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Acute leukemia (AL) with a lineage switch (LS) is associated with poor prognosis. The predisposing factors of LS are unknown, apart from KMT2A rearrangements that have been reported to be associated with LS. Herein, we present two cases and review all 104 published cases to identify risk factors for LS. Most of the patients (75.5%) experienced a switch from the lymphoid phenotype to the myeloid phenotype. Eighteen patients (17.0%) experienced a transformation from acute myelogenous leukemia (AML) to acute lymphoblastic leukemia (ALL). Forty-nine (46.2%) patients carried a KMT2A rearrangement. Most of the cases involved LS from B-cell ALL (B-ALL) to AML (59.4%), and 49 patients (46.2%) carried KMT2A-rearrangements. Forty patients (37.7%) received lineage-specific immunotherapy. Our findings suggest that the prevalence of KMT2A rearrangements together with the lineage-specific immunotherapy may trigger LS, which supports the thesis of the existence of leukemia stem cells that are capable of lymphoid or myeloid differentiation. [ABSTRACT FROM AUTHOR]

Simple Summary: Therapeutic anti-CD20 monoclonal antibodies (mAbs) are divided into two types based on their dominant effector mechanism. In contrast to type I specimens, obinutuzumab, a representative of type II mAbs, poorly activates the complement system. Recent studies explained that the structure of the antigen–antibody complex characteristic for type II antibodies precludes oligomer formation, which otherwise supports an efficient complement activation by human mAbs. Herein, we provide evidence that obinutuzumab's ability to activate complement can be rescued at later stages of the cascade, as observed in the presence of hyperactive complement convertase components. Such modulation, which enforces additional effector mechanisms, may be an alternative way of improving a killing repertoire of already existing drugs rather than designing their novel versions. Rituximab, a prototypic anti-CD20 mAb, and the third-generation anti-CD20 mAb obinutuzumab differ in their ability to activate the complement system. According to recent studies, this contrast stems from the architecture of the antigen–antibody complex formed by these two mAbs that facilitates (rituximab) or disables (obinutuzumab) further oligomerization, leading to engagement of the initial classical complement pathway component C1q. We examined whether a gain-of-function C2 variant that acts downstream of C1q and enforces the formation of complement convertase resistant to physiological decay can impact complement activation by obinutuzumab. Co-application of the C2 variant with obinutuzumab and human serum resulted in complement-dependent cytotoxicity equal to or higher than attainable for rituximab. This effect was observed either in serum or hirudin-anticoagulated whole blood. Long-term (24 h) overall cytotoxicity of obinutuzumab was improved in target cells of moderate sensitivity to complement but diminished in cells of low sensitivity. Our results demonstrate that the ability of complement activation of a given antibody is not ultimately determined at the stage of initial interactions with its target antigen but is modulable at later stages of the cascade and that the benefit of the acquisition of this new effector mechanism by obinutuzumab depends on the target cell characteristics. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor T (CAR-T) cells are specifically modified T cells which bear recombinant receptors, present at the cell surface and devoted to detect selected antigens of cancer cells, and due to the presence of transmembrane and activation domains, able to eliminate the latter ones. The use of CAR-T cells in anti-cancer therapies is a relatively novel approach, providing a powerful tool in the fight against cancer and bringing new hope for patients. However, despite huge possibilities and promising results of preclinical studies and clinical efficacy, there are various drawbacks to this therapy, including toxicity, possible relapses, restrictions to specific kinds of cancers, and others. Studies desiring to overcome these problems include various modern and advanced methods. One of them is transcriptomics, a set of techniques that analyze the abundance of all RNA transcripts present in the cell at certain moment and under certain conditions. The use of this method gives a global picture of the efficiency of expression of all genes, thus revealing the physiological state and regulatory processes occurring in the investigated cells. In this review, we summarize and discuss the use of transcriptomics in studies on and applications of CAR-T cells, especially in approaches focused on improved efficacy, reduced toxicity, new target cancers (like solid tumors), monitoring the treatment efficacy, developing novel analytical methods, and others. [ABSTRACT FROM AUTHOR]

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The study explains the characterization, symptoms and the mutations associated with the Diamond-Blackfan anemia (DBA), a congenital bone-marrow-failure syndrome. The ribosomal protein L5 and L11 mutations are shown to be associated with cleft palate and abnormal thumbs in the DBA patients.

