OBJECTIVE: To explore the significance of the plasma cell percentage and immature plasma cells in the prognosis of patients with multiple myeloma (MM). METHODS: The clinical data of 126 newly diagnosed MM patients in Gansu Provincial Hospital from June 2017 to November 2022 were retrospectively analyzed. The enrolled patients were divided into a higher plasma cell percentage group (group A) and a lower plasma cell percentage group (group B) according to the median plasma cell percentage (33.5%). The clinicopathological data of the two groups were compared, and the effect of plasma cell percentage on the prognosis of MM patients was analyzed using survival curves. On this basis, group A and group B were divided into subgroups with immature plasma cells (A1 group, B1 group) and subgroups without immature plasma cells (A2 group, B2 group), respectively, then the survival curves were used to analyze the effect of immature plasma cells on the prognosis of MM patients. RESULTS: Among the 126 patients with MM, the proportions of patients with ISS stage III, elevated β₂-microglobulin(β₂-MG) level, and immature plasma cells in Group A were significantly higher compared those in Group B ( P =0.015, P =0.028, P =0.010). The median overall survival(OS) and progression-free survival(PFS) of group A were 32 months and 10 months, respectively. The median OS of group B was not reached, and the median PFS was 32 months. The 3-year OS rates of patients in group A and group B were 46.7% and 62.2%, respectively ( P =0.021), and the 3-year PFS were 29.2% and 42.5%, respectively ( P =0.033). There were no significant differences in OS and PFS between group A1 and group A2, or between group B1 and group B2 ( P >0.05). Multivariate COX survival analysis showed that the plasma cell percentage ≥33.5%（HR=1.253, 95%CI : 0.580-2.889, P =0.018）, age ≥65 years (HR=2.206, 95%CI : 1.170-3.510, P =0.012), lactate dehydrogenase(LDH) ≥250 U/L (HR=1.180, 95%CI : 0.621-2.398, P =0.048) and β₂-MG ≥3.5 mg/L (HR=1.507, 95%CI : 0.823-3.657, P =0.036) were independent risk factors affecting OS in MM patients. CONCLUSION MM patients with a higher plasma cell percentage (≥33.5%) at the initial diagnosis have a later disease stage, poorer OS and PFS, compared to the patients with a lower percentage(<33.5%) of plasma cells. The presence or absence of immature plasma cells has no significant impact on the survival of MM patients.
Humans ; Multiple Myeloma/pathology* ; Prognosis ; Plasma Cells/cytology* ; Retrospective Studies ; Male ; Female ; Middle Aged ; Aged ; Bone Marrow

OBJECTIVE: Photodynamic therapy has become an important method in clinical tumor treatment. This study aimed to investigate the effects of hematoporphyrin on multiple myeloma (MM) and its potential applications. METHODS: The MM cell line RPMI 8226 was treated with hematoporphyrin derivative (HPD), and CCK-8 assay was used to determine cell viability, apoptosis was detected by flow cytometry, intracellular reactive oxygen species (ROS) levels were measured using a detection kit combined with flow cytometry, and Western blot assay was used to detect apoptosis-related proteins and key signaling pathway protein levels. RESULTS: The optimal incubation time for the maximum absorption of HPD in RPMI 8226 cells was 4 hours. HPD significantly inhibited the proliferation of RPMI 8226 cells in a dose- and illumination time-dependent manner ( r =0.981; r =0.961). Additionally, HPD induced apoptosis in RPMI 8226 cells, but had no significant inhibitory effect on peripheral blood mononuclear cells derived from healthy individuals. HPD combined with illumination treatment significantly increased the intracellular ROS level, upregulated the expression of apoptosis-related proteins such as cleaved PARP, cleaved caspase-3 and Bax, and down-regulated the expression of proteins that maintain cell survival, such as NF-κB and Akt. CONCLUSION The HPD can inhibit the proliferation and induce apoptosis of multiple myeloma cells.
Humans ; Multiple Myeloma/pathology* ; Hematoporphyrins/pharmacology* ; Apoptosis/drug effects* ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Cell Proliferation/drug effects* ; Photochemotherapy ; Cell Survival/drug effects* ; Signal Transduction

