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Okhuysen PC, Ramesh MS, Louie T, Kiknadze N, Torre-Cisneros J, de Oliveira CM, Van Steenkiste C, Stychneuskaya A, Garey KW, Garcia-Diaz J, Li J, Duperchy E, Chang BY, Sukbuntherng J, Montoya JG, Styles L, Clow F, James D, Dubberke ER, Wilcox M. A Randomized, Double-Blind, Phase 3 Safety and Efficacy Study of Ridinilazole Versus Vancomycin for Treatment of Clostridioides difficile Infection: Clinical Outcomes With Microbiome and Metabolome Correlates of Response. Clin Infect Dis 2024:ciad792. [PMID: 38305378 DOI: 10.1093/cid/ciad792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Indexed: 02/03/2024] Open
Abstract
BACKGROUND Exposure to antibiotics predisposes to dysbiosis and Clostridioides difficile infection (CDI) that can be severe, recurrent (rCDI), and life-threatening. Nonselective drugs that treat CDI and perpetuate dysbiosis are associated with rCDI, in part due to loss of microbiome-derived secondary bile acid (SBA) production. Ridinilazole is a highly selective drug designed to treat CDI and prevent rCDI. METHODS In this phase 3 superiority trial, adults with CDI, confirmed with a stool toxin test, were randomized to receive 10 days of ridinilazole (200 mg twice daily) or vancomycin (125 mg 4 times daily). The primary endpoint was sustained clinical response (SCR), defined as clinical response and no rCDI through 30 days after end of treatment. Secondary endpoints included rCDI and change in relative abundance of SBAs. RESULTS Ridinilazole and vancomycin achieved an SCR rate of 73% versus 70.7%, respectively, a treatment difference of 2.2% (95% CI: -4.2%, 8.6%). Ridinilazole resulted in a 53% reduction in recurrence compared with vancomycin (8.1% vs 17.3%; 95% CI: -14.1%, -4.5%; P = .0002). Subgroup analyses revealed consistent ridinilazole benefit for reduction in rCDI across subgroups. Ridinilazole preserved microbiota diversity, increased SBAs, and did not increase the resistome. Conversely, vancomycin worsened CDI-associated dysbiosis, decreased SBAs, increased Proteobacteria abundance (∼3.5-fold), and increased the resistome. CONCLUSIONS Although ridinilazole did not meet superiority in SCR, ridinilazole greatly reduced rCDI and preserved microbiome diversity and SBAs compared with vancomycin. These findings suggest that treatment of CDI with ridinilazole results in an earlier recovery of gut microbiome health. Clinical Trials Registration.Ri-CoDIFy 1 and 2: NCT03595553 and NCT03595566.
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Affiliation(s)
- Pablo C Okhuysen
- Department of Infectious Diseases, Infection Control, and Employee Heatlh, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | | | - Thomas Louie
- Foothills Medical Center and University of Calgary, Calgary, Canada
| | | | - Julian Torre-Cisneros
- Reina Sofia University Hospital-IMIBIC, University of Córdoba, CIBERINFEC, Cordoba, Spain
| | | | | | | | - Kevin W Garey
- University of Houston College of Pharmacy, Houston, Texas, USA
| | | | - Jianling Li
- Summit Therapeutics, Menlo Park, California, USA
| | | | | | | | - Jose G Montoya
- Summit Therapeutics, Menlo Park, California, USA
- Dr. Jack S. Remington Laboratory for Specialty Diagnostics, Palo Alto Medical Foundation, Palo Alto, California, USA
| | - Lori Styles
- Summit Therapeutics, Menlo Park, California, USA
| | - Fong Clow
- Summit Therapeutics, Menlo Park, California, USA
| | | | - Erik R Dubberke
- Washington University School of Medicine, St.Louis, Missouri, USA
| | - Mark Wilcox
- Leeds Teaching Hospitals and University of Leeds, School of Medicine, Leeds, United Kingdom
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Ninomoto J, Mokatrin A, Kinoshita T, Marimpietri C, Barrett TD, Chang BY, Sukbuntherng J, James DF, Crowther M. Effects of ibrutinib on in vitro platelet aggregation in blood samples from healthy donors and donors with platelet dysfunction. ACTA ACUST UNITED AC 2020; 25:112-117. [PMID: 32131714 DOI: 10.1080/16078454.2020.1730080] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Background: Ibrutinib, a first-in-class, once-daily inhibitor of Bruton's tyrosine kinase (BTK), is approved in the US and EU for the treatment of various B-cell malignancies. In clinical studies, BTK inhibitors have been associated with increased bleeding risk, which may result from BTK inhibition in platelets.Methods: To better understand the mechanism of ibrutinib in bleeding events, we isolated platelet-rich plasma from healthy donors (n = 8) and donors with conditions associated with impaired platelet function or with potentially increased bleeding risk (on hemodialysis, taking aspirin, or taking warfarin; n = 8 each cohort) and used light transmission aggregometry to assess platelet aggregation in vitro after exposure to escalating concentrations of ibrutinib, spanning and exceeding the pharmacologic range of clinical exposure.Results: Platelet aggregation was induced by agonists of 5 major platelet receptors: adenosine diphosphate (ADP), thrombin receptor-activating peptide 6 (TRAP6), ristocetin, collagen, or arachidonic acid (AA). Platelet aggregation induced by ADP, TRAP6, ristocetin, and AA was not meaningfully inhibited by the maximal concentrations of ibrutinib (10 µM). In contrast, collagen-induced platelet aggregation was dose-dependently inhibited by ibrutinib in all donor cohorts (maximum aggregation % with 10 μM ibrutinib, -64% to -83% of agonist activity compared to control agonist samples but without ibrutinib).Conclusion: These results confirm prior reports and support a mechanistic role for the inhibition of collagen-induced platelet aggregation in bleeding events among susceptible individuals receiving ibrutinib therapy.
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Affiliation(s)
- Joi Ninomoto
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA, USA
| | - Ahmad Mokatrin
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA, USA
| | | | | | | | - Betty Y Chang
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA, USA
| | | | | | - Mark Crowther
- Department of Medicine, McMaster University, Hamilton, Canada
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Chen J, Kinoshita T, Gururaja T, Sukbuntherng J, James D, Lu D, Whang J, Versele M, Chang BY. The effect of Bruton's tyrosine kinase (BTK) inhibitors on collagen-induced platelet aggregation, BTK, and tyrosine kinase expressed in hepatocellular carcinoma (TEC). Eur J Haematol 2018; 101:604-612. [PMID: 30030853 DOI: 10.1111/ejh.13148] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 02/28/2024]
Abstract
OBJECTIVES Bruton's tyrosine kinase (BTK) and tyrosine kinase expressed in hepatocellular carcinoma (TEC) are expressed by human platelets. These kinases participate in platelet activation through the collagen receptor glycoprotein VI and may perform overlapping functions. In clinical studies, BTK inhibitors (ibrutinib, acalabrutinib, tirabrutinib, zanubrutinib) have been associated with increased bleeding risk, which may result from inhibition of BTK alone or of both BTK and TEC, although the role of TEC in bleeding risk remains unclear. METHODS Here, in vitro catalytic and binding activities of ibrutinib and acalabrutinib were determined with four assay systems. Platelet aggregation assays determined inhibitor potency and its relationship to selectivity between BTK and TEC. RESULTS Neither inhibitor was substantially more selective for BTK over TEC. The potencies at which BTK inhibitors suppressed platelet aggregation correlated with the potencies in on-target BTK assays, including those in cells. At clinically relevant plasma concentration, ibrutinib, acalabrutinib, and tirabrutinib inhibited collagen-induced platelet aggregation to a similar extent, despite differing in vitro IC50 s. CONCLUSIONS Our results suggest BTK inhibition is the primary driver for inhibition of platelet aggregation. The subtle differences between these inhibitors suggest only randomized, double-blind, placebo-controlled clinical studies can fully address the bleeding risks of different BTK inhibitors.
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Affiliation(s)
- Jun Chen
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA, USA
| | | | | | | | - Danelle James
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA, USA
| | - Daniel Lu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA, USA
| | - Jennifer Whang
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA, USA
| | | | - Betty Y Chang
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA, USA
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Abstract
We show that the excitation probability of a state within a manifold of levels undergoes Rabi oscillations with the frequency determined by the energy difference between the states and not by the pulse area, for sufficiently strong pulses. The population and coherence remains in the two-level subsystem formed by the initial and target state even at Rabi frequencies exceeding the energy difference. The observed dynamics can be useful in nonlinear spectroscopy and quantum state preparation.
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Affiliation(s)
- B Y Chang
- School of Chemistry (BK21), Seoul National University, Seoul 08826, Republic of Korea
| | - I R Sola
- Departamento de Química Física I, Universidad Complutense, 28040 Madrid, Spain
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Kuo HP, Hsieh S, Sirisawad M, Chen CT, Cheung LW, Schweighofer KJ, Hsu CL, Fu CL, Liu J, Wu S, Eckert K, Wang H, Apatira M, Dhami K, Kwei K, Hsu J, Chang BY. Abstract 4197: Interaction of B lymphoma cells with the microenvironment affects ibrutinib sensitivity. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction:
The cellular microenvironment plays a key role in the pathogenesis of B-cell malignancies (Amé-Thomas, Blood 2007; Podar, Leukemia 2009). Bone marrow stromal cell interactions can provide survival signals to CLL cells (Kurtova, Blood 2009), and stromal cell gene signatures and markers can predict survival outcomes and add prognostic value, respectively, for patients with DLBCL (Lenz, NEJM 2008; Meyer, Am J Clin Pathol 2011). Ibrutinib (ibr), a first-in-class, oral, once-daily inhibitor of Bruton’s tyrosine kinase, has demonstrated single-agent activity in R/R DLBCL (Wilson, Nat Med 2015). In this study, we established an in vitro coculture system and report the effects of stromal cells on ABC-DLBCL cells and their sensitivity to ibr.
Methods: The effect of ibr on cell growth was evaluated by luminescent cell viability assay. Flow cytometry was used to evaluate the effect of ibr on cell death in different cell populations. Live-cell imaging detected drug effects on apoptosis at different time points. Gene expression levels in B lymphoma cells were examined by quantitative PCR and NanoString panels. Human cytokines/chemokines were quantified using MILLIPLEX® MAP Kit.
Results: Reduced ibr sensitivity was observed in TMD8 DLBCL cells cocultured with HS-5 bone marrow-derived stromal cells. HS-5 cells protected TMD8 cells from ibr-induced apoptosis. Treatment with ibr induced TNFSF10 expression only in TMD8 cells without HS-5 coculture, providing a survival mechanism for escape of ibr-induced cell death. In addition, coculturing with HS-5 decreased surface expression of CD20 but not CD19. Several cytokines/chemokines showed differential expression in the coculture system (increased CCL22 and IL-10; decreased CCL4 and TNFβ). Reduced expression of BCR signaling-related miR-155 was observed in ABC-DLBCL and CLL cell lines with HS-5 coculture, suggesting downregulation of BCR signaling in these cells. The adhesion molecule, SELL, showed decreased expression in the ABC-DLBCL cells cultured with HS-5 as well as in ibr-resistant TMD8 cells, consistent with our observation that ABC-DLBCL patients with poor responses (PD+SD) to ibr have lower SELL expression in their tumor samples. We further assessed expression levels of amino acid metabolism-related genes and demonstrated significant increases of ASS1 and TDO2 in the TMD8 cells cocultured with HS-5. Expression levels of amino acid metabolism-related genes varied across patients with different responses to ibr, further suggesting the importance of amino acid levels in the tumor microenvironment and ibr response.
Conclusions: The changes in ABC-DLBCL cells cocultured with stromal cells identified here may provide new insights into cellular cross-talk in the microenvironment. Further investigation into cell-cell interactions and ibr may help stratify patient populations and provide new therapeutic strategies.