Summary: The standard of care for indolent non‐Hodgkin lymphoma (iNHL) is rituximab, an anti‐CD20 antibody, with/without chemotherapy. However, multiple relapses are common in these patients. This phase 3, randomized study compared outcomes of a combination of ofatumumab (a second‐generation anti‐CD20 antibody) and bendamustine, with bendamustine alone in patients unresponsive to prior rituximab‐based treatment. Overall, 346 patients were randomized to receive either the combination or bendamustine alone. Bendamustine was given for ≤8 cycles and ofatumumab for ≤12 cycles. The primary end‐point was progression‐free survival (PFS) after 215 protocol‐defined events assessed by independent review committee (IRC). Median IRC‐assessed PFS was 16·7 and 13·8 months in the combination and monotherapy arms respectively [hazard ratio (HR) = 0·82; P = 0·1390]. Median overall survival (OS) was 58·2 and 51·8 months in the combination and monotherapy arms respectively (HR = 0·89, P = 0·4968). The safety profile was consistent with previous reports. Overall, 73% and 80% of patients in the combination and monotherapy arms, respectively, experienced a ≥grade 3 adverse event. The study did not meet its primary end‐point. No significant improvement in PFS and OS was seen with the combination of ofatumumab and bendamustine as compared with bendamustine alone in rituximab‐refractory iNHL (NCT01077518). [ABSTRACT FROM AUTHOR]

Rituximab is a pioneering anti-CD20 monoclonal antibody that became the first-line drug used in immunotherapy of B-cell malignancies over the last twenty years. Rituximab activates the complement system in vitro , but there is an ongoing debate on the exact role of this effector mechanism in therapeutic effect. Results of both in vitro and in vivo studies are model-dependent and preclude clear clinical conclusions. Additional confounding factors like complement inhibition by tumor cells, loss of target antigen and complement depletion due to excessively applied immunotherapeutics, intrapersonal variability in the concentration of main complement components and differences in tumor burden all suggest that a personalized approach is the best strategy for optimization of rituximab dosage and therapeutic schedule. Herein we critically review the existing knowledge in support of such concept and present original data on markers of complement activation, complement consumption, and rituximab accumulation in plasma of patients with chronic lymphocytic leukemia (CLL) and non-Hodgkin's lymphomas (NHL). The increase of markers such as C4d and terminal complement complex (TCC) suggest the strongest complement activation after the first administration of rituximab, but not indicative of clinical outcome in patients receiving rituximab in combination with chemotherapy. Both ELISA and complement-dependent cytotoxicity (CDC) functional assay showed that a substantial number of patients accumulate rituximab to the extent that consecutive infusions do not improve the cytotoxic capacity of their sera. Our data suggest that individual assessment of CDC activity and rituximab concentration in plasma may support clinicians' decisions on further drug infusions, or instead prescribing a therapy with anti-CD20 antibodies like obinutuzumab that more efficiently activate effector mechanisms other than complement. [ABSTRACT FROM AUTHOR]

Summary: R‐CVP (cyclophosphamide, vincristine, prednisone) and R‐CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone + rituximab) are immunochemotherapy regimens frequently used for remission induction of indolent non‐Hodgkin lymphomas (iNHLs). Rituximab maintenance (RM) significantly improves progression‐free survival (PFS) in patients with complete/partial remission (CR/PR). Here we report the final results of a randomized study comparing R‐CVP to R‐CHOP both followed by RM. Untreated patients in need of systemic therapy with symptomatic and progressive iNHLs including follicular (FL) and marginal zone lymphoma (MZL), mucosa‐associated lymphoid tissue (MALT), small lymphocytic (SLL), and lymphoplasmacytic (LPL) lymphoma were eligible. Patients were randomized to receive R‐CVP or R‐CHOP for eight cycles or until complete response (CR). All patients with CR/PR (partial response) received RM 375 mg/m2 q 2 months for 12 cycles. Primary endpoint was event‐free survival (EFS). Two‐hundred and fifty patients [FL 42%, MZL/MALT 38%, LPL/ Waldenström Macroglobulinaemia (WM) 11%, SLL 9%] were enrolled and randomized (R‐CHOP: 127, R‐CVP: 123). Median age was 56 years (21–85), 44% were male, 90% were in stage III–IV, 43% of FL patients had a Follicular Lymphoma International Prognostic Index (FLIPI) score ≥3, and 33·4% of all patients had an IPI score ≥3. At the end of induction treatment, the CR/PR rate was 43·6/50·9% and 36·3/60·8% in the R‐CHOP and R‐CVP groups (P = 0·218) respectively. After a median follow‐up of 67, 66, and 70 months, five‐year EFS was 61% vs. 56% (not significant), progression‐free survival (PFS) was 71% vs. 69% (not significant) and overall survival (OS) was 84% vs. 89% in the R‐CHOP vs. the R‐CVP arm respectively. Grade III/IV adverse events (65 vs. 22) occurred in 40 (33·1%) and 18 (15·3%) patients, P = 0·001; neutropenia in 16 (11·6%) and 4 (3·4%) patients, P = 0·017; infection in 14 (10·7%) and 3 (2·5%) patients,; P = 0·011; and a second neoplasm in three versus seven patients., in the R‐CHOP and the R‐CVP groups respectively. This multicentre randomized study with >five‐year follow‐up shows similar outcome in patients with indolent lymphoma in need of systemic therapy treated with R‐CVP or R‐CHOP immunochemotherapy and rituximab maintenance in both arms. The minor toxicity of the R‐CVP regimen makes it a reasonable choice for induction treatment, leaving other active agents like doxorubicin or bendamustin for second‐line therapy. [ABSTRACT FROM AUTHOR]

