pci-32765 and Disease-Models--Animal

Most patients with indolent B-cell lymphomas fail to achieve complete remission with current treatment approaches and invariably relapse. During the past decade, innovative immunochemotherapy strategies have substantially improved disease control rates but not survival, thus providing the rationale for development of novel agents targeting dysregulated pathways that are operable in these hematological malignancies. Ibrutinib, a novel first-in-human Bruton's tyrosine kinase (BTK) inhibitor, has progressed into phase III trials after early-phase clinical studies demonstrated effective target inhibition, increased tumor response rates, and significant improvement in survival, particularly in patients with indolent B-cell lymphomas. Recently, the compound was designated a "breakthrough therapy" by the United States Food and Drug Administration for the treatment of patients with relapsed or refractory mantle cell lymphoma and Waldenström macroglobulinemia. This review summarizes recent achievements of ibrutinib, with a focus on its emerging role in the treatment of patients with indolent B-cell lymphoid malignancies.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Antineoplastic Agents; Clinical Trials as Topic; Disease Models, Animal; Drug Evaluation, Preclinical; Humans; Lymphoma, B-Cell; Piperidines; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Signal Transduction

Chronic lymphocytic leukemia (CLL) cells depend on microenvironmental interactions for proliferation and survival that are at least partially mediated through B-cell receptor (BCR) signaling. Ibrutinib, a Bruton tyrosine kinase inhibitor, disrupts BCR signaling and leads to the egress of tumor cells from the microenvironment. Although the on-target effects on CLL cells are well defined, the impact on the microenvironment is less well studied. We therefore sought to characterize the in vivo effects of ibrutinib on the tumor microenvironment.. Patients received single-agent ibrutinib on an investigator-initiated phase II trial. Serial blood and tissue samples were collected pretreatment and during treatment. Changes in cytokine levels, cellular subsets, and microenvironmental interactions were assessed.. Serum levels of key chemokines and inflammatory cytokines decreased significantly in patients on ibrutinib. Furthermore, ibrutinib treatment decreased circulating tumor cells and overall T-cell numbers. Most notably, a reduced frequency of the Th17 subset of CD4(+)T cells was observed concurrent with reduced expression of activation markers and PD-1 on T cells. Consistent with direct inhibition of T cells, ibrutinib inhibited Th17 differentiation of murine CD4(+)T cells in vitro Finally, in the bone marrow microenvironment, we found that ibrutinib disaggregated the interactions of macrophages and CLL cells, inhibited secretion of CXCL13, and decreased the chemoattraction of CLL cells.. In conjunction with inhibition of BCR signaling, these changes in the tumor microenvironment likely contribute to the antitumor activity of ibrutinib and may impact the efficacy of immunotherapeutic strategies in patients with CLL. See related commentary by Bachireddy and Wu, p. 1547.

Topics: Adenine; Aged; Aged, 80 and over; Animals; Antineoplastic Agents; Bone Marrow; Cell Communication; Cell Differentiation; Cell Movement; Cytokines; Disease Models, Animal; Female; Humans; Immunophenotyping; Inflammation Mediators; Leukemia, Lymphocytic, Chronic, B-Cell; Macrophages; Male; Mice; Middle Aged; Piperidines; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; T-Lymphocyte Subsets; Th17 Cells; Tumor Microenvironment

Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy is highly promising but requires robust T-cell expansion and engraftment. A T-cell defect in chronic lymphocytic leukemia (CLL) due to disease and/or therapy impairs ex vivo expansion and response to CAR T cells. To evaluate the effect of ibrutinib treatment on the T-cell compartment in CLL as it relates to CAR T-cell generation, we examined the phenotype and function of T cells in a cohort of CLL patients during their course of treatment with ibrutinib. We found that ≥5 cycles of ibrutinib therapy improved the expansion of CD19-directed CAR T cells (CTL019), in association with decreased expression of the immunosuppressive molecule programmed cell death 1 on T cells and of CD200 on B-CLL cells. In support of these findings, we observed that 3 CLL patients who had been treated with ibrutinib for ≥1 year at the time of T-cell collection had improved ex vivo and in vivo CTL019 expansion, which correlated positively together and with clinical response. Lastly, we show that ibrutinib exposure does not impair CAR T-cell function in vitro but does improve CAR T-cell engraftment, tumor clearance, and survival in human xenograft models of resistant acute lymphocytic leukemia and CLL when administered concurrently. Our collective findings indicate that ibrutinib enhances CAR T-cell function and suggest that clinical trials with combination therapy are warranted. Our studies demonstrate that improved T-cell function may also contribute to the efficacy of ibrutinib in CLL. These trials were registered at www.clinicaltrials.gov as #NCT01747486, #NCT01105247, and #NCT01217749.

Topics: Adenine; Administration, Oral; Aged; Animals; Antigens, CD; Cell Line, Tumor; Cell Proliferation; Cytotoxicity, Immunologic; Demography; Disease Models, Animal; Drug Resistance, Neoplasm; Gene Transfer Techniques; Humans; Immunosuppression Therapy; K562 Cells; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Mice; Middle Aged; Piperidines; Programmed Cell Death 1 Receptor; Pyrazoles; Pyrimidines; Receptors, Antigen, T-Cell; T-Lymphocytes; Time Factors; Treatment Outcome

Given its critical role in T-cell signaling, interleukin-2-inducible kinase (ITK) is an appealing therapeutic target that can contribute to the pathogenesis of certain infectious, autoimmune, and neoplastic diseases. Ablation of ITK subverts Th2 immunity, thereby potentiating Th1-based immune responses. While small-molecule ITK inhibitors have been identified, none have demonstrated clinical utility. Ibrutinib is a confirmed irreversible inhibitor of Bruton tyrosine kinase (BTK) with outstanding clinical activity and tolerability in B-cell malignancies. Significant homology between BTK and ITK alongside in silico docking studies support ibrutinib as an immunomodulatory inhibitor of both ITK and BTK. Our comprehensive molecular and phenotypic analysis confirms ITK as an irreversible T-cell target of ibrutinib. Using ibrutinib clinical trial samples along with well-characterized neoplastic (chronic lymphocytic leukemia), parasitic infection (Leishmania major), and infectious disease (Listeria monocytogenes) models, we establish ibrutinib as a clinically relevant and physiologically potent ITK inhibitor with broad therapeutic utility. This trial was registered at www.clinicaltrials.gov as #NCT01105247 and #NCT01217749.

Topics: Adenine; Animals; CD8-Positive T-Lymphocytes; Disease Models, Animal; Enzyme Inhibitors; Humans; Jurkat Cells; Leishmaniasis, Cutaneous; Leukemia; Listeriosis; Lymphocyte Activation; Mice; Piperidines; Primary Cell Culture; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Th1 Cells; Th2 Cells

Th2 and Th17 immune response contribute to allergic rhinitis (AR) development. Targeting Th2 and Th17 response has been shown to ameliorate AR. Ibrutinib is an inhibitor for IL2-inducible T-cell kinase, which can promote Th2 and Th17 immune response. We sought to investigate the effect of ibrutinib on AR and the underlying mechanisms. We established house dust mite-induced AR mouse model and treated AR mice with ibrutinib. The symptoms of AR, serum level of immunoglobulin E, percentage of Th1, Th2, Th17, and Treg in nasal lymphoid tissues were monitored. We also established in vitro T cell differentiation cell culture model. The T cells were treated with ibrutinib and the expression of specific transcriptional factors and cytokines was measured. The activation of PLC-γ1/calcium/NFAT2 signaling pathway was detected. Ibrutinib treatment had no effects on the development of lymphocytes and myeloid cells, but alleviated AR symptoms and decreased Th2 cell population in nasal lymphoid tissue. Meanwhile, iburitnib suppressed Th2 and Th17 differentiation in vitro. Moreover, iburitnib prevented phosphorylation of PLC-γ1and nuclear translocation of NFAT2 in Th2 cells. Our results suggested that ibrutinib could ameliorate AR symptoms through suppression of Th2 differentiation in AR mouse model.

