scholarly journals Combined Targeting of AKT and mTOR Inhibits Proliferation of Human NF1-Associated Malignant Peripheral Nerve Sheath Tumour Cells In Vitro but not in a Xenograft Mouse Model In Vivo

2020 ◽  
Vol 21 (4) ◽  
pp. 1548
Author(s):  
Alexander Schulte ◽  
Florian Ewald ◽  
Melanie Spyra ◽  
Daniel J. Smit ◽  
Wei Jiang ◽  
...  
Keyword(s):  
Mouse Model ◽  
Peripheral Nerve ◽  
Cell Lines ◽  
Mapk Pathway ◽  
Synergistic Effects ◽  
Combined Treatment ◽  
Mtor Inhibition ◽  
Nerve Sheath

Persistent signalling via the PI3K/AKT/mTOR pathway is a major driver of malignancy in NF1-associated malignant peripheral nerve sheath tumours (MPNST). Nevertheless, single targeting of this pathway is not sufficient to inhibit MPNST growth. In this report, we demonstrate that combined treatment with the allosteric pan-AKT inhibitor MK-2206 and the mTORC1/mTORC2 inhibitor AZD8055 has synergistic effects on the viability of MPNST cell lines in comparison to the treatment with each compound alone. However, when treating animals bearing experimental MPNST with the combined AKT/mTOR regime, no influence on tumour growth was observed. Further analysis of the MPNST xenograft tumours resistant to AKT/mTOR treatment revealed a reactivation of both AKT and mTOR in several tumour samples. Additional targeting of the RAS/RAF/MEK/MAPK pathway with the allosteric MEK1/2 inhibitor AZD6244 showed synergistic effects on the viability of MPNST cell lines in vitro in comparison to the dual AKT/mTOR inhibition. In summary, these data indicate that combined treatment with AKT and mTOR inhibitors is effective on MPNST cells in vitro but tumour resistance can occur rapidly in vivo by restoration of AKT/mTOR signalling. Our data further suggest that a triple treatment with inhibitors against AKT, mTORC1/2 and MEK1/2 may be a promising treatment option that should be further analysed in an experimental MPNST mouse model in vivo.

scholarly journals DDRE-07. DIPG HARBOUR ALTERATIONS TARGETABLE BY MEK INHIBITORS, WITH ACQUIRED RESISTANCE MECHANISMS OVERCOME BY COMBINATORIAL INHIBITION

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii62-ii62
Author(s):  
Elisa Izquierdo ◽  
Diana Carvalho ◽  
Alan Mackay ◽  
Sara Temelso ◽  
Jessica K R Boult ◽  
...  
Keyword(s):  
Drug Exposure ◽  
Mapk Pathway ◽  
Synergistic Effects ◽  
Acquired Resistance ◽  
Mek Inhibitor ◽  
Resistance Mechanisms ◽  
Genetic Alterations ◽  
Mesenchymal Transition

Abstract The survival of children with diffuse intrinsic pontine glioma (DIPG) remains dismal, with new treatments desperately needed. In the era of precision medicine, targeted therapies represent an exciting treatment opportunity, yet resistance can rapidly emerge, playing an important role in treatment failure. In a prospective biopsy-stratified clinical trial, we combined detailed molecular profiling (methylation BeadArray, exome, RNAseq, phospho-proteomics) linked to drug screening in newly-established patient-derived models of DIPG in vitro and in vivo. We identified a high degree of in vitro sensitivity to the MEK inhibitor trametinib (GI50 16-50nM) in samples, which harboured genetic alterations targeting the MAPK pathway, including the non-canonical BRAF_G469V mutation, and those affecting PIK3R1 and NF1. However, treatment of PDX models and of a patient with trametinib at relapse failed to elicit a significant response. We generated trametinib-resistant clones (62-188-fold, GI50 2.4–5.2µM) in the BRAF_G469V model through continuous drug exposure, and identified acquired mutations in MEK1/2 (MEK1_K57N, MEK1_I141S and MEK2_I115N) with sustained pathway up-regulation. These cells showed the hallmarks of mesenchymal transition, and expression signatures overlapping with inherently trametinib-insensitive primary patient-derived cells that predicted an observed sensitivity to dasatinib. Combinations of trametinib with dasatinib and the downstream ERK inhibitor ulixertinib showed highly synergistic effects in vitro. These data highlight the MAPK pathway as a therapeutic target in DIPG, and show the importance of parallel resistance modelling and rational combinatorial treatments likely to be required for meaningful clinical translation.

