Chimeric Antigen Receptor-Modified T Cell Immunotherapy for Relapsed and Refractory Adult Burkitt Lymphoma

Refractory Burkitt Lymphoma: Diagnosis and Interventional Strategies

Despite excellent results in frontline therapy, particularly in pediatric age, refractory Burkitt lymphoma still remains a therapeutic challenge, with dismal outcome. The prognosis is very poor, ranging from less than 10% to 30-40%, with longer survival only in transplanted patients. On account of the paucity of data, mostly reporting on small series of patients, with heterogeneous characteristics and salvage treatments, at present it is impossible to draw definitive conclusions on the treatment of choice for this difficult to treat subset of patients. New insights into Burkitt lymphoma/leukemia cell biology have led to the development of new drugs, currently being tested, directed at different specific targets. Herein, we describe the results so far reported in refractory Burkitt lymphoma/leukemia, with standard treatments and hematopoietic stem cell transplant, and we review the new targeted drugs currently under evaluation.

Network and Computational Drug Repurposing Analysis for c-Myc Inhibition in Burkitt Lymphoma

BACKGROUND/AIM

The treatment rate of Burkitt lymphoma (BL) is still low in low-income countries and among elderly patients. The c-Myc dysregulation induced by mutations is one of the characteristics of BL. However, studies on the downstream signaling pathways of c-Myc are still lacking. This study aimed to identify the signaling pathways regulated by c-Myc.

MATERIALS AND METHODS

Network and gene set analyses using c-Myc inhibition (i.e., c-Myc knock-down and c-Myc inhibitor treatment) transcriptome datasets for BL cell lines were performed to determine the pathways regulated by c-Myc. In addition, computational drug repurposing was used to identify drugs that can regulate c-Myc downstream signaling pathway.

RESULTS

Computational drug repurposing revealed that the ERK/MAPK signaling pathway is regulated by c-Myc in BL and that this pathway can be modulated by vorinostat. Furthermore, in the pharmacogenomics database, vorinostat showed a cell viability half-maximal inhibitory concentration of less than 2 μM in the BL cell lines.

CONCLUSION

The downstream signaling pathway regulated by c-Myc and the drug that can modulate this pathway is presented for the first time.

Broadening the horizon: potential applications of CAR-T cells beyond current indications

Engineering immune cells to treat hematological malignancies has been a major focus of research since the first resounding successes of CAR-T-cell therapies in B-ALL. Several diseases can now be treated in highly therapy-refractory or relapsed conditions. Currently, a number of CD19- or BCMA-specific CAR-T-cell therapies are approved for acute lymphoblastic leukemia (ALL), diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), multiple myeloma (MM), and follicular lymphoma (FL). The implementation of these therapies has significantly improved patient outcome and survival even in cases with previously very poor prognosis. In this comprehensive review, we present the current state of research, recent innovations, and the applications of CAR-T-cell therapy in a selected group of hematologic malignancies. We focus on B- and T-cell malignancies, including the entities of cutaneous and peripheral T-cell lymphoma (T-ALL, PTCL, CTCL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), classical Hodgkin-Lymphoma (HL), Burkitt-Lymphoma (BL), hairy cell leukemia (HCL), and Waldenström's macroglobulinemia (WM). While these diseases are highly heterogenous, we highlight several similarly used approaches (combination with established therapeutics, target depletion on healthy cells), targets used in multiple diseases (CD30, CD38, TRBC1/2), and unique features that require individualized approaches. Furthermore, we focus on current limitations of CAR-T-cell therapy in individual diseases and entities such as immunocompromising tumor microenvironment (TME), risk of on-target-off-tumor effects, and differences in the occurrence of adverse events. Finally, we present an outlook into novel innovations in CAR-T-cell engineering like the use of artificial intelligence and the future role of CAR-T cells in therapy regimens in everyday clinical practice.

CAR-T Cell Therapy in the Treatment of Pediatric Non-Hodgkin Lymphoma

Non-Hodgkin lymphomas (NHL) are a group of cancers that originate in the lymphatic system, especially from progenitor or mature B-cells, T-cells, or natural killer (NK) cells. NHL is the most common hematological malignancy worldwide and also the fourth most frequent type of cancer among pediatric patients. This cancer can occur in children of any age, but it is quite rare under the age of 5 years. In recent decades, available medicines and therapies have significantly improved the prognosis of patients with this cancer. However, some cases of NHL are treatment resistant. For this reason, immunotherapy, as a more targeted and personalized treatment strategy, is becoming increasingly important in the treatment of NHL in pediatric patients. The objective of the following review is to gather the latest available research results, conducted among pediatric and/or adult patients with NHL, regarding one immunotherapy method, i.e., chimeric antigen receptor (CAR) T cell therapy. We focus on assessing the effectiveness of CAR-T cell therapy, which mainly targets B cell markers, CD19, CD20, and CD22, their connections with one another, sequential treatment, or connections with co-stimulatory molecules. In addition, we also evaluate the safety, aftermath (especially neurotoxicities) and limitations of CAR-T cell therapy.

