Upregulation of CD38 expression on multiple myeloma cells by novel HDAC6 inhibitors is a class effect and augments the efficacy of daratumumab

Multiple myeloma (MM) is incurable, so there is a significant unmet need for effective therapy for patients with relapsed or refractory disease. This situation has not changed despite the recent approval of the anti-CD38 antibody daratumumab, one of the most potent agents in MM treatment. The efficiency of daratumumab might be improved by combining it with synergistic anti-MM agents. We therefore investigated the potential of the histone deacetylase (HDAC) inhibitor ricolinostat to up-regulate CD38 on MM cells, thereby enhancing the performance of CD38-specific therapies. Using quantitative reverse transcription polymerase chain reaction and flow cytometry, we observed that ricolinostat significantly increases CD38 RNA levels and CD38 surface expression on MM cells. Super-resolution microscopy imaging of MM cells by direct stochastic optical reconstruction microscopy confirmed this rise with molecular resolution and revealed homogeneous distribution of CD38 molecules on the cell membrane. Particularly important is that combining ricolinostat with daratumumab induced enhanced lysis of MM cells. We also evaluated next-generation HDAC6 inhibitors (ACY-241, WT- 161) and observed similar increase of CD38 levels suggesting that the upregulation of CD38 expression on MM cells by HDAC6 inhibitors is a class effect. This proof-of-concept illustrates the potential benefit of combining HDAC6 inhibitors and CD38-directed immunotherapy for MM treatme

IKZF1/3 and CRL4-CRBN E3 ubiquitin ligase mutations and IMiD resistance in multiple myeloma

The work was supported by the Deutsche Forschungsgemeinschaft (KFO216), the IZKF, the BTHA and the CDW Stiftung (KMK). UM was supported by a grant of the German Excellence Initiative to the Graduate School of Life Sciences, University of Würzburg.S

Supplementary Appendix. All-trans retinoic acid works synergistically with the γ- secretase inhibitor crenigacestat to augment BCMA on multiple myeloma and the efficacy of BCMA-CAR T cells

Supplement Figure 1: ATRA treatment does not affect the viability of myeloma cell lines. MM.1S, OPM-2 and NCI-H929 cells were treated with ATRA for up to 72 hours. Cell viability was measured by flow cytometry and 7AAD staining (n=6). Bar diagrams show mean values +SD.Supplement Figure 2: ATRA plus crenigacestat treatment enhance BCMA expression on myeloma cell lines. Bar diagram shows BCMA expression on OPM-2 cells (n=3) after treatment with 100 nM ATRA and/or 10 nM GSI crenigacestat for 72 hours. Bar diagram shows mean values +SD. P-values between indicated groups were calculated using unpaired t-test. *p<0.05, **p<0.01.Supplement Figure 3: ATRA treatment leads to increased BCMA transcripts in OPM-2 myeloma cells. BCMA RNA levels in OPM-2 were analyzed by quantitative reverse transcription PCR (qRT-PCR) assay after incubation with increasing doses of ATRA for 48 hours (n=3). Bar diagram shows mean values +SD. P-values between indicated groups were calculated using unpaired t-test. *p<0.05.Supplement Figure 4: ATRA treatment leads to enhanced BCMA expression on primary myeloma cells. Representative flow cytometric analysis of BCMA expression on primary myeloma cells that had been cultured in the absence or presence of ATRA at different concentrations for 72 hours. 7-AAD was used to exclude dead cells from analysis.Supplement Figure 5: ATRA treatment does not impair viability of primary myeloma cells. Viability of primary myeloma cells with or without 72 hours of ATRA treatment was analyzed by flow cytometry and 7-AAD staining (n=5 biological replicates). Bar diagram shows mean values +SD.Supplement Figure 6: sBCMA does not impair BCMA CAR T cell functionality. CD8+ BCMA-CAR T-cells were co-cultured with MM.1S target cells in absence or presence of 150 ng/ml of soluble BCMA. After 4 hours, cytotoxicity was evaluated by bioluminescence- based assay. Diagram shows mean values +/-SD.Supplement Figure 7: ATRA treatment does not increase shedding of sBCMA. sBCMA concentration in the supernatant of OPM-2 and NCI-H929 after incubation with increasing doses of ATRA was analyzed by ELISA. Cell lines were cultured at 1x106/well (n=3 technical replicates). Bar diagrams show mean values +SD, P-values between indicated groups were calculated using 2way ANOVA. n.s. = not significant, *p<0.05, **p<0.01.Supplement Figure 8: BCMA-CAR T-cells confer enhanced cytotoxicity against ATRA plus crenigacestat-treated OPM-2 cells in vitro. OPM-2 cells were incubated with 100 nM ATRA and/or 10 nM GSI for 72 hours or were left untreated. Cytolytic activity of CD8+ BCMA- CAR T-cells was determined in a bioluminescence-based assay after 4h of co-incubation with target cells. Assay was performed in triplicate wells with 5,000 target cells per well. Data are presented as mean values +SD (n=4 biological replicates). P-values between indicated groups were calculated using unpaired t-test. n.s. = not significant, *p<0.05.Supplement Figure 9: Patient-derived BCMA-CAR T-cells confer enhanced cytotoxicity against ATRA-treated MM.1S cells. MM.1S cells were incubated with 50 nM ATRA for 72 hours or were left untreated. Cytolytic activity of MM patient-derived CD8+ BCMA-CAR T-cells was determined in a bioluminescence-based assay after 4h of co-incubation with target cells. Data are presented as mean values +SD of triplicate wells. P-values between indicated groups were calculated using unpaired t-test. *p<0.05, **p<0.01.Peer reviewe

