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1.
Adv Sci (Weinh) ; 9(22): e2201507, 2022 08.
Article En | MEDLINE | ID: mdl-35657078

Smart fabrics that can harvest ambient energy and provide diverse sensing functionality via triboelectric effects have evoked great interest for next-generation healthcare electronics. Herein, a novel borophene/ecoflex nanocomposite is developed as a promising triboelectric material with tailorability, durability, mechanical stability, and flexibility. The addition of borophene nanosheets enables the borophene/ecoflex nanocomposite to exhibit tunable surface triboelectricity investigated by Kelvin probe force microscopy. The borophene/ecoflex nanocomposite is further fabricated into a fabric-based triboelectric nanogenerator (B-TENG) for mechanical energy harvesting, medical assistive system, and wound healing applications. The durability of B-TENG provides consistent output performance even after severe deformation treatments, such as folding, stretching, twisting, and washing procedures. Moreover, the B-TENG is integrated into a smart keyboard configuration combined with a robotic system to perform an upper-limb medical assistive interface. Furthermore, the B-TENG is also applied as an active gait phase sensing system for instantaneous lower-limb gait phase visualization. Most importantly, the B-TENG can be regarded as a self-powered in vitro electrical stimulation device to conduct continuous wound monitoring and therapy. The as-designed B-TENG not only demonstrates great potential for multifunctional self-powered healthcare sensors, but also for the promising advancements toward wearable medical assistive and therapeutic systems.


Nanocomposites , Nanotechnology , Electricity , Nanotechnology/methods , Textiles , Wound Healing
2.
Adv Sci (Weinh) ; 9(18): e2105974, 2022 06.
Article En | MEDLINE | ID: mdl-35445556

Single crystal metal-free halide perovskites have received great attention in recent years owing to their excellent piezoelectric and ferroelectric properties. However, the nanotoxicity and piezoelectricity within the nanoscale of such materials have yet been reported for the demonstration of practical applications. In this work, the observation of intrinsic piezoelectricity in metal-free perovskite (MDABCO-NH4 I3 ) films using piezoresponse force microscopy (PFM) is reported. A cytotoxicity test is also performed on MDABCO-NH4 I3 to evaluate its low-toxic nature. The as-synthesized MDABCO-NH4 I3 is further integrated into a piezoelectric nanogenerator (PENG). The MDABCO-NH4 I3 -based PENG (MN-PENG) exhibits optimal output voltage and current of 15.9 V and 54.5 nA, respectively. In addition, the MN-PENG can serve as a self-powered strain sensor for human-machine interface applications or be adopted in in vitro electrical stimulation devices. This work demonstrates a path of perovskite-based PENG with high performance, low toxicity, and multifunctionality for future advanced wearable sensors and portable therapeutic systems.


Electric Power Supplies , Titanium , Calcium Compounds , Electric Stimulation , Humans , Oxides
3.
Bioorg Med Chem Lett ; 30(23): 127625, 2020 12 01.
Article En | MEDLINE | ID: mdl-33096160
4.
Cancer Immunol Res ; 8(7): 844-850, 2020 07.
Article En | MEDLINE | ID: mdl-32321776

Prostate cancer is the second leading cause of cancer-related death in men. Despite having a relatively lower tumor mutational burden than most tumor types, multiple gene fusions such as TMPRSS2:ERG have been characterized and linked to more aggressive disease. Individual tumor samples have been found to contain multiple fusions, and it remains unknown whether these fusions increase tumor immunogenicity. Here, we investigated the role of fusion burden on the prevalence and expression of key molecular and immune effectors in prostate cancer tissue specimens that represented the different stages of disease progression and androgen sensitivity, including hormone-sensitive and castration-resistant prostate cancer. We found that tumor fusion burden was inversely correlated with tumor mutational burden and not associated with disease stage. High fusion burden correlated with high immune infiltration, PD-L1 expression on immune cells, and immune signatures, representing activation of T cells and M1 macrophages. High fusion burden inversely correlated with immune-suppressive signatures. Our findings suggest that high tumor fusion burden may be a more appropriate biomarker than tumor mutational burden in prostate cancer, as it more closely associates with immunogenicity, and suggests that tumors with high fusion burden could be potential candidates for immunotherapeutic agents.


