Multiple myeloma mesenchymal stromal cells: Contribution to myeloma bone disease and therapeutics

Multiple myeloma is a hematological malignancy inwhich clonal plasma cells proliferate and accumulate within the bone marrow. The presence of osteolytic le-sions due to increased osteoclast(OC) activity and sup-pressed osteoblast(OB) function is characteristic of the disease. The bone marrow mesenchymal stromal cells(MSCs) play a critical role in multiple myeloma patho-physiology, greatly promoting the growth, survival, drug resistance and migration of myeloma cells. Here, we specifically discuss on the relative contribution of MSCs to the pathophysiology of osteolytic lesions in light of the current knowledge of the biology of my-eloma bone disease(MBD), together with the reported genomic, functional and gene expression differences between MSCs derived from myeloma patients(pMSCs) and their healthy counterparts(dMSCs). Being MSCs the progenitors of OBs, pMSCs primarily contribute to the pathogenesis of MBD because of their reduced osteogenic potential consequence of multiple OB inhibi-tory factors and direct interactions with myeloma cells in the bone marrow. Importantly, pMSCs also readily contribute to MBD by promoting OC formation and ac-tivity at various levels(i.e., increasing RANKL to OPG expression, augmenting secretion of activin A, uncou-pling ephrinB2-EphB4 signaling, and through augment-ed production of Wnt5a), thus further contributing to OB/OC uncoupling in osteolytic lesions. In this review, we also look over main signaling pathways involved in the osteogenic differentiation of MSCs and/or OB activity, highlighting amenable therapeutic targets; in parallel, the reported activity of bone-anabolic agents(at preclinical or clinical stage) targeting those signaling pathways is commented.

Follow-Up Study of a Multiple Myeloma Patient Successfully Treated with Clarithromycin (CAM), Low-Dose Lenalidomide and Low-Dose Dexamethasone: Significance and Possible Mechanism of Action of CAM as an Add-On Therapy

Background: Recently, high efficacy of the chemotherapeutic regimen combining clarithromycin (CAM) with lenalidomide (Len) and dexamethasone (Dex) (BiRD) in treating multiple myeloma (MM) patients has been reported. However, the exact mechanism of added CAM has not been fully elucidated. This case report will provide helpful information for understanding the significance and the mechanism of action of CAM as an add-on therapy. Patient: A 78-year-old female patient with IgA-λ type MM was treated with low-dose Len coupled with low-dose Dex (low Rd), and excellent response was achieved for long term, but she later became refractory to this treatment. Then, CAM was added to low Rd (low Rd-CAM, i.e., modified BiRD therapy). This add-on-therapy was found to be effective, but later suspended because of pneumonitis. Then, low-dose Len coupled with CAM (low R-CAM) treatment was applied;but effect of this Dex-free treatment was insufficient. Thus, low Rd-CAM was reapplied and satisfactory reduction of IgA was achieved. This fact suggests that low Rd-CAM is the favorable combination, Dex is requisite and CAM might have enhanced the effect of Dex. In this case, various serum cytokines were examined during the course of illness. Only interleukin-6 showed apparent increase, and tumor necrosis factor-α, transforming growth factor-β, soluble IL-2 receptors and C-reactive protein showed the slight increase during low Rd-CAM treatment. The results seem somewhat conflicting, but it seems that intricate cytokine response due to immune activation might have occurred during low Rd-CAM treatment.

A genetic variant study of bortezomib-induced peripheral neuropathy in Chinese multiple myeloma patients