Citation Format: Hsu-Ping Kuo, Sidney Hsieh, Mint Sirisawad, Chun-Te Chen, Leo W. Cheung, Karl J. Schweighofer, Chia-Lin Hsu, Chi-Ling Fu, Jing Liu, Shiquan Wu, Karl Eckert, Hugh Wang, Mutiah Apatira, Kamaldeep Dhami, Kevin Kwei, Jeff Hsu, Betty Y. Chang. Interaction of B lymphoma cells with the microenvironment affects ibrutinib sensitivity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4197. doi:10.1158/1538-7445.AM2017-4197
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Affiliation(s)
- Hsu-Ping Kuo
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Sidney Hsieh
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | | | - Chun-Te Chen
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Leo W. Cheung
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | | | - Chia-Lin Hsu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Chi-Ling Fu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Jing Liu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Shiquan Wu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Karl Eckert
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Hugh Wang
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | | | | | - Kevin Kwei
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Jeff Hsu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
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Chen J, Chen CT, Liu J, Hsu J, Kinoshita T, Chang BY. Abstract 167: Ibrutinib regulates tumor microenvironment and enhances response to everolimus in renal cell carcinoma mouse models. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Ibrutinib (ibr), a first-in-class, once-daily, oral inhibitor of Bruton’s tyrosine kinase (BTK), is indicated for the treatment of patients with CLL/SLL, MCL and WM. Ibr also inhibits EGFR/HER2 and has demonstrated efficacy against EGFR+ NSCLC and HER2+ breast cancer in vitro and in xenograft models (Gao 2014; Chen 2016). Further, ibr modulated host immunity and enhanced anti-PD-L1 activity in solid tumor models otherwise insensitive to BTK or HER kinase inhibition (Sagiv-Barfi 2015), suggesting that ibr may be active in renal cell carcinoma (RCC) via multiple mechanisms. Here we determined the impact of ibr alone and in combination with everolimus (eve) on tumor growth and the tumor microenvironment in syngeneic and xenograft RCC mouse models.
Methods: Cell proliferation was determined with CellTiter-Glo using a 3-day treatment regimen. Subcutaneous implantation of 786-0 and Renca cells established xenograft and syngeneic models in nude and immune-competent mice. Treatment started when tumor volume reached 150 mm3 (786-0) or 55 mm3 (Renca) and was measured twice weekly. Immunophenotying of tumor infiltrates was determined by flow cytometry. For Treg differentiation, magnetically-sorted CD4+CD25- mouse splenic T cells were stimulated with anti-CD3/CD28 antibodies and TGF-β1 for 5 days.
Results: Ibr significantly inhibited the growth of syngeneic Renca tumors (TGI%=32.4 at Day 19, p≤0.05) in Balb/c mice and enhanced the efficacy of eve, although Renca cells were not sensitive to ibr in vitro. The combination significantly reduced the numbers of splenic and tumor Tregs in addition to reducing PD-1 expression on tumor CD8+ T cells. Consistently, in vitro Treg differentiation assays revealed that, while the combination of ibr and eve significantly reduced Treg differentiation, either drug alone showed little effect. In 786-0 xenograft model, ibr alone slowed tumor growth in a subgroup of mice and significantly enhanced the effect of eve (p≤0.05 or 0.01). To identify whether BTK or EGFR/HER2 is the target, CGI-1746, a BTK inhibitor, and lapatinib, an EGFR/HER2 inhibitor, were tested. Surprisingly, both CGI-1746 and lapatinib were active in inhibiting tumor growth (TGI%=26.7 or 37.6 respectively, p≤0.05 or 0.01), and slightly potentiated the efficacy of eve. However, consistent with ibr results, neither CGI-1746 nor lapatinib showed any effect on the cell growth of 786-0 cells.
Conclusion: This study suggests that ibr has antitumor activity against RCC alone and when combined with eve in animal models. This effect may be mediated by modulation of the tumor microenvironment, such as inhibiting Treg differentiation and suppressing PD-1 expression on CD8+ T cells, and both BTK and EGFR/HER2 are involved. Further investigation is needed to clarify the mechanism of action, but the results here provide a rationale for ibr as a novel agent for RCC in combination with mTOR inhibitors.
Citation Format: Jun Chen, Chun-Te Chen, Jing Liu, Jeff Hsu, Taisei Kinoshita, Betty Y. Chang. Ibrutinib regulates tumor microenvironment and enhances response to everolimus in renal cell carcinoma mouse models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 167. doi:10.1158/1538-7445.AM2017-167
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Affiliation(s)
- Jun Chen
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Chun-Te Chen
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Jing Liu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
| | - Jeff Hsu
- Pharmacyclics, LLC, an AbbVie Company, Sunnyvale, CA
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Solman I, You H, Taylor M, Dubovsky JA, Kipps TJ, Burger JA, Lal I, Chang BY, James DF, Hill JS. Ibrutinib vs chlorambucil: Immunophenotypic and quantitative impacts on circulating immune cells in chronic lymphocytic leukemia (CLL). J Clin Oncol 2017. [DOI: 10.1200/jco.2017.35.15_suppl.7524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7524 Background: Ibrutinib (ibr), a first-in-class, once-daily inhibitor of Bruton’s tyrosine kinase, is indicated by FDA for treatment (Tx) of patients (pts) with CLL. Following the outcome of the RESONATE-2 trial, ibr was approved as the first chemotherapy-free Tx option for treatment-naïve (TN) pts. In this study, ibr reduced the risk of progression or death by 84% compared with chlorambucil (chl). To assess the impact of ibrutinib vs this traditional chemotherapeutic agent on the immune system, quantitative changes in circulating cells were studied throughout the first year of Tx. Methods: Immunophenotypic analyses were performed by flow cytometry on peripheral blood to assess lymphoid and myeloid cells of TN CLL pts who received 420 mg ibr once daily (n=50) or 0.5-0.8 mg/kg chl twice a month (n=30). Medians of statistically significant changes (p<0.05, Wilcoxon test) in absolute counts of 1-year paired samples (pre-dose vs 1-year) are reported. Results: Chl progressively reduced circulating B, T, NK, NKT cells, myeloid derived suppressor cells (MDSC), and monocytes by 69%-99%. All development stages of CD4+ and CD8+ T cells, except stem cell memory T cells (TSCM), decreased by 51%-90%. Regulatory T cells (Treg) and PD1+ T cells also decreased similarly; however, long-term activated T cells (TLA) were not impacted. On the other hand, ibr mainly reduced B cells (90%), MDSC (61%) and some T cells, specifically TLA, PD1+ T cells, Treg and effector T cells (27-52%). Naïve T cells, TSCM, central memory T cells and NK cells were spared throughout the full year of Tx. Classical monocytes were increased (+187%), while non-classical monocytes and intermediate monocytes remained relatively steady. Conclusions: Chl, a traditional chemotherapy, affected non-specifically most immune cell subsets in circulation, although surprisingly it did not affect TLA which have been reported as dysfunctional in CLL. Ibr represents a more targeted Tx approach than cytotoxic chemotherapy; essentially B cells, abnormal T subsets (TLA, PD1+T, Treg) and pro-tumor MDSCs were reduced. However, ibr preserved naïve T cells, NK cells and monocytes, which are important for mounting anti-tumor responses. Clinical trial information: NCT01722487.
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Affiliation(s)
| | - Hana You
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | | | | | - Thomas J. Kipps
- University of California San Diego Moores Cancer Center, La Jolla, CA
| | | | - Indu Lal
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
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Kuo HP, Ezell SA, Schweighofer KJ, Cheung LWK, Hsieh S, Apatira M, Sirisawad M, Eckert K, Hsu SJ, Chen CT, Beaupre DM, Versele M, Chang BY. Combination of Ibrutinib and ABT-199 in Diffuse Large B-Cell Lymphoma and Follicular Lymphoma. Mol Cancer Ther 2017; 16:1246-1256. [PMID: 28428442 DOI: 10.1158/1535-7163.mct-16-0555] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 02/01/2017] [Accepted: 04/14/2017] [Indexed: 11/16/2022]
Abstract
Diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma are the most prevalent B-lymphocyte neoplasms in which abnormal activation of the Bruton tyrosine kinase (BTK)-mediated B-cell receptor signaling pathway contributes to pathogenesis. Ibrutinib is an oral covalent BTK inhibitor that has shown some efficacy in both indications. To improve ibrutinib efficacy through combination therapy, we first investigated differential gene expression in parental and ibrutinib-resistant cell lines to better understand the mechanisms of resistance. Ibrutinib-resistant TMD8 cells had higher BCL2 gene expression and increased sensitivity to ABT-199, a BCL-2 inhibitor. Consistently, clinical samples from ABC-DLBCL patients who experienced poorer response to ibrutinib had higher BCL2 gene expression. We further demonstrated synergistic growth suppression by ibrutinib and ABT-199 in multiple ABC-DLBCL, GCB-DLBCL, and follicular lymphoma cell lines. The combination of both drugs also reduced colony formation, increased apoptosis, and inhibited tumor growth in a TMD8 xenograft model. A synergistic combination effect was also found in ibrutinib-resistant cells generated by either genetic mutation or drug treatment. Together, these findings suggest a potential clinical benefit from ibrutinib and ABT-199 combination therapy. Mol Cancer Ther; 16(7); 1246-56. ©2017 AACR.
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Affiliation(s)
- Hsu-Ping Kuo
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Scott A Ezell
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Karl J Schweighofer
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Leo W K Cheung
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Sidney Hsieh
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Mutiah Apatira
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Mint Sirisawad
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Karl Eckert
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Ssucheng J Hsu
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Chun-Te Chen
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Darrin M Beaupre
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | | | - Betty Y Chang
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California.
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Kuo HP, Ezell SA, Hsieh S, Schweighofer KJ, Cheung LW, Wu S, Apatira M, Sirisawad M, Eckert K, Liang Y, Hsu J, Chen CT, Beaupre D, Chang BY. The role of PIM1 in the ibrutinib-resistant ABC subtype of diffuse large B-cell lymphoma. Am J Cancer Res 2016; 6:2489-2501. [PMID: 27904766 PMCID: PMC5126268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023] Open
Abstract
Diffuse large B cell lymphoma (DLBCL) is a heterogeneous lymphoma and the most common subtype of non-Hodgkin lymphoma, accounting for roughly 30% of newly diagnosed cases in the United States. DLBCL can be separated into the activated B cell-like (ABC) and germinal center B cell-like (GCB) subtypes, with distinct gene expression profiles, oncogenic aberrations, and clinical outcomes. ABC-DLBCL is characterized by chronically active B-cell receptor (BCR) signaling that can be modulated by Bruton's tyrosine kinase (BTK) activity. Thus, BTK serves as an attractive therapeutic target in this type of B-cell malignancy. Ibrutinib, a first-in-class, orally available covalent BTK inhibitor, has demonstrated clinical activity in several B-cell leukemias and lymphomas. A phase 1/2 clinical trial of single-agent ibrutinib in relapsed and refractory DLBCL patients revealed an overall response rate of 37% in ABC-DLBCL patients. However, responses to kinase-directed therapies are often limited by emerging resistance mechanisms that bypass the therapeutic target. Here we report the discovery of point mutations within the kinase PIM1 that reduce sensitivity to ibrutinib in ABC-DLBCL. These mutations stabilize PIM1 and affect upstream regulators and downstream targets of NF-κB signaling. The introduction of mutant PIM1 into an ABC-DLBCL cell line, TMD8, increased colony formation and decreased sensitivity to ibrutinib. In addition, ibrutinib-resistant cell lines generated by prolonged ibrutinib exposure in vitro upregulated PIM1 expression, consistent with a role for PIM1 in antagonizing ibrutinib activity. The combination of a pan-PIM inhibitor with ibrutinib synergistically inhibited proliferation in vitro and tumor growth in vivo. Together, these data provide a rationale for combining BTK and PIM1 inhibition in the treatment of ABC-DLBCL.