B7-H1 Antigen/genetics , Biomarkers, Tumor/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Mutation , Oncogene Fusion , Prostatic Neoplasms/genetics , Prostatic Neoplasms/immunology , B7-H1 Antigen/immunology , Biomarkers, Tumor/genetics , Gene Expression Regulation, Neoplastic , Humans , Macrophages/immunology , Male , Neoplasm Grading , Neoplasm Staging , Prostatic Neoplasms/pathology , RNA-Seq/methods
5.
Clin Cancer Res ; 26(6): 1229-1236, 2020 03 15.
Article En | MEDLINE | ID: mdl-31848189

PURPOSE: ERK1/2 signaling can be dysregulated in cancer. GDC-0994 is an oral inhibitor of ERK1/2. A first-in-human, phase I dose escalation study of GDC-0994 was conducted in patients with locally advanced or metastatic solid tumors. PATIENTS AND METHODS: GDC-0994 was administered once daily on a 21-day on/7-day off schedule to evaluate safety, pharmacokinetics, and preliminary signs of efficacy. Patients with pancreatic adenocarcinoma and BRAF-mutant colorectal cancer were enrolled in the expansion stage. RESULTS: Forty-seven patients were enrolled in six successive cohorts (50-800 mg). A single DLT of grade 3 rash occurred at 600 mg. The most common drug-related adverse events (AE) were diarrhea, rash, nausea, fatigue, and vomiting. Pharmacokinetic data showed dose-proportional increases in exposure, with a mean half-life of 23 hours, supportive of once daily dosing. In evaluable paired biopsies, MAPK pathway inhibition ranged from 19% to 51%. Partial metabolic responses by FDG-PET were observed in 11 of 20 patients across dose levels in multiple tumor types. Overall, 15 of 45 (33%) patients had a best overall response of stable disease and 2 patients with BRAF-mutant colorectal cancer had a confirmed partial response. CONCLUSIONS: GDC-0994 had an acceptable safety profile and pharmacodynamic effects were observed by FDG-PET and in serial tumor biopsies. Single-agent activity was observed in 2 patients with BRAF-mutant colorectal cancer.


MAP Kinase Signaling System/drug effects , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinase 3/antagonists & inhibitors , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/therapeutic use , Pyridones/pharmacokinetics , Pyridones/therapeutic use , Pyrimidines/pharmacokinetics , Pyrimidines/therapeutic use , Adult , Aged , Dose-Response Relationship, Drug , Fatigue/chemically induced , Female , Humans , Male , Maximum Tolerated Dose , Middle Aged , Nausea/chemically induced , Neoplasms/chemically induced , Neoplasms/pathology , Patient Safety , Tissue Distribution , Vomiting/chemically induced
6.
Clin Cancer Res ; 25(22): 6709-6720, 2019 11 15.
Article En | MEDLINE | ID: mdl-31573956

PURPOSE: The success of checkpoint blockade has led to a significant increase in the development of a broad range of immunomodulatory molecules for the treatment of cancer, including agonists against T-cell costimulatory receptors, such as OX40. Unlike checkpoint blockade, where complete and sustained receptor saturation may be required for maximal activity, the optimal dosing regimen and receptor occupancy for agonist agents is less well understood and requires further study. EXPERIMENTAL DESIGN: We integrated both preclinical and clinical biomarker data sets centered on dose, exposure, receptor occupancy, receptor engagement, and downstream pharmacodynamic changes to model the optimal dose and schedule for the OX40 agonist antibody BMS-986178 alone and in combination with checkpoint blockade. RESULTS: Administration of the ligand-blocking anti-mouse surrogate antibody OX40.23 or BMS-986178 as monotherapy or in combination with checkpoint blockade led to increased peripheral CD4+ and CD8+ T-cell activation in tumor-bearing mice and patients with solid tumors, respectively. OX40 receptor occupancy between 20% and 50% both in vitro and in vivo was associated with maximal enhancement of T-cell effector function by anti-OX40 treatment, whereas a receptor occupancy > 40% led to a profound loss in OX40 receptor expression, with clear implications for availability for repeat dosing. CONCLUSIONS: Our results highlight the value of an integrated translational approach applied during early clinical development to aggregate preclinical and clinical data in an effort to define the optimal dose and schedule for T-cell agonists in the clinic.


