The SGK1 Kinase Inhibitor SI113 Sensitizes Theranostic Effects of the 64CuCl2 in Human Glioblastoma Multiforme Cells

Background/Aims: The importance of copper in the metabolism of cancer cells has been widely studied in the last 20 years and a clear-cut association between copper levels and cancer deregulation has been established. Copper-64, emitting positrons and β-radiations, is indicated for the labeling of a large number of molecules suitable for radionuclide imaging as well as radionuclide therapy. Glioblastoma multiforme (GBM) is the CNS tumor with the worse prognosis, characterized by high number of recurrences and strong resistance to chemo-radio therapy, strongly affecting patients survival. We have recently discovered and studied the small molecule SI113, as inhibitor of SGK1, a serine/threonine protein kinase, that affects several neoplastic phenotypes and signaling cascades. The SI113-dependent SGK1 inhibition induces cell death, blocks proliferation, perturbs cell cycle progression and restores chemo-radio sensibility by modulating SGK1-related substrates. In the present paper we aim to characterize the combined effects of 64CuCl2 and SI113 on human GBM cell lines with variable p53 expression. Methods: Cell viability, cell death and stress/authopagic related pathways were then analyzed by FACS and WB-based assays, after exposure to SI113 and/or 64CuCl2. Results: We demonstrate here, that i) 64CuCl2 is able to induce a time and dose dependent modulation of cell viability (with different IC50 values) in highly malignant gliomas and that the co-treatment with SI113 leads to ii) additive/synergistic effects in terms of cell death; iii) enhancement of the effects of ionizing radiations, probably by a TRC1 modulation; iv) modulation of the autophagic response. Conclusions: Evidence reported here underlines the therapeutic potential of the combined treatment with SI113 and 64CuCl2 in GBM cells.

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Chemotherapeutic Effect of SR9009, a REV-ERB Agonist, on the Human Glioblastoma T98G Cells

ASN NEURO ◽

10.1177/1759091419892713 ◽

2019 ◽

Vol 11 ◽

pp. 175909141989271 ◽

Cited By ~ 2

Author(s):

Paula M. Wagner ◽

Natalia M. Monjes ◽

Mario E. Guido

Keyword(s):

Glioblastoma Multiforme ◽

Cell Viability ◽

Circadian Clock ◽

Cell Cycle Progression ◽

Synergistic Effects ◽

Cell Metabolism ◽

Combined Treatment ◽

Chemotherapeutic Agents ◽

Pharmacological Modulation

Glioblastoma multiforme is the most aggressive brain tumor, and human T98G cells constitute a useful glioblastoma multiforme model to evaluate the chemotherapeutic agents. Modern life (shiftwork, jetlag, etc.) may cause circadian disorganization promoting higher cancer risk and metabolic disorders. Although little is known about the tumor-intrinsic circadian clock function, pharmacological modulation of circadian components may offer selective anticancer strategies. REV-ERBs are heme-binding circadian clock components acting as repressors of processes involved in tumorigenesis such as metabolism, proliferation, and inflammation. A synthetic pyrrole derivative (SR9009) that acts as REV-ERBs-specific agonists exhibits potent in vivo activity on metabolism and tumor cell viability. Here, we investigated SR9009 effects on T98G cell viability, differential chemotherapy time responses, and underlying metabolic processes (reactive oxygen species [ROS] and lipid droplets [LDs]) and compared it with the proteasome inhibitor Bortezomib treatment. SR9009-treated cells exhibited significant reduction in cell viability with consequences on cell cycle progression. Dexamethasone synchronized cells displayed differential time responses to SR9009 treatment with highest responses 18 to 30 h after synchronization. SR9009 treatment decreased ROS levels while Bortezomib increased them. However, both treatments significantly increased LD levels, whereas the combined treatment showed additive or synergistic effects between both drugs. In addition, we extended these studies to HepG2 cells which also showed a significant decrease in cell viability and ROS levels and the increase in LD levels after SR9009 treatment. Our results suggest that the pharmacological modulation of the tumor-intrinsic clock by REV-ERB agonists severely affects cell metabolism and promotes cytotoxic effects on cancer cells.

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Combination of Imatinib with Cisplatin and Nutlin-3: Functional and Molecular Effects on Bcr-Abl Positive Cells.

