scholarly journals Targeting PDGFRα-activated glioblastoma through specific inhibition of SHP-2–mediated signaling

2019 ◽  
Vol 21 (11) ◽  
pp. 1423-1435 ◽  
Author(s):  
Youzhou Sang ◽  
Yanli Hou ◽  
Rongrong Cheng ◽  
Liang Zheng ◽  
Angel A Alvarez ◽  
...  

Abstract Background Glioblastoma (GBM) is the most malignant primary brain tumor, with dismal median survival. Treatment of GBM is particularly challenging given the intrinsic resistance to chemotherapy and difficulty of drugs to reach the tumor beds due to the blood–brain barrier. Here, we examined the efficacy of SHP099, a potent, selective, and oral SHP-2 inhibitor for treating GBM with activated platelet derived growth factor receptor alpha (PDGFRα) signaling. Methods The effects of SHP099 on cell survival of neural progenitor cells (NPCs), GBM cell lines, and patient-derived glioma stem-like cells (GSCs) were evaluated. Brain and plasma pharmacokinetics of SHP099 and its ability to inhibit SHP-2 signaling were assessed. SHP099 efficacy as a single agent or in combination with temozolomide (TMZ) was assessed using transformed mouse astrocyte and GSC orthotopic xenograft models. Results Activated PDGFRα signaling in established GBM cells, GSCs, and transformed mouse astrocytes was significantly inhibited by SHP099 compared with NPCs in vitro and in vivo through targeting SHP-2–stimulated activation of extracellular signal-regulated protein kinases 1 and 2 in GBM. SHP099 treatment specifically inhibited expression of JUN, a downstream effector of PDGFR signaling, thereby attenuating cell cycle progression in GBM cells with activated PDGFRα. Moreover, SHP099 accumulated at efficacious concentrations in the brain and effectively inhibited orthotopic GBM tumor xenograft growth. SHP099 exhibited antitumor activity either as a single agent or in combination with TMZ and provided significant survival benefits for GBM tumor xenograft-bearing animals. Conclusions Our data demonstrate the utility and feasibility of SHP099 as a potential therapeutic option for improving the clinical treatment of GBM in combination with TMZ.

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Grady L. Nelson ◽  
Conor T. Ronayne ◽  
Lucas N. Solano ◽  
Sravan K. Jonnalagadda ◽  
Shirisha Jonnalagadda ◽  
...  

AbstractNovel silyl cyanocinnamic acid derivatives have been synthesized and evaluated as potential anticancer agents. In vitro studies reveal that lead derivatives 2a and 2b have enhanced cancer cell proliferation inhibition properties when compared to the parent monocarboxylate transporter (MCT) inhibitor cyano-hydroxycinnamic acid (CHC). Further, candidate compounds exhibit several-fold more potent MCT1 inhibition properties as determined by lactate-uptake studies, and these studies are supported by MCT homology modeling and computational inhibitor-docking studies. In vitro effects on glycolysis and mitochondrial metabolism also illustrate that the lead derivatives 2a and 2b lead to significant effects on both metabolic pathways. In vivo systemic toxicity and efficacy studies in colorectal cancer cell WiDr tumor xenograft demonstrate that candidate compounds are well tolerated and exhibit good single agent anticancer efficacy properties.


Author(s):  
Xiaodong Yang ◽  
Anne Steino ◽  
Jeffrey Bacha ◽  
Dennis Brown ◽  
Sabine Mueller