Antineoplastic Agents, Immunological/therapeutic use , Molecular Targeted Therapy , Neoplasms/drug therapy , Neoplasms/pathology , Receptors, OX40/agonists , Animals , Antineoplastic Agents, Immunological/administration & dosage , Antineoplastic Agents, Immunological/adverse effects , Antineoplastic Agents, Immunological/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , CTLA-4 Antigen/antagonists & inhibitors , Cytokines/metabolism , Disease Models, Animal , Humans , Immunophenotyping , Mice , Mice, Transgenic , Molecular Targeted Therapy/adverse effects , Molecular Targeted Therapy/methods , Neoplasm Metastasis , Neoplasm Staging , Neoplasms/metabolism , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Xenograft Model Antitumor Assays
7.
J Mol Diagn ; 21(6): 1053-1066, 2019 11.
Article En | MEDLINE | ID: mdl-31445211

Microsatellite instability (MSI) is an important biomarker for predicting response to immune checkpoint inhibitor therapy, as emphasized by the recent checkpoint inhibitor approval for MSI-high (MSI-H) solid tumors. Herein, we describe and validate a novel method for determining MSI status from a next-generation sequencing comprehensive genomic profiling assay using formalin-fixed, paraffin-embedded samples. This method is 97% (65/67) concordant with current standards, PCR and immunohistochemistry. We further apply this method to >67,000 patient tumor samples to identify genes and pathways that are enriched in MSI-stable or MSI-H tumor groups. Data show that although rare in tumors other than colorectal and endometrial carcinomas, MSI-H samples are present in many tumor types. Furthermore, the large sample set revealed that MSI-H tumors selectively share alterations in genes across multiple common pathways, including WNT, phosphatidylinositol 3-kinase, and NOTCH. Last, MSI is sufficient, but not necessary, for a tumor to have elevated tumor mutation burden. Therefore, MSI can be determined from comprehensive genomic profiling with high accuracy, allowing for efficient MSI-H detection across all tumor types, especially those in which routine use of immunohistochemistry or PCR-based assays would be impractical because of a rare incidence of MSI. MSI-H tumors are enriched in alterations in specific signaling pathways, providing a rationale for investigating directed immune checkpoint inhibitor therapies in combination with pathway-targeted therapies.


High-Throughput Nucleotide Sequencing/methods , Microsatellite Instability , Neoplasms/genetics , Algorithms , Female , Gene Frequency , High-Throughput Nucleotide Sequencing/statistics & numerical data , Humans , Male , Mutation , Principal Component Analysis
8.
Cancer Res ; 79(15): 3916-3927, 2019 08 01.
Article En | MEDLINE | ID: mdl-31182547

Regulatory T cells (Treg) are immunosuppressive and negatively impact response to cancer immunotherapies. CREB-binding protein (CBP) and p300 are closely related acetyltransferases and transcriptional coactivators. Here, we evaluate the mechanisms by which CBP/p300 regulate Treg differentiation and the consequences of CBP/p300 loss-of-function mutations in follicular lymphoma. Transcriptional and epigenetic profiling identified a cascade of transcription factors essential for Treg differentiation. Mass spectrometry analysis showed that CBP/p300 acetylates prostacyclin synthase, which regulates Treg differentiation by altering proinflammatory cytokine secretion by T and B cells. Reduced Treg presence in tissues harboring CBP/p300 loss-of-function mutations was observed in follicular lymphoma. Our findings provide novel insights into the regulation of Treg differentiation by CBP/p300, with potential clinical implications on alteration of the immune landscape. SIGNIFICANCE: This study provides insights into the dynamic role of CBP/p300 in the differentiation of Tregs, with potential clinical implications in the alteration of the immune landscape in follicular lymphoma.