Molecular investigation of the interaction of Neutrophil Extracellular Traps with the human pathogen Neisseria meningitidis

Neisseria meningitidis ist ein wichtiger Erreger von Meningitis und Sepsis insbesondere bei jungen Menschen, gleichzeitig sind hohe Raten asymptomatischen Trägertums bekannt. Als die Virulenz begünstigende Faktoren wurden unter anderem die Kapsel, Pili, äußere Membranvesikel (OMV) und Lipopolysaccharid (LPS) identifiziert, die es dem Erreger erleichtern, das menschliche Immunsystem zu überwinden. Dabei war bisher die Rolle von Neutrophil Extracellular Traps (NETs) als neu beschriebene Komponente der angeborenen Immunantwort nicht untersucht worden. NETs stellen spinnennetzartige DNA-Strukturen mit globulären Proteindomänen dar, die aus neutrophilen Granulozyten entstehen und als antimikrobiell gelten. Ziel dieser Arbeit war es, die Wirkung von NETs auf Meningokokken zu charakterisieren und mögliche Resistenzmechanismen der Bakterien zu identifizieren. In den vorliegenden Versuchen konnte gezeigt werden, dass Meningokokken an NETs binden und durch diese in ihrer Proliferation gehemmt werden. Eine Lokalisation der Bakterien an die NETs konnte dargestellt werden, LPS und Pili wurden als wichtige Strukturen für die Vermittlung der NET-Bindung identifiziert. OMVs zeigten sich als protektiv gegenüber dem Einfluss der NETs, indem sie die Bindung der Erreger an die NETs blockierten. Wenig empfindlich zeigten sich die Bakterien gegenüber Histonen als den quantitativ bedeutsamsten NET-Proteinen. Meningokokken schützen sich gegenüber dem Einfluss der NETs durch Ausbildung von Kapsel und LPS mit intakter Phosphoethanolamin-Modifikation. Ebenso vermitteln zwei Cathelicidin-Resistenzgene den Bakterien einen Überlebensvorteil. Keine Rolle bei der NET-Resistenz spielten die untersuchten Effluxmechanismen. Neuere Untersuchungen von Lappann et al. indentifizierten Meningokokken und OMVs als potente NET-Induktoren. Damit könnten durch die relativ NET-resistenten Mikroorganismen andere Abwehrmechanismen der Neutrophilen konterkariert werden und eine Immunevasion begünstigt werden. Genauere Untersuchungen diesbezüglich stehen noch aus.Neisseria meningitidis is an important pathogenic agent of meningitis and sepsis especially in young adults, at the same time high rates of asymptomatic carriage are well-established. Known factors promoting virulence are, among others, the capsule, pili, outer membrane vesicles (OMV) and the lipopolysaccharide (LPS). In host defense against meningococcal disease, the role of Neutrophil Extracellular Traps (NETs), a recently described component of the innate immune response, had not yet been investigated. NETs are web like structures with globular protein domains that arise from neutrophil granulocytes and are considered being antimicrobial. The aim of the present study was to further investigate interactions between N. meningitidis and NETs and to identify possible resistance mechanisms of meningococci. In this thesis I could demonstrate that meningococci bind to NETs and are therewith being restricted in proliferation. A localization of bacteria to NETs was illustrated, and the mediating effect of LPS and pili on binding was identified. OMVs were shown to be protective against the properties of NETs by blocking the binding of pathogens to NETs. Bacteria were minor sensitive to histones which represent the quantitatively most significant group of proteins in NETs. Meningococci are protected against the effect of NETs by the formation of capsule and LPS when correctly modified with phosphoethanolamine. Two genes involved in cathelicidin resistance were shown to be beneficial on the survival of the bacteria. The investigated efflux mechanisms did not affect resistance to NETs though. Recent data by Lappann et al. identified the role of meningococci and OMVs as potent inducers of NET-formation. This might be a strategy of the NET-resilient microorganism to thwart neutrophil phagocytosis or degranulation and to facilitate immune escape, which is yet to be investigated