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Affiliation(s)
- Hsu-Ping Kuo
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Scott A Ezell
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Sidney Hsieh
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Karl J Schweighofer
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Leo Wk Cheung
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Shiquan Wu
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Mutiah Apatira
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Mint Sirisawad
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Karl Eckert
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Yu Liang
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Jeff Hsu
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Chun-Te Chen
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Darrin Beaupre
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
| | - Betty Y Chang
- Department of Research, Pharmacyclics, LLC, an AbbVie Company Sunnyvale, CA, USA
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Chen J, Kinoshita T, Sukbuntherng J, Chang BY, Elias L. Ibrutinib Inhibits ERBB Receptor Tyrosine Kinases and HER2-Amplified Breast Cancer Cell Growth. Mol Cancer Ther 2016; 15:2835-2844. [PMID: 27678331 DOI: 10.1158/1535-7163.mct-15-0923] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 08/25/2016] [Accepted: 09/09/2016] [Indexed: 11/16/2022]
Abstract
Ibrutinib is a potent, small-molecule Bruton tyrosine kinase (BTK) inhibitor developed for the treatment of B-cell malignancies. Ibrutinib covalently binds to Cys481 in the ATP-binding domain of BTK. This cysteine residue is conserved among 9 other tyrosine kinases, including HER2 and EGFR, which can be targeted. Screening large panels of cell lines demonstrated that ibrutinib was growth inhibitory against some solid tumor cells, including those inhibited by other HER2/EGFR inhibitors. Among sensitive cell lines, breast cancer lines with HER2 overexpression were most potently inhibited by ibrutinib (<100 nmol/L); in addition, the IC50s were lower than that of lapatinib and dacomitinib. Inhibition of cell growth by ibrutinib coincided with downregulation of phosphorylation on HER2 and EGFR and their downstream targets, AKT and ERK. Irreversible inhibition of HER2 and EGFR in breast cancer cells was established after 30-minute incubation above 100 nmol/L or following 2-hour incubation at lower concentrations. Furthermore, ibrutinib inhibited recombinant HER2 and EGFR activity that was resistant to dialysis and rapid dilution, suggesting an irreversible interaction. The dual activity toward TEC family (BTK and ITK) and ERBB family kinases was unique to ibrutinib, as ERBB inhibitors do not inhibit or covalently bind BTK or ITK. Xenograft studies with HER2+ MDA-MB-453 and BT-474 cells in mice in conjunction with determination of pharmacokinetics demonstrated significant exposure-dependent inhibition of growth and key signaling molecules at levels that are clinically achievable. Ibrutinib's unique dual spectrum of activity against both TEC family and ERBB kinases suggests broader applications of ibrutinib in oncology. Mol Cancer Ther; 15(12); 2835-44. ©2016 AACR.
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Affiliation(s)
- Jun Chen
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Taisei Kinoshita
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Juthamas Sukbuntherng
- Clinical Pharmacology and DMPK Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
| | - Betty Y Chang
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California.
| | - Laurence Elias
- Research Department, Pharmacyclics LLC, an AbbVie Company, Sunnyvale, California
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Huang Y, Hsu J, Sirisawad M, Kuo HP, Chang BY. Abstract 4860: The BTK inhibitor ibrutinib modulates T cell immunity in mouse models and in differentiated human T cells. Immunology 2016. [DOI: 10.1158/1538-7445.am2016-4860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Hsu J, Huang Y, Chen CT, Chen J, Sirisawad M, Chang BY. Abstract 2321: Ibrutinib enhances antitumor activity in solid tumors when combined with checkpoint inhibitors. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-2321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Anti-CTLA-4 antibodies enhance antitumor immunity by activating antigen-specific cytotoxic T lymphocytes and depleting suppressive regulatory T cells (Treg) from the tumor microenvironment. Anti-PD-L1 or anti-PD-1 blocks negative regulators of T-cell activation and response, facilitating immune-mediated antitumor activity. These therapeutic antitumor approaches via immune checkpoint blockade may be enhanced by ibrutinib (ibr), a first-in-class oral inhibitor of Bruton's tyrosine kinase (BTK) and interleukin-2-inducible T-cell kinase (ITK). A previous study suggested ibr may alter the Th1/Th2 T-cell balance by inactivating ITK and potentially enhancing antitumor immune responses in solid tumor models, including those that do not express BTK (Sagiv-Barfi. PNAS. 2015). Here we report the combined effects of ibr and CTLA-4/PD-1/PD-L1 blockade in a panel of established syngeneic solid tumor models.
Methods: Immunocompetent mice with matched genetic background were inoculated subcutaneously in the right front flank with syngeneic tumor cells. Treatment began when mean tumor size reached approximately 70-100 mm3. Tumor growth inhibition (TGI) and tumor growth delay (TGD) were the study endpoints. The mean and the standard error of the mean for each group were calculated at each time point. Statistical analysis of independent sample t-tests and one-way ANOVA were used for comparisons between and among groups. Potential synergistic effects between treatments were analyzed by two-way ANOVA. Tumor and blood samples were collected for immunologic analysis at the tumor site or in peripheral compartments by flow cytometry.
Results: Treatment with ibr alone resulted in ∼15%-50% TGI across various syngeneic subcutaneous mice models, including MBT-2 (bladder cancer), MC38 (colorectal cancer), and Pan02 (pancreatic tumor), where BTK expression is not prevalent in the tumor lines and tumor cells are not sensitive to ibrutinib. Ibr in combination with checkpoint inhibitors demonstrated benefits in both TGI and TGD in the MC38 model. When ibr was combined with anti-CTLA-4 monoclonal antibody, complete regression of established MC38 tumors was observed.
Conclusion: The efficacy observed with ibr treatment alone in solid tumor models lacking BTK expression suggests ibr can lead to immunomodulation by altering the tumor microenvironment. Additionally, synergistic growth suppression was observed when ibr was combined with checkpoint inhibitors. To further understand the mechanism of action associated with combination ibr immunotherapy in syngeneic models, immunophenotypical analyses of tumor tissues are under investigation.
Citation Format: Jeff Hsu, Yujun Huang, Chun-Te Chen, Jun Chen, Mint Sirisawad, Betty Y. Chang. Ibrutinib enhances antitumor activity in solid tumors when combined with checkpoint inhibitors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2321.
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Affiliation(s)
- Jeff Hsu
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Yujun Huang
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Chun-Te Chen
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Jun Chen
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
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Kuo HP, Hsieh S, Schweighofer KJ, Cheung LWK, Apatira M, Sirisawad M, Wu S, Eckert K, Liang Y, Hsu J, Chen CT, Beaupre D, Chang BY. Abstract 3072: Combination of ibrutinib and corticosteroids in B-cell non-Hodgkin lymphomas (NHL). Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-3072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: The B-cell receptor (BCR) signaling pathway is a major driver in the pathogenesis of B-cell malignancies. A vast array of BCR-associated kinases have emerged as rational therapeutic targets, including Bruton's tyrosine kinase (BTK), which plays a pivotal role in BCR signaling. Ibrutinib is a first-in-class, oral, covalent BTK inhibitor approved in the US for patients with mantle cell lymphoma and chronic lymphocytic leukemia (CLL) who have received at least 1 prior therapy, CLL patients with 17p deletion, and patients with Waldenström's macroglobulinemia. While ibrutinib is efficacious as a single agent, combinations with other drugs may further enhance efficacy and increase response rates in patients with NHLs. Corticosteroids are included in nearly all combination regimens for NHL treatment, showing promising results when combined with chemotherapy and antibodies (Cunningham, Lancet 2013). We therefore evaluated corticosteroids in combination with ibrutinib in preclinical models of activated B cell-like (ABC) and germinal center B cell-like (GCB) diffuse large B-cell lymphoma (DLBCL), and follicular lymphoma (FL).
Methods: ABC-DLBCL, GCB-DLBCL, and FL cell lines were used in this study. Drug effect on cell growth was evaluated with CellTiter-Glo luminescent cell viability assay (Promega) following treatment with ibrutinib or the combinations for 3 days. Combination index (CI) was determined using CalcuSyn. Synergy score (SS) was calculated using the Chalice Analyzer (Horizon CombinatoRx). Mutation profiles were extracted from the Catalogue of Somatic Mutations in Cancer database.
Results: Synergistic growth suppression of dexamethasone and ibrutinib was identified in 7 of 14 GCB-DLBCL cell lines. Dexamethasone had a stronger effect on cells with lower EC50 on ibrutinib treatment. Intriguingly, 4 of these 7 cell lines that showed synergy of the 2 compounds had BCL-2 nonsynonymous mutations, whereas only 1 of the cell lines with no combination effect had BCL-2 silent mutation. In addition to dexamethasone, other corticosteroids, including hydrocortisone, prednisolone, and mometasone, also showed synergy with ibrutinib in GCB-DLBCL (SU-DHL-4, CI = 0.219-0.668, SS = 5.08-15.15; SU-DHL-10, CI = 0.008-0.224, SS = 7.27-11.24), ABC-DLBCL (TMD-8, CI = 0.001-0.016, SS = 21.1), and FL cell lines (DoHH2, CI = 0.020-0.467, SS = 12.3-30.86; WSU-FSCCL, CI = 0.017-0.022, SS = 18.24). The in vivo effect and underlying mechanisms of the combinations are currently under investigation.
Conclusions: We identified synergistic inhibitory effects of ibrutinib and corticosteroids on ABC-DLBCL, GCB-DLBCL, and FL cell growth, providing a rationale for the design of combination clinical trials in these NHL types. Further understanding of the mechanisms contributing to the synergy may help to stratify patient populations and expand treatment to other lymphoid neoplasms.
Citation Format: Hsu-Ping Kuo, Sidney Hsieh, Karl J. Schweighofer, Leo WK Cheung, Mutiah Apatira, Mint Sirisawad, Shiquan Wu, Karl Eckert, Yu Liang, Jeff Hsu, Chun-Te Chen, Darrin Beaupre, Betty Y. Chang. Combination of ibrutinib and corticosteroids in B-cell non-Hodgkin lymphomas (NHL). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3072.
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Affiliation(s)
- Hsu-Ping Kuo
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Sidney Hsieh
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | | | | | | | | | - Shiquan Wu
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Karl Eckert
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Yu Liang
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Jeff Hsu
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Chun-Te Chen
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
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Gunderson AJ, Kaneda MM, Tsujikawa T, Nguyen AV, Affara NI, Ruffell B, Gorjestani S, Liudahl SM, Truitt M, Olson P, Kim G, Hanahan D, Tempero MA, Sheppard B, Irving B, Chang BY, Varner JA, Coussens LM. Bruton Tyrosine Kinase-Dependent Immune Cell Cross-talk Drives Pancreas Cancer. Cancer Discov 2015; 6:270-85. [PMID: 26715645 DOI: 10.1158/2159-8290.cd-15-0827] [Citation(s) in RCA: 361] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 12/22/2015] [Indexed: 11/16/2022]
Abstract
UNLABELLED Pancreas ductal adenocarcinoma (PDAC) has one of the worst 5-year survival rates of all solid tumors, and thus new treatment strategies are urgently needed. Here, we report that targeting Bruton tyrosine kinase (BTK), a key B-cell and macrophage kinase, restores T cell-dependent antitumor immune responses, thereby inhibiting PDAC growth and improving responsiveness to standard-of-care chemotherapy. We report that PDAC tumor growth depends on cross-talk between B cells and FcRγ(+) tumor-associated macrophages, resulting in T(H)2-type macrophage programming via BTK activation in a PI3Kγ-dependent manner. Treatment of PDAC-bearing mice with the BTK inhibitor PCI32765 (ibrutinib) or by PI3Kγ inhibition reprogrammed macrophages toward a T(H)1 phenotype that fostered CD8(+) T-cell cytotoxicity, and suppressed PDAC growth, indicating that BTK signaling mediates PDAC immunosuppression. These data indicate that pharmacologic inhibition of BTK in PDAC can reactivate adaptive immune responses, presenting a new therapeutic modality for this devastating tumor type. SIGNIFICANCE We report that BTK regulates B-cell and macrophage-mediated T-cell suppression in pancreas adenocarcinomas. Inhibition of BTK with the FDA-approved inhibitor ibrutinib restores T cell-dependent antitumor immune responses to inhibit PDAC growth and improves responsiveness to chemotherapy, presenting a new therapeutic modality for pancreas cancer.
