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1.
New Phytol ; 243(3): 1123-1136, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38831656

ABSTRACT

Plant secreted peptides RAPID ALKALINISATION FACTORs (RALFs), which act through the receptor FERONIA (FER), play important roles in plant growth. However, it remains unclear whether and how RALF-FER contributes to the trade-off of plant growth-defense. Here, we used a variety of techniques such as CRISPR/Cas9, protein-protein interaction and transcriptional regulation methods to investigate the role of RALF2 and its receptor FER in regulating lignin deposition, root growth, and defense against Fusarium oxysporum f. sp. lycopersici (Fol) in tomato (Solanum lycopersicum). The ralf2 and fer mutants show reduced primary root length, elevated lignin accumulation, and enhanced resistance against Fol than the wild-type. FER interacts with and phosphorylates MYB63 to promote its degradation. MYB63 serves as an activator of lignin deposition by regulating the transcription of dirigent protein gene DIR19. Mutation of DIR19 suppresses lignin accumulation, and reverses the short root phenotype and Fol resistance in ralf2 or fer mutant. Collectively, our results demonstrate that the RALF2-FER-MYB63 module fine-tunes root growth and resistance against Fol through regulating the deposition of lignin in tomato roots. The study sheds new light on how plants maintain the growth-defense balance via RALF-FER.


Subject(s)
Fusarium , Gene Expression Regulation, Plant , Lignin , Mutation , Plant Proteins , Plant Roots , Solanum lycopersicum , Solanum lycopersicum/genetics , Solanum lycopersicum/growth & development , Solanum lycopersicum/metabolism , Solanum lycopersicum/microbiology , Plant Proteins/metabolism , Plant Proteins/genetics , Plant Roots/metabolism , Plant Roots/growth & development , Lignin/metabolism , Fusarium/physiology , Mutation/genetics , Disease Resistance/genetics , Transcription Factors/metabolism , Transcription Factors/genetics , Plant Diseases/microbiology , Phosphorylation
2.
Mol Plant ; 17(4): 598-613, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38341757

ABSTRACT

Jasmonates (JAs), a class of lipid-derived stress hormones, play a crucial role across an array of plant physiological processes and stress responses. Although JA signaling is thought to rely predominantly on the degradation of specific JAZ proteins by SCFCOI1, it remains unclear whether other pathways are involved in the regulation of JAZ protein stability. Here, we report that PUB22, a plant U-box type E3 ubiquitin ligase, plays a critical role in the regulation of plant resistance against Helicoverpa armigera and other JA responses in tomato. Whereas COI1 physically interacts with JAZ1/2/5/7, PUB22 physically interacts with JAZ1/3/4/6. PUB22 ubiquitinates JAZ4 to promote its degradation via the 26S proteasome pathway. Importantly, we observed that pub22 mutants showreduced resistance to H. armigera, whereas jaz4 single mutants and jaz1 jaz3 jaz4 jaz6 quadruple mutants have enhanced resistance. The hypersensitivity of pub22 mutants to herbivores could be partially rescued by JAZ4 mutation. Moreover, we found that expression of PUB22 can be transcriptionally activated by MYC2, thus forming a positive feedback circuit in JA signaling. We noticed that the PUB22-JAZ4 module also regulates other JA responses, including defense against B. cinerea, inhibition of root elongation, and anthocyanin accumulation. Taken together, these results indicate that PUB22 plays a crucial role in plant growth and defense responses, together with COI1-regulated JA signaling, by targeting specific JAZs.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Solanum lycopersicum , Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Repressor Proteins/metabolism , Solanum lycopersicum/genetics , Cyclopentanes/metabolism , Oxylipins/metabolism , Plants/metabolism , Gene Expression Regulation, Plant , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Ubiquitin-Protein Ligases/metabolism
3.
Neurooncol Adv ; 6(1): vdad165, 2024.
Article in English | MEDLINE | ID: mdl-38213834