Despite decades of trials, the prognosis for diffuse intrinsic pontine gliomas (DIPG) remains dismal. DIPG is inoperable and standard treatment is radiation alone, as the addition of chemotherapeutic agents, such as temozolomide, have not improved survival. In addition to inherent chemoresistance, treatment of DIPG is impeded by an intact blood-brain barrier (BBB). VAL-083 is a structurally unique bi-functional DNA-targeting agent that readily crosses the BBB. VAL-083 forms interstrand DNA crosslinks at N7-guanine, resulting in DNA double-strand breaks (DSB), S/G2-phase cell-cycle arrest, and ultimately cancer cell death. We have previously demonstrated that VAL-083 is able to overcome temozolomide-resistance in vitro and in vivo, and that its cytotoxicity is independent of the DNA-repair enzyme O6-methylguanine DNA-methyltransferase (MGMT). MGMT is almost universally expressed in DIPG and its expression is strongly correlated with temozolomide-resistance. VAL-083’s distinct mechanism-of-action suggests the potential for combination with inhibitors of DNA DSB repair or S/G2 cell-cycle progression (e.g. Wee1 inhibitor AZD1775). Here, we investigated the effects of VAL-083 in combination with radiation, AZD1775 or irinotecan (topoisomerase inhibitor) in three DIPG cell-lines: SF10693 (H3.1), SF8628 (H3.3) and NEM157 (H3.3). VAL-083 showed activity at low uM-concentration in all three cell-lines. In addition, VAL-083 showed synergy with AZD1775 in all three cell-lines. Combined with its ability to cross the BBB, accumulate in brain tumor tissue and overcome MGMT-related chemoresistance, these results suggest VAL-083 as a potentially attractive treatment option for DIPG as single agent or in combination with AZD1775. Combination studies with radiation are ongoing and will be presented at the meeting.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii6-ii6
Author(s):  
Yuyu He ◽  
Jie Li ◽  
Tomoyuki Koga ◽  
Jun Ma ◽  
Sanjay Dhawan ◽  
...  

Abstract BACKGROUND There are ongoing clinical trials exploring the efficacy of dopamine receptor 2 (DRD2) inhibition against glioblastomas, the most common primary brain tumor. Here we examine potential molecular determinants of this efficacy. METHODS The Cancer Genome Atlas (TCGA) glioblastoma database and other published mRNA profiles were used to analyze the DRD2 and EGFR expression pattern. In vitro and in vivo responses to DRD2 inhibitors were determined using patient derived xenograft (PDX) glioblastoma models. Immunohistochemical studies were performed on clinically annotated glioblastoma samples derived from patients treated with ONC201, a DRD2 inhibitor. RESULTS Analysis of clinical glioblastoma specimens derived from independent patient cohorts revealed an inverse correlation between EGFR and DRD mRNA expression, with implication that signaling mediated by these proteins shares overlapping functions. In independent panels of PDX glioblastoma lines, high EGFR expression was associated with poor in vitro and in vivo response to DRD2 inhibitors, including haloperidol and ONC201. Moreover, ectopic expression of a constitutively active EGFR, EGFRvIII, suppressed glioblastoma sensitivity to ONC201. DRD2 expression positively correlated with expression of rate-limiting enzymes for dopamine synthesis as well as dopamine secretion, suggesting contribution of autocrine DRD2 signaling. Analysis of specimens from patients treated with ONC201 (n = 15) showed an inverse correlation between the intensity of EGFR staining and clinical response. The median overall survival for patients with high and low EGFR staining was 162 and 373 days, respectively (p = 0.037). CONCLUSIONS High EGFR expression is a determinant of poor glioblastoma response to DRD2. This finding should inform future clinical trial designs.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Lucas N. Solano ◽  
Grady L. Nelson ◽  
Conor T. Ronayne ◽  
Shirisha Jonnalagadda ◽  
Sravan K. Jonnalagadda ◽  
...  

Abstract Novel N-phenylindazole based diarylureas have been designed, synthesized and evaluated as potential anticancer agents. In vitro cell viability studies of these derivatives illustrate good potency with IC50 values in the range of 0.4–50 μM in several cancer cell lines including murine metastatic breast cancer 4T1, murine glioblastoma GL261, human triple negative breast cancer MDA-MB-231, human pancreatic cancer MIAPaCa-2, and human colorectal cancer cell line WiDr. The ester group in the lead compound 8i was modified to incorporate amino-amides to increase solubility and stability while retaining biological activity. Further in vitro studies reveal that lead candidates inhibit tube length in HUVEC cells. In vivo systemic toxicity studies indicate that these candidate compounds are well tolerated in mice without any significant side effects. Anticancer efficacy studies in WiDr tumor xenograft and 4T1 tumor syngraft models demonstrate that the lead candidate 11 exhibits significant antitumor properties as a single agent in these tumor models.


2020 ◽  
Author(s):  
Ioannis Pozios ◽  
Nina N. Seel ◽  
Nina A. Hering ◽  
Lisa Hartmann ◽  
Verena Liu ◽  
...  

