Publications by authors named "Pin Lu"

45 Publications

Ibrutinib and venetoclax target distinct subpopulations of CLL cells: implication for residual disease eradication.

Blood Cancer J 2021 Feb 18;11(2):39. Epub 2021 Feb 18.

Fox Chase Cancer Center, Philadelphia, PA, USA.

Ibrutinib inhibits Bruton tyrosine kinase while venetoclax is a specific inhibitor of the anti-apoptotic protein BCL2. Both drugs are highly effective as monotherapy against chronic lymphocytic leukemia (CLL), and clinical trials using the combination therapy have produced remarkable results in terms of rate of complete remission and frequency of undetectable minimal residual disease. However, the laboratory rationale behind the success of the drug combination is still lacking. A better understanding of how these two drugs synergize would eventually help develop other rational combination strategies. Using an ex vivo model that promotes CLL proliferation, we show that modeled ibrutinib proliferative responses, but not viability responses, correlate well with patients' actual clinical responses. Importantly, we demonstrate for the first time that ibrutinib and venetoclax act on distinct CLL subpopulations that have different proliferative capacities. While the dividing subpopulation of CLL responds to ibrutinib, the resting subpopulation preferentially responds to venetoclax. The combination of these targeted therapies effectively reduced both the resting and dividing subpopulations in most cases. Our laboratory findings help explain several clinical observations and contribute to the understanding of tumor dynamics. Additionally, our proliferation model may be used to identify novel drug combinations with the potential of eradicating residual disease.
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http://dx.doi.org/10.1038/s41408-021-00429-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7893066PMC
February 2021

Electrochemical metrics for corrosion resistant alloys.

Sci Data 2021 Feb 11;8(1):58. Epub 2021 Feb 11.

Department of Materials Science and Engineering, Ohio State University, Columbus, OH, 43210, USA.

Corrosion is an electrochemical phenomenon. It can occur via different modes of attack, each having its own mechanisms, and therefore there are multiple metrics for evaluating corrosion resistance. In corrosion resistant alloys (CRAs), the rate of localized corrosion can exceed that of uniform corrosion by orders of magnitude. Therefore, instead of uniform corrosion rate, more complex electrochemical parameters are required to capture the salient features of corrosion phenomena. Here, we collect a database with an emphasis on metrics related to localized corrosion. The six sections of the database include data on various metal alloys with measurements of (1) pitting potential, E, (2) repassivation potential, E, (3) crevice corrosion potential, E, (4) pitting temperature, T, (5) crevice corrosion temperature, T, and (6) corrosion potential, E, corrosion current density, i, passivation current density, i, and corrosion rate. The experimental data were collected from 85 publications and include Al- and Fe-based alloys, high entropy alloys (HEAs), and a Ni-Cr-Mo ternary system. This dataset could be used in the design of highly corrosion resistant alloys.
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http://dx.doi.org/10.1038/s41597-021-00840-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7878803PMC
February 2021

Inhibition of B-cell receptor signaling disrupts cell adhesion in mantle cell lymphoma via RAC2.

Blood Adv 2021 Jan;5(1):185-197

Blood Cell Development and Function Program, Fox Chase Cancer Center, Philadelphia, PA.

Inhibition of the B-cell receptor (BCR) signaling pathway is highly effective in B-cell neoplasia through Bruton tyrosine kinase inhibition by ibrutinib. Ibrutinib also disrupts cell adhesion between a tumor and its microenvironment. However, it is largely unknown how BCR signaling is linked to cell adhesion. We observed that intrinsic sensitivities of mantle cell lymphoma (MCL) cell lines to ibrutinib correlated well with their cell adhesion phenotype. RNA-sequencing revealed that BCR and cell adhesion signatures were simultaneously downregulated by ibrutinib in the ibrutinib-sensitive, but not ibrutinib-resistant, cells. Among the differentially expressed genes, RAC2, part of the BCR signature and a known regulator of cell adhesion, was downregulated at both the RNA and protein levels by ibrutinib only in sensitive cells. RAC2 physically associated with B-cell linker protein (BLNK), a BCR adaptor molecule, uniquely in sensitive cells. RAC2 reduction using RNA interference and CRISPR impaired cell adhesion, whereas RAC2 overexpression reversed ibrutinib-induced cell adhesion impairment. In a xenograft mouse model, mice treated with ibrutinib exhibited slower tumor growth, with reduced RAC2 expression in tissue. Finally, RAC2 was expressed in ∼65% of human primary MCL tumors, and RAC2 suppression by ibrutinib resulted in cell adhesion impairment. These findings, made with cell lines, a xenograft model, and human primary lymphoma tumors, uncover a novel link between BCR signaling and cell adhesion. This study highlights the importance of RAC2 and cell adhesion in MCL pathogenesis and drug development.
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http://dx.doi.org/10.1182/bloodadvances.2020001665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7805322PMC
January 2021

Influence of Calcium Perchlorate on the Search for Organics on Mars with Tetramethylammonium Hydroxide Thermochemolysis.

Astrobiology 2020 Dec 11. Epub 2020 Dec 11.

Space Science Exploration Division (Code 690), NASA Goddard Space Flight Center, Greenbelt, Maryland, USA.

