Beyond Bruton's tyrosine kinase inhibitors in mantle cell lymphoma: bispecific antibodies, antibody-drug conjugates, CAR T-cells, and novel agents.

Mantle cell lymphoma is a B cell non-Hodgkin lymphoma (NHL), representing 2-6% of all NHLs and characterized by overexpression of cyclin D1. The last decade has seen the development of many novel treatment approaches in MCL, most notably the class of Bruton's tyrosine kinase inhibitors (BTKi). BTKi has shown excellent outcomes for patients with relapsed or refractory MCL and is now being studied in the first-line setting. However, patients eventually progress on BTKi due to the development of resistance. Additionally, there is an alteration in the tumor microenvironment in these patients with varying biological and therapeutic implications. Hence, it is necessary to explore novel therapeutic strategies that can be effective in those who progressed on BTKi or potentially circumvent resistance. In this review, we provide a brief overview of BTKi, then discuss the various mechanisms of BTK resistance including the role of genetic alteration, cancer stem cells, tumor microenvironment, and adaptive reprogramming bypassing the effect of BTK inhibition, and then provide a comprehensive review of current and emerging therapeutic options beyond BTKi including novel agents, CAR T cells, bispecific antibodies, and antibody-drug conjugates.

Efficacy of Ferulic Acid in an Animal Model of Drug-Resistant Epilepsy: Beneficial or Not?

Background Lamotrigine (LTG) and subconvulsive doses of pentylenetetrazol (PTZ) as a model mimic drug-resistant epilepsy (DRE), which is a serious unmet medical condition. Previous evidence suggests an imperative role of neuroinflammation in the development of DRE. Various preclinical models of brain injury have reported potent anti-inflammatory and antioxidant properties of ferulic acid (FA). Therefore, its efficacy against intractable epilepsy is worthwhile to study. Materials and methods The present study evaluated the efficacy of FA in LTG and PTZ-induced refractory seizures in mice. On every alternate day for 38 days, LTG (5mg/kg) was injected before PTZ (30-40mg/kg) to establish a murine model of DRE. Animals were treated with two doses of FA (40, 80 mg/kg). All the animals were assessed for seizure score and the latency of seizures every alternate day till the end of the study. Histopathological score and the levels of pro-inflammatory mediators, interleukin-1ßeta (IL-Iß), tumor necrosis factor-alpha (TNF-α), and matrix metalloproteinase-9 (MMP-9) were quantified in the brain tissue of these mice.  Results Ferulic acid (FA) neither decreases the LTG and PTZ-induced refractory seizures score nor increases the latency to develop seizures. In addition, the injury to hippocampal neurons and the levels of pro-inflammatory cytokines were comparable with two doses of FA in treated mice. Conclusion In the present study, single-dose FA treatment does not show any beneficial effect against the LTG/PTZ model of DRE. Therefore, its single-dose administration might not be beneficial against the DRE model.

Next-Generation Sequencing Highlights of Diffuse Large B-cell Lymphoma in a Tertiary Care Hospital in North India.

INTRODUCTION: Next-generation sequencing (NGS) elucidates the diffuse large B-cell lymphoma (DLBCL) genetic characteristics by finding recurrent and novel somatic mutations. This observational study attempted to create an NGS panel with a focus on identifying novel somatic mutations which could have potential clinical and therapeutic implications. This panel was created to look for mutations in 133 genes chosen on basis of a literature review and it was used to sequence the tumor DNA of 20 DLBCL patients after a centralized histopathologic review. METHODS: The study included 20 patients having DLBCL. The quality and quantity of tumor cells were accessed by H&E staining and correlated with histopathology and Immunohistochemistry (IHC) status. Patients were grouped as ABC (activated B-cell), PMBL (primary mediastinal large B-cell lymphoma), and other or unclassified subtypes. The lymphoma panel of 133 was designed on targeted sequencing of multiple genes for the coding regions through NGS. The libraries were prepared and sequenced using the Illumina platform. The alignment of obtained sequences was performed using Burrows-Wheeler Aligner and identification of somatic mutations was done using LoFreq (version 2) variant caller. The mutations were annotated using an annotation pipeline (VariMAT). Previously published literature and databases were used for the annotation of clinically relevant mutations. The common variants were filtered for reporting based on the presence in various population databases (1000G, ExAC, EVS, 1000Japanese, dbSNP, UK10K, MedVarDb). A custom read-depth-based algorithm was used to determine CNV (Copy Number Variants) from targeted sequencing experiments. Rare CNVs were detected using a comparison of the test data read-depths with the matched reference dataset. Reportable mutations were prioritized and prepared based on AMP-ASCO-CAP (Association for Molecular Pathology-American Society of Clinical Oncology-College of American Pathologists), WHO guidelines, and also based on annotation metrics from OncoMD (a knowledge base of genomic alterations). RESULTS: The informativity of the panel was 95 percent. NOTCH 1 was the most frequently mutated gene in 16.1% of patients followed by 12.9% who had ARID1A mutations. MYD88 and TP53 mutations were detected in 9.6% of the patient while 6.4% of patients had CSF3R mutations. NOTCH 1 and TP 53 are the most frequently reported gene in the middle age group (40-60). Mutation in MYD88 is reported in every age group. MYD88 (51%) is the most common mutation in ABC subtypes of DLBCL, followed by NOTCH 1 (44%) and SOCS 1 (33%) according to our findings. NOTCH 1 mutations are frequent in ABC and PMBL subtypes. Closer investigation reveals missense mutation is the most frequent mutation observed in the total cohort targeting 68.4% followed by frameshift deletion reported in 26.3%. Six novel variants have been discovered in this study. CONCLUSIONS: This study demonstrates the high yield of information in DLBCL using the NGS Lymphoma panel. Results also highlight the molecular heterogeneity of DLBCL subtypes which indicates the need for further studies to make the results of the NGS more clinically relevant.

Ibrutinib Resistance Mechanisms and Treatment Strategies for B-Cell lymphomas.

Chronic activation of B-cell receptor (BCR) signaling via Bruton tyrosine kinase (BTK) is largely considered to be one of the primary mechanisms driving disease progression in B-Cell lymphomas. Although the BTK-targeting agent ibrutinib has shown promising clinical responses, the presence of primary or acquired resistance is common and often leads to dismal clinical outcomes. Resistance to ibrutinib therapy can be mediated through genetic mutations, up-regulation of alternative survival pathways, or other unknown factors that are not targeted by ibrutinib therapy. Understanding the key determinants, including tumor heterogeneity and rewiring of the molecular networks during disease progression and therapy, will assist exploration of alternative therapeutic strategies. Towards the goal of overcoming ibrutinib resistance, multiple alternative therapeutic agents, including second- and third-generation BTK inhibitors and immunomodulatory drugs, have been discovered and tested in both pre-clinical and clinical settings. Although these agents have shown high response rates alone or in combination with ibrutinib in ibrutinib-treated relapsed/refractory(R/R) lymphoma patients, overall clinical outcomes have not been satisfactory due to drug-associated toxicities and incomplete remission. In this review, we discuss the mechanisms of ibrutinib resistance development in B-cell lymphoma including complexities associated with genomic alterations, non-genetic acquired resistance, cancer stem cells, and the tumor microenvironment. Furthermore, we focus our discussion on more comprehensive views of recent developments in therapeutic strategies to overcome ibrutinib resistance, including novel BTK inhibitors, clinical therapeutic agents, proteolysis-targeting chimeras and immunotherapy regimens.