Abstract Purpose Currently, the exact role of estrogen receptor (ER) signaling in pancreatic cancer is unknown. Recently, we showed that expression of phosphorylated ERβ correlates with a poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC). Here, we hypothesized that raloxifene, a FDA-approved selective ER modulator (SERM), may suppress PDAC tumor growth by interfering with ERβ signaling. To test this hypothesis, we studied the impact of raloxifene on interleukin-6/glycoprotein-130/signal transducer and activator of transcription-3 (IL-6/gp130/STAT3) signaling. Methods Human PDAC cell lines were exposed to raloxifene after which growth inhibition was assessed using a BrdU assay. ER knockdown was performed using siRNAs specific for ERα and ERβ. The effects of raloxifene on IL-6 expression and STAT3 phosphorylation in PDAC cells were assessed by ELISA and Western blotting, respectively. In addition, raloxifene was administered to an orthotopic PDAC tumor xenograft mouse model, after which tumor growth was monitored and immunohistochemistry was performed. Results Raloxifene inhibited the in vitro growth of PDAC cells, and this effect was reversed by siRNA-mediated knockdown of ERβ, but not of ERα, indicating ER isotype-specific signaling. We also found that treatment with raloxifene inhibited the release of IL-6 and suppressed the phosphorylation of STAT3Y705 in PDAC cells. In vivo, we found that orthotopic PDAC tumor growth, lymph node and liver metastases as well as Ki-67 expression were reduced in mice treated with raloxifene. Conclusions Inhibition of ERβ and the IL-6/gp130/STAT3 signaling pathway by raloxifene leads to potent reduction of PDAC growth in vitro and in vivo. Our results suggest that ERβ signaling and IL-6/gp130 interaction may serve as promising drug targets for pancreatic cancer and that raloxifene may serve as an attractive therapeutic option for PDAC patients expressing the ERβ isotype.


Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1713
Author(s):  
Elodie Pramil ◽  
Clémentine Dillard ◽  
Alexandre E. Escargueil

Immunotherapy is a very promising field of research and application for treating cancers, in particular for those that are resistant to chemotherapeutics. Immunotherapy aims at enhancing immune cell activation to increase tumor cells recognition and killing. However, some specific cancer types, such as colorectal cancer (CRC), are less responsive than others to the current immunotherapies. Intrinsic resistance can be mediated by the development of an immuno-suppressive environment in CRC. The mutational status of cancer cells also plays a role in this process. CRC can indeed be distinguished in two main subtypes. Microsatellite instable (MSI) tumors show a hyper-mutable phenotype caused by the deficiency of the DNA mismatch repair machinery (MMR) while microsatellite stable (MSS) tumors show a comparatively more “stable” mutational phenotype. Several studies demonstrated that MSI CRC generally display good prognoses for patients and immunotherapy is considered as a therapeutic option for this type of tumors. On the contrary, MSS metastatic CRC usually presents a worse prognosis and is not responsive to immunotherapy. According to this, developing new and innovative models for studying CRC response towards immune targeted therapies has become essential in the last years. Herein, we review the in vitro and in vivo models used for research in the field of immunotherapy applied to colorectal cancer.


2021 ◽  
Author(s):  
Shuxin Xiao ◽  
Chuanbo Fan ◽  
Jinlong Ma ◽  
Hongwei Xue ◽  
Liqin Xu

STAT3 is a transcription factor and a candidate therapeutic option for human cancers. However, the underlying mechanism of STAT3 in the pathogenesis of diffuse large B-cell lymphoma (DLBCL) has yet to be established. We studied here whether STAT3 contributes to CCL4 transcription elevation in DLBCL. Our established protein-protein interactions (PPI) network revealed the overexpression of STAT3 and CCL4 in DLBCL. Mechanistically, STAT3 activated CCL4 transcription to induce the Wnt/β-catenin pathway. The prognostic analysis exhibited that the overall survival of patients with high STAT3 and CCL4 were poorer than those with low STAT3 and CCL4 expression. In addition, silencing of STAT3 reverted the malignant phenotype in DLBCL cells. CCL4 overexpression partly weakened the si-STAT3-mediated anti-tumor effects on DLBCL cells. Tumor xenograft models showed that si-STAT3 inhibited tumor growth in vivo and decreased proliferative and mitogenic activities in tumor tissues, findings that were consistent with the in vitro data. Hence, this study provides new evidence that STAT3 and CCL4 may be new prognostic biomarkers and therapeutic targets for treating DLBCL.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi34-vi35
Author(s):  
Mylan Blomquist ◽  
Teresa Noviello ◽  
Fulvio D'Angelo ◽  
Christopher Sereduk ◽  
Benjamin Rabichow ◽  
...  