The Mars Organic Molecule Analyzer (MOMA) and Sample Analysis at Mars (SAM) instruments onboard the Exomars 2022 and Mars Science Laboratory rovers, respectively, are capable of organic matter detection and differentiating potentially biogenic from abiotic organics in martian samples. To identify organics, both these instruments utilize pyrolysis-gas chromatography coupled to mass spectrometry, and the thermochemolysis agent tetramethylammonium hydroxide (TMAH) is also used to increase organic volatility. However, the reactivity and efficiency of TMAH thermochemolysis are affected by the presence of calcium perchlorate on the martian surface. In this study, we determined the products of TMAH pyrolysis in the presence and absence of calcium perchlorate at different heating rates (flash pyrolysis and SAM-like ramp pyrolysis with a 35°C·min heating rate). The decomposition mechanism of TMAH pyrolysis in the presence of calcium perchlorate was studied by using stepped pyrolysis. Moreover, the effect of calcium perchlorate (at Mars-relevant concentrations) on the recovery rate of fatty acids with TMAH thermochemolysis was studied. Results demonstrate that flash pyrolysis yields more diversity and greater abundances of TMAH thermochemolysis products than does the SAM-like ramp pyrolysis method. There is no obvious effect of calcium perchlorate on TMAH degradation when the [ClO] is lower than 10 weight percent (wt %). Most importantly, the presence of calcium perchlorate does not significantly impact the recovery rate of fatty acids with TMAH thermochemolysis under laboratory conditions, which is promising for the detection of fatty acids via TMAH thermochemolysis with the SAM and MOMA instruments on Mars.
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http://dx.doi.org/10.1089/ast.2020.2252DOI Listing
December 2020

Banxia Xiexin Decoction () Treats Diabetic Gastroparesis through PLC-IP-Ca/NO-cGMP-PKG Signal Pathway.

Chin J Integr Med 2020 Nov 16;26(11):833-838. Epub 2020 May 16.

Department of Gastroenterology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China.

Objective: To test the effect of Banxia Xiexin Decoction (, BXD) on the contraction and relaxation of gastric smooth muscle (SM) in diabetic gastroparesis (DGP) model rats, and to explore the mechanism of BXD in the prevention and treatment of DGP through experiments of signal pathway both in vivo and in vitro.

Methods: Sixty Sprague-Dawley rats were divided into 6 groups according to a random number table: control group, model group, high-, medium- and low-dose BXD groups (9.2, 4.6 and 1.8 g/(kg·d), respectively), and domperidone group (10 mg/(kg·d)), 10 rats per group. DGP model was established initially by a single intraperitoneal injection of streptozotocin (STZ), and was confirmed by recording gastric emptying, intestinal transport velocity and gastric myoelectric activity of rats after 2 months. Each group was treated with a corresponding drug for 4 weeks. The mRNA and protein expressions of phospholipase C (PLC), inositol triphosphate (IP), neuronal nitric oxide synthase (nNOS), and cyclic guanosine monophosphate (cGMP) dependent protein kinase G (PKG) were detected by reverse transcription-polymerase chain reaction and Western blot, respectively, while nitric oxide (NO) and cGMP expressions were detected by enzyme-linked immunosorbent assay. Gastric tissues were obtained from rats for primary cell culture preparation. Gastric SM cells were treated with 0.8 µmol/L of STZ or STZ plus 1,000, 500 and 200 µg/mL of BXD or STZ plus 2.5 µmol/mL of domperidone for 24, 48, 72 or 96 h, respectively. The length of gastric SM cells and intracellular Ca concentration ([Ca]) before and after BXD treatment was measured.

Results: Compared with the model group, high- and medium-dose BXD and domperidone significantly increased the expressions of PLC, IP, NO, nNOS, cGMP and PKG in rat's gastric tissue (P<0.01). Gastric SM cells treated with BXD showed a time- and dose-dependent increase in cell viability (P<0.01). The treatment with high- and medium-dose BXD and domperidone inhibited the increase in gastric SM cells length and increased [Ca] compared with the model cells (P<0.01).

Conclusions: Treatment with high- and medium-dose BXD significantly attenuated STZ-induced experimental DGP in rats. The therapeutic effect of BXD on DGP rats might be associated with the PLC-IP-Ca/NO-cGMP-PKG signal pathway.
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http://dx.doi.org/10.1007/s11655-020-3077-8DOI Listing
November 2020

Molecular insights into the thermal stability of gold superlattices.

Nanotechnology 2019 Nov 5;31(8):085704. Epub 2019 Nov 5.

Anhui Province Key Lab of Aerospace Structural Parts Forming Technology and Equipment, Institute of Industry and Equipment Technology, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China. CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China. School of Mechanical Engineering, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China.

Atomistic molecular dynamics simulations are performed to study the thermal stability of bulk superlattices consisting of alkylthiol-coated gold nanocrystals. Using nanocrystals passivated by dodecanethiol chains, we show that the gold superlattice possesses a remarkable high-temperature stability, in agreement with experiment. When heated from room temperature, the superlattice expands slightly at lower temperature (<500 K) and then exhibits a considerable lattice contraction above 500 K, while maintaining the intact crystal structure up to 710 K. Once the temperature increases above 720 K, the gold superlattice becomes structurally unstable due to the local sintering of adjacent nanocrystals. Continuous heating to 750 K drives a large number of gold nanocrystals to coalesce and finally results in a tremendous destruction of the superstructure. The structural change and instability of superlattice are mainly attributed to the ligand desorption from nanocrystal surface induced by the variation in temperature. Furthermore, longer ligand length can effectively improve the thermal stability of gold superlattices. These findings are expected to provide a deep microscopic understanding of the thermal stability of superlattice materials.
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http://dx.doi.org/10.1088/1361-6528/ab546dDOI Listing
November 2019

Macro- and Microscopic Analyses of Anatomical Structures of Chinese Gallnuts and Their Functional Adaptation.

Sci Rep 2019 03 26;9(1):5193. Epub 2019 Mar 26.

Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, 650224, China.

The galls induced by Schlechtendaia chinensis, Schlechtendaia peitan and Nurudea shiraii on Rhus chinensis and gall induced by Kaburagia rhusicola rhusicola on Rhus potaninii Maxim. are the largest plant galls and have great economic and medical values. We examined the structures of galls and their functional adaptation using various macro- and microscopic techniques. The highly adapted structures include a stalk at the base that is specialized for mechanical support and transport of nutrients for aphids, and a network of vascular bundles which accompanying schizogenous ducts arranged in a way to best support aphid feeding and population growth. There are many circular and semicircular xylems traces in an ensiform gall in cross sectional views, which would provide more nutrition and occupy less space. We infer the evolution trail was flower-like gall, horned gall, circular gall and ensiform gall. And the possible evolutionary trend of the gall was bigger chamber, more stable mechanical supporting, easier for exchanging substance and transporting nutrients.
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http://dx.doi.org/10.1038/s41598-019-41656-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6435719PMC
March 2019

Metabolic Detection of Bruton's Tyrosine Kinase Inhibition in Mantle Cell Lymphoma Cells.

