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1.
Apoptosis ; 29(3-4): 412-423, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38001343

ABSTRACT

Ferroptosis, a nonapoptotic form of cell death marked by iron-dependent peroxidation of phospholipids, is associated with the occurrence and progression of tumors. Erastin, a selective inhibitor of the cystine/glutamate transporter system Xc-, can induce the ferroptosis of cancer cells. Multiple myeloma (MM) has been reported to be insensitive to erastin-induced ferroptosis. However, we found the erastin sensitivity of different MM cells varied widely. Specifically, SLC7A11 abundance determined the sensitivity of MM cells to erastin-induced ferroptosis. MM cells expressing a high SLC7A11 level were more sensitive to erastin-induced ferroptosis than cells expressing a low level of SLC7A11. Moreover, the expression of SLC7A11 gradually increased with the progression of plasma cell dyscrasias. Survival analysis indicated that high levels of SLC7A11 predicted a poor prognosis for MM patients. Knocking down SLC7A11 expression significantly inhibited the proliferation of MM cells and induced ferroptotic cell death. Additionally, we revealed that the long noncoding RNA (lncRNA) SLC7A11-AS1 was a critical regulatory factor of SLC7A11 expression. SLC7A11-AS1 overexpression diminished SLC7A11 levels, leading to the ferroptosis of MM cells. In summary, our data show that heterogeneous SLC7A11 expression affects MM cell sensitivity to ferroptosis, providing a theoretical basis for improving the clinical treatment of MM.


Subject(s)
Ferroptosis , Multiple Myeloma , Piperazines , Humans , Apoptosis/genetics , Multiple Myeloma/drug therapy , Multiple Myeloma/genetics , Ferroptosis/genetics , Cell Death , Amino Acid Transport System y+/genetics , Amino Acid Transport System y+/metabolism
2.
Ann Hematol ; 103(8): 2905-2915, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38424303

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is the most common and aggressive type of B-cell lymphoma. Unfortunately, about one-third of patients either relapse after the initial treatment or are refractory to first-line therapy, indicating a need for new treatment modalities. PIM serine/threonine kinases are proteins that are associated with genetic mutations, overexpression, or translocation events in B-cell lymphomas. We conducted an integrative analysis of whole-exome sequencing in 52 DLBCL patients, and no amplification, mutation, or translocation of the PIM1 gene was detected. Instead, analyses of TCGA and GTEx databases identified that PIM1 expression was increased in DLBCL samples compared to normal tissue, and high expression levels were associated with poor overall survival. Moreover, interference of PIM1 significantly suppressed DLBCL cell proliferation. In addition, we identified anwulignan, a natural small-molecule compound, as a PIM1 inhibitor. Anwulignan directly binds to PIM1 and exerts antitumor effects on DLBCL in vitro and in vivo by inducing apoptosis, cell cycle arrest, and autophagic cell death. Furthermore, we identified an effective synergistic combination between anwulignan and chidamide. Our findings suggested that PIM1 could be a therapeutic target and prognostic factor for DLBCL, and anwulignan holds promise for future development as a natural product for treatment.


Subject(s)
Lymphoma, Large B-Cell, Diffuse , Proto-Oncogene Proteins c-pim-1 , Humans , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , Proto-Oncogene Proteins c-pim-1/genetics , Proto-Oncogene Proteins c-pim-1/metabolism , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/genetics , Mice , Animals , Biological Products/therapeutic use , Cell Line, Tumor , Female , Xenograft Model Antitumor Assays , Male , Apoptosis/drug effects , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacology , Cell Proliferation/drug effects , Aminopyridines/therapeutic use , Aminopyridines/pharmacology , Molecular Targeted Therapy , Gene Expression Regulation, Neoplastic/drug effects
3.
Br J Cancer ; 128(6): 1086-1094, 2023 04.
Article in English | MEDLINE | ID: mdl-36593359

