Circulating plasma cells as a predictive biomarker in Multiple myeloma: an updated systematic review and meta-analysis.

BACKGROUND: Circulating plasma cells (CPCs) are defined by the presence of peripheral blood clonal plasma cells, which would contribute to the progression and dissemination of multiple myeloma (MM). An increasing number of studies have demonstrated the predictive potential of CPCs in the past few years. Therefore, there is a growing need for an updated meta-analysis to identify the specific relationship between CPCs and the prognosis of MM based on the current research status. METHODS: The PubMed, Embase, and Cochrane Library databases were screened to determine eligible studies from inception to November 5, 2023. Publications that reported the prognostic value of CPCs in MM patients were included. Hazard ratios (HRs) with 95% confidence intervals (CIs) of overall survival (OS) and progression-free survival (PFS) were extracted to pool the results. Subgroup analyses were performed based on region, sample size, cut-off value, detection time, initial treatment, and data type. The association between CPCs level and clinicopathological characteristics, including the International Staging System (ISS), Revised-ISS (R-ISS), and cytogenetic abnormalities were also evaluated. Statistical analyses were conducted using STATA 17.0 software. RESULTS: Twenty-two studies with a total of 5637 myeloma patients were enrolled in the current meta-analysis. The results indicated that myeloma patients with elevated CPCs were expected to have a poor OS (HR = 2.19, 95% CI: 1.81-2.66, p < 0.001) and PFS (HR = 2.45, 95% CI: 1.93-3.12, p < 0.001). Subgroup analyses did not alter the prognostic role of CPCs, regardless of region, sample size, cut-off value, detection time, initial treatment, or data type. Moreover, the increased CPCs were significantly related to advanced tumour stage (ISS III vs. ISS I-II: pooled OR = 2.89, 95% CI: 2.41-3.46, p < 0.001; R-ISS III vs. R-ISS I-II: pooled OR = 3.65, 95% CI: 2.43-5.50, p < 0.001) and high-risk cytogenetics (high-risk vs. standard-risk: OR = 2.22, 95% CI: 1.60-3.08, p < 0.001). CONCLUSION: Our meta-analysis confirmed that the increased number of CPCs had a negative impact on the PFS and OS of MM patients. Therefore, CPCs could be a promising prognostic biomarker that helps with risk stratification and disease monitoring.

There is a growing need for an updated meta-analysis to identify the specific relationship between CPCs and the prognosis of MM based on the current research status.Our meta-analysis revealed that a high CPCs level was significantly associated with worse OS and PFS in MM patients.CPCs could be a promising predictive biomarker that helps with risk stratification and disease monitoring.

Development of a nomogram prognostic model for early Grade ≥ 3 infection in newly diagnosed multiple myeloma based on immunoparesis.

BACKGROUND: Infection, a significant cause of death in multiple myeloma (MM) patients, is a common complication and is closely associated with immunoparesis. There exists no clear definition of early infection, so early infection is defined in this paper as the occurrence within 3 months after diagnosis, considering the high incidence of infections within 3 months after diagnosis. This study established a new nomogram model based on immunoparesis to identify MM patients with high-risk early infection. METHODS: A retrospective collection of 430 NDMM patients from June 2013 to June 2022 was conducted, and the patients were further divided into a training cohort and a validation cohort. In the training cohort, the least absolute shrinkage and selection operator (LASSO) was used to select the best variables that can be used to establish a new nomogram prediction model. Validation was performed in the validation and entire cohorts. RESULTS: After diagnosis, 67.7 % of the patients suffered from severe infection within 1 year, and 59.5 % experienced the first severe infection within 3 months. Variables associated with an increased risk of severe infection in the first 3 months included: BMPC, D-dimer, serum ß2 microglobulin, immunoparesis, albumin, and eGFR. The nomogram based on the above six factors achieved a good C-index of 0.754, 0.73, and 0.731 in predicting early infection in the training cohort, validation cohort, and entire cohort, respectively. Finally, the time-dependent receiver operating characteristic (ROC) curve and decision curve analysis (DCA) of the nomogram showed that the model provided superior diagnostic capacity and clinical net benefit. CONCLUSION: In this study, we established a nomogram model to predict early grade ≥ 3 infection in NDMM patients. This model can assist clinicians in identifying NDMM patients with high-risk infections and improve their prognosis through early intervention.