ABSTRACT

Background: The most prevalent cancer treatments cause cell death through DNA damage. However, DNA damage response (DDR) repair pathways, initiated by tumor cells, can withstand the effects of anticancer drugs, providing justification for combining DDR inhibitors with DNA-damaging anticancer treatments. Methods: Cell viability assays were performed with CellTiter-Glo assay. DNA damage was evaluated using Western blotting analysis. RNA-seq and single-cell level expression were used to identify the DDR signatures. In vivo, studies were conducted in mice to determine the effect of ATris on TMZ sensitization. Results: We found a subpopulation of glioma sphere-forming cells (GSCs) with substantial synergism with temozolomide (TMZ) using a panel of 3 clinical-grade ataxia-telangiectasia- and Rad3-related kinase inhibitors (ATRis), (elimusertib, berzosertib, and ceralasertib). Interestingly, most synergistic cell lines had O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation, indicating that ATRi mainly benefits tumors with no MGMT repair. Further, TMZ activated the ATR-checkpoint kinase 1 (Chk1) axis in an MGMT-dependent way. TMZ caused ATR-dependent Chk1 phosphorylation and DNA double-strand breaks as shown by increased γH2AX. Increased DNA damage and decreased Chk1 phosphorylation were observed upon the addition of ATRis to TMZ in MGMT-methylated (MGMT-) GSCs. TMZ also improved sensitivity to ATRis in vivo, as shown by increased mouse survival with the TMZ and ATRi combination treatment. Conclusions: This research provides a rationale for selectively targeting MGMT-methylated cells using ATRis and TMZ combination. Overall, we believe that MGMT methylation status in GBM could serve as a robust biomarker for patient selection for ATRi combined with TMZ.

4.
Plant Cell Environ ; 47(4): 1334-1347, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38221812

ABSTRACT

Cold stress is a major meteorological threat to crop growth and yield. Abscisic acid (ABA) plays important roles in plant cold tolerance by activating the expression of cold-responsive genes; however, the underlying transcriptional regulatory module remains unknown. Here, we demonstrated that the cold- and ABA-responsive transcription factor ETHYLENE RESPONSE FACTOR 15 (ERF15) positively regulates ABA-mediated cold tolerance in tomato. Exogenous ABA treatment significantly enhanced cold tolerance in wild-type tomato plants but failed to rescue erf15 mutants from cold stress. Transcriptome analysis showed that ERF15 was associated with the expression of cold-responsive transcription factors such as CBF1 and WRKY6. Further RT-qPCR assays confirmed that the ABA-induced increased in CBF1 and WRKY6 transcripts was suppressed in erf15 mutants when the plants were subjected to cold treatment. Moreover, yeast one-hybrid assays, dual-luciferase assays and electrophoretic mobility shift assays demonstrated that ERF15 activated the transcription of CBF1 and WRKY6 by binding their promoters. Silencing CBF1 or WRKY6 significantly decreased cold tolerance. Overall, our study identified the role of ERF15 in conferring ABA-mediated cold tolerance in tomato plants by activating CBF1 and WRKY6 expression. This study not only broadens our knowledge of the mechanism of ABA-mediated cold tolerance in plants but also highlights ERF15 as an ideal target gene for cold-tolerant crop breeding.


Subject(s)
Abscisic Acid , Solanum lycopersicum , Abscisic Acid/pharmacology , Abscisic Acid/metabolism , Solanum lycopersicum/genetics , Gene Expression Regulation, Plant , Transcription Factors/genetics , Transcription Factors/metabolism , Ethylenes , Plant Proteins/genetics , Plant Proteins/metabolism , Cold Temperature , Plants, Genetically Modified/metabolism
5.
Planta ; 257(1): 26, 2022 Dec 26.
Article in English | MEDLINE | ID: mdl-36571656

ABSTRACT

MAIN CONCLUSION: 495 bZIP members with 12 subfamilies were identified in the five diploid cottons. Segmental duplication events in cotton ancestor might have led to primary expansion of the cotton bZIP members. The basic leucine zipper (bZIP) transcription factor is one of the largest and most diverse families in plants. The evolutionary history of the bZIP family is still unclear in cotton. In this study, a total of 495 bZIP members were identified in five diploid Gossypium species, including 100 members in Gossypium arboreum, 104 members in Gossypium herbaceum, 95 members in Gossypium raimondii, 96 members in Gossypium longicalyx, and 100 members in Gossypium turneri. The bZIP members could be divided into 12 subfamilies with biased gene proportions, gene structures, conserved motifs, expansion rates, gene loss rates, and cis-regulatory elements. A total of 239 duplication events were identified in the five Gossypium species, and mainly occurred in their common ancestor. Furthermore, some GabZIPs and GhebZIPs could be regarded as important candidates in cotton breeding. The bZIP members had a conserved and divergent evolution in the five diploid Gossypium species. The current study laid an important foundation on the evolutionary history of the bZIP family in cotton.


