Engineering of Systematic Elimination of a Targeted Chromosome in Human Cells.

PubMed

Sato, Hiroshi; Kato, Hiroki; Yamaza, Haruyoshi; Masuda, Keiji; Nguyen, Huong Thi Nguyen; Pham, Thanh Thi Mai; Han, Xu; Hirofuji, Yuta; Nonaka, Kazuaki

2017-01-01

Embryonic trisomy leads to abortion or congenital genetic disorders in humans. The most common autosomal chromosome abnormalities are trisomy of chromosomes 13, 18, and 21. Although alteration of gene dosage is thought to contribute to disorders caused by extra copies of chromosomes, genes associated with specific disease phenotypes remain unclear. To generate a normal cell from a trisomic cell as a means of etiological analysis or candidate therapy for trisomy syndromes, we developed a system to eliminate a targeted chromosome from human cells. Chromosome 21 was targeted by integration of a DNA cassette in HeLa cells that harbored three copies of chromosome 21. The DNA cassette included two inverted loxP sites and a herpes simplex virus thymidine kinase (HSV-tk) gene. This system causes missegregation of chromosome 21 after expression of Cre recombinase and subsequently enables the selection of cells lacking the chromosome by culturing in a medium that includes ganciclovir (GCV). Cells harboring only two copies of chromosome 21 were efficiently induced by transfection of a Cre expression vector, indicating that this approach is useful for eliminating a targeted chromosome.

Cancer stem cell-targeted therapeutics and delivery strategies.

PubMed

Ahmad, Gulzar; Amiji, Mansoor M

2017-08-01

Cancer initiating or stem cells (CSCs) are a small population of cells in the tumor mass, which have been reported to be present in different types of cancers. CSCs usually reside within the tumor and are responsible for reoccurrence of cancer. The imprecise, inaccessible nature and increased efflux of conventional therapeutic drugs make these cells resistant to drugs. We discuss the specific markers for identification of these cells, role of CSCs in chemotherapy resistance and use of different therapeutic means to target them, including elucidation of specific cell markers, exploitation of different signaling pathways and use of nanotechnology. Area covered: This review covers cancer stem cell signaling which are used by these cells to maintain their quiescence, stemness and resistant phenotype, distinct cell surface markers, contribution of these cells in drug resistance, inevitability to cure cancer and use of nanotechnology to overcome this hurdle. Expert opinion: Cancer stem cells are the main culprit of our failure to cure cancer. In order to cure cancer along with other cells types in cancer, cancer stem cells need to be targeted in the tumor bed. Nanotechnology solutions can facilitate clinical translation of the therapeutics along with other emerging technologies to cure cancer.

Pro-Tumoral Inflammatory Myeloid Cells as Emerging Therapeutic Targets.

PubMed

Szebeni, Gabor J; Vizler, Csaba; Nagy, Lajos I; Kitajka, Klara; Puskas, Laszlo G

2016-11-23

Since the observation of Virchow, it has long been known that the tumor microenvironment constitutes the soil for the infiltration of inflammatory cells and for the release of inflammatory mediators. Under certain circumstances, inflammation remains unresolved and promotes cancer development. Here, we review some of these indisputable experimental and clinical evidences of cancer related smouldering inflammation. The most common myeloid infiltrate in solid tumors is composed of myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). These cells promote tumor growth by several mechanisms, including their inherent immunosuppressive activity, promotion of neoangiogenesis, mediation of epithelial-mesenchymal transition and alteration of cellular metabolism. The pro-tumoral functions of TAMs and MDSCs are further enhanced by their cross-talk offering a myriad of potential anti-cancer therapeutic targets. We highlight these main pro-tumoral mechanisms of myeloid cells and give a general overview of their phenotypical and functional diversity, offering examples of possible therapeutic targets. Pharmacological targeting of inflammatory cells and molecular mediators may result in therapies improving patient condition and prognosis. Here, we review experimental and clinical findings on cancer-related inflammation with a major focus on creating an inventory of current small molecule-based therapeutic interventions targeting cancer-related inflammatory cells: TAMs and MDSCs.

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

PubMed

Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

Cell targeting peptides as smart ligands for targeting of therapeutic or diagnostic agents: a systematic review.