Background:Bortezomib results in peripheral neuropathy(PN)in approximately 50%of patients,during multiple myeloma(MM)treatment,a complication known as Bortezomib-induced peripheral neuropathy(BIPN).The drug response varies among individuals.Genetic factor may play an important role in BIPN.Methods:A nextgeneration sequencing(NGS)panel containing 1659 targets from 233 genes was used to identify risk variants for developing BIPN in 204 MM patients who received bortezomib therapy.mRNA expression of MTHFR and ALDH1A1 in 62 peripheral blood samples was detected by real-time quantitative PCR(RT-qPCR).Serum homocysteine(Hcy)levels were detected in 40 samples by chemiluminescent microparticle immunoassay(CMIA).Results:Compared with the non-BIPN group(n=89),a total of 8 significantly associated single nucleotide polymorphisms(SNPs)were identified in the BIPN group(n=115):MTHFR(rs1801131,rs1801133,rs17421511),EPHX1(rs1051740),MME(rs2016848),ALDH1A1(rs6151031),HTR7(rs1935349)and CYP2A6(rs8192720).The mRNA expression level of MTHFR in newly diagnosed patients with peripheral neuritis after treatment(NP group)was lower than that of newly diagnosed patients without peripheral neuritis after treatment(NnP group)(1.70±0.77 vs.2.81±0.97,p=0.009).Serum Hcy levels were significantly higher in BIPN group than in non-BIPN group(11.66±1.79μmol/L vs.8.52±3.29μmol/L,p=0.016)and healthy controls(11.66±1.79μmol/L vs.8.55±2.13μmol/L,p≤0.001).Conclusion:CYP2A6,EPHX1,MTHFR,ALDH1A1,HTR7,MME and BIPN are linked in Chinese MM patients.BIPN is more likely to occur in patients with lower MTHFR mRNA expression,which might result in higher serum Hcy levels.

Imaging of multiple myeloma: Current concepts

Medical imaging is of crucial importance for diagnosis and initial staging as well as for differentiation of multiple myeloma(MM)from other monoclonal plasma cell diseases.Conventional radiography represents the reference standard for diagnosis of MM due to its wide availability and low costs despite its known limitations such as low sensitivity,limited specificity and its inability to detect extraosseous lesions.Besides conventional radiography,newer cross-sectional imaging modalities such as whole-body low-dose computed tomography(CT),whole-body magnetic resonance imaging(MRI)and18F-fluorodeoxyglucose(FDG)positron emission tomography(PET)/CT are available for the diagnosis of osseous and extraosseous manifestations of MM.Whole-body low-dose CT is used increasingly,replacing conventional radiography at selected centers,due to its higher sensitivity for the detection of osseous lesions and its ability to diagnose extraosseous lesions.The highest sensitivity for both detection of bone marrow disease and extraosseous lesions can be achieved with whole-body MRI and18F-FDG PET/CT.According to current evidence,MRI is the most sensitive method for initial staging while18F-FDG PET/CT allows monitoring of treatment of MM.There is an evolving role for assessment of treatment response using newer MR imagingtechniques.Future studies are needed to further define the exact role of the different imaging modalities for individual risk stratification and therapy monitoring.

Novel mechanism of drug resistance to proteasome inhibitors in multiple myeloma

Multiple myeloma(MM) is a cancer caused by uncontrolled proliferation of antibody-secreting plasma cells in bone marrow, which represents the second most common hematological malignancy. MM is a highly heterogeneous disease and can be classified into a spectrum of subgroups based on their molecular and cytogenetic abnormalities. In the past decade, novel therapies, especially, the first-in-class proteasome inhibitor bortezomib, have been revolutionary for the treatment of MM patients. Despite these remarkable achievements, myeloma remains incurable with a high frequency of patients suffering from a relapse, due to drug resistance. Mutation in the proteasome β5-subunit(PSMB5) was found in a bortezomib-resistant cell line generated via long-term coculture with increasing concentrations of bortezomib in 2008, but their actual implication in drug resistance in the clinic has not been reported until recently. A recent study discovered four resistance-inducing PSMB5 mutations from a relapsed MM patient receiving prolonged bortezomib treatment. Analysis of the dynamic clonal evolution revealed that two subclones existed at the onset of disease, while the other two subclones were induced. Protein structural modeling and functional assays demonstrated that all four mutations impaired the binding of bortezomib to the 20 S proteasome, conferring different degrees of resistance. The authors further demonstrated two potential approaches to overcome drug resistance by using combination therapy for targeting proteolysis machinery independent of the 20 S proteasome.