Mol Cancer Res 2019 06 12;17(6):1365-1377. Epub 2019 Mar 12.

Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.

Current methods to evaluate effects of kinase inhibitors in cancer are suboptimal. Analysis of changes in cancer metabolism in response to the inhibitors creates an opportunity for better understanding of the interplay between cell signaling and metabolism and, from the translational perspective, potential early evaluation of response to the inhibitors as well as treatment optimization. We performed genomic, metabolomic, and fluxomic analyses to evaluate the mechanism of action of the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib (IBR) in mantle cell lymphoma (MCL) cells. Our comprehensive analysis of the data generated by these diverse technologies revealed that IBR profoundly affected key metabolic pathways in IBR-sensitive cells including glycolysis, pentose phosphate pathway, TCA cycle, and glutaminolysis while having much less effects on IBR-poorly responsive cells. Changes in H magnetic resonance spectroscopy (MRS)-detectable lactate and alanine concentrations emerged as promising biomarkers of response and resistance to IBR as demonstrated from experiments on various MCL cell lines. The metabolic network analysis on the C MRS and C LC/MS experimental data provided quantitative estimates of various intracellular fluxes and energy contributions. Glutaminolysis contributed over 50% of mitochondrial ATP production. Administration of the glutaminase inhibitor CB-839 induced growth suppression of the IBR-poorly responsive cells. IMPLICATIONS: Our study demonstrates application of the advanced metabolomic/fluxomic techniques for comprehensive, precise, and prompt evaluations of the effects of kinase inhibition in MCL cells and has strong translational implications by potentially permitting early evaluation of cancer patient response versus resistance to kinase inhibitors and on design of novel therapies for overcoming the resistance.
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http://dx.doi.org/10.1158/1541-7786.MCR-18-0256DOI Listing
June 2019

Molecular interaction between asymmetric ligand-capped gold nanocrystals.

J Chem Phys 2019 Jan;150(3):034702

Anhui Province Key Lab of Aerospace Structural Parts Forming Technology and Equipment, Institute of Industry and Equipment Technology, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China.

Atomistic molecular dynamics simulations are performed to study the potential of mean force (PMF) between two asymmetric gold nanocrystals (NCs) capped by alkylthiols in a vacuum. We systematically investigate the dependence of the PMF on the sizes and capping ligand lengths of two NCs. The results show that the potential well depth scales linearly with increasing total length of two capping ligands on asymmetric dimers, but it hardly depends on the NC size. The predicted equilibrium distance between two asymmetric NCs grows significantly and linearly with the total size of two NCs and exhibits only a slight increase with increasing total ligand length. These findings are explained in terms of the amount of ligand interdigitation between NC surfaces as well as its alterations caused by the change in ligand length and NC size. Furthermore, we introduce a simple formula to estimate the equilibrium distance of two asymmetric NCs. On the basis of the computed PMFs, we propose an empirical two-body potential between asymmetric capped gold NCs.
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http://dx.doi.org/10.1063/1.5065476DOI Listing
January 2019

XPO1 Inhibitor Selinexor Overcomes Intrinsic Ibrutinib Resistance in Mantle Cell Lymphoma via Nuclear Retention of IκB.

Mol Cancer Ther 2018 12;17(12):2564-2574

Department of Pathology, University of Chicago, Chicago, Illinois.

Inhibition of B-cell receptor (BCR) signaling through the BTK inhibitor, ibrutinib, has generated a remarkable response in mantle cell lymphoma (MCL). However, approximately one third of patients do not respond well to the drug, and disease relapse on ibrutinib is nearly universal. Alternative therapeutic strategies aimed to prevent and overcome ibrutinib resistance are needed. We compared and contrasted the effects of selinexor, a selective inhibitor of nuclear export, with ibrutinib in six MCL cell lines that display differential intrinsic sensitivity to ibrutinib. We found that selinexor had a broader antitumor activity in MCL than ibrutinib. MCL cell lines resistant to ibrutinib remained sensitive to selinexor. We showed that selinexor induced apoptosis/cell-cycle arrest and XPO-1 knockdown also retarded cell growth. Furthermore, downregulation of the NFκB gene signature, as opposed to BCR signature, was a common feature that underlies the response of MCL to both selinexor and ibrutinib. Meanwhile, unaltered NFκB was associated with ibrutinib resistance. Mechnistically, selinexor induced nuclear retention of IκB that was accompanied by the reduction of DNA-binding activity of NFκB, suggesting that NFκB is trapped in an inhibitory complex. Coimmunoprecipitation confirmed that p65 of NFκB and IκB were physically associated. In primary MCL tumors, we further demonstrated that the number of cells with IκB nuclear retention was linearly correlated with the degree of apoptosis. Our data highlight the role of NFκB pathway in drug response to ibrutinib and selinexor and show the potential of using selinexor to prevent and overcome intrinsic ibrutinib resistance through NFκB inhibition.
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http://dx.doi.org/10.1158/1535-7163.MCT-17-0789-ATRDOI Listing
December 2018

Cerdulatinib Pharmacodynamics and Relationships to Tumor Response Following Oral Dosing in Patients with Relapsed/Refractory B-cell Malignancies.

Clin Cancer Res 2019 02 17;25(4):1174-1184. Epub 2018 Oct 17.

Biology, Portola Pharmaceuticals, Inc., South San Francisco, California.

Purpose: Preclinical studies suggest SYK and JAK contribute to tumor-intrinsic and microenvironment-derived survival signals. The pharmacodynamics of cerdulatinib, a dual SYK/JAK inhibitor, and associations with tumor response were investigated.

