be one of the indicators of high-risk multiple myeloma (MM), yet the prognostic significance of CPC in Chinese population and the genetic mechanisms underlying CPC formation have not been fully elucidated. Methods: Patients with newly diagnosed MM were included in this study. We used multi-parameter flow cytometry (MFC) for CPC quantification and next-generation sequencing (NGS) technology for mutational landscape mapping to identify the correlation of CPC level with clinical characteristics and the mutations. Results: A total of 301 patients were enrolled in this investigation. We demonstrated that CPC quantification could effectively mirror the tumor load, and CPC ≥ 0.105% at diagnosis or detectable CPC after therapy indicates poor treatment response and adverse outcome, and the introduction of CPC into the R-ISS enables a more accurate risk stratification. Interestingly, we noticed an elevated percentage of light-chain MM in patients with higher CPC. Mutational landscape revealed that patients harboring mutations in TP53, BRAF, DNMT3A, TENT5C, and IL-6/JAK/STAT3 pathway-related genes tended to have higher CPC levels. Gene enrichment analysis demonstrated that pathways involving chromosome regulation and adhesion may be potential mechanisms accounting for CPC formation. Discussion: Accordingly, quantification of CPC may provide a less-invasive and reliable approach for identifying high-risk MM in Chinese population.

Identification of clinical implications and potential prognostic models of chromatin regulator mutations in multiple myeloma.

BACKGROUND: With the rapid development of next-generation sequencing (NGS) technologies, researchers are making efforts to reveal the genomic landscape of multiple myeloma (MM). However, the clinical significance of many mutations remains poorly defined due to the genetic heterogeneity of MM. To systematically explore the clinical implications of gene mutations and build practical prognostic models, we performed DNA sequencing in newly diagnosed MM patients. METHODS: MM cells were purified from bone marrow aspirates using CD138 microbeads and subjected to sequencing with a 387-gene Panel. Nomogram was developed using Cox's proportional hazards model, and candidate variables were screened by stepwise regression. Internal validation was carried out by the bootstrap method. RESULTS: Between July 2016 and December 2020, a total of 147 patients were included in our study. We found patients with a higher mutational load had a significantly shorter progress-free survival (PFS) (19.0 vs. 32.0 months, P = 0.0098) and overall survival (OS) (3-year OS rates were 66.1% and 80.0%, P = 0.0290). Mutations in chromatin regulators (CRs) including KMT2C (14.3%), KMT2D (14.3%), EP300 (11.6%) and ARID gene family (31.3%) were highly frequent in newly diagnosed MM patients. Interestingly, proteins encoded by these genes could form a complex called KMT2C/D COMPASS (KCDCOMs). Patients with mutations of ARID gene family had a significantly shorter PFS (15.5 vs. 34.0 months, P = 0.0003) and OS (3-year OS rates were 64.9% and 81.0%, P = 0.0351) than patients without ARID gene mutations. Incorporating ARID gene mutations into the current staging system could successfully improve their prognostic performance. The PFS and OS nomogram models (including 1q21 copies, ARID gene mutations, extramedullary disease, mutational load and TP53 mutations) showed good predicting performance in both training and validation sets. CONCLUSION: Our findings emphasized the importance of CRs mutations in newly diagnosed MM patients and indicated the mutations affecting KCDCOMs might promote the development of MM. High mutational load and harboring mutations in the ARID gene family were novel predictors of adverse prognosis in MM. Prognostic models based on gene mutations were commendably prognostic evaluation methods that could provide a reference for clinical practices.

Prognostic value of circulating clonal plasma cells in newly diagnosed multiple myeloma.

OBJECTIVES: Multiple myeloma (MM) involves a clinically and biologically heterogeneous malignancy of plasma cells. It is difficult to predict the prognosis of MM. The presence of circulating clonal plasma cells (CPC) has been associated with a worse prognosis in patients with MM. METHODS: This study retrospectively analysed CPC in 108 newly diagnosed MM patients by 8-colour flow cytometry to investigate their value for predicting the outcome and combined the level of CPC with the revised International Staging System (R-ISS) to stratify the MM patients according to risk. RESULTS: CPC were detected in 58/108 patients (53.7%). The optimum cut-off for the prediction of overall survival was determined to be 0.105%. Patients with higher R-ISS stages seemed to harbour more CPC. A level of CPC≥0.105% was an independent risk factor for adverse outcomes (P<0.001). The combination of the R-ISS staging system and level of CPC was used to stratify MM patients according to risk, and the combination of R-ISS stage III and a level of CPC≥0.105% defined the ultra-high-risk group. CONCLUSION: This study suggests that a high proportion of CPC is associated with aggressive disease and that the use of the current R-ISS system in conjunction with assessment of the level of CPC may facilitate the stratification of newly diagnosed MM patients into clinically relevant prognostic subgroups.

Clinical significance of CD200 expression in newly diagnosed multiple myeloma patients and dynamic changing during treatment.