Hematologists' awareness of venous thromboembolism in multiple myeloma: a national survey in China.

BACKGROUND: Venous thromboembolism (VTE) is one of the most common and severe complications of multiple myeloma (MM). The aim of this study was to learn about the current awareness regarding MM-associated VTE among Chinese hematologists. METHODS: A nationwide, online, questionnaire-based survey was sent to the specialized hematologists in mainland China. The questionnaire investigated respondents' demographic and occupational characteristics, their ability to identify VTE risk factors, and their thromboprophylaxis decisions for different anti-MM regimens. Six clinical vignettes were used to evaluate hematologists' awareness of stratified thromboprophylaxis. The data were analyzed using SPSS software. RESULTS: A total of 518 valid questionnaires were received. Of the 518 hematologists investigated, only 23.7% of them could identify VTE-related risk factors correctly. Most hematologists could select appropriate thromboprophylaxis for common anti-MM regimens such as VCd (bortezomib, cyclophosphamide, and dexamethasone) and VRd (bortezomib, lenalidomide, and dexamethasone), but not for uncommon ones such as VTD-PACE (bortezomib, thalidomide, dexamethasone, cisplatin, doxorubicin, cyclophosphamide, and etoposide) and KRd (carfilzomib, lenalidomide, and dexamethasone). The results from the vignettes suggested that only 19.5% of the hematologists could be defined as the 'stratified thromboprophylaxis' group, and the awareness of stratified thromboprophylaxis depended significantly on physicians' age and working seniority. CONCLUSION: The results of our study showed that a large proportion of Chinese hematologists failed to recognize the VTE risk factors, most of them cannot select appropriate thromboprophylaxis for different MM therapeutic regimens and lack awareness of stratified thromboprophylaxis for MM-associated VTE. A standard VTE prevention guideline is urgently needed for the Chinese myeloma group. Continuous education for new professionals should be encouraged. A VTE collaborative group is supposed to be established in each hospital to enhance the overall medical care for VTE patients.

The substantial myeloma patient population and extensive use of immunomodulatory drugs indicate that MM-associated VTE deserves more attention in China.The results from our cross-sectional study showed that a significant proportion of Chinese hematologists failed to identify the VTE risk factors, most of them cannot select appropriate thromboprophylaxis for different MM therapeutic regimens and lack awareness of stratified thromboprophylaxis for MM-associated VTE.

MALAT1 regulates network of microRNA-15a/16-VEGFA to promote tumorigenesis and angiogenesis in multiple myeloma.

MALAT1 is one of the most hopeful members implicated in angiogenesis in a variety of non-malignant diseases. In multiple myeloma (MM), MALAT1 is recognized as the most highly expressed long non-coding RNA. However, the functional roles of MALAT1 in angiogenesis and the responsible mechanisms have not yet been explored. Herein, we discovered a novel regulatory network dependent on MALAT1 in relation to MM tumorigenesis and angiogenesis. We observed that MALAT1 was upregulated in MM and significantly associated with poor overall survival. MALAT1 knockdown suppressed MM cell proliferation and promoted apoptosis, while restricting endothelial cells angiogenesis. Moreover, MALAT1 directly targeted microRNA-15a/16, and microRNA-15a/16 suppression partly reverted the effects of MALAT1 deletion on MM cells in vitro as well as tumor growth and angiogenesis in vivo. In addition, further study indicated that MALAT1 functioned as a competing endogenous RNA for microRNA-15a/16 to regulate vascular endothelial growth factor A (VEGFA) expression. Our results suggest that MALAT1 plays an important role in the regulatory axis of microRNA-15a/16-VEGFA to promote tumorigenicity and angiogenesis in MM. Consequently, MALAT1 could serve as a novel promising biomarker and a potential antiangiogenic target against MM.

[Retracted] siRNA­mediated inhibition of endogenous brain­derived neurotrophic factor gene modulates the biological behavior of HeLa cells.

