Circulating RNA biomarkers in diffuse large B-cell lymphoma : a systematic review

Diffuse large B-cell lymphoma (DLBCL) is the most common histological subtype of non-Hodgkin's lymphomas (NHL). DLBCL is an aggressive malignancy that displays a great heterogeneity in terms of morphology, genetics and biological behavior. While a sustained complete remission is obtained in the majority of patients with standard immunochemotherapy, patients with refractory of relapsed disease after first-line treatment have a poor prognosis. This patient group represents an important unmet need in lymphoma treatment. In recent years, improved understanding of the underlying molecular pathogenesis had led to new classification and prognostication tools, including the development of cell-free biomarkers in liquid biopsies. Although the majority of studies have focused on the use of cell-free fragments of DNA (cfDNA), there has been an increased interest in circulating-free coding and non-coding RNA, including messenger RNA (mRNA), microRNA (miRNA), long non-coding RNA (lncRNA) and circular RNA (circRNA), as well as RNA encapsulated in extracellular vesicles or tumor-educated platelets (TEPs). We performed a systematic search in PubMed to identify articles that evaluated circulating RNA as diagnostic, subtype, treatment response or prognostic biomarkers in a human DLBCL population. A total of 35 articles met the inclusion criteria. The aim of this systematic review is to present the current understanding of circulating RNA molecules as biomarker in DLBCL and to discuss their future potential

Selective glucocorticoid receptor-activating adjuvant therapy in cancer treatments

Although adverse effects and glucocorticoid resistance cripple their chronic use, glucocorticoids form the mainstay therapy for acute and chronic inflammatory disorders, and play an important role in treatment protocols of both lymphoid malignancies and as adjuvant to stimulate therapy tolerability in various solid tumors. Glucocorticoid binding to their designate glucocorticoid receptor (GR), sets off a plethora of cell-specific events including therapeutically desirable effects, such as cell death, as well as undesirable effects, including chemotherapy resistance, systemic side effects and glucocorticoid resistance. In this context, selective GR agonists and modulators (SEGRAMs) with a more restricted GR activity profile have been developed, holding promise for further clinical development in anti-inflammatory and potentially in cancer therapies. Thus far, the research into the prospective benefits of selective GR modulators in cancer therapy limped behind. Our review discusses how selective GR agonists and modulators could improve the therapy regimens for lymphoid malignancies, prostate or breast cancer. We summarize our current knowledge and look forward to where the field should move to in the future. Altogether, our review clarifies novel therapeutic perspectives in cancer modulation via selective GR targeting

Latest perspectives on glucocorticoid-induced apoptosis and resistance in lymphoid malignancies

Glucocorticoids are essential drugs in the treatment protocols of lymphoid malignancies. These steroidal hormones trigger apoptosis of the malignant cells by binding to the glucocorticoid receptor (GR), which is a member of the nuclear receptor superfamily. Long term glucocorticoid treatment is limited by two major problems: the development of glucocorticoid-related side effects, which hampers patient quality of life, and the emergence of glucocorticoid resistance, which is a gradual process that is inevitable in many patients. This emphasizes the need to reevaluate and optimize the widespread use of glucocorticoids in lymphoid malignancies. To achieve this goal, a deep understanding of the mechanisms governing glucocorticoid responsiveness is required, yet, a recent comprehensive overview is currently lacking. In this review, we examine how glucocorticoids mediate apoptosis by detailing GR’s genomic and non-genomic action mechanisms in lymphoid malignancies. We continue with a discussion of the glucocorticoid-related problems and how these are intertwined with one another. We further zoom in on glucocorticoid resistance by critically analyzing the plethora of proposed mechanisms and highlighting therapeutic opportunities that emerge from these studies. In conclusion, early detection of glucocorticoid resistance in patients remains an important challenge as this would result in a timelier treatment reorientation and reduced glucocorticoid-instigated side effects

Neutrophil elastase is the 'histone H2A-specific protease'

