Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 33
Filter
1.
J Nucl Med ; 65(1): 100-108, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38050111

ABSTRACT

The overexpression of fibroblast activation protein-α (FAP) in solid cancers relative to levels in normal tissues has led to its recognition as a target for delivering agents directly to tumors. Radiolabeled quinoline-based FAP ligands have established clinical feasibility for tumor imaging, but their therapeutic potential is limited due to suboptimal tumor retention, which has prompted the search for alternative pharmacophores. One such pharmacophore is the boronic acid derivative N-(pyridine-4-carbonyl)-d-Ala-boroPro, a potent and selective FAP inhibitor (FAPI). In this study, the diagnostic and therapeutic (theranostic) potential of N-(pyridine-4-carbonyl)-d-Ala-boroPro-based metal-chelating DOTA-FAPIs was evaluated. Methods: Three DOTA-FAPIs, PNT6555, PNT6952, and PNT6522, were synthesized and characterized with respect to potency and selectivity toward soluble and cell membrane FAP; cellular uptake of the Lu-chelated analogs; biodistribution and pharmacokinetics in mice xenografted with human embryonic kidney cell-derived tumors expressing mouse FAP; the diagnostic potential of 68Ga-chelated DOTA-FAPIs by direct organ assay and small-animal PET; the antitumor activity of 177Lu-, 225Ac-, or 161Tb-chelated analogs using human embryonic kidney cell-derived tumors expressing mouse FAP; and the tumor-selective delivery of 177Lu-chelated DOTA-FAPIs via direct organ assay and SPECT. Results: DOTA-FAPIs and their natGa and natLu chelates exhibited potent inhibition of human and mouse sources of FAP and greatly reduced activity toward closely related prolyl endopeptidase and dipeptidyl peptidase 4. 68Ga-PNT6555 and 68Ga-PNT6952 showed rapid renal clearance and continuous accumulation in tumors, resulting in tumor-selective exposure at 60 min after administration. 177Lu-PNT6555 was distinguished from 177Lu-PNT6952 and 177Lu-PNT6522 by significantly higher tumor accumulation over 168 h. In therapeutic studies, all 3 177Lu-DOTA-FAPIs exhibited significant antitumor activity at well-tolerated doses, with 177Lu-PNT6555 producing the greatest tumor growth delay and animal survival. 225Ac-PNT6555 and 161Tb-PNT6555 were similarly efficacious, producing 80% and 100% survival at optimal doses, respectively. Conclusion: PNT6555 has potential for clinical translation as a theranostic agent in FAP-positive cancer.


Subject(s)
Gallium Radioisotopes , Positron-Emission Tomography , Humans , Animals , Mice , Tissue Distribution , Cell Line, Tumor , Pyridines
2.
Clin Cancer Res ; 29(4): 791-804, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36441800

ABSTRACT

PURPOSE: Leukemia inhibitory factor (LIF) is a multifunctional cytokine with numerous reported roles in cancer and is thought to drive tumor development and progression. Characterization of LIF and clinical-stage LIF inhibitors would increase our understanding of LIF as a therapeutic target. EXPERIMENTAL DESIGN: We first tested the association of LIF expression with transcript signatures representing multiple processes regulating tumor development and progression. Next, we developed MSC-1, a high-affinity therapeutic antibody that potently inhibits LIF signaling and tested it in immune competent animal models of cancer. RESULTS: LIF was associated with signatures of tumor-associated macrophages (TAM) across 7,769 tumor samples spanning 22 solid tumor indications. In human tumors, LIF receptor was highly expressed within the macrophage compartment and LIF treatment drove macrophages to acquire immunosuppressive capacity. MSC-1 potently inhibited LIF signaling by binding an epitope that overlaps with the gp130 receptor binding site on LIF. MSC-1 showed monotherapy efficacy in vivo and drove TAMs to acquire antitumor and proinflammatory function in syngeneic colon cancer mouse models. Combining MSC-1 with anti-PD1 leads to strong antitumor response and a long-term tumor-free survival in a significant proportion of treated mice. CONCLUSIONS: Overall, our findings highlight LIF as a therapeutic target for cancer immunotherapy.


Subject(s)
Neoplasms , Tumor Microenvironment , Animals , Humans , Mice , Immunosuppression Therapy , Leukemia Inhibitory Factor/genetics , Leukemia Inhibitory Factor/metabolism , Macrophages/metabolism , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/metabolism , Tumor Microenvironment/genetics
3.
Mol Cancer Res ; 20(6): 895-908, 2022 06 03.
Article in English | MEDLINE | ID: mdl-35190818

