RESUMEN
Studies have shown that bortezomib resistance in multiple myeloma (MM) is mediated by the abnormalities of various molecules and microenvironments. Exploring these resistance mechanisms will improve the therapeutic efficacy of bortezomib. In this study, bone marrow tissues from three patients with MM, both sensitive and resistant to bortezomib, were collected for circRNA high-throughput sequencing analysis. The relationship between circ_0000337, miR-98-5p, and target gene DNA2 was analyzed by luciferase detection and verified by RT-qPCR. We first found that circ_0000337 was significantly upregulated in bortezomib-resistant MM tissues and cells, and overexpression of circ_0000337 could promote bortezomib resistance in MM cells. circ_0000337 may act as a miR-98-5p sponge to upregulate DNA2 expression, regulate DNA damage repair, and induce bortezomib resistance. Furthermore, it was determined that the increased circ_0000337 level in bortezomib-resistant cells was due to an increased N6-methyladenosine (m6A) level, resulting in enhanced RNA stability. In conclusion, the m6A level of circ_0000337 and its regulation may be a new and potential therapeutic target for overcoming bortezomib resistance in MM.
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Iron metabolism is involved in the development and drug resistance of many malignancies, including multiple myeloma (MM). Based on recent studies on iron metabolism and MM, this paper reviews the relationship between iron metabolism and disease process of MM in terms of iron overload leading to ferroptosis in MM cells, the role of iron deficiency in oxidative respiration and proliferation of MM cells, and the interaction between ferroptosis and autophagy in the disease process. The mechanisms by which iron metabolism-related substances lead to MM cells' resistance to proteasome inhibitors (PI) through inducing redox imbalance and M2 macrophage polarization are also briefly described, aiming to provide a theoretical basis for the application of iron metabolism-related drugs to the clinical treatment of MM patients.
Asunto(s)
Resistencia a Antineoplásicos , Hierro , Mieloma Múltiple , Humanos , Autofagia , Progresión de la Enfermedad , Hierro/metabolismoRESUMEN
Multiple myeloma (MM) is characterized by excessive aggregation of B-cell-derived malignant plasma cells in the hematopoietic system of bone marrow. Previously, we synthesized an innovative molecule named dihydrocelastrol (DHCE) from celastrol, a triterpene purified from medicinal plant Tripterygium wilfordii. Herein, we explore the therapeutic properties and latent signal transduction mechanism of DHCE action in bortezomib (BTZ)-resistant (BTZ-R) MM cells. In this study, we first report that DHCE shows antitumor activities in vitro and in vivo and exerts stronger inhibitory effects than celastrol on BTZ-R cells. We find that DHCE inhibits BTZ-R cell viability by promoting apoptosis via extrinsic and intrinsic pathways and suppresses BTZ-R MM cell proliferation by inducing G0/G1 phase cell cycle arrest. In addition, inactivation of JAK2/STAT3 and PI3K/Akt pathways are involved in the DHCE-mediated antitumor effect. Simultaneously, DHCE acts synergistically with BTZ on BTZ-R cells. PSMB5, a molecular target of BTZ, is overexpressed in BTZ-R MM cells compared with BTZ-S MM cells and is demonstrated to be a target of STAT3. Moreover, DHCE downregulates PSMB5 overexpression in BTZ-R MM cells, which illustrates that DHCE overcomes BTZ resistance through increasing the sensitivity of BTZ in resistant MM via inhibiting STAT3-dependent PSMB5 regulation. Overall, our findings imply that DHCE may become a potential therapeutic option that warrants clinical evaluation for BTZ-R MM.