Gene signatures to therapeutics:Assessing the potential of ivermectin against t(4;14)multiple myeloma

BACKGROUND Multiple myeloma(MM)is a terminal differentiated B-cell tumor disease characterized by clonal proliferation of malignant plasma cells and excessive levels of monoclonal immunoglobulins in the bone marrow.The translocation,(t)(4;14),results in high-risk MM with limited treatment alternatives.Thus,there is an urgent need for identification and validation of potential treatments for this MM subtype.Microarray data and sequencing information from public databases could offer opportunities for the discovery of new diagnostic or therapeutic targets.AIM To elucidate the molecular basis and search for potential effective drugs of t(4;14)MM subtype by employing a comprehensive approach.METHODS The transcriptional signature of t(4;14)MM was sourced from the Gene Expression Omnibus.Two datasets,GSE16558 and GSE116294,which included 17 and 15 t(4;14)MM bone marrow samples,and five and four normal bone marrow samples,respectively.After the differentially expressed genes were identified,the Cytohubba tool was used to screen for hub genes.Then,the hub genes were analyzed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis.Using the STRING database and Cytoscape,protein–protein interaction networks and core targets were identified.Potential small-molecule drugs were identified and validated using the Connectivity Map database and molecular docking analysis,respectively.RESULTS In this study,a total of 258 differentially expressed genes with enriched functions in cancer pathways,namely cytokine receptor interactions,nuclear factor(NF)-κB signaling pathway,lipid metabolism,atherosclerosis,and Hippo signaling pathway,were identified.Ten hub genes(cd45,vcam1,ccl3,cd56,app,cd48,btk,ccr2,cybb,and cxcl12)were identified.Nine drugs,including ivermectin,deforolimus,and isoliquiritigenin,were predicted by the Connectivity Map database to have potential therapeutic effects on t(4;14)MM.In molecular docking,ivermectin showed strong binding affinity to all 10 identified targets,especially cd45 and cybb.Ivermectin inhibited t(4;14)MM cell growth via the NF-κB pathway and induced MM cell apoptosis in vitro.Furthermore,ivermectin increased reactive oxygen species accumulation and altered the mitochondrial membrane potential in t(4;14)MM cells.CONCLUSION Collectively,the findings offer valuable molecular insights for biomarker validation and potential drug development in t(4;14)MM diagnosis and treatment,with ivermectin emerging as a potential therapeutic alternative.

Treatment Efficacy and Safety of Bortezomib Combined with Dexamethasone and Lenalidomide Chemotherapy Regimen for Multiple Myeloma

Objective:To analyze the effect of bortezomib combined with dexamethasone and lenalidomide in the treatment of multiple myeloma.Methods:60 cases of multiple myeloma patients admitted to our hospital from January 2022 to December 2023 were selected randomly,with 30 cases in each group.Bortezomib combined with dexamethasone was administered in the control group,and bortezomib combined with dexamethasone and lenalidomide was given to the observation group,and the treatment effect was analyzed.Results:After treatment,CD^(3+)and CD^(4+)of the observation group were higher than that of the control group,CD^(8+)was lower than that of the control group,and the total treatment efficiency was higher,which was statistically significant(P<0.05),and there was no difference in the total incidence of adverse reactions between the two groups(P>0.05).Conclusion:Bortezomib combined with dexamethasone and lenalidomide is effective in the treatment of multiple myeloma as it regulates the immune function and is safe,thus it can be promoted in clinical practice.

Parametric and Non-Parametric Analysis of the Survival Times of Patients with Multiple Myeloma Cancer

Multiple myeloma (MM) is a type of cancer that remains incurable. In the last decade, most research into MM has focused on investigating the improvement in the therapeutic strategy. Our study assesses the survival probability of 48 patients diagnosed with MM based on parametric and non-parametric techniques. We performed parametric survival analysis and found a well-def- ined probability distribution of the survival time to follow three-parameter lognormal. We then estimated the survival probability and compared it with the commonly used non-parametric Kaplan-Meier survival analysis of the survival times. The comparison of the survival probability estimates of the two methods revealed a better survival probability estimate by the parametric method than the Kaplan-Meier. The parametric survival analysis is more robust and efficient because it is based on a well-defined parametric probabilistic distribution, hence preferred over the non-parametric Kaplan-Meier. This study offers therapeutic significance for further enhancement in the treatment strategy of multiple myeloma cancer.

Identify multiple myeloma stem cells: Utopia?

Multiple myeloma(MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells(CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activate stemness signaling(Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs.

