ABSTRACT
Glioblastoma (GBM) is the most malignant and aggressive form of glioma and is associated with a poor survival rate. Latest generation Tumour Necrosis Factor Related Apoptosis-Inducing Ligand (TRAIL)-based therapeutics potently induce apoptosis in cancer cells, including GBM cells, by binding to death receptors. However, the blood-brain barrier (BBB) is a major obstacle for these biologics to enter the central nervous system (CNS). We therefore investigated if antibody-based fusion proteins that combine hexavalent TRAIL and angiopep-2 (ANG2) moieties can be developed, with ANG2 promoting receptor-mediated transcytosis (RMT) across the BBB. We demonstrate that these fusion proteins retain the potent apoptosis induction of hexavalent TRAIL-receptor agonists. Importantly, blood-brain barrier cells instead remained highly resistant to this fusion protein. Binding studies indicated that ANG2 is active in these constructs but that TRAIL-ANG2 fusion proteins bind preferentially to BBB endothelial cells via the TRAIL moiety. Consequently, transport studies indicated that TRAIL-ANG2 fusion proteins can, in principle, be shuttled across BBB endothelial cells, but that low TRAIL receptor expression on BBB endothelial cells interferes with efficient transport. Our work therefore demonstrates that TRAIL-ANG2 fusion proteins remain highly potent in inducing apoptosis, but that therapeutic avenues will require combinatorial strategies, such as TRAIL-R masking, to achieve effective CNS transport.
Subject(s)
Blood-Brain Barrier/metabolism , Brain Neoplasms , Endothelium/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Glioblastoma , Neoplasm Proteins , Peptides/pharmacology , TNF-Related Apoptosis-Inducing Ligand , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Glioblastoma/drug therapy , Glioblastoma/metabolism , HCT116 Cells , HEK293 Cells , Humans , Neoplasm Proteins/agonists , Neoplasm Proteins/biosynthesis , TNF-Related Apoptosis-Inducing Ligand/agonists , TNF-Related Apoptosis-Inducing Ligand/biosynthesisABSTRACT
The knowledge of the structure, function, and abundance of specific proteins related to the EMT process is essential for developing effective diagnostic approaches to cancer with the perspective of diagnosis and therapy of malignancies. The success of all-trans retinoic acid (ATRA) differentiation therapy in acute promyelocytic leukemia has stimulated studies in the treatment of other tumors with ATRA. This review will discuss the impact of ATRA use, emphasizing epithelial-mesenchymal transition (EMT) proteins in breast cancer, of which metastasis and recurrence are major causes of death.
Subject(s)
Breast Neoplasms/metabolism , Epithelial-Mesenchymal Transition , Neoplasm Proteins/metabolism , Receptors, Retinoic Acid/metabolism , Tretinoin/metabolism , Animals , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Female , Humans , Neoplasm Metastasis , Neoplasm Proteins/agonists , Receptors, Retinoic Acid/agonistsABSTRACT
Progesterone and its synthetic analogues act on cells through different types of receptors, affecting proliferation and apoptosis. These compounds exert their effect through the nuclear receptors and the insufficiently studied membrane progesterone receptors (mPRs) belonging to the progestin and adiponectin Q receptor (PAQR) family. We have identified two selective ligands of mPRs that activate only this type of progesterone receptors - 19-hydroxypregn-4-en-20-one (LS-01) and 19-hydroxy-5ß-pregn-3-en-20-one (LS-02). The goal of this work is to study the effect of these compounds on proliferation and death of human pancreatic adenocarcinoma cells BxPC3 and involvement of the two kinases (p38 MAPK and JNK) in signaling pathways activated by progestins through mPRs. It was shown that progesterone and the compound LS-01 significantly (p < 0.05) inhibited the BxPC3 cell viability, with JNK serving as a mediator. The identified targets of these two steroids are the genes of the proteins Ki67, cyclin D1, PCNA, and p21. Progesterone and the compound LS-01 significantly (p < 0.05) stimulate DNA fragmentation, enhancing the cell death. The p38 mitogen-activated protein kinase (MAPK) is a key mediator of this process. The BCL2A1 protein gene was identified as a target of both steroids. The compound LS-02 significantly (p < 0.05) alters membrane permeability and changes the exposure of phosphatidylserine on the outer membrane leaflet, also enhancing the cell death. This compound acts on these processes by activating both kinases, JNK and p38 MAPK. The compound LS-02 targets the genes encoding the proteins HRK, caspase 9, and DAPK.