Asunto(s)
Antineoplásicos , Mieloma Múltiple , Humanos , Bortezomib/farmacología , Bortezomib/metabolismo , Bortezomib/uso terapéutico , Mieloma Múltiple/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Apoptosis , Proliferación Celular , Complejo de la Endopetidasa Proteasomal/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismoRESUMEN
While 19S proteasome regulatory particle (RP) inhibition is a promising new avenue for treating bortezomib-resistant myeloma, the anti-tumor impact of inhibiting 19S RP component PSMD14 could not be explained by a selective inhibition of proteasomal activity. Here, we report that PSMD14 interacts with NSD2 on chromatin, independent of 19S RP. Functionally, PSMD14 acts as a histone H2AK119 deubiquitinase, facilitating NSD2-directed H3K36 dimethylation. Integrative genomic and epigenomic analyses revealed the functional coordination of PSMD14 and NSD2 in transcriptional activation of target genes (e.g., RELA) linked to myelomagenesis. Reciprocally, RELA transactivates PSMD14, forming a PSMD14/NSD2-RELA positive feedback loop. Remarkably, PSMD14 inhibitors enhance bortezomib sensitivity and fosters anti-myeloma synergy. PSMD14 expression is elevated in myeloma and inversely correlated with overall survival. Our study uncovers an unappreciated function of PSMD14 as an epigenetic regulator and a myeloma driver, supporting the pursuit of PSMD14 as a therapeutic target to overcome the treatment limitation of myeloma.
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Histonas , Mieloma Múltiple , Humanos , Histonas/genética , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Bortezomib/farmacología , Bortezomib/metabolismo , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/patología , Línea Celular Tumoral , Enzimas Desubicuitinizantes/metabolismo , Inhibidores de Proteasoma/farmacología , Transactivadores/metabolismoRESUMEN
Bortezomib, an FDA approved drug in 2003 for newly diagnosed and relapsed/refractory MM, had showed great efficacy in different clinical settings. However, many patients still developed resistance to Bortezomib, and the mechanism of action remains unelucidated. Here, we showed that Bortezomib resistance can be partially overcome by targeting a different subunit of 20 S complex - PSMB6. PSMB6 knock down by shRNA increased sensitivity to Bortezomib in resistant and sensitive cell line. Interestingly, a STAT3 inhibitor, Stattic, is shown to selectively inhibit PSMB6 and induce apoptosis in Bortezomib resistant and sensitive MM cells, even with IL-6 induction. Therefore, PSMB6 is a novel target for Bortezomib resistance and Stattic may offer a potential therapeutic strategy.
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Antineoplásicos , Mieloma Múltiple , Humanos , Bortezomib/farmacología , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Apoptosis/genética , Línea Celular Tumoral , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismoRESUMEN
Multiple myeloma (MM) is an incurable condition and the second most common hematological malignancy. Over the past few years, there has been progress in the treatment of MM, but most patients still relapse. Multiple myeloma stem-like cells (MMSCs) are believed to be the main reason for drug resistance and eventual relapse. Currently, there are not enough therapeutic agents that have been identified for eradication of MMSCs, and thus, identification of the same may alleviate the issue of relapse in patients. In the present study, we showed that luteolin (LUT), a natural compound obtained from different plants, such as vegetables, medicinal herbs, and fruits, effectively inhibits the proliferation of MM cells and overcomes bortezomib (BTZ) resistance in them in vitro and in vivo, mainly by decreasing the proportion of ALDH1+ cells. Furthermore, RNA sequencing after LUT treatment of MM cell lines and an MM xenograft mouse model revealed that the effects of the compound are mediated through inhibition of transforming growth factor-ß signaling. Similarly, we found that LUT also significantly reduced the proportion of ALDH1+ cells in primary CD138+ plasma cells. In addition, LUT could overcome the BTZ treatment-induced increase in the proportion of ALDH1+ cells, and the combination of LUT and BTZ had a synergistic effect against myeloma cells. Collectively, our findings suggested that LUT is a promising agent that manifests MMSCs to overcome BTZ resistance, alone or in combination with BTZ, and thus, is a potential therapeutic drug for the treatment of MM.