Topics: Adenine; Animals; Cell Differentiation; Cytokines; Disease Models, Animal; Mice; Mice, Inbred BALB C; Nasal Mucosa; Piperidines; Protein-Tyrosine Kinases; Rhinitis; Rhinitis, Allergic; Th2 Cells

Acute lung injury is a severe complication of sepsis with high mortality in ICU. Increasing evidences have showed that Ibrutinib, a Bruton's Tyrosine kinase inhibitor, plays a critical role in numerous inflammation-related diseases. However, its therapeutic effect and mechanism in sepsis induced acute lung injury remain unclear. In this study, cecal ligation puncture (CLP) was performed on male C57BL/6 J mice to establish a mouse model of sepsis. Ibrutinib (50 mg/kg/d) was administered by gavage 1 day before CLP, once a day, for 3 consecutive days. on the fourth day mice were given one dose of ibrutinib 2 h before CLP induction, and another dose was given 24 h later. Histopathological examination of lung tissues was performed at 72 h. The levels of myeloperoxidase (MPO), interleukin (IL)- 6, TNF-α, IL-1β and IL-18 in bronchoalveolar lavage fluid (BALF) were determined by ELISA. Western blotting was used to detect the expression of pyroptosis related proteins. The results showed that Ibrutinib treatment significantly improved the prognosis of mice and mitigated the lung histopathological injury and inflammatory response. Moreover, Ibrutinib significantly inhibited the expression of pyroptosis related proteins (NLRP3, Caspase-1, Gasdermin D (GSDMD), IL-1β and IL-18) in the lung tissues of sepsis mice. In conclusion, our results suggest that Ibrutinib exerted protective effects against lung injury of septic mice and inhibited the activation of pyroptosis in lung tissue, which may be a potential treatment for sepsis induced lung injury.

Topics: Acute Lung Injury; Animals; Caspase 1; Disease Models, Animal; Interleukin-18; Interleukin-6; Male; Mice; Mice, Inbred C57BL; NLR Family, Pyrin Domain-Containing 3 Protein; Sepsis

The covalent inhibitor of Bruton's tyrosine kinase ibrutinib and the specific Bcl-2 inhibitor venetoclax are both highly efficacious single-agent drugs in the treatment of chronic lymphocytic leukemia (CLL). Based on their complementary modes of action, ibrutinib and venetoclax are hypothesized to act in a synergistic fashion. Currently, it is unclear whether combined treatment is indeed superior to continuous single-agent treatment and what mechanisms underlie the resistance to combination treatment. In addition, the effects of such treatment on the skewed T-cell compartment characteristic of CLL are as yet unknown. In the murine Eµ-TCL1 adoptive transfer model resembling aggressive CLL, we found that combined treatment resulted in the deepest responses, with the longest duration related to a combination of decreased proliferation and increased induction of apoptosis. In addition, alterations in T-cell subsets were most prominent after combination treatment, with increased naive cells and reduced effector memory cells. Remarkably, effects of single agents but also combination treatment were eventually interrupted by relapse, and we found downregulation of BIM expression as a plausible cause of acquired drug resistance. Nevertheless, in this murine model, the combination of venetoclax and ibrutinib has increased efficacy over single agents, accompanied by a restoration of the T-cell compartment.

Topics: Adenine; Animals; Bridged Bicyclo Compounds, Heterocyclic; Disease Models, Animal; Leukemia, Lymphocytic, Chronic, B-Cell; Mice; Piperidines; Proto-Oncogene Proteins; Pyrazoles; Pyrimidines; Sulfonamides

Current therapies targeting several neurotransmitter systems are only able to partially mitigate the symptoms of stress- and trauma-related disorder. Stress and trauma-related disorders lead to a prominent inflammatory response in humans, and in pre-clinical models. However, mechanisms underlying the induction of neuroinflammatory response in PTSD and anxiety disorders are not clearly understood. The present study investigated the mechanism underlying the activation of proinflammatory NLRP3 inflammasome and IL1β in mouse models of stress.. We used two mouse models of stress, i.e., mice subjected to physical restraint stress with brief underwater submersion, and predator odor stress. Mice were injected with MCC950, a small molecule specific inhibitor of NLRP3 activation. To pharmacologically inhibit BTK, a specific inhibitor ibrutinib was used. To validate the observation from ibrutinib studies, a separate group of mice was injected with another BTK-specific inhibitor LFM-A13. Seven days after the induction of stress, mice were examined for anxious behavior using open field test (OFT), light-dark test (LDT), and elevated plus maze test (EPM). Following the behavior tests, hippocampus and amygdale were extracted and analyzed for various components of NLRP3-caspase 1-IL1β pathway. Plasma and peripheral blood mononuclear cells were also used to assess the induction of NLRP3-Caspase 1-IL-1β pathway in stressed mice.. Using two different pre-clinical models of stress, we demonstrate heightened anxious behavior in female mice as compared to their male counterparts. Stressed animals exhibited upregulation of proinflammatory IL1β, IL-6, Caspase 1 activity and NLRP3 inflammasome activation in brain, which were significantly higher in female mice. Pharmacological inhibition of NLRP3 inflammasome activation led to anxiolysis as well as attenuated neuroinflammatory response. Further, we observed induction of activated Bruton's tyrosine kinase (BTK), an upstream positive-regulator of NLRP3 inflammasome activation, in hippocampus and amygdala of stressed mice. Next, we conducted proof-of-concept pharmacological BTK inhibitor studies with ibrutinib and LFM-A13. In both sets of experiments, we found BTK inhibition led to anxiolysis and attenuated neuroinflammation, as indicated by significant reduction of NLRP3 inflammasome and proinflammatory IL-1β in hippocampus and amygdala. Analysis of plasma and peripheral blood mononuclear cells indicated peripheral induction of NLRP3-caspase 1-IL1β pathway in stressed mice.. Our study identified BTK as a key upstream regulator of neuroinflammation, which drives anxiogenic behavior in mouse model of stress. Further, we demonstrated the sexually divergent activation of BTK, providing a clue to heightened neuroinflammation and anxiogenic response to stress in females as compared to their male counterparts. Our data from the pharmacological inhibition studies suggest BTK as a novel target for the development of potential clinical treatment of PTSD and anxiety disorders. Induction of pBTK and NLRP3 in peripheral blood mononuclear cells of stressed mice suggest the potential effect of stress on systemic inflammation.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Amides; Animals; Anxiety; Disease Models, Animal; Female; Inflammation Mediators; Male; Mice; Mice, Inbred C57BL; Nitriles; NLR Family, Pyrin Domain-Containing 3 Protein; Odorants; Piperidines; Rats; Restraint, Physical; Stress, Psychological

Sepsis is a life-threatening condition which affects multiple organs including the kidney. Sepsis-induced acute kidney injury (AKI) is a major health burden throughout the globe. Pathogenesis of sepsis-induced AKI is complex; however, it involves both innate and adaptive immune cells such as B cells, T cells, dendritic cells (DCs), macrophages, and neutrophils. Bruton's tyrosine kinase (BTK) is reportedly involved in inflammatory and oxidative signaling in different immune cells, however its contribution with respect to sepsis-induced AKI has not been delineated. This study attempted to investigate the role of BTK and its inhibition on oxidizing enzymes NADPH oxidase (NOX-2) and inducible nitric oxide synthase (iNOS) in DCs, neutrophils, and B cells during AKI. Our data reveal that BTK is activated in DCs, neutrophils, and B cells which causes an increase in AKI associated biochemical markers such as serum creatinine/blood urea nitrogen, renal myeloperoxidase activity, and histopathological disturbances in renal tubular structures. Activation of BTK causes upregulation of NOX-2/iNOS/nitrotyrosine in these immune cells and kidney. Treatment with BTK inhibitor, Ibrutinib causes attenuation in AKI associated dysfunction in biochemical parameters (serum creatinine/blood urea nitrogen, renal myeloperoxidase activity) and oxidative stress in immune cells and kidney (iNOS/NOX2/lipid peroxides/nitrotyrosine/protein carbonyls). In summary, the current investigation reveals a compelling role of BTK signaling in sepsis-induced AKI which is evident from amelioration of AKI associated renal dysfunction after its inhibition.