ABSTRACT

Survival for high-risk neuroblastoma remains poor. Most patients who recur, present with metastatic disease, and few targetable pathways that govern spread to distant sites are currently known. We previously developed a metastatic mouse model to select cells with enhanced ability to spread to the bone and brain and identified a signature based on differentially expressed genes, which also predicted patient survival. To discover new neuroblastoma therapies, we utilized the Connectivity Map to identify compounds that can reverse this metastatic transcriptional signature and found calcipotriol, a vitamin D3 analog, to be a compound that selectively targets cell lines with enhanced metastatic potential. Calcipotriol treatment of enhanced metastatic, but not parental, cells reduces proliferation and survival via vitamin D receptor (VDR) signaling, increases the expression of RASSF2, a negative regulator of the Hippo signaling pathway, and reduces the levels of the Hippo pathway effectors YAP and TAZ. RASSF2 is required for the effects of calcipotriol and for the reduction of levels and nuclear localization of YAP/TAZ. Migration of the enhanced metastatic cells and YAP/TAZ levels are reduced after calcipotriol treatment and YAP overexpression reduces calcipotriol sensitivity. Furthermore, metastatic cells that overexpress VDR also showed lower tumor burden in vivo. IMPLICATIONS: This newly identified link between VDR signaling and the Hippo pathway could inform treatment strategies for metastatic neuroblastoma.


Subject(s)
Neuroblastoma , Protein Serine-Threonine Kinases , Animals , Cell Survival , Hippo Signaling Pathway , Humans , Mice , Neoplasm Recurrence, Local , Neuroblastoma/drug therapy , Neuroblastoma/genetics , Phosphoproteins/genetics , Protein Serine-Threonine Kinases/genetics , Receptors, Calcitriol/genetics , Receptors, Calcitriol/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , YAP-Signaling Proteins
4.
Nat Commun ; 11(1): 4323, 2020 08 28.
Article in English | MEDLINE | ID: mdl-32859895

ABSTRACT

Medulloblastoma (MB) is defined by four molecular subgroups (Wnt, Shh, Group 3, Group 4) with Wnt MB having the most favorable prognosis. Since prior reports have illustrated the antitumorigenic role of Wnt activation in Shh MB, we aimed to assess the effects of activated canonical Wnt signaling in Group 3 and 4 MBs. By using primary patient-derived MB brain tumor-initiating cell (BTIC) lines, we characterize differences in the tumor-initiating capacity of Wnt, Group 3, and Group 4 MB. With single cell RNA-seq technology, we demonstrate the presence of rare Wnt-active cells in non-Wnt MBs, which functionally retain the impaired tumorigenic potential of Wnt MB. In treating MB xenografts with a Wnt agonist, we provide a rational therapeutic option in which the protective effects of Wnt-driven MBs may be augmented in Group 3 and 4 MB and thereby support emerging data for a context-dependent tumor suppressive role for Wnt/ß-catenin signaling.


Subject(s)
Cerebellar Neoplasms/therapy , Medulloblastoma/therapy , Wnt Proteins/pharmacology , Wnt Proteins/therapeutic use , Animals , Carcinogenesis , Cell Line, Tumor , Cell Proliferation , Cerebellar Neoplasms/pathology , Disease Models, Animal , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Heterografts , Humans , Medulloblastoma/genetics , Medulloblastoma/pathology , Mice , Stem Cells , Wnt Proteins/genetics , Wnt Signaling Pathway , beta Catenin/therapeutic use
5.
Cell Mol Biol Lett ; 24: 59, 2019.
Article in English | MEDLINE | ID: mdl-31754354

ABSTRACT

BACKGROUND: Breast tumor growth and recurrence are driven by an infrequent population of breast tumor-initiating cells (BTIC). We and others have reported that the frequency of BTIC is orders of magnitude higher when breast tumor cells are propagated in vitro as clonal spheres, termed tumorspheres, by comparison to adherent cells. We exploited the latter to screen > 35,000 small molecules to identify agents capable of targeting BTIC. We unexpectedly discovered that selective antagonists of serotonin signaling were among the hit compounds. To better understand the relationship between serotonin and BTIC we expanded our analysis to include monoamine oxidase-A (MAO-A), an enzyme that metabolizes serotonin. METHODS: We used the Nanostring technology and Western blotting to determine whether MAO-A is expressed in human breast tumor cell lines cultured as tumorspheres by comparison to those grown as adherent cells. We then determined whether MAO-A activity is required for tumorsphere formation, a surrogate in vitro assay for BTIC, by assessing whether selective MAO-A inhibitors affect the frequency of tumorsphere-forming cells. To learn whether MAO-A expression in breast tumor cells is associated with other reported properties of BTIC such as anticancer drug resistance or breast tumor recurrence, we performed differential gene expression analyses using publicly available transcriptomic datasets. RESULTS: Tumorspheres derived from human breast tumor cell lines representative of every breast cancer clinical subtype displayed increased expression of MAO-A transcripts and protein by comparison to adherent cells. Surprisingly, inhibition of MAO-A activity with selective inhibitors reduced the frequency of tumorsphere-forming cells. We also found that increased MAO-A expression is a common feature of human breast tumor cell lines that have acquired anticancer drug resistance and is associated with poor recurrence-free survival (RFS) in patients that experienced high-grade, ER-negative (ER-) breast tumors. CONCLUSIONS: Our data suggests that MAO-A activity is required for tumorsphere formation and that its expression in breast tumor cells is associated with BTIC-related properties. The discovery that a selective MAO-A inhibitor targets tumorsphere-forming cells with potencies in the nanomolar range provides the first evidence of this agent's anticancer property. These data warrant further investigation of the link between MAO-A and BTIC.