Subject(s)
Apoptosis/drug effects , Cytotoxins/pharmacology , MAP Kinase Signaling System/drug effects , Neoplasm Proteins/metabolism , Pancreatic Neoplasms/metabolism , Receptors, Progesterone/metabolism , Cell Line, Tumor , Humans , Ligands , Neoplasm Proteins/agonists , Neoplasm Proteins/genetics , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Receptors, Progesterone/agonists , Receptors, Progesterone/genetics , Pancreatic NeoplasmsABSTRACT
The mammalian target of rapamycin (mTOR) is a sensor of nutrient status and plays an important role in cell growth and metabolism. Although inhibition of mTOR signaling promotes tumor cell death and several mTOR inhibitors have been used clinically, recent reports have shown that co-treatment with MHY1485, an mTOR activator, enhances the anti-cancer effects of anti-PD-1 antibody and 5-fluorouracil. However, it remains unclear whether MHY1485 treatment alters the effects of radiation on tumor cells. In this study, the radiosensitizing effects of MHY1485 were investigated using murine CT26 and LLC cell lines. We examined mTOR signaling, tumor cell growth, colony formation, apoptosis, senescence, oxidative stress, p21 accumulation and endoplasmic reticulum (ER) stress levels in cells treated with MHY1485 and radiation, either alone or together. We found that MHY1485 treatment inhibited growth and colony formation in both cell lines under irradiation and no-irradiation conditions, results that were not fully consistent with MHY1485's known role in activating mTOR signaling. Furthermore, we found that combined treatment with MHY1485 and radiation significantly increased apoptosis and senescence in tumor cells in association with oxidative stress, ER stress and p21 stabilization, compared to radiation treatment alone. Our results suggested that MHY1485 enhances the radiosensitivity of tumor cells by a mechanism that may differ from MHY1485's role in mTOR activation.
Subject(s)
Apoptosis/drug effects , Cellular Senescence/drug effects , Morpholines/pharmacology , Neoplasm Proteins/agonists , TOR Serine-Threonine Kinases/drug effects , Triazines/pharmacology , Animals , Apoptosis/radiation effects , Carcinoma, Lewis Lung/genetics , Carcinoma, Lewis Lung/pathology , Cell Cycle/drug effects , Cell Cycle/radiation effects , Cell Line, Tumor , Cellular Senescence/radiation effects , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Drug Screening Assays, Antitumor , Endoplasmic Reticulum Stress/drug effects , Endoplasmic Reticulum Stress/radiation effects , Genes, p53 , Genes, ras , Lipid Peroxidation/drug effects , Lipid Peroxidation/radiation effects , Mice , Mitochondria/drug effects , Mitochondria/radiation effects , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Signal Transduction/drug effects , Signal Transduction/radiation effects , Tumor Stem Cell AssayABSTRACT
The high mortality rate together with an ever-growing number of annual cases have defined neoplastic disorders as "the real 21st-century disease". Its dubious distinction also results from conventional therapy failure, which has made cancer an orphan disease. Therefore, innovative and alternative therapeutic strategies are mandatory. The ability to leverage human naturally occurring anti-tumor defenses has always represented a fascinating perspective, and the immuno blockage approval in cancer treatment represents in timeline the latest success. As a multifunctional organ, adipose tissue releases a large amount of adipokines having both carcinogenic and antitumor properties. The negative correlation between serum levels and risk for developing malignancies, as well as the huge number of existing preclinical studies, have identified adiponectin as a potential anticancer adipokine. Nevertheless, its usage in clinical has constantly clashed with the inability to reproduce a mimic synthetic compound. Between 2011 and 2013, two distinct adiponectin receptor agonists were recognized, opening new scenarios even in cancer. Here, we review the first orally active adiponectin receptor agonists AdipoRon, from the discovery to the anticancer evidence. Including our latest findings in osteosarcoma models, we summarize AdipoRon and other existing agonists state-of-art, questioning about the feasibility assessment of this strategy in cancer treatment.
Subject(s)
Bone Neoplasms/drug therapy , Neoplasm Proteins/agonists , Osteosarcoma/drug therapy , Piperidines/therapeutic use , Receptors, Adiponectin/agonists , Animals , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Humans , Neoplasm Proteins/metabolism , Osteosarcoma/metabolism , Osteosarcoma/pathology , Receptors, Adiponectin/metabolismABSTRACT
Rationale: Clinical interest in combining targeted radionuclide therapies (TRT) with immunotherapies is growing. External beam radiation therapy (EBRT) activates a type 1 interferon (IFN1) response mediated via stimulator of interferon genes (STING), and this is critical to its therapeutic interaction with immune checkpoint blockade. However, little is known about the time course of IFN1 activation after EBRT or whether this may be induced by decay of a TRT source. Methods: We examined the IFN1 response and expression of immune susceptibility markers in B78 and B16 melanomas and MOC2 head and neck cancer murine models using qPCR and western blot. For TRT, we used 90Y chelated to NM600, an alkylphosphocholine analog that exhibits selective uptake and retention in tumor cells including B78 and MOC2. Results: We observed significant IFN1 activation in all cell lines, with peak activation in B78, B16, and MOC2 cell lines occurring 7, 7, and 1 days, respectively, following RT for all doses. This effect was STING-dependent. Select IFN response genes remained upregulated at 14 days following RT. IFN1 activation following STING agonist treatment in vitro was identical to RT suggesting time course differences between cell lines were mediated by STING pathway kinetics and not DNA damage susceptibility. In vivo delivery of EBRT and TRT to B78 and MOC2 tumors resulted in a comparable time course and magnitude of IFN1 activation. In the MOC2 model, the combination of 90Y-NM600 and dual checkpoint blockade therapy reduced tumor growth and prolonged survival compared to single agent therapy and cumulative dose equivalent combination EBRT and dual checkpoint blockade therapy. Conclusions: We report the time course of the STING-dependent IFN1 response following radiation in multiple murine tumor models. We show the potential of TRT to stimulate IFN1 activation that is comparable to that observed with EBRT and this may be critical to the therapeutic integration of TRT with immunotherapies.