Subject(s)
Basic-Leucine Zipper Transcription Factors , Gossypium , Gossypium/genetics , Basic-Leucine Zipper Transcription Factors/genetics , Multigene Family , Diploidy , Plant Breeding , Phylogeny , Gene Expression Regulation, Plant/genetics , Genome, Plant , Plant Proteins/genetics
6.
J Ovarian Res ; 15(1): 113, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36243865

ABSTRACT

BACKGROUND: Ovarian cancer is a common cause of death among women and a health problem worldwide. Circ_0000144 has been confirmed to be an oncogene involved in cancer progression, such as gastric cancer. However, the role of circ_0000144 in ovarian cancer remains unclear and needs to be elucidated. This retrospective study aimed to investigate the underlying mechanism of circ_0000144 in ovarian cancer. METHODS: Differentially expressed circ_0000144 expression in ovarian cancer and normal tissues was identified by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). In vitro assays were performed to explore the biological functions of circ_0000144 in ovarian cancer cells. An in vivo xenograft model was used to investigate the efficacy of circ_0000144 in the progression of ovarian cancer. RESULTS: Circ_0000144 was significantly upregulated in ovarian cancer cells and tissues. Circ_0000144 overexpression significantly promoted ovarian cancer cell proliferation, migration, and invasion. This study further demonstrated that circ_0000144 downregulated ELK3 levels by sponging miR-610 in ovarian cancer cells. Moreover, circ_0000144 significantly promotes ovarian cancer tumorigenesis in vivo. CONCLUSION: Our data indicate that circ_0000144 could enhance the carcinogenesis of ovarian cancer by specifically targeting miR-610, which may serve as a novel target for the diagnosis and prognosis of ovarian cancer.


Subject(s)
MicroRNAs , Ovarian Neoplasms , Carcinogenesis/genetics , Carcinoma, Ovarian Epithelial/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/metabolism , Ovarian Neoplasms/genetics , Proto-Oncogene Proteins c-ets/genetics , Proto-Oncogene Proteins c-ets/metabolism , RNA, Circular/genetics , Retrospective Studies
7.
New Phytol ; 236(5): 1796-1808, 2022 12.
Article in English | MEDLINE | ID: mdl-36052744

ABSTRACT

Herbivory severely affects plant growth, posing a threat to crop production. Calcium ion (Ca2+ ) signaling and accumulation of jasmonates (JAs) are activated in plant response to herbivore attack, leading to the expression of defense pathways. However, little is known about how the Ca2+ signal modulates JA biosynthesis. We used diverse techniques, including CRISPR/Cas9, UPLC-MS/MS and molecular biology methods to explore the role of ETHYLENE RESPONSE FACTOR 16 in Ca2+ signal-triggered JA burst during herbivore defense in tomato. Here we show that simulated herbivory induces GLUTAMATE RECEPTOR LIKE3.3/3.5 (GLR3.3/3.5)-dependent increases in electrical activity, Ca2+ influx and increases the abundance of CALMODULIN2 (CaM2) and ERF16 transcripts in tomato. The interaction between CaM2 and ERF16 promotes JA biosynthesis by enhancing the transcriptional activity of ERF16, which increases the activation of ERF16 expression and causes expression of LIPOXYGENASE D (LOXD), AOC and 12-OXO-PHYTODIENOIC ACID REDUCTASE 3 (OPR3), the key genes in JA biosynthesis. Mutation of CaM2 results in decreased JA accumulation, together with the expression of JA biosynthesis-related genes, leading to reduced resistance to the cotton bollworm Helicoverpa armigera. These findings reveal a molecular mechanism underpinning the Ca2+ signal-initiated systemic JA burst and emphasize the pivotal role of Ca2+ signal/ERF16 crosstalk in herbivore defense.