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Antineoplásicos , Mieloma Múltiple , Humanos , Animales , Ratones , Bortezomib/farmacología , Mieloma Múltiple/patología , Luteolina/farmacología , Resistencia a Antineoplásicos , Apoptosis , Línea Celular Tumoral , Recurrencia Local de Neoplasia/tratamiento farmacológico , Transducción de Señal , Factor de Crecimiento Transformador beta/farmacología , Antineoplásicos/farmacologíaRESUMEN
BACKGROUND: The proteasome inhibitor bortezomib (BTZ) has significantly improved the survival of multiple myeloma (MM) patients. However, most MM patients still relapse and have drug resistance after BTZ treatment. METHODS: siRNA transfection was performed to knock down BDNF and TrkB expression. ELISA, western blot, quantitative polymerase chain reaction, CCK-8 assay, and flow cytometry analysis were performed to analyze the functions of BDNF/TrkB signaling in MM cells. RESULTS: We identified a cell-autonomous mechanism that promotes BTZ resistance in MM, prolongs their RPMI 8226/BTZ resistant cell survival and optimizes their proliferating function. Specifically, RPMI 8226/BTZ cells produced the brain derived neurotrophic factor (BDNF) and its receptor TrkB, which served as a survival factor in the RPMI 8226/BTZ resistant environment. BDNF/TrkB induced phosphorylation of STAT3 that upregulated the bone morphogenetic protein/retinoic acid inducible neural-specific 3 (BRINP3). CONCLUSIONS: BDNF/TrkB enhanced downstream pathway expression of phosphorylation STAT3 and BRINP3 molecules, promoting RPMI 8226/BTZ cell proliferation and survival. GENERAL SIGNIFICANCE: These data place BDNF/TrkB at the top of a pSTAT3-BRINP3 survival pathway and link adaptability to BTZ resistant conditions in MM disease.
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Mieloma Múltiple , Humanos , Bortezomib/farmacología , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Factor Neurotrófico Derivado del Encéfalo , Línea Celular Tumoral , Inhibidores de Proteasoma/farmacologíaRESUMEN
Iron metabolism is involved in the development and drug resistance of many malignancies, including multiple myeloma (MM). Based on recent studies on iron metabolism and MM, this paper reviews the relationship between iron metabolism and disease process of MM in terms of iron overload leading to ferroptosis in MM cells, the role of iron deficiency in oxidative respiration and proliferation of MM cells, and the interaction between ferroptosis and autophagy in the disease process. The mechanisms by which iron metabolism-related substances lead to MM cells' resistance to proteasome inhibitors (PI) through inducing redox imbalance and M2 macrophage polarization are also briefly described, aiming to provide a theoretical basis for the application of iron metabolism-related drugs to the clinical treatment of MM patients.
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Humanos , Autofagia , Progresión de la Enfermedad , Hierro/metabolismo , Mieloma Múltiple , Resistencia a AntineoplásicosRESUMEN
Mantle cell lymphoma (MCL) is an aggressive non-Hodgkin lymphoma with poor prognosis, due to the inevitable development of drug resistance. Despite being the first-in-class proteasome inhibitor for relapsed/refractory MCL, resistance to bortezomib (BTZ) in MCL patients remains a major hurdle of effective therapy, and relapse following BTZ is frequent. Understanding the mechanisms underlying BTZ resistance is, therefore, important for improving the clinical outcome and developing novel therapeutic strategies. Here, we established de novo BTZ-resistant human MCL-derived cells with the highest resistance index of 300-fold compared to parental cells. We provided compelling evidence that both Bcl-xL and Bax are key mediators in determining BTZ sensitivity in MCL cells. Overexpression of antiapoptotic Bcl-xL and depletion of proapoptotic Bax cooperatively protected MCL cells against BTZ-induced apoptosis, causing acquired BTZ resistance, likely by tilting the balance of Bcl-2 family proteins toward antiapoptotic signaling. Bioinformatics analyses suggested that high BCL2L1 (encoded Bcl-xL) and low BAX were, in part, associated with poor prognosis of MCL patients, e.g., when combined with low OGT, which regulates cellular O-GlcNAcylation. Our findings support recent strategies in small molecule drug discovery co-targeting antiapoptotic Bcl-2 family proteins using BH3 mimetics and Bax using Bax activators to overcome cancer drug resistance.