Humans ; Herpesvirus 4, Human ; Epstein-Barr Virus Infections/complications* ; Multiple Myeloma/complications* ; Lymphoma, Large B-Cell, Diffuse/pathology*

Multiple myeloma(MM)is a systemic malignancy of plasma cells.Nowadays,the basic research on MM is flourishing with the continuous optimization and innovation of mouse models of MM.Heterologous mouse models of MM established with human-derived cells and immunodeficient mice have been applied in assessing drug efficacy,exploring drug resistance mechanisms,and observing tumor-bone marrow microenvironment interactions.In the last decades,the homologous mouse models of MM established with murine-derived cells or gene-editing technologies have been widely used in the research on the pathogenesis and drug development.Additionally,the stable modeling of targeted organ injury will be a key problem to be tackled in this field.This review summarizes the characteristics and application progress of mouse models of MM.
Humans ; Animals ; Mice ; Multiple Myeloma/pathology* ; Bone Marrow/pathology* ; Disease Models, Animal ; Drug Resistance ; Tumor Microenvironment

Bone marrow microenvironment is a highly complex environment surrounding tumor, which plays an important role in the survival, proliferation, drug resistance and migration of multiple myeloma (MM) cells. As an important cellular component in tumor microenvironment, tumor-associated macrophages(TAM) has attracted attention due to its key role in tumor progression and drug resistance. Targeting TAM has shown potential therapeutic value in cancer treatment. In order to clarify the role of macrophages in MM progression, it is necessary to understand the differentiation of TAM and its characteristics of promoting MM. This paper reviews the research progress on how TAM is programmed in MM and the mechanism of TAM promoting tumor development and drug resistance.
Humans ; Multiple Myeloma/pathology* ; Tumor-Associated Macrophages ; Macrophages/pathology* ; Cell Differentiation ; Tumor Microenvironment

OBJECTIVE: To investigate the effect of pure Chinese herbal extract Mangiferin on the malignant biological behaviors of multiple myeloma (MM) cells, and to analyze the molecular mechanism of the anti-myeloma effect of Mangiferin, so as to provide experimental basis for MM replacement therapy. METHODS: U266 and RPMI8226 of human MM cell lines were intervened with different concentrations of Mangiferin. Cell proliferation was detected by CCK-8 method. Annexin V/PI double staining flow cytometry was used to detect cell apoptosis. Western blot was used to detect the expression of apoptosis and related signaling pathway proteins, and real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of matrix metalloproteinase (MMP) and CXC chemokine receptor (CXCR) family. RESULTS: Mangiferin could inhibit the proliferation activity of U266 and RPMI8226 cells and induce cells apoptosis. After Mangiferin intervened in U266, RPMI8226 cells for 48 h, the expression of Bcl-2 family pro-apoptotic protein Bax was up-regulated, while the expression of survivin and Bcl-xL proteins was down-regulated and caspase-3 was hydrolyzed and activated to promote cell apoptosis, besides, the expression of Bcl-2 protein in U266 cells was also significantly down-regulated to induce apoptosis (P<0.05). After Mangiferin intervenes in MM cells, it can not only increase the expression level of tumor suppressor p53, but also induce programmed cell death of MM cells by inhibiting the expression of anti-apoptotic molecules and down-regulating the phosphorylation levels of AKT and NF-κB. In addition, after the intervention of Mangiferin, the expressions of CXCR4, MMP2 and MMP9 in U266 cells were down-regulated (P<0.05), while there is no effect on the expressions of CXCR2, CXCR7 and MMP13 (P>0.05). However, the expressions of CXCR4, MMP9, and MMP13 in RPMI8226 cells were down-regulated (P<0.01), the expression of MMP2 was weakly affected, and the expression of CXCR2 and CXCR7 was basically not affected (P>0.05). CONCLUSION Mangiferin can inhibit the proliferation and induce apoptosis of MM cells, and its mechanism may be related to inhibiting the activation of NF-κB signaling pathway, affecting the expression of Bcl-2 family proteins, and inhibiting the expression of core members of MMP and CXCR family.
Humans ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; Matrix Metalloproteinase 13 ; Cell Line, Tumor ; NF-kappa B ; Multiple Myeloma/pathology* ; Cell Proliferation ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2