ABSTRACT

BACKGROUND: Dysregulation of alternative splicing (AS) triggers many tumours, understanding the roles of splicing events during tumorigenesis would open new avenues for therapies and prognosis in multiple myeloma (MM). METHODS: Molecular, genetic, bioinformatic and statistic approaches are used to determine the mechanism of the candidate splicing factor (SF) in myeloma cell lines, myeloma xenograft models and MM patient samples. RESULTS: GSEA reveals a significant difference in the expression pattern of the alternative splicing pathway genes, notably enriched in MM patients. Upregulation of the splicing factor SRSF1 is observed in the progression of plasma cell dyscrasias and predicts MM patients' poor prognosis. The c-indices of the Cox model indicated that SRSF1 improved the prognostic stratification of MM patients. Moreover, SRSF1 knockdown exerts a broad anti-myeloma activity in vitro and in vivo. The upregulation of SRSF1 is caused by the transcription factor YY1, which also functions as an oncogene in myeloma cells. Through RNA-Seq, we systematically verify that SRSF1 promotes the tumorigenesis of myeloma cells by switching AS events. CONCLUSION: Our results emphasise the importance of AS for promoting tumorigenesis of MM. The candidate SF might be considered as a valuable therapeutic target and a potential prognostic biomarker for MM.


Subject(s)
Alternative Splicing , Multiple Myeloma , Humans , Serine-Arginine Splicing Factors/genetics , Serine-Arginine Splicing Factors/metabolism , RNA Splicing Factors/genetics , RNA Splicing Factors/metabolism , Cell Transformation, Neoplastic , Carcinogenesis
4.
Blood ; 137(12): 1603-1614, 2021 03 25.
Article in English | MEDLINE | ID: mdl-32967010

ABSTRACT

The initiation and progression of diffuse large B-cell lymphoma (DLBCL) is governed by genetic and epigenetic aberrations. As the most abundant eukaryotic messenger RNA (mRNA) modification, N6-methyladenosine (m6A) is known to influence various fundamental bioprocesses by regulating the target gene; however, the function of m6A modifications in DLBCL is unclear. PIWI-interacting RNAs (piRNAs) have been indicated to be epigenetic effectors in cancer. Here, we show that high expression of piRNA-30473 supports the aggressive phenotype of DLBCL, and piRNA-30473 depletion decreases proliferation and induces cell cycle arrest in DLBCL cells. In xenograft DLBCL models, piRNA-30473 inhibition reduces tumor growth. Moreover, piRNA-30473 is significantly associated with overall survival in a univariate analysis and is statistically significant after adjusting for the National Comprehensive Cancer Network-International Prognostic Index in the multivariate analysis. Additional studies demonstrate that piRNA-30473 exerts its oncogenic role through a mechanism involving the upregulation of WTAP, an m6A mRNA methylase, and thus enhances the global m6A level. Integrating transcriptome and m6A-sequencing analyses reveals that WTAP increases the expression of its critical target gene, hexokinase 2 (HK2), by enhancing the HK2 m6A level, thereby promoting the progression of DLBCL. Together, the piRNA-30473/WTAP/HK2 axis contributes to tumorigenesis by regulating m6A RNA methylation in DLBCL. Furthermore, by comprehensively analyzing our clinical data and data sets, we discover that the m6A regulatory genes piRNA-30473 and WTAP improve survival prediction in DLBCL patients. Our study highlights the functional importance of the m6A modification in DLBCL and might assist in the development of a prognostic stratification and therapeutic approach for DLBCL.


Subject(s)
Carcinogenesis/genetics , Gene Expression Regulation, Neoplastic , Lymphoma, Large B-Cell, Diffuse/genetics , RNA, Small Interfering/genetics , Epigenesis, Genetic , Humans , Lymphoma, Large B-Cell, Diffuse/diagnosis , Methyltransferases/genetics , Prognosis , RNA, Messenger/genetics
5.
Nanotechnology ; 34(13)2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36584386

ABSTRACT

We report on the spin-to-charge conversion (SCC) in Mo0.25W0.75Te2-x(MWT)/Y3Fe5O12(YIG) heterostructures at room temperature. The centimeter-scale amorphous MWT films are deposited on liquid-phase-epitaxial YIG by pulsed laser deposition technique. The significant SCC voltage is measured in the MWT layer with a sizable spin Hall angle of ∼0.021 by spin pumping experiments. The control experiments by inserting MgO or Ag layer between MWT and YIG show that the SCC is mainly attributed to the inverse spin Hall effect rather than the thermal or interfacial Rashba effect. Our work provides a novel spin-source material for energy-efficient topological spintronic devices.