Blood ◽

10.1182/blood.v110.11.2954.2954 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2954-2954

Author(s):

Ioanna Skorta ◽

Heiko van der Kuip ◽

Martin Henkes ◽

Moshe Oren ◽

Walter E. Aulitzky

Keyword(s):

Cell Death ◽

Cell Line ◽

Cellular Response ◽

Combined Treatment ◽

Optimal Growth ◽

Growth Conditions ◽

P53 Expression ◽

Complete Eradication ◽

Abl Kinase ◽

Highly Effective

Abstract Imatinib is highly effective in inducing remissions in chronic phase CML. However, complete eradication of the malignant clone by Imatinib monotherapy is rare. This prompted us to explore the efficacy of combination of Imatinib with the DNA damaging agent Cisplatin and with Nutlin-3, a compound which induces p53 accumulation by interfering with its binding to Mdm2. We used a Bcr-Abl positive cell line characterized by the loss of Imatinib sensitivity in the presence of optimal growth factor concentrations. Whereas combined treatment of Imatinib with either Cisplatin or Nutlin-3 in low and nontoxic doses induced ∼15–20% cell death, simultaneous treatment of all three compounds was highly effective (∼50% cell death) even in the presence of optimal growth conditions. Importantly, comparable effects were also seen in CFU assays performed with primary CD34 positive cells from 5 CML patients. To examine the molecular mechanisms of these effects we analyzed p53 dependent cellular response to Cisplatin in our cell line model in the presence or absence of Imatinib and/or Nutlin-3. The active Bcr-Abl kinase caused superinduction of p53 protein after DNA damage. We found both an upregulated p53 accumulation and enhanced p21 and Mdm2 RNA and protein levels upon Cisplatin treatment. This phenomenon could be reversed both by siRNA-mediated inhibition of Bcr-Abl expression and by Imatinib-induced inhibition of Bcr-Abl kinase activity: despite of optimal growth conditions inhibition of Bcr-Abl caused a significant reduction of p53 expression and activation. In the presence of Nutlin-3, p53 expression was significantly upregulated upon Cisplatin treatment both with and without Imatinib. However, Nutlin-3 was not capable to restore the Imatinib-induced blockade of the transcriptional activity of p53 on mdm2. The reduced p53 activation observed in Bcr-Abl positive cells treated with Imatinib was paralleled by a shift from cell cycle arrest to cell death both in the presence and absence of Nutlin selectively in Bcr-Abl positive cells rendering them hypersensitive to Cisplatin. In summary, combined treatment of Imatinib with low concentrations of a DNA damaging agent and a p53 activator is highly effective in vitro. Such combined treatment may prove to be clinically relevant for complete eradication of the malignant clone in CML, provided that conditions are found where it does not affect adversely normal hematopoietic cells in vivo.

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Combination Of Inhibitors Against DNA Methyltransferases and Histone Deacetylases Synergistically Suppresses Cell Viability In Acute Myeloid Cells In a p53-Dependent Manner

Blood ◽

10.1182/blood.v122.21.4894.4894 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4894-4894 ◽

Cited By ~ 2

Author(s):

Anilkumar Gopalakrishnapillai ◽

Sonali P Barwe ◽

E. Anders Kolb

Keyword(s):

Cell Death ◽

Cell Viability ◽

Dna Methyltransferase ◽

Conflicts Of Interest ◽

Single Agent ◽

Hdac Inhibitors ◽

Dna Methyltransferases ◽

Dependent Manner ◽

P53 Expression ◽

Acute Myeloid

Abstract Acute myeloid leukemia (AML) accounts for 18% of childhood leukemia diagnoses. Although, the 5-year survival rate for children with AML is estimated at 64%, novel therapeutic options are required to improve the outcome for certain subsets of AML that are refractory. The contribution of epigenetic modifiers to the pathogenesis of AML in children is becoming evident following the discovery of mutations in patients, which affect DNA and/or histone methylation. Although DNA methyltransferase (DNMT) inhibitors have been approved in AML, their efficacy as single agents has been limited. This could be due to the crosstalk between DNA methylation and histone modifications that together regulate gene expression. This raises the possibility that optimal re-expression of silenced tumor suppressor genes in AML requires treatment with both DNMT and histone deacetylase (HDAC) inhibitors. We evaluated the effect of a combination of DNA methyltransferase inhibitor azacytidine with HDAC inhibitors panobinostat or romidepsin on the viability of three pediatric AML cell lines- MV4;11 (expressing wild-type p53), THP-1 (with no detectable p53 mRNA) and AML-193 (with mutated p53). We observed that azacytidine as a single-agent only moderately reduced cell viability of MV4;11 cells (IC50 – 7 uM), and it failed to induce cell death in THP-1 and AML-193 cells. However, azacytidine in combination with panobinostat and romidepsin was more effective at reducing cell viability in MV4;11 and THP-1 cells (with a combination index of 0.5 to 0.6). AML-193 cells were almost insensitive to cell death induced by the combination treatment. This suggests that p53 is required for induction of cell death by azacytidine and panobinostat/romidepsin combination. Although THP-1 cells have no detectable p53 expression, other studies have reported the upregulation of p53 following stimulation with nitric oxide or 7-oxysterols. The effect on cell viability in THP-1 cells is likely due to the reexpression of silenced p53 in these cells. Taken together, our data suggests that combining azacytidine with panobinostat/romidepsin induces synergistic cell death in a p53-dependent manner. Disclosures: No relevant conflicts of interest to declare.