Subsequently to the publication of the above article and a Corrigendum that was published to indicate corrections made to Fig. 7 (DOI: 10.3892/or.2021.7922; published online on January 5, 2021), a concerned reader drew the Editor's attention to the fact that, comparing between a pair of panels in the Figure, there was an overlapping section of data; moreover, this overlapping section contained apparent anomalies that could not be easily accounted for through a straightforward re­use of one of the data panels. The authors conceded that there was partial duplication between the images shown in Fig. 7B and F, although they were unable to access the related raw data as the experiments had been performed almost 10 years ago. Secondly, the authors informed the Editor that the corresponding author did not know he was on the author list at the time of submission. Although the authors' were granted permission to publish the Corrigendum, the Editor now considers that the paper should be retracted on account of the uncertainties in the presented revised data and the authors' admission concerning the corresponding author. Therefore, this paper has been retracted from the Journal. The authors are in agreement with the decision to retract the article. The Editor apologizes for any inconvenience caused. [Oncology Reports 37: 2751­2760, 2017; DOI: 10.3892/or.2017.5569].

Ferroptosis in hematological malignancies and its potential network with abnormal tumor metabolism.

Ferroptosis, a new type of regulated cell death, displays characteristics that transparently differ from apoptosis, autophagy and necroptosis. There is growing appreciation that targeting ferroptosis is potentially a novel strategy in anti-tumor therapy, especially for invasive malignancies demonstrating resistance to chemotherapy. Almost all types of cancer cells depend on abnormal metabolic activities to participate in vicious progression, giving the possibility to interfere with underlying metabolic preferences and compromise malignant cells by inducing ferroptosis. In this perspective, we give an overview of potential interactions between ferroptosis and abnormal tumor metabolism, with special focus on systematic researches in hematological malignancies.

FTO promotes multiple myeloma progression by posttranscriptional activation of HSF1 in an m6A-YTHDF2-dependent manner.

N6-methyladenosine (m6A), as the most pervasive internal modification of eukaryotic mRNA, plays a crucial role in various cancers, but its role in multiple myeloma (MM) pathogenesis has not yet been investigated. In this study, we revealed significantly decreased m6A methylation in plasma cells (PCs) from MM patients and showed that the abnormal m6A level resulted mainly from upregulation of the demethylase fat mass and obesity-associated protein (FTO). Gain- and loss-of-function studies demonstrated that FTO plays a tumor-promoting and pro-metastatic role in MM. Combined m6A and RNA sequencing (RNA-seq) and subsequent validation and functional studies identified heat shock factor 1 (HSF1) as a functional target of FTO-mediated m6A modification. FTO significantly promotes MM cell proliferation, migration, and invasion by targeting HSF1/HSPs in a YTHDF2-dependent manner. FTO inhibition, especially when combined with bortezomib (BTZ) treatment, synergistically inhibited myeloma bone tumor formation and extramedullary spread in NOD-Prkdcem26Cd52il2rgem26Cd22/Nju (NCG) mice. We demonstrated the functional importance of m6A demethylase FTO in MM progression, especially in promoting extramedullary myeloma (EMM) formation, and proposed the FTO-HSF1/HSP axis as a potential novel therapeutic target in MM.

Whole-genome sequencing suggests a role of MIF in the pathophysiology of TEMPI syndrome.

TEMPI syndrome (telangiectasias, elevated erythropoietin level and erythrocytosis, monoclonal gammopathy, perinephric fluid collections, and intrapulmonary shunting) is a newly defined multisystemic disease with its pathophysiology largely unknown. Here, we report the whole-genome sequencing (WGS) analysis on the tumor-normal paired cells from a patient with TEMPI syndrome. WGS revealed somatic nonsynonymous single-nucleotide variants, including SLC7A8, NRP2, and AQP7. Complex structural variants of chromosome 2 were found, particularly within regions where some putative oncogenes reside. Of potential clinical relevance, duplication of 22q11.23 was identified, and the expression of the located gene macrophage migration inhibitory factor (MIF) was significantly upregulated in 3 patients with TEMPI syndrome. Importantly, the level of serum MIF in one patient with TEMPI syndrome was significantly decreased in accordance with the downtrend of plasma cells, M-protein, hemoglobin, and erythropoietin and the improvement of telangiectasias, perinephric fluid collections, and intrapulmonary shunting after treatment with plasma cell-directed therapy. In conclusion, our study provides insights into the genomic landscape and suggests a role of MIF in the pathophysiology of TEMPI syndrome.