Patients And Methods: In a phase I dose-escalation study in adults with relapsed/refractory B-cell malignancies, cerdulatinib was administered orally to sequential dose-escalation cohorts using once-daily or twice-daily schedules. The study enrolled 8 patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL), 13 with follicular lymphoma, 16 with diffuse large B-cell lymphoma (DLBCL), and 6 with mantle cell lymphoma. Correlation of tumor response with pharmacodynamic markers was determined in patients with meaningful clinical responses.

Results: Following cerdulatinib administration, complete SYK and JAK pathway inhibition was achieved in whole blood of patients at tolerated exposures. Target inhibition correlated with serum cerdulatinib concentration, and IC values against B-cell antigen receptor (BCR), IL2, IL4, and IL6 signaling pathways were 0.27 to 1.11 μmol/L, depending on the phosphorylation event. Significant correlations were observed between SYK and JAK pathway inhibition and tumor response. Serum inflammation markers were reduced by cerdulatinib, and several significantly correlated with tumor response. Diminished expression of CD69 and CD86 (B-cell activation markers), CD5 (negative regulator of BCR signaling), and enhanced expression of CXCR4 were observed in 2 patients with CLL, consistent with BCR and IL4 suppression and loss of proliferative capacity.

Conclusions: Cerdulatinib potently and selectively inhibited SYK/JAK signaling at tolerated exposures in patients with relapsed/refractory B-cell malignancies. The extent of target inhibition in whole-blood assays and suppression of inflammation correlated with tumor response. (ClinicalTrials.gov ID:NCT01994382).
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http://dx.doi.org/10.1158/1078-0432.CCR-18-1047DOI Listing
February 2019

A powerful dual-responsive soft actuator and photo-to-electric generator based on graphene micro-gasbags for bioinspired applications.

J Mater Chem B 2018 Aug 27;6(31):5031-5038. Epub 2018 Jun 27.

Institute of Industry & Equipment Technology, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.

Soft actuators with large deformation and high output force in response to multi-stimuli are highly demanded for the development of biomimetic applications. Here, a bilayer actuator composed of spongy graphene with internal gasbag microstructures and the commercial polyimide adhesive tape is fabricated by a simple and fast method. This actuator produces large deformation, high output force, and dual-stimuli response, owing to the deformation of graphene micro-gasbags coupled with the thermal expansion of polyimide, and the electrothermal and photothermal properties of graphene. Experiments show that upon low voltage (16 V) stimulation the fabricated actuator with a length of 30 mm could generate a bending curvature of 0.55 cm in 5 s, and can simultaneously produce high output force and lift an object 20 times heavier than its own weight. Moreover, a curvature of 0.45 cm can be achieved for the actuator upon light irradiation for 10 s. Based on this bilayer actuator, diversely biomimetic motions including kicking a ball, grabbing a vegetable leaf, human hand movement, and creeping motion are realized, revealing its potential application in soft robotics, artificial muscles, wearable electronics, and biomedical devices. Besides the mechanical deformation output, a photo-to-electric generator is also assembled by associating this actuator with commonly triboelectric materials, further enriching the application range of soft actuators.
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http://dx.doi.org/10.1039/c8tb01222aDOI Listing
August 2018

Activation of MYC, a bona fide client of HSP90, contributes to intrinsic ibrutinib resistance in mantle cell lymphoma.

Blood Adv 2018 08;2(16):2039-2051

Lymphoma Translational Pathology, Department of Pathology, University of Chicago, Chicago, IL.

The BTK inhibitor ibrutinib has demonstrated a remarkable therapeutic effect in mantle cell lymphoma (MCL). However, approximately one-third of patients do not respond to the drug initially. To identify the mechanisms underlying primary ibrutinib resistance in MCL, we analyzed the transcriptome changes in ibrutinib-sensitive and ibrutinib-resistant cell lines on ibrutinib treatment. We found that MYC gene signature was suppressed by ibrutinib in sensitive but not resistant cell lines. We demonstrated that MYC gene was structurally abnormal and MYC protein was overexpressed in MCL cells. Further, MYC knockdown with RNA interference inhibited cell growth in ibrutinib-sensitive as well as ibrutinib-resistant cells. We explored the possibility of inhibiting MYC through HSP90 inhibition. The chaperon protein is overexpressed in both cell lines and primary MCL cells from the patients. We demonstrated that MYC is a bona fide client of HSP90 in the context of MCL by both immunoprecipitation and chemical precipitation. Furthermore, inhibition of HSP90 using PU-H71 induced apoptosis and caused cell cycle arrest. PU-H71 also demonstrates strong and relatively specific inhibition of the MYC transcriptional program compared with other oncogenic pathways. In a MCL patient-derived xenograft model, the HSP90 inhibitor retards tumor growth and prolongs survival. Last, we showed that PU-H71 induced apoptosis and downregulated MYC protein in MCL cells derived from patients who were clinically resistant to ibrutinib. In conclusion, MYC activity underlies intrinsic resistance to ibrutinib in MCL. As a client protein of HSP90, MYC can be inhibited via PU-H71 to overcome primary ibrutinib resistance.
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http://dx.doi.org/10.1182/bloodadvances.2018016048DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6113611PMC
August 2018

Clonal evolution underlying leukemia progression and Richter transformation in patients with ibrutinib-relapsed CLL.

Blood Adv 2017 May 2;1(12):715-727. Epub 2017 May 2.

Department of Pathology.

