Targeted and cellular therapies in lymphoma: Mechanisms of escape and innovative strategies

The Improving Outcomes in Relapsed-Refractory Diffuse Large B Cell Lymphoma: The Role of CAR T-Cell Therapy

OPINION STATEMENT

Diffuse large B cell lymphoma, not otherwise specified (DLBCL-NOS) is the most common aggressive lymphoma and can be cured with CHOP-R immunochemotherapy in 60% of cases. The second-line therapy includes salvage regimens followed by autologous stem cell transplantation (ASCT), which offers a cure to a minority of patients due to limitations in efficacy and eligibility. These data present the unmet need in the field, and this review article focuses on how second-generation chimeric antigen receptor T (CAR T) cell therapy targeting CD19 antigen may improve the outcomes with relapsed/refractory DLBCL. In heavily pretreated patients, who have dismal outcomes with conventional therapy, all three approved products-tisangenlecleucel (tisa-cel), axicabtagene ciloleucel (axi-cel), and lisocabtagene maraleucel (liso-cel) have shown durable, unprecedented complete responses with the potential for cure. When compared to salvage regimens and ASCT as the standard of care, axi-cel and liso-cel, unlike tisa-cel, have demonstrated superiority in long-term control. In ASCT-ineligible r/r DLBCL, liso-cel has shown a favourable benefit-risk ratio. Regarding safety, two adverse events of interest have emerged: cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, both of which are manageable. Real-world evidence reflects the results of pivotal trials while favouring axi-cel in heavily pretreated patients, albeit with higher toxicity. The main barrier to the implementation of this treatment modality is the cost associated with the process of CAR T therapy, along with complications and reimbursement issues. However, the barriers can be overcome, and CAR T therapy has the potential to become the standard of care in relapsed/refractory DLBCL. Furthermore, with advances in the scientific engineering of CAR products and the understanding of novel treatment modalities currently being tested in clinical trials, we believe that targeted cellular therapy will become the future of relapsed/refractory DLBCL treatment.

What We Know and Do Not Yet Know About the Canine Model of Lymphoma in Human Medicine-The Current State of Knowledge

This review comprehensively compares lymphoma in humans and dogs, highlighting the canine model's utility in translational research. Canine lymphoma (cL), predominantly diffuse large B-cell lymphoma (DLBCL), mirrors human non-Hodgkin's lymphoma (NHL) in its clinical presentation, including lymphadenopathy, systemic symptoms (e.g., fever, weight loss), and hematological abnormalities. Morphologically, cL and NHL share similarities in DLBCL subtypes (centroblastic, immunoblastic, anaplastic), although some variations exist, such as the presence of macronuclear medium-sized cells in canine polymorphonuclear centroblastic lymphoma, not observed in humans. Canine and human lymphomas share molecular mechanisms, including the activation of key pathways like NF-κB and mTOR, and genetic and epigenetic alterations. The tumor microenvironment influences tumor growth and immune evasion in both species. Both species exhibit similar responses to chemotherapy, primarily CHOP-based protocols, although canine lymphoma often progresses more rapidly, offering advantages for shorter clinical trials. Molecular targeted therapy is emerging as a promising treatment, with human therapies like rituximab and chimeric antigen receptor T-cell therapy showing efficacy, and canine treatments still developing. Epidemiological data reveal overlapping risk factors, including exposure to environmental carcinogens (e.g., household chemicals, pollution) and the potential influence of sex hormones, although the role of sex hormones requires further investigation in canines. While staging systems differ slightly (Lugano modification of Ann Arbor for humans, WHO system for dogs), both consider disease extent and systemic involvement. Prognostic factors, such as lactate dehydrogenase (LDH) levels, are relevant in human NHL but have not shown consistent utility in cL. This study concludes that the spontaneous development of cL in immunocompetent dogs, coupled with its clinical, histological, and therapeutic similarities to human NHL, makes the canine model invaluable for preclinical research, accelerating the development of novel diagnostic tools and therapies for both human and canine lymphoma. The shared environmental risk factors and shorter disease progression in dogs further enhance the translational potential of this model, promoting a One Health approach to cancer research.