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Affiliation(s)
- Andrew J Gunderson
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon
| | - Megan M Kaneda
- Moores Cancer Center, University of California, San Diego, La Jolla, California
| | - Takahiro Tsujikawa
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon. Department of Otolaryngology-Head and Neck Surgery, Oregon Health and Science University, Portland, Oregon
| | - Abraham V Nguyen
- Moores Cancer Center, University of California, San Diego, La Jolla, California
| | - Nesrine I Affara
- Department of Pathology, University of California, San Francisco, California
| | - Brian Ruffell
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon
| | - Sara Gorjestani
- Moores Cancer Center, University of California, San Diego, La Jolla, California
| | - Shannon M Liudahl
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon
| | - Morgan Truitt
- Department of Biochemistry and Biophysics, University of California, San Francisco, California
| | - Peter Olson
- Department of Biochemistry and Biophysics, University of California, San Francisco, California
| | - Grace Kim
- Department of Pathology, University of California, San Francisco, California. Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California
| | - Douglas Hanahan
- Swiss Institute for Experimental Cancer Research, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | - Margaret A Tempero
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California. Department of Medicine, University of California, San Francisco, California
| | - Brett Sheppard
- Department of Surgery, Oregon Health and Science University, Portland, Oregon. Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon
| | | | | | - Judith A Varner
- Moores Cancer Center, University of California, San Diego, La Jolla, California. Department of Pathology, University of California, San Diego, La Jolla, California.
| | - Lisa M Coussens
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon. Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon.
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Niemann CU, Herman SEM, Maric I, Gomez-Rodriguez J, Biancotto A, Chang BY, Martyr S, Stetler-Stevenson M, Yuan CM, Calvo KR, Braylan RC, Valdez J, Lee YS, Wong DH, Jones J, Sun C, Marti GE, Farooqui MZH, Wiestner A. Disruption of in vivo Chronic Lymphocytic Leukemia Tumor-Microenvironment Interactions by Ibrutinib--Findings from an Investigator-Initiated Phase II Study. Clin Cancer Res 2015; 22:1572-82. [PMID: 26660519 DOI: 10.1158/1078-0432.ccr-15-1965] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/19/2015] [Indexed: 12/21/2022]
Abstract
PURPOSE 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. EXPERIMENTAL DESIGN 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. RESULTS 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. CONCLUSIONS 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.
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Affiliation(s)
- Carsten U Niemann
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland. Department of Hematology, Rigshospitalet, Copenhagen University Hospital, Denmark
| | - Sarah E M Herman
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Irina Maric
- Department of Laboratory Medicine, Clinical Research Center, NIH, Bethesda, Maryland
| | | | - Angelique Biancotto
- Center for Human Immunology, Autoimmunity and Inflammation, NIH, Bethesda, Maryland
| | | | - Sabrina Martyr
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | | | - Constance M Yuan
- Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland
| | - Katherine R Calvo
- Department of Laboratory Medicine, Clinical Research Center, NIH, Bethesda, Maryland
| | - Raul C Braylan
- Department of Laboratory Medicine, Clinical Research Center, NIH, Bethesda, Maryland
| | - Janet Valdez
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Yuh Shan Lee
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Deanna H Wong
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Jade Jones
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland. Medical Research Scholars Program, NIH, Bethesda, Maryland
| | - Clare Sun
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Gerald E Marti
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Mohammed Z H Farooqui
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Adrian Wiestner
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland.
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Chen J, Hsu J, Huang Y, James DF, Kinoshita T, Chang BY. Abstract B193: Ibrutinib potentiates the effects of mTOR inhibitors and pazopanib in renal cell carcinoma in vitro and in vivo. Mol Cancer Ther 2015. [DOI: 10.1158/1535-7163.targ-15-b193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Ibrutinib is a first-in-class Bruton's tyrosine kinase (BTK) inhibitor approved for treatment of multiple B-cell malignancies that also inhibits EGFR and HER2 activity (Honigberg, 2010; Gao, 2014). Ibrutinib suppressed growth of EGFR-driven NSCLC or HER2-amplified breast cancer cell lines and reduced tumor growth in murine xenograft models demonstrating the potential of anti-tumor activity in solid tumors (Gao, 2014; Elias, 2013). Ibrutinib also modulated host tumor immunity and enhanced PD-L1 Mab activity in solid tumor models from tumor cells insensitive to BTK or HER kinase inhibition (Sagiv-Barfi, 2015). These results suggest the potential of ibrutinib to be clinically active across a variety of tumors via multiple mechanisms of action (MoA). Immunotherapeutic interventions have had varying success in renal cell carcinoma (RCC), the most common type of kidney cancer. In this study, we determined the therapeutic impact of ibrutinib alone and in combination with approved therapies in RCC in vitro and in vivo and further investigated its MoA.
Methods: The effect of drugs on cell proliferation was determined with CellTiter-Glo (Promega), and apoptosis assayed with annexin-V/PI staining. Signaling pathways were evaluated with Western blotting. Single agent and combinations were studied in vivo by subcutaneous implantation of syngeneic Renca or human 786-0 RCC cell lines into mice.
Results: Treating RCC cells with everolimus alone potently inhibited p-S6, a downstream mTOR target, and significantly inhibited proliferation. Pazopanib, a multi-kinase inhibitor, similarly inhibited pAkt. As reported, these inhibitors up-regulated pAkt and/or pErk, two key pro-survival molecules, after 1h and/or 24h treatment. Such compensatory changes to signaling pathways have been suggested to attenuate the anti-tumor activity of these inhibitors (Wang, 2008; Breuleux, 2009; Grabinski, 2012; Soares, 2013). Interestingly, addition of ibrutinib antagonized up-regulation of pAkt and pErk by everolimus or pazopanib, and enhanced their anti-proliferative activities. In contrast, ibrutinib did not enhance everolimus activity in Caki-1 cells where pAkt and pErk were unaffected by the combination. Ibrutinib alone did not or only weakly inhibited RCC proliferation in cell culture despite inhibition of EGF-induced pEGFR. In contrast, pAkt and pErk, were much less affected, suggesting that EGFR is not a primary driver of proliferation in RCC cells. In vivo, ibrutinib alone showed marginal or no anti-tumor activity in Renca or 786-0 mice models. However, ibrutinib significantly reduced tumor burden in combination with sirolimus (p<0.001) or everolimus (p<0.05) in the Renca and 786-0 RCC models, compared to mTOR inhibitor treatments alone.
Conclusion: These results suggest that ibrutinib, a kinase inhibitor with immune modulatory properties, has anti-tumor activity against RCC when combined with mTOR inhibitors or pazopanib with different target spectrums. Although EGFR is not critical for proliferation in these untreated RCC lines, ibrutinib may prevent ErbB kinases from contributing to feedback up-regulation of Akt/Erk pathways by established drugs. These results provide a preclinical rationale for investigation of ibrutinib as a novel agent for RCC through positive interaction with mTOR inhibitors and/or pazopanib.
Citation Format: Jun Chen, Jeff Hsu, Yujun Huang, Danelle F. James, Taisei Kinoshita, Betty Y. Chang. Ibrutinib potentiates the effects of mTOR inhibitors and pazopanib in renal cell carcinoma in vitro and in vivo. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B193.
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Affiliation(s)
- Jun Chen
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Jeff Hsu
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
| | - Yujun Huang
- Pharmacyclics LLC, an AbbVie Company, Sunnyvale, CA
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Poggesi I, Sardu ML, Marostica E, Sukbuntherng J, Chang BY, Jong JD, Trixhe XWD, Vermeulen A, Nicolao GD, O'Brien SM, Byrd JC, Advani RH, James DF, Deraedt W, Beaupre D, Wang M. Abstract B19: Population pharmacokinetic-pharmacodynamic (PKPD) modeling of ibrutinib in patients with B-cell malignancies. Clin Cancer Res 2015. [DOI: 10.1158/1557-3265.hemmal14-b19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Ibrutinib (IBRU) is an oral Bruton's tyrosine kinase (BTK) inhibitor, approved by US FDA for the treatment of chronic lymphocytic leukemia (CLL/SLL) and mantle cell lymphoma (MCL) patients having received at least one prior therapy. A nonlinear mixed-effects population model was developed to describe the PK of IBRU in patients with B-Cell malignancies and to establish the effect of pathophysiological covariates on its PK behavior. The relationship between PK and BTK engagement in peripheral blood mononuclear cells (PBMC) was also explored. IBRU PK data (3477 observations in 245 patients) were available in patients with MCL, CLL/SLL and recurrent B-cell malignancies at dose levels from 1.25 to 12.5 mg/kg and at fixed doses from 420 to 840 mg once daily. An additional phase 2 study in 119 patients with MCL (772 observations) treated at 560 mg once daily was used to validate the PK model. BTK occupancy was assessed (694 observations in 127 patients) in PBMCs using a fluorescent affinity probe. Various models were tested on the data using the first-order conditional estimation method as implemented in NONMEM version 7.1.
A 2-compartment linear model with sequential zero-first order absorption and first order elimination was able to accommodate available PK data, including those of the validation dataset (prediction errors <15%). PK was dose- and time- independent. IBRU was rapidly absorbed, extensively distributed (volume of distribution at steady-state ~ 10,000 L) and cleared (apparent oral clearance ~1000 L/h). Relative bioavailability in the fasting state was about one third lower compared to the fed condition used in the clinical trials. No significant effect of other pathophysiological covariates on the PK was found (including sex, age or indication) except for body weight and coadministration of antacids, which had a marginal effect on the volume of distribution and duration of absorption, respectively. Analysis of PK-BTK engagement suggested that IBRU is a potent inhibitor of the BTK activity and that its interaction with BTK is rapid and durable.
Citation Format: Italo Poggesi, Maria Luisa Sardu, Eleonora Marostica, Juthamas Sukbuntherng, Betty Y. Chang, Jan de Jong, Xavier Woot de Trixhe, An Vermeulen, Giuseppe De Nicolao, Susan Mary O'Brien, John C Byrd, Ranjana H Advani, Danelle Frances James, William Deraedt, Darrin Beaupre, Michael Wang. Population pharmacokinetic-pharmacodynamic (PKPD) modeling of ibrutinib in patients with B-cell malignancies. [abstract]. In: Proceedings of the AACR Special Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(17 Suppl):Abstract nr B19.
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Affiliation(s)
| | | | | | | | | | - Jan de Jong
- 4Janssen Research & Development, LLC, La Jolla, CA,
| | | | - An Vermeulen
- 1Janssen Research & Development, Beerse, Belgium,
| | | | | | | | | | | | | | | | - Michael Wang
- 5The University of Texas MD Anderson Cancer Center, Houston, TX,
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Sullivan L, Fearnley T, Al-Maskari A, El-Hindy N, Kalantzis G, Chang BY. External dacryocystorhinostomy in consultants and fellows - a comparison of the causes of failure. Hippokratia 2015; 19:216-218. [PMID: 27418779 PMCID: PMC4938467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
PURPOSE Failure of primary dacryocystorhinostomy (DCR) often requires revision surgery to inspect the cause of failure and re-establish anatomic patency. This study aims to specifcally compare the anatomical causes of failure noted during revision DCR of primary external DCR (EX-DCR) and compare the difference between consultants and fellows. METHODS A retrospective review of 37 patients who underwent revision of a primary external approach DCR over a 7-year-period in a University Hospital. All primary surgery was performed by either a consultant surgeon or senior oculoplastic fellow. Details of the initial pathology prior to primary DCR and grade of operating surgeon were collected along with perioperative surgical findings. The cause of failure of the initial surgery was classified according to perioperative findings. Failure was classified as either inappropriately sized/located ostium or fibrous/membranous soft tissue obstruction of the newly created ostium. RESULTS The cause of failure of the initial surgery was soft tissue obstruction in 43.3% and an inappropriately sized/located ostium in 56.7%. In those patients whose primary surgery was performed by a consultant, 73.3% were found to have a soft tissue obstruction and 26.7% were found to have an inappropriately sized/ located ostium. In contrast, if initial surgery was performed by a fellow, 22.7% were found to have a soft tissue obstruction and 77.3% an inappropriately sized/ located ostium (p =0.002). CONCLUSIONS Where the primary surgeon has been a trainee there is a trend toward inadequately sized or located ostium being the most likely causative factor in failure of primary EX-DCR. Hippokratia 2015; 19 (3): 216-218.