We compared initial computed tomography (CT) and positron emission tomography (PET)/CT in 96 patients with Hodgkin lymphoma (HL), assessing the role of baseline PET/CT in stage migration and treatment selection. The number of patients with stage I, II, III and IV disease based on CT versus PET/CT was: 5 vs. 7, 49 vs. 37, 28 vs. 22 and 14 vs. 30, respectively. In 33 (34%) patients, PET/CT changed HL stage: 27 (28%) were upstaged and six (6.3%) downstaged. Upstaging was caused by detection of new extranodal involvements (47 sites in 26 patients): bone marrow (10 patients), spleen (five patients) and lung (two patients). In nine patients ≥ 2 further coexisting locations were detected. Downstaging resulted from the absence of fluorodeoxyglucose (18F-FDG) uptake in enlarged nodes (> 15 mm) in the abdomen and pelvis. PET/CT modified HL stage in 34% of patients leading to treatment modification in the majority. Our results indicate that PET/CT should be mandatory in the initial staging of HL. [ABSTRACT FROM AUTHOR]

Simple Summary: The complement system can be exploited by anticancer antibody-based therapeutics. Activation of the classical complement pathway by the heavy chain of antibodies eventually leads to the lysis of target cells. However, overexpression of complement inhibitors by tumor cells limits the therapeutic efficacy. We designed and produced recombinant gain-of-function variants of complement C2 protein that counteract the activity of complement inhibitors. The dominant character of designed mutations in C2 allows supplementation of human serum with recombinant proteins for enhancing the cytocidal activity of complement-activating antibodies. In vitro functional assays demonstrate that this strategy is compatible with several clinically approved antibodies. The molecular target for the classical complement pathway (CP) is defined by surface-bound immunoglobulins. Therefore, numerous anticancer monoclonal antibodies (mAbs) exploit the CP as their effector mechanism. Conversely, the alternative complement pathway (AP) is spontaneously induced on the host and microbial surfaces, but complement inhibitors on host cells prevent its downstream processing. Gain-of-function (GoF) mutations in the AP components that oppose physiological regulation directly predispose carriers to autoimmune/inflammatory diseases. Based on the homology between AP and CP components, we modified the CP component C2 so that it emulates the known pathogenic mutations in the AP component, factor B. By using tumor cell lines and patient-derived leukemic cells along with a set of clinically approved immunotherapeutics, we showed that the supplementation of serum with recombinant GoF C2 variants not only enhances the cytocidal effect of type I anti-CD20 mAbs rituximab and ofatumumab, but also lowers the threshold of mAbs necessary for the efficient lysis of tumor cells and efficiently exploits the leftovers of the drug accumulated in patients' sera after the previous infusion. Moreover, we demonstrate that GoF C2 acts in concert with other therapeutic mAbs, such as type II anti-CD20, anti-CD22, and anti-CD38 specimens, for overcoming cancer cells resistance to complement attack. [ABSTRACT FROM AUTHOR]