scholarly journals Salirasib inhibits the growth of hepatocarcinoma cell lines in vitro and tumor growth in vivo through ras and mTOR inhibition

2010 ◽  
Vol 9 (1) ◽  
pp. 256 ◽  
Author(s):  
Nicolas Charette ◽  
Christine De Saeger ◽  
Valérie Lannoy ◽  
Yves Horsmans ◽  
Isabelle Leclercq ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Cell Lines ◽  
Mtor Inhibition ◽  
Hepatocarcinoma Cell

scholarly journals Radiosensitisation of Hepatocellular Carcinoma Cells by Vandetanib

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1878 ◽  
Author(s):  
Sami Znati ◽  
Rebecca Carter ◽  
Marcos Vasquez ◽  
Adam Westhorpe ◽  
Hassan Shahbakhti ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Combination Therapy ◽  
Cell Lines ◽  
Radiation Treatment ◽  
Combined Treatment ◽  
New Combination ◽  
Migration And Invasion ◽  
Syngeneic Mouse Model

Hepatocellular Carcinoma (HCC) is increasing in incidence worldwide and requires new approaches to therapy. The combination of anti-angiogenic drug therapy and radiotherapy is one promising new approach. The anti-angiogenic drug vandetanib is a tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2 (VEGFR-2) and RET proto-oncogene with radio-enhancement potential. To explore the benefit of combined vandetanib and radiotherapy treatment for HCC, we studied outcomes following combined treatment in pre-clinical models. Methods: Vandetanib and radiation treatment were combined in HCC cell lines grown in vitro and in vivo. In addition to 2D migration and clonogenic assays, the combination was studied in 3D spheroids and a syngeneic mouse model of HCC. Results: Vandetanib IC 50 s were measured in 20 cell lines and the drug was found to significantly enhance radiation cell kill and to inhibit both cell migration and invasion in vitro. In vivo, combination therapy significantly reduced cancer growth and improved overall survival, an effect that persisted for the duration of vandetanib treatment. Conclusion: In 2D and 3D studies in vitro and in a syngeneic model in vivo, the combination of vandetanib plus radiotherapy was more efficacious than either treatment alone. This new combination therapy for HCC merits evaluation in clinical trials.

CDK12 inhibition mediates DNA damage and is synergistic with sorafenib treatment in hepatocellular carcinoma

Gut ◽  
2019 ◽  
Vol 69 (4) ◽  
pp. 727-736 ◽  
Author(s):  
Cun Wang ◽  
Hui Wang ◽  
Cor Lieftink ◽  
Aimee du Chatinier ◽  
Dongmei Gao ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Dna Damage ◽  
Cell Lines ◽  
Synergistic Effects ◽  
Loss Of Function ◽  
Bioinformatics Analyses ◽  
Sorafenib Treatment ◽  
Hcc Cells

ObjectivesHepatocellular carcinoma (HCC) is one of the most frequent malignancies and a major leading cause of cancer-related deaths worldwide. Several therapeutic options like sorafenib and regorafenib provide only modest survival benefit to patients with HCC. This study aims to identify novel druggable candidate genes for patients with HCC.DesignA non-biased CRISPR (clustered regularly interspaced short palindromic repeats) loss-of-function genetic screen targeting all known human kinases was performed to identify vulnerabilities of HCC cells. Whole-transcriptome sequencing (RNA-Seq) and bioinformatics analyses were performed to explore the mechanisms of the action of a cyclin-dependent kinase 12 (CDK12) inhibitor in HCC cells. Multiple in vitro and in vivo assays were used to study the synergistic effects of the combination of CDK12 inhibition and sorafenib.ResultsWe identify CDK12 as critically required for most HCC cell lines. Suppression of CDK12 using short hairpin RNAs (shRNAs) or its inhibition by the covalent small molecule inhibitor THZ531 leads to robust proliferation inhibition. THZ531 preferentially suppresses the expression of DNA repair-related genes and induces strong DNA damage response in HCC cell lines. The combination of THZ531 and sorafenib shows striking synergy by inducing apoptosis or senescence in HCC cells. The synergy between THZ531 and sorafenib may derive from the notion that THZ531 impairs the adaptive responses of HCC cells induced by sorafenib treatment.ConclusionOur data highlight the potential of CDK12 as a drug target for patients with HCC. The striking synergy of THZ531 and sorafenib suggests a potential combination therapy for this difficult to treat cancer.