The relationship among primary anatomic subsite and risk and distribution of second malignant neoplasms in patients with stage I/II diffuse large B-cell lymphoma: An analysis of the surveillance, epidemiology, and end results database.

BACKGROUND: Recent studies have reported that diffuse large B-cell lymphoma (DLBCL) involving different primary extranodal sites have distinct clinicopathological characteristics and prognosis. However, the risk of secondary malignant neoplasms (SMNs) in DLBCL survivors with different primary extranodal sites are unknown. METHODS: A total of 40,714 patients diagnosed with stage I/II DLBCL were included from the Surveillance, Epidemiology, and End Results (SEER) database from 1983 to 2015.The standardized incidence ratio (SIR) and absolute excess risk (AER) were used to assess the risk of SMNs. RESULTS: The results show that the risk of SMN was significantly higher in extranodal DLBCL than in the US general population (SIR, 1.18; 95% CI, 1.11-1.26), and the risk of developing SMN remains significantly elevated with increased latency. Moreover, there were multiple site-specific risk patterns. There was a 22%, 44%, 66%, 123% and 151% increased risk of SMN 10 years after primary gastrointestinal tract, head/neck, skeletal, lung and liver/pancreas DLBCL diagnosis, respectively. There was a significant decrease risk of SMN with increasing age at diagnosis for primary gastrointestinal tract and skeletal DLBCL. In addition, DLBCL patients with primary sites in the gastrointestinal tract, thyroid and liver/pancreas had the highest incidences of secondary stomach cancer, second thyroid cancer, and second hepatobiliary cancer, respectively, which indicated that the initial site of DLBCL may predict the type of SMN. CONCLUSIONS: The strategies for cancer surveillance after extranodal DLBCL diagnosis may need to be individualized according to the subsite of extranodal DLBCL.

Nanoparticles Dual Targeting Both Myeloma Cells and Cancer-Associated Fibroblasts Simultaneously to Improve Multiple Myeloma Treatment.

Cancer-associated fibroblasts (CAFs) and myeloma cells could mutually drive myeloma progression, indicating that drug delivery to kill both CAFs and myeloma cells simultaneously could achieve better therapeutic benefits than to kill each cell type alone. Here, we designed a dual-targeting drug delivery system by conjugating paclitaxel (PTX)-loaded poly(ethylene glycol)-poly(lactic acid) nanoparticles (NPs) with a cyclic peptide (CNPs-PTX) with a special affinity with platelet-derived growth factor/platelet-derived growth factor receptor (PDGFR-ß) overexpressed on both CAFs and myeloma cells. Cellular uptake experiments revealed that the cyclic peptide modification on CNPs could significantly enhance CNPs uptake by both CAFs and myeloma cells compared with unmodified NPs. Cytotoxicity tests showed that CNPs-PTX was more toxic to both CAFs and myeloma cells compared with its counterpart PTX-loaded conventional NPs (NPs-PTX). In vivo imaging and biodistribution experiments showed that CNPs could abundantly accumulate in tumors and were highly co-localized with CAFs and myeloma cells. The in vivo anti-tumor experiments confirmed that the anti-myeloma efficacy of CNPs-PTX was significantly stronger than that of NPs-PTX and free drugs. In summary, it is the first time that a dual-targeting strategy was utilized in the field of myeloma treatment through targeting both CAFs and myeloma cells simultaneously, which harbors a high potential of clinical translation for myeloma treatment.

[Corrigendum] siRNA-mediated inhibition of endogenous brain­derived neurotrophic factor gene modulates the biological behavior of HeLa cells.