Topics: Acute Kidney Injury; Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; B-Lymphocytes; Dendritic Cells; Disease Models, Animal; Enzyme Inhibitors; Kidney; Male; Mice, Inbred BALB C; NADPH Oxidase 2; Neutrophils; Nitric Oxide Synthase Type II; Oxidative Stress; Piperidines; Sepsis; Signal Transduction

We previously demonstrated that ibrutinib modulates LPS-induced neuroinflammation in vitro and in vivo, but its effects on the pathology of Alzheimer's disease (AD) and cognitive function have not been investigated. Here, we investigated the effects of ibrutinib in two mouse models of AD. In 5xFAD mice, ibrutinib injection significantly reduced Aβ plaque levels by promoting the non-amyloidogenic pathway of APP cleavage, decreased Aβ-induced neuroinflammatory responses, and significantly downregulated phosphorylation of tau by reducing levels of phosphorylated cyclin-dependent kinase-5 (p-CDK5). Importantly, tau-mediated neuroinflammation and tau phosphorylation were also alleviated by ibrutinib injection in PS19 mice. In 5xFAD mice, ibrutinib improved long-term memory and dendritic spine number, whereas in PS19 mice, ibrutinib did not alter short- and long-term memory but promoted dendritic spinogenesis. Interestingly, the induction of dendritic spinogenesis by ibrutinib was dependent on the phosphorylation of phosphoinositide 3-kinase (PI3K). Overall, our results suggest that ibrutinib modulates AD-associated pathology and cognitive function and may be a potential therapy for AD.

Topics: Adenine; Alzheimer Disease; Amyloid beta-Peptides; Animals; Brain; Cognition; Cyclin-Dependent Kinase 5; Cytokines; Dendritic Spines; Disease Models, Animal; Down-Regulation; Gliosis; Inflammation; Inflammation Mediators; Memory, Long-Term; Mice, Transgenic; Neurogenesis; Neuroglia; Phosphorylation; Piperidines; Plaque, Amyloid; tau Proteins

The nucleotide-binding domain leucine-rich repeat containing protein 3 (NLRP3) inflammasome is a critical inflammatory mechanism identified in platelets, which controls platelet activation and aggregation. We have recently shown that the platelet NLRP3 inflammasome is upregulated in sickle cell disease (SCD), which is mediated by Bruton tyrosine kinase (BTK). Here, we investigated the effect of pharmacological inhibition of NLRP3 and BTK on platelet aggregation and the formation of in vitro thrombi in Townes SCD mice. Mice were injected for 4 weeks with the NLRP3 inhibitor MCC950, the BTK inhibitor ibrutinib or vehicle control. NLRP3 activity, as monitored by caspase-1 activation, was upregulated in platelets from SCD mice, which was dependent on BTK. Large areas of platelet aggregates detected in the liver of SCD mice were decreased when mice were treated with MCC950 or ibrutinib. Moreover, platelet aggregation and in vitro thrombus formation were upregulated in SCD mice and were inhibited when mice were subjected to pharmacological inhibition of NLRP3 and BTK. Targeting the NLRP3 inflammasome might be a novel approach for antiplatelet therapy in SCD.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Anemia, Sickle Cell; Animals; Blood Platelets; Disease Models, Animal; Female; Furans; Heterocyclic Compounds, 4 or More Rings; Indenes; Inflammasomes; Liver; Male; Mice, Transgenic; NLR Family, Pyrin Domain-Containing 3 Protein; Piperidines; Platelet Aggregation; Protein Kinase Inhibitors; Sulfonamides; Sulfones; Thrombosis

Idiopathic pulmonary fibrosis (IPF) is a serious and fatal lung disease, with a median survival of only 3-5 years from diagnosis. Janus kinase 3 (JAK3) has a well-established role in the pathogenesis of various autoimmune diseases, including rheumatoid arthritis (RA) and autoimmune-related pulmonary fibrosis. In this study, through the use of a conformationally-constrained design strategy, a series of thieno[3,2-d]pyrimidines were synthesized as potent JAK3 inhibitors for the treatment of IPF. Among them, the most potent JAK3 inhibitor, namely 8e (IC

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Disease Models, Animal; Dose-Response Relationship, Drug; Epithelial Cells; Female; Humans; Idiopathic Pulmonary Fibrosis; Janus Kinase 3; Mice; Mice, Inbred C57BL; Molecular Docking Simulation; Molecular Structure; Protein Kinase Inhibitors; Pyrimidines; Structure-Activity Relationship

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Chimeric antigen receptor (CAR) T-cell therapy is a promising treatment for patients with CD19 B-cell malignancies. Combination strategies that improve CAR T-cell potency, limit tumor environment-mediated immune dysfunction, and directly reduce tumor burden may increase the potential for durable clinical benefit of CAR T-cell therapy. Lisocabtagene maraleucel (liso-cel) is a product therapy candidate being tested in patients with relapsed/refractory non-Hodgkin lymphoma or chronic lymphocytic leukemia. This study assessed the in vitro and in vivo functionality of CAR T cells transduced to express the anti-CD19 CAR of liso-cel in combination with ibrutinib or acalabrutinib. In prolonged stimulation assays, the presence of ibrutinib or acalabrutinib improved the CAR T-cell effector function. RNA-Seq analysis and surface marker profiling of these CAR T cells treated with ibrutinib but not acalabrutinib revealed gene expression changes consistent with skewing toward a memory-like, type 1 T-helper, Bruton tyrosine kinase phenotype. Ibrutinib or acalabrutinib improved CD19 tumor clearance and prolonged survival of tumor-bearing mice when used in combination with CAR T cells. A combination of the defined cell product therapy candidate, liso-cel, with ibrutinib or acalabrutinib is an attractive approach that may potentiate the promising clinical responses already achieved in CD19 B-cell malignancies with each of these single agents.

Topics: Adenine; Animals; Antigens, CD19; Antineoplastic Combined Chemotherapy Protocols; Benzamides; Biomarkers; Combined Modality Therapy; Cytokines; Cytotoxicity, Immunologic; Disease Models, Animal; Humans; Immunotherapy, Adoptive; Lymphocyte Activation; Mice; Neoplasms; Piperidines; Pyrazines; Receptors, Antigen, T-Cell; Receptors, Chimeric Antigen; T-Lymphocytes; Treatment Outcome; Xenograft Model Antitumor Assays

Psoriasis is an unchecked chronic inflammation characterized by thick, erythematous, and scaly plaques on the skin. The role of innate immune cells in the pathogenesis of psoriasis is well documented. Bruton's tyrosine kinase (BTK) has been reported to execute important signaling functions in innate immune cells such as dendritic cells (DCs) and gamma delta T cells. However, whether inhibition of BTK would lead to modulation of innate immune function in the context of psoriatic inflammation remains largely unexplored. In the present study, we investigated the effect of selective BTK inhibitor, PCI-32765 on inflammatory signaling in CD11c + DCs and gamma delta T cells in imiquimod (IMQ)-induced mouse model of psoriasis-like inflammation. Our results show that IMQ treatment led to induction of p-BTK expression along with concomitant increase in inflammatory cytokines (IL-23, TNF-α) in CD11c + DCs in the skin. Preventive treatment with BTK inhibitor led to significant reversal in IMQ-induced inflammatory changes in CD11c + DCs of skin. Further, there was a significant decrease in dermal IL-17A levels and IL-17A + γδ + T cells after treatment with BTK inhibitor. Furthermore, short treatment of back skin with IMQ led to upregulated expression of p-BTK along with inflammatory cytokines in CD11c + DCs (IL-23, TNF-α) and IL-17A in γδ + T cells which were reversed by BTK inhibitor. Overall, our study proposes that BTK signaling serves a crucial signaling function in innate immune cells in the context of psoriatic inflammation in mice. Therefore, BTK might be a promising therapeutic target to treat psoriatic inflammation.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Dendritic Cells; Disease Models, Animal; Humans; Imiquimod; Immunity, Innate; Interleukin-17; Interleukin-23; Intraepithelial Lymphocytes; Male; Mice; Piperidines; Protein Kinase Inhibitors; Psoriasis; Pyrazoles; Pyrimidines; Signal Transduction; Skin