CHIR258, a Novel Multi-Targeted Tyrosine Kinase Inhibitor, for the Treatment of t(4;14) Multiple Myeloma.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 641-641 ◽  
Author(s):  
Suzanne Trudel ◽  
Zhi Hua Li ◽  
Ellen Wei ◽  
Marion Wiesmann ◽  
Katherine Rendahl ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Mouse Model ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Small Molecule ◽  
Kinase Inhibitor ◽  
Wild Type ◽  
Myeloma Cells

Abstract The t(4;14) translocation that occurs uniquely in a subset (15%) of multiple myeloma (MM) patients results in the ectopic expression of the receptor tyrosine kinase, Fibroblast Growth Factor Receptor3 (FGFR3). Wild-type FGFR3 induces proliferative signals in myeloma cells and appears to be weakly transforming in a hematopoeitic mouse model. The subsequent acquisition of FGFR3 activating mutations in some MM is associated with disease progression and is strongly transforming in several experimental models. The clinical impact of t(4;14) translocations has been demonstrated in several retrospective studies each reporting a marked reduction in overall survival. We have previously shown that inhibition of activated FGFR3 causes morphologic differentiation followed by apoptosis of FGFR3 expressing MM cell lines, validating activated FGFR3 as a therapeutic target in t(4;14) MM and encouraging the clinical development of FGFR3 inhibitors for the treatment of these poor-prognosis patients. CHIR258 is a small molecule kinase inhibitor that targets Class III–V RTKs and inhibits FGFR3 with an IC50 of 5 nM in an in vitro kinase assay. Potent anti-tumor and anti-angiogenic activity has been demonstrated in vitro and in vivo. We employed the IL-6 dependent cell line, B9 that has been engineered to express wild-type FGFR3 or active mutants of FGFR3 (Y373C, K650E, G384D and 807C), to screen CHIR258 for activity against FGFR3. CHIR258 differentially inhibited FGF-mediated growth of B9 expressing wild-type and mutant receptors found in MM, with an IC50 of 25 nM and 80 nM respectively as determined by MTT proliferation assay. Growth of these cells could be rescued by IL-6 demonstrating selectivity of CHIR258 for FGFR3. We then confirmed the activity of CHIR258 against FGFR3 expressing myeloma cells. CHIR258 inhibited the viability of FGFR3 expressing KMS11 (Y373C), KMS18 (G384D) and OPM-2 (K650E) cell lines with an IC50 of 100 nM, 250 nM and 80 nM, respectively. Importantly, inhibition with CHIR258 was still observed in the presence of IL-6, a potent growth factors for MM cells. U266 cells, which lack FGFR3 expression, displayed minimal growth inhibition demonstrating that at effective concentrations, CHIR258 exhibits minimal nonspecific cytotoxicity on MM cells. Further characterization of this finding demonstrated that inhibition of cell growth corresponded to G0/G1 cell cycle arrest and dose-dependent inhibition of downstream ERK phosphorylation. In responsive cell lines, CHIR258 induced apoptosis via caspase 3. In vitro combination analysis of CHIR258 and dexamethasone applied simultaneously to KMS11 cells indicated a synergistic interaction. In vivo studies demonstrated that CHIR258 induced tumor regression and inhibited growth of FGFR3 tumors in a plasmacytoma xenograft mouse model. Finally, CHIR258 produced cytotoxic responses in 4/5 primary myeloma samples derived from patients harboring a t(4;14) translocation. These data indicate that the small molecule inhibitor, CHIR258 potently inhibits FGFR3 and has activity against human MM cells setting the stage for a Phase I clinical trial of this compound in t(4;14) myeloma.