Following the publication of this article, an interested reader drew to the authors' attention that, in Fig. 7 on p. 2757, sections of the data panels in Fig. 7A and B, showing the results of the non­transfected HeLa cell (Pnon group) and pGenesil­1­transfected HeLa cell (P0 group) experiments respectively, were strikingly similar. Both the Pnon and the P0 groups were control groups; upon re­examining their original data, the authors have realized that, when uploading the images, the data shown in Fig. 7B for the pGenesil­1­transfected HeLa cells (P0 group) were selected incorrectly. The authors were able to locate the data that were intended to have been shown in Fig. 7B; moreover, the text describing the number of migrated cells in the Results section also requires a correction. In the 'Downregulation of BDNF expression suppresses the migratory and invasive capabilities of HeLa cells' subsection, the text on lines 9­11 of this paragraph should be changed to the following (changed text is highlighted in bold): 'Migrated cells/field in the PBDNF1 group (37±17) were significantly less than those in the Pnon (105±31) and P0 (86±27) groups'. Likewise, the same correction to the text has been made to the Figure legend, as shown opposite. The revised version of Fig. 7, showing the correct data for Fig. 7B, is shown opposite. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this Corrigendum, and all of the authors agree to the publication of this Corrigendum. The authors sincerely apologize for this mistake, and regret any inconvenience this mistake has caused. [the original article was published on Oncology Reports 37: 2751-2760, 2017; DOI: 10.3892/or.2017.5569].

Mesenchymal Stem Cell-Derived Exosomes as a Novel Strategy for the Treatment of Intervertebral Disc Degeneration.

Intervertebral disc degeneration (IVDD) has been reported to be the most prevalent contributor to low back pain, posing a significant strain on the healthcare systems on a global scale. Currently, there are no approved therapies available for the prevention of the progressive degeneration of intervertebral disc (IVD); however, emerging regenerative strategies that aim to restore the normal structure of the disc have been fundamentally promising. In the last decade, mesenchymal stem cells (MSCs) have received a significant deal of interest for the treatment of IVDD due to their differentiation potential, immunoregulatory capabilities, and capability to be cultured and regulated in a favorable environment. Recent investigations show that the pleiotropic impacts of MSCs are regulated by the production of soluble paracrine factors. Exosomes play an important role in regulating such effects. In this review, we have summarized the current treatments for disc degenerative diseases and their limitations and highlighted the therapeutic role and its underlying mechanism of MSC-derived exosomes in IVDD, as well as the possible future developments for exosomes.

A Novel Scoring System for Risk Assessment of Elderly Patients With Cytogenetically Normal Acute Myeloid Leukemia Based on Expression of Three AQP1 DNA Methylation-Associated Genes.

Background: Aquaporin 1 (AQP-1), a transmembrane water channel protein, has been proven to involve in many diseases' progression and prognosis. This research aims to explore the prognostic value of AQP-1 in elderly cytogenetically normal acute myeloid leukemia (CN-AML). Methods: Complete clinical and expression data of 226 elderly patients (aged > 60) with cytogenetically normal acute myeloid leukemia (CN-AML) were downloaded from the databases of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). We have explored prognostic significance of AQP-1, investigated the underlying mechanism, and developed a novel scoring system for the risk assessment of elderly patients with AML based on AQP1 methylation. Results: In the first and second independent group, AQP1 shows lower expression in CN-AML than normal people, while high AQP1 expression and AQP1 promoter hypomethylation were related to better overall survival (OS; P < 0.05). To understand the underlying mechanisms, we investigated differentially expressed genes (DEGs), miRNA and lncRNA associated with AQP1 methylation. A three-gene prognostic signature based on AQP1 methylation which was highly correlated with OS was established, and the performance was validated by Permutation Test and Leave-one-out Cross Validation method. Furthermore, an independent cohort was used to verify the prognostic value of this model. Conclusions: AQP1 methylation could serve as an independent prognostic biomarker in elderly CN-AML, and may provide new insights for the diagnosis and treatment for elderly CN-AML patients.

Identification of distinctive long noncoding RNA competitive interactions and a six-methylated-gene prognostic signature in acute myeloid leukemia with -5/del(5q) or -7/del(7q).