Atrial fibrillation (AF) occurs in up to 11% of cancer patients treated with ibrutinib. The pathophysiology of ibrutinib promoted AF is complicated, as there are multiple interactions involved; the detailed molecular mechanisms underlying this are still unclear. Here, we aimed to determine the electrophysiological and molecular mechanisms of burst-pacing-induced AF in ibrutinib-treated mice. The results indicated differentially expressed proteins in ibrutinib-treated mice, identified through proteomic analysis, were found to play a role in oxidative stress-related pathways. Finally, treatment with an inhibitor of NADPH oxidase (NOX) prevented and reversed AF development in ibrutinib-treated mice. It was showed that the related protein expression of reactive oxygen species (ROS) in the ibrutinib group was significantly increased, including NOX2, NOX4, p22-phox, XO and TGF-β protein expression. It was interesting that ibrutinib group also significantly increased the expression of ox-CaMKII, p-CaMKII (Thr-286) and p-RyR2 (Ser2814), causing enhanced abnormal sarcoplasmic reticulum (SR) Ca

Topics: Acetophenones; Adenine; Animals; Atrial Fibrillation; Calcium; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Disease Models, Animal; Humans; Male; Mice; Myocytes, Cardiac; Piperidines; Protein Interaction Maps; Proteomics; Reactive Oxygen Species; Sarcoplasmic Reticulum; Signal Transduction

Ibrutinib might improve the efficacy of anti-CD19 chimeric antigen receptor (CD19 CAR) T-cell therapy in chronic lymphocytic leukemia (CLL). We studied the possibility and mechanism of the synergistic effect of ibrutinib and CAR-T cells in other types of lymphoma. In this study, we selected the CD19 CAR-T cells of a patient with lymphoma who failed in his CD19 CAR-T-cell therapy and a dose of 8 mg/kg/d ibrutinib. Subcutaneous and tail vein tumorigenic mice were established with Raji cells. The differences in the synergistic effect between these 2 models were compared by bioluminescence imaging (BLI) monitoring and flow cytometry (FCM). The expression of the STAT-3 signaling pathway was assessed by western blot analysis. There was no synergistic effect of ibrutinib and CD19 CAR-T cells in vitro. Programmed cell death-ligand 1 (PD-L1) was expressed in 0.23 ± 0.06% of Raji cells. In the subcutaneous tumorigenic model, the luciferase signal was reduced significantly in the group receiving ibrutinib combined with CD19 CAR-T cells. Moreover, the proportion of CD19 CAR-T cells was higher in the polytherapy group than in the CAR-T-cell monotherapy group. However, we did not get an analogous synergistic effect in the tail vein tumorigenic model. STAT-3 signaling pathway expression in the residual tumor cells did not differ between those with and those without ibrutinib, suggesting that the IL-10/STAT-3/PD-L1 pathway was not involved in the synergistic effect. Therefore, some other mechanism might be a target for ibrutinib. Our results provide evidence for the use of ibrutinib in polytherapy for other types of B-cell lymphoma.

Topics: Adenine; Adult; Aged; Animals; Antigens, CD19; Biomarkers, Tumor; Cell Line, Tumor; Combined Modality Therapy; Disease Models, Animal; Female; Humans; Immunophenotyping; Immunotherapy, Adoptive; Lymphoma, Large B-Cell, Diffuse; Male; Mice; Middle Aged; Neoplasm Staging; Piperidines; Protein Kinase Inhibitors; Receptors, Antigen, T-Cell; STAT3 Transcription Factor; T-Lymphocytes; Treatment Outcome; Xenograft Model Antitumor Assays

We previously reported the Bruton's tyrosine kinase (BTK) inhibitors ibrutinib and acalabrutinib improve outcomes in a mouse model of polymicrobial sepsis. Now we show that genetic deficiency of the BTK gene

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Benzamides; Disease Models, Animal; Inflammasomes; Macrophages; Male; Mice; Mice, Inbred CBA; Multiple Organ Failure; Phagocytosis; Piperidines; Protein Kinase Inhibitors; Pyrazines; Sepsis; X-Linked Combined Immunodeficiency Diseases

Sepsis is one of the most prevalent diseases in the world. The development of cardiac dysfunction in sepsis results in an increase of mortality. It is known that Bruton's tyrosine kinase (BTK) plays a role in toll-like receptor signaling and NLRP3 inflammasome activation, two key components in the pathophysiology of sepsis and sepsis-associated cardiac dysfunction. In this study we investigated whether pharmacological inhibition of BTK (ibrutinib 30 mg/kg and acalabrutinib 3 mg/kg) attenuates sepsis associated cardiac dysfunction in mice. 10-week old male C57BL/6 mice underwent CLP or sham surgery. One hour after surgery mice received either vehicle (5% DMSO + 30% cyclodextrin i.v.), ibrutinib (30 mg/kg i.v.), or acalabrutinib (3 mg/kg i.v.). Mice also received antibiotics and an analgesic at 6 and 18 h. After 24 h, cardiac function was assessed by echocardiography

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Benzamides; Cecum; Disease Models, Animal; Heart; Heart Diseases; Inflammasomes; Ligation; Male; Mice; Mice, Inbred C57BL; Piperidines; Protein Kinase Inhibitors; Punctures; Pyrazines; Pyrazoles; Pyrimidines; Sepsis

BACKGROUND Diabetes causes damage to the soft tissue and bone structure of the foot, referred to as "diabetic foot". Ibrutinib is a Bruton tyrosine kinase (Btk) inhibitor, and the role and mechanism of ibrutinib on the diabetic foot have not been elucidated. MATERIAL AND METHODS Male Wister rats were randomly divided into 3 groups: control group, model group, and ibrutinib group. After 14 days, the ulcer wound size of each group was measured, and the ulcer healing rate was calculated. The level of inflammatory factors interleukin (IL)-1ß, tumor necrosis factor (TNF)-alpha, and IL-6 was detected by enzyme-linked immunosorbent assay (ELISA). Real-time polymerase chain reaction (PCR) was used to analyze the changes of Toll-like receptor 2 (TLR2) and TLR4. The expression of vascular endothelial growth factor (VEGF) and the RAGE (receptor for advanced glycation end product/NF-kappaB (nuclear factor-kappa B) pathway was detected by western blot. RESULTS Blood glucose, blood lipids, serum creatinine, and urea nitrogen (BUN) levels were increased in the model group, together with increased levels of IL-1ß, TNF-alpha, IL-6, as well as TLR2 and TLR4 expression, and there were significant differences compared with the control group (P<0.05). Meanwhile, the model group showed decreased VEGF expression and increased expression of RAGE and NF-kappaB. However, ibrutinib reduced blood sugar, blood lipids, creatinine, and urea nitrogen levels, inhibited the secretion of inflammatory factors, promoted ulcer healing, improved ulcer healing rate, decreased the expression of TLR2, TLR4, RAGE, and NF-kappaB, and increased VEGF expression; there were significant differences in the ibrutinib group compared with the model group (P<0.05). CONCLUSIONS The Btk inhibitor ibrutinib can upregulate VEGF expression, inhibit the expression of TLRs, inhibit the secretion of inflammatory factors, and promote the healing of diabetic foot ulcer possibly by regulating the RAGE/NF-kappaB pathway.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Cytokines; Diabetes Mellitus; Diabetic Foot; Disease Models, Animal; Male; NF-kappa B; Piperidines; Pyrazoles; Pyrimidines; Rats; Rats, Wistar; Receptor for Advanced Glycation End Products; Signal Transduction; Toll-Like Receptors; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A

New drugs are needed for leishmaniasis because current treatments such as pentavalent antimonials are toxic and require prolonged administration, leading to poor patient compliance. Ibrutinib is an anticancer drug known to modulate T-helper type 1 (Th1)/Th2 responses and has the potential to regulate immunity against infectious disease.. In this study, we evaluated the efficacy of oral ibrutinib as a host-targeted treatment for visceral leishmaniasis (VL) caused by Leishmania donovani using an experimental mouse model.. We found that oral ibrutinib was significantly more effective than the pentavalent antimonial sodium stibogluconate (70 mg/kg) for the treatment of VL caused by L. donovani. Ibrutinib treatment increased the number of interleukin 4- and interferon γ-producing natural killer T cells in the liver and spleen and enhanced granuloma formation in the liver. Further, ibrutinib treatment reduced the influx of Ly6Chi inflammatory monocytes, which mediate susceptibility to L. donovani. Finally, ibrutinib treatment was associated with the increased production of the cytokines interferon γ, tumor necrosis factor α, interleukin 4, and interleukin 13 in the liver and spleen, which are associated with protection against L. donovani.. Our findings show that oral ibrutinib is highly effective for the treatment of VL caused by L. donovani and mediates its antileishmanial activity by promoting host immunity. Therefore, ibrutinib could be a novel host-targeted drug for the treatment of VL.