6.
Carcinogenesis ; 43(11): 1050-1058, 2022 12 25.
Article in English | MEDLINE | ID: mdl-36170154

ABSTRACT

Ferroptosis is a non-apoptotic form of cell death caused by excessive iron exposure. The role played by the ferroptosis-related genes and pathways in multiple myeloma (MM) is poorly understood. Here, we show that the ferroptosis-related pathways might be involved in tumorigenesis and are closely correlated with the prognosis of MM. The ferroptosis suppressor genes are progressively enriched with the progression of plasma cell dyscrasias. Furthermore, high expression of ferroptosis suppressor genes is correlated with high International Staging System and Revised-ISS staging of MM, as well as the poor outcomes of poor outcomes in progression-free survival and overall survival . The ferroptosis driver genes and the ferroptosis suppressor genes have the opposite effects on the progression and prognosis of MM. Moreover, we reveal that ferroptosis-related genes are associated with cytogenetic abnormalities in MM. The ferroptosis-related pathways and genes might impact the osteogenic differentiation of mesenchymal stromal cells in MM patients. A better understanding of the participation of ferroptosis in MM will pave the way for design of new therapies.


Subject(s)
Ferroptosis , Multiple Myeloma , Humans , Multiple Myeloma/genetics , Ferroptosis/genetics , Osteogenesis , Prognosis , Carcinogenesis
7.
Br J Cancer ; 124(11): 1843-1853, 2021 05.
Article in English | MEDLINE | ID: mdl-33785876

ABSTRACT

BACKGROUND: Secondary plasma cell leukaemia (sPCL) is an aggressive form of multiple myeloma (MM), but the mechanism underlying MM progresses into PCL remains unknown. METHODS: Gene expression profiling of MM patients and PCL patients was analysed to identify the molecular differences between the two diseases. Cox survival regression and Kaplan-Meier analysis were performed to illustrate the impact of integrin subunit alpha 6 (ITGA6) on prognosis of MM. Invasion assays were performed to assess whether ITGA6 regulated the progression of MM to PCL. RESULTS: Gene expression profiling analyses showed that cell metastasis pathways were enriched in PCL and ITGA6 was differentially expressed between PCL and MM. ITGA6 expression was an independent prognostic factor for event-free survival (EFS) and overall survival (OS) of MM patients. Moreover, the stratification ability of the International Staging System (ISS) of MM was improved when including ITGA6 expression. Functional studies uncovered that increased ITGA6 reduced the myeloma cell invasion. Additionally, low expression of ITGA6 resulted from epigenetic downregulating of its anti-sense non-coding RNA, ITGA6-AS1. CONCLUSION: Our data reveal that ITGA6 gradually decreases during plasma cell dyscrasias progression and low expression of ITGA6 contributes to myeloma metastasis. Moreover, ITGA6 abundance might help develop MM prognostic stratification.


Subject(s)
Integrin alpha6/genetics , Leukemia, Plasma Cell/genetics , Multiple Myeloma/genetics , Biomarkers, Tumor/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Disease Progression , Down-Regulation/genetics , Down-Regulation/physiology , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Integrin alpha6/physiology , Leukemia, Plasma Cell/diagnosis , Leukemia, Plasma Cell/mortality , Leukemia, Plasma Cell/pathology , Multiple Myeloma/diagnosis , Multiple Myeloma/mortality , Multiple Myeloma/pathology , Prognosis
8.
Bioinformatics ; 36(5): 1649-1651, 2020 03 01.
Article in English | MEDLINE | ID: mdl-31603498

ABSTRACT

SUMMARY: Cancer hallmarks rely on its specific transcriptional programs, which are dysregulated by multiple mechanisms, including genomic aberrations in the DNA regulatory regions. Genome-wide association studies have shown many variants are found within putative enhancer elements. To provide insights into the regulatory role of enhancer-associated non-coding variants in cancer epigenome, and to facilitate the identification of functional non-coding mutations, we present dbInDel, a database where we have comprehensively analyzed enhancer-associated insertion and deletion variants for both human and murine samples using ChIP-Seq data. Moreover, we provide the identification and visualization of upstream TF binding motifs in InDel-containing enhancers. Downstream target genes are also predicted and analyzed in the context of cancer biology. The dbInDel database promotes the investigation of functional contributions of non-coding variants in cancer epigenome. AVAILABILITY AND IMPLEMENTATION: The database, dbInDel, can be accessed from http://enhancer-indel.cam-su.org/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Enhancer Elements, Genetic , Genome-Wide Association Study , Animals , Chromatin Immunoprecipitation Sequencing , Genomics , Humans , Mice , Protein Binding
9.
Stem Cells ; 37(2): 247-256, 2019 02.
Article in English | MEDLINE | ID: mdl-30353595