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Linfoma de Células del Manto , Humanos , Adulto , Bortezomib/farmacología , Bortezomib/uso terapéutico , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/genética , Linfoma de Células del Manto/patología , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Línea Celular Tumoral , Recurrencia Local de Neoplasia , Proteínas Proto-Oncogénicas c-bcl-2/metabolismoRESUMEN
Multiple myeloma (MM) remains an incurable hematologic malignancy due to its frequent drug resistance and relapse. Cluster of Differentiation 47 (CD47) is reported to be highly expressed on MM cells, suggesting that the blockade of CD47 signaling pathway could be a potential therapeutic candidate for MM. In this study, we developed a bortezomib-resistant myeloma patient-derived xenograft (PDX) from an extramedullary pleural effusion myeloma patient sample. Notably, anti-CD47 antibody treatments significantly inhibited tumor growth not only in MM cell line-derived models, including MM.1S and NCI-H929, but also in the bortezomib-resistant MM PDX model. Flow cytometric data showed that anti-CD47 therapy promoted the polarization of tumor-associated macrophages from an M2- to an M1-like phenotype. In addition, anti-CD47 therapy decreased the expression of pro-angiogenic factors, increased the expression of anti-angiogenic factors, and improved tumor vascular function, suggesting that anti-CD47 therapy induces tumor vascular normalization. Taken together, these data show that anti-CD47 antibody therapy reconditions the tumor immune microenvironment and inhibits the tumor growth of bortezomib-resistant myeloma PDX. Our findings suggest that CD47 is a potential new target to treat bortezomib-resistant MM.
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Mieloma Múltiple , Animales , Humanos , Bortezomib/farmacología , Bortezomib/uso terapéutico , Mieloma Múltiple/patología , Xenoinjertos , Recurrencia Local de Neoplasia , Microambiente Tumoral , Modelos Animales de Enfermedad , Línea Celular Tumoral , Resistencia a Antineoplásicos , ApoptosisRESUMEN
Multiple myeloma is a plasma cell malignancy, accounting for approximately 1% of new cancer cases. It is the second most common hematological malignancy. Novel clinical agents such as the proteasome inhibitor-bortezomib, have shown improved survival rates in recent decades. However, multiple myeloma remains incurable, as most patients eventually relapse and become refractory to current treatments. Therefore, there is an urgent need for developing new regimens to overcome the bortezomib resistance. Here, we screened a library of 2370 bioactives and found that polyphyllin VII selectively suppressed multiple myeloma cell growth in vitro and in vivo. We identified moesin, one of the critical regulators of the Wnt/ß-catenin pathway, as a target of polyphyllin VII by drug affinity responsive target stability assay and cellular thermal shift assay. Polyphyllin VII binds to moesin and induces its degradation via the ubiquitin-proteasome pathway, thereby impairing the Wnt/ß-catenin pathway activity and leading to a reduction in the side population cells to overcome bortezomib resistance. Our study identified polyphyllin VII as a promising compound and moesin as a potential diagnostic and therapeutic target for treating multiple myeloma.
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Antineoplásicos , Mieloma Múltiple , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Bortezomib/farmacología , Bortezomib/uso terapéutico , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Proteínas de Microfilamentos , Mieloma Múltiple/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Inhibidores de Proteasoma/farmacología , Inhibidores de Proteasoma/uso terapéutico , Saponinas , beta Catenina/metabolismoRESUMEN
OBJECTIVE: This study investigated the mechanism by which miR-197-3p regulated IL-6 expression and reduced bortezomib (BTZ) resistance in multiple myeloma (MM). METHODS: The expression of miR-197-3p, MEAF6 and IL-6 in BTZ-resistant MM cells was measured. The effects of miR-197-3p/IL-6 axis on drug resistance and cell apoptosis were evaluated in BTZ-resistant MM cells. The expression of JAK/STAT3 proteins was detected by Western blotting. The binding of miR-197-3p to MEAF6 mRNA was verified using molecular biology techniques. Chromatin immunoprecipitation was used to assess histone acetylation in IL-6 promoter. The effect of miR-197-3p on MM growth was investigated in a mouse model. RESULTS: MiR-197-3p was lowly expressed, and MEAF6 and IL-6 were highly expressed in BTZ-resistant MM cells. Overexpression of miR-197-3p increased drug sensitivity in BTZ-resistant MM cells, which was counteracted by overexpression of IL-6. Overexpression of miR-197-3p also inhibited MM growth in vivo. Mechanistically, miR-197-3p suppressed the expression of IL-6 by inhibiting MEAF6-mediated histone H3 acetylation in IL-6 promoter. The miR-197-3p/IL-6 axis also inhibited the activation of JAK/STAT3 signaling pathway. CONCLUSION: miR-197-3p reduces BTZ resistance in MM by inhibiting acetylation-mediated expression of IL-6 and by inactivating JAK/STAT3 signaling pathway.