Topics: Adenine; Administration, Oral; Animals; Cytokines; Disease Models, Animal; Female; Immunity, Cellular; Immunologic Factors; Leishmania donovani; Leishmaniasis, Visceral; Mice; Mice, Inbred BALB C; Piperidines; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Treatment Outcome

Primary CNS lymphomas (PCNSL) are rare and poor prognosis diffuse large B-cell lymphomas. Because of the brain tumor environment and the restricted distribution of drugs in the CNS, specific PCNSL patient-derived orthotopic xenograft (PDOX) models are needed for preclinical research to improve the prognosis of PCNSL patients. PCNSL patient specimens (n = 6) were grafted in the caudate nucleus of immunodeficient nude mice with a 83% rate of success, while subcutaneous implantation in nude mice of human PCNSL sample did not generate lymphoma, supporting the role of the brain microenvironment in the PCNSL physiopathology. PDOXs showed diffuse infiltration of B-cell lymphoma cells in the brain parenchyma. Each model had a unique mutational signature for genes in the BCR and NF-κB pathways and retained the mutational profile of the primary tumor. The models can be stored as cryopreserved biobank. Human IL-10 levels measured in the plasma of PCNSL-PDOX mice showed to be a reliable tool to monitor the tumor burden. Treatment response could be measured after a short treatment with the targeted therapy ibrutinib. In summary, we established a panel of human PCNSL-PDOX models that capture the histological and molecular characteristics of the disease and that proved suitable for preclinical experiments. Our methods of generation and characterization will enable the generation of additional PDOX-PCNSL models, essential tools for cognitive and preclinical drug discovery.

Topics: Adenine; Animals; Caudate Nucleus; Central Nervous System Neoplasms; Disease Models, Animal; Heterografts; Humans; Interleukin-10; Lymphoma, Large B-Cell, Diffuse; Mice; Mice, Nude; Piperidines; Prognosis; Pyrazoles; Pyrimidines; Tumor Burden

CD38 has emerged as a high-impact therapeutic target in multiple myeloma, with the approval of daratumumab (anti-CD38 mAb). The clinical importance of CD38 in patients with chronic lymphocytic leukemia (CLL) has been known for over 2 decades, although it's relevance as a therapeutic target in CLL remains understudied.. In addition to immune-effector mechanisms; daratumumab also induced direct apoptosis of primary CLL cells, which was partially dependent on FcγR cross-linking. For the first time, we demonstrated the influence of CD38 on BCR signaling where interference of CD38 downregulated Syk, BTK, PLCγ2, ERK1/2, and AKT; effects that were further enhanced by addition of ibrutinib. In comparison to single-agent treatment, the combination of ibrutinib and daratumumab resulted in significantly enhanced anti-CLL activity. Overall, our data demonstrate the antitumor mechanisms of daratumumab in CLL; furthermore, we show how cotargeting BTK and CD38 lead to a robust anti-CLL effect, which has clinical implications.

Topics: Adenine; ADP-ribosyl Cyclase 1; Animals; Antibodies, Monoclonal; Antineoplastic Agents; Antineoplastic Agents, Immunological; Apoptosis; Cell Line, Tumor; Disease Models, Animal; Drug Synergism; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Membrane Glycoproteins; Mice; Piperidines; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Receptors, Antigen, B-Cell; Xenograft Model Antitumor Assays

Ibrutinib is a novel antitumor drug that targets Bruton tyrosine kinase for treatment of chronic lymphocytic leukemia. Atrial fibrillation (AF) occurs in 5%-9% of patients during treatment, but the underlying mechanisms remain unclear.. The purpose of this study was to develop a mouse model of ibrutinib-induced AF and investigate its proarrhythmic mechanisms.. In C57BI/6 mice in the ibrutinib and control groups, ibrutinib (25 mg/kg/d) or vehicle (hydroxypropy1-β-cyclodextrin), respectively, was administered orally for 4 weeks. Transesophageal burst stimulation then was used to induced AF. To evaluate the underlying mechanism of AF, cardiac echocardiography was performed. Ca. Compared with the control group, the ibrutinib group showed (1) a higher incidence and longer duration of AF with transesophageal burst stimulation; (2) increased left atrial mass, as indicated by echocardiography; (3) significant myocardial fibrosis in the left atrium on Masson trichrome staining; (4) Ca. The present study established a mouse model of AF by oral administration of ibrutinib for 4 weeks. The arrhythmogenic mechanisms underlying this model likely are associated with structural remodeling and Ca

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Antineoplastic Agents; Atrial Fibrillation; Atrial Remodeling; Calcium; Calcium Signaling; Disease Models, Animal; Echocardiography; Heart Atria; Leukemia, Lymphocytic, Chronic, B-Cell; Mice; Myocytes, Cardiac; Piperidines; Pyrazoles; Pyrimidines

Recent analyses of the genetics of peripheral T-cell lymphoma (PTCL) have shown that a large proportion of cases are derived from normal follicular helper (Tfh) T-cells. The sanroque mouse strain bears a mutation that increases Tfh cell number and heterozygous animals (Roquinsan/+) develop lymphomas similar to human Tfh lymphoma. Here we demonstrate the usefulness of Roquinsan/+ animals as a pre-clinical model of Tfh lymphoma. Long latency of development and incomplete penetrance in this strain suggests the lymphomas are genetically diverse. We carried out preliminary genetic characterisation by whole exome sequencing and detected tumor specific mutations in Hsp90ab1, Ccnb3 and RhoA. Interleukin-2-inducible kinase (ITK) is expressed in Tfh lymphoma and is a potential therapeutic agent. A preclinical study of ibrutinib, a small molecule inhibitor of mouse and human ITK, in established lymphoma was carried out and showed lymphoma regression in 8/12 (67%) mice. Using T2-weighted MRI to assess lymph node volume and diffusion weighted MRI scanning as a measure of function, we showed that treatment increased mean apparent diffusion coefficient (ADC) suggesting cell death, and that change in ADC following treatment correlated with change in lymphoma volume. We suggest that heterozygous sanroque mice are a useful model of Tfh cell derived lymphomas in an immunocompetent animal.

Topics: Adenine; Administration, Oral; Animals; Antineoplastic Agents; Disease Models, Animal; Drug Evaluation, Preclinical; Heterozygote; Humans; Lymph Nodes; Lymphoma, T-Cell, Peripheral; Magnetic Resonance Imaging; Mice; Piperidines; Primary Cell Culture; Pyrazoles; Pyrimidines; T-Lymphocytes, Helper-Inducer; Treatment Outcome; Tumor Cells, Cultured; Ubiquitin-Protein Ligases

Atrial fibrillation is a side effect of ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase used for treatment of B-cell lymphoproliferative disorders. We determined if single (2 or 10 mg/kg), or chronic (14 days) oral ibrutinib followed by 24-hour washout conferred susceptibility to electrically induced arrhythmias in 1-month-old male C57BL/6 mice. A single higher dose of ibrutinib increased arrhythmia inducibility. There was no inducibility difference after chronic dosing with washout. This suggests that high serum drug levels might be responsible for the proarrhythmic effect of ibrutinib and that an altered dosing strategy might mitigate the side effects.

Topics: Adenine; Animals; Atrial Fibrillation; Disease Models, Animal; Disease Susceptibility; Dose-Response Relationship, Drug; Electrocardiography; Male; Mice; Mice, Inbred C57BL; Piperidines; Pulse Therapy, Drug; Pyrazoles; Pyrimidines; Random Allocation; Reference Values; Risk Assessment; Ventricular Fibrillation

Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible lung disease with high mortality rate. The etiology is unknown and treatment choices are limited. Thus, there is great interest to investigate novel agents for IPF therapy. Ibrutinib, BTK, and ITK irreversible inhibitor is a FDA-approved small molecule for the clinical therapy of B cell lymphoma. Its role in pulmonary fibrosis remains unknown. In this study, we investigated the anti-fibrotic activity of ibrutinib. Strikingly, ibrutinib did not inhibit but exacerbated bleomycin-induced pulmonary fibrosis by increased epithelial cell apoptosis, and inflammation in the lung. The upregulated TGF-β and EMT transformation also contributes to enhanced myofibroblast differentiation and ECM deposition. Our findings reveal the detrimental effects of ibrutinib against bleomycin-mediated fibrosis and added to the understanding of IPF pathogenesis.

