Proteasome inhibition overcomes resistance to targeted therapies in B-cell malignancy models and in an index patient.

Treatment of B-cell malignancies with the PI3K inhibitor (PI3Ki) idelalisib often results in high toxicity and resistance, with limited treatment alternatives for relapsed/refractory patients since idelalisib is recommended as a later or last line therapy. To investigate resistance mechanisms and identify alternative treatments, we studied functional phenotypes of idelalisib-resistant B-cell malignancy models. The idelalisib-resistant KARPAS1718 model remained sensitive to Bcl-2 inhibitors (Bcl-2i), whereas the resistant VL51 model showed reduced sensitivity compared to parental cells.

A predictive serum miRNA signature impacts diffuse large B-cell lymphoma cell viability via inhibition of EGLN1 and TXNRD1 regulators of ferroptosis.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disorder. Prognostic factors include genomic alterations and cell-of-origin (COO) subtypes, even though they cannot fully predict treatment response. MicroRNAs (miRNAs) deregulated in patient tumours and blood are promising non-invasive biomarkers.

IL-16 production is a mechanism of resistance to BTK inhibitors and R-CHOP in lymphomas.

Introducing Bruton's tyrosine kinase (BTK) inhibitors has significantly improved outcomes for patients with B-cell malignancies and autoimmune disorders. However, resistance, either primary or acquired, remains a major clinical challenge. To better understand the underlying resistance mechanisms to BTK inhibitors, we established an ibrutinib-resistant model from a patient-derived splenic marginal zone lymphoma (MZL) cell line (VL51) through prolonged drug exposure.

Chemosensor receptors are lipid-detecting regulators of macrophage function in cancer.

Infiltration of macrophages into tumors is a hallmark of cancer progression, and re-educating tumor-associated macrophages (TAMs) toward an antitumor status is a promising immunotherapy strategy. However, the mechanisms through which cancer cells affect macrophage education are unclear, limiting the therapeutic potential of this approach. Here we conducted an unbiased genome-wide CRISPR screen of primary macrophages.

KAT/3BP: A Metabolism-Targeting Agent with Single and Combination Activity in Aggressive B-Cell Lymphomas.

Background/objectives: Reprogramming of the cellular metabolism is a hallmark of cancer, offering therapeutic opportunities to target cancer cell vulnerabilities for therapeutic purposes. 3-Bromopyruvate (3BP) is a small alkylating agent that functions as an anti-metabolite, targeting key substrates in cancer metabolism and demonstrating antitumor activity across multiple cancer types. However, unformulated 3BP is associated with significant toxicity.

Novel Flavonoid Derivatives Show Potent Efficacy in Human Lymphoma Models.

Background: Despite significant therapeutic progress, many lymphoma subtypes remain difficult to manage due to resistance, relapse, and dose-limiting toxicity.

Methods: To elucidate the mechanism of action of the semi-synthetic flavonoid derivative (SND) compounds, we conducted a screening of cancer cell lines using proliferation, cell cycle, and apoptosis assays. We then performed computational modeling of the compounds' binding to tubulin, and finally evaluated in vivo activity using nanoNail technology alongside xenograft experiment.

Novel PI3kδ inhibitor roginolisib synergizes with venetoclax in hematologic malignancies.

The phosphoinositide 3-kinase (PI3K) pathway remains a potent drug target in hematological malignancies despite the challenges that have affected clinical drug development, particularly unpredictable toxicity, and inherent/acquired drug resistance. Herein, we tested the activity of a novel PI3Kδ selective, non-ATP competitive inhibitor, roginolisib (IOA-244), in hematological malignancies including diffuse large B cell lymphoma (DLBCL) and chronic lymphocytic leukemia (CLL). To identify rational actionable combination partners that can be tested in hematologic malignancies, an unbiased pharmacological screening of 474 compounds was carried out in two lymphoma cell lines.

Development of C646-Based Proteolysis Targeting Chimeras Degraders of the Lysine Acetyltransferases CBP and p300.