Subject(s)
Carcinoma, Squamous Cell/radiotherapy , Interferon Type I/physiology , Melanoma, Experimental/radiotherapy , Animals , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/physiopathology , Cell Line, Tumor , Combined Modality Therapy , Dose-Response Relationship, Radiation , Female , Gene Expression Regulation, Neoplastic/radiation effects , Gene Knockout Techniques , Head and Neck Neoplasms/pathology , Immune Checkpoint Inhibitors , Interferon Type I/biosynthesis , Interferon Type I/genetics , Lymphocytes/drug effects , Lymphocytes/radiation effects , Melanoma, Experimental/immunology , Melanoma, Experimental/physiopathology , Membrane Proteins/agonists , Membrane Proteins/deficiency , Membrane Proteins/genetics , Membrane Proteins/physiology , Mice , Mice, Inbred C57BL , Neoplasm Proteins/agonists , Neoplasm Proteins/physiology , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/therapeutic use , Time Factors , Tumor Protein, Translationally-Controlled 1 , Tumor Stem Cell Assay , Up-Regulation , Yttrium Radioisotopes/pharmacokinetics , Yttrium Radioisotopes/therapeutic useABSTRACT
Prostate cancer (PC) is driven by androgen receptor (AR) activity, a master regulator of prostate development and homeostasis. Frontline therapies for metastatic PC deprive the AR of the activating ligands testosterone (T) and dihydrotestosterone (DHT) by limiting their biosynthesis or blocking AR binding. Notably, AR signaling is dichotomous, inducing growth at lower activity levels, while suppressing growth at higher levels. Recent clinical studies have exploited this effect by administration of supraphysiological concentrations of T, resulting in clinical responses and improvements in quality of life. However, the use of T as a therapeutic agent in oncology is limited by poor drug-like properties as well as rapid and variable metabolism. Here, we investigated the antitumor effects of selective AR modulators (SARMs), which are small-molecule nonsteroidal AR agonists developed to treat muscle wasting and cachexia. Several orally administered SARMs activated the AR program in PC models. AR cistromes regulated by steroidal androgens and SARMs were superimposable. Coregulatory proteins including HOXB13 and GRHL2 comprised AR complexes assembled by both androgens and SARMs. At bioavailable concentrations, SARMs repressed MYC oncoprotein expression and inhibited the growth of castration-sensitive and castration-resistant PC in vitro and in vivo. These results support further clinical investigation of SARMs for treating advanced PC.
Subject(s)
Androgens/pharmacology , Neoplasm Proteins/agonists , Neoplasm Proteins/metabolism , Prostatic Neoplasms/metabolism , Receptors, Androgen/metabolism , Signal Transduction/drug effects , Animals , Cell Line, Tumor , Dihydrotestosterone/metabolism , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Proteins/genetics , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Receptors, Androgen/genetics , Signal Transduction/geneticsABSTRACT
Myelofibrosis (MF) is a non-BCR-ABL myeloproliferative neoplasm associated with poor outcomes. Current treatment has little effect on the natural history of the disease. MF results from complex interactions between (a) the malignant clone, (b) an inflammatory context, and (c) remodeling of the bone marrow (BM) microenvironment. Each of these points is a potential target of PPARγ activation. Here, we demonstrated the therapeutic potential of PPARγ agonists in resolving MF in 3 mouse models. We showed that PPARγ agonists reduce myeloproliferation, modulate inflammation, and protect the BM stroma in vitro and ex vivo. Activation of PPARγ constitutes a relevant therapeutic target in MF, and our data support the possibility of using PPARγ agonists in clinical practice.