Enhanced Precision Therapy of Multiple Myeloma Through Engineered Biomimetic Nanoparticles with Dual Targeting

Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations through the development of a potent MM-targeting chemotherapy strategy,which capitalized on the high binding affinity of alendronate for hydroxyapatite in the bone matrix and the homologous targeting of myeloma cell membranes,termed T-PB@M.The results from our investigations highlight the considerable bone affinity of T-PB@M,both in vitro and in vivo.Additionally,this material demonstrated a capability for drug release triggered by low pH conditions.Moreover,T-PB@M induced the generation of reactive oxygen species and triggered cell apoptosis through the poly(ADP-ribose)polymerase 1(PARP1)-Caspase-3-B-cell lymphoma-2(Bcl-2)pathway in MM cells.Notably,T-PB@M preferentially targeted bone-involved sites,thereby circumventing systemic toxic side effects and leading to prolonged survival of MM orthotopic mice.Therefore,this designed target-MM nanocarrier presents a promising and potentially effective platform for the precise treatment of MM.

Multiple myeloma survival in New South Wales, Australia, by treatment era to 2020

Objective: Australia has relatively high multiple myeloma(MM) incidence and mortality rates. Advancements in MM treatment over recent decades have driven improvements in MM survival in high-income countries;however, reporting in Australia is limited. We investigated temporal trends in population-wide MM survival across 3 periods of treatment advancements in New South Wales(NSW), Australia.Methods: Individuals with an MM diagnosis in the NSW Cancer Registry between 1985 and 2015 with vital follow-up to 2020, were categorized into 3 previously defined treatment eras according to their diagnosis date(1985±1995, chemotherapy only;1996±2007, autologous stem cell transplantation;and 2008±2015, novel agents including proteasome inhibitors and immunomodulatory drugs). Both relative survival and cause-specific survival according to Fine and Gray's competing risks cumulative incidence function were calculated by treatment era and age at diagnosis.Results: Overall, 11,591 individuals were included in the study, with a median age of 70 years at diagnosis. Five-year relative survival improved over the 36-year(1985±2020) study period(31.0% in 1985±1995;41.9% in 1996±2007;and 56.1% in 2008±2015). For individuals diagnosed before 70 years of age, the 5-year relative survival nearly doubled, from 36.5% in 1985±1995 to 68.5% in 2008±2015. Improvements for those > 70 years of age were less pronounced between 1985±1995 and 1996±2007;however, significant improvements were observed for those diagnosed in 2008±2015. Similar overall and age-specific patterns were observed for causespecific survival. After adjustment for gender and age at diagnosis, treatment era was strongly associated with both relative and cause-specific survival(P < 0.0001).Conclusions: Survival of individuals with MM is improving in Australia with treatment advances. However, older age groups continue to experience poor survival outcomes with only modest improvements over time. Given the increasing prevalence of MM in Australia, the effects of MM treatment on quality of life, particularly in older age, warrant further attention.

Development of a cell adhesion-based prognostic model for multiple myeloma:Insights into chemotherapy response and potential reversal of adhesion effects

Multiple myeloma(MM)is a hematologic malignancy notorious for its high relapse rate and development of drug resistance,in which cell adhesion-mediated drug resistance plays a critical role.This study integrated four RNA sequencing datasets(CoMMpass,GSE136337,GSE9782,and GSE2658)and focused on analyzing 1706 adhesionrelated genes.Rigorous univariate Cox regression analysis identified 18 key prognosis-related genes,including KIF14,TROAP,FLNA,MSN,LGALS1,PECAM1,and ALCAM,which demonstrated the strongest associations with poor overall survival(OS)in MM patients.To comprehensively evaluate the impact of cell adhesion on MM prognosis,an adhesion-related risk score(ARRS)model was constructed using Lasso Cox regression analysis.The ARRS model emerged as an independent prognostic factor for predicting OS.Furthermore,our findings revealed that a heightened cell adhesion effect correlated with tumor resistance to DNA-damaging drugs,protein kinase inhibitors,and drugs targeting the PI3K/Akt/mTOR signaling pathway.Nevertheless,we identified promising drug candidates,such as tirofiban,pirenzepine,erlotinib,and bosutinib,which exhibit potential in reversing this resistance.In vitro,experiments employing NCIH929,RPMI8226,and AMO1 cell lines confirmed that MM cell lines with high ARRS exhibited poor sensitivity to the aforementioned candidate drugs.By employing siRNA-mediated knockdown of the key ARRS model gene KIF14,we observed suppressed proliferation of NCIH929 cells,along with decreased adhesion to BMSCs and fibronectin.This study presents compelling evidence establishing cell adhesion as a significant prognostic factor in MM.Additionally,potential molecular mechanisms underlying adhesion-related resistance are proposed,along with viable strategies to overcome such resistance.These findings provide a solid scientific foundation for facilitating clinically stratified treatment of MM.