CREB-Binding Protein/immunology , E1A-Associated p300 Protein/immunology , Lymphoma, Follicular/immunology , T-Lymphocytes, Regulatory/cytology , T-Lymphocytes, Regulatory/immunology , Acetylation , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CREB-Binding Protein/antagonists & inhibitors , CREB-Binding Protein/genetics , Cell Differentiation/physiology , Down-Regulation , E1A-Associated p300 Protein/antagonists & inhibitors , E1A-Associated p300 Protein/genetics , Histones/metabolism , Humans , Lymphoma, Follicular/genetics , Lymphoma, Follicular/metabolism , Lymphoma, Follicular/pathology , Mutation , Pyrazoles/pharmacology , Pyridines/pharmacology , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/metabolism , Transcription, Genetic , Transcriptome
9.
Bioorg Med Chem Lett ; 29(3): 491-495, 2019 02 01.
Article En | MEDLINE | ID: mdl-30553737
10.
NPJ Precis Oncol ; 2(1): 7, 2018.
Article En | MEDLINE | ID: mdl-29872725

KRAS- and BRAF-mutant tumors are often dependent on MAPK signaling for proliferation and survival and thus sensitive to MAPK pathway inhibitors. However, clinical studies have shown that MEK inhibitors are not uniformly effective in these cancers indicating that mutational status of these oncogenes does not accurately capture MAPK pathway activity. A number of transcripts are regulated by this pathway and are recurrently identified in genome-based MAPK transcriptional signatures. To test whether the transcriptional output of only 10 of these targets could quantify MAPK pathway activity with potential predictive or prognostic clinical utility, we created a MAPK Pathway Activity Score (MPAS) derived from aggregated gene expression. In vitro, MPAS predicted sensitivity to MAPK inhibitors in multiple cell lines, comparable to or better than larger genome-based statistical models. Bridging in vitro studies and clinical samples, median MPAS from a given tumor type correlated with cobimetinib (MEK inhibitor) sensitivity of cancer cell lines originating from the same tissue type. Retrospective analyses of clinical datasets showed that MPAS was associated with the sensitivity of melanomas to vemurafenib (HR: 0.596) and negatively prognostic of overall or progression-free survival in both adjuvant and metastatic CRC (HR: 1.5 and 1.4), adrenal cancer (HR: 1.7), and HER2+ breast cancer (HR: 1.6). MPAS thus demonstrates potential clinical utility that warrants further exploration.

12.
PLoS One ; 12(10): e0185862, 2017.
Article En | MEDLINE | ID: mdl-28982154

Mitogen-activated protein kinase (MAPK) pathway dysregulation is implicated in >30% of all cancers, rationalizing the development of RAF, MEK and ERK inhibitors. While BRAF and MEK inhibitors improve BRAF mutant melanoma patient outcomes, these inhibitors had limited success in other MAPK dysregulated tumors, with insufficient pathway suppression and likely pathway reactivation. In this study we show that inhibition of either MEK or ERK alone only transiently inhibits the MAPK pathway due to feedback reactivation. Simultaneous targeting of both MEK and ERK nodes results in deeper and more durable suppression of MAPK signaling that is not achievable with any dose of single agent, in tumors where feedback reactivation occurs. Strikingly, combined MEK and ERK inhibition is synergistic in RAS mutant models but only additive in BRAF mutant models where the RAF complex is dissociated from RAS and thus feedback productivity is disabled. We discovered that pathway reactivation in RAS mutant models occurs at the level of CRAF with combination treatment resulting in a markedly more active pool of CRAF. However, distinct from single node targeting, combining MEK and ERK inhibitor treatment effectively blocks the downstream signaling as assessed by transcriptional signatures and phospho-p90RSK. Importantly, these data reveal that MAPK pathway inhibitors whose activity is attenuated due to feedback reactivation can be rescued with sufficient inhibition by using a combination of MEK and ERK inhibitors. The MEK and ERK combination significantly suppresses MAPK pathway output and tumor growth in vivo to a greater extent than the maximum tolerated doses of single agents, and results in improved anti-tumor activity in multiple xenografts as well as in two Kras mutant genetically engineered mouse (GEM) models. Collectively, these data demonstrate that combined MEK and ERK inhibition is functionally unique, yielding greater than additive anti-tumor effects and elucidates a highly effective combination strategy in MAPK-dependent cancer, such as KRAS mutant tumors.