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Regulatory elements can be essential for maintaining broad chromatin organization and cell viability

10.1101/2020.12.13.422554 ◽

2020 ◽

Author(s):

Ying Liu ◽

Bo Ding ◽

Lina Zheng ◽

Ping Xu ◽

Zhiheng Liu ◽

...

Keyword(s):

Cell Death ◽

Cell Viability ◽

Cell Survival ◽

Chromatin Structure ◽

Synergistic Effects ◽

Regulatory Elements ◽

Essential Genes ◽

Chromatin Organization ◽

Cellular Functions ◽

3D Chromatin Structure

Increasing evidence shows that promoters and enhancers could be related to 3D chromatin structure, thus affecting cellular functions. Except for functioning through the canonical chromatin loops formed by promoters and enhancers, their roles in maintaining broad chromatin organization have not been well studied. Here, we focused on the active promoters/enhancers (referred to as hotspots) predicted to form many 3D contacts with other active promoters/enhancers, and identified dozens of loci critical for cell survival. While the essentiality of hotspots is not resulted from their association with essential genes, deletion of an essential hotspot could lead to change of broad chromatin organization and expressions of distal genes. We demonstrated that multiple affected genes that are individually non-essential could have synergistic effects to cause cell death.

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Proton Therapy and Src Family Kinase Inhibitor Combined Treatments on U87 Human Glioblastoma Multiforme Cell Line

International Journal of Molecular Sciences ◽

10.3390/ijms20194745 ◽

2019 ◽

Vol 20 (19) ◽

pp. 4745 ◽

Cited By ~ 10

Author(s):

Francesco P Cammarata ◽

Filippo Torrisi ◽

Giusi I Forte ◽

Luigi Minafra ◽

Valentina Bravatà ◽

...

Keyword(s):

Glioblastoma Multiforme ◽

Cell Line ◽

Proton Therapy ◽

Kinase Inhibitor ◽

Malignant Gliomas ◽

Clonogenic Survival ◽

Quadratic Model ◽

Linear Quadratic ◽

Linear Quadratic Model ◽

New Genes

Glioblastoma Multiforme (GBM) is the most common of malignant gliomas in adults with an exiguous life expectancy. Standard treatments are not curative and the resistance to both chemotherapy and conventional radiotherapy (RT) plans is the main cause of GBM care failures. Proton therapy (PT) shows a ballistic precision and a higher dose conformity than conventional RT. In this study we investigated the radiosensitive effects of a new targeted compound, SRC inhibitor, named Si306, in combination with PT on the U87 glioblastoma cell line. Clonogenic survival assay, dose modifying factor calculation and linear-quadratic model were performed to evaluate radiosensitizing effects mediated by combination of the Si306 with PT. Gene expression profiling by microarray was also conducted after PT treatments alone or combined, to identify gene signatures as biomarkers of response to treatments. Our results indicate that the Si306 compound exhibits a radiosensitizing action on the U87 cells causing a synergic cytotoxic effect with PT. In addition, microarray data confirm the SRC role as the main Si306 target and highlights new genes modulated by the combined action of Si306 and PT. We suggest, the Si306 as a new candidate to treat GBM in combination with PT, overcoming resistance to conventional treatments.

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PD-L1 Expression Correlated with p53 Expression in Pediatric Glioblastoma Multiforme

Brain Sciences ◽

10.3390/brainsci11020262 ◽

2021 ◽

Vol 11 (2) ◽

pp. 262

Author(s):

Jakub Litak ◽

Wiesława Grajkowska ◽

Justyna Szumiło ◽

Paweł Krukow ◽

Ryszard Maciejewski ◽

...