ABSTRACT

The characteristics of mesenchymal stromal cells (MSCs) which derived from multiple myeloma (MM) patients are typically impaired in osteogenic differentiation. However, the underlying molecular mechanisms need to be further investigated. lncRNAs are emerging as critical regulation molecules in oncogenic pathways. In this study, we identified that bioactive lncRNA HOXC-AS3, which is transcribed in opposite to HOXC10, was presented in MSCs derived from bone marrow (BM) of MM patients (MM-MSCs). HOXC-AS3 was able to interact with HOXC10 at the overlapping parts and this interaction increased HOXC10 stability, then promoted its expression, conferring osteogenesis repression to MM-MSCs. In mouse models, intravenously administered siHOXC-AS3 was proven to be effective in prevention of bone loss, sustained by both anticatabolic activities and bone-forming. These data showed that lncHOXC-AS3 was required for osteogenesis in BM-MSCs by enhancing HOXC10 expression. Our finding thus unveils a novel insight for the potential clinical significance of lncRNA HOXC-AS3 as a therapeutic target for bone disease in MM. Stem Cells 2019;37:247-256.


Subject(s)
Homeodomain Proteins/metabolism , Mesenchymal Stem Cells/metabolism , Multiple Myeloma/metabolism , Oligonucleotides, Antisense/metabolism , Osteoblasts/metabolism , RNA, Long Noncoding/metabolism , Animals , Case-Control Studies , Cell Differentiation/physiology , Cell Line, Tumor , Cells, Cultured , Female , Heterografts , Homeodomain Proteins/genetics , Humans , Mesenchymal Stem Cells/cytology , Mice , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Oligonucleotides, Antisense/genetics , Osteogenesis , RNA, Long Noncoding/genetics , Transfection , Up-Regulation
10.
Bioinformatics ; 34(6): 901-910, 2018 03 15.
Article in English | MEDLINE | ID: mdl-29077795

ABSTRACT

Motivation: Large-scale molecular data have been increasingly used as an important resource for prognostic prediction of diseases and detection of associated genes. However, standard approaches for omics data analysis ignore the group structure among genes encoded in functional relationships or pathway information. Results: We propose new Bayesian hierarchical generalized linear models, called group spike-and-slab lasso GLMs, for predicting disease outcomes and detecting associated genes by incorporating large-scale molecular data and group structures. The proposed model employs a mixture double-exponential prior for coefficients that induces self-adaptive shrinkage amount on different coefficients. The group information is incorporated into the model by setting group-specific parameters. We have developed a fast and stable deterministic algorithm to fit the proposed hierarchal GLMs, which can perform variable selection within groups. We assess the performance of the proposed method on several simulated scenarios, by varying the overlap among groups, group size, number of non-null groups, and the correlation within group. Compared with existing methods, the proposed method provides not only more accurate estimates of the parameters but also better prediction. We further demonstrate the application of the proposed procedure on three cancer datasets by utilizing pathway structures of genes. Our results show that the proposed method generates powerful models for predicting disease outcomes and detecting associated genes. Availability and implementation: The methods have been implemented in a freely available R package BhGLM (http://www.ssg.uab.edu/bhglm/). Contact: nyi@uab.edu. Supplementary information: Supplementary data are available at Bioinformatics online.


Subject(s)
Algorithms , Computational Biology/methods , Genes , Metabolic Networks and Pathways , Models, Biological , Prognosis , Bayes Theorem , Humans , Linear Models , Risk Factors
11.
Bioinformatics ; 34(21): 3609-3615, 2018 11 01.
Article in English | MEDLINE | ID: mdl-29850860