Fundamental changes in the epigenetic status of histones from hematopoietic stem cells might be one of the driving forces behind many malignant transformations and subsequent leukemia development. The amino-terminal tail of histones and the carboxy-tail of histone H2A protrude from the nucleosome and can be modified by many different posttranslational modifications (PTM) on at least 60 different residues, thereby mediating chromatin dynamics. During an iTRAQ proteome analysis on Chronic Lymphocytic Leukemia (CLL) B-cells we came across a specific kind of histone modification that has received only little attention in epigenetics until now: histone clipping. The clipping of the histone H2A C-tail at V114 was more abundant in the CLL B-cell clones compared to healthy B-cells. This specific proteolytic product was already described in the context of leukemia in the late 70’s and is still being referenced today. To specifically quantify this clipping product, we developed and optimized a sensitive and high throughput AQUA approach, based on two isotopically labeled synthetic peptides. We screened 36 patients to investigate any discriminative power of clipped H2A as a potential prognostic marker. In doing so, we found that clipping mainly occurs in the myeloid lineage and has no clear link to the CLL B-cell clone. Here we show that the responsible enzyme, until now known as the “H2A specific protease”, but previously not identified, actually is Neutrophil Elastase. With the growing interest in the epigenetic potential of histone clipping we emphasize its potential role in hematopoietic differentiation

Effect of combining glucocorticoids with Compound A on glucocorticoid receptor responsiveness in lymphoid malignancies

Glucocorticoids (GCs) are a cornerstone in the treatment of lymphoid malignancies such as multiple myeloma (MM) and acute lymphoblastic leukemia (ALL). Yet, prolonged GC use is hampered by deleterious GC-related side effects and the emergence of GC resistance. To tackle and overcome these GC-related problems, the applicability of selective glucocorticoid receptor agonists and modulators was studied, in search of fewer side-effects and at least equal therapeutic efficacy as classic GCs. Compound A (CpdA) is a prototypical example of such a selective glucocorticoid receptor modulator and does not support GR-mediated transactivation. Here, we examined whether the combination of CpdA with the classic GC dexamethasone (Dex) may improve GC responsiveness of MM and ALL cell lines. We find that the combination of Dex and CpdA does not substantially enhance GC-mediated cell killing. In line, several apoptosis hallmarks, such as caspase 3/7 activity, PARP cleavage and the levels of cleaved-caspase 3 remain unchanged upon combining Dex with CpdA. Moreover, we monitor no additional inhibition of cell proliferation and the homologous downregulation of GR is not counteracted by the combination of Dex and CpdA. In addition, CpdA is unable to modulate Dex-liganded GR transactivation and transrepression, yet, Dex-mediated transrepression is also aberrant in these lymphoid cell lines. Together, transrepression-favoring compounds, alone or combined with GCs, do not seem a valid strategy in the treatment of lymphoid malignancies

Lipoprotein lipase SNPs rs13702 and rs301 correlate with clinical outcome in chronic lymphocytic leukemia patients

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and is characterized by a heterogeneous clinical course. This variability in clinical course has spiked the search for prognostic markers able to predict patient evolution at the moment of diagnosis. Markers demonstrated to be of value are the mutation status of the immunoglobulin heavy chain variable region genes (IGHV) and lipoprotein lipase (LPL) expression. High LPL mRNA expression has been associated with short treatment free (TFS) and decreased overall survival (OS) in CLL. The LPL SNPs rs301 (T<C), rs328 (C<G) and rs13702 (T<C) have been associated with various metabolic disorders, but the association with CLL evolution is unknown. Here, in a cohort of 248 patients, we show that patients with the LPL SNP rs13702 wild-type T/T genotype had significantly shorter OS than patients with C/C and T/C genotypes (median time until CLL related death: 90 and 156 months respectively, p=0.008). The same was observed for LPL SNP rs301 (median time until CLL related death T/T: 102 and C/C, T/C: 144 months, p=0.03). Both SNPs rs301 and rs13702 were significantly associated with each other and notably, no association was found between IGHV status and presence of the SNP genotypes, indicating that these LPL SNPs are reliable prognostic markers that could add extra prognostic and predictive information to classical markers and help to improve the management of CLL

