MDM2 Drives Proteasome Inhibitor Resistance and Represents a TP53-Independent Therapeutic Vulnerability in Multiple Myeloma María Labrador, Sara Cozzubbo, Mariangela Porro, Michela Cumerlato, Cecilia Bandini, et al. Cells, 2026 Proteasome inhibitors (PIs) are central to multiple myeloma (MM) therapy; however, resistance remains a major clinical challenge, particularly in relapsed/refractory disease. To identify functional mediators of carfilzomib (CFZ) resistance, we performed complementary gain-of-function CRISPR activation and pharmacological screening approaches. These unbiased strategies converged on the E3 ubiquitin ligase MDM2 as a modulator of PI response. MDM2 transactivation enhanced MM cell survival and accelerated recovery following CFZ exposure, supporting a causal role in proteotoxic stress tolerance. Pharmacologic inhibition of MDM2 with NVP-CGM097 synergized with CFZ across multiple PI-sensitive and PI-resistant MM cell lines, irrespective of TP53 status. Mechanistically, MDM2 inhibition induced p21 upregulation, cell-cycle arrest, and reduced c-MYC expression, accompanied by impaired activation of DNA damage response mediators. Genetic silencing of MDM2 phenocopied these effects and increased CFZ sensitivity. Importantly, the combination retained efficacy in MM–stromal co-culture models and in primary patient samples, including cases harboring del(17p), while sparing normal peripheral blood mononuclear cells. Collectively, these findings identify MDM2 as a functional driver of PI resistance and support combined MDM2 and proteasome inhibition as a rational therapeutic strategy in MM, including TP53-deficient contexts.
Identification of ceRNA Regulatory Networks Driven by the lncRNA NEAT1 in Multiple Myeloma Domenica Ronchetti, Valentina Traini, Ilaria Silvestris, Giuseppina Fabbiano, Andrea Devecchi, et al. Journal of Cellular and Molecular Medicine, 2026 The lncRNA NEAT1 is overexpressed in multiple myeloma (MM) plasma cells and plays a key role in MM pathogenesis. NEAT1 is involved in ceRNA network in several cancers; however, data in MM are virtually absent. This study identified a NEAT1‐driven ceRNA network involving 96 miRNAs and 40 target genes, selected as concurrently downregulated in NEAT1‐KD AMO1 cells and upregulated in NEAT1‐overexpressing AMO1 cells (AMO1‐OVX). The co‐expression of NEAT1 and the targets was validated in MM patients (GSE116294, GSE13591, GSE6477, CoMMpass), and in NEAT1‐KD NCI‐H929, LP1, and KMS27 cell lines, showing for all targets a consistent downregulation, resembling that of NEAT1. The functional implication of the ceRNA network was explored by functional enrichment analyses of the 40 targets, identifying 78 significant gene sets, 17 of which were found significantly enriched by GSEA analysis in at least one experimental condition among NEAT1‐KD LP1, NCI‐H929, and KMS27 cells, AMO1‐OVX cells, or the extreme quartiles of NEAT1 expression in the CoMMpass dataset. Noteworthy, the cell cycle gene set was validated in 5 out of 6 conditions tested, suggesting that in MM the impact of NEAT1 upregulation on the cell cycle, experimentally demonstrated in our earlier publications, may be attributable, at least partially, to ceRNA mechanisms.
FcγRIIIA Genotype in Plasma Cell Dyscrasias Is Associated with Clinical Progression, Bone Disease Extension and Immune Dysfunction Daniela Cambria, Maria Teresa Cannizzaro, Nunziatina Laura Parrinello, Sara Marino, Ilaria Dulcamare, et al. Cancers, 2026 Background/Objectives: FcγRIIIA presents a single nucleotide polymorphism at position 158 (V/F), which affects its binding affinity to the fragment crystallizable (Fc) of antibodies (Abs). In the presence of immune complexes, FcγRIIIA can mediate the inflammatory signaling, severity of bone disease, and osteoclastogenic activity. Based on this functional relevance, we hypothesized that the FcγRIIIA F158V polymorphism may influence the clinical presentation of multiple myeloma (MM). Methods: FcγRIIIA F158V genotyping was performed on genomic DNA extracted from peripheral blood samples of patients affected by MM or asymptomatic conditions named MGUS and SMM. We compared the allele frequency of FcγRIIIA-F158V polymorphism in 72 MM, 42 MGUS and 31 SMM and evaluated the association with clinical features and occurrence of high-risk chromosome abnormalities. Targeted NGS mutation analysis was performed on genomic DNA isolated from purified CD138+ bone marrow plasma cells (BMPCs) of 41 patients, to evaluate the association between somatic mutations and the FcγRIIIA F158V genotype. Results: the FcγRIIIA-158 V/V homozygous genotype was associated with high-risk cytogenetics, anemia, high beta-2 microglobulin levels, and more than 10 osteolytic lesions. V/V homozygous genotype was significantly associated with at least one mutation in RAS pathway genes (N-RAS, K-RAS or B-RAF). In the immune microenvironment, patients carrying the V/V homozygous genotype had a higher percentage of CD14+CD16++ non-conventional inflammatory monocytes than the V/F or FF genotype. Conclusions: Our study contributes to a better understanding of the interactions between genetic variants, tumor microenvironment, and therapeutic response in plasma cell dyscrasias, to identify molecular biomarkers for precision medicine in MM, MGUS and SMM.