Bone Marrow Aplasia after CAR-T-Cell Therapy for Relapsed/Refractory Burkitt's Lymphoma

Chimeric antigen receptor T-cells (CAR-T) are now a standard approach for treating relapsed/refractory B-cell lymphomas. Immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome (IEC-HS) is a newly described entity that can manifest following CAR-T. Bone marrow (BM) aplasia is an uncommon manifestation of IEC-HS reported after CAR-T-cell therapy and is defined as the reduction or absence of hematopoietic progenitor cells resulting in severe pancytopenia. We describe the case of a 44-year-old female with relapsed/refractory Burkitt lymphoma (BL) who received treatment with lisocabtagene maraleucel with her post-CAR-T course complicated by cytokine release syndrome (CRS) and IEC-HS ultimately leading to persistent BM aplasia. She underwent a rescue allogeneic stem cell transplant but ultimately succumbed to progressive disease. IEC-HS is an increasingly recognized complication that occurs after CAR-T treatments that can result in aplasia, a dangerous complication with serious sequelae including infection, transfusion dependence, and high risk for hemorrhage. The underlying mechanism is poorly understood, and further studies are needed to understand how to treat it better.

Cytokine-Induced Killer Cells in Combination with Heat Shock Protein 90 Inhibitors Functioning via the Fas/FasL Axis Provides Rationale for a Potential Clinical Benefit in Burkitt's lymphoma

Constant efforts are being made to develop methods for improving cancer immunotherapy, including cytokine-induced killer (CIK) cell therapy. Numerous heat shock protein (HSP) 90 inhibitors have been assessed for antitumor efficacy in preclinical and clinical trials, highlighting their individual prospects for targeted cancer therapy. Therefore, we tested the compatibility of CIK cells with HSP90 inhibitors using Burkitt's lymphoma (BL) cells. Our analysis revealed that CIK cytotoxicity in BL cells was augmented in combination with independent HSP90 inhibitors 17-DMAG (17-dimethylaminoethylamino-17-demethoxygeldanamycin) and ganetespib. Interestingly, CIK cell cytotoxicity did not diminish after blocking with NKG2D (natural killer group 2, member D), which is a prerequisite for their activation. Subsequent analyses revealed that the increased expression of Fas on the surface of BL cells, which induces caspase 3/7-dependent apoptosis, may account for this effect. Thus, we provide evidence that CIK cells, either alone or in combination with HSP90 inhibitors, target BL cells via the Fas-FasL axis rather than the NKG2D pathway. In the context of clinical relevance, we also found that high expression of HSP90 family genes (HSP90AA1, HSP90AB1, and HSP90B1) was significantly associated with the reduced overall survival of BL patients. In addition to HSP90, genes belonging to the Hsp40, Hsp70, and Hsp110 families have also been found to be clinically significant for BL survival. Taken together, the combinatorial therapy of CIK cells with HSP90 inhibitors has the potential to provide clinical benefits to patients with BL.

Blinatumomab in Relapsed/Refractory Burkitt Lymphoma

In patients with relapsed/refractory Burkitt lymphoma (r/r BL), overall survival (OS) is poor, and effective therapies and evidence for the best therapy are lacking. The monoclonal antibody blinatumomab may represent a novel option. However, only limited data on the use of blinatumomab in r/r BL are so far available. This multi-center, retrospective case series investigated nine patients with r/r BL treated with blinatumomab. The safety of blinatumomab was assessed with respect to frequency and severity of adverse effects (AEs) infections, cytokine release syndrome (CRS) and neurotoxicity. Progression-free survival (PFS), OS and overall response rate (ORR) were analyzed to assess efficacy. No AEs > grade 2 occurred, and AEs were generally treatable and fully reversible. The best response to blinatumomab was complete remission in 3/9 patients and partial remission in 2/9, whilst 4/9 presented with progressive disease. Median PFS and OS were 2 and 6 months, respectively, ranging from 5 days to 32 months and 11 days to 32 months, respectively. Blinatumomab treatment was a successful bridging treatment to stem cell transplantation in 3/9 patients. The response to blinatumomab varied widely, and only one patient survived longer term, but activity in patients with r/r BL was evident in some patients, with its use being safe, warranting its prospective investigation.

CD19 chimeric antigen receptor T-cell therapy following autologous stem cell transplantation against relapsed or refractory Burkitt lymphoma/leukemia: A case report and literature review

Burkitt lymphoma or leukemia (BL) is a highly aggressive non-Hodgkin lymphoma. Older age (over 60 years old) and the presence of high-risk factors (such as abdominal mass, high levels of the serum lactic dehydrogenase, Ann Arbor stage II-IV and so on) usually predict a poorer outcome. Chimeric antigen receptor T cells (CART) have achieved remarkable success in the treatment of B-cell leukemia and lymphoma. Here, for the first time, we report a 61-year-old, high-risk BL patient with autologous stem cell transplantation (ASCT) bridging therapy prior to CART as consolidation therapy. Our findings demonstrate that the combination of ASCT and CART for BL is safe and feasible.