ABSTRACT

Motivation: Molecular analyses suggest that myeloma is composed of distinct sub-types that have different molecular pathologies and various response rates to certain treatments. Drug responses in multiple myeloma (MM) are usually recorded as a multi-level ordinal outcome. One of the goals of drug response studies is to predict which response category any patients belong to with high probability based on their clinical and molecular features. However, as most of genes have small effects, gene-based models may provide limited predictive accuracy. In that case, methods for predicting multi-level ordinal drug responses by incorporating biological pathways are desired but have not been developed yet. Results: We propose a pathway-structured method for predicting multi-level ordinal responses using a two-stage approach. We first develop hierarchical ordinal logistic models and an efficient quasi-Newton algorithm for jointly analyzing numerous correlated variables. Our two-stage approach first obtains the linear predictor (called the pathway score) for each pathway by fitting all predictors within each pathway using the hierarchical ordinal logistic approach, and then combines the pathway scores as new predictors to build a predictive model. We applied the proposed method to two publicly available datasets for predicting multi-level ordinal drug responses in MM using large-scale gene expression data and pathway information. Our results show that our approach not only significantly improved the predictive performance compared with the corresponding gene-based model but also allowed us to identify biologically relevant pathways. Availability and implementation: The proposed approach has been implemented in our R package BhGLM, which is freely available from the public GitHub repository https://github.com/abbyyan3/BhGLM.


Subject(s)
Biological Phenomena , Multiple Myeloma , Algorithms , Bayes Theorem , Humans , Logistic Models , Multiple Myeloma/drug therapy
12.
BMC Cancer ; 18(1): 551, 2018 May 10.
Article in English | MEDLINE | ID: mdl-29747599

ABSTRACT

BACKGROUND: Multiple myeloma (MM), like other cancers, is caused by the accumulation of genetic abnormalities. Heterogeneity exists in the patients' response to treatments, for example, bortezomib. This urges efforts to identify biomarkers from numerous molecular features and build predictive models for identifying patients that can benefit from a certain treatment scheme. However, previous studies treated the multi-level ordinal drug response as a binary response where only responsive and non-responsive groups are considered. METHODS: It is desirable to directly analyze the multi-level drug response, rather than combining the response to two groups. In this study, we present a novel method to identify significantly associated biomarkers and then develop ordinal genomic classifier using the hierarchical ordinal logistic model. The proposed hierarchical ordinal logistic model employs the heavy-tailed Cauchy prior on the coefficients and is fitted by an efficient quasi-Newton algorithm. RESULTS: We apply our hierarchical ordinal regression approach to analyze two publicly available datasets for MM with five-level drug response and numerous gene expression measures. Our results show that our method is able to identify genes associated with the multi-level drug response and to generate powerful predictive models for predicting the multi-level response. CONCLUSIONS: The proposed method allows us to jointly fit numerous correlated predictors and thus build efficient models for predicting the multi-level drug response. The predictive model for the multi-level drug response can be more informative than the previous approaches. Thus, the proposed approach provides a powerful tool for predicting multi-level drug response and has important impact on cancer studies.


Subject(s)
Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/genetics , Gene Expression Profiling , Models, Biological , Multiple Myeloma/drug therapy , Algorithms , Bortezomib/therapeutic use , Clinical Trials as Topic , Datasets as Topic , Humans , Logistic Models , Multiple Myeloma/genetics , Transcriptome/genetics , Treatment Outcome
13.
Mol Pharm ; 15(9): 4139-4147, 2018 09 04.
Article in English | MEDLINE | ID: mdl-30048594

ABSTRACT

Several studies demonstrate that the bromodomain inhibitor OTX015 has an antitumor activity in cancers. However, translation of these data to molecules suitable for clinical development has yet to be accomplished in multiple myeloma (MM). Here, we identified genes and biologic processes that substantiated the antimyeloma activity of OTX015 with global transcriptomics. OTX015 exerted a strong antiproliferative effect and induced cell cycle arrest in vitro. Gene expression profiling uncovered that OTX015 targeted NF-κB, EGFR, cell cycle regulation, and the cancer proliferation signaling pathway. Gene expression signatures displaying various levels of sensitivity to OTX015 were also identified. The data also showed that oral administration of OTX015 displayed significant antitumor activity in the mice model of disseminated human myeloma. In addition, our study provided the first evidence and rationale that OTX015 could promote osteoblast differentiation of mesenchymal stem cells (MSCs) and inhibited osteoclast formation and resorption in vivo experiments. Herein our results expanded the understanding of the mechanism for BET inhibitors OTX015 in MM. Our study provided an impressive basis for the clinical application of the novel antimyeloma agent OTX015 and uncovered signaling pathways that may play key roles in myeloma cell proliferation.