Ibrutinib has generated remarkable responses in patients with chronic lymphocytic leukemia (CLL), including those with an unfavorable cytogenetic profile. However, patients develop resistance, with poor outcomes and no established treatment options. Mutations in and have emerged as main mechanisms of drug resistance, but not all patients carry these mutations. Further understanding of mechanisms of resistance is urgently needed and will support rational development of new therapeutic strategies. To that end, we characterized the genomic profiles of serial samples from 9 patients with ibrutinib-relapsed disease, including 6 who had Richter transformation. Mutations, indels, copy-number aberrations, and loss of heterozygosity were assessed using next-generation sequencing and single-nucleotide polymorphism array. We found that 18p deletion (del(18p)), together with del(17p)/ mutations, was present in 5 of 9 patients before ibrutinib therapy. In addition to , we identified , a structurally novel mutation located in the SH2 domain of BTK. Minor clones with low allele frequencies were captured in addition to major clones. Although loss predisposes patients for relapse, clone size of loss may diminish during disease progression while mutant clone expands. In patients who had Richter transformation, we found that the transformed cells were clonal descendants of circulating leukemia cells but continued to undergo evolution and drifts. Surprisingly, transformed lymphoma cells in tissue may acquire a different mutation from that in the CLL leukemia cells. Collectively, these results provide insights into clonal evolution underlying ibrutinib relapse and prompt further investigation on genomic abnormalities that have clinical application potential.
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http://dx.doi.org/10.1182/bloodadvances.2016003632DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5728051PMC
May 2017

MEX3C interacts with adaptor-related protein complex 2 and involves in miR-451a exosomal sorting.

PLoS One 2017 5;12(10):e0185992. Epub 2017 Oct 5.

Institute for Regenerative Medicine, Wake Forest University Health Sciences, Winston Salem, North Carolina, United States of America.

Some RNA species, especially microRNAs, are non-randomly sorted into exosomes, but how selectivity of RNA exosomal sorting is achieved is unknown. We found that all three variants of RNA-binding ubiquitin E3 ligase (MEX3C)-MEX3C-1, MEX3C-2, and MEX3C-3 -interact with adaptor-related protein complex 2 (AP-2), a cargo adaptor in clathrin-mediated endocytosis. MEX3C's C-terminal RING finger domain and the hnRNP K homology (KH) domain shared by the three MEX3C variants are both necessary for MEX3C/AP-2 interaction. MEX3C associates with the endolysosomal compartment through an endocytosis-like process. siRNA-mediated inhibition of the MEX3C or AP-2 complex substantially decreased exosomal but not cellular microRNA miR-451a expression. Exosomal sorting is ceramide-dependent but not ESCRT-dependent in microRNA miR-451a. That RNA-binding protein associates with membrane trafficking machinery, and that its involvement in exosomal microRNA expression, suggest the existence of a mechanism for specific recruiting of RNA molecules to endosomes for subsequent exosomal sorting.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185992PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5628917PMC
November 2017

No evidence of genome editing activity from Natronobacterium gregoryi Argonaute (NgAgo) in human cells.

PLoS One 2017 11;12(5):e0177444. Epub 2017 May 11.

Wake Forest Institute for Regenerative Medicine, Wake Forest University Health Sciences, Winston-Salem, North Carolina, United States of America.

The argonaute protein from the thermophilic bacterium Thermus thermophilus shows DNA-guided DNA interfering activity at high temperatures, complicating its application in mammalian cells. A recent work reported that the argonaute protein from Natronobacterium gregoryi (NgAgo) had DNA-guided genome editing activity in mammalian cells. We compared the genome editing activities of NgAgo and Staphylococcus aureus Cas9 (SaCas9) in human HEK293T cells side by side. EGFP reporter assays and DNA sequencing consistently revealed high genome editing activity from SaCas9. However, these assays did not demonstrate genome editing activity by NgAgo. We confirmed that the conditions allowed simultaneous transfection of the NgAgo expressing plasmid DNA and DNA guides, as well as heterologous expression of NgAgo in the HEK293T cells. Our data show that NgAgo is not a robust genome editing tool, although it may have such activity under other conditions.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0177444PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5426773PMC
September 2017

Dual SYK/JAK inhibition overcomes ibrutinib resistance in chronic lymphocytic leukemia: Cerdulatinib, but not ibrutinib, induces apoptosis of tumor cells protected by the microenvironment.

Oncotarget 2017 Feb;8(8):12953-12967

Department of Pathology, Lymphoma Translational Pathology, University of Chicago, Chicago, IL, USA.

Ibrutinib (BTK inhibitor) has generated remarkable responses in CLL. However, the drug, to a large extent, does not cause cell death directly and does not eradicate CLL malignant clones. Inability to eradicate CLL has fostered resistance generation. Once patients become resistant, they do poorly with a median survival of 3-4 months. Novel therapeutic strategies are needed to prevent resistance, improve treatment outcome and ultimately cure the disease. Herein, we explore dual targeting of the BCR and JAK-STAT pathways with a novel single agent, cerdulatinib, which selectively inhibits both SYK (a BCR component) and JAK kinases. We demonstrated that cerdulatinib delivered potent tumor inhibition in 60 primary CLL patient samples, especially in those with poor prognostic indicators. Importantly, cerdulatinib, but not ibrutinib, is able to overcome the support of microenvironment and induces CLL cell death at clinically achievable concentrations. Notably, cerdulatinib blocked proliferation of ibrutinib-resistant primary CLL cells and of BTKC481S-transfected/ibrutinib-resistant lymphoma cells. These anti-tumor effects are well correlated with the inhibition of BCR and JAK-STAT signaling and downstream inhibition of the functions of AKT, ERK and NFκB. Collectively, our results show that simultaneous targeting of BCR and JAK-STAT pathways is a more effective strategy relative to single BTK inhibition.
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http://dx.doi.org/10.18632/oncotarget.14588DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5355069PMC
February 2017

Expression of Long Interspersed Nuclear Element 1 Retroelements and Induction of Type I Interferon in Patients With Systemic Autoimmune Disease.

Arthritis Rheumatol 2016 11;68(11):2686-2696

Hospital for Special Surgery, New York, New York.

Objective: Increased expression of type I interferon (IFN) and a broad signature of type I IFN-induced gene transcripts are observed in patients with systemic lupus erythematosus (SLE) and other systemic autoimmune diseases. To identify disease-relevant triggers of the type I IFN pathway, this study sought to investigate whether endogenous virus-like genomic repeat elements, normally silent, are expressed in patients with systemic autoimmune disease, and whether these retroelements could activate an innate immune response and induce type I IFN.