Topics: Adenine; Animals; Apoptosis; Bleomycin; Disease Models, Animal; Epithelial Cells; Humans; Idiopathic Pulmonary Fibrosis; Inflammation; Mice; Piperidines; Pulmonary Fibrosis; Pyrazoles; Pyrimidines

In diffuse large B-cell lymphoma (DLBCL), activation of the B-cell receptor (BCR) promotes multiple oncogenic signals, which are essential for tumor proliferation. Inhibition of the Bruton's tyrosine kinase (BTK), a BCR downstream target, is therapeutically effective only in a subgroup of patients with DLBCL. Here, we used lymphoma cells isolated from patients with DLBCL to measure the effects of targeted therapies on BCR signaling and to anticipate response. In lymphomas resistant to BTK inhibition, we show that blocking BTK activity enhanced tumor dependencies from alternative oncogenic signals downstream of the BCR, converging on MYC upregulation. To completely ablate the activity of the BCR, we genetically and pharmacologically repressed the activity of the SRC kinases LYN, FYN, and BLK, which are responsible for the propagation of the BCR signal. Inhibition of these kinases strongly reduced tumor growth in xenografts and cell lines derived from patients with DLBCL independent of their molecular subtype, advancing the possibility to be relevant therapeutic targets in broad and diverse groups of DLBCL patients.

Topics: Adenine; Animals; Cell Line, Tumor; Cell Transformation, Neoplastic; Disease Models, Animal; Drug Resistance, Neoplasm; Gene Expression; Genes, myc; Humans; Lymphoma, Non-Hodgkin; Mice; Mice, Knockout; Piperidines; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Receptors, Antigen, B-Cell; Signal Transduction; src-Family Kinases; Xenograft Model Antitumor Assays

The FDA-approved small-molecule drug ibrutinib is an effective targeted therapy for patients with chronic lymphocytic leukemia (CLL). Ibrutinib inhibits Bruton's tyrosine kinase (BTK), a kinase involved in B cell receptor signaling. However, the potential regulation of neuroinflammatory responses in the brain by ibrutinib has not been comprehensively examined.. BV2 microglial cells were treated with ibrutinib (1 μM) or vehicle (1% DMSO), followed by lipopolysaccharide (LPS; 1 μg/ml) or PBS. RT-PCR, immunocytochemistry, and subcellular fractionation were performed to examine the effects of ibrutinib on neuroinflammatory responses. In addition, wild-type mice were sequentially injected with ibrutinib (10 mg/kg, i.p.) or vehicle (10% DMSO, i.p.), followed by LPS (10 mg/kg, i.p.) or PBS, and microglial and astrocyte activations were assessed using immunohistochemistry.. Ibrutinib significantly reduced LPS-induced increases in proinflammatory cytokine levels in BV2 microglial and primary microglial cells but not in primary astrocytes. Ibrutinib regulated TLR4 signaling to alter LPS-induced proinflammatory cytokine levels. In addition, ibrutinib significantly decreased LPS-induced increases in p-AKT and p-STAT3 levels, suggesting that ibrutinib attenuates LPS-induced neuroinflammatory responses by inhibiting AKT/STAT3 signaling pathways. Interestingly, ibrutinib also reduced LPS-induced BV2 microglial cell migration by inhibiting AKT signaling. Moreover, ibrutinib-injected wild-type mice exhibited significantly reduced microglial/astrocyte activation and COX-2 and IL-1β proinflammatory cytokine levels.. Our data provide insights on the mechanisms of a potential therapeutic strategy for neuroinflammation-related diseases.

Topics: Adenine; Animals; Animals, Newborn; Anti-Inflammatory Agents; Cell Line, Transformed; Cells, Cultured; Culture Media, Serum-Free; Cyclooxygenase 2; Cytokines; Disease Models, Animal; Heterocyclic Compounds, 3-Ring; Inflammation; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Microglia; Piperidines; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Rats; Signal Transduction; Wound Healing

Although the treatment paradigm for chronic lymphocytic leukemia (CLL) is rapidly changing, the disease remains incurable, except with allogeneic bone marrow transplantation, and resistance, relapsed disease, and partial responses persist as significant challenges. Recent studies have uncovered roles for epigenetic modification in the regulation of mechanisms contributing to malignant progression of CLL B cells. However, the extent to which epigenetic modifiers can be targeted for therapeutic benefit in CLL patients remains poorly explored. We report for the first time that expression of epigenetic modifier histone deacetylase 6 (HDAC6) is upregulated in CLL patient samples, cell lines, and euTCL1 transgenic mouse models compared with HDAC6 in normal controls. Genetic silencing of HDAC6 conferred survival benefit in euTCL1 mice. Administration of isoform-specific HDAC6 inhibitor ACY738 in the euTCL1 aging and adoptive transfer models deterred proliferation of CLL B cells, delayed disease onset via disruption of B-cell receptor signaling, and sensitized CLL B cells to apoptosis. Furthermore, coadministration of ACY738 and ibrutinib displayed synergistic cell kill against CLL cell lines and improved overall survival compared with either single agent in vivo. These results demonstrate for the first time the therapeutic efficacy of selective HDAC6 inhibition in preclinical CLL models and suggest a rationale for the clinical development of HDAC6 inhibitors for CLL treatment, either alone or in combination with Bruton tyrosine kinase inhibition.

Topics: Adenine; Animals; Antigens, CD19; Apoptosis; B-Lymphocytes; Cell Proliferation; Disease Models, Animal; Gene Silencing; Histone Deacetylase 6; Humans; Hydroxamic Acids; Leukemia, Lymphocytic, Chronic, B-Cell; Leukocytes, Mononuclear; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, SCID; Piperidines; Protein Kinase Inhibitors; Proto-Oncogene Proteins; Pyrazoles; Pyrimidines; Survival Rate

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Disease Models, Animal; Dogs; Drug Approval; Drug Industry; Humans; Lymphoma, Mantle-Cell; Lymphoma, Non-Hodgkin; Male; Molecular Targeted Therapy; Piperidines; Precision Medicine; Pyrazoles; Pyrimidines; United States; United States Food and Drug Administration; Waldenstrom Macroglobulinemia

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Burkitt Lymphoma; Disease Models, Animal; Drug Discovery; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; Lymphoma, B-Cell, Marginal Zone; Lymphoma, Follicular; Lymphoma, Large B-Cell, Diffuse; Lymphoma, Mantle-Cell; Mice; Phosphatidylinositol 3-Kinases; Piperidines; Precision Medicine; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Signal Transduction; Xenograft Model Antitumor Assays

IT-901 is a novel and selective NF-κB inhibitor with promising activity in pre-clinical models. Here we show that treatment of chronic lymphocytic leukemia cells (CLL) with IT-901 effectively interrupts NF-κB transcriptional activity. CLL cells exposed to the drug display elevated mitochondrial reactive oxygen species, which damage mitochondria, limit oxidative phosphorylation and ATP production, and activate intrinsic apoptosis. Inhibition of NF-κB signaling in stromal and myeloid cells, both tumor-supportive elements, fails to induce apoptosis, but impairs NF-κB-driven expression of molecules involved in cell-cell contacts and immune responses, essential elements in creating a pro-leukemic niche. The consequence is that accessory cells do not protect CLL cells from IT-901-induced apoptosis. In this context, IT-901 shows synergistic activity with ibrutinib, arguing in favor of combination strategies. IT-901 is also effective in primary cells from patients with Richter syndrome (RS). Its anti-tumor properties are confirmed in xenograft models of CLL and in RS patient-derived xenografts, with documented NF-κB inhibition and significant reduction of tumor burden. Together, these results provide pre-clinical proof of principle for IT-901 as a potential new drug in CLL and RS.