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Bortezomib , Resistencia a Antineoplásicos , Histona Acetiltransferasas , MicroARNs , Mieloma Múltiple , Animales , Antineoplásicos/farmacología , Apoptosis , Bortezomib/farmacología , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos/genética , Histona Acetiltransferasas/genética , Humanos , Interleucina-6/genética , Ratones , MicroARNs/genética , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genéticaRESUMEN
AIM: Multiple myeloma (MM) is a hematological malignancy of antibody-producing mature B cells or plasma cells. The proteasome inhibitor, bortezomib, was the first-in-class compound to be FDA approved for MM and is frequently utilized in induction therapy. However, bortezomib refractory disease is a major clinical concern, and the efficacy of the pan-histone deacetylase inhibitor (HDACi), panobinostat, in bortezomib refractory disease indicates that HDAC targeting is a viable strategy. Here, we utilized isogenic bortezomib resistant models to profile HDAC expression and define baseline and HDACi-induced expression patterns of individual HDAC family members in sensitive vs. resistant cells to better understanding the potential for targeting these enzymes. METHODS: Gene expression of HDAC family members in two sets of isogenic bortezomib sensitive or resistant myeloma cell lines was examined. These cell lines were subsequently treated with HDAC inhibitors: panobinostat or vorinostat, and HDAC expression was evaluated. CRISPR/Cas9 knockdown and pharmacological inhibition of specific HDAC family members were conducted. RESULTS: Interestingly, HDAC6 and HDAC7 were significantly upregulated and downregulated, respectively, in bortezomib-resistant cells. Panobinostat was effective at inducing cell death in these lines and modulated HDAC expression in cell lines and patient samples. Knockdown of HDAC7 inhibited cell growth while pharmacologically inhibiting HDAC6 augmented cell death by panobinostat. CONCLUSION: Our data revealed heterogeneous expression of individual HDACs in bortezomib sensitive vs. resistant isogenic cell lines and patient samples treated with panobinostat. Cumulatively our findings highlight distinct roles for HDAC6 and HDAC7 in regulating cell death in the context of bortezomib resistance.
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Although multiple myeloma (MM) patients benefit from standard bortezomib (BTZ) chemotherapy, they develop drug resistance, resulting in relapse. We investigated whether histone deacetylase 6 (HDAC6) inhibitor A452 overcomes bortezomib resistance in MM. We show that HDAC6-selective inhibitor A452 significantly decreases the activation of BTZ-resistant markers, such as extracellular signal-regulated kinases (ERK) and nuclear factor kappa B (NF-κB), in acquired BTZ-resistant MM cells. Combination treatment of A452 and BTZ or carfilzomib (CFZ) synergistically reduces BTZ-resistant markers. Additionally, A452 synergizes with BTZ or CFZ to inhibit the activation of NF-κB and signal transducer and activator of transcription 3 (STAT3), resulting in decreased expressions of low-molecular-mass polypeptide 2 (LMP2) and LMP7. Furthermore, combining A452 with BTZ or CFZ leads to synergistic cancer cell growth inhibition, viability decreases, and apoptosis induction in the BTZ-resistant MM cells. Overall, the synergistic effect of A452 with CFZ is more potent than that of A452 with BTZ in BTZ-resistant U266 cells. Thus, our findings reveal the HDAC6-selective inhibitor as a promising therapy for BTZ-chemoresistant MM.
