Although the development of novel drugs has significantly improved the survival of patients with multiple myeloma (MM) over the past decades,the lack of effective therapeutic options for relapsed and refractory MM results in poor prognosis.The chimeric antigen receptor (CAR) T-cell therapy has achieved considerable progress in relapsed and refractory MM.Nevertheless,this therapy still has limitations such as cytokine release syndrome,neurotoxicity,and off-target effects.Natural killer (NK) cells,as a critical component of the innate immune system,play an essential role in tumor immunosurveillance.Therefore,CAR-modified NK (CAR-NK) cells are put forward as a therapeutic option for MM.The available studies have suggested that multiple targets can be used as specific therapeutic targets for CAR-NK cell therapy and confirmed their antitumor effects in MM cell lines and animal models.This review summarizes the anti-tumor mechanisms,biological characteristics,and dysfunction of NK cells in the MM tumor microenvironment,as well as the basic and clinical research progress of CAR-NK cells in treating MM.
Animals ; Receptors, Chimeric Antigen/metabolism* ; Multiple Myeloma/metabolism* ; Killer Cells, Natural/metabolism* ; Immunotherapy, Adoptive/methods* ; Tumor Microenvironment

Objective This study aims to construct and identify the chimeric antigen receptor NK92 (CAR-NK92) cells targeting NKG2D ligand (NKG2DL) (secreting IL-15Ra-IL-15) and verify the killing activity of NKG2D CAR-NK92 cells against multiple myeloma cells. Methods The extracellular segment of NKG2D was employed to connect 4-1BB and CD3Z, as well as IL-15Ra-IL-15 sequence to obtain a CAR expression framework. The lentivirus was packaged and transduced into NK92 cells to obtain NKG2D CAR-NK92 cells. The proliferation of NKG2D CAR-NK92 cells was detected by CCK-8 assay, IL-15Ra secretion was detected by ELISA and killing efficiency was detected by lactate dehydrogenase (LDH) assay. The molecular markers of NKp30, NKp44, NKp46, the ratio of apoptotic cell population, CD107a, and the secretion level of granzyme B and perforin were detected using flow cytometry. In addition, the cytotoxic mechanism of NKG2D CAR-NK92 cells on the tumor was verified by measuring the degranulation ability. Moreover, after NKG2D antibody inhibited effector cells and histamine inhibited tumor cells, LDH assay was utilized to detect the effect on cell-killing efficiency. Finally, the multiple myeloma tumor xenograft model was constructed to verify its anti-tumor activity in vivo. Results Lentiviral transduction significantly increased NKG2D expression in NK92 cells. Compared with NK92 cells, the proliferation ability of NKG2D CAR-NK92 cells was weaker. The early apoptotic cell population of NKG2D CAR-NK92 cells was less, and NKG2D CAR-NK92 cells had stronger cytotoxicity to multiple myeloma cells. Additionally, IL-15Ra secretion could be detected in its culture supernatant. NKp44 protein expression in NKG2D CAR-NK92 cells was clearly increased, demonstrating an enhanced activation level. Inhibition test revealed that the cytotoxicity of CAR-NK92 cells to MHC-I chain-related protein A (MICA) and MICB-positive tumor cells was more dependent on the interaction between NKG2D CAR and NKG2DL. After stimulating NKG2D CAR-NK92 cells with tumor cells, granzyme B and perforin expression increased, and NK cells obviously upregulated CD107α. Furthermore, multiple myeloma tumor xenograft model revealed that the tumors of mice treated with NKG2D CAR-NK92 cells were significantly reduced, and the cell therapy did not sensibly affect the weight of the mice. Conclusion A type of CAR-NK92 cell targeting NKG2DL (secreting IL-15Ra-IL-15) is successfully constructed, indicating the effective killing of multiple myeloid cells.
Humans ; Mice ; Animals ; Receptors, Chimeric Antigen/genetics* ; Interleukin-15 ; NK Cell Lectin-Like Receptor Subfamily K/metabolism* ; Granzymes ; Cell Line, Tumor ; Multiple Myeloma/therapy* ; Perforin