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Affiliation(s)
- L Sullivan
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
| | - T Fearnley
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
| | - A Al-Maskari
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
| | - N El-Hindy
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
| | - G Kalantzis
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
| | - B Y Chang
- Ophthalmology Department, St James University Hospital, Beckett Street, Leeds, United Kingdom
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Chen J, Chang BY, Elias L. Abstract 4564: Inhibitory effects of the BTK inhibitor, ibrutinib, on Her2 amplified breast cancer growth, cell cycle progression and clonogenicity. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-4564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Ibrutinib is a Btk inhibitor developed for treatment of B cell malignancies. It binds covalently to cys-481 in Btk's kinase domain, which contributes to the drug's selectivity and enables once daily dosing. A homologous kinase domain cysteine is conserved in 9 other inhibitable kinases including those of the ErbB family. Ibrutinib thereby inhibits the in vitro growth of HER2 amplified breast cancer (BrCa) cells at pharmacologically relevant concentrations, and in vivo, in MB-453 xenografts, at dosages that model clinical exposure. To further characterize these effects we determined the effect of ibrutinib on growth, cell cycle progression, apoptosis and clonogenicity and stem cell-like subpopulations following treatment for short durations.
Methods: BT-474 and SK-BR-3 BrCa cells were treated with ibrutinib at various times and concentrations, and culture continued after washing with fresh media. Cell growth was determined by alamar blue assay or direct cell counting. Cell cycle analysis was performed with PI staining and flow cytometry. Apoptosis was quantitated using flow cytometry with annexin-V/PI staining. Clonogenic assays were performed in 6-well plates with crystal violet staining. Putative “stem-like” cells were assessed by quantitating the aldehyde dehydrogenase 1 (ALDH1) population.
Results: After drug washout, persistence of inhibition of ErbB kinase's phosphorylation and down-stream signaling was observed on a time and exposure dependent basis: while substantial washout-resistant inhibition occurred after 15 min treatment with 0.5 µM ibrutinib, over 1 hour was required for irreversibility following 0.1 µM treatment. Growth inhibition was sustained for 6 days following 1 hr exposure to 0.1 - 0.5 µM of ibrutinib. BrCa cells with short exposure were arrested in G1 with decreased S phase 24h later. ErbB kinases' activation and downstream signaling were also inhibited for up to 6 days. Although growth inhibition was largely cytostatic, 17% and 30% for BT-474 cells and SK-BR-3 cells, respectively, were apoptotic after 6 days at 0.5uM. Continuous treatment induced higher proportions of apoptotic cells. One hour washout or continuous treatment with ibrutinib decreased the putative “stem-like” subpopulation in BrCa cells as measured by Aldefluor assay. A short exposure of BrCa cells to ibrutinib also reduced their in vitro clonogenicity.
Conclusions: Brief exposure to the Btk inhibitor, Ibrutinib, causes irreversible inhibition of ErbB kinases with consequent growth inhibition of HER2 amplified lines characterized by impaired cell cycle progression, evidence of apoptosis, and reductions of the Aldefluor population and clonogenicity. The unique combination of inhibitory properties of ibrutinib for both ErbB and TEC family kinases could prove to be advantageous in selected clinical settings.
Citation Format: Jun Chen, Betty Y. Chang, Laurence Elias. Inhibitory effects of the BTK inhibitor, ibrutinib, on Her2 amplified breast cancer growth, cell cycle progression and clonogenicity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4564. doi:10.1158/1538-7445.AM2014-4564
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Affiliation(s)
- Jun Chen
- Pharmacyclics, Inc., Sunnyvale, CA
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Whang JA, Chang BY. Bruton's tyrosine kinase inhibitors for the treatment of rheumatoid arthritis. Drug Discov Today 2014; 19:1200-4. [DOI: 10.1016/j.drudis.2014.03.028] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 03/31/2014] [Indexed: 01/15/2023]
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Woyach JA, Furman RR, Liu TM, Ozer HG, Zapatka M, Ruppert AS, Xue L, Li DHH, Steggerda SM, Versele M, Dave SS, Zhang J, Yilmaz AS, Jaglowski SM, Blum KA, Lozanski A, Lozanski G, James DF, Barrientos JC, Lichter P, Stilgenbauer S, Buggy JJ, Chang BY, Johnson AJ, Byrd JC. Resistance mechanisms for the Bruton's tyrosine kinase inhibitor ibrutinib. N Engl J Med 2014; 370:2286-94. [PMID: 24869598 PMCID: PMC4144824 DOI: 10.1056/nejmoa1400029] [Citation(s) in RCA: 904] [Impact Index Per Article: 90.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Ibrutinib is an irreversible inhibitor of Bruton's tyrosine kinase (BTK) and is effective in chronic lymphocytic leukemia (CLL). Resistance to irreversible kinase inhibitors and resistance associated with BTK inhibition have not been characterized. Although only a small proportion of patients have had a relapse during ibrutinib therapy, an understanding of resistance mechanisms is important. We evaluated patients with relapsed disease to identify mutations that may mediate ibrutinib resistance. METHODS We performed whole-exome sequencing at baseline and the time of relapse on samples from six patients with acquired resistance to ibrutinib therapy. We then performed functional analysis of identified mutations. In addition, we performed Ion Torrent sequencing for identified resistance mutations on samples from nine patients with prolonged lymphocytosis. RESULTS We identified a cysteine-to-serine mutation in BTK at the binding site of ibrutinib in five patients and identified three distinct mutations in PLCγ2 in two patients. Functional analysis showed that the C481S mutation of BTK results in a protein that is only reversibly inhibited by ibrutinib. The R665W and L845F mutations in PLCγ2 are both potentially gain-of-function mutations that lead to autonomous B-cell-receptor activity. These mutations were not found in any of the patients with prolonged lymphocytosis who were taking ibrutinib. CONCLUSIONS Resistance to the irreversible BTK inhibitor ibrutinib often involves mutation of a cysteine residue where ibrutinib binding occurs. This finding, combined with two additional mutations in PLCγ2 that are immediately downstream of BTK, underscores the importance of the B-cell-receptor pathway in the mechanism of action of ibrutinib in CLL. (Funded by the National Cancer Institute and others.).
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MESH Headings
- Adenine/analogs & derivatives
- Agammaglobulinaemia Tyrosine Kinase
- Aged
- Binding Sites/genetics
- Drug Resistance, Neoplasm/genetics
- Exome
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Middle Aged
- Phospholipase C gamma/genetics
- Phospholipase C gamma/metabolism
- Piperidines
- Point Mutation
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/genetics
- Pyrazoles/pharmacology
- Pyrazoles/therapeutic use
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Receptors, Antigen, B-Cell/metabolism
- Recurrence
- Sequence Analysis, DNA
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Affiliation(s)
- Jennifer A Woyach
- From the Division of Hematology, Department of Internal Medicine (J.A.W., T.-M.L., A.S.R., S.M.J., K.A.B., A.L., A.J.J., J.C. Byrd), the Department of Biomedical Informatics (H.G.O., A.S.Y.), and the Department of Pathology (G.L.), Ohio State University, Columbus; the Department of Medicine, Division of Hematology-Oncology, Weill Cornell Medical College, New York (R.R.F.); the Division of Molecular Genetics, German Cancer Research Center, Heidelberg (M.Z., P.L.), and the Department of Internal Medicine III, University of Ulm, Ulm (S.S.) - both in Germany; Pharmacyclics, Sunnyvale, CA (L.X., D.H.-H.L., S.M.S., D.F.J., J.J.B., B.Y.C.); the Duke Cancer Institute, Duke University, Durham, NC (S.S.D., J.Z.); the Division of Hematology-Oncology, Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New Hyde Park, NY (J.C. Barrientos); and Janssen Research and Development, Beerse, Belgium (M.V.)
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Shinohara M, Chang BY, Buggy JJ, Nagai Y, Kodama T, Asahara H, Takayanagi H. The orally available Btk inhibitor ibrutinib (PCI-32765) protects against osteoclast-mediated bone loss. Bone 2014; 60:8-15. [PMID: 24316417 DOI: 10.1016/j.bone.2013.11.025] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/13/2013] [Accepted: 11/23/2013] [Indexed: 12/19/2022]
Abstract
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.
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Affiliation(s)
- Masahiro Shinohara
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8549, Japan; Department of Systems BioMedicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Betty Y Chang
- Pharmacyclics, Inc., Research Department, Sunnyvale, CA 94085-4521, USA
| | - Joseph J Buggy
- Pharmacyclics, Inc., Research Department, Sunnyvale, CA 94085-4521, USA
| | - Yusuke Nagai
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8549, Japan; Department of Immunology, Graduate School of Medicine, The University of Tokyo, Japan; Japan Science and Technology Agency (JST), Explorative Research for Advanced Technology (ERATO) Program, Takayanagi Osteonetwork Project, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tatsuhiko Kodama
- Department of Molecular Biology and Medicine, Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Komaba 4-6-1, Meguro-ku, Tokyo 153-8904, Japan
| | - Hiroshi Asahara
- Department of Systems BioMedicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hiroshi Takayanagi
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8549, Japan; Department of Immunology, Graduate School of Medicine, The University of Tokyo, Japan; Japan Science and Technology Agency (JST), Explorative Research for Advanced Technology (ERATO) Program, Takayanagi Osteonetwork Project, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.
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Wang ML, Rule S, Martin P, Goy A, Auer R, Kahl BS, Jurczak W, Advani RH, Romaguera JE, Williams ME, Barrientos JC, Chmielowska E, Radford J, Stilgenbauer S, Dreyling M, Jedrzejczak WW, Johnson P, Spurgeon SE, Li L, Zhang L, Newberry K, Ou Z, Cheng N, Fang B, McGreivy J, Clow F, Buggy JJ, Chang BY, Beaupre DM, Kunkel LA, Blum KA. Targeting BTK with ibrutinib in relapsed or refractory mantle-cell lymphoma. N Engl J Med 2013; 369:507-16. [PMID: 23782157 PMCID: PMC4513941 DOI: 10.1056/nejmoa1306220] [Citation(s) in RCA: 1223] [Impact Index Per Article: 111.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Bruton's tyrosine kinase (BTK) is a mediator of the B-cell-receptor signaling pathway implicated in the pathogenesis of B-cell cancers. In a phase 1 study, ibrutinib, a BTK inhibitor, showed antitumor activity in several types of non-Hodgkin's lymphoma, including mantle-cell lymphoma. METHODS In this phase 2 study, we investigated oral ibrutinib, at a daily dose of 560 mg, in 111 patients with relapsed or refractory mantle-cell lymphoma. Patients were enrolled into two groups: those who had previously received at least 2 cycles of bortezomib therapy and those who had received less than 2 complete cycles of bortezomib or had received no prior bortezomib therapy. The primary end point was the overall response rate. Secondary end points were duration of response, progression-free survival, overall survival, and safety. RESULTS The median age was 68 years, and 86% of patients had intermediate-risk or high-risk mantle-cell lymphoma according to clinical prognostic factors. Patients had received a median of three prior therapies. The most common treatment-related adverse events were mild or moderate diarrhea, fatigue, and nausea. Grade 3 or higher hematologic events were infrequent and included neutropenia (in 16% of patients), thrombocytopenia (in 11%), and anemia (in 10%). A response rate of 68% (75 patients) was observed, with a complete response rate of 21% and a partial response rate of 47%; prior treatment with bortezomib had no effect on the response rate. With an estimated median follow-up of 15.3 months, the estimated median response duration was 17.5 months (95% confidence interval [CI], 15.8 to not reached), the estimated median progression-free survival was 13.9 months (95% CI, 7.0 to not reached), and the median overall survival was not reached. The estimated rate of overall survival was 58% at 18 months. CONCLUSIONS Ibrutinib shows durable single-agent efficacy in relapsed or refractory mantle-cell lymphoma. (Funded by Pharmacyclics and others; ClinicalTrials.gov number, NCT01236391.)