Subject(s)
Breast Neoplasms/metabolism , Monoamine Oxidase/metabolism , Neoplastic Stem Cells/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Humans , Monoamine Oxidase/analysis , Monoamine Oxidase/genetics , Neoplastic Stem Cells/pathology , Serotonin/metabolism
6.
Oncogene ; 38(10): 1702-1716, 2019 03.
Article in English | MEDLINE | ID: mdl-30348991

ABSTRACT

Medulloblastoma (MB) is the most frequent malignant pediatric brain tumor, representing 20% of newly diagnosed childhood central nervous system malignancies. Although advances in multimodal therapy yielded a 5-year survivorship of 80%, MB still accounts for the leading cause of childhood cancer mortality. In this work, we describe the epigenetic regulator BMI1 as a novel therapeutic target for the treatment of recurrent human Group 3 MB, a childhood brain tumor for which there is virtually no treatment option beyond palliation. Current clinical trials for recurrent MB patients based on genomic profiles of primary, treatment-naive tumors will provide limited clinical benefit since recurrent metastatic MBs are highly genetically divergent from their primary tumor. Using a small molecule inhibitor against BMI1, PTC-028, we were able to demonstrate complete ablation of self-renewal of MB stem cells in vitro. When administered to mice xenografted with patient tumors, we observed significant reduction in tumor burden in both local and metastatic compartments and subsequent increased survival, without neurotoxicity. Strikingly, serial in vivo re-transplantation assays demonstrated a marked reduction in tumor initiation ability of recurrent MB cells upon re-transplantation of PTC-028-treated cells into secondary recipient mouse brains. As Group 3 MB is often metastatic and uniformly fatal at recurrence, with no current or planned trials of targeted therapy, an efficacious targeted agent would be rapidly transitioned to clinical trials.


Subject(s)
Cerebellar Neoplasms/drug therapy , Medulloblastoma/drug therapy , Neoplastic Stem Cells/drug effects , Polycomb Repressive Complex 1/antagonists & inhibitors , Small Molecule Libraries/administration & dosage , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cerebellar Neoplasms/genetics , Cerebellar Neoplasms/metabolism , Child , Epigenesis, Genetic , Gene Expression Regulation, Neoplastic/drug effects , Humans , Medulloblastoma/genetics , Medulloblastoma/metabolism , Mice , Neoplastic Stem Cells/cytology , Neoplastic Stem Cells/metabolism , Polycomb Repressive Complex 1/genetics , Small Molecule Libraries/pharmacology , Treatment Outcome , Up-Regulation/drug effects , Xenograft Model Antitumor Assays
7.
PLoS One ; 13(7): e0199570, 2018.
Article in English | MEDLINE | ID: mdl-30020957

ABSTRACT

Axons normally degenerate during development of the mammalian nervous system, but dysregulation of the same genetically-encoded destructive cellular machinery can destroy crucial structures during adult neurodegenerative diseases. Nerve growth factor (NGF) withdrawal from dorsal root ganglia (DRG) axons is a well-established in vitro experimental model for biochemical and cell biological studies of developmental degeneration. Definitive methods for measuring axon degeneration have been lacking and here we report a novel method of axon degeneration quantification from bulk cultures of DRG that enables objective and automated measurement of axonal density over the entire field of radial axon outgrowth from the ganglion. As proof of principal, this new method, written as an R script called Axoquant 2.0, was used to examine the role of extracellular Ca2+ in the execution of cytoskeletal disassembly during degeneration of NGF-deprived DRG axons. This method can be easily applied to examine degenerative or neuroprotective effects of gene manipulations and pharmacological interventions.


Subject(s)
Axons/metabolism , Neurons/metabolism , Axons/pathology , Biomarkers , Calcium/metabolism , Calcium Chelating Agents/pharmacology , Cells, Cultured , Egtazic Acid/pharmacology , Fluorescent Antibody Technique , Ganglia, Spinal/metabolism , Immunohistochemistry , Molecular Imaging/methods , Nerve Growth Factor/metabolism , Neurons/pathology , Tubulin/metabolism
8.
Oncotarget ; 8(19): 32101-32116, 2017 May 09.
Article in English | MEDLINE | ID: mdl-28404880

