Udo Oppermann

Multiple myeloma is a genetically complex plasma cell malignancy in which profound intra-tumoral heterogeneity shapes disease progression and therapeutic resistance. Genomic subclones dynamically emerge and evolve under treatment pressure, yet their spatial organization within intact bone marrow remains poorly defined. We hypothesized that genetically distinct myeloma subclones occupy spatially discrete ecological niches associated with unique molecular and microenvironmental states. To test this, we here demonstrate a proof-of-concept spatial tri-omics workflow combining laser capture microdissection-based genomics and deep LC-MS/MS proteomics with single-cell spatial transcriptomics, integrated by digital co-registration of adjacent tissue sections. Applied to a myeloma bone marrow trephine, this approach enabled coordinated profiling of matched anatomical regions demonstrating that genomic, transcriptomic and proteomic profiles converged to define clone-specific microenvironmental programmes. We show that genetically distinct myeloma subclones occupy mutually exclusive regions of the same bone marrow biopsy. Remarkably, an aggressive del(17p) clone and a gain(12q) clone occupied defined anatomical territories within the same trephine-biopsied section, each clone exhibiting distinct genomic, transcriptomic, proteomic and cellular ecosystems. The del(17p) clone localized to a fibrotic, osteolytic and angiogenic niche enriched for activated stromal cells, osteoblasts, osteoclasts and immunoregulatory myeloid populations, whereas the gain(12q) clone occupied a comparatively quiescent marrow niche with limited stromal remodelling. Together, these findings demonstrate that genetically distinct myeloma subclones establish spatially and biologically discrete ecological niches through coordinated remodelling of stromal, immune and bone compartments, providing a framework for understanding clonal evolution within the bone marrow microenvironment.

Chondrocyte hypertrophy is a key hallmark of osteoarthritis (OA) that drives a multitude of whole-joint disease processes. There are no approved disease-modifying pharmaceuticals in clinical use, emphasising the urgent need for innovative therapeutics. Screening of a focussed chemical library using a novel in vitro platform discovered that inhibition of CDK8/19 mediator kinases modulated chondrocyte behaviours with potential to limit OA hallmarks. Transcriptomic analysis of various chondrogenic cell populations revealed that CDK8/19-inhibitor treatment upregulated pro-anabolic/anti-catabolic markers, downregulated markers of hypertrophy and protected from IL1β-induced extracellular matrix degradation. CDK8 was also found to be upregulated in chondrocytes in vitro following IL1β stimulation. This translated to human OA cartilage, where CDK8, MED12 and pSTAT1 were found to co-localise to cartilage lesions. Exposure to CDK8/19-inhibitor modified cell metabolism in hypertrophic chondrocytes and reduced inflammatory processes in THP-1-derived macrophages. CDK8/19-inhibitor treatment of the STR/Ort mouse corrected gait asymmetry and improved treadmill completion rates, whilst suppressing weight gain and serum OA biomarkers. Histological analyses of STR/Ort mouse knee joints revealed that in vivo CDK8/19-inhibitor treatment upregulated chondromodulin-1, matrillin-3 and enhanced proteoglycan deposition in the pericellular matrix of growth plate/articular cartilage. Micro computed tomography (µCT) showed that CDK8/19-inhibitor treatment modified chondrocyte endochondral behaviours to limit the number and density of mineralised growth plate bridges, which otherwise accumulate with age in STR/Ort mice. Collectively, these data highlight CDK8/19 inhibition as a promising disease-modifying strategy for targeting whole-joint disease in OA and, for the first time, show that CDK8/19 inhibition exerts pivotal control of multiple cellular processes that are crucial to endochondral ossification/OA.

Stromal cell states are altered in active Crohn’s disease (CD), but their origin and phenotypic stability are unknown. Using single-cell spatial transcriptomics, RNA sequencing and ATAC sequencing of ~2,500,000 cells, we map 18 distinct stromal cell states within their cellular and cytokine signaling environments in human full-thickness CD bowel. Inflammatory fibroblasts (IFs) reside in immune cell-rich mucosal ulcers and are induced through combinatorial cytokine exposure suppressing submucosal universal fibroblast programs. The IF state is stabilized through transcription factor (TF) activity of GLI3, TWIST1, ETV4, PRDM1 and RELB, and does not spontaneously revert; however, histone deacetylase inhibition destabilizes the IF state, preventing IF secretome-induced epithelial transmigration and activation of neutrophils. The IF open chromatin configuration is distinct from that of fibrotic contractile stroma, which populate adjoining immune-depleted submucosal fibrotic niches. These findings show that microenvironments in pathological tissue niches shape open chromatin configuration of stromal states that are amenable to modulation by epigenetic modifiers.