A Phase II Study of PXD101 in Advanced Multiple Myeloma.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3583-3583 ◽  
Author(s):  
Daniel Sullivan ◽  
Seema Singhal ◽  
Michael Schuster ◽  
James Berenson ◽  
Peter Gimsing ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Lines ◽  
Stable Disease ◽  
Progressive Disease ◽  
Synergistic Effects ◽  
Objective Response ◽  
Study Drug ◽  
Primary Objective

Abstract Background: PXD101 is a small molecule HDAC inhibitor of the hydroxamate class, which demonstrates broad anti-neoplastic activity in vitro and in vivo. PXD101 has antiproliferative activity on multiple myeloma cell lines, and shows additive/synergistic effects with standard agents used in myeloma, against these cell lines. PXD101 is being tested as monotherapy and in combination with standard agents for treatment of multiple myeloma. Methods: The primary objective of this study was to assess the activity of PXD101 alone or with dexamethasone, in multiple myeloma patients (pts) who have failed at least 2 prior therapies. Response was measured using the Blade criteria. PXD101 was administered as a 30-min IV infusion on Days 1–5 of a 3-wk cycle, at a dose of 1000 mg/m2/d (900 mg/m2/d in earlier patients). Patients are initially treated with PXD101 alone for two cycles. At the end of cycle two and every cycle thereafter, pts are evaluated for tumor response and continue on the study as follows: pts with objective response or stable disease continue on PXD101 monotherapy, while pts who have progressive disease (PD) are treated with a combination of PXD101 + dexamethasone (Dex). Dex was given orally 40 mg daily on Days 2–5 and 10–13 of the treatment cycle. Results: To date, 24 pts have been enrolled, 19 for which data are currently available. These pts have received a median of 5 (range 2–10) prior therapies. Seventeen pts are evaluable, 12 of whom are evaluable for ≥ 2 cycles, and 5 evaluable for 1 cycle only; 2 pts are unevaluable due to inconsistent baseline that prevented response assessment. Of the 5 pts evaluable for 1 cycle only, 4 discontinued due to PD and one withdrew from study. The 12 pts evaluable for ≥ 2 cycles received a median of 4 treatment cycles (range 2–12); 6 of these patients went on to receive PXD101+Dex. In these 12 pts, duration of PXD101 monotherapy was for 2–4 cycles, with almost all pts (10) receiving only 2 cycles. PXD101+Dex treatment in 6 pts was for 1–10 cycles (10, 6, 4, 4, 3, and 1). In 12 pts on monotherapy for ≥ 2 cycles, there were 6 SD (duration 6–12 wks) and 6 PD. The short duration of SD in PXD101 monotherapy was attributed to patient withdrawal or moving to Dex addition in spite of disease stabilization. All 6 pts receiving PXD101+Dex had previously received at least 2 Dex-containing regimens. One pt had MR (duration 6 wks), and 5 pts had SD. One pt has had SD for 35 wks, with 90% decrease in serum M-component sustained in the last 12 wks; another pt has had SD for 15 wks. In 69 cycles of treatment there were 7 Grade 3/4 adverse events assessed by the investigator as potentially related to study drug. These include anemia (2), infection, respiratory distress, hyperglycemia, thrombocytopenia, and fatigue. Conclusions: PXD101 treatment has resulted in stabilization of advanced and progressive disease, providing clinical benefit to patients. PXD101 combination with dexamethasone led to an MR as well as long duration of stable disease in patients who have previously received multiple Dex regimens. These observations support the continued exploration of PXD101 in combination with other agents for treatment of multiple myeloma.