ABSTRACT

Breast tumors comprise an infrequent tumor cell population, termed breast tumor initiating cells (BTIC), which sustain tumor growth, seed metastases and resist cytotoxic therapies. Hence therapies are needed to target BTIC to provide more durable breast cancer remissions than are currently achieved. We previously reported that serotonergic system antagonists abrogated the activity of mouse BTIC resident in the mammary tumors of a HER2-overexpressing model of breast cancer. Here we report that antagonists of serotonin (5-hydroxytryptamine; 5-HT) biosynthesis and activity, including US Federal Food and Drug Administration (FDA)-approved antidepressants, targeted BTIC resident in numerous breast tumor cell lines regardless of their clinical or molecular subtype. Notably, inhibitors of tryptophan hydroxylase 1 (TPH1), required for 5-HT biosynthesis in select non-neuronal cells, the serotonin reuptake transporter (SERT) and several 5-HT receptors compromised BTIC activity as assessed by functional sphere-forming assays. Consistent with these findings, human breast tumor cells express TPH1, 5-HT and SERT independent of their molecular or clinical subtype. Exposure of breast tumor cells ex vivo to sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI), reduced BTIC frequency as determined by transplanting drug-treated tumor cells into immune-compromised mice. Moreover, another SSRI (vilazodone; Viibryd) synergized with chemotherapy to shrink breast tumor xenografts in immune-compromised mice by inhibiting tumor cell proliferation and inducing their apoptosis. Collectively our data suggest that antidepressants in combination with cytotoxic anticancer therapies may be an appropriate treatment regimen for testing in clinical trials.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Serotonin Antagonists/pharmacology , Serotonin/metabolism , Animals , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cell Line, Tumor , DNA Copy Number Variations , Disease Models, Animal , Drug Synergism , Female , Gene Expression , Humans , Mice , Serotonin Plasma Membrane Transport Proteins/genetics , Serotonin Plasma Membrane Transport Proteins/metabolism , Signal Transduction/drug effects , Tryptophan Hydroxylase/genetics , Tryptophan Hydroxylase/metabolism , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
9.
PLoS One ; 12(1): e0168669, 2017.
Article in English | MEDLINE | ID: mdl-28045912

ABSTRACT

Claudin-low breast cancer is a molecular type of breast cancer originally identified by gene expression profiling and reportedly associated with poor survival. Claudin-low tumors have been recognised to preferentially display a triple-negative phenotype, however only a minority of triple-negative breast cancers are claudin-low. We sought to identify an immunohistochemical profile for claudin-low tumors that could facilitate their identification in formalin fixed paraffin embedded tumor material. First, an in silico collection of ~1600 human breast cancer expression profiles was assembled and all claudin-low tumors identified. Second, genes differentially expressed between claudin-low tumors and all other molecular subtypes of breast cancer were identified. Third, a number of these top differentially expressed genes were tested using immunohistochemistry for expression in a diverse panel of breast cancer cell lines to determine their specificity for claudin-low tumors. Finally, the immunohistochemical panel found to be most characteristic of claudin-low tumors was examined in a cohort of 942 formalin fixed paraffin embedded human breast cancers with >10 years clinical follow-up to evaluate the clinico-pathologic and survival characteristics of this tumor subtype. Using this approach we determined that claudin-low breast cancer is typically negative for ER, PR, HER2, claudin 3, claudin 4, claudin 7 and E-cadherin. Claudin-low tumors identified with this immunohistochemical panel, were associated with young age of onset, higher tumor grade, larger tumor size, extensive lymphocytic infiltrate and a circumscribed tumor margin. Patients with claudin-low tumors had a worse overall survival when compared to patients with luminal A type breast cancer. Interestingly, claudin-low tumors were associated with a low local recurrence rate following breast conserving therapy. In conclusion, a limited panel of antibodies can facilitate the identification of claudin-low tumors. Furthermore, claudin-low tumors identified in this manner display similar clinical, pathologic and survival characteristics to claudin-low tumors identified from fresh frozen tumor material using gene expression profiling.


Subject(s)
Breast Neoplasms/metabolism , Claudin-1/metabolism , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Breast Neoplasms/genetics , Cell Line, Tumor , Claudin-1/genetics , Cluster Analysis , Cohort Studies , Female , Gene Expression Regulation , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Neoplasm Invasiveness , Neoplasm Recurrence, Local , Phenobarbital/metabolism , Phenotype , Prognosis , Treatment Outcome
10.
Cancer Res ; 77(3): 696-706, 2017 02 01.
Article in English | MEDLINE | ID: mdl-27899382

ABSTRACT

Metastatic relapse is the major cause of death in pediatric neuroblastoma, where there remains a lack of therapies to target this stage of disease. To understand the molecular mechanisms mediating neuroblastoma metastasis, we developed a mouse model using intracardiac injection and in vivo selection to isolate malignant cell subpopulations with a higher propensity for metastasis to bone and the central nervous system. Gene expression profiling revealed primary and metastatic cells as two distinct cell populations defined by differential expression of 412 genes and of multiple pathways, including CADM1, SPHK1, and YAP/TAZ, whose expression independently predicted survival. In the metastatic subpopulations, a gene signature was defined (MET-75) that predicted survival of neuroblastoma patients with metastatic disease. Mechanistic investigations demonstrated causal roles for CADM1, SPHK1, and YAP/TAZ in mediating metastatic phenotypes in vitro and in vivo Notably, pharmacologic targeting of SPHK1 or YAP/TAZ was sufficient to inhibit neuroblastoma metastasis in vivo Overall, we identify gene expression signatures and candidate therapeutics that could improve the treatment of metastatic neuroblastoma. Cancer Res; 77(3); 696-706. ©2017 AACR.