Extracellular Signal-Regulated MAP Kinases/metabolism , Genes, ras , MAP Kinase Kinase Kinases/metabolism , Neoplasms/enzymology , Blotting, Western , HCT116 Cells , Humans , Neoplasms/genetics , Neoplasms/therapy , Reverse Transcriptase Polymerase Chain Reaction
14.
NPJ Syst Biol Appl ; 3: 14, 2017.
Article En | MEDLINE | ID: mdl-28649441

Approximately 10% of colorectal cancers harbor BRAFV600E mutations, which constitutively activate the MAPK signaling pathway. We sought to determine whether ERK inhibitor (GDC-0994)-containing regimens may be of clinical benefit to these patients based on data from in vitro (cell line) and in vivo (cell- and patient-derived xenograft) studies of cetuximab (EGFR), vemurafenib (BRAF), cobimetinib (MEK), and GDC-0994 (ERK) combinations. Preclinical data was used to develop a mechanism-based computational model linking cell surface receptor (EGFR) activation, the MAPK signaling pathway, and tumor growth. Clinical predictions of anti-tumor activity were enabled by the use of tumor response data from three Phase 1 clinical trials testing combinations of EGFR, BRAF, and MEK inhibitors. Simulated responses to GDC-0994 monotherapy (overall response rate = 17%) accurately predicted results from a Phase 1 clinical trial regarding the number of responding patients (2/18) and the distribution of tumor size changes ("waterfall plot"). Prospective simulations were then used to evaluate potential drug combinations and predictive biomarkers for increasing responsiveness to MEK/ERK inhibitors in these patients.

15.
Mol Cancer Res ; 13(6): 1009-21, 2015 Jun.
Article En | MEDLINE | ID: mdl-25758165

UNLABELLED: Hepatocellular carcinoma (HCC) remains a significant clinical challenge with few therapeutic options available to cancer patients. MicroRNA 21-5p (miR-21) has been shown to be upregulated in HCC, but the contribution of this oncomiR to the maintenance of tumorigenic phenotype in liver cancer remains poorly understood. We have developed potent and specific single-stranded oligonucleotide inhibitors of miR-21 (anti-miRNAs) and used them to interrogate dependency on miR-21 in a panel of liver cancer cell lines. Treatment with anti-miR-21, but not with a mismatch control anti-miRNA, resulted in significant derepression of direct targets of miR-21 and led to loss of viability in the majority of HCC cell lines tested. Robust induction of caspase activity, apoptosis, and necrosis was noted in anti-miR-21-treated HCC cells. Furthermore, ablation of miR-21 activity resulted in inhibition of HCC cell migration and suppression of clonogenic growth. To better understand the consequences of miR-21 suppression, global gene expression profiling was performed on anti-miR-21-treated liver cancer cells, which revealed striking enrichment in miR-21 target genes and deregulation of multiple growth-promoting pathways. Finally, in vivo dependency on miR-21 was observed in two separate HCC tumor xenograft models. In summary, these data establish a clear role for miR-21 in the maintenance of tumorigenic phenotype in HCC in vitro and in vivo. IMPLICATIONS: miR-21 is important for the maintenance of the tumorigenic phenotype of HCC and represents a target for pharmacologic intervention.


Carcinoma, Hepatocellular/metabolism , Cell Proliferation/drug effects , Gene Regulatory Networks/drug effects , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Oligoribonucleotides, Antisense/pharmacology , Animals , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Survival/drug effects , Female , Heterografts , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Mice, Nude , MicroRNAs/antagonists & inhibitors , MicroRNAs/chemistry , Neoplasm Invasiveness , Oligoribonucleotides, Antisense/therapeutic use
16.
J Xray Sci Technol ; 23(1): 25-31, 2015.
Article En | MEDLINE | ID: mdl-25567404