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Antineoplásicos/farmacología , Derivados del Benceno/farmacología , Bortezomib/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Mieloma Múltiple/tratamiento farmacológico , Línea Celular Tumoral , Histona Desacetilasa 6/antagonistas & inhibidores , Histona Desacetilasa 6/metabolismo , Humanos , Mieloma Múltiple/metabolismoRESUMEN
Multiple myeloma (MM) is a malignant neoplasm featured by obvious drug resistance and poor prognosis. MicroRNAs (miRNAs) are a class of small noncoding RNAs with crucial roles in many biological processes including cancer initiation and progression. The current study aims to investigate the pathogenic role and molecular mechanism of miRNAs in MM drug resistance. In the present study, The expression profile of miRNAs in MM samples was analyzed by microarray and real-time polymerase chain reaction. Protein expressions were detected by Western blot analysis. Cell apoptosis was detected by the Annexin V staining assay. The interaction between miRNA and the targeting mRNA was assessed using Dual luciferase reporter assay. Herein, we show that expression profile of miRNAs is deregulated in MM. miR-218, one of the most aberrational miRNAs in MM, is significantly decreased in MM cells compared to peripheral blood mononuclear cell (PBMC). Genetic manipulation reveals miR-218 control the response of MM cells to anticancer drug bortezomib (BTZ). Overexpression of miR-218 causes a significant aberrant genes expression including leucine rich repeat containing 28 (LRRC28). Mechanistic study shows that miR-218 control the drug response through mediating the expression of LRRC28 in MM cells. Overexpression of LRRC28 significantly reserves miR-218-mediated cell response to BTZ. Taken together, miR-218 is decreased in MM that contributes to BTZ resistance via targeting LRRC28, which might be used as a novel therapeutic target for multiple myeloma.
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Antineoplásicos/farmacología , Bortezomib/farmacología , MicroARNs/metabolismo , Adulto , Western Blotting , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Masculino , MicroARNs/genéticaRESUMEN
The bone marrow microenvironment plays an essential role in multiple myeloma (MM) progression. We aimed to explore the alterations of levels of long noncoding RNAs and messenger RNAs (mRNAs), derived from exosomes in peripheral blood, in resistance to bortezomib (Btz) of MM patients. Peripheral blood samples were collected from five Btz-resistant and five Btz-sensitive MM patients. Exosomes in patients' peripheral blood were enriched, and the profiles of long noncoding RNAs (lncRNAs) and mRNAs in exosomes were determined using deep sequencing. Bioinformatics analysis was performed to explore biological function. MTS was employed to determine the viability of Roswell Park Memorial Institute (RPMI) 8226 and LP-1 cells incubated with exosomes derived from Btz-resistant patients. Quantitative polymerase chain reaction (qPCR) was used to evaluate the levels of exosomal FFAR1, SP9, HIST1H2BG, and ITIH2. Incubation with Btz-resistant patient-derived exosomes significantly increased the viability of Btz-treated RPMI 8226 and LP-1 cells in a dose-dependent manner. We identified 482 lncRNAs and 2099 mRNAs deregulated in exosomes of the Btz-resistance group; and 78 mRNAs were enriched in DR-related pathways, including mammalian target of rapamycin, platinum drug resistance, and the cAMP and phosphoinositide 3-kinase-Akt signaling pathways. qPCR results verified the increases in FFAR1 and SP9 and decreases in HIST1H2BG and ITIH2 in Btz-resistant patient-derived exosomes. Moreover, exosomal FFAR1 and SP9 exhibited potential as independent prognostic indicators of survival of MM patients. Our study reveals significant dysregulation of exosomal RNA components in the Btz-resistant group of MM patients as well as several mRNAs that may be used as biomarkers of prognosis of MM patients that are resistant to Btz.