Subject(s)
Acetanilides/therapeutic use , Antineoplastic Agents/therapeutic use , Heterocyclic Compounds, 3-Ring/therapeutic use , Multiple Myeloma/drug therapy , Proteins/antagonists & inhibitors , Animals , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Mice , Multiple Myeloma/metabolism , Osteogenesis/drug effects , Xenograft Model Antitumor Assays
14.
Mol Pharm ; 15(11): 5387-5396, 2018 11 05.
Article in English | MEDLINE | ID: mdl-30339013

ABSTRACT

Treatment failure remains a main challenge in the management of high-risk multiple myeloma (MM) even with the expanding repertoire of new drugs. Combinatorial therapy is considered an encouraging strategy that can overcome the compensatory mechanisms and undesirable off-target effects that limit the benefits of many prospective agents. Preliminary results of a current phase I trial have indicated that the new BET bromodomain inhibitor OTX015 has favorable activity and tolerability. However, OTX015 is not efficacious enough as a monotherapy. Here, we provide evidence that synergistic drug combinations with OTX015 were generally more specific to particular cellular contexts than single agent activities. In addition, pairing OTX015 with three classes of drugs dramatically enhanced the antitumor activity in mouse models of disseminated human myeloma. Our studies further underscored that the BET inhibitor OTX015 sensitized MM cells by interrupting several pathways and genes critical for MM cell proliferation and drug response, which provided the rationale for multiple myeloma therapy with OTX015 combined with conventional chemotherapeutic drugs. Thus, the context specificity of synergistic combinations not only provide profound insights into therapeutically relevant selectivity but also improve control of complex biological systems.


Subject(s)
Acetanilides/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Heterocyclic Compounds, 3-Ring/pharmacokinetics , Multiple Myeloma/drug therapy , Acetanilides/therapeutic use , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cell Line, Tumor , Drug Synergism , Heterocyclic Compounds, 3-Ring/therapeutic use , Humans , Mice , Multiple Myeloma/pathology , Prospective Studies , Proteins/antagonists & inhibitors , Xenograft Model Antitumor Assays
15.
Stem Cells ; 33(6): 1985-97, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25753650

ABSTRACT

Multiple myeloma (MM) is characterized by the impaired osteogenic differentiation of mesenchymal stromal cells (MSCs). However, the underlying molecular mechanisms are still poorly understood. Long noncoding RNAs (lncRNAs) are emerging as important regulatory molecules in tumor-suppressor and oncogenic pathways. Here we showed that MSCs from MM expressed less lncRNA MEG3 relative to those from normal donors during osteogenic differentiation. To evaluate the effect of MEG3 on osteogenesis, bone marrow MSCs with enhanced or reduced MEG3 were prepared. We observed that MEG3 knockdown significantly reduced the expression of key osteogenic markers, including Runt-related transcription factor 2, osterix, and osteocalcin, while overexpression of MEG3 enhanced their expression. Additionally, MEG3 knockdown decreased BMP4 transcription. Here we showed that MEG3 was critical for SOX2 transcriptional repression of the BMP4. MEG3, which is located near the BMP4 gene, could dissociate the transcription factor SOX2 from the BMP4 promoter. A stable complex containing the MEG3, SOX2, and the SOX2 consensus site of BMP4 suggested that MEG3 activated transcriptional activity by directly influencing SOX2 activity. By using assays such as luciferase, chromatin immunoprecipitation, and RNA immunoprecipitation, we showed that MEG3 had a critical function in a mechanism of promoter-specific transcriptional activation. These results suggested that MEG3 played an essential role in osteogenic differentiation in bone marrow MSCs, partly by activating BMP4 transcription. Our data provided novel evidence for the biological and clinical significance of lncRNA MEG3 expression as a potential biomarker for identifying patients with MM and as a potential therapeutic target in MM.


Subject(s)
Bone Morphogenetic Protein 4/genetics , Cell Differentiation/genetics , Mesenchymal Stem Cells/cytology , Multiple Myeloma/metabolism , RNA, Long Noncoding/metabolism , Humans , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Osteogenesis/genetics , RNA, Long Noncoding/genetics , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Transcriptional Activation/genetics , Up-Regulation
16.
J Biol Chem ; 289(42): 29365-75, 2014 Oct 17.
Article in English | MEDLINE | ID: mdl-25187517