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Affiliation(s)
- Michael L Wang
- Department of Lymphoma and Myeloma, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
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Byrd JC, Furman RR, Coutre SE, Flinn IW, Burger JA, Blum KA, Grant B, Sharman JP, Coleman M, Wierda WG, Jones JA, Zhao W, Heerema NA, Johnson AJ, Sukbuntherng J, Chang BY, Clow F, Hedrick E, Buggy JJ, James DF, O'Brien S. Targeting BTK with ibrutinib in relapsed chronic lymphocytic leukemia. N Engl J Med 2013; 369:32-42. [PMID: 23782158 PMCID: PMC3772525 DOI: 10.1056/nejmoa1215637] [Citation(s) in RCA: 1745] [Impact Index Per Article: 158.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The treatment of relapsed chronic lymphocytic leukemia (CLL) has resulted in few durable remissions. Bruton's tyrosine kinase (BTK), an essential component of B-cell-receptor signaling, mediates interactions with the tumor microenvironment and promotes the survival and proliferation of CLL cells. METHODS We conducted a phase 1b-2 multicenter study to assess the safety, efficacy, pharmacokinetics, and pharmacodynamics of ibrutinib (PCI-32765), a first-in-class, oral covalent inhibitor of BTK designed for treatment of B-cell cancers, in patients with relapsed or refractory CLL or small lymphocytic lymphoma. A total of 85 patients, the majority of whom were considered to have high-risk disease, received ibrutinib orally once daily; 51 received 420 mg, and 34 received 840 mg. RESULTS Toxic effects were predominantly grade 1 or 2 and included transient diarrhea, fatigue, and upper respiratory tract infection; thus, patients could receive extended treatment with minimal hematologic toxic effects. The overall response rate was the same in the group that received 420 mg and the group that received 840 mg (71%), and an additional 20% and 15% of patients in the respective groups had a partial response with lymphocytosis. The response was independent of clinical and genomic risk factors present before treatment, including advanced-stage disease, the number of previous therapies, and the 17p13.1 deletion. At 26 months, the estimated progression-free survival rate was 75% and the rate of overall survival was 83%. CONCLUSIONS Ibrutinib was associated with a high frequency of durable remissions in patients with relapsed or refractory CLL and small lymphocytic lymphoma, including patients with high-risk genetic lesions. (Funded by Pharmacyclics and others; ClinicalTrials.gov number, NCT01105247.).
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Affiliation(s)
- John C Byrd
- Division of Hematology, Department of Internal Medicine, Ohio State University, Columbus, OH 43210, USA.
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Chang BY, Furman RR, Zapatka M, Barrientos JC, Li D, Steggerda S, Eckert K, Francesco M, Woyach JA, Johnson AJ, James DF, Versele M, Byrd JC, Stilgenbauer S, Buggy JJ. Use of tumor genomic profiling to reveal mechanisms of resistance to the BTK inhibitor ibrutinib in chronic lymphocytic leukemia (CLL). J Clin Oncol 2013. [DOI: 10.1200/jco.2013.31.15_suppl.7014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7014 Background: Ibrutinib interacts covalently with cysteine 481 of Bruton tyrosine kinase (BTK), resulting in targeted inhibition of B cell receptor signaling. Early trials of ibrutinib mono- or combination therapy enrolled 246 CLL patients receiving a median of 14 months of ibrutinib. 20 patients (8%) experienced progressive disease (PD), including 8 patients with Richter's transformation. Here we examine changes to the CLL genome in 3 patients that acquired resistance to ibrutinib. Methods: Ibrutinib resistance was defined as patients achieving partial response (PR) or better lasting ≥ 6 months, then developing PD without Richter’s transformation. RNAseq and whole exome sequencing (WES) followed by comparative genome analysis was performed at baseline and after PD and confirmed by Sanger sequencing. RNAseq and WES data were aligned using TopHat and BWA software. Single nucleotide variations (SNVs) were identified using SAMtools mpileup. Results: Compared to patients who relapsed from conventional chemotherapy, minimal genomic changes were acquired in ibrutinib resistant patients, reflecting relative genomic stability. SNVs were discovered in 3 patients specific to the relapse sample (Table). 2 out of 3 patients had distinct SNVs that each encode a cysteine-to-serine substitution at position 481of BTK (C481S). Homologous cysteine residues in BMX, ITK, TEC and BLK were wild-type (WT). Ibrutinib inhibited recombinant C481S 25 fold less potently than WT, and could not covalently bind C481S expressed in cells. The third patient had WT BTK, but acquired a potential gain-of-function mutation encoding a R665W substitution in PLCg2, a substrate of BTK, consistent with constitutive PLCg2 activation. Conclusions: Although rare, the acquisition of C481S BTK and R665W PLCg2 mutations in the setting of resistance confirms BTK as an important pharmacologic target of ibrutinib, and suggests mechanisms of ibrutinib resistance. [Table: see text]
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Affiliation(s)
| | | | - Marc Zapatka
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | | | | | | | | | | | - Amy J Johnson
- The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH
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Dubovsky JA, Beckwith KA, Natarajan G, Woyach JA, Jaglowski S, Hessler J, Liu TM, Chang BY, Larkin KM, Stefanovski MR, Frissora FW, Smith LL, Smucker KA, Flynn JM, Jones JA, Andritsos LA, Maddocks K, Lehman AM, Furman R, Sharman J, Mishra A, Caligiuri MA, Satoskar AR, Buggy JJ, Muthusamy N, Johnson AJ, Byrd JC. Abstract 492: Ibrutinib inhibits Interleukin-2 inducible kinase, driving a Th1 selective pressure in human leukemia patients that serves to alleviate tumor-induced immunosupression. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Interleukin-2 Inducible Kinase (ITK) is an appealing therapeutic target given its critical role in polarizing T-cell immunity against various infectious, autoimmune, and neoplastic diseases. ITK activity promotes Th2 immunity, thereby subverting healthy Th1-based immune surveillance. Th2 CD4 T-cells depend on ITK for activation, whereas Th1 and CD8 T-cells have compensatory resting lymphocyte kinase (RLK) that conducts T-cell receptor activation in the absence of ITK. Similar to many other tumors, chronic lymphocytic leukemia (CLL) directs an aberrant Th2 bias that drives immune evasion, promotes a supportive microenvironment, and cripples adaptive immunity. In CLL, this immune suppression leads to severe infections which are a leading cause of death. Although ITK inhibitors have the promise of alleviating tumor-induced immune suppression, to date no clinically viable ITK inhibitor exists. Ibrutinib is an irreversible inhibitor of Bruton's tyrosine kinase (BTK) with outstanding activity and tolerability in B-cell malignancies. The striking homology between BTK and ITK combined with our in silico docking studies and in vitro kinase inhibition profiles led us to identify ibrutinib as the first clinically viable irreversible ITK inhibitor. We further confirmed both molecular and functional outcomes using Jurkat T-cells and in vitro polarized Th1 and Th2 CD4 T-cells. We found that mutation of the ITK-Cys442 covalent binding residue for ibrutinib alleviated molecular inhibition. We also demonstrated that Th1 and CD8 T-cell restricted expression of RLK provides a compensatory platform for T-cell activation, offering a molecular explanation for the selective outgrowth of cytotoxic Th1-biased immunity. This effect was confirmed using T-cells directly derived from CLL patients. To clearly demonstrate this effect in vivo, we utilized the Leishmania major model of Th2-mediated infection. Ibrutinib enhanced resistance to the parasite by eliciting robust Th1 immunity. To demonstrate a direct clinical relevance in the setting of CLL we utilized a novel listeriosis/leukemia mouse model. In this model, we observed complete recovery of functional immunity, with all ibrutinib-treated mice surviving a potentially lethal Listeria monocytogenes infection. We further confirmed irreversible binding of ITK in patients currently receiving ibrutinib as part of a clinical trial. Finally, we found that ibrutinib inhibited phosphorlyation of ITK's direct downstream target PLCγ1 in CD4 T-cells. Together, our results provide novel molecular insights into the mechanism of action of ibrutinib in the context of Th2-biased immunosuppressive leukemia. We also postulate that ibrutinib's irreversible ITK inhibitory effects may prove beneficial in a number of other autoimmune, inflammatory, parasitic, and viral diseases.
Citation Format: Jason A. Dubovsky, Kyle A. Beckwith, Gayathri Natarajan, Jennifer A. Woyach, Samantha Jaglowski, Joshua Hessler, Ta-Ming Liu, Betty Y. Chang, Karilyn M. Larkin, Matthew R. Stefanovski, Frank W. Frissora, Lisa L. Smith, Kelly A. Smucker, Joseph M. Flynn, Jeffrey A. Jones, Leslie A. Andritsos, Kami Maddocks, Amy M. Lehman, Richard Furman, Jeff Sharman, Anjali Mishra, Michael A. Caligiuri, Abhay R. Satoskar, Joseph J. Buggy, Natarajan Muthusamy, Amy J. Johnson, John C. Byrd. Ibrutinib inhibits Interleukin-2 inducible kinase, driving a Th1 selective pressure in human leukemia patients that serves to alleviate tumor-induced immunosupression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 492. doi:10.1158/1538-7445.AM2013-492
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Jeff Sharman
- 4Willamette Valley Cancer Institute, Springfield, OR
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Advani RH, Buggy JJ, Sharman JP, Smith SM, Boyd TE, Grant B, Kolibaba KS, Furman RR, Rodriguez S, Chang BY, Sukbuntherng J, Izumi R, Hamdy A, Hedrick E, Fowler NH. Bruton tyrosine kinase inhibitor ibrutinib (PCI-32765) has significant activity in patients with relapsed/refractory B-cell malignancies. J Clin Oncol 2012; 31:88-94. [PMID: 23045577 DOI: 10.1200/jco.2012.42.7906] [Citation(s) in RCA: 845] [Impact Index Per Article: 70.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Survival and progression of mature B-cell malignancies depend on signals from the B-cell antigen receptor, and Bruton tyrosine kinase (BTK) is a critical signaling kinase in this pathway. We evaluated ibrutinib (PCI-32765), a small-molecule irreversible inhibitor of BTK, in patients with B-cell malignancies. PATIENTS AND METHODS Patients with relapsed or refractory B-cell lymphoma and chronic lymphocytic leukemia received escalating oral doses of ibrutinib. Two schedules were evaluated: one, 28 days on, 7 days off; and two, once-daily continuous dosing. Occupancy of BTK by ibrutinib in peripheral blood was monitored using a fluorescent affinity probe. Dose escalation proceeded until either the maximum-tolerated dose (MTD) was achieved or, in the absence of MTD, until three dose levels above full BTK occupancy by ibrutinib. Response was evaluated every two cycles. RESULTS Fifty-six patients with a variety of B-cell malignancies were treated over seven cohorts. Most adverse events were grade 1 and 2 in severity and self-limited. Dose-limiting events were not observed, even with prolonged dosing. Full occupancy of the BTK active site occurred at 2.5 mg/kg per day, and dose escalation continued to 12.5 mg/kg per day without reaching MTD. Pharmacokinetic data indicated rapid absorption and elimination, yet BTK occupancy was maintained for at least 24 hours, consistent with the irreversible mechanism. Objective response rate in 50 evaluable patients was 60%, including complete response of 16%. Median progression-free survival in all patients was 13.6 months. CONCLUSION Ibrutinib, a novel BTK-targeting inhibitor, is well tolerated, with substantial activity across B-cell histologies.
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Affiliation(s)
- Ranjana H Advani
- Stanford University Medical Center, Stanford, CA 94305-5821, USA.
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Chang BY, Huang MM, Francesco M, Chen J, Sokolove J, Magadala P, Robinson WH, Buggy JJ. The Bruton tyrosine kinase inhibitor PCI-32765 ameliorates autoimmune arthritis by inhibition of multiple effector cells. Arthritis Res Ther 2011; 13:R115. [PMID: 21752263 PMCID: PMC3239353 DOI: 10.1186/ar3400] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2011] [Revised: 06/01/2011] [Accepted: 07/13/2011] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION The aim was to determine the effect of the Bruton tyrosine kinase (Btk)-selective inhibitor PCI-32765, currently in Phase I/II studies in lymphoma trials, in arthritis and immune-complex (IC) based animal models and describe the underlying cellular mechanisms. METHODS PCI-32765 was administered in a series of murine IC disease models including collagen-induced arthritis (CIA), collagen antibody-induced arthritis (CAIA), reversed passive anaphylactic reaction (RPA), and passive cutaneous anaphylaxis (PCA). Clinical and pathologic features characteristic of each model were examined following treatment. PCI-32765 was then examined in assays using immune cells relevant to the pathogenesis of arthritis, and where Btk is thought to play a functional role. These included proliferation and calcium mobilization in B cells, cytokine and chemokine production in monocytes/macrophages, degranulation of mast cells and its subsequent cytokine/chemokine production. RESULTS PCI-32765 dose-dependently and potently reversed arthritic inflammation in a therapeutic CIA model with an ED(50) of 2.6 mg/kg/day. PCI-32765 also prevented clinical arthritis in CAIA models. In both models, infiltration of monocytes and macrophages into the synovium was completely inhibited and importantly, the bone and cartilage integrity of the joints were preserved. PCI-32765 reduced inflammation in the Arthus and PCA assays. In vitro, PCI-32765 inhibited BCR-activated primary B cell proliferation (IC(50) = 8 nM). Following FcγR stimulation, PCI-32765 inhibited TNFα, IL-1β and IL-6 production in primary monocytes (IC(50) = 2.6, 0.5, 3.9 nM, respectively). Following FcεRI stimulation of cultured human mast cells, PCI-32765 inhibited release of histamine, PGD(2), TNF-α, IL-8 and MCP-1. CONCLUSIONS PCI-32765 is efficacious in CIA, and in IC models that do not depend upon autoantibody production from B cells. Thus PCI-32765 targets not only B lymphocytes but also monocytes, macrophages and mast cells, which are important Btk-expressing effector cells in arthritis.