The alteration of the lysine acetyltransferase activity and protein-protein interactions of the transcriptional co-activators CREB-binding protein (CBP) and p300 is linked to the development of both solid and hematological cancers. To target both functions of CBP/p300, two PROTAC-based chemical degraders are developed by linking the CBP/p300 catalytic inhibitor C646 and the Cereblon (CRBN) ligand thalidomide via polyethylene glycol-based linkers. Both compounds exhibit submicromolar inhibition of CBP/p300 and decrease their levels in the SU-DHL-10 lymphoma cell line at low-micromolar concentrations.

A patient-derived T cell lymphoma biorepository uncovers pathogenetic mechanisms and host-related therapeutic vulnerabilities.

Peripheral T cell lymphomas (PTCLs) comprise heterogeneous malignancies with limited therapeutic options. To uncover targetable vulnerabilities, we generate a collection of PTCL patient-derived tumor xenografts (PDXs) retaining histomorphology and molecular donor-tumor features over serial xenografting. PDX demonstrates remarkable heterogeneity, complex intratumor architecture, and stepwise trajectories mimicking primary evolutions.

FLI1 Induces Plaque Psoriasis and Its Inhibition Attenuates Disease Progression.

Plaque Psoriasis: Plaque psoriasis is an inflammatory skin disorder affecting nearly 2% of the world population. Despite recent advances in psoriasis treatment, there is still a need for more effective therapies. The ETS transcription factor FLI1 plays critical roles in hematopoiesis, angiogenesis, immunity, and cancer.

Targeting of PIM Kinases Shows Single Agent Efficacy and Synergizes With BCL2 Inhibitors in Diffuse Large B Cell Lymphoma of the ABC Subtype.

The PIM family of serine/threonine kinases (PIM1, PIM2, and PIM3) are involved in the development of cancer and represent promising therapeutic targets. We investigated the therapeutic potential of targeting PIM kinases in diffuse large B-cell lymphoma (DLBCL), particularly the activated B-cell-like (ABC) subtype, using the pan-PIM inhibitor AZD1208. We demonstrated that PIM1 and PIM2 are more highly expressed in ABC- cells than in germinal center B-cell-like (GCB) -DLBCL cells, and that ABC-DLBCL cell lines are more sensitive to PIM inhibition with AZD1208.

EasyCircR: Detection and reconstruction of circular RNAs post-transcriptional regulatory interaction networks.

Circular RNAs (circRNAs) are regulatory RNAs that play a crucial role in various biological activities and have been identified as potential biomarkers for neurological disorders and cancer. CircRNAs have emerged as significant regulators of gene expression through different mechanisms, including regulation of transcription and splicing, modulation of translation, and post-translational modifications. Additionally, some circRNAs operate as microRNA (miRNA) sponges in the cytoplasm, boosting post-transcriptional expression of target genes by inhibiting miRNA activity.

The K9 lymphoma assay allows a genetic subgrouping of canine lymphomas with improved risk classification.

We present here the K9 lymphoma assay, a novel 31-gene targeted next-generation sequencing panel designed for genomic profiling of canine lymphoid neoplasms. Addressing the growing demand for advanced diagnostics in veterinary oncology, this assay enables sensitive identification of known and actionable mutations specific to canine lymphomas, while evaluating its prognostic potential to facilitate diagnosis and prognosis. Our analysis, spanning several B- and T-cell lymphoma histotypes, unveiled distinct mutational landscapes distinguishing tumors derived from immature versus mature lymphocytes.

Targeting CD25+ lymphoma cells with the antibody-drug conjugate camidanlumab tesirine as a single agent or in combination with targeted agents.

Camidanlumab tesirine (ADCT-301) is a CD25-specific antibody-drug conjugate (ADC) employing SG3199, a highly cytotoxic DNA minor groove cross-linking pyrrolobenzodiazepine dimer. The ADC has shown early clinical antitumour activity in various cancers, including B- and T-cell lymphomas. We assessed its preclinical activity as a single agent in 57 lymphoma cell lines and in combination with selected drugs in T-cell lymphoma-derived cell lines.

Selective haematological cancer eradication with preserved haematopoiesis.

Haematopoietic stem cell (HSC) transplantation (HSCT) is the only curative treatment for a broad range of haematological malignancies, but the standard of care relies on untargeted chemotherapies and limited possibilities to treat malignant cells after HSCT without affecting the transplanted healthy cells. Antigen-specific cell-depleting therapies hold the promise of much more targeted elimination of diseased cells, as witnessed in the past decade by the revolution of clinical practice for B cell malignancies. However, target selection is complex and limited to antigens expressed on subsets of haematopoietic cells, resulting in a fragmented therapy landscape with high development costs.