Immunogenetic Architecture of Chronic Lymphocytic Leukemia at Early Stage: Insights from the O-CLL1 Cohort Davide Bagnara, Andrea Nicola Mazzarello, Monica Colombo, Ennio Nano, Niccolò Cardente, et al. Antibodies, 2026 Background/Objectives: The immunoglobulin heavy-chain variable (IGHV) gene repertoire represents a characteristic feature of chronic lymphocytic leukemia (CLL), although its configuration is not well defined at the early disease stages. The IGHV repertoire of a cohort of early CLL patients was analyzed and compared to that of a “real-world” reference cohort. Methods: Patients from the O-CLL1 observational protocol, which enrolled only Binet stage A cases within twelve months from diagnosis, were studied. IGHV/IGHJ rearrangements were sequenced and annotated following ERIC recommendations, and stereotyped subsets were assigned using ARResT/AssignSubsets. The repertoire features were compared with the dataset of a real-world cohort of patients with heterogeneous staging (CTR cohort) and with published early-diagnosis series. Results: IGHV and IGHJ gene distributions and HCDR3-length profiles in O-CLL1 closely mirrored those of CTR, indicating that the BcR IG repertoire at diagnosis is already defined rather than being selected during disease progression. Mutated IGHV (M-CLL) predominated, with a frequency of stereotyped BcR IG comparable to that of other early-diagnosis cohorts. However, within this conserved framework, subset #4 was over-represented among M-CLL from O-CLL without an increased overall IGHV4-34 gene usage, suggestive of a selective expansion rather than a recombinational bias. Subset #4 cases retained canonical HCDR3 motifs and showed time-to-first-treatment like other M-CLL, likely reflecting the younger age structure of O-CLL1. Conclusions: Early-diagnosis CLL displays a biased IGHV repertoire with stereotyped configurations characteristic of CLL, including subsets that are rare in the normal B-cell repertoire. These findings support a central role for antigen-driven selection in shaping CLL evolution.
EXPLORING THE TRANSCRIPTIONAL PROFILE OF DIS3 CAN UNRAVEL NEW TARGETING STRATEGIES IN MULTIPLE MYELOMA Christian Boni Haematologica, 2026 Introduction. Multiple myeloma (MM) is a rare hematologic malignancy marked by neoplastic transformation of plasma cells (PCs) that are characterized by deep genomic instability. Karyotype abnormalities are considered early events in MM, whereas gene mutations arise later and are related to disease progression. Mutations of DIS3 were found in 10% of MM patients and were preferentially localized within the major ribonuclease (RNB) domain affecting its catalytic activity. In addition, del(13q) found in 40% of MM cases, impact the expression of DIS3. This gene encodes a highly conserved 3′–5′ exoribonuclease associated with the RNA-exosome complex essential for RNA turnover. Here, we characterized the transcriptional landscape induced by DIS3 silencing in an MM cell line and exploited the resultant signature to identify putative synergistic compounds.Methods. DIS3 silencing was performed using LNA-gapmeR designed for gymnosis. Transcriptome profiling by bulk RNA-seq of DIS3-silenced NCI-H929 cells versus gapmeR scrambled as controls was carried out on an Illumina NextSeq 500; DESeq2 pipeline was used for differentially expressed genes analysis. Immunofluorescence experiments were performed using anti α-Tubulin 488-conjugated for mitosis and S9.6 antibody for R-loop detection.Results. Differential expression analysis of RNA-seq identified 809 significantly deregulated genes (FDR<0.05), particularly 492 and 317 genes were found upregulated and downregulated respectively. GO bioprocess analysis of downregulated genes were enriched in microtubule and kinetochore assembly, promoting regulatory role of DIS3 in mitotic spindle organization. Interestingly, upregulated genes were predominantly associated with antiviral immune response and interferon-mediated signaling, a pattern possibly due to RNA accumulation. Additionally, immunofluorescence staining of DIS3 silenced cells showed increased R-Loop formation. To identify synergistic agents consistent with DIS3KD signature, the CMap query analysis revealed a strong association with microtubule-targeting inhibitors. Filanesib (ARRY-520) is a selective kinesin inhibitor of EG5/KIF11 that is fundamental mitotic kinesin necessary for spindle orientation. It has been previously studied for MM therapy—either as monotherapy or in combination—within phase II clinical trials. Filanesib treatment negatively affected cell viability in MM cell lines harboring del(13q) compared to bi-allelic WT counterparts. Furthermore, co-treatment with Filanesib and DIS3 LNA-gapmer produced a synergistic cytostatic response.Conclusions. Our rusults suggest that DIS3KD perturbs mitotic spindle dynamics and fosters genomic instability in MM, consistent with prior evidence that DIS3 depletion increases G0/G1-phase accumulation and compromises centrosome formation. In addition, the synergy observed with a microtubule-targeting agent could encourage future investigation to improve MM treatment strategies.