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Affiliation(s)
- Betty Y Chang
- Pharmacyclics, Inc, Research Department, Sunnyvale, CA 94085-4521, USA.
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Chang BY, Zhao F, He X, Ren H, Braselmann S, Taylor V, Wicks J, Payan DG, Grossbard EB, Pine PR, Bullard DC. JAK3 inhibition significantly attenuates psoriasiform skin inflammation in CD18 mutant PL/J mice. J Immunol 2009; 183:2183-92. [PMID: 19596999 DOI: 10.4049/jimmunol.0804063] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
JAK3, a member of the Janus kinase family, is predominantly expressed in hemopoietic cells and binds specifically to the common gamma chain of a subfamily of cytokine receptors that includes IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21. Previous studies suggest that this tyrosine kinase plays key roles in mediating T cell functions, and inhibition of JAK3 has been shown to prevent graft rejection and decrease the severity of arthritis in rodent models. However, the functions of JAK3 in the development of skin immune responses and diseases such as psoriasis have not been determined. CD18 mutant PL/J mice develop spontaneous T cell-dependent psoriasiform skin disease with several similarities to human psoriasis. In this study, we treated mice with established skin disease with R348, a small molecule inhibitor of JAK3, and observed a marked attenuation of skin lesions following 6 wk of treatment. Histological analyses revealed major reductions of both epidermal and dermal lesion severity scores in R348-treated CD18-deficient PL/J mice compared with vehicle controls, which was associated with decreased CD4(+) T cell infiltration. In addition, systemic levels of IL-17, IL-22, IL-23, and TNF-alpha were significantly lower in mice receiving the compound, and T cells isolated from R348-treated mice also showed reduced phosphorylation of Stat5 after stimulation with IL-2. These findings suggest that small-molecule inhibitors of JAK3 may be useful in the treatment of inflammatory skin diseases such as psoriasis and strongly implicate JAK signaling events as important in the pathogenesis of this disease.
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Affiliation(s)
- Betty Y Chang
- Rigel Pharmaceuticals, Inc, South San Francisco, CA 94080, USA.
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Zhang LY, Chang BY, Dong T, He PL, Yang WJ, Wang ZY. Simultaneous determination of salbutamol, ractopamine, and clenbuterol in animal feeds by SPE and LC-MS. J Chromatogr Sci 2009; 47:324-8. [PMID: 19406021 DOI: 10.1093/chromsci/47.4.324] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
A liquid chromatography-mass spectrometry (LC-MS) method for the simultaneous determination of salbutamol, ractopamine, and clenbuterol in commercial feeds was developed. Samples were extracted with phosphoric acid-methanol solution, and further clean-up was achieved with a C18 cation exchange mixed mode cartridge. Separation of analytes was developed on a C18 column with 0.01 M aqueous ammonium formate solution (pH 3.8)-acetonitrile by gradient program, and characterized by LC-MS on a quadrupole detector, in electrospray positive ion mode. This method provides average recoveries for salbutamol, ractopamine, and clenbuterol of 83-110% and coefficients of variation of 1.5-11% in feeds spiked in the range of 0.5-500 mg/kg. The limits of detection and quantification in feeds were 0.01 mg/kg and 0.05 mg/kg, respectively. Such limits are well below the dose of 2-25 mg/kg feed proposed as effective.
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Affiliation(s)
- L Y Zhang
- State Key Laboratory on Animal Nutrition, China Agricultural University, Beijing, PR China, 100094.
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Norris JH, Gale RP, Nkumbe H, Backhouse OC, Bernadin P, Chang BY. Oculoplastic surgery in Madagascar: a review. Community Eye Health 2009; 22:S3-4. [PMID: 19888361 PMCID: PMC2767128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- JH Norris
- St James's University Hospital, Leeds, UK
| | - RP Gale
- York District Hospital, York, UK
| | - H Nkumbe
- Andranmadio Hospital, Antsirabe, Madagascar
| | | | - P Bernadin
- HJRA Government Hospital, Antananarivo, Madagascar
| | - BY Chang
- St James's University Hospital, Leeds, UK
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Mamidipudi V, Chang BY, Harte RA, Lee KC, Cartwright CA. RACK1 inhibits the serum- and anchorage-independent growth of v-Src transformed cells. FEBS Lett 2004; 567:321-6. [PMID: 15178345 DOI: 10.1016/j.febslet.2004.03.125] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2004] [Revised: 02/23/2004] [Accepted: 03/26/2004] [Indexed: 11/19/2022]
Abstract
Cancer cells are capable of serum- and anchorage-independent growth, and focus formation on monolayers of normal cells. Previously, we showed that RACK1 inhibits c-Src kinase activity and NIH3T3 cell growth. Here, we show that RACK1 partially inhibits v-Src kinase activity, and the serum- and anchorage-independent growth of v-Src transformed cells, but has no effect on focus formation. RACK1-overexpressing v-Src cells show disassembly of podosomes, which are actin-rich structures that are distinctive to fully transformed cells. Together, our results demonstrate that RACK1 overexpression in v-Src cells partially reverses the transformed phenotype of the cells. Our results identify an endogenous inhibitor of the oncogenic Src tyrosine kinase and of cell transformation.
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Affiliation(s)
- Vidya Mamidipudi
- Department of Medicine, Stanford University, Stanford, CA 94305, USA
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Chang BY, Cartwright CA. Detection of protein kinase-binding partners by the yeast two-hybrid analysis. Methods Mol Biol 2004; 233:327-43. [PMID: 12840519 DOI: 10.1385/1-59259-397-6:327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Affiliation(s)
- Betty Y Chang
- Department of Medicine, Stanford University School of Medicine, CA, USA
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Chang BY, Peavy TR, Wardrip NJ, Hedrick JL. The Xenopus laevis cortical granule lectin: cDNA cloning, developmental expression, and identification of the eglectin family of lectins. Comp Biochem Physiol A Mol Integr Physiol 2004; 137:115-29. [PMID: 14720597 DOI: 10.1016/s1095-6433(03)00269-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A Xenopus laevis egg cortical granule, calcium-dependent, galactosyl-specific lectin participates in forming the fertilization layer of the egg envelope and functions in establishing a block to polyspermy. We report the cDNA cloning of the lectin, expression of the cortical granule lectin gene during oogenesis and early development, and identification of a new family of lectins. The translated cDNA for the cortical granule lectin had a signal peptide, a structural sequence of 298 amino acids, a molecular weight of 32.7 K, contained consensus sequence sites for N-glycosylation and a fibrinogen domain. The lectin cDNA was expressed during early stages of oogenesis. Lectin glycoprotein levels were constant during development with 2/3 of the lectin associated with the extracellular perivitelline space and the egg/embryo fertilization envelope. Lectin mRNA levels were from 100- to 1000-fold greater in ovary than in other adult tissues. The lectin had no sequence homology to the previously identified lectin families. The lectin had 41-88% amino acid identity with nine translated cDNA sequences from an ascidian, lamprey, frog, mouse, and human. Based on the conserved carbohydrate binding and structural properties of these glycoproteins, we propose a new family of lectins, the eglectin family.
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Affiliation(s)
- Betty Y Chang
- Section of Molecular and Cellular Biology, University of California, One Shields Avenue, Davis, CA 95616, USA
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Chen HL, Li DF, Chang BY, Gong LM, Piao XS, Yi GF, Zhang JX. Effects of lentinan on broiler splenocyte proliferation, interleukin-2 production, and signal transduction. Poult Sci 2003; 82:760-6. [PMID: 12762398 DOI: 10.1093/ps/82.5.760] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Lentinan (LEN) is an intensively studied beta-glucan that has been shown to have immunostimulating and antitumor functions. However, it currently is not used in veterinary practice and animal production. This study was conducted to investigate the impacts of LEN on broiler splenocyte proliferation, interleukin-2 (IL-2) production, and to explore its effects on receptor signal transduction by determining signaling molecules, including nitric oxide (NO), cytosolic-free Ca2+, cytosolic cyclic adenosine monophosphate (cAMP), and cyclic guanosine monophosphate (cGMP). The results showed that compared to the control all three measured doses, including 40, 80, and 160 microg/mL LEN, increased splenocyte proliferation and IL-2 production (P < 0.05). Lentinan increased splenocyte NO production and cytosolic-free calcium concentration in a dose-dependent manner (P < 0.001). After incubating splenocytes for 20 min, LEN increased intracellular cAMP and cGMP concentrations at a dose of 80 and 160 microg/mL, respectively. However, after incubating the splenocytes for 60 min, LEN had no effect on cytosolic cAMP and cGMP concentration irrespective of the LEN dosage. Those results indicated that LEN had immunostimulatory effects on splenocytes by increasing splenocyte proliferation and IL-2 production and by activating splenocyte receptor signal transduction.
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Affiliation(s)
- H L Chen
- China Agricultural University, National Feed Engineer and Technology Center, Beijing, China,100094
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Chen HL, Li DF, Chang BY, Gong LM, Dai JG, Yi GF. Effects of Chinese herbal polysaccharides on the immunity and growth performance of young broilers. Poult Sci 2003; 82:364-70. [PMID: 12705395 DOI: 10.1093/ps/82.3.364] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Two trials were conducted to study the effects of two Chinese herbal polysaccharides [achyranthan (ACH), a low-molecular-weight polysaccharide, and astragalan (APS), a high-molecular-weight polysaccaride] on the immunity and growth performance of young broilers. Trial 1 was a 28-d growth assay, in which 7-d-old broilers (n = 240) were randomly allotted to one of three dietary treatments, with eight replicate pens per treatment and ten chickens per pen. Dietary treatments included a control corn-soy-fishmeal (Treatment 1), a diet with 200 mg/kg APS (Treatment 2), and a diet with 200 mg/kg ACH (Treatment 3). Blood samples were collected by cardiac puncture on Days 7, 14, 21, and 28 for determination of serum parameters, and chickens were killed on Day 28 to measure immune organ indexes. Trial 2 was an in vitro trial to study the effects of different concentrations of polysaccharides on broiler splenocyte functions. In Trial 1, feeding either APS or ACH had no significant effects on growth performance of broilers relative to the control. However, compared to the control, feeding ACH significantly increased microhemagglutination inhibition (HI) antibody titers, bursa of Fabricius index, serum albumin, serum calcium, and nitric oxide (NO) concentrations at Day 28 (P < or = 0.05). In Trial 2, both polysaccharides showed significant immunostimulating effects. They increased NO and interleukin-2 (IL-2) production of splenocytes and enhanced splenocyte proliferation in a dose-dependent manner (P < 0.05). Those results indicate that the immunostimulating effects of APS are not as pronounced as those of ACH. Achyranthan showed immunostimulating effects in both the growth assay and in vitro studies. Therefore, ACH may be a Chinese herbal polysaccharide that has the potential to be used as a feed additive to improve broilers' immunity.