Subject(s)
Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Neuroblastoma/genetics , Neuroblastoma/pathology , Transcriptome , Animals , Cell Line, Tumor , Disease Models, Animal , Gene Expression Profiling , Heterografts , Immunoblotting , Magnetic Resonance Imaging , Male , Mice , Mice, Inbred NOD , Mice, SCID , Oligonucleotide Array Sequence Analysis , X-Ray Microtomography
11.
Acta Neuropathol Commun ; 4(1): 125, 2016 11 28.
Article in English | MEDLINE | ID: mdl-27894339

ABSTRACT

Classified as benign central nervous system (CNS) tumors, pituitary adenomas account for 10% of diagnosed intracranial neoplasms. Although surgery is often curative, patients with invasive macroadenomas continue to experience significant morbidity and are prone to tumor recurrence. Given the identification of human brain tumor-initiating cells (TICs) that initiate and maintain tumor growth while promoting disease progression and relapse in multiple CNS tumors, we investigated whether TICs also drive the growth of human pituitary adenomas. Using a nanoString-based 80-gene custom codeset specific for developmental pathways, we identified a differential stem cell gene expression profile within human pituitary adenomas. Prospective functional characterization of stem cell properties in patient-derived adenomas representing all hormonal subtypes yielded a subtype-dependent self-renewal profile, which was enriched within the CD15+ cell fraction. The tumor-initiating capacity of CD15high adenoma cells was assayed in comparison to CD15low adenomas using in vivo limiting dilutions, which maintained the rare frequency of TICs. Repeated analyses using sorted cell populations for CD15+ TICs compared to CD15- adenoma cells provided further evidence of xenograft tumor formation to support CD15+ cells as putative pituitary adenoma-initiating cells (PAICs). The clinical utility of our findings was established through in silico analyses and comparative gene expression profiling of primary and recurrent pituitary adenomas. CD15 was enriched in recurrent adenomas, which was validated using routine clinical immunohistochemistry in a limited number of samples. Our work reports the first prospective identification of human PAICs using CD15. Patients with CD15high adenomas may therefore benefit from more aggressive surgical interventions and chemo/radiotherapy.


Subject(s)
Adenoma/metabolism , Brain/metabolism , Lewis X Antigen/metabolism , Neoplastic Stem Cells/metabolism , Pituitary Neoplasms/metabolism , Adenoma/genetics , Adult , Aged , Aged, 80 and over , Animals , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Female , Flow Cytometry , Gene Expression Profiling , Humans , Immunohistochemistry , Male , Mice, Inbred NOD , Mice, SCID , Middle Aged , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/metabolism , Neoplasm Transplantation , Pituitary Neoplasms/genetics , Real-Time Polymerase Chain Reaction , Single-Cell Analysis
12.
Mol Oncol ; 10(9): 1461-1472, 2016 11.
Article in English | MEDLINE | ID: mdl-27599694

ABSTRACT

BACKGROUND: In the pediatric cancer neuroblastoma (NB), patients are stratified into low, intermediate or high-risk subsets based in part on MYCN amplification status. While MYCN amplification in general predicts unfavorable outcome, no clinical or genomic factors have been identified that predict outcome within these cohorts of high-risk patients. In particular, it is currently not possible at diagnosis to determine which high-risk neuroblastoma patients will ultimately fail upfront therapy. EXPERIMENTAL DESIGN: We analyzed the prognostic potential of most published gene expression signatures for NB and developed a new prognostic signature to predict outcome for patients with MYCN amplification. Network and pathway analyses identified candidate therapeutic targets for this MYCN-amplified patient subset with poor outcome. RESULTS: Most signatures have a high capacity to predict outcome of unselected NB patients. However, the majority of published signatures, as well as most randomly generated signatures, are highly confounded by MYCN amplification, and fail to predict outcome in subpopulations of high-risk patients with MYCN-amplified NB. We identify a MYCN module signature that predicts patient outcome for those with MYCN-amplified tumors, that also predicts potential tractable therapeutic signaling pathways and targets including the DNA repair enzyme Poly [ADP-ribose] polymerase 1 (PARP1). CONCLUSION: Many prognostic signatures for NB are confounded by MYCN amplification and fail to predict outcome for the subset of high-risk patients with MYCN amplification. We report a MYCN module signature that is associated with distinct patient outcomes, and predicts candidate therapeutic targets in DNA repair pathways, including PARP1 in MYCN-amplified NB.