Implication of protein post translational modifications in gastric cancer

Gastric cancer (GC) is one of the most common and highly lethal malignant tumors worldwide, and its occurrence and development are regulated by multiple molecular mechanisms. Post-translational modifications (PTM) common forms include ubiquitylation, phosphorylation, acetylation and methylation. Emerging research has highlighted lactylation and glycosylation. The diverse realm of PTM and PTM crosstalk is linked to many critical signaling events involved in neoplastic transformation, carcinogenesis and metastasis. This review provides a comprehensive overview of the impact of PTM on the occurrence and progression of GC. Specifically, aberrant PTM have been shown to alter the proliferation, migration, and invasion capabilities of GC cells. Moreover, PTM are closely associated with resistance to chemotherapeutic agents in GC. Notably, this review also discusses the phenomenon of PTM crosstalk, highlighting the interactions among PTM and their roles in regulating signaling pathways and protein functions. Therefore, in-depth investigation into the mechanisms of PTM and the development of targeted therapeutic strategies hold promise for advancing early diagnosis, treatment, and prognostic evaluation of GC, offering novel insights and future research directions.

Recent Advances in enhancer of zeste homolog 2 Inhibitors: Structural insights and therapeutic applications

Enhancer of Zeste Homolog 2 (EZH2) is overexpressed in many malignancies and plays a critical role in cancer progression. Therefore, it is considered a promising target for therapeutic intervention. Although several EZH2 inhibitors have entered clinical trials, only one has received FDA approval. In this review, we focus on the latest advancements in highly selective and potent dual-targeting EZH2 inhibitors, as well as proteolysis-targeted chimeras (PROTACs) and hydrophobic tagging (HYT) degraders. These novel compounds have been developed to address the existing gaps in the management of abnormal EZH2 expression. Notably, EZH2 inhibitors have shown great efficacy in antitumor therapy and have also demonstrated promising results in antiviral, anti-inflammatory, antisclerotic, bone protection, and nerve injury pain applications. The insights gained from this analysis could provide valuable guidance for future drug design and optimization of EZH2 inhibitors, potentially expediting the discovery of new inhibitors or degraders targeting EZH2.

Triple targeting of RSK, AKT, and S6K as pivotal downstream effectors of PDPK1 by TAS0612 in B-cell lymphomas

B-cell lymphomas (BCLs) are the most common disease entity among hematological malignancies and have various genetically and molecularly distinct subtypes. In this study, we revealed that the blockade of phosphoinositide-dependent kinase-1 (PDPK1), the master kinase of AGC kinases, induces a growth inhibition via cell cycle arrest and the induction of apoptosis in all eight BCL-derived cell lines examined, including those from activated B-cell-like diffuse large B-cell lymphoma (DLBCL), double expressor DLBCL, Burkitt lymphoma, and follicular lymphoma. We also demonstrated that, in these cell lines, RSK2, AKT, and S6K, but not PLK1, SGK, or PKC, are the major downstream therapeutic target molecules of PDPK1 and that RSK2 plays a central role and AKT and S6K play subsidiary functional roles as the downstream effectors of PDPK1 in cell survival and proliferation. Following these results, we confirmed the antilymphoma efficacy of TAS0612, a triple inhibitor for total RSK, including RSK2, AKT, and S6K, not only in these cell lines, regardless of disease subtypes, but also in all 25 patient-derived B lymphoma cells of various disease subtypes. At the molecular level, TAS0612 caused significant downregulation of MYC and mTOR target genes while inducing the tumor suppressor TP53INP1 protein in these cell lines. These results prove that the simultaneous blockade of RSK2, AKT, and S6K, which are the pivotal downstream substrates of PDPK1, is a novel therapeutic target for the various disease subtypes of BCLs and line up TAS0612 as an attractive candidate agent for BCLs for future clinical development.