Topics: Adenine; Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Drug Synergism; Energy Metabolism; Gene Silencing; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Mice; Mitochondria; Molecular Targeted Therapy; NF-kappa B; Piperidines; Pyrazoles; Pyrimidines; Reactive Oxygen Species; Signal Transduction; Xenograft Model Antitumor Assays

Ibrutinib is a Bruton's tyrosine Kinase (BTK) antagonist that inhibits B cell receptor (BCR) signaling. Complete BTK deficiency is associated with absence of B-cells. Ibrutinb is currently approved by FDA for treatment of B-cell malignancies, including Waldenström macroglobulinaemia. We recently carried out studies to determine if ibrutinib could modify alloantibody responses.. A mouse model of allogenic sensitization using a C57BL/6 mouse as the recipient of a skin allograft from an HLA-A2 transgenic mouse was utilized to examine the effects of ibrutinib on alloantibody responses and B cell effector functions. Donor-specific antibody (DSA) levels were measured in a flow-cytometric antibody binding assay. Splenic T and B cell subsets and plasma cells were analyzed in flow cytometry.. Control mice developed peak levels of DSA IgM at day 14 PTx while the ibrutinib treated mice had significantly lower levels of DSA IgM (p=0.0047). Control mice developed HLA.A2-specific IgG antibodies at day 14 (230±60 MFI) and reached peak levels at day 21 (426±61 MFI). In contrast, mice in the treatment group had low levels of HLA.A2-specific IgG at day 14 (109±59 MFI, p=0.004) and day 21 (241±86 MFI, p=0.003). FACS analysis found a reduction of B220. Ibrutinib is effective in suppressing alloantibody responses through blocking BTK-mediated BCR signaling, leading to reduction of B cells and short-lived plasma cells in the spleens. Use of ibrutinib may provide benefits to HLA-sensitized transplant patients for alloantibody suppression.

Topics: Adenine; Animals; B-Lymphocyte Subsets; B-Lymphocytes; Cells, Cultured; Disease Models, Animal; HLA-A2 Antigen; Humans; Immunization; Immunosuppressive Agents; Isoantibodies; Isoantigens; Mice; Mice, Inbred C57BL; Piperidines; Plasma Cells; Pyrazoles; Pyrimidines

Paclitaxel is one of the most widely used antineoplastic drugs in the clinic. Unfortunately, the occurrence of cellular resistance has limited its efficacy and application. The ATP-binding cassette subfamily B member 1 (ABCB1/P-glycoprotein) and subfamily C member 10 (ABCC10/MRP7) are the major membrane protein transporters responsible for the efflux of paclitaxel, constituting one of the most important mechanisms of paclitaxel resistance. Here, we demonstrated that the Bruton tyrosine kinase inhibitor, ibrutinib, significantly enhanced the antitumor activity of paclitaxel by antagonizing the efflux function of ABCB1 and ABCC10 in cells overexpressing these transporters. Furthermore, we demonstrated that the ABCB1 or ABCC10 protein expression was not altered after treatment with ibrutinib for up to 72 hours using Western blot analysis. However, the ATPase activity of ABCB1 was significantly stimulated by treatment with ibrutinib. Molecular docking analysis suggested the binding conformation of ibrutinib within the large cavity of the transmembrane region of ABCB1. Importantly, ibrutinib could effectively enhance paclitaxel-induced inhibition on the growth of ABCB1- and ABCC10-overexpressing tumors in nude athymic mice. These results demonstrate that the combination of ibrutinib and paclitaxel can effectively antagonize ABCB1- or ABCC10-mediated paclitaxel resistance that could be of great clinical interest.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Cell Line, Tumor; Disease Models, Animal; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Drug Synergism; Gene Expression; Humans; Male; Mice; Models, Molecular; Molecular Conformation; Multidrug Resistance-Associated Proteins; Neoplasms; Paclitaxel; Piperidines; Protein Binding; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Tumor Burden; Xenograft Model Antitumor Assays

We have reported that a novel isoform of BTK (BTK-C) expressed in breast cancer protects these cells from apoptosis. In this study, we show that recently developed inhibitors of BTK, such as ibrutinib (PCI-32765), AVL-292, and CGI-1746, reduce breast cancer cell survival and prevent drug-resistant clones from arising. Ibrutinib treatment impacts HER2(+) breast cancer cell viability at lower concentrations than the established breast cancer therapeutic lapatinib. In addition to inhibiting BTK, ibrutinib, but not AVL-292 and CGI-1746, efficiently blocks the activation of EGFR, HER2, ErbB3, and ErbB4. Consequently, the activation of AKT and ERK signaling pathways are also blocked leading to a G1-S cell-cycle delay and increased apoptosis. Importantly, inhibition of BTK prevents activation of the AKT signaling pathway by NRG or EGF that has been shown to promote growth factor-driven lapatinib resistance in HER2(+) breast cancer cells. HER2(+) breast cancer cell proliferation is blocked by ibrutinib even in the presence of these factors. AVL-292, which has no effect on EGFR family activation, prevents NRG- and EGF-dependent growth factor-driven resistance to lapatinib in HER2(+) breast cancer cells. In vivo, ibrutinib inhibits HER2(+) xenograft tumor growth. Consistent with this, immunofluorescence analysis of xenograft tumors shows that ibrutinib reduces the phosphorylation of HER2, BTK, Akt, and Erk and histone H3 and increases cleaved caspase-3 signals. As BTK-C and HER2 are often coexpressed in human breast cancers, these observations indicate that BTK-C is a potential therapeutic target and that ibrutinib could be an effective drug especially for HER2(+) breast cancer. Mol Cancer Ther; 15(9); 2198-208. ©2016 AACR.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Antineoplastic Agents; Apoptosis; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Epidermal Growth Factor; Female; Gene Expression; Humans; Lapatinib; MAP Kinase Signaling System; Mice; Neuregulin-1; Piperidines; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Proto-Oncogene Proteins c-akt; Pyrazoles; Pyrimidines; Quinazolines; Receptor, ErbB-2; Signal Transduction; Tumor Burden; Xenograft Model Antitumor Assays

Deletion of the short-arm of chromosome 17 (17p-) is one of the most critical genetic alterations used in chronic lymphocytic leukemia (CLL) risk stratification. The tumor suppressor TP53 maps to this region, and its loss or mutation accelerates CLL progression, hampers response to chemotherapy and shortens survival. Although florescent in situ hybridization analyses for 17p deletions are routinely performed during clinical diagnoses, p53 mutational status is often unexamined. Given the limited clinical data that exists for frontline treatment of patients with CLL harboring TP53 mutations, there is a need to understand the biology of CLL with TP53 mutations and identify treatment strategies for this subset of patients. Herein, we used a CLL mouse model (Eμ-TCL1) harboring one of the most common TP53 hot-spot mutations observed in CLL (p53(R172H), corresponding to p53(R175H) in humans) to evaluate its impact on disease progression, survival, response to therapy and loss of the remaining wild-type Trp53 allele following ibrutinib treatment. We show that ibrutinib was effective in increasing survival, activating cellular programs outside the p53 pathway and did not place selective pressure on the remaining wild-type Trp53 allele. These data provide evidence that ibrutinib acts as an effective treatment for aggressive forms of CLL with TP53 mutations.

Topics: Adenine; Angiopoietin-1; Animals; Apoptosis; Cell Line, Tumor; Cell Proliferation; Cluster Analysis; Disease Models, Animal; Disease Progression; Gene Expression Profiling; Humans; Kaplan-Meier Estimate; Leukemia, Lymphocytic, Chronic, B-Cell; Loss of Heterozygosity; Mice; Mice, Knockout; Mutation; Piperidines; Prognosis; Protein Kinase Inhibitors; Proto-Oncogene Proteins; Pyrazoles; Pyrimidines; Signal Transduction; Tumor Suppressor Protein p53; Xenograft Model Antitumor Assays

Despite the therapeutic efficacy of ibrutinib in chronic lymphocytic leukemia (CLL), complete responses are infrequent, and acquired resistance to Bruton agammaglobulinemia tyrosine kinase (BTK) inhibition is being observed in an increasing number of patients. Combination regimens that increase frequency of complete remissions, accelerate time to remission, and overcome single agent resistance are of considerable interest. We previously showed that the XPO1 inhibitor selinexor is proapoptotic in CLL cells and disrupts B-cell receptor signaling via BTK depletion. Herein we show the combination of selinexor and ibrutinib elicits a synergistic cytotoxic effect in primary CLL cells and increases overall survival compared with ibrutinib alone in a mouse model of CLL. Selinexor is effective in cells isolated from patients with prolonged lymphocytosis following ibrutinib therapy. Finally, selinexor is effective in ibrutinib-refractory mice and in a cell line harboring the BTK C481S mutation. This is the first report describing the combined activity of ibrutinib and selinexor in CLL, which represents a new treatment paradigm and warrants further evaluation in clinical trials of CLL patients including those with acquired ibrutinib resistance.