Subject(s)
Gene Amplification , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Molecular Targeted Therapy , N-Myc Proto-Oncogene Protein/genetics , Neuroblastoma/drug therapy , Neuroblastoma/genetics , Signal Transduction/genetics , Cell Line, Tumor , Cohort Studies , Gene Amplification/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Humans , N-Myc Proto-Oncogene Protein/metabolism , Neuroblastoma/pathology , Phenotype , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , Probability , Prognosis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reproducibility of Results , Treatment Outcome
13.
Oncotarget ; 7(33): 53137-53152, 2016 Aug 16.
Article in English | MEDLINE | ID: mdl-27447971

ABSTRACT

Accumulating data suggests that the initiation and progression of human breast tumors is fueled by a rare subpopulation of tumor cells, termed breast tumor-initiating cells (BTIC), which resist radiotherapy and chemotherapy. Consequently, therapies that abrogate BTIC activity are needed to achieve durable cures for breast cancer patients. To identify such therapies we used a sensitive assay to complete a high-throughput screen of small molecules, including approved drugs, with BTIC-rich mouse mammary tumor cell populations. We found that inhibitors of the serotonin reuptake transporter (SERT) and serotonin receptors, which include approved drugs used to treat mood disorders, were potent inhibitors of mouse BTIC activity as determined by functional sphere-forming assays and the initiation of tumor formation by transplant of drug-exposed tumor cells into syngeneic mice. Moreover, sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI), synergized with docetaxel (Taxotere) to shrink mouse breast tumors in vivo. Hence drugs targeting the serotonergic system might be repurposed to treat breast cancer patients to afford more durable breast cancer remissions.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Breast Neoplasms/drug therapy , Mammary Neoplasms, Experimental/drug therapy , Neoplastic Stem Cells/drug effects , Sertraline/pharmacology , Animals , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Docetaxel , Drug Synergism , Female , Humans , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Mice, Transgenic , Neoplastic Stem Cells/metabolism , Serotonin/metabolism , Serotonin Plasma Membrane Transport Proteins/metabolism , Selective Serotonin Reuptake Inhibitors/administration & dosage , Selective Serotonin Reuptake Inhibitors/pharmacology , Sertraline/administration & dosage , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Taxoids/administration & dosage , Taxoids/pharmacology
14.
BMC Cancer ; 16: 555, 2016 07 28.
Article in English | MEDLINE | ID: mdl-27469239

ABSTRACT

BACKGROUND: Lymph node (LN) status is the most important prognostic variable used to guide ER positive (+) breast cancer treatment. While a positive nodal status is traditionally associated with a poor prognosis, a subset of these patients respond well to treatment and achieve long-term survival. Several gene signatures have been established as a means of predicting outcome of breast cancer patients, but the development and indication for use of these assays varies. Here we compare the capacity of two approved gene signatures and a third novel signature to predict outcome in distinct LN negative (-) and LN+ populations. We also examine biological differences between tumours associated with LN- and LN+ disease. METHODS: Gene expression data from publically available data sets was used to compare the ability of Oncotype DX and Prosigna to predict Distant Metastasis Free Survival (DMFS) using an in silico platform. A novel gene signature (Ellen) was developed by including patients with both LN- and LN+ disease and using Prediction Analysis of Microarrays (PAM) software. Gene Set Enrichment Analysis (GSEA) was used to determine biological pathways associated with patient outcome in both LN- and LN+ tumors. RESULTS: The Oncotype DX gene signature, which only used LN- patients during development, significantly predicted outcome in LN- patients, but not LN+ patients. The Prosigna gene signature, which included both LN- and LN+ patients during development, predicted outcome in both LN- and LN+ patient groups. Ellen was also able to predict outcome in both LN- and LN+ patient groups. GSEA suggested that epigenetic modification may be related to poor outcome in LN- disease, whereas immune response may be related to good outcome in LN+ disease. CONCLUSIONS: We demonstrate the importance of incorporating lymph node status during the development of prognostic gene signatures. Ellen may be a useful tool to predict outcome of patients regardless of lymph node status, or for those with unknown lymph node status. Finally we present candidate biological processes, unique to LN- and LN+ disease, that may indicate risk of relapse.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Lymphatic Metastasis/genetics , Transcriptome , Adult , Aged , Aged, 80 and over , Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Female , Gene Expression Profiling , Humans , Kaplan-Meier Estimate , Lymphatic Metastasis/pathology , Middle Aged , Oligonucleotide Array Sequence Analysis , Proportional Hazards Models , Receptor, ErbB-2/biosynthesis , Receptors, Estrogen/biosynthesis , Tamoxifen/therapeutic use
15.
J Neurooncol ; 126(1): 57-67, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26498281

ABSTRACT

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults with average disease relapse at 9 months and median survival rarely extending beyond 15 months. Brain tumor stem cells (BTSCs) have been implicated in not only initiating GBM but also conferring resistance to therapy. However, it is not clear whether the BTSC population that initiates tumor growth is also responsible for GBM recurrence. In this study, we have developed a novel in vitro treatment model to profile the evolution of primary treatment-naïve GBM BTSCs through chemoradiotherapy. We report that our in vitro model enriched for a CD15+/CD133- BTSC population, mirroring the phenotype of BTSCs in recurrent GBM. We also show that in vitro treatment increased stem cell gene expression as well as self-renewal capacity of primary GBMs. In addition, the chemoradiotherapy-refractory gene signature obtained from gene expression profiling identified a hyper-aggressive subtype of glioma. The delivery of in vitro chemoradiotherapy to primary GBM BTSCs models several aspects of recurrent GBM biology, and could be used as a discovery and drug-screening platform to uncover new biological drivers and therapeutic targets in GBM.