Subject(s)
Moths , Solanum lycopersicum , Animals , Herbivory/physiology , Solanum lycopersicum/metabolism , Chromatography, Liquid , Tandem Mass Spectrometry , Oxylipins/metabolism , Cyclopentanes/metabolism , Gene Expression Regulation, Plant
8.
Antioxidants (Basel) ; 10(11)2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34829692

ABSTRACT

Fruits are excellent sources of essential vitamins and health-boosting minerals. Recently, regulation of fruit ripening by both internal and external cues for the improvement of fruit quality and shelf life has received considerable attention. Rosmarinic acid (RA) is a kind of natural plant-derived polyphenol, widely used in the drug therapy and food industry due to its distinct physiological functions. However, the role of RA in plant growth and development, especially at the postharvest period of fruits, remains largely unknown. Here, we demonstrated that postharvest RA treatment delayed the ripening in tomato fruits. Exogenous application of RA decreased ripening-associated ethylene production and inhibited the fruit color change from green to red based on the decline in lycopene accumulation. We also found that the degradation of sucrose and malic acid during ripening was significantly suppressed in RA-treated tomato fruits. The results of metabolite profiling showed that RA application promoted the accumulation of multiple amino acids in tomato fruits, such as aspartic acid, serine, tyrosine, and proline. Meanwhile, RA application also strengthened the antioxidant system by increasing both the activity of antioxidant enzymes and the contents of reduced forms of antioxidants. These findings not only unveiled a novel function of RA in fruit ripening, but also indicated an attractive strategy to manage and improve shelf life, flavor, and sensory evolution of tomato fruits.

9.
Neuro Oncol ; 23(6): 920-931, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33433610

ABSTRACT

BACKGROUND: Temozolomide (TMZ) resistance in glioblastoma multiforme (GBM) is mediated by the DNA repair protein O6-methylguanine DNA methyltransferase (MGMT). MGMT promoter methylation (occurs in about 40% of patients) is associated with loss of MGMT expression (MGMT-) that compromises DNA repair, leading to a favorable response to TMZ therapy. The 60% of patients with unmethylated MGMT (MGMT+) GBM experience resistance to TMZ; in these patients, understanding the mechanism of MGMT-mediated repair and modulating MGMT activity may lead to enhanced TMZ activity. Here, we report a novel mode of regulation of MGMT protein activity by poly(ADP-ribose) polymerase (PARP). METHODS: MGMT-PARP interaction was detected by co-immunoprecipitation. PARylation of MGMT and PARP was detected by co-immunoprecipitation with anti-PAR antibody. O6-methylguanine (O6-MetG) adducts were quantified by immunofluorescence assay. In vivo studies were conducted in mice to determine the effectiveness of PARP inhibition in sensitizing GBM to TMZ. RESULTS: We demonstrated that PARP physically binds with MGMT and PARylates MGMT in response to TMZ treatment. In addition, PARylation of MGMT by PARP is required for MGMT binding to chromatin to enhance the removal of O6-MetG adducts from DNA after TMZ treatment. PARP inhibitors reduced PARP-MGMT binding and MGMT PARylation, silencing MGMT activity to repair O6-MetG. PARP inhibition restored TMZ sensitivity in vivo in MGMT-expressing GBM. CONCLUSION: This study demonstrated that PARylation of MGMT by PARP is critical for repairing TMZ-induced O6-MetG, and inhibition of PARylation by PARP inhibitor reduces MGMT function rendering sensitization to TMZ, providing a rationale for combining PARP inhibitors to sensitize TMZ in MGMT-unmethylated GBM.


Subject(s)
Glioblastoma , Animals , Antineoplastic Agents, Alkylating/pharmacology , Antineoplastic Agents, Alkylating/therapeutic use , Cell Line, Tumor , DNA Damage , DNA Modification Methylases/genetics , DNA Modification Methylases/metabolism , DNA Repair Enzymes/genetics , DNA Repair Enzymes/metabolism , Dacarbazine/pharmacology , Dacarbazine/therapeutic use , Glioblastoma/drug therapy , Glioblastoma/genetics , Guanine/analogs & derivatives , Humans , Mice , Poly ADP Ribosylation , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Temozolomide/pharmacology , Temozolomide/therapeutic use , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
10.
Nat Commun ; 12(1): 139, 2021 01 08.
Article in English | MEDLINE | ID: mdl-33420056

ABSTRACT

Active telomerase is essential for stem cells and most cancers to maintain telomeres. The enzymatic activity of telomerase is related but not equivalent to the expression of TERT, the catalytic subunit of the complex. Here we show that telomerase enzymatic activity can be robustly estimated from the expression of a 13-gene signature. We demonstrate the validity of the expression-based approach, named EXTEND, using cell lines, cancer samples, and non-neoplastic samples. When applied to over 9,000 tumors and single cells, we find a strong correlation between telomerase activity and cancer stemness. This correlation is largely driven by a small population of proliferating cancer cells that exhibits both high telomerase activity and cancer stemness. This study establishes a computational framework for quantifying telomerase enzymatic activity and provides new insights into the relationships among telomerase, cancer proliferation, and stemness.