Long-Term Disease Control by Pomalidomide-/Dexamethasone-Based Therapy in a Patient with Advanced Multiple Myeloma: A Case Report and Review of the Literature

Background: Therapy for multiple myeloma (MM) has substantially improved in the era of immunomodulatory drugs and bortezomib. However, the prognosis of patients with progressive disease despite treatment with these ‘novel agents' remains poor. Recently, pomalidomide was approved in this setting, but a median progression-free survival of 30 cycles. Conclusion: This case illustrates the value of an individualized approach to myeloma care given an increasing availability of ‘novel agents'. Tailored treatment using these drugs as a backbone is essential to achieve long-lasting responses and minimize side effects

Bispecific Antibodies: A New Era of Treatment for Multiple Myeloma

Despite the introduction of novel agents such as proteasome inhibitors, immunomodulatory drugs, and autologous stem cell transplant, multiple myeloma (MM) largely remains an incurable disease. In recent years, monoclonal antibody-based treatment strategies have been developed to target specific surface antigens on MM cells. Treatment with bispecific antibodies (bsAbs) is an immunotherapeutic strategy that leads to an enhanced interaction between MM cells and immune effector cells, e.g., T-cells and natural killer cells. With the immune synapse built by bsAbs, the elimination of MM cells can be facilitated. To date, bsAbs have demonstrated encouraging results in preclinical studies, and clinical trials evaluating bsAbs in patients with MM are ongoing. Early clinical data show the promising efficacy of bsAbs in relapsed/refractory MM. Together with chimeric antigen receptor-modified (CAR)-T-cells, bsAbs represent a new dimension of precision medicine. In this review, we provide an overview of rationale, current clinical development, resistance mechanisms, and future directions of bsAbs in MM

The influence of baseline characteristics, treatment and depression on health-related quality of life in patients with multiple myeloma: a prospective observational study

Background Multiple myeloma (MM) is the third most common hematologic malignancy with increasing importance due to improving treatment strategies and long-term outcomes in an aging population. This study aims to analyse influencing factors on health-related quality of life (HRQoL), such as treatment strategies, participation in a clinical trial and patient characteristics like anxiety, depression, gender, and age. A better understanding of the individual factors in context with HRQoL could provide a helpful instrument for clinical decisions. Methods In this prospective observational study, the HRQoL of MM patients with different therapies (first-line and relapse) was quantified by standardized questionnaires (EORTC QLQ-C30 and -MY20) in the context of sociodemographic data, individual anxiety and depressiveness (PHQ-4), and a selected number of clinical parameters and symptoms at defined time-points before, during, and after therapy. Results In total, 70 patients were included in the study. The median age of the study cohort was 62 years. 44% were female and 56% were male patients. More than half of the patients were fully active with an ECOG 0. Global health status was significantly higher in patients with first-line treatment and even increased after start of therapy, while the pain level decreased. In contrast, patients with relapsed MM reported a decreasing global health status and increasing pain. Additionally, there was a higher global health status in less anxious/depressive patients. HRQoL decreased significantly after start of chemotherapy in the parameters body image, side effects of treatment, and cognitive functioning. Tandem stem-cell transplantation was not found to be a risk factor for higher impairment of HRQoL. Participation in a clinical study led to an improvement of most aspects of HRQoL. Among others, increased anxiety and depression, female gender, older age, impaired performance status, and recurrent disease can be early indicators for a reduced HRQoL. Conclusion This study showed the importance of regular longitudinal assessments of patient reported outcomes (PROs) in routine clinical care. For the first time, to our knowledge, we were able to demonstrate a potential impact between participation in clinical trials and HRQoL. However, due to frequently restrictive inclusion criteria for clinical trials, these MM patients might not be directly comparable with patients treated within standard therapy concepts. Further studies are needed to clarify the relevance of this preliminary data in order to develop an individualized, patient-centred, therapy concept