Subject(s)
Antineoplastic Agents/pharmacology , Hematologic Neoplasms/drug therapy , Neoplasm Proteins/agonists , Neoplasms, Experimental/drug therapy , PPAR gamma/agonists , Primary Myelofibrosis/drug therapy , Animals , Bone Marrow Cells/metabolism , Bone Marrow Cells/pathology , Disease Models, Animal , Hematologic Neoplasms/genetics , Hematologic Neoplasms/metabolism , Hematologic Neoplasms/pathology , Mice , Mice, Transgenic , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , PPAR gamma/genetics , PPAR gamma/metabolism , Primary Myelofibrosis/genetics , Primary Myelofibrosis/metabolism , Primary Myelofibrosis/pathology , Tumor Microenvironment/drug effects , Tumor Microenvironment/geneticsABSTRACT
Preparations of Echinacea purpurea (E. purpurea) are widely used for the management of upper respiratory infections, influenza, and common cold, often in combination with other conventional drugs. However, the potential of phytochemical constituents of E. purpurea to cause herb-drug interactions via ABCB1 and ABCG2 efflux transporters remains elusive. The purpose of this study was to investigate the impact of E. purpurea-derived caffeic acid derivatives (cichoric acid and echinacoside) and tetraenes on the mRNA and protein expression levels as well as on transport activity of ABCB1 and ABCG2 in intestinal (Caco-2) and liver (HepG2) cell line models. The safety of these compounds was investigated by estimating EC20 values of cell viability assays in both cell lines. Regulation of ABCB1 and ABCG2 protein in these cell lines were analyzed after 24 h exposure to the compounds at 1, 10, and 50 µg/mL. Bidirectional transport of 0.5 µg/mL Hoechst 33342 and 5 µM rhodamine across Caco-2 monolayer and profiling for intracellular concentrations of the fluorophores in both cell lines were conducted to ascertain inhibition effects of the compounds. Cichoric acid showed no cytotoxic effect, while the EC20 values of tetraenes and echinacoside were 45.0 ± 3.0 and 52.0 ± 4.0 µg/mL in Caco-2 cells and 28.0 ± 4.3 and 62.0 ± 9.9 µg/mL in HepG2 cells, respectively. In general, the compounds showed heterogeneous induction of ABCB1 with the strongest 3.6 ± 1.2-fold increase observed for 10 µg/mL tetraenes in Caco-2 cells (p < 0.001). However, the compounds did not induce ABCG2. None of the phytocompounds inhibited significantly net flux of the fluorophores across Caco-2 monolayers. Overall, tetraenes moderately induced ABCB1 but not ABCG2 in Caco-2 and HepG2 cells while no compound significantly inhibited activity of these transporters at clinically relevant concentration to cause herb-drug interactions.
Subject(s)
Caffeic Acids/pharmacology , Echinacea/chemistry , Glycosides/pharmacology , Herb-Drug Interactions , Succinates/pharmacology , ATP Binding Cassette Transporter, Subfamily B/agonists , ATP Binding Cassette Transporter, Subfamily B/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2/agonists , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , Caco-2 Cells , Hep G2 Cells , Hepatobiliary Elimination , Humans , Intestinal Elimination , Neoplasm Proteins/agonists , Neoplasm Proteins/metabolismABSTRACT
Stromal-interaction molecules (STIM1/2) sense endoplasmic reticulum (ER) Ca2+ depletion and activate Orai channels. However, the choreography of interactions between native STIM/Orai proteins under physiological agonist stimulation is unknown. We show that the five STIM1/2 and Orai1/2/3 proteins are non-redundant and function together to ensure the graded diversity of mammalian Ca2+ signaling. Physiological Ca2+ signaling requires functional interactions between STIM1/2, Orai1/2/3, and IP3Rs, ensuring that receptor-mediated Ca2+ release is tailored to Ca2+ entry and nuclear factor of activated T cells (NFAT) activation. The N-terminal Ca2+-binding ER-luminal domains of unactivated STIM1/2 inhibit IP3R-evoked Ca2+ release. A gradual increase in agonist intensity and STIM1/2 activation relieves IP3R inhibition. Concomitantly, activated STIM1/2 C termini differentially interact with Orai1/2/3 as agonist intensity increases. Thus, coordinated and omnitemporal functions of all five STIM/Orai and IP3Rs translate the strength of agonist stimulation to precise levels of Ca2+ signaling and NFAT induction, ensuring the fidelity of complex mammalian Ca2+ signaling.
Subject(s)
Calcium Channels/metabolism , Calcium Signaling , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Neoplasm Proteins/metabolism , ORAI1 Protein/metabolism , ORAI2 Protein/metabolism , Stromal Interaction Molecule 1/metabolism , Stromal Interaction Molecule 2/metabolism , Calcium Channels/genetics , Calcium Signaling/drug effects , Carbachol/pharmacology , HEK293 Cells , Humans , Inositol 1,4,5-Trisphosphate Receptors/genetics , Membrane Potentials , Models, Biological , Muscarinic Agonists/pharmacology , NFATC Transcription Factors/genetics , NFATC Transcription Factors/metabolism , Neoplasm Proteins/agonists , Neoplasm Proteins/genetics , ORAI1 Protein/genetics , ORAI2 Protein/genetics , Protein Binding , Receptor Cross-Talk , Stromal Interaction Molecule 1/agonists , Stromal Interaction Molecule 1/genetics , Stromal Interaction Molecule 2/agonists , Stromal Interaction Molecule 2/genetics , Time FactorsABSTRACT
Chronic lymphocytic leukemia (CLL) remains incurable despite B-cell receptor-targeted inhibitors revolutionizing treatment. This suggests that other signaling molecules are involved in disease escape mechanisms and resistance. Toll-like receptor 9 (TLR9) is a promising candidate that is activated by unmethylated cytosine guanine dinucleotide-DNA. Here, we show that plasma from patients with CLL contains significantly more unmethylated DNA than plasma from healthy control subjects (P < .0001) and that cell-free DNA levels correlate with the prognostic markers CD38, ß2-microglobulin, and lymphocyte doubling time. Furthermore, elevated cell-free DNA was associated with shorter time to first treatment (hazard ratio, 4.0; P = .003). We also show that TLR9 expression was associated with in vitro CLL cell migration (P < .001), and intracellular endosomal TLR9 strongly correlated with aberrant surface expression (sTLR9; r = 0.9). In addition, lymph node-derived CLL cells exhibited increased sTLR9 (P = .016), and RNA-sequencing of paired sTLR9hi and sTLR9lo CLL cells revealed differential transcription of genes involved in TLR signaling, adhesion, motility, and inflammation in sTLR9hi cells. Mechanistically, a TLR9 agonist, ODN2006, promoted CLL cell migration (P < .001) that was mediated by p65 NF-κB and STAT3 transcription factor activation. Importantly, autologous plasma induced the same effects, which were reversed by a TLR9 antagonist. Furthermore, high TLR9 expression promoted engraftment and rapid disease progression in a NOD/Shi-scid/IL-2Rγnull mouse xenograft model. Finally, we showed that dual targeting of TLR9 and Bruton's tyrosine kinase (BTK) was strongly synergistic (median combination index, 0.2 at half maximal effective dose), which highlights the distinct role for TLR9 signaling in CLL and the potential for combined targeting of TLR9 and BTK as a more effective treatment strategy in this incurable disease.