Diamond-Blackfan anemia (DBA) is a broad developmental disease characterized by anemia, bone marrow (BM) erythroblastopenia, and an increased incidence of malignancy. Mutations in ribosomal protein gene S19 (RPS19) are found in ∼25% of DBA patients; however, the role of RPS19 in the pathogenesis of DBA remains unknown. Using global gene expression analysis, we compared highly purified multipotential, erythroid, and myeloid BM progenitors from RPS19 mutated and control individuals. We found several ribosomal protein genes downregulated in all DBA progenitors. Apoptosis genes, such as TNFRSF10B and FAS, transcriptional control genes, including the erythropoietic transcription factor MYB (encoding c-myb), and translational genes were greatly dysregulated, mostly in diseased erythroid cells. Cancer-related genes, including RAS family oncogenes and tumor suppressor genes, were significantly dysregulated in all diseased progenitors. In addition, our results provide evidence that RPS19 mutations lead to codownregulation of multiple ribosomal protein genes, as well as downregulation of genes involved in translation in DBA cells. In conclusion, the altered expression of cancer-related genes suggests a molecular basis for malignancy in DBA. Downregulation of c-myb expression, which causes complete failure of fetal liver erythropoiesis in knockout mice, suggests a link between RPS19 mutations and reduced erythropoiesis in DBA. [ABSTRACT FROM AUTHOR]

Glofitamab monotherapy induces durable remission in patients with relapsed or refractory diffuse large B-cell lymphoma after two or more previous therapies, but has not previously been assessed as a second-line therapy. We investigated the efficacy and safety of glofitamab plus gemcitabine–oxaliplatin (Glofit-GemOx) versus rituximab (R)-GemOx in patients with relapsed or refractory diffuse large B-cell lymphoma. The phase 3, randomised, open-label STARGLO trial was done at 62 centres in 13 countries in Asia and Australia, Europe, and North America. We recruited transplant-ineligible patients (aged ≥18 years) with histologically confirmed relapsed or refractory diffuse large B-cell lymphoma after one or more previous therapies. Patients were randomly assigned in permuted blocks (block size of six) via an interactive voice or web response system (2:1; stratified by 1 vs ≥2 previous lines of therapy and relapsed vs refractory status) to Glofit-GemOx (intravenous gemcitabine 1000 mg/m2 and oxaliplatin 100 mg/m2 plus glofitamab step-up dosing to 30 mg; for a total of eight cycles, plus four additional cycles of glofitamab monotherapy) or R-GemOx (intravenous gemcitabine 1000 mg/m2 and oxaliplatin 100 mg/m2 plus rituximab 375 mg/m2; for a total of eight cycles). The trial independent review committee, which evaluated all response-based endpoints, was masked to treatment assignment. The primary endpoint was overall survival. Efficacy analyses were by intention to treat in all randomly assigned patients. We present results from both the primary analysis (cutoff: March 29, 2023) and updated analysis after all patients had completed study therapy (cutoff: Feb 16, 2024). Safety analyses included all patients who received any study treatment. This study is registered with ClinicalTrials.gov , NCT04408638 , and is ongoing (closed to recruitment). From Feb 23, 2021, to March 14, 2023, 274 patients were enrolled and randomly assigned to receive Glofit-GemOx (n=183) or R-GemOx (n=91). 158 (58%) patients were male and 116 (42%) were female; median age was 68 years (IQR 58–74). At the primary analysis after a median follow-up of 11·3 months (95% CI 9·6–12·7), overall survival was significantly improved with Glofit-GemOx versus R-GemOx (median not estimable [NE; 95% CI 13·8 months–NE] vs 9·0 months [7·3–14·4]; hazard ratio [HR] 0·59 [95% CI 0·40–0·89]; p=0·011). At the updated analysis after a median follow-up of 20·7 months (19·9–23·3), a consistent improvement in overall survival was observed with Glofit-GemOx versus R-GemOx (median 25·5 months [18·3–NE] vs 12·9 months [7·9–18·5]; HR 0·62 [0·43–0·88]). In the safety sets, 180 (100%) patients in the Glofit-GemOx group and 84 (96%) of 88 patients in the R-GemOx group had at least one adverse event during the study period. Cytokine release syndrome occurred in 76 (44%) of 172 glofitamab-exposed patients and was predominantly low grade. Deaths related to glofitamab or rituximab occurred in five (3%) patients in the Glofit-GemOx group and in one (1%) patient in the R-GemOx group. Glofit-GemOx had a significant overall survival benefit compared with R-GemOx, supporting its use in transplant-ineligible patients with relapsed or refractory diffuse large B-cell lymphoma after one or more previous lines of therapy. F Hoffmann-La Roche. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about the declaration of thymoma-related pure red cell aplasia after octreotide treatment.