Methods: Expression of type I IFN and long interspersed nuclear element 1 (LINE-1; L1) was studied by polymerase chain reaction, Western blotting, and immunohistochemistry in samples of kidney tissue from patients with lupus nephritis and minor salivary gland (MSG) tissue from patients with primary Sjögren's syndrome (SS). Induction of type I IFN by L1 was investigated by transfection of plasmacytoid dendritic cells (PDCs) or monocytes with an L1-encoding plasmid or L1 RNA. Involvement of innate immune pathways and altered L1 methylation were assessed.

Results: Levels of L1 messenger RNA transcripts were increased in lupus nephritis kidneys and in MSG tissue from patients with SS. Transcript expression correlated with the expression of type I IFN and L1 DNA demethylation. L1 open-reading frame 1/p40 protein and IFNβ were expressed in MSG ductal epithelial cells and in lupus nephritis kidneys, and IFNα was detected in infiltrating PDCs. Transfection of PDCs or monocytes with L1-encoding DNA or RNA induced type I IFN. Inhibition of Toll-like receptor 7 (TLR-7)/TLR-8 reduced the induction of IFNα by L1 in PDCs, and an inhibitor of IKKε/TANK-binding kinase 1 abrogated the induction of type I IFN by L1 RNA in monocytes.

Conclusion: L1 genomic repeat elements represent endogenous nucleic acid triggers of the type I IFN pathway in SLE and SS and may contribute to initiation or amplification of autoimmune disease.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5083133PMC
http://dx.doi.org/10.1002/art.39795DOI Listing
November 2016

Identification of a structurally novel BTK mutation that drives ibrutinib resistance in CLL.

Oncotarget 2016 Oct;7(42):68833-68841

Department of Pathology, University of Chicago, Chicago, IL 60637, USA.

Ibrutinib (ibr), a first-in-class Bruton tyrosine kinase (BTK) inhibitor, has demonstrated high response rates in both relapsed/refractory and treatment naïve chronic lymphocytic leukemia (CLL). However, about 25% of patients discontinue ibrutinib therapy at a median follow-up of 20 months and many patients discontinue the treatment due to leukemia progression or Richter transformation. Mutations affecting the C481 residue of BTK disrupt ibrutinib binding and have been characterized by us and others as the most common mechanism of ibrutinib resistance. Thus far, all described BTK mutations are located in its kinase domain and mutations outside this domain have never been described. Herein, we report a patient whose CLL progressed, was salvaged with ibrutinib and then relapsed. Serial analysis of samples throughout patient's clinical course identified a structurally novel mutation (BTKT316A) in the SH2 domain, but not kinase domain, of Bruton tyrosine kinase which was associated with disease relapse. Functionally, cells carrying BTKT316A show resistance to ibrutinib at both cellular and molecular levels to a similar extent as BTKC481S. Our study lends further insight into the diverse mechanisms of ibrutinib resistance that has important implications for the development of next-generation BTK inhibitors as well as mutation detection in relapsed patients.
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http://dx.doi.org/10.18632/oncotarget.11932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5356593PMC
October 2016

Heightened BTK-dependent cell proliferation in unmutated chronic lymphocytic leukemia confers increased sensitivity to ibrutinib.

Oncotarget 2016 Jan;7(4):4598-610

Division of Genomic and Molecular Pathology, Department of Pathology, University of Chicago, Chicago, IL, USA.

In chronic lymphocytic leukemia (CLL), patients with unmutated immunoglobulin heavy chain variable region gene (UM-CLL) have worse outcomes than mutated CLL (M-CLL) following chemotherapy or chemoimmunotherapy. However, in the era of BCR-targeted therapies, the adverse prognostic impact of unmutated IGHV seems to be diminishing, and there are clinical datasets showing unexpected improved responses in UM-CLL. We investigated the biological differences of BTK activity between these subgroups and further compared the impact of ibrutinib on molecular and cellular behaviors. Immunoblotting analysis revealed that phosphorylated active BTK is significantly higher in UM-CLL. Moreover, UM-CLL, compared to M-CLL, displayed a much higher proliferative capacity that was correlated with higher phospho-BTK and greater sensitivity to ibrutinib. In addition, BTK depletion with siRNA led to a more prominent reduction in the proliferation of UM-CLL, suggesting that elevated BTK activity is responsible for increased cell proliferation. Further, cell signaling activity by multiple measurements was consistently higher in UM-CLL accompanied by a higher sensitivity to ibrutinib. These studies link UM-CLL to elevated BCR signaling, heightened BTK-dependent cell proliferation and increased sensitivity to ibrutinib. The prognostic significance of IGHV mutation should be reevaluated in the era of new therapies targeting BCR signaling.
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http://dx.doi.org/10.18632/oncotarget.6727DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4826229PMC
January 2016

Generating a Bessel-Gaussian beam for the application in optical engineering.

Sci Rep 2015 Dec 22;5:18665. Epub 2015 Dec 22.

College of Optoelectronic Science and Engineering, National University of Defence Technology, Changsha 410073, China.

Bessel beam is the important member of the family of non-diffracting beams and has many novel properties which can be used in many areas. However, the source of Bessel beam generated by the existing methods can be used only in a short distance due to its low power. In this paper, based on the coherent combining technology, we have proposed a method which can be used to generate a high-power Bessel beam. Even more, we give an innovative idea to form vortex phase by using discontinuous piston phase. To confirm the validity of this method, the intensity evolution of the combined beam and the Bessel-Gaussian beam at different propagation distance have been studied and compared. Meanwhile, the experimental realization has been discussed from the existing experimental result related to the coherent combining technology.
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http://dx.doi.org/10.1038/srep18665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4687037PMC
December 2015

Characterization of ibrutinib-sensitive and -resistant mantle lymphoma cells.