PURPOSE: Segmentation of the left ventricle (LV) in cardiac CT (CCT) images is difficult due to the intensity heterogeneity arising from accumulation of contrast agent in papillary muscle and trabeculae carneae. In this study, we demonstrated the random walks method for LV segmentation in CCT through cardiac phases. METHODS: 63 CCT data sets from 7 patients with 9 cardiac phases were included in this study. All cardiac CT examinations were performed with GE 64-detector CT scanner with ECG gating. In each patient, 60-80 ml iohexol was injected at a flow rate of 5 ml/sec followed by 60 ml normal saline solution. Random walks (RW) based on probability of labels was used for LV segmentation. The LV delineations generated by the experienced physician (MD), conventional image-based method (IB), and RW were compared. RESULTS: In general the contours segment the LV closely by RW and MD, but the discrepancies in papillary muscle and trabeculae carneae were observed while using the IB method. CONCLUSION: We showed the RW method potentially improved LV segmentation as compared to the volume by conventional IB method. In this study, we demonstrated the clinical feasibility of LV volume segmentation using random walks algorithm.


Data Interpretation, Statistical , Heart Ventricles/diagnostic imaging , Pattern Recognition, Automated/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Ventricular Dysfunction, Left/diagnostic imaging , Algorithms , Computer Simulation , Humans , Models, Statistical , Radiographic Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
17.
PLoS One ; 9(12): e114222, 2014.
Article En | MEDLINE | ID: mdl-25536144

OBJECTIVES: Respiration-induced motion in the liver causes potential errors on the measurement of contrast medium in abdominal artery from multiphase hepatic CT scans. In this study, we investigated the use of hepatic CT images to quantitatively estimate the abdominal artery motion due to respiration by optical flow method. MATERIALS AND METHODS: A total of 132 consecutive patients were included in our patient cohort. We apply the optical flow method to compute the motion of the abdominal artery due to respiration. RESULTS: The minimum and maximum displacement of the abdominal artery motion were 0.02 and 30.87 mm by manual delineation, 0.03 and 40.75 mm calculated by optical flow method, respectively. Both high consistency and correlation between the present method and the physicians' manual delineations were acquired with the regression equation of movement, y = 0.81x + 0.25, r = 0.95, p < 0.001. CONCLUSION: We estimated the motion of abdominal artery due to respiration using the optical flow method in multiphase hepatic CT scans and the motion estimations were validated with the visualization of physicians. The quantitative analysis of respiration-related movement of abdominal artery could be used for motion correction in the measurement of contrast medium passing though abdominal artery in multiphase CT liver scans.


Abdomen/blood supply , Arteries/physiology , Artifacts , Liver/diagnostic imaging , Movement , Respiration , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Regression Analysis
18.
Blood ; 124(11): 1777-89, 2014 Sep 11.
Article En | MEDLINE | ID: mdl-25006129

Postchemotherapy relapse presents a major unmet medical need in acute myeloid leukemia (AML), where treatment options are limited. CD25 is a leukemic stem cell marker and a conspicuous prognostic marker for overall/relapse-free survival in AML. Rare occurrence of genetic alterations among PIM family members imposes a substantial hurdle in formulating a compelling patient stratification strategy for the clinical development of selective PIM inhibitors in cancer. Here we show that CD25, a bona fide STAT5 regulated gene, is a mechanistically relevant predictive biomarker for sensitivity to PIM kinase inhibitors. Alone or in combination with tyrosine kinase inhibitors, PIM inhibitors can suppress STAT5 activation and significantly shorten the half-life of MYC to achieve substantial growth inhibition of high CD25-expressing AML cells. Our results highlight the importance of STAT5 and MYC in rendering cancer cells sensitive to PIM inhibitors. Because the presence of a CD25-positive subpopulation in leukemic blasts correlates with poor overall or relapse-free survival, our data suggest that a combination of PIM inhibitors with chemotherapy and tyrosine kinase inhibitors could improve long-term therapeutic outcomes in CD25-positive AML.