Real world population-based exploration of the pathology subtyping and treatment-modalities of diffuse large B-cell lymphoma in Belgium in relation to survival

Background Up to now no real world data on the diagnostic work-up and treatments of diffuse large B-cell lymphoma (DLBCL) in Belgium were available. Aims To determine the patterns of care for DLBCL in Belgium with a specific focus on the elderly population, patients with comorbidities and other tumors (12%). Methods Coded data of all adult (≥ 20 year) DLBCL diagnosed 2013-2015 (n=1,890) were obtained via the Belgian Cancer Registry. Vital status was available until 1/7/2019. Data was extracted from pathology reports (10 biomarkers from IHC – FISH) and oncological care programs (performance status – staging). Treatments were inferred from health insurance data of reimbursed drugs. Information on HSCT and radiotherapy was based on nomenclature codes. An in-house algorithm was set up to define: Chemotherapy regimen (e.g. R-CHOP/R-DHAP) Number of cycles and cycle interval Switch between regimen Results Overall survival: The 2-year OS of all patients was 63.07% with a clear influence of age (30-84%). In contrast to the IPI using 60 as a cut-off, survival changed more markedly after the age of 70. Biomarkers: Pathology subtyping in 2013-2015 was missing information on now deemed essential biomarkers in 10-85% of cases. Of the evaluable cases, 49% were double expressors and 10% were double-hit DLBCL (FISH performed in only ±10%). No major differences were observed between age groups. Treatments: These varied significantly by age group and are displayed in Figure 1. Systemic treatment was started in 84%, decreasing with age to only 43%. Anthracycline based regimens were most frequently used, even in the elderly, and gold standard R-(mini)CHOP was associated with the best 4y-OS of 76%. Radiotherapy alone was frequently (5-13%) used in the elderly, and associated with a worse survival. Nonetheless the 4y-OS of 38% suggests a cure for selected patients. Second line treatments were mostly platinum based and survival without an option for autologous HSCT (ASCT) was poor (5y-OS 65% (ASCT) vs 11% (no-ASCT)). ASCT within 2 years from diagnosis was frequently performed in 1st line (n=32/67) and 3y-OS from start of ASCT in 1st, 2nd or further lines was similar (71%). Prognostic markers: Age seemed the most important prognostic factor (HR 1.94 to 5.7 for increasing age) on top of performance status (HR 3.74 if >1). Up to 12% had other malignancies with a worse prognosis (HR 2.00). Treatment with anthracycline containing regimens was associated with a better prognosis (HR 0,36 for ≥6 cycles of R-CHOP and HR 0,75 for other anthracycline containing regimens). Conclusion This real world population-based study allows to assess Belgian DLBCL patients usually excluded from clinical trials. Up to 28% of patients are ≥80 years old affecting treatment decisions and survival. The majority (63%) of older patients [70-84 yr-old] are started on anthracycline based treatments and seem to benefit from it

Glofitamab, a Novel, Bivalent CD20-Targeting T-Cell–Engaging Bispecific Antibody, Induces Durable Complete Remissions in Relapsed or Refractory B-Cell Lymphoma: A Phase I Trial