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Bortezomib/farmacología , Exosomas/genética , Mieloma Múltiple/genética , Médula Ósea/metabolismo , Bortezomib/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Resistencia a Antineoplásicos/genética , Femenino , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Invasividad Neoplásica/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal/genética , Transcriptoma/genética , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/genéticaRESUMEN
BACKGROUND: Chemoresistance remains a major treatment obstacle in multiple myeloma (MM). Novel new therapies are thus in need. Transient Receptor Potential Vanilloid type 1 (TRPV1) is a calcium-permeable ion channel that has been demonstrated to be expressed in solid tumors. Calcium channels have been shown to be involved in the regulation of cell proliferation, chemoresistance, migration and invasion. The aim of the current study was to evaluate its possible role in MM. METHODS: Pharmacological inhibitor was used to evaluate the role of TRPV1 in MM cell lines and primary MM cells. Flow cytometry, molecular analysis, fluorescent microscopy, proteomic analysis and xenograft in vivo model of MM with BM involvement were employed to assess the effect of TRPV1 inhibition and decipher its unique mechanism of action in MM. RESULTS: TRPV1 was found to be expressed by MM cell lines and primary MM cells. TRPV1 inhibition using the antagonist AMG9810-induced MM cell apoptosis and synergized with bortezomib, overcoming both CXCR4-dependent stroma-mediated and acquired resistance. In accordance, AMG9810 suppressed the expression and activation of CXCR4 in MM cells. TRPV1 inhibition increased mitochondrial calcium levels with subsequent mitochondrial ROS accumulation and depolarization. These effects were reversed by calcium chelation, suggesting the role of calcium perturbations in oxidative stress and mitochondrial destabilization. Furthermore, AMG9810 abolished bortezomib-induced accumulation of mitochondrial HSP70 and suppressed protective mitochondrial unfolded protein response. Proteomics revealed unique molecular signature related to the modification of ubiquitin signaling pathway. Consequently, 38 proteins related to the ubiquitylation machinery were downregulated upon combined bortezomib/AMG9810 treatment. Concomitantly, AMG9810 abolished bortezomib-induced ubiquitination of cytosolic and mitochondrial proteins. Furthermore, bortezomib/AMG9810 treatment induced mitochondrial accumulation of PINK1, significantly reduced the mitochondrial mass and promoted mitochondrial-lysosomal fusion, indicating massive mitophagy. Finally, in a recently developed xenograft model of systemic MM with BM involvement, bortezomib/AMG9810 treatment effectively reduced tumor burden in the BM of MM-bearing mice. CONCLUSIONS: Altogether, our results unravel the mechanism mediating the strong synergistic anti-MM activity of bortezomib in combination with TRPV1 inhibition which may be translated into the clinic.
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Acrilamidas/farmacología , Antineoplásicos/farmacología , Bortezomib/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Mitofagia/efectos de los fármacos , Mieloma Múltiple/tratamiento farmacológico , Canales Catiónicos TRPV/antagonistas & inhibidores , Acrilamidas/uso terapéutico , Animales , Antineoplásicos/uso terapéutico , Bortezomib/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Calcio/metabolismo , Línea Celular Tumoral , Humanos , Ratones , Mieloma Múltiple/metabolismo , Canales Catiónicos TRPV/metabolismo , Ubiquitina/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacosRESUMEN
Objective: To explore the role of cell division cycle protein 37 (Cdc37) mediating bortezomib (BTZ) resistance in multiple myeloma (MM) via the regulation of autophagy activity to provide a novel strategy for MM therapy. Methods: The expressions of Cdc37 and LC3b were investigated in BTZ-resistant MM cell line ANBL-6.BR using quantitative real-time PCR (qRT-PCR) and western blot (WB) analysis. Cdc37 was upregulated in ANBL-6.BR cells owing to lentivirus transfection. The LC3b expression was detected with WB, and BTZ-induced apoptosis was explored using flow cytometry. Cdc37 was then down-regulated by shRNA in the MM cell line NCI-H929. Sensitivity of BTZ was evaluated using CCK-8 analysis. WB analysis was performed to check the expression of the AKT/mTOR pathway and autophagy-associated proteins. The sensitivity of NCI-H929 cells to BTZ in the presence of autophagy inhibitor chloroquine (CQ) was analyzed using flow cytometry. Results: Cdc37 was down-regulated, while autophagy-associated gene LC3b was upregulated in BTZ-resistant cell line ANBL-6.BR. Up-regulated Cdc37 in ANBL-6.BR cells could inhibit LC3b expression and increase the sensitivity of MM to BTZ. Suppressing Cdc37 expression in MM cell line NCI-H929 induced BTZ resistance and autophagy activation, while CQ could rescue BTZ resistance caused by Cdc37 inhibition. Conclusion: Cdc37 may participate in BTZ resistance in MM via the regulation of autophagy activity.