NONO SHAPES MULTIPLE MYELOMA PROGRESSION THROUGH PARASPECKLE-DEPENDENT AND INDEPENDENT PATHWAYS Elisa Taiana Haematologica, 2026 Introduction: Multiple myeloma (MM) is an incurable cancer caused by malignant proliferation of bone marrow plasma cells. The lncRNA NEAT1, the scaffold of paraspeckle (PS), promotes MM progression by regulating DNA repair and cell survival. NONO, which stabilizes NEAT1 and supports PSs biogenesis, is upregulated in MM and associated with poor survival. In addition to its essential role within PSs, NONO may also have functions beyond PSs. This study aims to define how NONO shapes the transcriptomic landscape of MM plasma cells, both through its PS-associated and independent mechanisms.Methods. RNA was extracted from NONO-KD, NEAT1-KD, and scramble AMO1 and LP1 human MM cells lines (HMCL). RNA-seq libraries were prepared following Illumina Stranded TotalRNA PrepLigation with Ribo-zero Plus protocol (Illumina). Sequencing was performed on Illumina Novaseq 6000 S2 cartridge. CoMMpass data were retrieved from the Interim Analysis 15a (MMRF_CoMMpass_IA15a).Results. To investigate the role of NONO in both PS-related and independent pathways, we compared transcriptomic data from NONO-KD and NEAT1-KD AMO1 and LP1 cells. Overlapping pathways suggested PS-related functions. Silencing NEAT1 or NONO led to significant downregulation of gene sets involved in chromatin modification, as well as WNT/β-catenin and NOTCH signalling pathways. Consistently, RNAseq analysis of NEAT1-overexpressing AMO1 cells revealed positive modulation of the same pathways. Further validation came from GSEA of CoMMpass samples stratified by NONO expression, comparing the two extreme quartiles.Since NONO is essential for protecting NEAT1 from degradation, its silencing results in a marked downregulation of NEAT1 expression levels, thus impacting the transcriptome of NONO-KD cells in a NEAT1-dependent manner. As a result, all the pathways modulated in the NONO-KD HMCLs were also confirmed in the NEAT1-KD samples, making it impossible to identify any pathways regulated by NONO independently of PSs. However, the analysis of data from the extreme quartile of NONO in the CoMMpass dataset identified pathways absent in NEAT1-KD HMCLs, suggesting PS-independent roles for NONO in RNA processing, RNA trafficking, mitochondrial biogenesis, and cell-cell communication. To validate pathways selectively regulated by NONO independently of PS, we focused on its role in intercellular communication and adhesion. Functionally, HUVECs cultured in conditioned media from NONO-KD AMO-1 or NCI-H929 cells showed disrupted VE-cadherin localization and expression, indicating that the NONO-dependent MM secretome can alter endothelial adhesion. These results reveal a potential PS-independent role for NONO in modulating the tumor microenvironment.Conclusions. This study highlights the multifaceted transcriptional roles of NONO in MM, revealing both PS-dependent and -independent functions, and underscores its potential impact on tumor microenvironment regulation and disease progression.