Keyword(s):

Glioblastoma Multiforme ◽

Pediatric Population ◽

Malignant Gliomas ◽

Immune Checkpoints ◽

Histopathological Diagnosis ◽

High Grade ◽

P53 Expression ◽

Mortality And Morbidity ◽

Glioblastoma Multiform ◽

Pediatric Glioblastoma

High-grade gliomas are infrequent in the pediatric population compared to adults, nevertheless, mortality and morbidity caused by malignant gliomas in this group of patients remain significant. PD-L1 and PD-1 Immune checkpoints (IC) molecules maintain immunological balance between activation and suppression. Eighteen patients with a histopathological diagnosis of pediatric glioblastoma multiforme (GBM, WHO IV) were studied. In total, PD-L1 expression was detected in 8 patients (44%). The molecular aspect of IC and immunotherapy targeted on PD-1/PD-L1 axis in pediatric population may be a promising adjuvant therapy in pediatric glioblastoma multiform treatment, however, this subject requires further investigation.

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Targeting abundant survivin expression in liposarcoma: subtype dependent therapy responses to YM155 treatment

Journal of Cancer Research and Clinical Oncology ◽

10.1007/s00432-021-03871-5 ◽

2021 ◽

Author(s):

Christian Vay ◽

Philipp M. Schlünder ◽

Levent Dizdar ◽

Irene Esposito ◽

Markus P. H. Ghadimi ◽

...

Keyword(s):

Cell Viability ◽

Therapeutic Potential ◽

Combined Therapy ◽

Combined Treatment ◽

Survivin Expression ◽

Tissue Microarrays ◽

In Vivo Models ◽

The Impact

Abstract Purpose Liposarcoma (LPS) represent the largest group of malignant soft tissue tumours comprising a heterogeneous group of subtypes in which the degrees of chemoresistance and radiosensitivity strongly vary. Consequently, it is of utmost interest to establish novel therapeutic regimens based on molecular targets. Methods Immunohistochemical staining of survivin was performed in tissue microarrays comprising 49 primary LPS specimens. LPS cell lines were treated with survivin antagonist YM155 and doxorubicin or etoposide alone as well as in combination. Changes in cell viability were investigated and the synergistic effect of a combined therapy analysed. Results Immunohistochemistry revealed an abundant expression of survivin in LPS that significantly concurred with less-differentiated tumour subtypes and grading. In vitro, we demonstrated the impact of the survivin inhibitor YM155 on dedifferentiated LPS (DDLPS) and, even more imposing, pleomorphic LPS (PLS) tumour cell viability with a strong induction of apoptosis. A combined treatment of doxorubicin or etoposide with YM155 augmented the cytotoxic effects on DDLPS and PLS cells. Conclusion These findings support the significant role of survivin in the oncogenesis and progression of LPS subtypes providing a rationale to target survivin in eligible in-vivo models and to pioneer clinical applications of survivin-specific substances unfolding their therapeutic potential in LPS patients prospectively.

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Enhancing Radiotherapy Using Ultrasound And Microbubbles With Gold Nanoparticles

10.32920/ryerson.14649744.v1 ◽

2021 ◽

Author(s):

Amanda T.L. Tran

Keyword(s):

Gold Nanoparticles ◽

Cell Death ◽

Radiation Dose ◽

Cell Viability ◽

Therapeutic Effect ◽

Combined Treatment ◽

Genetic Material ◽

Chemotherapeutic Agents ◽

Enhanced Permeability And Retention ◽

Local Radiation

Gold nanoparticles (AuNPs) have been shown to enhance the local radiation dose in tumour mice models. Although AuNPs can be delivered to tumours through enhanced permeability and retention (EPR) effect, delivering of AuNP for therapeutic effect has been proven to be challenging. The application of ultrasound and microbubbles (USMB) has been shown to increase the delivery of genetic material, macromolecules, and chemotherapeutic agents. The hypothesis driving this research is that ultrasound and microbubbles can increase uptake of AuNPs in cells. The results suggest that AuNPs, and USMB aid in its delivery to increase cell death upon irradiation. An improvement of ~ 22 fold was observed with the combined treatment compared to radiation only, implying synergism. In addition, USMB and radiation exhibited an increase in cell death. Cell viability was ~3-4% and is dependent on AuNP concentration, shape and location. Further investigation of this concept was done

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Synergistic Effect of Green Tea Polyphenols on Their Protection Against FK506-Induced Cytotoxicity in Renal Cells

The American Journal of Chinese Medicine ◽

10.1142/s0192415x08006028 ◽

2008 ◽

Vol 36 (03) ◽

pp. 615-624 ◽

Cited By ~ 12

Author(s):

Fumie Hisamura ◽

Akiko Kojima-Yuasa ◽

Xuedan Huang ◽

David Opare Kennedy ◽

Isao Matsui-Yuasa

Keyword(s):