ABSTRACT

Long noncoding RNAs (lncRNAs) are emerging as important regulatory molecules in tumor suppressor and oncogenic pathways. However, the magnitude of the contribution of lncRNA expression to normal human tissues and cancers has not been investigated in a comprehensive manner. Here we explored the biology of the lncRNA MALAT1 and considered the potential significance in mesenchymal stem cells from myeloma patients. By using assays such as RNA interference, luciferase, chromatin immunoprecipitation, and RNA immunoprecipitation, we showed that in mesenchymal stem cells MALAT1 promoted the activation effect of the key transcription factor Sp1 on LTBP3 promoter by modulating recruitment of Sp1 to the LTBP3 gene that regulated the bioavailability of TGF-ß in particular. Our data suggested that lncRNA MALAT1 directly interacted with Sp1 and LTBP3 promoter to increase expression of LTBP3 gene. The specificity and efficiency of activation were ensured by the formation of a stable complex between MALAT1 and the LTBP3 promoter, direct interaction of MALAT1 with Sp1, and recruitment of Sp1 to the promoter. In this study, we showed that the mechanism of transcriptional activation of LTBP3 promoter depended on MALAT1 initiated from neighboring gene LTBP3 and involved both the direct interaction of the Sp1 and promoter-specific activation. Our knowledge of the role of MALAT1 in cellular transformation is pointing toward its potential use as a biomarker and a target for novel therapeutic approaches in multiple myeloma.


Subject(s)
Gene Expression Regulation, Neoplastic , Latent TGF-beta Binding Proteins/genetics , Mesenchymal Stem Cells/metabolism , Multiple Myeloma/genetics , RNA, Long Noncoding/genetics , Aged , Aged, 80 and over , Biomarkers, Tumor/metabolism , Female , Gene Expression Profiling , Humans , Latent TGF-beta Binding Proteins/metabolism , Male , Middle Aged , Promoter Regions, Genetic , RNA, Long Noncoding/metabolism , Sp1 Transcription Factor/metabolism
17.
Biochem Pharmacol ; 227: 116466, 2024 09.
Article in English | MEDLINE | ID: mdl-39102989

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma with limited response to chemotherapy. Histone acetylation is reduced in DLBCL. Chidamide, a histone deacetylase inhibitor, shows promise in lymphomas but needs further investigation for DLBCL. Our study indicated that chidamide effectively suppresses DLBCL both in vitro and in vivo. High-throughput RNA sequencing analysis provided comprehensive evidence that chidamide markedly influences crucial signaling pathways in DLBCL, including the MAPK, MYC and p53 pathway. Additionally, we observed substantial variability in the sensitivity of DLBCL cells to chidamide, and identified that elevated expression of BCL6 might confer resistance to chidamide in DLBCL. Moreover, our investigations revealed that BCL6 inhibited chidamide-induced histone acetylation by recruiting histone deacetylase (HDACs), leading to drug resistance in DLBCL cells. Furthermore, we found that lenalidomide targeted BCL6 degradation through the ubiquitination pathway and restore the sensitivity of drug-resistant DLBCL to chidamide. Collectively, these findings provided valuable insights into the global impact of chidamide on DLBCL and highlight the potential of targeting HDACs as a therapeutic strategy for DLBCL. Identifying BCL6 as a biomarker for predicting the response to chidamide and the combination therapy with BCL6 inhibition has the potential to lead to more personalized and effective treatments for DLBCL patients.


Subject(s)
Aminopyridines , Benzamides , Drug Resistance, Neoplasm , Histone Deacetylase Inhibitors , Lymphoma, Large B-Cell, Diffuse , Proto-Oncogene Proteins c-bcl-6 , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/genetics , Histone Deacetylase Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-6/genetics , Proto-Oncogene Proteins c-bcl-6/metabolism , Drug Resistance, Neoplasm/drug effects , Benzamides/pharmacology , Cell Line, Tumor , Animals , Mice , Aminopyridines/pharmacology , Xenograft Model Antitumor Assays/methods , Female , Lenalidomide/pharmacology , Lenalidomide/therapeutic use , Antineoplastic Agents/pharmacology , Mice, SCID
18.
Blood Adv ; 8(18): 4886-4899, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-38875465

