Impact of the clinically approved BTK inhibitors on the conformation of full-length BTK and analysis of the development of BTK resistance mutations in chronic lymphocytic leukemia.

Inhibition of Bruton's tyrosine kinase (BTK) has proven to be highly effective in the treatment of B-cell malignancies such as chronic lymphocytic leukemia (CLL), autoimmune disorders, and multiple sclerosis. Since the approval of the first BTK inhibitor (BTKi), Ibrutinib, several other inhibitors including Acalabrutinib, Zanubrutinib, Tirabrutinib, and Pirtobrutinib have been clinically approved. All are covalent active site inhibitors, with the exception of the reversible active site inhibitor Pirtobrutinib.

A second generation of senotherapies: the development of targeted senolytics, senoblockers and senoreversers for healthy ageing.

Cellular senescence, a form of terminal cell cycle arrest, is as a key driver of organismal ageing and an important factor in age-related diseases. Insights into the senescent phenotype have led to the development of novel therapeutic strategies, collectively known as senotherapies, that aim to ameliorate the detrimental effects of senescent cell accumulation in tissues. The senotherapeutic field has rapidly evolved over the past decade, with clinical translation of the first drugs discovered currently underway.

Examining variability in the diagnosis and management of people with bleeding disorders of unknown cause: communication from the ISTH SSC Subcommittee on von Willebrand Factor.

Background: Bleeding disorder of unknown cause (BDUC) is characterized by a bleeding phenotype in the setting of normal hemostatic testing. No standardized diagnostic criteria or treatment algorithms exist for people with BDUC. To address the unmet need, the International Society on Thrombosis and Haemostasis von Willebrand Factor Scientific Subcommittee performed a real-world survey aimed at addressing knowledge gaps, developing consensus pathways, and ultimately improving care.

Identification of a novel form of caspase-independent cell death triggered by BH3-mimetics in diffuse large B-cell lymphoma cell lines.

BH3-mimetics represent promising anti-cancer agents in tumors that rely on the anti-apoptotic function of B-Cell Lymphoma 2 (BCL2) proteins, particularly in leukemia and lymphoma cells primed for apoptosis. Mechanistically, BH3-mimetics may displace pro-apoptotic binding partners thus inducing BAX/BAK-mediated mitochondrial permeabilization followed by cytochrome c release, activation of the caspase cascade and apoptosis. Here, we describe a novel mode of caspase-independent cell death (CICD) induced by BH3-mimetics in a subset of diffuse large B-cell lymphoma (DLBCL) cells.

Computational modeling of DLBCL predicts response to BH3-mimetics.

In healthy cells, pro- and anti-apoptotic BCL2 family and BH3-only proteins are expressed in a delicate equilibrium. In contrast, this homeostasis is frequently perturbed in cancer cells due to the overexpression of anti-apoptotic BCL2 family proteins. Variability in the expression and sequestration of these proteins in Diffuse Large B cell Lymphoma (DLBCL) likely contributes to variability in response to BH3-mimetics.

Characterization of the HDAC/PI3K inhibitor CUDC-907 as a novel senolytic.

The accumulation of senescent cells has an important role in the phenotypical changes observed in ageing and in many age-related pathologies. Thus, the strategies designed to prevent these effects, collectively known as senotherapies, have a strong clinical potential. Senolytics are a type of senotherapy aimed at specifically eliminating senescent cells from tissues.

poly(I:C) synergizes with proteasome inhibitors to induce apoptosis in cervical cancer cells.

Cervical cancer is one of the most common malignancies in women, with a poor survival rate. Thus, there is a need to define effective combination strategies to improve therapy. In this study, we report that dsRNA poly(I:C) up-regulated the expression of IFNβ and apoptosis-associated genes in cervical cancer cells, activating both intrinsic and extrinsic apoptotic pathways, and eventually inducing cell death.

Targeted clearance of senescent cells using an antibody-drug conjugate against a specific membrane marker.

A wide range of diseases have been shown to be influenced by the accumulation of senescent cells, from fibrosis to diabetes, cancer, Alzheimer's and other age-related pathologies. Consistent with this, clearance of senescent cells can prolong healthspan and lifespan in in vivo models. This provided a rationale for developing a new class of drugs, called senolytics, designed to selectively eliminate senescent cells in human tissues.

Mantle cell lymphomas with concomitant MYC and CCND1 breakpoints are recurrently TdT positive and frequently show high-grade pathological and genetic features.

Chromosomal breakpoints involving the MYC gene locus, frequently referred to as MYC rearrangements (MYC - R+), are a diagnostic hallmark of Burkitt lymphoma and recurrent in many other subtypes of B-cell lymphomas including follicular lymphoma, diffuse large B-cell lymphoma and other high-grade B-cell lymphomas and are associated with an aggressive clinical course. In remarkable contrast, in MCL, only few MYC - R+ cases have yet been described. In the current study, we have retrospectively analysed 16 samples (MYC - R+, n = 15, MYC - R-, n = 1) from 13 patients and describe their morphological, immunophenotypic and (molecular) genetic features and clonal evolution patterns.

Genome-wide association study identifies risk loci for progressive chronic lymphocytic leukemia.

Prognostication in patients with chronic lymphocytic leukemia (CLL) is challenging due to heterogeneity in clinical course. We hypothesize that constitutional genetic variation affects disease progression and could aid prognostication. Pooling data from seven studies incorporating 842 cases identifies two genomic locations associated with time from diagnosis to treatment, including 10q26.

Genetic evidence for partial redundancy between the arginine methyltransferases CARM1 and PRMT6.

CARM1 is a protein arginine methyltransferase (PRMT) that acts as a coactivator in a number of transcriptional programs. CARM1 orchestrates this coactivator activity in part by depositing the H3R17me2a histone mark in the vicinity of gene promoters that it regulates. However, the gross levels of H3R17me2a in CARM1 KO mice did not significantly decrease, indicating that other PRMT(s) may compensate for this loss.

Phase Ib Study of Tirabrutinib in Combination with Idelalisib or Entospletinib in Previously Treated Chronic Lymphocytic Leukemia.

Purpose: Bruton tyrosine kinase (BTK) inhibition alone leads to incomplete responses in chronic lymphocytic leukemia (CLL). Combination therapy may reduce activation of escape pathways and deepen responses. This open-label, phase Ib, sequential dose-escalation and dose-expansion study evaluated the safety, tolerability, pharmacokinetics, and preliminary efficacy of the selective BTK inhibitor tirabrutinib alone, in combination with the PI3K delta (PI3Kδ) inhibitor idelalisib, or with the spleen tyrosine kinase (SYK) inhibitor entospletinib in patients with relapsed/refractory CLL.

Dual dependence on BCL2 and MCL1 in T-cell prolymphocytic leukemia.

Treatment of relapsed refractory T-PLL with venetoclax monotherapy results in only transient and minor clinical responses. In vitro analyses pre- and postvenetoclax indicate dual dependence on BCL2 and MCL1; combined BCL2 and MCL1 inhibition are synergistic.