Identification of TNFRSF1A as a novel regulator of carfilzomib resistance in multiple myeloma

Multiple myeloma(MM)is a hematological tumor with high mortality and recurrence rate.Carfilzomib is a new-generation proteasome inhibitor that is used as the first-line therapy for MM.However,the development of drug resistance is a pervasive obstacle to treating MM.Therefore,elucidating the drug resistance mechanisms is conducive to the formulation of novel therapeutic therapies.To elucidate the mechanisms of carfilzomib resistance,we retrieved the GSE78069 microarray dataset containing carfilzomib-resistant LP-1 MM cells and parental MM cells.Differential gene expression analyses revealed major alterations in the major histocompatibility complex(MHC)and cell adhesion molecules.The upregulation of the tumor necrosis factor(TNF)receptor superfamily member 1A(TNFRSF1A)gene was accompanied by the downregulation of MHC genes and cell adhesion molecules.Furthermore,to investigate the roles of these genes,we established a carfilzomib-resistant cell model and observed that carfilzomib resistance induced TNFRSF1A overexpression and TNFRSF1A silencing reversed carfilzomib resistance and reactivated the expression of cell adhesion molecules.Furthermore,TNFRSF1A silencing suppressed the tumorigenesis of MM cells in immunocompetent mice,indicating that TNFRSF1A may lead to carfilzomib resistance by dampening antitumor immunity.Furthermore,our results indicated that TNFRSF1A overexpression conferred carfilzomib resistance in MM cells and suppressed the expression of MHC genes and cell adhesion molecules.The suppression of MHC genes and cell adhesion molecules may impair the interaction between immune cells and cancer cells to impair antitumor immunity.Future studies are warranted to further investigate the signaling pathway underlying the regulatory role of TNFRSF1A in MM cells.

Plasmacytosis mimicking multiple myeloma in angioimmunoblastic T-cell lymphoma:A case report and review of literature

BACKGROUND Angioimmunoblastic T-cell lymphoma(AITL)is a common subtype of peripheral T-cell lymphoma.Approximately half of patients with AITL may concurrently present with hypergammaglobulinemia.Increased numbers of plasma cells in the bone marrow are commonly observed at diagnosis.These tumors mimic plasma cell myelomas,hindering a conundrum of clinical diagnoses and potentially delaying appropriate treatment.CASE SUMMARY A 78-year-old woman experienced poor appetite,weight loss of 5 kg,fatigue 2 months before presentation,and shortness of breath 2 d before presentation,but no fever or night sweats.Physical examination revealed splenomegaly and many palpable masses over the bilateral axillary regions,approximately>2 cm in size,with rubbery consistency and no tenderness.Blood tests revealed anemia and thrombocytopenia,lactate dehydrogenase level of 153 U/L,total protein level of 10.9 g/dL,albumin to globulin ratio of 0.2,and immunoglobulin G level more than the upper limit of 3000 mg/dL.The free kappa and lambda light chain concentrations were 451 and 614 mg/L,respectively.A pathological examination confirmed the diagnosis of AITL.The initial treatment was the cyclophosphamide,epirubicin,vincristine,and prednisolone regimen.Following this treatment,pleural effusion was controlled,and the patient was discharged in a stable condition and followed up in our outpatient department.CONCLUSION This report highlights the importance of differentiating reactive plasmacytosis from plasma cell myeloma in patients with hypergammaglobulinemia.A precise diagnosis of AITL requires a comprehensive evaluation,involving clinical,immunophenotypic,and histological findings conducted by a multidisciplinary team to ensure appropriate treatment.