The aim of our study was to determine the impact of CD200 expression in newly diagnosed myltiple myeloma (MM) patients. CD200+ patients had significantly shorter median overall survival time (OS) than CD200- patients (41.0 months vs. not reached, p = .009). The ratio of CD4+ to CD8+ T cells was lower in CD200+ patients and this reduction was significantly related to the increase of CD8+ T cells (p = .021). Moreover, we analyzed dynamic changes of CD200 expression in 47 CD200+ patients during treatment. Thirty-eight (80.9%) patients switched to CD200- during treatment. Those patients had a favorable survival compared with the others (median OS, 65.0 vs. 32.0 months, p < .001; median PFS, 29.0 vs. 11.5 months, p = .027). We concluded that CD200 expression is an independent marker for MM prognostic estimation during treatment.

[Detection of del(17p13) among newly diagnosed multiple myeloma cases using cytoplasmic light chain immunofluorescence combined with FISH and its clinical significance].

OBJECTIVE: To detect chromosomal aberrations by using cytoplasmic light chain immunofluorescence with fluorescence in situ hybridization (cIg-FISH), and to explore the correlation of del(17p13) with clinical characteristics, drug response and prognosis among patients with newly diagnosed multiple myeloma (NDMM). METHODS: Clinical data of 198 cases of NDMM was collected. cIg-FISH and a specific probe (TP53) were used to detect karyotypic abnormalities in bone marrow samples derived from the patients. Correlation between karyotypic abnormalities and clinical data was analyzed. RESULTS: Nineteen of the 198 patients (9.6%) were found to have a karyotype involving del(17p13). The overall survival (OS) and progression-free survival (PFS) for patients with or without del(17p13) was significantly different (P<0.01). No significant difference was found in OS and PFS between patients carrying a del(17p13) on bortezomib and non-bortezomib regimen (OS: P = 0.873; PFS: P = 0.610). CONCLUSION: cIg-FISH is a simple and convenient method for the detection of karyotypic anomalies in multiple myeloma. Del(17p13) is an indicator for poor prognosis for multiple myeloma patients. Bortezomib cannot improve the survival disadvantage of del(17p13).

Promoter hypermethylation influences the suppressive role of long non-coding RNA MEG3 in the development of multiple myeloma.

Methylation is a fundamental regulator of gene transcription. Long non-coding RNA maternally expressed 3 (MEG3) inhibits cell proliferation in various types of cancer. However, the molecular mechanisms of MEG3 methylation in the regulation of multiple myeloma (MM) are unknown. In the present study, MEG3 upregulation was negatively associated with the International Staging System (ISS) status of the bone marrow samples of 39 patients with MM. MEG3 overexpression in an MM cell line resulted in elevated p53 expression. Furthermore, the results of methylation-specific PCR revealed that the abnormal methylation status of the MEG3 promoter region was present in eight of the 39 bone marrow samples collected. Treatment of the MM cell line with the DNA methylation inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR) resulted in tumor cell proliferation inhibition, apoptosis induction and G0/G1 cell cycle arrest. Furthermore, 5-Aza-CdR decreased aberrant hypermethylation of the MEG3 promoter and increased the expression of MEG3. However, 5-Aza-CdR exerted no effect on p53 expression. To the best of our knowledge, the present study is the first to report that the demethylation reagent 5-Aza-CdR may serve as a therapeutic agent in MM by upregulating MEG3 expression. However, the mechanism of action was independent of p53 expression.

Low absolute CD4+ T cell counts in peripheral blood predict poor prognosis in patients with newly diagnosed multiple myeloma.

The T lymphocyte system plays an active role in tumor immunosurveillance in multiple myeloma (MM), and abnormal T lymphocyte populations are often observed in patients with MM. In the current study, we evaluated the prognostic impact of abnormal T lymphocyte subset distributions in patients with newly diagnosed MM (NDMM). Between December 2012 to October 2016, 110 NDMM patients were included in this study. Multiparameter flow cytometry was applied to quantitatively analysis the peripheral blood T lymphocyte subsets, including CD4+ T cell, CD8+ T cell, and CD4/CD8 ratio. Survival analyses were performed based on the patients' clinical data and the quantity of T lymphocyte subsets. The median follow-up time was 27.0 months (range, 2.5-66). Baseline percentages and absolute CD4+ T cell counts and the CD4/CD8 ratio were positively correlated with both overall survival (OS) and progression-free survival (PFS) according to Kaplan-Meier curves (p < .05). In the multivariate COX analysis, lower CD4+ T cell count was an independent unfavorable factor in predicting both OS (p = .016) and PFS (p = .010). Furthermore, lower CD4/CD8 ratio was an independent adverse prognostic factor for shorter PFS (p = .017). These results suggested that T lymphocyte subsets were crucial indicators in correlation with MM patients' prognosis. Low CD4+ T cell counts and CD4/CD8 ratio were independent unfavorable prognostic predictors for patients with MM at diagnosis.

[Correlation of Peripheral Blood T Lymphocyte Subsets with Prognosis of Elderly Patients with Newly Diagnosed Multiple Myeloma].