NR4A3 Suppresses Lymphomagenesis In Vitro and In Vivo by Induction of Similar Patterns of Pro-Apoptotic Genes like NR4A1

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2728-2728
Author(s):  
Alexander JA Deutsch ◽  
Beate Rinner ◽  
Martin Pichler ◽  
Karoline Fechter ◽  
Hildegard T. Greinix ◽  
...  
Keyword(s):  
Mouse Model ◽  
B Cell ◽  
Cell Lines ◽  
Lymphoma Cell ◽  
Receptor Expression ◽  
Aggressive Lymphoma ◽  
Aggressive Lymphomas ◽  
Apoptotic Genes

Abstract The nuclear orphan receptors NR4A1 and NR4A3 have been demonstrated as cooperating tumour suppressor genes leading to rapid development of acute myeloid leukaemia (AML) in double knock-out mice. In humans, their expression is reduced in leukemic blasts in AML patients. Furthermore, NR4A1 and NR4A3 hypoallelic mice develop preleukemic myelodysplastic/myeloproliferative disorders with progression to AML in some cases. Recently we published a comprehensive study of NR4A nuclear receptor expression levels in lymphoid neoplasms that revealed a marked reduction of NR4A1 and NR4A3 in the majority of patients with B-cell chronic lymphocytic leukaemia, with follicular lymphoma, and with diffuse large B cell lymphoma. Interestingly, functional characterization demonstrated that NR4A1 induces apoptosis of aggressive lymphoma cells in vitro and suppresses tumour growth in a xenograft mouse model. Since the role of NR4A3 in aggressive lymphomas is unknown, we aimed to investigate its etiopathogenic function in these tumors. Low expression of NR4A3 was associated with poor survival in aggressive lymphoma patients. Experimentally, induction of NR4A3 expression by inducible ectopic expression in a variety of lymphoma cell lines led to a significantly higher proportion of apoptotic cells as demonstrated by DNA cleavage, Annexin V staining and increased caspase 3/7 activity. To test the tumor suppressor functions of NR4A3 in vivo, the stably transduced SuDHL4-lymphoma cell line was xenografted in the NOD-SCID-gamma (NSG) mouse model. In this system NR4A3 expression abrogated tumor growth in the NSG mice, whereas vector control and uninduced cells formed massive lymphoid tumors. Pharmacological activation of NR4A3 by Thapsigargin and BF175 resulted in a NR4A3 dependent induction of apoptosis in vitro. To dissect differential transcriptional activity of NR4A3 and NR4A1,both factors were separately over-expressed in four different aggressive lymphoma cell lines followed by semi-quantitative mRNA expression analysis of intrinsic and extrinsic apoptotic genes. NR4A1 or NR4A3 over-expression caused apoptosis by induction of BAK, Puma, BIK, BIM, BID and Trail to the same degree. In summary, our data suggest that NR4A3 possesses tumor suppressive function in aggressive lymphomas by pro-apoptotic transactivation and that NR4A3 is functional redundant to NR4A1 in aggressive lymphomas. Disclosures No relevant conflicts of interest to declare.

Looking for synergy or additivity between 188Re and sorafenib on hepatoma cell lines.

2012 ◽  
Vol 30 (4_suppl) ◽  
pp. 247-247
Author(s):  
Marc Pracht ◽  
Nicolas Lepareur ◽  
Julien Edeline ◽  
Laurence Lenoir ◽  
Valerie Ardisson ◽  
...  
Keyword(s):  
Cell Line ◽  
Hepg2 Cell ◽  
Cell Lines ◽  
Hepatoma Cell ◽  
External Beam Radiotherapy ◽  
Combined Treatment ◽  
Hepatoma Cell Lines ◽  
Heparg Cell Line