OBJECTIVE: To investigate the biological function of miR-203a-5p and the underlying mechanism in multiple myeloma (MM). METHODS: Three miRNA expression profiles (GSE16558, GSE24371 and GSE17498) were downloaded from the GEO database. The three miRNA expression profiles contained 131 MM samples and 17 normal plasmacyte samples. The robust rank aggregation (RRA) method was used to identify the differentially expressed miRNAs between MM and normal plasmacytes. In order to carry out cytological experiments, MM cell line with stable over-expression of miR-203a-5p was constructed with lentivirus. Expression levels of miR-203a-5p in MM cells were quantified by qRT-PCR. The effects of miR-203a-5p on MM cells were investigated using assays of cell viability and cell cycle. Cell proliferation was measured using the Cell Counting kit (CCK)8 assay. The percentage of cells in each cell cycle was measured with a FACSCalibur system. Xenograft tumor models were established to evaluate the role of miR-203a-5p in tumorigenesis in vivo . To elucidate the underlying molecular mechanisms of miR-203a-5p in mediating cell proliferation inhibition and cell cycle arrest in MM, we used TargetScan and miRanda to predict the candidate targets of miR-203a-5p. The potential target of miR-203a-5p in MM cells was explored using the luciferase reporter assay, qRT-PCR, and Western blot. RESULTS: An integrated analysis of three MM miRNA expression datasets showed that the levels of miR-203a-5p in MM were notably downregulated compared with those in normal plasmacytes. Accordingly, the relative expression levels of miR-203a-5p were decreased in MM cell lines. In addition, overexpression of miR-203a-5p inhibited the proliferation and cell cycle progression of RPMI8226 and U266 cells. In vivo experiments demonstrated that upregulation of miR-203a-5p expression could significantly inhibit the tumorigenesis of subcutaneous myeloma xenografts in nude mice. Mechanistic investigation led to the identification of Jagged 1 (JAG1) as a novel and direct downstream target of miR-203a-5p. Interestingly, the reintroduction of JAG1 abrogated miR-203a-5p-induced MM cell growth inhibition and cell cycle arrest. CONCLUSION Our data demonstrate that miR-203a-5p inhibits cell proliferation and cell cycle progression in MM cells by targeting JAG1, supporting the utility of miR-203a-5p as a novel and potential therapeutic agent for miRNA-based MM therapy.
Animals ; Mice ; Humans ; Multiple Myeloma/pathology* ; Cell Line, Tumor ; Mice, Nude ; MicroRNAs/metabolism* ; Cell Division ; Cell Proliferation ; Disease Models, Animal ; Carcinogenesis/genetics* ; Gene Expression Regulation, Neoplastic ; Jagged-1 Protein/metabolism*

The multiple myeloma (MM), the second most common hematologic malignancy, is malignant proliferative disease of plasma cells. Although the application of many targeted drugs has significantly prolonged the survival time of MM patients, it is still an incurable disease. In recent years, the immunosuppression caused by interaction between tumor microenvironment(TME) and tumor cells has attracted people's attention gradually. As a kind of immunosuppressive cells in TME, regulatory T cells (Treg) play an important role in the progress of MM. Treg is related to the proliferation and metastasis of tumors, and can lead to the progress of MM by promoting the angiogenesis and generating immunosuppressive TME. In this review, we briefly summarized the latest research progress on the impact of Treg on the pathogenesis of MM.
Humans ; Multiple Myeloma/pathology* ; T-Lymphocytes, Regulatory/pathology* ; Immune Tolerance ; Plasma Cells/pathology* ; Immunosuppression Therapy ; Tumor Microenvironment