PubMed

Mousavizadeh, Ali; Jabbari, Ali; Akrami, Mohammad; Bardania, Hassan

2017-10-01

Cell targeting peptides (CTP) are small peptides which have high affinity and specificity to a cell or tissue targets. They are typically identified by using phage display and chemical synthetic peptide library methods. CTPs have attracted considerable attention as a new class of ligands to delivery specifically therapeutic and diagnostic agents, because of the fact they have several advantages including easy synthesis, smaller physical sizes, lower immunogenicity and cytotoxicity and their simple and better conjugation to nano-carriers and therapeutic or diagnostic agents compared to conventional antibodies. In this systematic review, we will focus on the basic concepts concerning the use of cell-targeting peptides (CTPs), following the approaches of selecting them from peptide libraries. We discuss several developed strategies for cell-specific delivery of different cargos by CTPs, which are designed for drug delivery and diagnostic applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Detecting drug-target binding in cells using fluorescence-activated cell sorting coupled with mass spectrometry analysis.

PubMed

Wilson, Kris; Webster, Scott P; Iredale, John P; Zheng, Xiaozhong; Homer, Natalie Z; Pham, Nhan T; Auer, Manfred; Mole, Damian J

2017-12-15

The assessment of drug-target engagement for determining the efficacy of a compound inside cells remains challenging, particularly for difficult target proteins. Existing techniques are more suited to soluble protein targets. Difficult target proteins include those with challenging in vitro solubility, stability or purification properties that preclude target isolation. Here, we report a novel technique that measures intracellular compound-target complex formation, as well as cellular permeability, specificity and cytotoxicity-the toxicity-affinity-permeability-selectivity (TAPS) technique. The TAPS assay is exemplified here using human kynurenine 3-monooxygenase (KMO), a challenging intracellular membrane protein target of significant current interest. TAPS confirmed target binding of known KMO inhibitors inside cells. We conclude that the TAPS assay can be used to facilitate intracellular hit validation on most, if not all intracellular drug targets.

Detecting drug-target binding in cells using fluorescence-activated cell sorting coupled with mass spectrometry analysis

NASA Astrophysics Data System (ADS)

Wilson, Kris; Webster, Scott P.; Iredale, John P.; Zheng, Xiaozhong; Homer, Natalie Z.; Pham, Nhan T.; Auer, Manfred; Mole, Damian J.

2018-01-01

The assessment of drug-target engagement for determining the efficacy of a compound inside cells remains challenging, particularly for difficult target proteins. Existing techniques are more suited to soluble protein targets. Difficult target proteins include those with challenging in vitro solubility, stability or purification properties that preclude target isolation. Here, we report a novel technique that measures intracellular compound-target complex formation, as well as cellular permeability, specificity and cytotoxicity-the toxicity-affinity-permeability-selectivity (TAPS) technique. The TAPS assay is exemplified here using human kynurenine 3-monooxygenase (KMO), a challenging intracellular membrane protein target of significant current interest. TAPS confirmed target binding of known KMO inhibitors inside cells. We conclude that the TAPS assay can be used to facilitate intracellular hit validation on most, if not all intracellular drug targets.

The therapeutic potential of cell cycle targeting in multiple myeloma.

PubMed

Maes, Anke; Menu, Eline; Veirman, Kim De; Maes, Ken; Vand Erkerken, Karin; De Bruyne, Elke

2017-10-27

Proper cell cycle progression through the interphase and mitosis is regulated by coordinated activation of important cell cycle proteins (including cyclin-dependent kinases and mitotic kinases) and several checkpoint pathways. Aberrant activity of these cell cycle proteins and checkpoint pathways results in deregulation of cell cycle progression, which is one of the key hallmarks of cancer. Consequently, intensive research on targeting these cell cycle regulatory proteins identified several candidate small molecule inhibitors that are able to induce cell cycle arrest and even apoptosis in cancer cells. Importantly, several of these cell cycle regulatory proteins have also been proposed as therapeutic targets in the plasma cell malignancy multiple myeloma (MM). Despite the enormous progress in the treatment of MM the past 5 years, MM still remains most often incurable due to the development of drug resistance. Deregulated expression of the cyclins D is observed in virtually all myeloma patients, emphasizing the potential therapeutic interest of cyclin-dependent kinase inhibitors in MM. Furthermore, other targets have also been identified in MM, such as microtubules, kinesin motor proteins, aurora kinases, polo-like kinases and the anaphase promoting complex/cyclosome. This review will provide an overview of the cell cycle proteins and checkpoint pathways deregulated in MM and discuss the therapeutic potential of targeting proteins or protein complexes involved in cell cycle control in MM.

