Project description:Multiple myeloma RPMI8226 cells adapted to growth in melphalan display a shift towards Warburg metabolism and modulated oxidative stress signaling. Inhibitors targeting specific enzymes in these pathways are selectively toxic to the melphalan-resistant cells. To investigate large scale alterations in gene expression accompanying melphalan resistance, we used the multiple myeloma cell line RPMI8226 and its melphalan-resistant derivative LR5. The stable isotope labeling by amino acids in cell culture (SILAC) approach.
Project description:Multiple myeloma RPMI8226 cells adapted to growth in melphalan display a shift towards Warburg metabolism and modulated oxidative stress signaling Inhibitors targeting specific enzymes in these pathways are selectively toxic to the melphalan-resistant cells.
Project description:Multiple myeloma RPMI8226 cells adapted to growth in melphalan display a shift towards Warburg metabolism and modulated oxidative stress signaling Inhibitors targeting specific enzymes in these pathways are selectively toxic to the melphalan-resistant cells. The gene expression profiles were measured on 6 batches each of control and melphalan-treated RPMI8226 and RPMI8226-LR5 cells using Illumina Human HT-12 v3 Expression BeadChip (Illumina, San Diego, CA), which enables genome-wide expression analysis (more than 47 000 transcripts) of 24 samples in parallel on a single microarray.
Project description:A predictive gene list for response to high dose melphalan therapy in patients diagnosed with multiple myeloma is generated by combining results from dose response experiments and microarray data using a B-cell line panel and the introduction of multivariate regression techniques. 18 malignant B-cell lines were analyzed by gene expression microarrays and screened for melphalan median dose dependent growth inhibition. Results are used to build a predictive gene list for response to high dose melphalan therapy in multiple myeloma.
Project description:Multiple myeloma is an incurable hematological malignancy that impacts tens of thousands of people every year in the U.S. Treatment for eligible patients includes three stages: induction, consolidation with stem cell rescue, and maintenance. High dose therapy with the DNA alkylating agent, melphalan, remains the primary drug for consolidation therapy in conjunction with autologous stem cell transplant. As a result, melphalan resistance remains a clinical challenge. Here, we use proteometabolomics to examine mechanisms of melphalan resistance in two cell line models. Drug metabolism, steady-state metabolomics, activity-based protein profiling (ABPP), acute treatment metabolomics, and immunoblotting analyses have allowed us to further elucidate metabolic processes contributing to melphalan resistance. Proteometabolomics data indicate that both drug resistant cells have higher levels of pentose phosphate pathway metabolites than their naïve counterparts. Interestingly, we also observed cell line specific changes in purine, pyrimidine and glutathione metabolism that are linked to the differences in steady state metabolism of naïve cells and highlight the heterogeneity of melphalan resistance in these models. Because of the diversity of metabolic changes, our data suggest that omics approaches will be needed to fully examine melphalan resistance in patient specimens and define personalized strategies to optimize the delivery of this therapy.
Project description:To understand whether ILF2 is required to ensure the alternative splicing and processing of specific pre-mRNAs in Multiple Myeloma (MM), both in physiological and DNA damage conditions, we performed RNA sequencing (RNA-Seq) analysis of untreated or melphalan-treated ILF2-depleted JJN3 cells. Non-silencing or ILF2 shRNA transduced JJN3 cells were treated with melphalan for 10 hours.
Project description:Autologous peripheral hematopoietic stem cell transplantation (autoHSCT) is one front-line therapy with high-dose melphalan for multiple myeloma (MM). Patients with MM who receive conditioning regimen with melphalan usually suffer from severe gastrointestinal symptoms, as one of nonhematological toxicities. Aim: It is an urgent demand to develop an effective methods to repair the intestinal injuries in patients with MM receiving conditioning regimen with high-dose melphalan for autoHSCT. Therefore, the protective effects of Human umbilical cord derived-mesenchymal stem cells (hucMSCs) is investigated after infusion into mouse model with melphalan-induce gastrointestinal injuries.
Project description:To understand the mechanistic basis of ILF2’s regulation of mRNA splicing in response to DNA damage in Multiple Myeloma, we performed RNA immunoprecipitation (RIP) and sequencing of ILF2-bound transcripts under both physiological and DNA damage (melphalan treatment) conditions. Cells were treated with melphalan for 10 hours. RNA immunopreciptation (RIP) and sequencing of ILF2-bound RNAs was performed in the JJN3 and H929 cell lines (two biological replicates/condition). Cells were treated with melphalan for 10 hours.
Project description:Background Toxicity of the oral and gastrointestinal mucosa induced by high-dose melphalan is a clinical challenge with no documented prophylactic interventions or predictive tests. The aim of this study was to describe molecular changes in human oral mucosa and to identify biomarkers correlated with the grade of clinical mucositis. Methods and Findings Ten patients with multiple myeloma (MM) were included. For each patient, we acquired three buccal biopsies, one before, one at 2 days, and one at 20 days after high-dose melphalan administration. We also acquired buccal biopsies from 10 healthy individuals that served as controls. We analyzed the biopsies for global gene expression and performed an immunohistochemical analysis to determine HLA-DRB5 expression. We evaluated associations between clinical mucositis and gene expression profiles. Compared to gene expression levels before and 20 days after therapy, at two days after melphalan treatment, we found gene regulation in the p53 and TNF pathways (MDM2, INPPD5, TIGAR), which favored anti-apoptotic defense, and upregulation of immunoregulatory genes (TREM2, LAMP3) in mucosal dendritic cells. This upregulation was independent of clinical mucositis. HLA-DRB1 and HLA-DRB5 (surface receptors on dendritic cells) were expressed at low levels in all patients with MM, in the subgroup of patients with ulcerative mucositis (UM), and in controls; in contrast, the subgroup with low-grade mucositis (NM) displayed 5–6 fold increases in HLA-DRB1 and HLA-DRB5 expression in the first two biopsies, independent of melphalan treatment. Moreover, different splice variants of HLA-DRB1 were expressed in the UM and NM subgroups. Conclusions Our results revealed that, among patients with MM, immunoregulatory genes and genes involved in defense against apoptosis were affected immediately after melphalan administration, independent of the presence of clinical mucositis. Furthermore, our results suggested that the expression levels of HLA-DRB1 and HLA-DRB5 may serve as potential predictive biomarkers for mucositis severity
Project description:To understand the mechanistic basis of YB-1’s regulation of mRNA splicing in response to DNA damage in Multiple Myeloma, we performed RNA immunoprecipitation (RIP) and sequencing of ILF2-bound transcripts under both physiological and DNA damage (melphalan treatment) conditions. Cells were treated with melphalan for 10 hours. (RIP) and sequencing of YB-1-bound RNAs was performed in the JJN3 line (two biological replicates/condition).