Subject(s)
Cell Movement/drug effects , Gene Expression Regulation, Leukemic/drug effects , Leukemia, Lymphocytic, Chronic, B-Cell , Neoplasm Proteins , Oligodeoxyribonucleotides/pharmacology , Toll-Like Receptor 9 , Animals , Female , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Male , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Proteins/agonists , Neoplasm Proteins/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 9/agonists , Toll-Like Receptor 9/metabolism , Xenograft Model Antitumor AssaysABSTRACT
Regulatory T cells (Treg cells) restrict immune system activity, such as in response to self-antigens, and are switched on by tumor necrosis factor receptor 2 (TNFR2). Therapeutic activation of TNFR2, thereby expanding Treg cells and suppressing immune activity, may be beneficial to patients with various inflammatory diseases. Here, we characterized a new human TNFR2-directed antibody agonist isolated from mice. We found that the antibody agonist expanded the number of Treg cells within cultures of primary human CD4+ T cells from healthy donors and patients with type 1 diabetes or Sézary syndrome. These Treg cells had increased metabolic gene expression and intracellular itaconate concentrations, characteristics associated with maximally suppressive, anti-inflammatory Treg cells. Furthermore, antibody-expanded Treg cells repressed the activity of primary human CD8+ effector T cells (Teff cells). Epitope mapping suggested that the antibody bound to TNFR2 through a natural cross-linking surface and that Treg cell expansion was independent of the antibody Fc region. In addition, Treg cell expansion was not increased by adding either supplemental TNF ligand or a cross-linking reagent, suggesting that the antibody agonist by itself can elicit maximal activity, a notion that was confirmed by increased secretion of soluble TNFR2. Pending in vivo tests, these features indicate that this TNFR2 antibody agonist has the potential to safely and effectively treat various inflammatory disorders.
Subject(s)
Antibodies, Neoplasm/immunology , Diabetes Mellitus, Type 1/immunology , Neoplasm Proteins , Receptors, Tumor Necrosis Factor, Type II , Sezary Syndrome/immunology , Adult , Animals , Female , Humans , Male , Mice , Middle Aged , Neoplasm Proteins/agonists , Neoplasm Proteins/immunology , Receptors, Tumor Necrosis Factor, Type II/agonists , Receptors, Tumor Necrosis Factor, Type II/immunology , T-Lymphocytes, RegulatoryABSTRACT
Epidermal growth factor receptor (EGFR) activation plays a pivotal role in EGFR-driven non-small cell lung cancer (NSCLC) and is considered as a key target of molecular targeted therapy. EGFR tyrosine kinase inhibitors (TKIs) have been canonically used in NSCLC treatment. However, prevalent innate and acquired resistances and EGFR kinase-independent pro-survival properties limit the clinical efficacy of EGFR TKIs. Therefore, the discovery of novel EGFR degraders is a promising approach towards improving therapeutic efficacy and overcoming drug resistance. Here, we identified a 23-hydroxybetulinic acid derivative, namely DPBA, as a novel EGFR small-molecule ligand. It exerted potent in vitro and in vivo anticancer activity in both EGFR wild type and mutant NSCLC by degrading EGFR. Mechanistic studies disclosed that DPBA binds to the EGFR extracellular domain at sites differing from those of EGF and EGFR. DPBA did not induce EGFR dimerization, phosphorylation, and ubiquitination, but it significantly promoted EGFR degradation and repressed downstream survival pathways. Further analyses showed that DPBA induced clathrin-independent EGFR endocytosis mediated by flotillin-dependent lipid rafts and unaffected by EGFR TKIs. Activation of the early and late endosome markers rab5 and rab7 but not the recycling endosome marker rab11 was involved in DPBA-induced EGFR lysosomal degradation. The present study offers a new EGFR ligand for EGFR pharmacological degradation and proposes it as a potential treatment for EGFR-positive NSCLC, particularly NSCLC with innate or acquired EGFR TKI resistance. DPBA can also serve as a chemical probe in the studies on EGFR trafficking and degradation.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Neoplasm Proteins , Proteolysis/drug effects , Triterpenes , A549 Cells , Animals , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/enzymology , Carcinoma, Non-Small-Cell Lung/genetics , Drug Discovery , ErbB Receptors/agonists , ErbB Receptors/genetics , ErbB Receptors/metabolism , HCT116 Cells , HEK293 Cells , HT29 Cells , Hep G2 Cells , Humans , Ligands , Lung Neoplasms/drug therapy , Lung Neoplasms/enzymology , Lung Neoplasms/genetics , MCF-7 Cells , Male , Mice , Mice, Inbred NOD , Mice, Nude , Mice, SCID , Neoplasm Proteins/agonists , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Triterpenes/chemistry , Triterpenes/pharmacologyABSTRACT