Orbital Involvement in Multiple Myeloma: A Case Report

Purpose: To report a retro-orbital localization of Multiple Myeloma (MM) describing its treatment and clinical result. Case report: A 50-years-old male patient with Magnetic Resonance Imaging (MRI) evidence of a retro-orbital mass with exophthalmos, due to the pathological diagnosis of MM, was referred for Radiation Therapy (RT). Discussion: The orbital involvement in Multiple Myeloma is rare and few cases are reported in the literature. The treatment of choice is RT alone with a prescribed dose ranging between 40 Gy and 45 Gy. In our patient the retro-orbital lesion, measuring 26 × 16 mm, was treated with Intensity Modulated Radiotherapy Technique (IMRT) delivering 4400 cGy with conventional fractionation. The treatment was well tolerated, the patient experienced a complete regression of the exophthalmos without any significant side effect.

Novel agents and new therapeutic approaches for treatment of multiple myeloma

This review summarizes the therapeutic strategies and the drugs actually in development for the management of myeloma patients. Multiple myeloma is caused by the expansion of monoclonal plasma cells and secretion of M-protein(immunoglobulins, Bence Jones protein and free light chains). Multiple myeloma still remains an incurable disease with a high incidence rate in the elderly, despite the introduction of several new therapeutic agents(bortezomib, lenalidomide and thalidomide) which have changed its natural history. The high heterogeneity of this disease leads to large differences in clinical responses to treatments. Thus, the choice of the best treatment is a difficult issue. However, the introduction of new drugs has made it possible to achieve high response rates and good quality respons-es with long-term disease control. Interactions between tumor cells and their bone marrow microenvironment play a pivotal role in the development, maintenance, and progression of myeloma, inducing also drug resistance. These knowledges have improved treatment options, leading to the approval of new drugs which not only target the malignant cell itself, but also its microenvironment. These agents are in preclinical/early clinical evaluation and they appear to further improve disease control, but their use is still not approved outside of clinical trials.

Effects of bortezomib combined with dexamethasone and thalidomide on bone metabolism regulating factors, immune function and renal function in patients with multiple myeloma complicated with renal insufficiency

Objective: To investigate the effects of bortezomib combined with dexamethasone and thalidomide on the levels of bone metabolism regulating factors, immune function and renal function in patients with multiple myeloma complicated with renal insufficiency. Methods:According to the random data table, a total of 90 patients with multiple myeloma complicated with renal insufficiency were divided into the control group (n=45) and observation group (n=45), patients in the two groups were treated with diuretic, hydration and other symptomatic and supportive treatment, on this basis, the control group were treated with cyclophosphamide, dexamethasone and thalidomide regimen treatment, and the patients in the observation group were given bortezomib, dexamethasone and thalidomide regimen treatment, before treatment (before chemotherapy) and after treatment (3 cycles of chemotherapy) the levels of bone metabolic regulating factors, immune function and renal function between the two groups were compared. Results: The difference of the levels of RANKL, TRACP-5b, CD3+, CD4+, CD8+, CD4+/CD8+, SCr, BUN in the two groups before treatment were not significant. Compared with the control groups levels after treatment, the levels of RANKL, TRACP-5b, CD8+, SCr and BUN in the observation group were significantly decreased, and the levels of CD3+, CD4+and CD4+/CD8+ were significantly increased, the difference was statistically significant. Conclusion: Bortezomib in combination with dexamethasone and thalidomide in treatment of multiple myeloma with renal insufficiency, can effectively reduce the level of bone metabolism in regulating factor, improve immune function and renal function, it has an important clinical value.

Analysis of the role of dihydromyricetin derived from vine tea(Ampelopsis grossedentata)on multiple myeloma by activating STAT1/RIG-I axis