Glofitamab; B-Cell Lymphoma; RelapsedGlofitamab; Linfoma de células B; RecaídaGlofitamab; Limfoma de cèl·lules B; RecaigudaPURPOSE Glofitamab is a T-cell–engaging bispecific antibody possessing a novel 2:1 structure with bivalency for CD20 on B cells and monovalency for CD3 on T cells. This phase I study evaluated glofitamab in relapsed or refractory (R/R) B-cell non-Hodgkin lymphoma (B-NHL). Data for single-agent glofitamab, with obinutuzumab pretreatment (Gpt) to reduce toxicity, are presented. METHODS Seven days before the first dose of glofitamab (0.005-30 mg), all patients received 1,000 mg Gpt. Dose-escalation steps were determined using a Bayesian continuous reassessment method with overdose control. Primary end points were safety, pharmacokinetics, and the maximum tolerated dose of glofitamab. RESULTS Following initial single-patient cohorts, 171 patients were treated within conventional multipatient cohorts and received at least one dose of glofitamab. This trial included heavily pretreated patients with R/R B-NHL; most were refractory to prior therapy (155; 90.6%) and had received a median of three prior therapies. One hundred and twenty-seven patients (74.3%) had diffuse large B-cell lymphoma, transformed follicular lymphoma, or other aggressive histology, and the remainder had indolent lymphoma subtypes. Five (2.9%) patients withdrew from treatment because of adverse events. Cytokine release syndrome occurred in 86 of 171 (50.3%) patients (grade 3 or 4: 3.5%); two (1.2%) patients experienced grade 3, transient immune effector cell–associated neurotoxicity syndrome-like symptoms. The overall response rate was 53.8% (complete response [CR], 36.8%) among all doses and 65.7% (CR, 57.1%) in those dosed at the recommended phase II dose. Of 63 patients with CR, 53 (84.1%) have ongoing CR with a maximum of 27.4 months observation. CONCLUSION In patients with predominantly refractory, aggressive B-NHL, glofitamab showed favorable activity with frequent and durable CRs and a predictable and manageable safety profile

Coregulator profiling of the glucocorticoid receptor in lymphoid malignancies

Coregulators cooperate with nuclear receptors, such as the glucocorticoid receptor (GR), to enhance or repress transcription. These regulatory proteins are implicated in cancer, yet, their role in lymphoid malignancies, including multiple myeloma (MM) and acute lymphoblastic leukemia (ALL), is largely unknown. Here, we report the use and extension of the microarray assay for real-time nuclear receptor coregulator interactions (MARCoNI) technology to detect coregulator associations with endogenous GR in cell lysates. We use MARCoNI to determine the GR coregulator profile of glucocorticoid-sensitive (MM and ALL) and glucocorticoid-resistant (ALL) cells, and identify common and unique coregulators for different cell line comparisons. Overall, we identify SRC-1/2/3, PGC-1 alpha, RIP140 and DAX-1 as the strongest interacting coregulators of GR in MM and ALL cells and show that the interaction strength does not correlate with GR protein levels. Lastly, as a step towards patient samples, we determine the GR coregulator profile of peripheral blood mononuclear cells. We profile the interactions between GR and coregulators in MM and ALL cells and suggest to further explore the GR coregulator profile in hematological patient samples

Quantitative proteomics to characterize specific histone H2A proteolysis in chronic lymphocytic leukemia and the myeloid THP-1 cell line

Proteome studies on hematological malignancies contribute to the understanding of the disease mechanism and to the identification of new biomarker candidates. With the isobaric tag for relative and absolute quantitation (iTRAQ) method we analyzed the protein expression between B-cells of healthy people and chronic lymphocytic leukemia (CLL) B-cells. CLL is the most common lymphoid cancer of the blood and is characterized by a variable clinical course. By comparing samples of patients with an aggressive vs. indolent disease, we identified a limited list of differentially regulated proteins. The enhanced sensitivity attributed to the iTRAQ labels led to the discovery of a previously reported but still not clarified proteolytic product of histone H2A (cH2A) which we further investigated in light of the suggested functional properties of this modification. In the exploratory proteome study the Histone H2A peptide was up-regulated in CLL samples but a more specific and sensitive screening of a larger patient cohort indicated that cH2A is of myeloid origin. Our subsequent quantitative analysis led to a more profound characterization of the clipping in acute monocytic leukemia THP-1 cells subjected to induced differentiation