Cell Death ◽

Synergistic Effect ◽

Green Tea ◽

Synergistic Effects ◽

Combined Treatment ◽

Green Tea Extract ◽

Tea Polyphenols ◽

Green Tea Polyphenols ◽

Proximal Tubule Cell ◽

Tea Extract

FK506 (tacrolimus) is a widely used immunosuppressant first employed in the management of rejection in organ transplantation, but now used for autoimmune disease. However, the nephrotoxicity induced by FK506 remains a serious clinical problem. We previously demonstrated that FK506 caused a significant increase in apoptosis of LLC-PK1 cells, a porcine proximal tubule cell line, but the addition of green tea extract and its polyphenolic components suppressed the cell death. Here, we examined the synergistic effect of tea polyphenols on the protection of FK506-induced cell death. The combined treatment with 5 μM (-)-epigallocatechin-gallate (EGCG) and 5 μM of (+)-catechin (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC) or (-)-epicatechin-gallate (ECG) reduced FK506-induced cytotoxicity in LLC-PK1. Similarly, the combined treatment with 5 μM EGC and 5 μM of C, EC, EGCG or ECG also reduced the cytotoxicity. These results showed that the co-treatments with EGCG and EGC, EGCG or ECG, and EGC and ECG have stronger synergistic effects on the protection of FK506-induced cell death. Furthermore, the combined treatment of EGCG (5 μM) and EGC (5 μM) showed a significant time-dependent suppression of the increased intracellular ROS levels 15 min after the addition of FK506, as well as on caspase activation. The results of these synergistic effects of the constituents of green tea extract suggest that its protective effects may reside in more than just one of its constituent.

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Inhibition of autophagy sensitizes gastrointestinal stromal tumor cells to TKI/Bcl-2 inhibitors-induced apoptosis.

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.15_suppl.11036 ◽

2017 ◽

Vol 35 (15_suppl) ◽

pp. 11036-11036

Author(s):

Shuchao Zhang ◽

Guozhi HU ◽

Ana Cristina Paz-Mejia ◽

Luyuan Li ◽

Jonathan C. Trent

Keyword(s):

Western Blot ◽

Cell Viability ◽

Tumor Cells ◽

Cell Apoptosis ◽

Caspase 3 ◽

Kinase Inhibitor ◽

Synergistic Effects ◽

Critical Role ◽

Drug Combinations ◽

Cell Viability Assay

11036 Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of the GI tract. Most GISTs are driven by mutations in KIT or platelet-derived growth factor receptor-α (PDGFRA), which responds well to imatinib, a tyrosine kinase inhibitor (TKI) that blocks KIT and PDGFR-α signaling. Bcl-2 family plays a critical role in the regulation of cell apoptosis in GISTs. ABT-737 as an inhibitor of Bcl-2/Bcl-xL can result in a time and dose-dependent activation of apoptosis. Autophagy is a key mechanism to promote tumor cells survival, inhibition of which can induce the cell death in GISTs. Chloroquine, an antimalarial drug, has been also identified as an autophagy inhibitor. In this study, we assessed the combinational effects of imatinib, ABT-737 and chloroquine in GIST cells. Methods: Human GIST cell lines, GIST-T1 and GIST-882, were employed in our study. Cells were treated with imatinib, ABT-737 and chloroquine either separately or in different combinations. Cell viability was tested by means of MTS and synergistic effects were analyzed by isobologram software. The levels of related proteins of apoptosis (PARP, Caspase-3) and autophagy (LC3-II, beclin-1) were measured by western blot. Cell apoptosis and cell cycle were tested by flow cytometry. Results: Cell viability assay indicated cell survival percentage of double or triple drug combinations ( < 5%) dramatically decreased compared to single drug treatments (42%, 36% or 12%) ( P< 0.05). Isobologram analysis revealed triple drugs combination had stronger synergistic effects than double drugs combinations (CI = 0.204 vs 0.309 or 0.356, P< 0.05). Cell apoptosis percentage of double (32.9% or 36.6%) or triple drugs combinations (66.5%) significantly increased compared to single treatments (6.1%, 6.1% or 13.1%) ( P< 0.05). Western blot showed drugs combinations increased cleavage of PARP and Caspase-3 levels, but inhibited autophagy. Conclusions: The combination of imatinib, ABT-737 and chloroquine has collaborative effects on the treatment of GISTs in vitro. The combined strategy may enhance the clinical efficacy, which provides a rationale for the clinical evaluation of these drug combinations in GISTs treatment.

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