BACKGROUND: Acute myeloid leukemia (AML) with -5/del(5q) or -7/del(7q) has special clinical and biological characteristics, but its molecular mechanisms and risk stratification remain unknown. METHODS: The RNA sequencing and DNA methylation of 23 patients with -5/del(5q) or -7/del(7q) and 128 patients with other subtypes of acute myeloid leukemia were obtained from The Cancer Genome Atlas (TCGA). The regulatory mechanisms of competitive endogenous RNA (ceRNA) network and DNA methylation on gene expression were explored. To find robust and specific risk stratification for this AML subtype, a prognostic model was established and evaluated through four independent data sets. RESULTS: We identified 966 differentially expressed long noncoding RNA, 2274 differentially expressed genes, and 47 differentially expressed microRNAs, and constructed a ceRNA network. After the integrated analysis of differentially methylated and expressed genes, 19 genes showed the opposite trend between the methylation variation and gene expression. An six-methylated-gene prognostic signature which highly correlated with overall survival was established, and the performance was validated by leave-one-out cross validation method and permutation test. Furthermore, the excellent prognostic value of this model was supported by an independent cohort, while specificity of this model was validated by three independent data sets, suggesting it as a predictive classifier with high efficiency for distinguishing those with -5/del(5q) or -7/del(7q) from other AML subtypes. CONCLUSIONS: The ceRNA network may provide new ideas for the diagnosis and treatment for patients with -5/del(5q) or -7/del(7q).The six-methylated-gene prognostic signature was a robust, specific, and clinically practical risk stratification for the outcome of patients with AML having -5/del(5q) or -7/del(7q).

Incidence and Mortality Trends and Risk Prediction Nomogram for Extranodal Diffuse Large B-Cell Lymphoma: An Analysis of the Surveillance, Epidemiology, and End Results Database.

Background: DLBCL is the most commonly occurring type of non-Hodgkin's lymphoma, which may be found at various extranodal sites. But little is known about the particular trends of extranodal DLBCL. Methods: A total of 15,882 extranodal DLBCL patients were included in incidence analysis from the Surveillance, Epidemiology, and End Results (SEER) database (1973-2015). The joinpoint regression software was used to calculate the annual percent change (APC) in rates. Nomograms were established by R software to predict overall survival (OS). Results: The extranodal DLBCL incidence continued to rise at a rate of 1.6% (95% CI, 0.4-2.8, p < 0.001) per year over the study period, until it declined around 2003. The incidence-based mortality trend of extranodal DLBCL had a similar pattern, with a decrease happening around 1993. Five-year survival rates improved dramatically from the 1970s to 2010s (44.15 vs. 63.7%), and the most obvious increase occurred in DLBCL patients with primary site in the head/neck. The C-index showed a value for OS of 0.708, which validated the nomograms performed well and were able to forecast the prognosis of patients with extranodal DLBCL. The calibration curves showed satisfactory consistency between true values and predicted values for 1-, 5-, and 10-year overall survival, respectively. Conclusions: The incidence and incidence-based mortality of extranodal DLBCL had been increasing for decades, followed by a promising downward trend in recent years. These findings may help scientists identify disease-related risk factors and better manage the disease. The prediction signature cloud identifies high-risk patients who should receive effective therapies to prevent the fatal nature of this disease, and low-risk patients to reduce over-treatment.

miR-221/222-Mediated Inhibition of Autophagy Promotes Dexamethasone Resistance in Multiple Myeloma.

Inherent or acquired resistance to chemotherapeutic drugs is still an obstacle for the treatment of multiple myeloma (MM). MicroRNA dysregulation is related to the development of chemoresistance in cancers. However, its role in chemoresistance of MM is largely unknown. Here we demonstrated that miR-221/222 were upregulated in plasma cells from patients with MM, especially those with relapsed or refractory disease. Moreover, expression levels of miR-221/222 were inversely correlated with dexamethasone (Dex) sensitivity of human MM cell lines. Importantly, we found that Dex induced pro-death autophagy in MM cells and the inhibition of autophagy significantly decreased Dex-induced cell death. Mechanistically, autophagy-related gene 12 (ATG12) was identified as a novel target gene of miR-221/222, and miR-221/222 overexpression inhibited autophagy by directly targeting ATG12 and the p27kip (p27)-mammalian target of rapamycin (mTOR) pathway. Indeed, Dex treatment decreased the expression of miR-221/222, thereby activating the ATG12/p27-mTOR autophagy-regulatory axis and inducing cell death in Dex-sensitive MM cells. Furthermore, both in vitro and in vivo results showed that the inhibitions of miR-221/222 increased the expression of ATG12 and p27 and functionally induced extended autophagy and cell death of MM cells. In conclusion, our findings demonstrated the crucial role of the miR-221/222-ATG12/p27-mTOR autophagy-regulatory axis in Dex resistance of MM, and they suggest potential prediction and treatment strategies for glucocorticoid resistance.