Br J Haematol 2014 Sep 24;166(6):849-61. Epub 2014 Jun 24.

Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA.

Ibrutinib inhibits Bruton tyrosine kinase (BTK), a key component of early B-cell receptor (BCR) signalling pathways. A multicentre phase 2 trial of ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL) demonstrated a remarkable response rate. However, approximately one-third of patients have primary resistance to the drug while other patients appear to lose response and develop secondary resistance. Understanding the molecular mechanisms underlying ibrutinib sensitivity is of paramount importance. In this study, we investigated cell lines and primary MCL cells that display differential sensitivity to ibrutinib. We found that the primary cells display a higher BTK activity than normal B cells and MCL cells show differential sensitivity to BTK inhibition. Genetic knockdown of BTK inhibits the growth, survival and proliferation of ibrutinib-sensitive but not resistant MCL cell lines, suggesting that ibrutinib acts through BTK to produce its anti-tumour activities. Interestingly, inhibition of ERK1/2 and AKT, but not BTK phosphorylation per se, correlates well with cellular response to BTK inhibition in cell lines as well as in primary tumours. Our study suggests that, to prevent primary resistance or to overcome secondary resistance to BTK inhibition, a combinatory strategy that targets multiple components or multiple pathways may represent the most effective approach.
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http://dx.doi.org/10.1111/bjh.12974DOI Listing
September 2014

Targeting the Hsp90-associated viral oncoproteome in gammaherpesvirus-associated malignancies.

Blood 2013 Oct 13;122(16):2837-47. Epub 2013 Aug 13.

Department of Pathology and Laboratory Medicine, and.

PU-H71 is a purine-scaffold Hsp90 inhibitor that, in contrast to other Hsp90 inhibitors, displays unique selectivity for binding the fraction of Hsp90 that is preferentially associated with oncogenic client proteins and enriched in tumor cells (teHsp90). This property allows PU-H71 to potently suppress teHsp90 without inducing toxicity in normal cells. We found that lymphoma cells infected by Epstein-Barr virus or Kaposi sarcoma-associated herpes virus (KSHV) are exquisitely sensitive to this compound. Using PU-H71 affinity capture and proteomics, an unbiased approach to reveal oncogenic networks, we identified the teHsp90 interactome in KSHV(+) primary effusion lymphoma cells. Viral and cellular proteins were identified, including many involved in nuclear factor (NF)-κB signaling, apoptosis, and autophagy. KSHV vFLIP is a viral oncoprotein homologous to cFLIPs, with NF-κB-activating and antiapoptotic activities. We show that teHsp90 binds vFLIP but not cFLIPs. Treatment with PU-H71 induced degradation of vFLIP and IKKγ, NF-κB downregulation, apoptosis and autophagy in vitro, and more importantly, tumor responses in mice. Analysis of the interactome revealed apoptosis as a central pathway; therefore, we tested a BCL2 family inhibitor in primary effusion lymphoma cells. We found strong activity and synergy with PU-H71. Our findings demonstrate PU-H71 affinity capture identifies actionable networks that may help design rational combinations of effective therapies.
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http://dx.doi.org/10.1182/blood-2013-01-479972DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3798998PMC
October 2013

[In vivo study on antisense-micro ribonucleic acid-21 oligonucleotide inhibiting tongue squamous cell carcinoma growth].

Hua Xi Kou Qiang Yi Xue Za Zhi 2012 Dec;30(6):562-7

State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041, China.

Objective: To detect antisense-micro ribonucleic acid-21 oligonucleotide (AS-miR-21)'s inhibiting effect to tongue squamous cell carcinoma.

Methods: Living image and TUNEL experiments were performed, based upon the xenograft animal models set up by introduction of Tca8113-luc cells which were stably transfected with pGL6 luciferase report gene plasmid into nude mice, while the tumors were injected with AS-miR-21.

Results: Tca8113-luc cell line which steadily expressed luciferase activity was constructed by transfecting pGL6 report gene plasmid. The subcutaneous tumor formation rate was much higher in nude mice introduced with the cells, and the tumors grew well. After injection of AS-miR-21 into mice tumors, it was obviously viewed that tumors grew slower, the volume of the tumors was smaller, the photon number in live body imaging was getting less, the necrosis in the tumor specimens was rare, cell nuclei was getting smaller, dyeing color was lighter, heteromorphism and new vessels were decreased, micro ribonucleic acid-21 expression in tumor cells was considerably lower, and apoptotic index was increased.

Conclusion: All the results indicate that the injection of AS-miR-21 can inhibit growth of tongue squamous cell carcinoma in nude mice model, and effectively promote cell apoptosis of tongue squamous cell carcinoma.
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December 2012

[Biological effect of micro ribonucleic acid-21 on human tongue squamous cell carcinoma lines].

Hua Xi Kou Qiang Yi Xue Za Zhi 2012 Aug;30(4):350-5, 359

State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041, China.

Objective: To detect the biological influence to human tongue squamous cell carcinoma (TSCC) cells of micro ribonucleic acid-21 (miR-21).

Methods: Referring to mature miR-21 sequence, the sense and antisense oligonucleotide (sense-miR-21 and AS-miR-21) modified by 2'O-Me were designed to transfect into TSCC cells (Tca8113 and high metastasis cells) by liposome transfection technology, in order to establish an in vitro TSCC cell model. The expression changes of miR-21 in the transfected cells were detected with real-time fluorescence quantitative polymerase chain reaction (real-time PCR). The changes of cell proliferation, cell cycle, cell early apoptosis, cell migration and invasion capabilities were detected respectively by the technologies of methyl thiazolyl tetrazolium (MTT), flow cytometry, Annexin V cell early apoptosis assay, scratch assay and Transwell assay, to check AS-miR-21's effect on the biological characteristics of human TSCC cell lines.

Results: For the TSCC cells, the antisense oligonucleotide of targeting miR-21 could effectively inhibit cell proliferation, promoted cell apoptosis, and inhibited the capability of cell's migration and invasion.