Targeting CD19-positive lymphomas with the antibodydrug conjugate loncastuximab tesirine: preclinical evidence of activity as a single agent and in combination therapy.

Antibody-drug conjugates (ADC) represent one of the most successful therapeutic approaches introduced into clinical practice in the last few years. Loncastuximab tesirine (ADCT-402) is a CD19-targeting ADC in which the antibody is conjugated through a protease cleavable dipeptide linker to a pyrrolobenzodiazepine dimer warhead (SG3199). Based on the results of a phase II study, loncastuximab tesirine was recently approved for adult patients with relapsed/refractory large B-cell lymphoma.

IELSG38: phase II trial of front-line chlorambucil plus subcutaneous rituximab induction and maintenance in mucosa-associated lymphoid tissue lymphoma.

The IELSG38 trial was conducted to investigate the effects of subcutaneous (SC) rituximab on the complete remission (CR) rate and the benefits of SC rituximab maintenance in patients with extranodal marginal zone lymphoma (MZL) who received front-line treatment with chlorambucil plus rituximab. Study treatment was an induction phase with oral chlorambucil 6 mg/m2/day on weeks 1-6, 9-10, 13-14, 17-18, and 21-22, and intravenous rituximab 375 mg/m2 on day 1 of weeks 1-4, and 1,400 mg SC on weeks 9, 13, 17, and 21. Then, a maintenance phase followed with rituximab administered at 1,400 mg SC every two months for two years.

ADCT-602, a Novel PBD Dimer-containing Antibody-Drug Conjugate for Treating CD22-positive Hematologic Malignancies.

Relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) and lymphomas have poor patient outcomes; novel therapies are needed. CD22 is an attractive target for antibody-drug conjugates (ADCs), being highly expressed in R/R B-ALL with rapid internalization kinetics. ADCT-602 is a novel CD22-targeting ADC, consisting of humanized mAb hLL2-C220, site specifically conjugated to the pyrrolobenzodiazepine dimer-based payload tesirine.

ERBB4-Mediated Signaling Is a Mediator of Resistance to PI3K and BTK Inhibitors in B-cell Lymphoid Neoplasms.

BTK and PI3K inhibitors are among the drugs approved for the treatment of patients with lymphoid neoplasms. Although active, their ability to lead to long-lasting complete remission is rather limited, especially in the lymphoma setting. This indicates that tumor cells often develop resistance to the drugs.

PI3Kδ activation, IL6 over-expression, and CD37 loss cause resistance to the targeting of CD37-positive lymphomas with the antibody-drug conjugate naratuximab emtansine.

Purpose: The transmembrane protein CD37 is expressed almost exclusively in lymphoid tissues, with the highest abundance in mature B cells. CD37-directed antibody- and, more recently, cellular-based approaches have shown preclinical and promising early clinical activity. Naratuximab emtansine (Debio 1562, IMGN529) is an antibodydrug conjugate (ADC) that incorporates an anti-CD37 monoclonal antibody conjugated to the maytansinoid DM1 as payload.

The ATR inhibitor elimusertib exhibits anti-lymphoma activity and synergizes with the PI3K inhibitor copanlisib.

The DNA damage response (DDR) is the cellular process of preserving an intact genome and is often deregulated in lymphoma cells. The ataxia telangiectasia and Rad3-related (ATR) kinase is a crucial factor of DDR in the response to DNA single-strand breaks. ATR inhibitors are agents that have shown considerable clinical potential in this context.

How to integrate CD19 specific chimeric antigen receptor T cells with other CD19 targeting agents in diffuse large B-cell lymphoma?

About one third of patients with diffuse large B-cell lymphoma (DLBCL) have a relapsing/refractory (R/R) disease after first line chemo-immunotherapy, with particularly poor outcomes observed in patients with primary refractory disease and early relapse. CD19 specific chimeric antigen receptor (CAR) T cell therapy is a game changer that results in durable and complete response rates in almost half of the patients with R/R DLBCL. Other emerging CD19-targeting therapies include monoclonal antibodies, bispecific antibodies and targeting antibody-drug conjugates, which also show encouraging results.