Ovarian cancer remains the leading cause of mortality among gynecological tumors. Estrogen receptor beta (ERß) expression has been suggested to act as a tumor suppressor in epithelial ovarian cancer by reducing both tumor growth and metastasis. ERß expression abnormalities represent a critical step in the development and progression of ovarian cancer: for these reasons, its re-expression by genetic engineering, as well as the use of targeted ERß therapies, still constitute an important therapeutic approach. 3-{[2-chloro-1-(4-chlorobenzyl)-5-methoxy-6-methyl-1H-indol-3-yl]methylene}-5-hydroxy-6-methyl-1,3-dihydro-2H-indol-2-one, referred to here as compound 3, has been shown to have cytostatic as well cytotoxic effects on various hormone-dependent cancer cell lines. However, the mechanism of its anti-carcinogenic activity is not well understood. Here, we offer a possible explanation of such an effect in the human ovarian cancer cell line IGROV1. Chromatin binding protein assay and liquid chromatography mass spectrometry were exploited to localize and quantify compound 3 in cells. Molecular docking was used to prove compound 3 binding to ERß. Mass spectrometry-based approaches were used to analyze histone post-translational modifications. Finally, gene expression analyses revealed a set of genes regulated by the ERß/3 complex, namely CCND1, MYC, CDKN2A, and ESR2, providing possible molecular mechanisms that underline the observed antiproliferative effects.
Subject(s)
Estrogen Receptor beta , Gene Expression Regulation, Neoplastic/drug effects , Indoles , Molecular Docking Simulation , Neoplasm Proteins , Ovarian Neoplasms/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Estrogen Receptor beta/agonists , Estrogen Receptor beta/chemistry , Estrogen Receptor beta/metabolism , Female , Humans , Indoles/chemistry , Indoles/pharmacology , Neoplasm Proteins/agonists , Neoplasm Proteins/chemistry , Neoplasm Proteins/metabolism , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathologyABSTRACT
Background: The frequent overexpression of gastrin-releasing peptide receptors (GRPRs) in human cancers provides the rationale for delivering clinically useful radionuclides to tumor sites using peptide carriers. Radiolabeled GRPR antagonists, besides being safer for human use, have often shown higher tumor uptake and faster background clearance than agonists. We herein compared the biological profiles of the GRPR-antagonist-based radiotracers [99mTc]Tc-[N4-PEGx-DPhe6,Leu-NHEt13]BBN(6-13) (N4: 6-(carboxy)-1,4,8,11-tetraazaundecane; PEG: polyethyleneglycol): (i) [99mTc]Tc-DB7 (x = 2), (ii) [99mTc]Tc-DB13 (x = 3), and (iii) [99mTc]Tc-DB14 (x = 4), in GRPR-positive cells and animal models. The impact of in situ neprilysin (NEP)-inhibition on in vivo stability and tumor uptake was also assessed by treatment of mice with phosphoramidon (PA). Methods: The GRPR affinity of DB7/DB13/DB14 was determined in PC-3 cell membranes, and cell binding of the respective [99mTc]Tc-radioligands was assessed in PC-3 cells. Each of [99mTc]Tc-DB7, [99mTc]Tc-DB13, and [99mTc]Tc-DB14 was injected into mice without or with PA coinjection and 5 min blood samples were analyzed by HPLC. Biodistribution was conducted at 4 h postinjection (pi) in severe combined immunodeficiency disease (SCID) mice bearing PC-3 xenografts without or with PA coinjection. Results: DB7, -13, and -14 displayed single-digit nanomolar affinities for GRPR. The uptake rates of [99mTc]Tc-DB7, [99mTc]Tc-DB13, and [99mTc]Tc-DB14 in PC-3 cells was comparable and consistent with a radioantagonist profile. The radiotracers were found to be ≈70% intact in mouse blood and >94% intact after coinjection of PA. Treatment of mice with PA enhanced tumor uptake. Conclusions: The present study showed that increase of PEG-spacer length in the [99mTc]Tc-DB7-[99mTc]Tc-DB13-[99mTc]Tc-DB14 series had little effect on GRPR affinity, specific uptake in PC-3 cells, in vivo stability, or tumor uptake. A significant change in in vivo stability and tumor uptake was observed only after treatment of mice with PA, without compromising the favorably low background radioactivity levels.