Conclusion: The expressions of miR-21 decrease after AS-miR-21 transfected into TSCC cells, and miR-21 can affect biological behavior of TSCC cells.
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August 2012

[Determination of bisphenol A in plastic parts of small household appliances by liquid chromatography-tandem mass spectrometry].

Se Pu 2012 Jan;30(1):95-8

Beijing Entry-Exit Inspection and Quarantine Bureau, Beijing 100026, China.

A method for the determination of bisphenol A in the plastic parts of small household appliances by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. The sample was extracted with accelerated solvent extraction (ASE) and purified by Sep-Pak C18 solid phase extraction. Bisphenol A was separated and detected using LC-MS/MS in negative ion mode with the mobile phases of methanol and water (containing 0.05% ammonia water). The linearity of the method was good in the range of 5 μg/L to 100 μg/L. The recoveries for the spiked sample were from 95.2% to 109.7% at the three levels, 10, 25 and 75 μg/kg. The relative standard deviations were less than 3.8%. The limit of detection was 10 μg/kg. The method is easy-handling, time-saving, sensitive and suitable for the determination of the residual bisphenol A in the plastic parts of household appliances.
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http://dx.doi.org/10.3724/sp.j.1123.2011.08030DOI Listing
January 2012

SYK inhibition and response prediction in diffuse large B-cell lymphoma.

Blood 2011 Dec 24;118(24):6342-52. Epub 2011 Oct 24.

Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, and the role of SYK in its pathogenesis is not completely understood. Using tissue microarray, we demonstrated for the first time that SYK protein is activated in 27 of 61 (44%) primary human DLBCL tissues. Among DLBCL cell lines, 7 were sensitive and 3 were resistant to a highly specific SYK inhibitor, PRT060318. In sensitive DLBCL cells, SYK inhibition blocked the G(1)-S transition and caused cell-cycle arrest. This effect was reproduced by genetic reduction of SYK using siRNA. A detailed analysis of the BCR signaling pathways revealed that the consequence of SYK inhibition on PLCγ2 and AKT, as opposed to ERK1/2, was responsible for cell-cycle arrest. Genetic knock-down of these key molecules decelerated the proliferation of lymphoma cells. In addition, BCR signaling can be blocked by PRT060318 in primary lymphoma cells. Together, these findings provide insights into cellular pathways required for lymphoma cell growth and support the rationale for considering SYK inhibition as a potentially useful therapy for DLBCL. The results further suggest the possibility of using PLCγ2 and AKT as biomarkers to predict therapeutic response in prospective clinical trials of specific SYK inhibitors.
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http://dx.doi.org/10.1182/blood-2011-02-333773DOI Listing
December 2011

Construction and genetic analysis of murine hepatitis virus strain A59 Nsp16 temperature sensitive mutant and the revertant virus.

Virol Sin 2011 Feb 18;26(1):19-29. Epub 2011 Feb 18.

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China.

Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely studied model system for Coronavirus replication and pathogenesis. In this study, we created a MHV-A59 temperature sensitive (ts) mutant Wu"-ts18(cd) using the recombinant vaccinia reverse genetics system. Virus replication assay in 17C1-1 cells showed the plaque phenotype and replication characterization of constructed Wu"-ts18(cd) were indistinguishable from the reported ts mutant Wu"-ts18. Then we cultured the ts mutant Wu"-ts18(cd) at non-permissive temperature 39.5 °C, which "forced" the ts recombinant virus to use second-site mutation to revert from a ts to a non-ts phenotype. Sequence analysis showed most of the revertants had the same single amino acid mutation at Nsp16 position 43. The single amino acid mutation at Nsp16 position 76 or position 130 could also revert the ts mutant Wu"-ts18 (cd) to non-ts phenotype, an additional independent mutation in Nsp13 position 115 played an important role on plaque size. The results provided us with genetic information on the functional determinants of Nsp16. This allowed us to build up a more reasonable model of CoVs replication-transcription complex.
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http://dx.doi.org/10.1007/s12250-011-3145-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7091325PMC
February 2011

Activities of SYK and PLCgamma2 predict apoptotic response of CLL cells to SRC tyrosine kinase inhibitor dasatinib.

Clin Cancer Res 2010 Jan 12;16(2):587-99. Epub 2010 Jan 12.

Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York 10065, USA.

Purpose: B-cell receptor signaling plays an important role in the pathogenesis of chronic lymphocytic leukemia (CLL). However, blocking B-cell receptor signaling with dasatinib, an inhibitor of SRC kinase, produced variable results in preclinical and clinical studies. We aim to define the molecular mechanisms underlying the differential dasatinib sensitivity and to uncover more effective therapeutic targets in CLL.

Experimental Design: Fresh CLL B cells were treated with dasatinib, and cell viability was followed. The CLL cases were then divided into good and poor responders. The cellular response was correlated with the activities of B-cell receptor signaling molecules, as well as with molecular and cytogenetic prognostic factors.

Results: Among 50 CLL cases, dasatinib treatment reduced cell viability by 2% to 90%, with an average reduction of 47% on day 4 of culture. The drug induced CLL cell death through the intrinsic apoptotic pathway mediated by reactive oxygen species. Unexpectedly, phosphorylation of SRC family kinases was inhibited by dasatinib in good, as well as poor, responders. As opposed to SRC family kinases, activities of two downstream molecules, SYK and phospholipase Cgamma2, correlate well with the apoptotic response of CLL cells to dasatinib.

Conclusions: Thus, SYK inhibition predicts cellular response to dasatinib. SYK, together with phospholipase Cgamma2, may serve as potential biomarkers to predict dasatinib therapeutic response in patients. From the pathogenic perspective, our study suggests the existence of alternative mechanisms or pathways that activate SYK, independent of SRC kinase activities. The study further implicates that SYK might serve as a more effective therapeutic target in CLL treatment.
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http://dx.doi.org/10.1158/1078-0432.CCR-09-1519DOI Listing
January 2010