Asunto(s)
Autofagia , Mieloma Múltiple , Antineoplásicos , Apoptosis , Bortezomib , Proteínas de Ciclo Celular , Línea Celular Tumoral , Chaperoninas , Resistencia a Antineoplásicos , HumanosRESUMEN
Multiple myeloma (MM) is a B-cell malignancy requiring inflammatory microenvironment signals for cell survival and proliferation. Despite improvements in pharmacological tools, MM remains incurable mainly because of drug resistance. The present study aimed to investigate the implication of Toll-like receptor 4 (TLR4) as the potential mechanism of bortezomib (BTZ) resistance. We found that TLR4 activation induced mitochondrial biogenesis and increased mitochondrial mass in human MM cell lines. Moreover, TLR4 signaling was activated after BTZ exposure and was increased in BTZ-resistant U266 (U266-R) cells. A combination of BTZ with TAK-242, a selective TLR4 inhibitor, overcame drug resistance through the generation of higher and extended oxidative stress, strong mitochondrial depolarization and severe impairment of mitochondrial fitness which in turn caused cell energy crisis and activated mitophagy and apoptosis. We further confirmed the efficacy of a TAK-242/BTZ combination in plasma cells from refractory myeloma patients. Consistently, inhibition of TLR4 increased BTZ-induced mitochondrial depolarization, restoring pharmacological response. Taken together, these findings indicate that TLR4 signaling acts as a stress-responsive mechanism protecting mitochondria during BTZ exposure, sustaining mitochondrial metabolism and promoting drug resistance. Inhibition of TLR4 could be therefore be a possible target in patients with refractory MM to overcome BTZ resistance.
RESUMEN
Background: Nowadays, microRNAs (miRNAs) attract much attention in regulating anticancer drug resistance in cancers including multiple myeloma (MM). Bortezomib is the first-line choice in MM treatment, and bortezomib resistance caused by aberrant DNA repair leads to the recurrence and therapeutic failure of MM. Objective: Our study aims to identify a miRNA that overcomes bortezomib resistance in MM. Methods: We established bortezomib-resistant MM cell lines, and screened several miRNAs that have aberrant expressions in MM cell lines. The expression of DNA-repair-related proteins were assessed by western blot, and cell viability was determined by the MTT assay in bortezomib-resistant cell lines. The binding between miRNAs and 3'-UTR of APE1 mRNA was confirmed by luciferase reporter assay. The mouse bortezomib-resistant xenograft was established to verify the therapeutic effect of miRNA overexpression. Results: miR-520g and miR-520h were significantly downregulated in bortezomib-resistant MM cell lines, and overexpression of miR-520g and miR-520h together inhibited expression of homologous recombination-related protein Rad51 and cell viability of bortezomib-resistant MM cells in vitro by binding with 3'-UTR of APE1 mRNA. Combined overexpression of miR-520g and miR-520h inhibited bortezomib-resistant MM tumor growth in vivo. Conclusion: Our findings demonstrated that combined overexpression of miR-520g and miR-520h overcomes bortezomib resistance in MM through inhibition of DNA repair, offering a promising therapeutic target for MM treatment.