Multiple myeloma(MM)is a plasma cell malignancy and remains incurable as it lacks effective curative approaches;thus,novel therapeutic strategies are desperately needed.The study aimed to explore the therapeutic role of dihydromyricetin(DHM)in MM and explore its mechanisms.Human MM and normal plasma samples,human MM cell lines,and normal plasma cells were used for in vitro experiments.Cell counting kit-8(CCK-8),flow cytometry,and trans-well assays were performed for the assessment of cell viability,apoptosis,migration,and invasion,respectively.Quantitative real-time polymerase chain reaction(qRT-PCR)was employed to assess the mRNA expression of signal transducer and activator of transcription 1(STAT1)and retinoic acid-inducible gene I(RIG-I).Western blotting was employed to assess E-cadherin,N-cadherin,signal transducer,STAT1,p-STAT1,and RIG-I protein expression.A tumor xenograft model was used for in vivo experiments.Here,dihydromyricetin(DHM)dose-dependently restrained viability,apoptosis,migration,and invasion,and facilitated apoptosis of U266 cells.After DHM treatment,the Ecadherin level was increased and the N-cadherin level was decreased in U266 and RPMI-8226 cells,suggesting the inhibitory effects of DHM on epithelial-mesenchymal transition(EMT)in MM.Besides,the levels of p-STAT1/STAT1 and RIG-I were down-regulated in MM.However,the STAT1 inhibitor fludarabine undid the suppressive effect of DMH on the malignant characteristics of U266 cells.Also,DHM inhibited MM tumor growth and EMT,and activated STAT1/RIG-I pathway in vivo.Collectively,this study first revealed that DHM can restrain EMT and tumor growth in MM by activating STAT1/RIG-I signaling,which provides a novel drug for the treatment of MM.

Infection in Multiple Myeloma: Microbiological Profile and Prognosis in Senegalese Patients

Introduction: Infections are additional factors of morbidity and mortality in multiple myeloma (MM), and the current recommendation is antibiotic prophylaxis. In sub-Saharan Africa, few data on infectious complications of MM are available. We aim to describe the microbiological features of infections in MM, and their impact on survival in Senegalese patients. Methods: A retrospective (January 2005-January 2022), analytic, multicenter study on infections in patients followed for MM (IMWG criteria) in Senegalese clinical hematology services. The socio-epidemiological, diagnostic, microbiological, evolutionary and survival aspects were analyzed. Results: The study included 106 patients with multiple myeloma who had an infection at admission or during the treatment. Ten patients have the comorbidity (hypertension, lupus, type 2 diabetes). These patients had 136 infectious events identified at diagnosis (79.2%) or during chemotherapy (20.8%). The sites of infection are lung (42.6%), urinary (29.4%), dermatological (6.6%), digestive (5.2%), osteoarticular (4.4%), ear, nose and throat (3.7%), central nervous system (1.5%), or without site. We recorded 26.4% of patients with multi-site infections. The causal pathogens are bacteria (Gram-negative bacilli: 22.1%;Gram positive bacilli: 9.5%, Mycobacterium tuberculosis: 13.3%), parasitique (plasmodium falciparum 6.6%), viruses (SARS-COV2: 2.9%, VZV: 2.2%) and fungal (2.9%). Survival was reduced in patients who had an infection at the time of multiple myeloma diagnosis (p: 0.189) and those who had multiple infectious foci (p: 0.011). Conclusion: Infections in multiple myeloma are more frequent at diagnosis. The germs are varied and mostly bacteria, particularly gram-negative bacteria, and Kochs bacillus. Our study reveals that multiple infectious foci are a poor prognosis factor. It is necessary to evaluate the infectious risk early, and to adopt an antibiotic prophylaxis based on our tropical environment.

Significance of elevated serum concentration of type Ⅰ collagen metabolites and its correlation with serum interleukin 6 activities in multiple myeloma

In this study, serum concentrations of carboxyterminal propeptide of type Ⅰ collagen(PICP) and carboxyterminal cross-linked telopeptide of type Ⅰ collagen (ICTP), which represent the rates of synthesis and degradation of type Ⅰ collagen, were determined by radioimmunoassay in 56 patients with multiple myeloma (MM) and 22 healthy controls. It was discovered that serum concentrations of both PICP and ICTP were higher in MM than those in healthy controls (P<0. 01 ). With the disease progressing and the number of bone lesions increasing,serum concentration of ICTP elevated while serum concentration of PICP showed no significant change. Neither serum PICP nor ICTP concentration was related to M-component classes. Our results indicated that serum ICTP concentration was a good serological marker to reflect severity of bone lesions in MM and elevated serum PICP concentration might be due to compensatory increase in type Ⅰ collagen synthesis. Moreover, we also found that serum ICTP concentrations in MM correlated with serum interleukin-6 (IL-6) activities (r= 0. 610, P< 0. 01),which confirms the effectiveness of IL-6 as an osteoclast activating factor.