Radiotherapy (RT) is a cornerstone of glioblastoma (GBM) treatment, yet therapeutic resistance remains nearly universal due to the rapid activation of stress-adaptive survival programs. Identifying molecular regulators that sustain these adaptive responses may reveal context-dependent vulnerabilities that can be therapeutically exploited. Here, we performed an epigenetic drug screen under low-dose irradiation to identify modifiers of radiotherapy response in glioblastoma. We identify BRD9 inhibition as a priming strategy that selectively enhances irradiation-induced lethality without inducing substantial cytotoxicity under baseline conditions. Mechanistically, BRD9 perturbation delays the resolution of irradiation-induced DNA damage, leading to increased apoptosis following irradiation. This effect is selective for malignant glioblastoma cell lines and patient-derived primary cells, while sparing non-malignant human astrocytes. Transcriptomic profiling reveals that BRD9 inhibition or genetic depletion produces a coordinated, MYC-centered suppression of translational programs, including ribosome biogenesis, rRNA processing, tRNA aminoacylation, and translational initiation. Ectopic MYC expression attenuates BRD9-dependent radiosensitization, functionally linking MYC suppression to the enhanced radiation response. Importantly, analysis of independent glioblastoma patient cohorts reveals a consistent positive association between BRD9 and MYC expression, alongside elevated BRD9 expression in recurrent compared with primary tumors. Together, these findings identify BRD9 as a regulator of MYC-associated translational programs and support its therapeutic targeting as a strategy to enhance radiotherapy efficacy in glioblastoma.

Systemic amyloidosis is typically diagnosed only after irreversible organ damage has occurred, limiting the effectiveness of available therapies. Whether the disease is preceded by detectable molecular changes long before clinical presentation has remained unclear. Here, we leveraged population-scale plasma proteomics and longitudinal follow-up from the UK Biobank to investigate early circulating protein signatures associated with future diagnosis of amyloidosis. Among approximately 53,000 participants with proteomic profiling, we identified 61 individuals who developed amyloidosis up to 14 years after protein assessment. Differential expression and correlation analyses identified a seven-protein panel, including MYL3, MYBPC1, NT-proBNP, NPPB, FCRLB, IGFBP1, and FABP1, consistent with early cardiac stress and immune dysregulation. Time-to-event modelling demonstrated robust stratification of amyloidosis risk and timing. Importantly, a parsimonious subset of these proteins retained strong predictive performance, indicating that a reduced set of biologically informative markers is sufficient for risk stratification. Furthermore, these proteomic signals were not explained by pre-existing cardiac disease, clonal haematopoiesis, or related plasma cell disorders, indicating that they capture disease-specific biological processes preceding clinical diagnosis. Together, these findings show that amyloidosis is preceded by persistent plasma proteomic alterations, providing a framework for early risk stratification and insight into the preclinical biology of this under-recognised disease.

Glioblastoma (GBM) is an aggressive primary brain tumor associated with a median survival of approximately 15 months following diagnosis. Current standard-of-care treatment includes surgical resection followed by radiotherapy and chemotherapy with the DNA-alkylating agent temozolomide (TMZ). However, tumor recurrence in a therapy-resistant state remains a major driver of poor patient outcomes. To investigate the molecular mechanisms underlying TMZ resistance, we generated in vitro models of acquired resistance by exposing initially TMZ-sensitive GBM cells to escalating doses of TMZ. Transcriptomic and chromatin accessibility profiling revealed extensive remodeling of DNA damage response (DDR) and DNA repair pathways that favored protection against TMZ-induced genotoxic stress. Although upregulation of O-6-methylguanine-DNA methyltransferase (MGMT) emerged as a dominant determinant of resistance in our models, the data suggested that additional adaptive resistance mechanisms contribute to the resistant phenotype. To identify targetable epigenetic dependencies associated with TMZ resistance, we performed a chemical screen using an epigenetic probe library. This screen identified multiple histone deacetylase (HDAC) inhibitors that selectively impaired the viability of TMZ-resistant cells, either as monotherapy or in combination with TMZ. Among these, HDAC6-selective inhibitors, including Ricolinostat, were particularly effective at inducing cell death in TMZ-resistant GBM models. Mechanistically, HDAC6 inhibition reduced the expression of key DDR-associated genes, while MGMT responses varied depending on cellular context and treatment duration. Furthermore, pharmacological inhibition and loss-of-function studies demonstrated that targeting HDAC6 could restore TMZ sensitivity by altering the balance of DNA repair pathway activity, potentially acting as a compensatory mechanism for MGMT-mediated resistance. Collectively, our findings identify HDAC6 as an epigenetic vulnerability in acquired TMZ-resistant GBM and support the therapeutic potential of HDAC6 inhibition as a strategy to overcome TMZ resistance in glioblastoma patients.