Subject(s)
Computational Biology/methods , Gene Expression Regulation, Neoplastic , Neoplasms/genetics , Telomerase/metabolism , Algorithms , Cell Cycle/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Datasets as Topic , Enzyme Assays , Humans , Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Promoter Regions, Genetic , RNA-Seq , Single-Cell Analysis , Telomere Homeostasis , Exome Sequencing
11.
Clin Cancer Res ; 26(6): 1395-1407, 2020 03 15.
Article in English | MEDLINE | ID: mdl-31852834

ABSTRACT

PURPOSE: Exploration of novel strategies to extend the benefit of PARP inhibitors beyond BRCA-mutant cancers is of great interest in personalized medicine. Here, we identified EGFR amplification as a potential biomarker to predict sensitivity to PARP inhibition, providing selection for the glioblastoma (GBM) patient population who will benefit from PARP inhibition therapy. EXPERIMENTAL DESIGN: Selective sensitivity to the PARP inhibitor talazoparib was screened and validated in two sets [test set (n = 14) and validation set (n = 13)] of well-characterized patient-derived glioma sphere-forming cells (GSC). FISH was used to detect EGFR copy number. DNA damage response following talazoparib treatment was evaluated by γH2AX and 53BP1 staining and neutral comet assay. PARP-DNA trapping was analyzed by subcellular fractionation. The selective monotherapy of talazoparib was confirmed using in vivo glioma models. RESULTS: EGFR-amplified GSCs showed remarkable sensitivity to talazoparib treatment. EGFR amplification was associated with increased reactive oxygen species (ROS) and subsequent increased basal expression of DNA-repair pathways to counterelevated oxidative stress, and thus rendered vulnerability to PARP inhibition. Following talazoparib treatment, EGFR-amplified GSCs showed enhanced DNA damage and increased PARP-DNA trapping, which augmented the cytotoxicity. EGFR amplification-associated selective sensitivity was further supported by the in vivo experimental results showing that talazoparib significantly suppressed tumor growth in EGFR-amplified subcutaneous models but not in nonamplified models. CONCLUSIONS: EGFR-amplified cells are highly sensitive to talazoparib. Our data provide insight into the potential of using EGFR amplification as a selection biomarker for the development of personalized therapy.


Subject(s)
Brain Neoplasms/drug therapy , DNA Damage , Gene Amplification , Glioblastoma/drug therapy , Oxidative Stress , Phthalazines/pharmacology , Animals , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Line, Tumor , ErbB Receptors/genetics , Glioblastoma/genetics , Glioblastoma/pathology , Humans , Male , Mice , Mice, Nude , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Spheroids, Cellular , Xenograft Model Antitumor Assays
12.
Am J Cancer Res ; 9(11): 2428-2441, 2019.
Article in English | MEDLINE | ID: mdl-31815044

ABSTRACT

Glioblastoma multiforme (GBM), the most common type of primary brain tumor, is universally fatal, with a median survival duration ranging from 12-15 months despite maximum treatment efforts. Temozolomide (TMZ) is the current standard of care for GBM patients; however patients usually develop resistance to TMZ and limits its benefit. The identification of novel synergistic targets in GBM will lead to the development of new targeted drugs, which could be combined with broad-spectrum cytotoxic agents. In this study, we used a high-throughput synthetic lethality screen with a pooled short hairpin DNA repair library, in combination with TMZ, to identify targets that will enhance TMZ-induced antitumor effects. Using an unbiased bioinformatical analysis, we identified BRCA1 as a potential promising candidate gene that induced synthetic lethality with TMZ in glioma sphere-forming cells (GSCs). BRCA1 knockdown resulted in antitumor activity with TMZ in P53 wild-type GSCs but not in P53 mutant GSCs. TMZ treatment induced a DNA damage repair response; the activation of BRCA1 DNA repair pathway targets and knockdown of BRCA1, together with TMZ, led to increased DNA damage and cell death in P53 wild-type GSCs. Our study identified BRCA1 as a potential target that sensitizes TMZ-induced cell death in P53 wild-type GBM, suggesting that the combined inhibition of BRCA1 and TMZ treatment will be a successful targeted therapy for GBM patients.