OBJECTIVE: To explore the clinical characteristics of nosocomial infection in newly diagnosed multiple myeloma(NDMM) patients, and establish a predictive nomogram model. METHODS: The clinical data of 164 patients with MM who were treated in Shanxi Bethune Hospital from January 2017 to December 2021 were retrospectively analyzed. The clinical characteristics of infection were analyzed. Infections were grouped as microbiologically defined infections and clinically defined infections. Univariate and multivariate regression models were used to analyze the risk factors of infection. A nomogram was established. RESULTS: 164 patients with NDMM were included in this study, and 122 patients (74.4%) were infected. The incidence of clinically defined infection was the highest (89 cases, 73.0%), followed by microbial infection (33 cases, 27.0%). Among 122 cases of infection, 89 cases (73.0%) had CTCAE grade 3 or above. The most common site of infection was lower respiratory in 52 cases (39.4%), upper respiratory tract in 45 cases (34.1%), and urinary system in 13 cases (9.8%). Bacteria(73.1%) were the main pathogens of infection. Univariate analysis showed that ECOG ≥2, ISS stage Ⅲ, C-reactive protein ≥10 mg/L, serum Creatinine ≥177 μmol/L had higher correlation with nosocomial infection in patients with NDMM. Multivariate regression analysis showed that C-reactive protein ≥10 mg/L (P＜0.001), ECOG ≥2 (P=0.011) and ISS stage Ⅲ （P=0.024） were independent risk factors for infection in patients with NDMM. The nomogram model established based on this has good accuracy and discrimination. The C-index of the nomogram was 0.779（95%CI: 0.682-0.875）. Median follow-up time was 17.5 months, the median OS of the two groups was not reached (P=0.285). CONCLUSION Patients with NDMM are prone to bacterial infection during hospitalization. C-reactive protein ≥10 mg/L, ECOG ≥2 and ISS stage Ⅲ are the risk factors of nosocomial infection in NDMM patients. The nomogram prediction model established based on this has great prediction value.
Humans ; Nomograms ; Multiple Myeloma/metabolism* ; Prognosis ; Retrospective Studies ; Cross Infection ; C-Reactive Protein

OBJECTIVE: To investigate the biological effects and its relative mechanism of decitabine combined with anlotinib on multiple myeloma cells. METHODS: The human MM cell lines and primary cells were treated with different concentrations of decitabine, anlotinib, and decitabine+anlotinib, respectively. The cell viability was detected and combination effect was calculated by CCK-8 assay. The apoptosis rate was measured by flow cytometry and the level of c-Myc protein was determined by Western blot. RESULTS: Both decitabine and anlotinib could effectively inhibit the proliferation and induce the apoptosis of MM cell lines NCI-H929 and RPMI-8226. The effect of combined treatment on the inhibition of cell proliferation and induction of apoptosis was stronger than that of single-drug treatment. The combination of the two drugs also showed strong cytotoxicity in primary MM cells. Decitabine and anlotinib could down-regulate the level of c-Myc protein in MM cells and the c-Myc level in the combination group was the lowest. CONCLUSION Decitabine combined with anlotinib can effectively inhibit the proliferation and induce apoptosis of MM cells, which provides a certain experimental basis for the treatment of human MM.
Humans ; Multiple Myeloma/metabolism* ; Decitabine ; Cell Line, Tumor ; Apoptosis ; Cell Proliferation

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*

CUDC-101, an effective and multi-target inhibitor of epidermal growth factor receptor (EGFR), histone deacetylase (HDAC), and human epidermal growth factor receptor 2 (HER2), has been reported to inhibit many kinds of cancers, such as acute promyelocytic leukemia and non-Hodgkin's lymphoma. However, no studies have yet investigated whether CUDC-101 is effective against myeloma. Herein, we proved that CUDC-101 effectively inhibits the proliferation of multiple myeloma (MM) cell lines and induces cell apoptosis in a time- and dose-dependent manner. Moreover, CUDC-101 markedly blocked the signaling pathway of EGFR/phosphoinositide-3-kinase (PI3K) and HDAC, and regulated the cell cycle G2/M arrest. Moreover, we revealed through in vivo experiment that CUDC-101 is a potent anti-myeloma drug. Bortezomib is one of the important drugs in MM treatment, and we investigated whether CUDC-101 has a synergistic or additive effect with bortezomib. The results showed that this drug combination had a synergistic anti-myeloma effect by inducing G2/M phase blockade. Collectively, our findings revealed that CUDC-101 could act on its own or in conjunction with bortezomib, which provides insights into exploring new strategies for MM treatment.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis ; Bortezomib/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; ErbB Receptors/antagonists & inhibitors* ; G2 Phase Cell Cycle Checkpoints ; Histone Deacetylase Inhibitors/pharmacology* ; Histone Deacetylases/metabolism* ; M Cells ; Multiple Myeloma/drug therapy*