Belantamab mafodotin, an antibody-drug conjugate targeting B-cell maturation antigen, has demonstrated significant clinical efficacy in combination therapies for relapsed or refractory multiple myeloma. Belantamab mafodotin exerts therapeutic effects through the cytotoxic action of its payload, monomethyl auristatin F, along with its ability to mediate antibody-induced cell death. Significant long-term clinical responses were previously observed in monotherapy treatment – even in patients undergoing dose holds – suggesting involvement of the adaptive immune system. Here, we show that belantamab mafodotin induces markers of immunogenic and inflammatory cell death in vitro and ex vivo. Belantamab mafodotin monotherapy treatment results in an acute inflammatory response that is detectable in patient serum within 24 hours, with increases in granzyme B, CXCL9, CCL3, and CCL4 linked to response depth. High expression of receptors LRP1 and TLR2 that mediate immunogenic cell death on patients’ monocytoid (monocyte/macrophage) cells suggests an important function of the monocytoid lineage to mediate the observed inflammation and immunogenic cell death cascades. Inflammation is followed by remodeling of the innate and adaptive immune system, with a reduction in immune inhibitory signaling alongside the emergence of a CD4 granzyme B-expressing cell population in patients who are in remission vs those that relapse. The ability of belantamab mafodotin to promote adaptive immune responses in addition to its cytotoxic activity may help explain the durable responses observed in treated patients with relapsed/refractory multiple myeloma, despite dose and schedule modifications. Key points Belantamab mafodotin induces immunogenic and inflammatory cell death to remodel the tumor microenvironment in patients Development of adaptive immunity may explain lasting effects seen in belantamab mafodotin-treated patients with RRMM

Background: Uterine fibroids (UFs), benign tumours prevalent in up to 80% of women of reproductive age, are associated with significant morbidity, including abnormal uterine bleeding, pain and infertility. Despite identification of key genomic alterations in MED12 and HMGA2, the pathogenic mechanisms underlying UFs and heavy menstrual bleeding (HMB) remain poorly understood. Methods: To correlate systematically genetic, transcriptional and proteomic phenotypes, we conducted an integrative multi-omic approach utilising targeted DNA sequencing, RNA sequencing and proteomic methodologies, encompassing fibroid, myometrium, and endometrium tissues from 91 patients. Results: In addition to confirming the presence of MED12 mutations, we identify variants in AHR and COL4A6. Multi-omic analysis of endometrium identifies latent factors that correlate with HMB and fibroid presence with driver mutations of MED12, AHR, and COL4A6, which are associated with pathways involved in angiogenesis, extracellular matrix organisation and RNA splicing. We propose a model, supported by in vivo evidence, where altered signalling of MED12-mutated fibroids influences RNA transcript isoform expression in endometrium, potentially leading to abnormal uterine bleeding. Conclusions: This study presents a comprehensive integrative approach, revealing that genetic alterations in UF may influence endometrial function via signalling impacts on the RNA splicing mechanism. Our findings advance the understanding of complex molecular pathways in UF pathogenesis and UF-associated endometrial dysfunction, offering insights for targeted therapeutic development.

Thioneins are cysteine-rich apoproteins that regulate divalent metal homeostasis by virtue of their metal-chelation properties resulting in the ligand-bound metallothionein state. Previous studies show transient upregulation of the metallothionein (MT) gene cluster as part of a complex transcriptional response to a class of histone demethylase tool compounds targeting human Fe ²⁺ dependent ketoglutarate oxygenases KDM6A (UTX) and KDM6B (JmjD3). The prototypic bioactive KDM6 inhibitor GSK-J4 induces apoptotic cell death in multiple myeloma cells and corresponding transcriptomic profiles are dominated by metal and metabolic stress response signatures, also observed in primary human myeloma cells. Here we investigate the hypothesis that metal-chelation by GSK-J4 provides the means for transport and intracellular release of Zn ²⁺ leading to a metallothionein transcriptomic response signature. Live cell imaging of myeloma cells shows transient increases in intracellular free Zn ²⁺ concentrations when exposed to GSK-J4, consistent with a model of inhibitor-mediated metal transport. Comparisons of GSK-J4 and ZnSO ₄ treatments in the presence or absence of metal chelators show that both treatment conditions induce different transcription factor repertoires with an overlapping MTF1 transcriptional regulation responsible for metallothionein and metal ion transport regulation. The data provide a possible explanation for the observed metal response upon GSK-J4 inhibition however the relationship with the pro-apoptotic mechanism in myeloma cells requires further investigation.

Macrophages contribute to the induction and resolution of inflammation and play a central role in chronic low-grade inflammation in cardiovascular diseases caused by atherosclerosis. Human milk oligosaccharides (HMOs) are complex unconjugated glycans unique to human milk that benefit infant health and act as innate immune modulators. Here, we identify the HMO 3′sialyllactose (3′SL) as a natural inhibitor of TLR4-induced low-grade inflammation in macrophages and endothelium. Transcriptome analysis in macrophages revealed that 3′SL attenuates mRNA levels of a selected set of inflammatory genes and promotes the activity of liver X receptor (LXR) and sterol regulatory element binding protein-1 (SREBP1). These acute antiinflammatory effects of 3′SL were associated with reduced histone H3K27 acetylation at a subset of LPS-inducible enhancers distinguished by preferential enrichment for CCCTC-binding factor (CTCF), IFN regulatory factor 2 (IRF2), B cell lymphoma 6 (BCL6), and other transcription factor recognition motifs. In a murine atherosclerosis model, both s.c. and oral administration of 3′SL significantly reduced atherosclerosis development and the associated inflammation. This study provides evidence that 3′SL attenuates inflammation by a transcriptional mechanism to reduce atherosclerosis development in the context of cardiovascular disease.