ABSTRACT

ABSTRACT: Exosomes have emerged as promising vehicles for delivering therapeutic cargoes to specific cells or tissues, owing to their superior biocompatibility, reduced immunogenicity, and enhanced targeting capabilities compared with conventional drug delivery systems. In this study, we developed a delivery platform using exosomes derived from monocytes, specifically designed for targeted delivery of bortezomib (Btz) to multiple myeloma (MM) cells. Our approach involved the genetic modification of monocytes to express antibodies targeting B-cell maturation antigen (anti-BCMA), because BCMA selectively expresses on myeloma cells. This modified anti-BCMA was then efficiently incorporated into the monocyte-derived exosomes. These adapted exosomes effectively encapsulated Btz, leading to enhanced drug accessibility within MM cells and sustained intracellular accumulation over an extended period. Remarkably, our results demonstrated that anti-BCMA-modified exosome-loaded Btz (anti-BCMA-Exo-Btz) outperformed free Btz in vitro, exhibiting a more potent myeloma-suppressive effect. In orthotopic MM xenograft models, anti-BCMA-Exo-Btz exhibited a significant antitumor effect compared with free Btz. Furthermore, it demonstrated remarkable specificity in targeting Btz to myeloma cells in vivo. Importantly, we observed no significant histological damage in mice treated with anti-BCMA-Exo-Btz and a slight effect on peripheral blood mononuclear cells. In addition, our study highlighted the multifunctional potential of monocyte exosomes, which induced cell apoptosis, mediated immune responses, and enhanced the osteogenic potential of mesenchymal stromal cells. In conclusion, our study suggests that exosomes modified with targeting ligands hold therapeutic promise for delivering Btz to myelomas, offering substantial potential for clinical applications.


Subject(s)
B-Cell Maturation Antigen , Bortezomib , Drug Delivery Systems , Exosomes , Multiple Myeloma , Multiple Myeloma/drug therapy , Multiple Myeloma/therapy , Exosomes/metabolism , Bortezomib/pharmacology , Bortezomib/therapeutic use , Bortezomib/administration & dosage , Humans , Animals , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/administration & dosage , Cell Line, Tumor , Xenograft Model Antitumor Assays , Disease Models, Animal , Monocytes/metabolism
19.
Adv Mater ; 35(12): e2211612, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36626850

ABSTRACT

Light control of emergent quantum phenomena is a widely used external stimulus for quantum materials. Generally, perovskite strontium ruthenate SrRuO3 has an itinerant ferromagnetism with a low-spin state. However, the phase of intermediate-spin (IS) ferromagnetic metallic state has never been seen. Here, by means of UV-light irradiation, a photocarrier-doping-induced Mott-insulator-to-metal phase transition is shown in a few atomic layers of perovskite IS ferromagnetic SrRuO3- δ . This new metastable IS metallic phase can be reversibly regulated due to the convenient photocharge transfer from SrTiO3 substrates to SrRuO3- δ ultrathin films. These dynamical mean-field theory calculations further verify such photoinduced electronic phase transformation, owing to oxygen vacancies and orbital reconstruction. The optical manipulation of charge-transfer finesse is an alternative pathway toward discovering novel metastable phases in strongly correlated systems and facilitates potential light-controlled device applications in optoelectronics and spintronics.

20.
Cancer Sci ; 103(4): 684-90, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22192169

ABSTRACT

Glioblastoma (GBM) is a highly aggressive brain tumor characterized by increased proliferation and resistance to chemotherapy and radiotherapy. Recently, a growing body of evidence suggests that glioma-initiating cells (GICs) are responsible for the initiation and recurrence of GBM. However, the factors determining the differential development of GICs remain poorly defined. In the present study, we show that curcumin, a natural compound with low toxicity in normal cells, significantly induced differentiation of GICs in vivo and in vitro by inducing autophagy. Moreover, curcumin also suppressed tumor formation on intracranial GICs implantation into mice. Our results suggest that autophagy plays an essential role in the regulation of GIC self-renewal, differentiation, and tumorigenic potential, suggesting autophagy could be a promising therapeutic target in a subset of glioblastomas. This is the first evidence that curcumin has differentiating and tumor-suppressing actions on GICs.


Subject(s)
Autophagy , Brain Neoplasms/pathology , Cell Differentiation/drug effects , Curcumin/pharmacology , Glioblastoma/mortality , Glioblastoma/pathology , Neoplastic Stem Cells/drug effects , Animals , Brain Neoplasms/drug therapy , Brain Neoplasms/mortality , Glioblastoma/drug therapy , Humans , Mice , Mice, Nude , Neoplasm Transplantation , Neoplastic Stem Cells/pathology , Tumor Cells, Cultured
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