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Affiliation(s)
- H L Chen
- Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China
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Chang BY, Harte RA, Cartwright CA. RACK1: a novel substrate for the Src protein-tyrosine kinase. Oncogene 2002; 21:7619-29. [PMID: 12400005 DOI: 10.1038/sj.onc.1206002] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2002] [Revised: 08/20/2002] [Accepted: 08/29/2002] [Indexed: 12/30/2022]
Abstract
RACK1 is one of a group of PKC-interacting proteins collectively called RACKs (Receptors for Activated C-Kinases). Previously, we showed that RACK1 also interacts with the Src tyrosine kinase, and is an inhibitor of Src activity and cell growth. PKC activation induces the intracellular movement and co-localization of RACK1 and Src, and the tyrosine phosphorylation of RACK1. To determine whether RACK1 is a Src substrate, we assessed phosphorylation of RACK1 by various tyrosine kinases in vitro, and by kinase-active and inactive mutants of Src in vivo. We found that RACK1 is a Src substrate. Moreover, Src activity is necessary for both the tyrosine phosphorylation of RACK1 and the binding of RACK1 to Src's SH2 domain that occur following PKC activation. To identify the tyrosine(s) on RACK1 that is phosphorylated by Src, we generated and tested a series of RACK1 mutants. We found that Src phosphorylates RACK1 on Tyr 228 and/or Tyr 246, highly-conserved tyrosines located in the sixth WD repeat that interact with Src's SH2 domain. We think that RACK1 is an important Src substrate that signals downstream of growth factor receptor tyrosine kinases and is involved in the regulation of Src function and cell growth.
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Affiliation(s)
- Betty Y Chang
- Department of Medicine, Stanford University, Stanford, California, CA 94305, USA
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Chang BY, Chiang M, Cartwright CA. The interaction of Src and RACK1 is enhanced by activation of protein kinase C and tyrosine phosphorylation of RACK1. J Biol Chem 2001; 276:20346-56. [PMID: 11279199 DOI: 10.1074/jbc.m101375200] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RACK1 is an intracellular receptor for the serine/ threonine protein kinase C. Previously, we demonstrated that RACK1 also interacts with the Src protein-tyrosine kinase. RACK1, via its association with these protein kinases, may play a key role in signal transduction. To further characterize the Src-RACK1 interaction and to analyze mechanisms by which cross-talk occurs between the two RACK1-linked signaling kinases, we identified sites on Src and RACK1 that mediate their binding, and factors that regulate their interaction. We found that the interaction of Src and RACK1 is mediated, in part, by the SH2 domain of Src and by phosphotyrosines in the sixth WD repeat of RACK1, and is enhanced by serum or platelet-derived growth factor stimulation, protein kinase C activation, and tyrosine phosphorylation of RACK1. To the best of our knowledge, this is the first report of tyrosine phosphorylation of a member of the WD repeat family of proteins. We think that tyrosine phosphorylation of these proteins is an important mechanism of signal transduction in cells.
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Affiliation(s)
- B Y Chang
- Department of Medicine, Stanford University, Stanford, California 94305, USA
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Liou DY, Hsu YH, Wung CH, Wang WH, Lin NS, Chang BY. Functional analyses and identification of two arginine residues essential to the ATP-utilizing activity of the triple gene block protein 1 of bamboo mosaic potexvirus. Virology 2000; 277:336-44. [PMID: 11080481 DOI: 10.1006/viro.2000.0610] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The TGBp1 of bamboo mosaic potexvirus (BaMV) is encoded by the first overlapping gene of the triple-gene-block (TGB), whose products are thought to play roles in virus movement between plant cells. This protein forms cytoplasmic inclusions associated with virus particles in the BaMV-infected tissues. It has been proposed that the inclusion is one of the active forms of TGBp1. To prove this idea, we purified the TGBp1 inclusions from both the BaMV-infected Chenopodium quinoa and Escherichia coli cells overexpressing this protein to test some of their biochemical activities. We found that the TGBp1 inclusions isolated from the infected plant leaves, but not from E. coli, possess the NTP-binding and NTPase activities. However, they lack the RNA-binding activity possessed by the soluble TGBp1. These results indicate that the TGBp1 proteins in the BaMV-infected tissues assume two different functional forms. Mutational analyses and competition experiments show that the two arginine residues, Arg-16 and Arg-21, essential to RNA binding, are also required for the ATP-utilizing activity of the soluble TGBp1. This indicates that a same-structure motif is required for the two functions of the soluble TGBp1. The location of the two arginine residues outside the seven conserved motifs of the NTP-utilizing superfamily I RNA helicases, to which TGBp1 belongs, suggests that an extra-structure motif, besides the seven conserved ones, is required for the NTP-utilizing activity of the TGBp1 protein of BaMV.
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Affiliation(s)
- D Y Liou
- Institute of Biochemistry, National Chung-Hsing University, Taichung, Taiwan, Republic of China
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Sola IR, Chang BY, Santamaria J, Malinovsky VS, Krause JL. Selective excitation of vibrational states by shaping of light-induced potentials. Phys Rev Lett 2000; 85:4241-4244. [PMID: 11060608 DOI: 10.1103/physrevlett.85.4241] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2000] [Indexed: 05/23/2023]
Abstract
In this Letter we describe a method for population transfer using intense, ultrafast laser pulses. The selectivity is accomplished by careful shaping of light-induced potentials (LIPs). Creation and control of the LIPs is accomplished by choosing pairs of pulses with proper frequency detunings and time delays. As an example, selective population transfer is demonstrated for a three-state model of the sodium dimer.
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Affiliation(s)
- IR Sola
- Departamento de Quimica Fisica I, Universidad Complutense, 28040 Madrid, Spain
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Abstract
AIM To compare pulsatile ocular blood flow (POBF) and intraocular pressure (IOP) between eyes of patients receiving either peribulbar (with and without balloon compression) or subconjunctival local anaesthesia (LA). METHODS 30 eyes of 30 patients undergoing cataract surgery by phacoemulsification were investigated in a study of parallel group design. Ten patients had peribulbar LA and 10 minutes compression with a Honan's balloon (group A). A further 10 patients who received peribulbar LA alone (group B) acted as controls for the effects of balloon compression. Ten other patients were given subconjunctival LA (group C). POBF and IOP were measured using a modified Langham pneumatonometer. Three measurements were made in each eye, the first recording immediately before LA, the second 1 minute after, and the third 10 minutes after LA. RESULTS No significant change in POBF or IOP was recorded in eyes receiving subconjunctival LA. In the peribulbar groups (A and B), there was a drop in median POBF of 252 and 138 microl/min respectively 1 minute after LA, which was statistically significant in both groups (p<0. 01). By 10 minutes, POBF tended to return to baseline levels, but remained significantly reduced in group B (p<0.05). In addition, there was a significant (p<0.05) reduction in IOP (mean drop of 4.82 mm Hg) in group A following peribulbar LA with balloon compression. CONCLUSIONS POBF was significantly reduced after peribulbar LA but was unchanged after subconjunctival LA. Balloon compression reduced IOP and improved POBF following peribulbar LA. The findings may have clinical implications in patients with compromised ocular circulation or significant glaucomatous optic neuropathy.
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Affiliation(s)
- B Y Chang
- West of England Eye Unit, Royal Devon and Exeter Hospital, Exeter, UK
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Abstract
Bacillus subtilis DB1005 is a temperature-sensitive (Ts) sigA mutant containing double-amino-acid substitutions (I198A and I202A) on the hydrophobic face of the promoter -10 binding helix of sigma(A) factor. We have analyzed the structural and functional properties of this mutant sigma(A) factor both in vivo and in vitro. Our data revealed that the Ts sigma(A) factor possessed predominantly a multimeric structure which was prone to aggregation at restrictive temperature. The extensive aggregation of the Ts sigma(A) resulted in a very low core-binding activity of the Ts sigma(A) factor and a markedly reduced sigma(A)-RNA polymerase activity in B. subtilis DB1005, suggesting that extensive aggregation of the Ts sigma(A) is the main trigger for the temperature sensitivity of B. subtilis DB1005. Partial proteolysis, tryptophan fluorescence and 1-anilinonaphthalene-8-sulfonate-binding analyses revealed that the hydrophobic face of the promoter -10 binding helix and also the hydrophobic core region of the Ts sigma(A) factor were readily exposed on the protein surface. This hydrophobic exposure provides an important cue for mutual interaction between molecules of the Ts sigma(A) and allows the formation of multimeric Ts sigma(A). Our results also indicate that Ile-198 and Ile-202 on the hydrophobic face of the promoter -10 binding helix are essential to ensure the correct folding and stabilization of the functional structure of sigma(A) factor.
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Affiliation(s)
- Y D Wen
- Institute of Biochemistry, National Chung-Hsing University, Taiwan, Republic of China
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Abstract
PURPOSE To compare the incidence of anterior intraocular lens (IOL) precipitates on silicone and poly(methyl methacrylate) (PMMA) IOLs after phacotrabeculetomy. SETTING District general hospital in the United Kingdom. METHODS Ninety-five consecutive eyes of 77 patients who had combined phacotrabeculectomy between April 1992 and October 1996 were retrospectively studied. A slitlamp biomicroscope was used to look for precipitates. RESULTS Mean patient age was 75 years (range 51 to 89 years). Preoperatively, mean intraocular pressure (IOP) was 26 mm Hg +/- 5.26 (SD). Thirty plate-haptic silicone IOLs and 65 PMMA IOLs were implanted. Six months postoperatively, median corrected Snellen acuity improved from 6/18 to 6/9. The mean number of antiglaucoma medications dropped from 1.46 preoperatively to 0.29 postoperatively; 73 eyes (76.8%) had an IOP of less than 22 mm Hg with no medication. In 1 surgeon's experience, lens precipitates appeared in 10 of 59 cases (16.9%), with 7 of 14 (50.0%) in the silicone IOL group and 3 of 45 (6.7%) in the PMMA IOL group. The difference was statistically significant (P <.001, chi-square). CONCLUSION The incidence of anterior IOL precipitates was significantly higher in patients with a silicone IOL than in those with a PMMA IOL, suggesting that use of silicone IOLs may increase the incidence of postoperative IOL precipitates.
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Affiliation(s)
- B Y Chang
- Department of Ophthalmology, Bradford Royal Infirmary, Bradford, United Kingdom
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Chang BY, Davey KG, Gupta M, Hutchinson C. Late clouding of an acrylic intraocular lens following routine phacoemulsification. Eye (Lond) 1999; 13 ( Pt 6):807-8. [PMID: 10707158 DOI: 10.1038/eye.1999.241] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Liao CT, Wang WH, Yang HS, Chen JP, Chang BY. Differential and additive effects of the three conserved isoleucine residues in the promoter -10 binding region on Bacillus subtilis sigma(A) structure and function. J Biochem 1999; 126:461-9. [PMID: 10467160 DOI: 10.1093/oxfordjournals.jbchem.a022474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The promoter -10 binding region of the Bacillus subtilis sigma(A) factor forms an amphiphilic alpha-helix with three conserved isoleucines located at four-residue intervals. To investigate the structural and functional roles of the three isoleucine residues, we constructed a series of sigA mutants with single and double Ile-to-Ala substitutions on the hydrophobic face of this alpha-helix and isolated intragenic revertants with either same-site or second-site suppressor that partially restores the structural stability and transcription activity of the mutant sigma(A) factors. Our data show that the three conserved isoleucine residues (Ile-194, Ile-198, and Ile-202) are involved in the hydrophobic core packing of sigma(A); they affect differentially and additively the structure and function of sigma(A), with the central isoleucine residue (Ile-198) playing the most important role. By analogy with the crystal structure of a sigma(70) peptide, it is apparent that interdigital interactions exist between the three conserved isoleucine residues and certain hydrophobic amino acids in region 2. 1 of sigma(A). They include at least the van der Waals contacts between Ile-194 and both Leu-145 and Ile-149, between Ile-198 and both Ile-149 and Tyr-153, as well as between Ile-202 and Tyr-153. The same-site suppressors, Val-194 and Val-198, restore the structural stability and transcription activity of sigma(A) by repacking the hydrophobic core of sigma(A). The second-site suppressor (S291F) appears to be allele-specific, but it is not as effective as the same-site suppressors in restoring sigma(A) structure and function.
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Affiliation(s)
- C T Liao
- Institute of Biochemistry, National Chung-Hsing University, Taichung, 40227, Taiwan
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