247 Background: In case of non resectable HCC, radioembolization and sorafenib (S) are therapeutic options respectively for intermediate and advanced stages. In some other cancers, there is an increase of efficacy when external beam radiotherapy is done concomitantly with systemic chemotherapy or targeted therapies. So we wondered if there could be a synergistic or an additive activity when S is combined with a radionuclide. Methods: Hepatoma cell lines N1S1 (murine HCC), HepG2 (human hepatoblastoma) and HepaRG (human HCC) were treated with increasing concentrations of rhenium-188 (188Re) or S. On each cell line, we have studied the cellular toxicities of S and 188Re using Tetrazolium dye test, extra-cellular medium LDH level and morphologic analysis. This was done for different dosage of S and 188Re. We measured the lethal concentration killing 25% of cells (LC25) with the results of the Tetrazolium dye test. Secondly, we looked for synergy or additivity on cellular toxicity of these two compounds according to cell lines by combined treatment. Synergy or additivity was estimated with the combination index (CI) method (synergy if CI lower than 1, additivity if CI = 1, antagonism if CI upper to 1) based on the Tetrazolium dye test’s results. Results: Monotherapy dose-dependent toxicities were observed for all three cell lines with 188Re and for the N1S1 and HepG2 cell lines only with S. Combined treatment with 188Re and S showed synergy on HepaRG and N1S1 cell lines and additivity on the HepG2 cell line. Conclusions: The additive, and even synergistic, interest of a combined treatment with 188Re and S is demonstrated in vitro (for the first time to our knowledge) on hepatoma cell lines. This results, in particular for the HepaRG cell line (human HCC), could be explained by the down-regulation of the hepatic drug transporters which are responsible for the Sorafenib efflux in case of simultaneous DNA damages due to a radionuclide exposition. This promising approach now needs to be confirmed in vivo. [Table: see text]

scholarly journals Effect of Triptolide on Malignant Peripheral Nerve Sheath Tumours In Vitro and In Vivo

2012 ◽  
Vol 40 (6) ◽  
pp. 2284-2294 ◽  
Author(s):  
W Wang ◽  
W Lin ◽  
B Hong ◽  
X Li ◽  
M Zhang ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Nerve Sheath

scholarly journals Combined Treatment with Acalabrutinib and Rapamycin Inhibits Glioma Stem Cells and Promotes Vascular Normalization by Downregulating BTK/mTOR/VEGF Signaling

2021 ◽  
Vol 14 (9) ◽  
pp. 876
Author(s):  
Yu-Kai Su ◽  
Oluwaseun Adebayo Bamodu ◽  
I-Chang Su ◽  
Narpati Wesa Pikatan ◽  
Iat-Hang Fong ◽  
...  
Keyword(s):  
Combined Treatment ◽  
Vascular Normalization ◽  
Mtor Inhibition ◽  
Vitro Assay ◽  
Vegf Signaling ◽  
Xenograft Mice ◽  
Huvec Cells ◽  
Intracellular Signal

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, with a median duration of survival of approximately 14 months after diagnosis. High resistance to chemotherapy remains a major problem. Previously, BTK has been shown to be involved in the intracellular signal transduction including Akt/mTOR signaling and be critical for tumorigenesis. Thus, we aim to evaluate the effect of BTK and mTOR inhibition in GBM. We evaluated the viability of GBM cell lines after treatment with acalabrutinib and/or rapamycin through a SRB staining assay. We then evaluated the effect of both drugs on GBM stem cell-like phenotypes through various in vitro assay. Furthermore, we incubated HUVEC cells with tumorsphere conditioned media and observed their angiogenesis potential, with or without treatment. Finally, we conducted an in vivo study to confirm our in vitro findings and analyzed the effect of this combination on xenograft mice models. Drug combination assay demonstrated a synergistic relationship between acalabrutinib and rapamycin. CSCs phenotypes, including tumorsphere and colony formation with the associated expression of markers of pluripotency are inhibited by either acalabrutinib or rapamycin singly and these effects are enhanced upon combining acalabrutinib and rapamycin. We showed that the angiogenesis capabilities of HUVEC cells are significantly reduced after treatment with acalabrutinib and/or rapamycin. Xenograft tumors treated with both drugs showed significant volume reduction with minimal toxicity. Samples taken from the combined treatment group demonstrated an increased Desmin/CD31 and col IV/vessel ratio, suggesting an increased rate of vascular normalization. Our results demonstrate that BTK-mTOR inhibition disrupts the population of GBM-CSCs and contributes to normalizing GBM vascularization and thus, may serve as a basis for developing therapeutic strategies for chemoresistant/radioresistant GBM.

Sign in / Sign up

Export Citation Format

Share Document