Targeting Notch signalling pathway of cancer stem cells.

PubMed

Venkatesh, Vandana; Nataraj, Raghu; Thangaraj, Gopenath S; Karthikeyan, Murugesan; Gnanasekaran, Ashok; Kaginelli, Shanmukhappa B; Kuppanna, Gobianand; Kallappa, Chandrashekrappa Gowdru; Basalingappa, Kanthesh M

2018-01-01

Cancer stem cells (CSCs) have been defined as cells within tumor that possess the capacity to self-renew and to cause the heterogeneous lineages of cancer cells that comprise the tumor. CSCs have been increasingly identified in blood cancer, prostate, ovarian, lung, melanoma, pancreatic, colon, brain and many more malignancies. CSCs have slow growth rate and are resistant to chemotherapy and radiotherapy that lead to the failure of traditional current therapy. Eradicating the CSCs and recurrence, is promising aspect for the cure of cancer. The CSCs like any other stem cells activate the signal transduction pathways that involve the development and tissue homeostasis, which include Notch signaling pathway. The new treatment targets these pathway that control stem-cell replication, survival and differentiation that are under development. Notch inhibitors either single or in combination with chemotherapy drugs have been developed to treat cancer and its recurrence. This approach of targeting signaling pathway of CSCs represents a promising future direction for the therapeutic strategy to cure cancer.

Human immune cell targeting of protein nanoparticles - caveospheres

NASA Astrophysics Data System (ADS)

Glass, Joshua J.; Yuen, Daniel; Rae, James; Johnston, Angus P. R.; Parton, Robert G.; Kent, Stephen J.; de Rose, Robert

2016-04-01

Nanotechnology has the power to transform vaccine and drug delivery through protection of payloads from both metabolism and off-target effects, while facilitating specific delivery of cargo to immune cells. However, evaluation of immune cell nanoparticle targeting is conventionally restricted to monocultured cell line models. We generated human caveolin-1 nanoparticles, termed caveospheres, which were efficiently functionalized with monoclonal antibodies. Using this platform, we investigated CD4+ T cell and CD20+ B cell targeting within physiological mixtures of primary human blood immune cells using flow cytometry, imaging flow cytometry and confocal microscopy. Antibody-functionalization enhanced caveosphere binding to targeted immune cells (6.6 to 43.9-fold) within mixed populations and in the presence of protein-containing fluids. Moreover, targeting caveospheres to CCR5 enabled caveosphere internalization by non-phagocytic CD4+ T cells--an important therapeutic target for HIV treatment. This efficient and flexible system of immune cell-targeted caveosphere nanoparticles holds promise for the development of advanced immunotherapeutics and vaccines.

Folate-conjugated immunoglobulin targets melanoma tumor cells for NK cell effector functions

PubMed Central

Skinner, Cassandra C.; McMichael, Elizabeth L.; Jaime-Ramirez, Alena C.; Abrams, Zachary B.; Lee, Robert J.; Carson, William E.