Subject(s)
Brain Neoplasms/pathology , Gene Expression Regulation, Neoplastic/physiology , Glioblastoma/pathology , Neoplastic Stem Cells/pathology , Aged , Aged, 80 and over , Analysis of Variance , Antigens, CD/metabolism , Antinematodal Agents/pharmacology , Antineoplastic Agents/pharmacology , Cell Self Renewal/physiology , Dose-Response Relationship, Drug , Female , Flow Cytometry , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/radiation effects , Humans , Male , Middle Aged , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/radiation effects , Polycomb Repressive Complex 1/genetics , Polycomb Repressive Complex 1/metabolism , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Tumor Cells, Cultured
16.
Biochim Biophys Acta ; 1849(12): 1432-41, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26514431

ABSTRACT

Low oxygen tension (hypoxia) is a common characteristic of solid tumors and strongly correlates with poor prognosis and resistance to treatment. In response to hypoxia, cells initiate a cascade of transcriptional events regulated by the hypoxia inducible factor-1 (HIF-1) heterodimer. Since the oxygen-sensitive HIF-1α subunit is stabilized during hypoxia, it functions as the regulatory subunit of the protein. To date, while the mechanisms governing HIF-1α protein stabilization and function have been well studied, those governing HIF1A gene expression are not fully understood. However, recent studies have suggested that methylation of a HIF-1 binding site in the HIF1A promoter prevents its autoregulation. Here we report that the POZ-ZF transcription factor Kaiso modulates HIF1A gene expression by binding to the methylated HIF1A promoter in a region proximal to the autoregulatory HIF-1 binding site. Interestingly, Kaiso's regulation of HIF1A occurs primarily during hypoxia, which is consistent with the finding that Kaiso protein levels peak after 4 h of hypoxic incubation and return to normoxic levels after 24 h. Our data thus support a role for Kaiso in fine-tuning HIF1A gene expression after extended periods of hypoxia.


Subject(s)
DNA Methylation , Gene Expression Regulation, Neoplastic , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , Neoplasm Proteins/physiology , Transcription Factors/physiology , Breast Neoplasms/genetics , Cell Hypoxia/genetics , Colonic Neoplasms/genetics , Datasets as Topic/statistics & numerical data , Female , Gene Regulatory Networks , HCT116 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Promoter Regions, Genetic/genetics , Signal Transduction , Transcription, Genetic
17.
Oncotarget ; 6(29): 27461-77, 2015 Sep 29.
Article in English | MEDLINE | ID: mdl-26314961

ABSTRACT

Brain metastases (BM) represent the most common tumor to affect the adult central nervous system. Despite the increasing incidence of BM, likely due to consistently improving treatment of primary cancers, BM remain severely understudied. In this study, we utilized patient-derived stem cell lines from lung-to-brain metastases to examine the regulatory role of STAT3 in brain metastasis initiating cells (BMICs). Annotation of our previously described BMIC regulatory genes with protein-protein interaction network mapping identified STAT3 as a novel protein interactor. STAT3 knockdown showed a reduction in BMIC self-renewal and migration, and decreased tumor size in vivo. Screening of BMIC lines with a library of STAT3 inhibitors identified one inhibitor to significantly reduce tumor formation. Meta-analysis identified the oncomir microRNA-21 (miR-21) as a target of STAT3 activity. Inhibition of miR-21 displayed similar reductions in BMIC self-renewal and migration as STAT3 knockdown. Knockdown of STAT3 also reduced expression of known downstream targets of miR-21. Our studies have thus identified STAT3 and miR-21 as cooperative regulators of stemness, migration and tumor initiation in lung-derived BM. Therefore, STAT3 represents a potential therapeutic target in the treatment of lung-to-brain metastases.


Subject(s)
Brain Neoplasms/secondary , Gene Expression Regulation, Neoplastic , Lung Neoplasms/pathology , MicroRNAs/metabolism , STAT3 Transcription Factor/metabolism , Animals , Cell Line, Tumor , Cell Movement , Genes, Regulator , Humans , Inhibitory Concentration 50 , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Metastasis , Neoplasm Transplantation , Protein Interaction Mapping , Proteomics , RNA, Small Interfering/metabolism , Stem Cells/cytology
18.
Clin Cancer Res ; 21(23): 5324-37, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26152745