OBJECTIVE: To investigate the effect of adipocytes in the bone marrow microenvironment of patients with multiple myeloma (MM) on the pathogenesis of MM. METHODS: Bone marrow adipocytes (BMA) in bone marrow smears of health donors (HD) and newly diagnosed MM (ND-MM) patients were evaluated with oil red O staining. The mesenchymal stem cells (MSC) from HD and ND-MM patients were isolated, and in vitro co-culture assay was used to explore the effects of MM cells on the adipogenic differentiation of MSC and the role of BMA in the survival and drug resistance of MM cells. The expression of adipogenic/osteogenic differentiation-related genes PPAR-γ, DLK1, DGAT1, FABP4, FASN and ALP both in MSC and MSC-derived adipocytes was determined with real-time quantitative PCR. The Western blot was employed to detect the expression levels of IL-6, IL-10, SDF-1α, TNF-α and IGF-1 in the supernatant with or without PPAR-γ inhibitor. RESULTS: The results of oil red O staining of bone marrow smears showed that BMA increased significantly in patients of ND-MM compared with the normal control group, and the BMA content was related to the disease status. The content of BMA decreased in the patients with effective chemotherapy. MM cells up-regulated the expression of MSC adipogenic differentiation-related genes PPAR-γ, DLK1, DGAT1, FABP4 and FASN, but the expression of osteogenic differentiation-related gene ALP was significantly down-regulated. This means that the direct consequence of the interaction between MM cells and MSC in the bone marrow microenvironment is to promote the differentiation of MSC into adipocytes at the expense of osteoblasts, and the cytokines detected in supernatant changed. PPAR-γ inhibitor G3335 could partially reverse the release of cytokines by BMA. Those results confirmed that BMA regulated the release of cytokines via PPAR-γ signal, and PPAR-γ inhibitor G3335 could distort PPAR-γ mediated BMA maturation and cytokines release. The increased BMA and related cytokines effectively promoted the proliferation, migration and drug resistance of MM cells. CONCLUSION The BMA and its associated cytokines are the promoting factors in the survival, proliferation and migration of MM cells. BMA can protect MM cells from drug-induced apoptosis and plays an important role in MM treatment failure and disease progression.
Humans ; Osteogenesis/genetics* ; Bone Marrow/metabolism* ; Multiple Myeloma/metabolism* ; Drug Resistance, Neoplasm ; Peroxisome Proliferator-Activated Receptors/pharmacology* ; Cell Differentiation ; Adipogenesis ; Cytokines/metabolism* ; Adipocytes/metabolism* ; Bone Marrow Cells/metabolism* ; Cells, Cultured ; PPAR gamma/pharmacology* ; Tumor Microenvironment

OBJECTIVE: To investigate the expression of pyruvate kinase M2 (PKM2) in bone marrow mesenchymal stem cells (BMSCs) in myeloma bone disease (MBD) and its effect on osteogenic and adipogenic differentiation of BMSCs. METHODS: BMSCs were isolated from bone marrow of five patients with multiple myeloma (MM) (MM group) and five with iron deficiency anemia (control group) for culture and identification. The expression of PKM2 protein were compared between the two groups. The differences between osteogenic and adipogenic differentiation of BMSCs were assessed by using alkaline phosphatase (ALP) and oil red O staining, and detecting marker genes of osteogenesis and adipogenesis. The effect of MM cell line (RPMI-8226) and BMSCs co-culture on the expression of PKM2 was explored. Functional analysis was performed to investigate the correlations of PKM2 expression of MM-derived BMSCs with osteogenic and adipogenic differentiation by employing PKM2 activator and inhibitor. The role of orlistat was explored in regulating PKM2 expression, osteogenic and adipogenic differentiation of MM-derived BMSCs. RESULTS: Compared with control, MM-originated BMSCs possessed the ability of increased adipogenic and decreased osteogenic differentiation, and higher level of PKM2 protein. Co-culture of MM cells with BMSCs markedly up-regulated the expression of PKM2 of BMSCs. Up-regulation of PKM2 expression could promote adipogenic differentiation and inhibit osteogenic differentiation of MM-derived BMSCs, while down-regulation of PKM2 showed opposite effect. Orlistat significantly promoted osteogenic differentiation in MM-derived BMSCs via inhibiting the expression of PKM2. CONCLUSION The overexpression of PKM2 can induce the inhibition of osteogenic differentiation of BMSCs in MBD. Orlistat can promote the osteogenic differentiation of BMSCs via inhibiting the expression of PKM2, indicating a potential novel agent of anti-MBD therapy.
Humans ; Adipogenesis ; Bone Diseases/metabolism* ; Bone Marrow Cells ; Cell Differentiation ; Cells, Cultured ; Mesenchymal Stem Cells/physiology* ; Multiple Myeloma/metabolism* ; Orlistat/pharmacology* ; Osteogenesis/genetics*