2016-01-01

The folate receptor (FR) is over-expressed on the vascular side of cancerous cells including those of the breast, ovaries, testes, and cervix. We hypothesized that a folate-conjugated immunoglobulin (F-IgG) would bind to the FR that is over-expressed on melanoma tumor cells to target these cells for lysis by natural killer (NK) cells. Folate receptor expression was confirmed in the Mel-39 (human melanoma) cell line by flow cytometry and immunoblot analysis, using KB (human oral epithelial) and F01 (human melanoma) as a positive and negative control, respectively. FR-positive and negative cell lines were treated with F-IgG or control immunoglobulin G (C-IgG) in the presence or absence of cytokines in order to determine NK cell ability to lyse FR-positive cell lines. NK cell activation was significantly upregulated and lysis of Mel 39 tumor cells enhanced following treatment with F-IgG, as compared to C-IgG at all effector:target (E:T) ratios (p<0.01). This trend was further enhanced by NK cell stimulation with the activating cytokine interleukin-12 (IL-12). NK cell production of cytokines such as interferon-gamma (IFN-γ), macrophage inflammatory protein 1 alpha (MIP-1α), and regulated on activation normal T-cell expressed and secreted (RANTES) were also significantly increased in response to co-stimulation with IL-12 stimulation and F-IgG-coated Mel 39 target cells, as compared to controls (p<0.01). In contrast, F-IgG did not bind to the FR-negative cell line F01 and had no significant effect on NK cell lysis or cytokine production. This research indicates the potential use of F-IgG for its ability to induce an immune response from NK cells against FR-positive melanoma tumor cells which can be further enhanced by the addition of cytokines. PMID:27035691

Pharmacological targets of breast cancer stem cells: a review.

PubMed

Pindiprolu, Sai Kiran S S; Krishnamurthy, Praveen T; Chintamaneni, Pavan Kumar

2018-05-01

Breast cancers contain small population of tumor-initiating cells called breast cancer stem cells (BCSCs), which are spared even after chemotherapy. Recently, BCSCs are implicated to be a cause of metastasis, tumor relapse, and therapy resistance in breast cancer. BCSCs have unique molecular mechanisms, which can be targeted to eliminate them. These include surface biomarkers, proteins involved in self-renewal pathways, drug efflux transporters, apoptotic/antiapoptotic proteins, autophagy, metabolism, and microenvironment regulation. The complex molecular mechanisms behind the survival of BCSCs and pharmacological targets for elimination of BCSCs are described in this review.

Targeting survival pathways in chronic myeloid leukaemia stem cells

PubMed Central

Sinclair, A; Latif, A L; Holyoake, T L

2013-01-01

Chronic myeloid leukaemia (CML) is a clonal myeloproliferative disorder characterized by the presence of a fusion oncogene BCR-ABL, which encodes a protein with constitutive TK activity. The implementation of tyrosine kinase inhibitors (TKIs) marked a major advance in CML therapy; however, there are problems with current treatment. For example, relapse occurs when these drugs are discontinued in the majority of patients who have achieved a complete molecular response on TKI and these agents are less effective in patients with mutations in the BCR-ABL kinase domain. Importantly, TKI can effectively target proliferating mature cells, but do not eradicate quiescent leukaemic stem cells (LSCs), therefore allowing disease persistence despite treatment. It is essential that alternative strategies are used to target the LSC population. BCR-ABL activation is responsible for the modulation of different signalling pathways, which allows the LSC fraction to evade cell death. Several pathways have been shown to be modulated by BCR-ABL, including PI3K/AKT/mTOR, JAK-STAT and autophagy signalling pathways. Targeting components of these survival pathways, alone or in combination with TKI, therefore represents an attractive potential therapeutic approach for targeting the LSC. However, many pathways are also active in normal stem cells. Therefore, potential targets must be validated to effectively eradicate CML stem cells while sparing normal counterparts. This review summarizes the main pathways modulated in CML stem cells, the recent developments and the use of novel drugs to target components in these pathways which may be used to target the LSC population. Linked Articles This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8 PMID:23517124

[Therapeutic strategies targeting brain tumor stem cells].

PubMed

Toda, Masahiro

2009-07-01

Progress in stem cell research reveals cancer stem cells to be present in a variety of malignant tumors. Since they exhibit resistance to anticancer drugs and radiotherapy, analysis of their properties has been rapidly carried forward as an important target for the treatment of intractable malignancies, including brain tumors. In fact, brain cancer stem cells (BCSCs) have been isolated from brain tumor tissue and brain tumor cell lines by using neural stem cell culture methods and isolation methods for side population (SP) cells, which have high drug-efflux capacity. Although the analysis of the properties of BCSCs is the most important to developing methods in treating BCSCs, the absence of BCSC purification methods should be remedied by taking it up as an important research task in the immediate future. Thus far, there are no effective treatment methods for BCSCs, and several treatment methods have been proposed based on the cell biology characteristics of BCSCs. In this article, I outline potential treatment methods damaging treatment-resistant BCSCs, including immunotherapy which is currently a topic of our research.