Topics: Adenine; Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Drug Resistance, Neoplasm; Drug Synergism; Humans; Hydrazines; Leukemia, Lymphocytic, Chronic, B-Cell; Mice; Piperidines; Pyrazoles; Pyrimidines; Triazoles; Xenograft Model Antitumor Assays

Chronic lymphocytic leukemia (CLL) is characterized by constitutive activation of the B-cell receptor (BCR) signaling pathway, but variable responsiveness of the BCR to antigen ligation. Bruton's tyrosine kinase (BTK) shows constitutive activity in CLL and is the target of irreversible inhibition by ibrutinib, an orally bioavailable kinase inhibitor that has shown outstanding activity in CLL. Early clinical results in CLL with other reversible and irreversible BTK inhibitors have been less promising, however, raising the question of whether BTK kinase activity is an important target of ibrutinib and also in CLL. To determine the role of BTK in CLL, we used patient samples and the Eμ-TCL1 (TCL1) transgenic mouse model of CLL, which results in spontaneous leukemia development. Inhibition of BTK in primary human CLL cells by small interfering RNA promotes apoptosis. Inhibition of BTK kinase activity through either targeted genetic inactivation or ibrutinib in the TCL1 mouse significantly delays the development of CLL, demonstrating that BTK is a critical kinase for CLL development and expansion and thus an important target of ibrutinib. Collectively, our data confirm the importance of kinase-functional BTK in CLL.

Topics: Adenine; Adult; Agammaglobulinaemia Tyrosine Kinase; Animals; Apoptosis; Cell Survival; Disease Models, Animal; Female; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Mice, Transgenic; Piperidines; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; RNA, Small Interfering; Signal Transduction

Bone-resorbing osteoclasts play an essential role in normal bone homeostasis, as well as in various bone disorders such as osteoporosis and rheumatoid arthritis. Previously we showed that the Tec family of tyrosine kinases is essential for the differentiation of osteoclasts and the inhibition of Btk is a promising strategy for the prevention of the bone loss in osteoclast-associated bone disorders. Here we demonstrate that an orally available Btk inhibitor, ibrutinib (PCI-32765), suppresses osteoclastic bone resorption by inhibiting both osteoclast differentiation and function. Ibrutinib downregulated the expression of NFATc1, the key transcription factor for osteoclastogenesis, and disrupted the formation of the actin ring in mature osteoclasts. In addition, genome-wide screening revealed that Btk regulates the expression of the genes involved in osteoclast differentiation and function in both an NFATc1-dependent and -independent manner. Finally, we showed that ibrutinib administration ameliorated the bone loss that developed in a RANKL-induced osteoporosis mouse model. Thus, this study suggests ibrutinib to be a promising therapeutic agent for osteoclast-associated bone diseases.

Topics: Adenine; Administration, Oral; Agammaglobulinaemia Tyrosine Kinase; Animals; Bone Resorption; Cell Differentiation; Disease Models, Animal; Female; Gene Expression Regulation; Mice; Mice, Inbred C57BL; Osteoblasts; Osteoclasts; Osteoporosis; Piperidines; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; RANK Ligand

Our findings therefore provide a strong rationale for investigating Btk inhibitors in MM and WM to target both tumor cells and their supporting BM microenvironment and thereby both suppress tumor cell growth and abrogate MM-induced bone disease.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Cell Growth Processes; Disease Models, Animal; Humans; Mice; Molecular Targeted Therapy; Multiple Myeloma; Piperidines; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Waldenstrom Macroglobulinemia

Myc, a pleiotropic transcription factor that is deregulated and/or overexpressed in most human cancers, instructs multiple extracellular programs that are required to sustain the complex microenvironment needed for tumor maintenance, including remodeling of tumor stroma, angiogenesis, and inflammation. We previously showed in a model of pancreatic β-cell tumorigenesis that acute Myc activation in vivo triggers rapid recruitment of mast cells to the tumor site and that this is absolutely required for angiogenesis and macroscopic tumor expansion. Moreover, systemic inhibition of mast cell degranulation with sodium cromoglycate induced death of tumor and endothelial cells in established tumors. Hence, mast cells are required both to establish and to maintain the tumors. Whereas this intimates that selective inhibition of mast cell function could be therapeutically efficacious, cromoglycate is not a practical drug for systemic delivery in humans, and no other systemic inhibitor of mast cell degranulation has hitherto been available. PCI-32765 is a novel inhibitor of Bruton tyrosine kinase (Btk) that blocks mast cell degranulation and is currently in clinical trial as a therapy for B-cell non-Hodgkin lymphoma. Here, we show that systemic treatment of insulinoma-bearing mice with PCI-32765 efficiently inhibits Btk, blocks mast cell degranulation, and triggers collapse of tumor vasculature and tumor regression. These data reinforce the notion that mast cell function is required for maintenance of certain tumor types and indicate that the Btk inhibitor PCI-32765 may be useful in treating such diseases.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Cell Degranulation; Cell Proliferation; Cell Transformation, Neoplastic; Disease Models, Animal; Down-Regulation; Genes, myc; Insulinoma; Mast Cells; Mice; Mice, Transgenic; Models, Theoretical; Pancreatic Neoplasms; Piperidines; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Tumor Cells, Cultured

Activation of the B-cell antigen receptor (BCR) signaling pathway contributes to the initiation and maintenance of B-cell malignancies and autoimmune diseases. The Bruton tyrosine kinase (Btk) is specifically required for BCR signaling as demonstrated by human and mouse mutations that disrupt Btk function and prevent B-cell maturation at steps that require a functional BCR pathway. Herein we describe a selective and irreversible Btk inhibitor, PCI-32765, that is currently under clinical development in patients with B-cell non-Hodgkin lymphoma. We have used this inhibitor to investigate the biologic effects of Btk inhibition on mature B-cell function and the progression of B cell-associated diseases in vivo. PCI-32765 blocked BCR signaling in human peripheral B cells at concentrations that did not affect T cell receptor signaling. In mice with collagen-induced arthritis, orally administered PCI-32765 reduced the level of circulating autoantibodies and completely suppressed disease. PCI-32765 also inhibited autoantibody production and the development of kidney disease in the MRL-Fas(lpr) lupus model. Occupancy of the Btk active site by PCI-32765 was monitored in vitro and in vivo using a fluorescent affinity probe for Btk. Active site occupancy of Btk was tightly correlated with the blockade of BCR signaling and in vivo efficacy. Finally, PCI-32765 induced objective clinical responses in dogs with spontaneous B-cell non-Hodgkin lymphoma. These findings support Btk inhibition as a therapeutic approach for the treatment of human diseases associated with activation of the BCR pathway.

Topics: Adenine; Administration, Oral; Agammaglobulinaemia Tyrosine Kinase; Animals; Arthritis, Experimental; Autoantibodies; Autoimmune Diseases; B-Lymphocytes; Benzofurans; Disease Models, Animal; Dogs; Humans; Lymphocyte Activation; Lymphoma, B-Cell; Mice; Piperidines; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Receptors, Antigen, B-Cell; Signal Transduction; Treatment Outcome

Topics: Adenosine Triphosphate; Agammaglobulinaemia Tyrosine Kinase; Amino Acid Sequence; Animals; Antirheumatic Agents; Arthritis, Rheumatoid; Binding Sites; Disease Models, Animal; Drug Design; Molecular Sequence Data; Oligopeptides; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Rodentia; Structure-Activity Relationship