Clinical characteristics and prognosis of immunoglobulin D myeloma in the novel agent era.

Immunoglobulin D (IgD) myeloma is a rare subtype that used to lead to a poor outcome. To investigate the current clinical features, cytogenetic changes and survival of patients with IgD myeloma under novel treatments, we analysed 47 patients with IgD myeloma, 31 men and 16 women, with a median age of 54.5 years. We found that IgD myeloma was associated with higher frequencies of anaemia, renal failure, and hypercalcemia and higher levels of serum LDH compared with non-IgD myeloma. More than 90% of patients with IgD myeloma had at least one cytogenetic abnormality demonstrated by fluorescence in situ hybridisation (FISH). IGH translocations were the most common abnormalities, which were mainly caused by t(11;14). Moreover, 36.2% of patients were at the Revised International Staging System (RISS) stage III when diagnosed. Those patients had significantly shorter PFS and OS compared with patients at RISS stages I and II. In conclusion, IgD myeloma has specific clinical characteristics. The RISS grade was shown to be a simple and effective method to predict the prognosis of patients with IgD myeloma.

MicroRNA-324-5p suppresses the migration and invasion of MM cells by inhibiting the SCFß-TrCP E3 ligase.

Multiple myeloma (MM) is a cytogenetically heterogeneous malignancy of plasma cells in bone marrow. Among the cytogenetic abnormalities of MM, del(17p) is a well-recognized high-risk genetic lesion associated with the late stage and progression of the disease. MicroRNA (miR)-324-5p, located at 17p13.1, was identified to be involved in the dysregulation of a number of types of malignant disease. However, whether miR-324-5p is associated with the development and progression of MM remains unknown. In the present study, the expression status of miR-324-5p in MM, and its effect on the migratory and invasive ability of MM cells were investigated. Using ubiquitination pathway polymerase chain reaction array, the inhibitory effect of miR-324-5p on the ubiquitinated proteins was investigated. It was identified that miR-324-5p levels were decreased in samples from patients with MM and MM cell lines. Increased expression of miR-324-5p by transfection of miR-324-5p mimic suppressed the proliferative, migratory and invasive abilities of MM.1R cells. Furthermore, increased expression of miR-324-5p in MM.1R cells inhibited the ubiquitination pathway and decreased the levels of ubiquitination-associated proteins, particularly the Skp1-Cullin1-F-box ß-transducin repeat-containing protein (SCFß-TrCP) E3 ligase. In addition, the results of the present study demonstrated that the SCFß-TrCP E3 ligase may contribute to the suppression of MM cell motility by inhibiting the expression of metastasis-associated genes, including metastasis suppressor 1. In conclusion, the results of the present study suggested that miR-324-5p may act as a tumor suppressor by impairing the motility of MM cells by suppressing the ubiquitination pathway.

MicroRNA-324-5p regulates stemness, pathogenesis and sensitivity to bortezomib in multiple myeloma cells by targeting hedgehog signaling.

Chromosome 17p deletions are present in 10% of patients with newly diagnosed multiple myeloma (MM), and are associated with inferior prognosis. miR-324-5p is located on chromosome 17p, and shows diverse functions in different types of cancers. However, its role in MM is largely unknown. Here we found the expression of miR-324-5p was decreased in MM, especially in del(17p) MM. In contrast, the expression of hedgehog (Hh) signaling components was elevated, indicating a correlation between miR-324-5p and Hh signaling in MM. Hh signaling is important for the pathogenesis of MM and maintenance of MM stem cell compartment. Indeed, overexpression of miR-324-5p significantly decreased Hh signaling components Smo and Gli1, and functionally reduced cell growth, survival as well as stem cell compartment in MM. Moreover, miR-324-5p potentiated the anti-MM efficacy of bortezomib through regulating the activities of multidrug-resistance proteins and the expression of Bcl-2 family genes. Consistent results were obtained in vivo. Finally, miR-324-5p overcame the protective effect of bone marrow stromal cells on MM cells. Taken together, our data demonstrate that miR-324-5p is essential for MM pathogenesis and downregulation of miR-324-5p is a novel mechanism of Hh signaling activation in MM. Therefore, targeting miR-324-5p provides a potential therapeutic strategy for MM.