DISSECTION OF NEAT1’S ROLE IN TRANSCRIPTIONAL REGULATION REVEALS ACTIONABLE TARGETS IN HIGH-RISK MULTIPLE MYELOMA Noemi Puccio Haematologica, 2026 Introduction. LncRNAs emerged as a key element of genome regulation, driving multiple myeloma (MM) progression and therapy resistance. Among them, NEAT1 has been described as overexpressed in MM patients, promoting malignant PC proliferation. Besides its conventional function in the assembly of paraspeckles, we recently demonstrated that NEAT1 is directly involved in transcriptional control. In this study, we deepen our understanding of NEAT1’s mechanistic function in shaping the activity of transcriptional bodies, providing the rationale for targeted therapeutic intervention.Methods. We used an RNA-seq approach in NEAT1 KD and in CRISPRa NEAT1 overexpressing AMO-1 cell line to derive a NEAT1 transcriptomic signature. Unsupervised clustering analysis in the CoMMpass dataset was used to validate the clinical relevance of the NEAT1 gene program. Computational approaches were used to predict a list of transcriptional regulators of NEAT1’s signature. RNA immunoprecipitation (RIP) and RNA-FISH combined with immunofluorescence (IF) were used to confirm the in silico prediction in AMO-1 and NCI-H929 cell lines. Chromatin immunoprecipitation (ChIP) was employed to validate the involvement of NEAT1 in the transcriptional apparatus. High-throughput (HT) drug screening in NEAT1 KD cells was used to identify small compounds that interfere with NEAT1-dependent transcriptional activity. Rescue experiments were performed using NEAT1 overexpressing cells.Results. Transcriptomic analysis in NEAT1 KD and in NEAT1 overexpressing AMO-1 cell line revealed 378 NEAT1 targets. Unsupervised clustering analysis based on their expression segregated CoMMpass patients into two distinct groups, displaying high or low NEAT1 transcriptional activity. The cluster with the high NEAT1 transcriptional program showed reduced survival and was enriched in high-risk cytogenetic lesions, including 1q gain/amp and del(17)p. Noticeably, computational analysis predicted FOXM1 and CDK9 as upstream regulators of the NEAT1 program, both components MMB:FOXM1 transcriptional apparatus, which controls the expression of G2/M genes. Consistently, we highlighted that 60% of NEAT1 target genes harbor a Cell cycle homology region (CHR) motif, recognized by MMB:FOXM1 complex. In vitro molecular validation confirmed co-localization of NEAT1 and FOXM1 condensates in MM cells, and direct binding of NEAT1-FOXM1/NEAT1-CDK9. Additionally, we demonstrated that NEAT1 KD results in a reduced occupancy of FOXM1 at the promoters of CHR genes. HT drug screening revealed a synthetic lethal interaction between NEAT1 depletion and CDK9 inhibition, whereas its overexpression confers resistance to CDK9 blockade, confirming the interplay between NEAT1-CDK9 to sustain the mitotic gene program.Conclusions. These findings demonstrate that NEAT1 coordinates the expression of mitotic genes through the interaction with FOXM1 and CDK9, providing a mechanistic rationale for targeted interventions in high-risk patients.
The accuracy of administrative data in identifying pulmonary metastases: a population-based study in Northern Italy Francesco Marinelli, Maria Barbara Braghiroli, Isabella Bisceglia, Francesca Roncaglia, Annamaria Pezzarossi, et al. European Journal of Cancer Prevention, 2026 Objective Lung cancer remains a highly prevalent and lethal disease, with the majority of tumors identified at advanced stages. Screening with low-dose CT was shown to be effective in reducing mortality through early diagnosis. Administrative data are increasingly utilized in clinical settings and research for identifying metastatic lung cancer, yet their accuracy and limitations require thorough evaluation. Methods This study evaluated the use of administrative data to identify lung cancer metastases within the population-based cancer registry (CR) of Reggio Emilia by cross-referencing registry data with administrative hospital discharge records (HDRs). Distant metastases were identified using specific International Classification of Diseases, 9th revision codes, with medical records reviewed to validate and refine the identification process. Standardized incidence and mortality rates were calculated and analyzed using joinpoint regression. Results Between 2018 and 2021, 1391 lung cancers exhibiting at least one HDR were identified. Of these, 383 (27.5%) cases had distant metastases, 80 (6%) had a second tumor, and 12 (1.5%) had unknown tumor sites. After a manual review of cases with codes 196 (secondary and unspecified malignant neoplasm of lymph nodes) and code 199 (malignant neoplasm without specification of the site), the number of identified metastatic tumors increased to 30.5%. Lung cancer metastases identified by the CR showed an HDR sensitivity equal to 32.6%. Conclusion Administrative data, even with manual verification, achieved a positive predictive value of 30.5 for metastatic tumors. The scientific community and policymakers must be aware of these limitations and the need for additional resources to accurately screen to evaluate lung cancer.