Antineoplastic Agents/pharmacology , Blast Crisis , Gene Expression Regulation, Leukemic/drug effects , Interleukin-2 Receptor alpha Subunit/metabolism , Proteolysis/drug effects , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , STAT5 Transcription Factor/metabolism , Antineoplastic Agents/chemistry , Blast Crisis/drug therapy , Blast Crisis/genetics , Blast Crisis/metabolism , Blast Crisis/pathology , Female , HL-60 Cells , Humans , Interleukin-2 Receptor alpha Subunit/genetics , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Leukemia, Myeloid, Acute/pathology , Male , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-pim-1/genetics , Proto-Oncogene Proteins c-pim-1/metabolism , STAT5 Transcription Factor/genetics
19.
Oncotarget ; 5(10): 3362-74, 2014 May 30.
Article En | MEDLINE | ID: mdl-24830942

Inhibitors of JAK2 kinase are emerging as an important treatment modality for myeloproliferative neoplasms (MPN). However, similar to other kinase inhibitors, resistance to JAK2 inhibitors may eventually emerge through a variety of mechanisms. Effective drug combination is one way to enhance therapeutic efficacy and combat resistance against JAK2 inhibitors. To identify potential combination partners for JAK2 compounds in MPN cell lines, we performed pooled shRNA screen targeting 5,000 genes in the presence or absence of JAK2 blockade. One of the top hits identified was MYC, an oncogenic transcription factor that is difficult to inhibit directly, but could be targeted by modulation of upstream regulatory elements such as kinases. We demonstrate herein that PIM kinase inhibitors efficiently suppress MYC protein levels in MPN cell lines. Importantly, overexpression of MYC restores the viability of PIM inhibitor-treated cells, revealing causal relationship between MYC down-regulation and cell growth inhibition by PIM compounds. Combination of various PIM inhibitors with a JAK2 inhibitor results in significant synergistic growth inhibition of multiple MPN cancer cell lines and induction of apoptosis. Mechanistic studies revealed strong downregulation of phosphorylated forms of S6 and 4EBP1 by JAK2/PIM inhibitor combination treatment. Finally, such combination was effective in eradicating in vitro JAK2 inhibitor-resistant MPN clones, where MYC is consistently up-regulated. These findings demonstrate that simultaneous suppression of JAK2 and PIM kinase activity by small molecule inhibitors is more effective than either agent alone in suppressing MPN cell growth. Our data suggest that JAK2 and PIM combination might warrant further investigation for the treatment of JAK2-driven hematologic malignancies.


Antineoplastic Combined Chemotherapy Protocols/pharmacology , Drug Resistance, Neoplasm/drug effects , Janus Kinase 2/antagonists & inhibitors , Myeloproliferative Disorders/enzymology , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Immunoblotting , Protein Kinase Inhibitors/pharmacology
20.
Clin Hemorheol Microcirc ; 58(2): 353-62, 2014.
Article En | MEDLINE | ID: mdl-23370158

Walking can help improve the recovery after stroke. The present study used skin-surface laser-Doppler flowmetry (LDF) measurements and beat-to-beat waveform analysis with the aim of discriminating the microcirculatory blood flow (MBF) characteristics in stroke subjects subdivided into two groups according to their walking ability. Five-minute LDF measurements were performed in the following groups: Group A (cannot walk independently; n = 17), Group B (can walk independently; n = 11), and Group C (healthy controls; n = 17). The pulse width (PW) and foot delay time (FDT) and their coefficients of variation (PWCV and FDTCV, respectively) were calculated for the beat-to-beat LDF waveform. The FDT in Group A and the blood-pressure-normalized PW in Group C were significantly longer than the corresponding values in the other groups, and PWCV and FDTCV were significantly larger in Group C than in Group A. To our knowledge this is the first study demonstrating the feasibility of using a beat-to-beat LDF waveform index to discriminate between stroke subjects with different walking abilities and between stroke and normal subjects. It provides a noninvasive and real-time method for discriminating MBF characteristics, and thus could aid the development of an index for the early detection of stroke or for evaluating the recovery condition in stroke patients.


Blood Flow Velocity/physiology , Laser-Doppler Flowmetry/methods , Aged , Disease Progression , Female , Humans , Male , Stroke
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