ABSTRACT

PURPOSE: Clonal evolution of cancer may be regulated by determinants of stemness, specifically self-renewal, and current therapies have not considered how genetic perturbations or properties of stemness affect such functional processes. Glioblastoma-initiating cells (GICs), identified by expression of the cell surface marker CD133, are shown to be chemoradioresistant. In the current study, we sought to elucidate the functional role of CD133 in self-renewal and identify compounds that can specifically target this CD133(+) treatment-refractory population. EXPERIMENTAL DESIGN: Using gain/loss-of-function studies for CD133 we assessed the in vitro self-renewal and in vivo tumor formation capabilities of patient-derived glioblastoma cells. We generated a CD133 signature combined with an in silico screen to find compounds that target GICs. Self-renewal and proliferation assays on CD133-sorted samples were performed to identify the preferential action of hit compounds. In vivo efficacy of the lead compound pyrvinium was assessed in intracranial GIC xenografts and survival studies. Lastly, microarray analysis was performed on pyrvinium-treated GICs to discover core signaling events involved. RESULTS: We discovered pyrvinium, a small-molecule inhibitor of GIC self-renewal in vitro and in vivo, in part through inhibition of Wnt/ß-catenin signaling and other essential stem cell regulatory pathways. We provide a therapeutically tractable strategy to target self-renewing, chemoradioresistant, and functionally important CD133(+) stem cells that drive glioblastoma relapse and mortality. CONCLUSIONS: Our study provides an integrated approach for the eradication of clonal populations responsible for cancer progression, and may apply to other aggressive and heterogeneous cancers.


Subject(s)
Antineoplastic Agents/pharmacology , Brain Neoplasms/metabolism , Glioblastoma/metabolism , Glycoproteins/antagonists & inhibitors , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Peptides/antagonists & inhibitors , Pyrvinium Compounds/pharmacology , AC133 Antigen , Animals , Antigens, CD/genetics , Antigens, CD/metabolism , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/mortality , Cell Proliferation , Cell Self Renewal/drug effects , Cell Self Renewal/genetics , Disease Models, Animal , Gene Expression , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , Gene Regulatory Networks , Glioblastoma/drug therapy , Glioblastoma/genetics , Glioblastoma/mortality , Glycoproteins/genetics , Glycoproteins/metabolism , Humans , Peptides/genetics , Peptides/metabolism , Prognosis , Signal Transduction/drug effects , Spheroids, Cellular , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
19.
Oncotarget ; 6(19): 17713-24, 2015 Jul 10.
Article in English | MEDLINE | ID: mdl-25991675

ABSTRACT

PURPOSE: Basal-like breast cancer (BLBC) is a molecular subtype of breast cancer associated with poor clinical outcome, although some patients with BLBC experience long-term survival. Apart from nodal status, current clinical/histopathological variables show little capacity to identify BLBC patients at either high- or low-risk of disease recurrence. Accordingly, we sought to develop a network based genomic predictor for predicting the outcome of patients with BLBC. EXPERIMENTAL DESIGN: We performed network analysis on global gene expression profiling data of BLBCs, and identified BLBC network modules associated with AP-1 transcription, G-protein coupled receptors, and T-, B-, and NK-cells that are significant predictors of BLBC patient survival. RESULTS: In gene expression and tissue microarray (TMA) validation cohorts of 210 and 102 BLBC patients, respectively, the identified network modules were robustly associated with patient outcome. In the gene expression validation cohort, the Kaplan-Meier estimate for 10-year survival in the low-risk group was 90%, whereas in the high-risk group it was a 56%. In the TMA cohort, the Kaplan-Meier estimate for 10-year survival in the low-risk group was 98%, whereas in the high-risk group it was 71%. CONCLUSIONS: The capacity to distinguish between patients with BLBC at high- or low-risk of recurrence at the time of diagnosis could permit timely intervention with more aggressive therapeutic regimens in those patients predicted to be high-risk, and to avoid such therapy in low-risk patients.


Subject(s)
Breast Neoplasms/classification , Breast Neoplasms/genetics , Breast Neoplasms/mortality , Gene Expression Profiling/methods , Female , Humans , Kaplan-Meier Estimate , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Oligonucleotide Array Sequence Analysis , Prognosis , Proportional Hazards Models , Tissue Array Analysis
20.
Oncotarget ; 6(9): 7040-52, 2015 Mar 30.
Article in English | MEDLINE | ID: mdl-25749523

ABSTRACT

Chemotherapy fails to provide durable cure for the majority of cancer patients. To identify mechanisms associated with chemotherapy resistance, we identified genes differentially expressed before and after chemotherapeutic treatment of breast cancer patients. Treatment response resulted in either increased or decreased cell cycle gene expression. Tumors in which cell cycle gene expression was increased by chemotherapy were likely to be chemotherapy sensitive, whereas tumors in which cell cycle gene transcripts were decreased by chemotherapy were resistant to these agents. A gene expression signature that predicted these changes proved to be a robust and novel index that predicted the response of patients with breast, ovarian, and colon tumors to chemotherapy. Investigations in tumor cell lines supported these findings, and linked treatment induced cell cycle changes with p53 signaling and G1/G0 arrest. Hence, chemotherapy resistance, which can be predicted based on dynamics in cell cycle gene expression, is associated with TP53 integrity.


Subject(s)
Breast Neoplasms/drug therapy , Cell Cycle/drug effects , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic/drug effects , Neoplasms/drug therapy , Neoplasms/pathology , Antineoplastic Agents/chemistry , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Line, Tumor , Female , Flow Cytometry , Gene Expression Profiling , Genes, Reporter , Humans , Immunohistochemistry , MCF-7 Cells , Signal Transduction , Tumor Suppressor Protein p53/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...