Project description:Multiple myeloma (MM) progression is characterized by the seeding of cancer cells in different anatomic sites. To characterize this evolutionary process, we interrogated, by whole genome sequencing, 25 samples collected at autopsy from 4 patients with relapsed MM and an additional set of 125 whole exomes collected from 51 patients. Mutational signatures analysis showed how cytotoxic agents introduce hundreds of unique mutations in each surviving cancer cell, detectable by bulk sequencing only in cases of clonal expansion of a single cancer cell bearing the mutational signature. Thus, a unique, single-cell genomic barcode can link chemotherapy exposure to a discrete time window in a patient's life. We leveraged this concept to show that MM systemic seeding is accelerated at relapse and appears to be driven by the survival and subsequent expansion of a single myeloma cell following treatment with high-dose melphalan therapy and autologous stem cell transplant.
Project description:To identify genes responsible for the synergistic effect of DAC with Dex, we performed cDNA microarray analyses using cDNA prepared from Dex-resistant OPM1 cells treated with/without Dex, DAC or DAC+Dex.
Project description:Multiple myeloma (MM) is a neoplastic plasma-cell disorder characterized by clonal proliferation of malignant plasma cells. Despite extensive research, disease heterogeneity within and between treatment-resistant patients is poorly characterized. In the present study, we conduct a prospective, multicenter, single-arm clinical trial (NCT04065789), combined with longitudinal single-cell RNA-sequencing (scRNA-seq) to study the molecular dynamics of MM resistance mechanisms. Newly diagnosed MM patients (41), who either failed to respond or experienced early relapse after a bortezomib-containing induction regimen, were enrolled to evaluate the safety and efficacy of a daratumumab, carfilzomib, lenalidomide and dexamethasone combination. The primary clinical endpoint was safety and tolerability. Secondary endpoints included overall response rate, progression-free survival and overall survival. Treatment was safe and well tolerated; deep and durable responses were achieved. In prespecified exploratory analyses, comparison of 41 primary refractory and early relapsed patients, with 11 healthy subjects and 15 newly diagnosed MM patients, revealed new MM molecular pathways of resistance, including hypoxia tolerance, protein folding and mitochondria respiration, which generalized to larger clinical cohorts (CoMMpass). We found peptidylprolyl isomerase A (PPIA), a central enzyme in the protein-folding response pathway, as a potential new target for resistant MM. CRISPR-Cas9 deletion of PPIA or inhibition of PPIA with a small molecule inhibitor (ciclosporin) significantly sensitizes MM tumor cells to proteasome inhibitors. Together, our study defines a roadmap for integrating scRNA-seq in clinical trials, identifies a signature of highly resistant MM patients and discovers PPIA as a potent therapeutic target for these tumors.
Project description:Multiple myeloma (MM) represents an incurable hematologic malignancy. Despite significant advances over the past decade, with the advent of multiple new classes of anti-myeloma agents, including immunomodulatory drugs, proteasome inhibitors and monoclonal antibodies, patients ultimately relapse. Selinexor is a first-in-class exportin-1 inhibitor with activity in these multiply relapsed and refractory patients. Although the current Food and Drug Administration (FDA) approval is for the doublet of Selinexor in combination with dexamethasone, ongoing clinical trials are evaluating a number of combination regimens. These triplet and quadruplet, selinexor-based, regimens are showing significant activity in "triple-class" refractory patients. With appropriate combination drug choice, drug dosing, and supportive measures, patients with previously no viable options for therapy, now have multiple potential regimens to control their disease.
Project description:The malignant progression of multiple myeloma is characterized by the seeding of cancer cells in different anatomic sites followed by their clonal expansion. It has been demonstrated that this spatial evolution at varying anatomic sites is characterized by genomic heterogeneity. However, it is unclear whether each anatomic site at relapse reflects the expansion of pre-existing but previously undetected disease or secondary seeding from other sites. Furthermore, genomic evolution over time at spatially distinct sites of disease has not been investigated in a systematic manner.
To address this, we interrogated 25 samples, by whole genome sequencing, collected at autopsy from 4 patients with relapsed multiple myeloma and demonstrated that each site had a unique evolutionary trajectory characterized by distinct single and complex structural variants and copy number changes. By analyzing the landscape of mutational signatures at these sites and for an additional set of 125 published whole exomes collected from 51 patients, we demonstrate the profound mutagenic effect of melphalan and platinum in relapsed multiple myeloma. Chemotherapy-related mutagenic processes are known to introduce hundreds of unique mutations in each surviving cancer cell. These mutations can be detectable by bulk sequencing only in cases of clonal expansion of a single cancer cell bearing the mutational signature linked to chemotherapy exposure thus representing a unique single-cell genomic barcode linked to a discrete time window in each patient’s life. We leveraged this concept to show that multiple myeloma systemic seeding is accelerated at clinical relapse and appears to be driven by the survival and subsequent expansion of a single myeloma cell following treatment with high dose melphalan therapy and autologous stem cell transplant.
Project description:The therapeutic strategy for relapsed and refractory multiple myeloma (RRMM) integrates a holistic approach regarding patient, disease, and drug-related factors. Patient-related factors include age, frailty status, and underlying comorbidities, especially cardiovascular and renal diseases and peripheral neuropathies that affect tolerability to multiple drug combinations or transplantations. Disease-related factors encompass these multiple patient-related factors, particularly the aggressiveness of the disease and cytogenetics. Regarding drug-related factors, the approval of novel proteasome inhibitors (such as carfilzomib and ixazomib), immunomodulatory agents (such as pomalidomide), monoclonal antibodies (such as daratumumab and elotuzumab), and new classes of drugs increasingly makes the choice treatment more complex and necessitates a comprehensive summary and an update of the efficacy and toxicities of each antimyeloma drug and its combinations. Further, careful monitoring of the side effects and supportive care throughout the course of treatment are important to achieve better outcomes for patients with RRMM.
Project description:PurposeReolysin, a proprietary isolate of reovirus type III dearing, enters and preferentially induces apoptosis of malignant cells. RAS pathway activation has been associated with more efficient reoviral infectivity and enhanced oncolysis. Reovirus is currently in advanced solid tumor phase I-II trials; no clinical trials have been conducted in patients with hematologic malignancies.Experimental designA phase I trial treated 12 relapsed myeloma patients at two dose levels. Reolysin was infused daily for 5 days every 28 days. Bone marrow specimens were examined by in situ-based hybridization (ISH) for CD138, p38, caspase-3, reoviral RNA, and capsid protein at screening and cycle 1 day 8. Junctional adhesion molecule 1 (JAM-1) and cancer upregulated gene 2 (CUG2) were evaluated in patient samples and multiple myeloma cell lines. Neutralizing anti-reovirus antibody assay was performed weekly during cycle 1.ResultsThere were no dose-limiting toxicities, patients reached the 3 × 10(10) TCID50 daily on days 1 to 5 dose level, and grade 3 laboratory toxicities included neutropenia, thrombocytopenia, and hypophosphatemia. ISH demonstrated reoviral genome confined in multiple myeloma cells. Reoviral capsid protein and caspase-3 were rarely identified within reoviral RNA-positive cells. The longest durations of stable disease were 4, 5, and 8 months.ConclusionsTreatment with single-agent Reolysin was well tolerated and associated with avid reoviral RNA myeloma cell entry but only minimal intracellular reoviral protein production within multiple myeloma cells. Our data support that in multiple myeloma cells, Reolysin-induced oncolysis requires combination therapy, similar to other cancers.