Subject(s)
Antineoplastic Agents , Biomimetic Materials , Neoplasm Proteins , Organotechnetium Compounds , Peptides , Prostatic Neoplasms , Receptors, Bombesin , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Humans , Male , Mice , Mice, SCID , Neoplasm Proteins/agonists , Neoplasm Proteins/metabolism , Organotechnetium Compounds/chemistry , Organotechnetium Compounds/pharmacology , PC-3 Cells , Peptides/chemistry , Peptides/pharmacology , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Receptors, Bombesin/agonists , Receptors, Bombesin/metabolism , Xenograft Model Antitumor AssaysABSTRACT
Cytosolic DNA sensing, the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway, is an important novel role in the immune system. Multiple STING agonists were developed for cancer therapy study with great results achieved in pre-clinical work. Recent progress in the mechanical understanding of STING pathway in IFN production and T cell priming, indicates its promising role for cancer immunotherapy. STING agonists co-administrated with other cancer immunotherapies, including cancer vaccines, immune checkpoint inhibitors such as anti-programmed death 1 and cytotoxic T lymphocyte-associated antigen 4 antibodies, and adoptive T cell transfer therapies, would hold a promise of treating medium and advanced cancers. Despite the applications of STING agonists in cancer immunotherapy, lots of obstacles remain for further study. In this review, we mainly examine the biological characters, current applications, challenges, and future directions of cGAS-STING in cancer immunotherapy.
Subject(s)
Immunotherapy , Membrane Proteins/agonists , Neoplasm Proteins/agonists , Neoplasms/therapy , Nucleotides, Cyclic/physiology , Signal Transduction/drug effects , Adenylyl Cyclases/physiology , Adjuvants, Immunologic , Animals , CTLA-4 Antigen/antagonists & inhibitors , Cancer Vaccines/immunology , Cancer Vaccines/therapeutic use , Clinical Trials as Topic , DNA/metabolism , DNA, Neoplasm/metabolism , Drug Screening Assays, Antitumor , Humans , Immune Checkpoint Inhibitors/therapeutic use , Immunotherapy, Adoptive , Membrane Proteins/chemistry , Membrane Proteins/physiology , Mice , Neoplasm Proteins/chemistry , Neoplasm Proteins/physiology , Neoplasms/immunology , Oncolytic Virotherapy , Protein Multimerization , Therapies, InvestigationalABSTRACT
Although the B-cell translocation gene 1 (BTG1) plays an important role in apoptosis and negatively regulates cell proliferation, BTG1 expression in skin squamous cell carcinoma (SCC) has not been reported. In this study, we wanted to investigate the significance of BTG1 expression in SCC and adjacent tissues. The expression of BTG1 protein and mRNA in SCC tissues and adjacent tissues were detected by immunohistochemistry technique (IHC), Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). IHC staining showed that the positive expression rate of BTG1 protein in SCC tissues was 54.00%; and the positive rate was 90.50% in the adjacent tissues. Western blot showed that the expression of BTG1 protein in SCC tissues was significantly lower than that in the adjacent tissues (P less than 0.05). RT-PCR showed that the positive rate of BTG1 mRNA in SCC was 50.50%, which was significantly lower than that in adjacent tissues 89.00% (P less than 0.05). Both BTG1 mRNA and protein expression are related to tumor diameter, stage, tumor metastasis and the degree of tumor differentiation in SCC. Patients exhibiting lower BTG1 protein expression in the SCC tissues had a significantly shorter disease-specific survival rate. BTG1 protein expression, tumor diameter, tumors site and stage were independent factors affecting the overall survival of postoperative patients. Further, BTG1 overexpression inhibited A431 cell proliferation ability, while BTG silencing enhanced A431 cell proliferation ability. The lower expression of BTG1 in SCC may be associated with the occurrence, development and prognosis of SCC.
Subject(s)
Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/genetics , Gene Expression Regulation, Neoplastic , Neoplasm Proteins/genetics , Skin Neoplasms/diagnosis , Skin Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Apoptosis/genetics , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Case-Control Studies , Cell Line, Tumor , Cell Proliferation , Female , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Proteins/agonists , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/metabolism , Neoplasm Staging , Oligoribonucleotides/genetics , Oligoribonucleotides/metabolism , Prognosis , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Skin Neoplasms/mortality , Skin Neoplasms/pathology , Survival AnalysisABSTRACT
Multifunctional nanomaterials with targeted imaging and chemotherapy have high demand with great challenge. Herein, we rationally aimed to design multifunctional drug delivery systems by RGD-modified chitosan (CH)-coated nanoneedles (NDs) of gadolinium arsenate (RGD-CH-Gd-AsNDs). These NDs have multifunctionality for imaging and targeted therapy. NDs on intravenous administration demonstrated significant accumulation of As ions/species in tumor tissues, which was monitored by the change in T1-weighted magnetic resonance (MR) imaging. Moreover, NDs were well opsonized in cells with high specificity, subsequently inducing apoptosis to the HepG2 cells. Consequent to this, the in vivo results demonstrated biosafety, enhanced tumor targeting, and tumor regression in a subcutaneously transplanted xenograft model in nude mice. These RGD-CH-Gd-AsNDs have great potential, and we anticipate that they could serve as a novel platform for real-time T1-weighted MR diagnosis and chemotherapy.