13.
Am J Cancer Res ; 9(8): 1734-1745, 2019.
Article in English | MEDLINE | ID: mdl-31497354

ABSTRACT

Glioblastoma (GBM) is the most common and lethal primary intracranial tumor. Aggressive surgical resection plus radiotherapy and temozolomide have prolonged patients' median survival to only 14.6 months. Therefore, there is a critical need to develop novel therapeutic strategies for GBM. In this study, we evaluated the effect of NOTCH signaling intervention by gamma-secretase inhibitors (GSIs) on glioma sphere-forming cells (GSCs). GSI sensitivity exhibited remarkable selectivity among wild-type TP53 (wt-p53) GSCs. GSIs significantly impaired the sphere formation of GSCs harboring wt-p53. We also identified a concurrence between GSI sensitivity, NOTCH1 expression, and wt-p53 activity in GSCs. Through a series of gene editing and drug treatment experiments, we found that wt-p53 did not modulate NOTCH1 pathway, whereas NOTCH1 signaling positively regulated wt-p53 expression and activity in GSCs. Finally, GSIs (targeting NOTCH signaling) synergized with doxorubicin (activating wt-p53) to inhibit proliferation and induce apoptosis in wt-p53 GSCs. Taken together, we identified wt-p53 as a potential marker for GSI sensitivity in GSCs. Combining GSI with doxorubicin synergistically inhibited the proliferation and survival of GSCs harboring wt-p53.

14.
Cancer Res ; 79(19): 5088-5101, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31416846

ABSTRACT

PI3K-targeting therapy represents one of the most sought-after therapies for glioblastoma (GBM). Several small-molecule inhibitors have been evaluated in clinical trials, however, the emergence of resistance limits treatment potential. Here, we generated a patient-derived glioma sphere-forming cell (GSC) xenograft model resistant to the PI3K-specific inhibitor BKM-120. Integrated RNA sequencing and high-throughput drug screening revealed that the Aurora A kinase (Aurora A)/Polo-like kinase 1 (PLK1)/cyclin-dependent kinase 1 (CDK1) signaling pathway was the main driver of PI3K inhibitor resistance in the resistant xenografts. Aurora kinase was upregulated and pCDK1 was downregulated in resistant tumors from both xenografts and tumor tissues from patients treated with the PI3K inhibitor. Mechanistically, the tyrosine kinase receptor Tie2 physically interacted with FGFR1, promoting STAT3 phosphorylation and binding to the AURKA promoter, which increased Aurora A expression in resistant GSCs. Concurrent inhibition of Aurora A and PI3K signaling overcame PI3K inhibitor-induced resistance. This study offers a proof of concept to target PI3K and the collateral-activated pathway to improve GBM therapy. SIGNIFICANCE: These findings provide novel insights into the mechanisms of PI3K inhibitor resistance in glioblastoma.


Subject(s)
Drug Resistance, Neoplasm/physiology , Glioblastoma/pathology , Signal Transduction/physiology , Animals , Aurora Kinase A/metabolism , CDC2 Protein Kinase/metabolism , Cell Cycle Proteins/metabolism , Heterografts , Humans , Male , Mice , Mice, Nude , Phosphatidylinositol 3-Kinases/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Receptor, Fibroblast Growth Factor, Type 1/metabolism , Receptor, TIE-2/metabolism , Up-Regulation , Polo-Like Kinase 1
15.
ISA Trans ; 92: 155-165, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31056215

ABSTRACT

This paper proposes a higher-order sliding mode observer based robust backstepping control to realize high-performance sensorless speed regulation for the interior permanent magnet synchronous motor (IPMSM). A new robust adaptive super-twisting higher-order sliding mode based observer is proposed to estimate the rotor position. The proposed observer has advantages of sliding chattering reduction and robustness against uncertainties. And, a new robust integral adaptive backstepping control with sliding mode actions is designed to achieve precise speed regulation. The uncertainties with unknown bounds can be stabilized by the sliding mode actions. And both transient and steady performance can be achieved by using the sliding mode and integral actions simultaneously. Then, a sensorless scheme is put forward to by combining the presented observer and the proposed controller. The stability of the observer and controller are verified. Simulation and experiment results validate the proposed approach.