OBJECTIVE: To investigate the expression level of T lymphocyte subsets in elderly patients with newly diagnosed multiple myeloma (NDMM), and to evaluated the prognostic value of T lymphocytic abnormalities in elderly NDMM patients. METHODS: Pretreated peripheral blood of 39 newly diagnosed elder patients with MM was tested by multi-parameter flow cytometry (MFC) to quantitatively detect T lymphocyte subsets, including CD4+T cell, CD8+T cell, and CD4/CD8 ratio. The prognostic values T-lymphocyte subset were evaluated in newly diagnosed elderly patients with MM. RESULTS: The median follow-up time was 21.5 (range, 3.0-66.0) months. Absolute counts of CD4+T cell and CD4/CD8 ratio positively correlated with prognosis. In the multivariate COX analysis, lower CD4/CD8 ratio and CD4+T cell counts were identified to be independent adverse prognostic factors for OS. CONCLUSION: Lower CD4/CD8 ratio and CD4+T cell counts at initial diagnosis are independent unfavorable prognostic factors for elderly patients with MM, and T lymphocyte subsets are crucial indicators for MM patients' prognosis.

Long Non-Coding RNA MEG3 Functions as a Competing Endogenous RNA to Regulate HOXA11 Expression by Sponging miR-181a in Multiple Myeloma.

BACKGROUND/AIMS: Long non-coding RNA maternally expressed gene 3 (MEG3) has been reported to play an essential role in cancer progression and metastasis. However, the overall biological role and regulatory mechanism of MEG3 in multiple myeloma (MM) development and progression remains largely ill-defined. METHODS: MEG3 and miR-181a expression of MM patients were analyzed by publicly available MM data sets. Cell counting kit-8 and flow cytometry analysis were used to identify the function of MEG3 on MM in vitro. Additionally, we conducted tumor formation experiments in mice models to explain the role of MEG3 on MM in vivo. Then, several mechanism experiments, including dual-luciferase reporter assay and RNA immunoprecipitation were performed to evaluate the emulative relationship between MEG3 and miR-181a. RESULTS: In this research, we found that MEG3 was downregulated in MM patients, which was linked with tumor progression. In addition, we demonstrated that miR-181a was overexpressed in MM patients in consistent with its cancer-promoting function. Importantly, several mechanism experiments revealed that MEG3, acting as an endogenous competitive RNA, could contend with miR-181a to inhibit tumor progression. Furthermore, as the target mRNA of miR-181a, homeobox gene A11(HOXA11) could be positively regulated by MEG3 through sponging miR-181a competitively in vitro. CONCLUSION: Our present work supplies the first discovery of a MEG3/miR-181a/HOXA11 regulatory network in MM and highlights that MEG3 may serve as a promising target for MM therapy in the future.

Cereblon: A Protein Crucial to the Multiple Functions of Immunomodulatory Drugs as well as Cell Metabolism and Disease Generation.

It is well known that cereblon is a key protein in autosomal recessive nonsyndromic mental retardation. Studies have reported that it has an intermediary role in helping immunomodulatory drugs perform their immunomodulatory and tumoricidal effects. In addition, cereblon also regulates the expression, assembly, and activities of other special proteins related to cell proliferation and metabolism, resulting in the occurrence and development of metabolic diseases. This review details the multiple functions of cereblon and the underlying mechanisms. We also put forward some unsolved problems, including the intrinsic mechanism of cereblon function and the possible regulatory mechanisms of its expression.

High serum lactate dehydrogenase predicts an unfavorable outcome in Chinese elderly patients with multiple myeloma.

There is significant heterogeneity among multiple myeloma (MM) patients with the survival duration varying greatly from a few months to several years. This study retrospectively analyzed serum lactate dehydrogenase (LDH) in 105 cases of newly diagnosed elderly MM patients to investigate its value for outcome prediction. Serum LDH concentrations were evaluated prior to induction therapy. Prognostic analyses were carried out based on LDH levels and patients' other clinical data. We also applied the recently proposed Revised International Staging System (R-ISS) to 70 patients with the available data. Of all the patients, elevated serum LDH levels (≥271U/L) were observed in 13.3% (14 out of 105) patients at diagnosis. Compared with normal LDH group, high LDH group had significantly shorter overall survival (OS) (15.5 vs. 52.5 months, p = 0.002) and median progression free survival (PFS) (12.0 vs. 24 months, p = 0.030), as well as 2-year OS rate (20% vs. 81%, p < 0.001) and PFS rate (22% vs. 44%, p = 0.005). A multivariate analysis identified high LDH as a unique independent adverse prognostic parameter for both OS and PFS. In addition, there were significant differences between R-ISS II and R-ISS III patients in both median OS (52.5 vs. 15.5 months, p < 0.001) and PFS (23 vs. 7.5 months, p = 0.004). Furthermore, high LDH was a unique independent adverse indicator for overall response rate (ORR) and early death in elderly MM patients. These results identified LDH as an unfavorable prediction for the outcome of Chinese elderly patients with MM. R-ISS based on LDH is superior to ISS in prognostic assessment.