Exploration of artificial intelligence use with ARIES in multiple myeloma research

Background: Natural language processing (NLP) is a powerful tool supporting the generation of Real-World Evidence (RWE). There is no NLP system that enables the extensive querying of parameters specific to multiple myeloma (MM) out of unstructured medical reports. We therefore created a MM-specific ontology to accelerate the information extraction (IE) out of unstructured text. Methods: Our MM ontology consists of extensive MM-specific and hierarchically structured attributes and values. We implemented “A Rule-based Information Extraction System” (ARIES) that uses this ontology. We evaluated ARIES on 200 randomly selected medical reports of patients diagnosed with MM. Results: Our system achieved a high F1-Score of 0.92 on the evaluation dataset with a precision of 0.87 and recall of 0.98. Conclusions: Our rule-based IE system enables the comprehensive querying of medical reports. The IE accelerates the extraction of data and enables clinicians to faster generate RWE on hematological issues. RWE helps clinicians to make decisions in an evidence-based manner. Our tool easily accelerates the integration of research evidence into everyday clinical practice

Toxicities of Chimeric Antigen Receptor T Cell Therapy in Multiple Myeloma: An Overview of Experience From Clinical Trials, Pathophysiology, and Management Strategies

In the last few years, monoclonal antibodies (mAbs) such as elotuzumab and daratutumab have brought the treatment of multiple myeloma (MM) into the new era of immunotherapy. More recently, chimeric antigen receptor (CAR) modified T cell, a novel cellular immunotherapy, has been developed for treatment of relapsed/refractory (RR) MM, and early phase clinical trials have shown promising efficacy of CAR T cell therapy. Many patients with end stage RRMM regard CAR T cell therapy as their “last chance” and a “hope of cure”. However, severe adverse events (AEs) and even toxic death related to CAR T cell therapy have been observed. The management of AEs related to CAR T cell therapy represents a new challenge, as the pathophysiology is not fully understood and there is still no well-established standard of management. With regard to CAR T cell associated toxicities in MM, in this review, we will provide an overview of experience from clinical trials, pathophysiology, and management strategies

Current limitations and perspectives of chimeric antigen receptor-T-cells in acute myeloid leukemia

Adoptive transfer of gene-engineered chimeric antigen receptor (CAR)-T-cells has emerged as a powerful immunotherapy for combating hematologic cancers. Several target antigens that are prevalently expressed on AML cells have undergone evaluation in preclinical CAR-T-cell testing. Attributes of an ‘ideal’ target antigen for CAR-T-cell therapy in AML include high-level expression on leukemic blasts and leukemic stem cells (LSCs), and absence on healthy tissues, normal hematopoietic stem and progenitor cells (HSPCs). In contrast to other blood cancer types, where CAR-T therapies are being similarly studied, only a rather small number of AML patients has received CAR-T-cell treatment in clinical trials, resulting in limited clinical experience for this therapeutic approach in AML. For curative AML treatment, abrogation of bulk blasts and LSCs is mandatory with the need for hematopoietic recovery after CAR-T administration. Herein, we provide a critical review of the current pipeline of candidate target antigens and corresponding CAR-T-cell products in AML, assess challenges for clinical translation and implementation in routine clinical practice, as well as perspectives for overcoming them