Subject(s)
Arsenates , Chitosan , Gadolinium , Integrin alphaVbeta3/agonists , Liver Neoplasms, Experimental , Magnetic Resonance Imaging , Nanostructures , Neoplasm Proteins/agonists , Oligopeptides , Animals , Arsenates/chemistry , Arsenates/pharmacology , Chitosan/chemistry , Chitosan/pharmacology , Gadolinium/chemistry , Gadolinium/pharmacology , Hep G2 Cells , Humans , Integrin alphaVbeta3/metabolism , Liver Neoplasms, Experimental/diagnostic imaging , Liver Neoplasms, Experimental/drug therapy , Mice , Mice, Inbred BALB C , Mice, Nude , Nanostructures/chemistry , Nanostructures/therapeutic use , Neoplasm Proteins/metabolism , Oligopeptides/chemistry , Oligopeptides/pharmacologyABSTRACT
Here, we report various therapeutic cargo-loadable DNA nanostructures that are shelled in polydopamine and noncovalently tethered with cancer cell-targeting DNA aptamers. Initial DNA nanostructure was formed by rolling-circle amplification and condensation with Mu peptides. This DNA nanostructure was loaded with an antisense oligonucleotide, a photosensitizer, or an anticancer chemotherapeutic drug. Each therapeutic agent-loaded DNA nanostructure was then shelled with polydopamine (PDA), and noncovalently decorated with a poly adenine-tailed nucleic acid aptamer (PA) specific for PTK7 receptor, resulting in PA-tethered and PDA-shelled DNA nanostructure (PA/PDN). PDA coating shell enabled photothermal therapy. In the cells overexpressing PTK7 receptor, photosensitizer-loaded PA/PDN showed greater photodynamic activity. Doxorubicin-loaded PA/PDN exerted higher anticancer activity than the other groups. Antisense oligonucleotide-loaded PA/PDN provided selective reduction of target proteins compared with other groups. Our results suggest that the PA-tethered and PDA-shelled DNA nanostructures could enable the specific receptor-targeted phototherapy, chemotherapy, and gene therapy against cancer cells.
Subject(s)
Aptamers, Nucleotide , Genetic Therapy , Hyperthermia, Induced , Neoplasms , Phototherapy , Aptamers, Nucleotide/chemistry , Aptamers, Nucleotide/pharmacology , Cell Adhesion Molecules/agonists , Cell Adhesion Molecules/metabolism , Cell Line, Tumor , Humans , Nanostructures/chemistry , Nanostructures/therapeutic use , Neoplasm Proteins/agonists , Neoplasm Proteins/metabolism , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms/therapy , Receptor Protein-Tyrosine Kinases/agonists , Receptor Protein-Tyrosine Kinases/metabolismABSTRACT
TMEM16A (anoctamin 1) is an important calcium-activated chloride channel in airway smooth muscle (ASM). We have previously shown that TMEM16A antagonists such as benzbromarone relax ASM and have proposed TMEM16A antagonists as novel therapies for asthma treatment. However, TMEM16A is also expressed on airway epithelium, and TMEM16A agonists are being investigated as novel therapies for cystic fibrosis. There are theoretical concerns that agonism of TMEM16A on ASM could lead to bronchospasm, making them detrimental as airway therapeutics. The TMEM16A agonist Eact induced a significant contraction of human ASM and guinea pig tracheal rings in an ex vivo organ bath model. Pretreatment with two different TMEM16A antagonists, benzbromarone or T16Ainh-A01, completely attenuated these Eact-induced contractions. Pretreatment with Eact alone augmented the maximum acetylcholine contraction. Pretreatment of A/J mice in vivo with nebulized Eact caused an augmentation of methacholine-induced increases in airway resistance measured by the forced oscillatory technique (flexiVent). Pretreatment with the TMEM16A antagonist benzbromarone significantly attenuated methacholine-induced increases in airway resistance. In in vitro cellular studies, TMEM16A was found to be expressed more abundantly in ASM compared with epithelial cells in culture (8-fold higher in ASM). Eact caused an increase in intracellular calcium in human ASM cells that was completely attenuated by pretreatment with benzbromarone. Eact acutely depolarized the plasma membrane potential of ASM cells, which was attenuated by benzbromarone or nifedipine. The TMEM16A agonist Eact modulates ASM contraction in both ex vivo and in vivo models, suggesting that agonism of TMEM16A may lead to clinically relevant bronchospasm.