16.
J Clin Oncol ; 37(9): 741-750, 2019 03 20.
Article in English | MEDLINE | ID: mdl-30715997

ABSTRACT

PURPOSE: Phosphatidylinositol 3-kinase (PI3K) signaling is highly active in glioblastomas. We assessed pharmacokinetics, pharmacodynamics, and efficacy of the pan-PI3K inhibitor buparlisib in patients with recurrent glioblastoma with PI3K pathway activation. METHODS: This study was a multicenter, open-label, multi-arm, phase II trial in patients with PI3K pathway-activated glioblastoma at first or second recurrence. In cohort 1, patients scheduled for re-operation after progression received buparlisib for 7 to 13 days before surgery to evaluate brain penetration and modulation of the PI3K pathway in resected tumor tissue. In cohort 2, patients not eligible for re-operation received buparlisib until progression or unacceptable toxicity. Once daily oral buparlisib 100 mg was administered on a continuous 28-day schedule. Primary end points were PI3K pathway inhibition in tumor tissue and buparlisib pharmacokinetics in cohort 1 and 6-month progression-free survival (PFS6) in cohort 2. RESULTS: Sixty-five patients were treated (cohort 1, n = 15; cohort 2, n = 50). In cohort 1, reduction of phosphorylated AKTS473 immunohistochemistry score was achieved in six (42.8%) of 14 patients, but effects on phosphoribosomal protein S6S235/236 and proliferation were not significant. Tumor-to-plasma drug level was 1.0. In cohort 2, four (8%) of 50 patients reached 6-month PFS6, and the median PFS was 1.7 months (95% CI, 1.4 to 1.8 months). The most common grade 3 or greater adverse events related to treatment were lipase elevation (n = 7 [10.8%]), fatigue (n = 4 [6.2%]), hyperglycemia (n = 3 [4.6%]), and elevated ALT (n = 3 [4.6%]). CONCLUSION: Buparlisib had minimal single-agent efficacy in patients with PI3K-activated recurrent glioblastoma. Although buparlisib achieved significant brain penetration, the lack of clinical efficacy was explained by incomplete blockade of the PI3K pathway in tumor tissue. Integrative results suggest that additional study of PI3K inhibitors that achieve more-complete pathway inhibition may still be warranted.


Subject(s)
Aminopyridines/therapeutic use , Antineoplastic Agents/therapeutic use , Brain Neoplasms/drug therapy , Glioblastoma/drug therapy , Morpholines/therapeutic use , Neoadjuvant Therapy , Neoplasm Recurrence, Local , Phosphatidylinositol 3-Kinase/metabolism , Phosphoinositide-3 Kinase Inhibitors/therapeutic use , Adult , Aged , Aged, 80 and over , Aminopyridines/adverse effects , Aminopyridines/pharmacokinetics , Antineoplastic Agents/adverse effects , Brain Neoplasms/enzymology , Brain Neoplasms/pathology , Chemotherapy, Adjuvant , Disease Progression , Enzyme Activation , Female , Glioblastoma/enzymology , Glioblastoma/pathology , Humans , Male , Middle Aged , Morpholines/adverse effects , Morpholines/pharmacokinetics , Neoadjuvant Therapy/adverse effects , Phosphoinositide-3 Kinase Inhibitors/adverse effects , Phosphoinositide-3 Kinase Inhibitors/pharmacokinetics , Progression-Free Survival , Time Factors
17.
J Mol Neurosci ; 65(3): 359-366, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29936663

ABSTRACT

Ischemic stroke (IS) is the main cause of mortality and disability in China; thus, this study aimed to examine the association between six variants and their haplotypes within the transferrin (TF) gene and the risk of IS in the Southern Chinese Han population. Genotyping was performed using the Sequenom MassARRAY platform for 249 IS patients and 249 age- and sex-matched controls. The association between polymorphisms and IS risk was tested by Chi squared test and haplotype and stratification analysis. Odds ratios (ORs) and confidence intervals (CIs) were estimated by unconditional logistic regression analysis. The results of genetic model analyses indicated that the two SNPs (rs1880669 and rs2692695) were associated with decreased IS risk under the co-dominant, dominant, and additive models. Additionally, rs4525863 was also associated with decreased IS risk both under the dominant and additive models in males. Moreover, the CG haplotype of TF (rs1880669 and rs2692695) was significantly associated with a decreased risk of IS in the total population and males. Our findings suggested that polymorphisms (rs4525863, rs1880669, and rs2692695) of the TF gene might be a protective factor for IS in Southern Chinese Han population. Further large prospective studies are required to confirm these findings.