Abstract Glioblastoma (GBM), the most common primary brain tumor in adults, remains uniformly fatal due to the lack of effective targeted therapies for this aggressive malignancy. Genomic amplification of epidermal growth factor receptor (EGFR) occurs in 40-60% of primary GBM. Half of all EGFR-amplified cases of GBM also harbor EGFRvIII, a constitutively active, truncated variant of EGFR. The incidence of EGFR alterations in GBM makes inhibition of EGFR/EGFRvIII an attractive therapeutic approach. Depatuxizumab mafodotin (ABT-414) is an antibody-drug conjugate comprised of ABT-806, a mAB against EGFR, and a cytotoxic payload (monomethyl auristatin F). ABT-414 therapy initially showed promising results as an EGFRvIII therapy in vivo and in vitro; however, ABT414 failed to provide a survival benefit in phase I/II clinical trials, potentially due to therapeutic resistance. In this study, we seek to investigate the mechanisms of resistance to ABT-414 by performing whole exome, transcriptome and single cell RNA seq on ABT-414 resistant GBM PDX tumors. Our data showed an enrichment of mutations unique to the ABT-414 resistant tumors, including a point mutation (S466I) in TEK/TIE2 transmembrane angiopoietin receptor. In vitro expression of TEK S466I in GBM cells showed an increase in activation of ERK and STAT3 and increased TEK/TIE2 immunoprecipitation with EGFR compared to the wild-type TEK receptor. Furthermore, gene ontology analysis reveals that ABT-414-treated flank tumors exhibit increased activation of extracellular matrix organization and CNS developmental processes compared to flank tumors in the control treatment groups. ABT-414-treated tumors also demonstrate increased expression of inhibitor of differentiation (ID)1 and ID3, associated with stem-like phenotype in glioblastoma. Taken together, our data indicate that resistance to ABT-414 is mediated by both de novo mutations not detected in the parent tumor and adaptive dysregulation of pathways which may lead to dedifferentiation and therapeutic resistance.


2020 ◽  
Author(s):  
Giulia Cristinziano ◽  
Manuela Porru ◽  
Dante Lamberti ◽  
Simonetta Buglioni ◽  
Francesca Rollo ◽  
...  

AbstractBackground and aimsAbout 15% of intrahepatic cholangiocarcinoma (iCCA) express fibroblast growth factor receptor 2 (FGFR2) fusion proteins (FFs), most often in concert with mutationally inactivated TP53, CDKN2A or BAP1. FFs span residues 1-768 of FGFR2 fused to sequences encoded by any of a long list (>60) of partner genes, a configuration sufficient to ignite oncogenic FF activation. In line, FGFR-specific tyrosine kinase inhibitors (F-TKI) were shown to provide clinical benefit in FF+ iCCA, although responses were partial and/or limited by resistance mechanisms, including the FF V565F gatekeeper mutation. Herein we present an FF-driven murine iCCA model and exploit its potential for pre-clinical studies on FF therapeutic targeting.MethodsFour iCCA FFs carrying different fusion sequences were expressed in Tp53-/- mouse liver organoids. Tumorigenic properties of genetically modified liver organoids were assessed by intrahepatic/subcutaneous transplantation in immuno-deficient mice. Cellular models derived from neoplastic lesions were exploited for pre-clinical studies.ResultsTumors diagnosed as CCA were obtained upon transplantation of FF-expressing liver organoids. The penetrance of this tumorigenic phenotype was influenced by FF identity. Tumor organoids and 2D cell lines derived from CCA lesions were addicted to FF signaling via Ras-Erk, regardless of FF identity or presence of V565F mutation. Double blockade of FF-Ras-Erk pathway by concomitant pharmacological inhibition of FFs and Mek1/2 provided greater therapeutic efficacy than single agent F-TKI in vitro and in vivo.ConclusionsFF-driven iCCA pathogenesis was successfully modelled in murine Tp53-/- background. This model revealed biological heterogeneity among structurally different FFs. Double blockade of FF-Erk signaling deserves consideration for improving precision-based approaches against human FF+ iCCA.


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