OBJECTIVE: To explore the biological function of LINC00174 in multiple myeloma (MM). METHODS: Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expressions of LINC00174 and miR-150 in peripheral blood of MM patients and MM cell lines. EdU staining and flow cytometry were used to detect the effects of LINC00174 and miR-150 on the proliferation and apoptosis of MM cells. Western blot was used to detect the expressions of proliferation marker nuclear-related antigen Ki67, apoptosis-related protein cleaved caspase-3 and transcription factor forkhead box protein P1 (FOXP1). Bioinformatics and dual-luciferase reporter assay were used to verify the targeting relationship between LINC00174 and miR-150 and the targeting relationship between miR-150 and FOXP1. RESULTS: The level of LINC00174 was significantly increased in peripheral blood of MM patients and MM cell lines (P <0.05). Compared with NC-siRNA group, the expression of LINC00174 was significantly reduced in LINC00174-siRNA group, the proliferation of U266 cells was reduced, the apoptosis rate was significantly increased, the level of Ki67 protein was reduced, and the level of cleaved caspase-3 protein was increased (all P <0.05). LINC00174 targeted regulation of the expression of miR-150. Compared with LINC00174-siRNA+NC inhibitor group, the expression of miR-150 in U266 cells in LINC00174-siRNA+miR-150 inhibitor group was significantly reduced, the cell proliferation was enhanced, the apoptosis rate was reduced, the level of Ki67 protein was increased, and the level of cleaved caspase-3 was decreased (all P <0.05). FOXP1 is the target gene of miR-150. Compared with NC mimic group, the expression of FOXP1 protein in miR-150 mimic group was significantly reduced, the cell proliferation was reduced, the apoptosis rate was significantly increased, Ki67 protein level was decreased, and the level of cleaved caspase-3 was increased. Compared with miR-150 mimic + vector group, the expression of FOXP1 protein in miR-150 mimic + pcDNA-FOXP1 group was significantly increased, the cell proliferation was enhanced, the apoptosis rate was reduced, the level of Ki67 protein was increased, and the level of cleaved caspase-3 was decreased (all P <0.05). CONCLUSION LINC00174 promotes the proliferation of MM cells and inhibits cell apoptosis by regulating the miR-150/ FOXP1 axis.
Humans ; Apoptosis ; Caspase 3 ; Cell Line, Tumor ; Cell Proliferation ; Forkhead Transcription Factors ; Ki-67 Antigen ; MicroRNAs/genetics* ; Multiple Myeloma/pathology* ; Repressor Proteins ; RNA, Small Interfering ; RNA, Long Noncoding/genetics*

Multiple myeloma (MM) is a malignant proliferative disease of plasma cells. Bone marrow mesenchymal stem cells (MSC) play an important role in the progression of MM. Compared with normal donor derived MSC (ND-MSC), MM patients derived MSC (MM-MSC) exhibit abnormalities in genes, signaling pathways, protein expression levels and cytokines secreted by themselves. Moreover, the exosomes of MM-MSC can interact with the bone marrow microenvironment. The above reasons can lead to MM cell proliferation, chemoresistance, impaired osteogenic differentiation of MM-MSC, and affect the immunomodulatory capacity of MM patients. In order to further understand the pathogenesis and related influencing factors of MM, this paper reviews the latest research progress of MM-MSC.
Humans ; Multiple Myeloma/pathology* ; Osteogenesis ; Mesenchymal Stem Cells ; Cell Differentiation ; Bone Marrow/metabolism* ; Bone Marrow Cells/metabolism* ; Tumor Microenvironment