Subject(s)
Brain Ischemia/genetics , Polymorphism, Single Nucleotide , Stroke/genetics , Transferrin/genetics , Aged , Case-Control Studies , China , Female , Humans , Male , Middle Aged
18.
Medicine (Baltimore) ; 97(22): e10836, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29851791

ABSTRACT

RATIONALE: Ulcerative skin tuberculosis (TB) is a rare form of extrapulmonary TB. CASE REPORT: We present a case of a 65-year-old patient with perianal ulcer, which had been present for 1 year. Anamnesis revealed he had been persistently coughing for the same period of time. Histological examination of perianal skin showed necrotizing granulomatous lesions, acid-fast staining in sputum samples was ++++, TB antibody in the blood was positive, TB DNA test was positive, and chest scan that showed secondary pulmonary TB accompanied by possible pulmonary cavity formation in the 2 upper lungs. INTERVENTIONS: Anti-TB therapy with isoniazid, rifampicin, ethambutol, and pyrazinamide for 6 months. The skin ulcer completely healed after 6 months. CONCLUSION: TB should be suspected for nonhealing ulcers. Pertinent studies should be done early during the lesion; finally, TB treatment should be initiated immediately after diagnosis is made.


Subject(s)
Fissure in Ano/pathology , Tuberculosis, Cutaneous/pathology , Tuberculosis, Pulmonary/diagnostic imaging , Aged , Antitubercular Agents/therapeutic use , Ethambutol/administration & dosage , Ethambutol/therapeutic use , Fissure in Ano/drug therapy , Fissure in Ano/microbiology , Humans , Isoniazid/administration & dosage , Isoniazid/therapeutic use , Male , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Pyrazinamide/administration & dosage , Pyrazinamide/therapeutic use , Rifampin/administration & dosage , Rifampin/therapeutic use , Sputum/immunology , Tomography, X-Ray Computed/methods , Treatment Outcome , Tuberculosis, Cutaneous/drug therapy , Tuberculosis, Cutaneous/microbiology , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/pathology
19.
Oncotarget ; 9(12): 10497-10509, 2018 Feb 13.
Article in English | MEDLINE | ID: mdl-29535822

ABSTRACT

BACKGROUND: Despite the availability of hundreds of cancer drugs, there is insufficient data on the efficacy of these drugs on the extremely heterogeneous tumor cell populations of glioblastoma (GBM). RESULTS: The PKIS of 357 compounds was initially evaluated in 15 different GSC lines which then led to a more focused screening of the 21 most highly active compounds in 11 unique GSC lines using HTS screening for cell viability. We further validated the HTS result with the second-generation PLK1 inhibitor volasertib as a single agent and in combination with ionizing radiation (IR). In vitro studies showed that volasertib inhibited cell viability, and high levels of the anti-apoptotic protein Bcl-xL expression were highly correlated with volasertib resistance. Volasertib sensitized GSCs to radiation therapy by enhancing G2/M arrest and by inducing apoptosis. Colony-formation assay demonstrated that volasertib plus IR synergistically inhibited colony formation. In intracranial xenograft mouse models, the combination of volasertib and radiation significantly inhibited GSC tumor growth and prolonged median survival compared with radiation treatment alone due to inhibition of cell proliferation, enhancement of DNA damage, and induction of apoptosis. CONCLUSIONS: Our results reinforce the potential therapeutic efficacy of volasertib in combination with radiation for the treatment of GBM. METHODS: We used high-throughput screening (HTS) to identify drugs, out of 357 compounds in the published Protein Kinase Inhibitor Set, with the greatest efficacy against a panel of glioma stem cells (GSCs), which are representative of the classic cancer genome atlas (TCGA) molecular subtypes.

20.
Neuro Oncol ; 20(1): 78-91, 2018 01 10.
Article in English | MEDLINE | ID: mdl-29016926

ABSTRACT

Background: Oncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM. Methods: Patient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes. Results: PI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration. Conclusions: Our findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.


Subject(s)
Brain Neoplasms/metabolism , Cell Cycle Proteins/metabolism , Glioblastoma/metabolism , Nuclear Proteins/metabolism , Phosphoinositide-3 Kinase Inhibitors , Protein-Tyrosine Kinases/metabolism , Animals , Apoptosis/drug effects , Brain Neoplasms/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Enzyme Inhibitors/therapeutic use , Glioblastoma/drug therapy , Humans , Mice, Nude , Phosphorylation , Tumor Suppressor Protein p53/metabolism
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