OBJECTIVE: To observe the effects of Guizhi Fuling Capsule (GZFLC) on myeloma cells and explore the mechanisms. METHODS: MM1S and RPMI 8226 cells were co-cultured with different concentrations of serum and the cell experiments were divided into negative (10%, 20% and 40%) groups, GZFLC (10%, 20%, and 40%) groups and a control group. Cell counting kit-8 (CCK-8) assays and flow cytometry were used to detect the viability and apoptosis levels of myeloma cells. The effects on mitochondria were examined by reactive oxygen specie (ROS) and tetrechloro-tetraethylbenzimidazol carbocyanine iodide (JC-1) assays. Western blot was used to detect the expression of B cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), cleaved caspase-3, -9, cytochrome C (Cytc) and apoptotic protease-activating factor 1 (Apaf-1). RPMI 8226 cells (2 × 10⁷) were subcutaneously inoculated into 48 nude mice to study the in vivo antitumor effects of GZFLC. The mice were randomly divided into four groups using a completely randomized design, the high-, medium-, or low-dose GZFLC (840, 420, or 210 mg/kg per day, respectively) or an equal volume of distilled water, administered daily for 15 days. The tumor volume changes in and survival times of the mice in the GZFLC-administered groups and a control group were observed. Cytc and Apaf-1 expression levels were detected by immunohistochemistry. RESULTS: GZFLC drug serum decreased the viability and increased the apoptosis of myeloam cells (P<0.05). In addition, this drug increased the ROS levels and decreased the mitochondrial membrane potential (P<0.01). Western blot showed that the Bcl-2/Bax ratios were decreased in the GZFLC drug serum-treated groups, whereas the expression levels of cleaved caspase-3, -9, Cytc and Apaf-1 were increased (all P<0.01). Over time, the myeloma tumor volumes of the mice in the GZFLC-administered groups decreased, and survival time of the mice in the GZFLC-administered groups were longer than that of the mice in the control group. Immunohistochemical analysis of tumor tissues from the mice in the GZFLC-administered groups revealed that the Cytc and Apaf-1 expression levels were increased (P<0.05). CONCLUSION GZFLC promoted apoptosis of myeloma cells through the mitochondrial apoptosis pathway and significantly reduced the tumor volumes in mice with myeloma, which prolonged the survival times of the mice.
Mice ; Animals ; Caspase 3/metabolism* ; Reactive Oxygen Species/metabolism* ; Wolfiporia ; Multiple Myeloma/drug therapy* ; bcl-2-Associated X Protein/metabolism* ; Mice, Nude ; Apoptosis ; Mitochondria/metabolism*

OBJECTIVE: To investigate the efficacy and safety of plerixafor combined with granulocyte colony-stimulating factor (G-CSF) in mobilizing peripheral blood hematopoietic stem cells in patients with lymphoma. METHODS: The clinical data of lymphoma patients who received autologous hematopoietic stem cell mobilization using plerixafor combined with G-CSF from January 2019 to December 2021 were retrospectively analyzed. The patients received 3 kinds of mobilization regimens: front-line steady-state mobilization, preemptive intervention, and recuse mobilization. The acquisition success rate, excellent rate of collection, and incidence of treatment-related adverse reaction were counted. The influence of sex, age, disease remission status, bone marrow involvement at diagnosis, chemotherapy lines, number of chemotherapy, platelet count and number of CD34⁺ cells on the day before acquisition in peripheral blood on the collection results were analyzed to identify the risk factors associated with poor stem cell collection. RESULTS: A total of 43 patients with lymphoma were enrolled, including 7 cases who received front-line steady-state mobilization, 19 cases who received preemptive intervention, and 17 cases who received recuse mobilization. The overall acquisition success rate was 58.1% (25/43) after use of plerixafor combined with G-CSF, and acquisition success rate of front-line steady-state mobilization, preemptive intervention, and recuse mobilization was 100%, 57.9%(11/19), and 41.2%(7/17), respectively. The excellent rate of collection was 18.6%(8/43). A total of 15 patients experienced mild to moderate treatment-related adverse reactions. The number of CD34⁺ cells < 5 cells/μl in peripheral blood on the day before collection was an independent risk factor affecting stem cell collection. CONCLUSIONS Plerixafor combined with G-CSF is a safe and effective mobilization regimen for patients with lymphoma. The number of CD34⁺ cells in peripheral blood on the day before collection is an predictable index for the evaluation of stem cell collection.
Humans ; Antigens, CD34/metabolism* ; Granulocyte Colony-Stimulating Factor/therapeutic use* ; Hematopoietic Stem Cell Mobilization/methods* ; Hematopoietic Stem Cell Transplantation ; Heterocyclic Compounds/therapeutic use* ; Lymphoma/drug therapy* ; Multiple Myeloma/drug therapy* ; Retrospective Studies ; Transplantation, Autologous