Cell-specific targeting by heterobivalent ligands.

PubMed

Josan, Jatinder S; Handl, Heather L; Sankaranarayanan, Rajesh; Xu, Liping; Lynch, Ronald M; Vagner, Josef; Mash, Eugene A; Hruby, Victor J; Gillies, Robert J

2011-07-20

Current cancer therapies exploit either differential metabolism or targeting to specific individual gene products that are overexpressed in aberrant cells. The work described herein proposes an alternative approach--to specifically target combinations of cell-surface receptors using heteromultivalent ligands ("receptor combination approach"). As a proof-of-concept that functionally unrelated receptors can be noncovalently cross-linked with high avidity and specificity, a series of heterobivalent ligands (htBVLs) were constructed from analogues of the melanocortin peptide ligand ([Nle(4), dPhe(7)]-α-MSH) and the cholecystokinin peptide ligand (CCK-8). Binding of these ligands to cells expressing the human Melanocortin-4 receptor and the Cholecystokinin-2 receptor was analyzed. The MSH(7) and CCK(6) were tethered with linkers of varying rigidity and length, constructed from natural and/or synthetic building blocks. Modeling data suggest that a linker length of 20-50 Å is needed to simultaneously bind these two different G-protein coupled receptors (GPCRs). These ligands exhibited up to 24-fold enhancement in binding affinity to cells that expressed both (bivalent binding), compared to cells with only one (monovalent binding) of the cognate receptors. The htBVLs had up to 50-fold higher affinity than that of a monomeric CCK ligand, i.e., Ac-CCK(6)-NH(2). Cell-surface targeting of these two cell types with labeled heteromultivalent ligand demonstrated high avidity and specificity, thereby validating the receptor combination approach. This ability to noncovalently cross-link heterologous receptors and target individual cells using a receptor combination approach opens up new possibilities for specific cell targeting in vivo for therapy or imaging.

Cell-Specific Targeting by Heterobivalent Ligands

PubMed Central

Josan, Jatinder S.; Handl, Heather L.; Sankaranarayanan, Rajesh; Xu, Liping; Lynch, Ronald M.; Vagner, Josef; Mash, Eugene A.; Hruby, Victor J.; Gillies, Robert J.

2012-01-01

Current cancer therapies exploit either differential metabolism or targeting to specific individual gene products that are overexpressed in aberrant cells. The work described herein proposes an alternative approach—to specifically target combinations of cell-surface receptors using heteromultivalent ligands (“receptor combination approach”). As a proof-of-concept that functionally unrelated receptors can be noncovalently cross-linked with high avidity and specificity, a series of heterobivalent ligands (htBVLs) were constructed from analogues of the melanocortin peptide ligand ([Nle4, DPhe7]-α-MSH) and the cholecystokinin peptide ligand (CCK-8). Binding of these ligands to cells expressing the human Melanocortin-4 receptor and the Cholecystokinin-2 receptor was analyzed. The MSH(7) and CCK(6) were tethered with linkers of varying rigidity and length, constructed from natural and/or synthetic building blocks. Modeling data suggest that a linker length of 20–50 Å is needed to simultaneously bind these two different G-protein coupled receptors (GPCRs). These ligands exhibited up to 24-fold enhancement in binding affinity to cells that expressed both (bivalent binding), compared to cells with only one (monovalent binding) of the cognate receptors. The htBVLs had up to 50-fold higher affinity than that of a monomeric CCK ligand, i.e., Ac-CCK(6)-NH2. Cell-surface targeting of these two cell types with labeled heteromultivalent ligand demonstrated high avidity and specificity, thereby validating the receptor combination approach. This ability to noncovalently cross-link heterologous receptors and target individual cells using a receptor combination approach opens up new possibilities for specific cell targeting in vivo for therapy or imaging. PMID:21639139

Zn(II)-curc targets p53 in thyroid cancer cells.

PubMed

Garufi, Alessia; D'Orazi, Valerio; Crispini, Alessandra; D'Orazi, Gabriella

2015-10-01

TP53 mutation is a common event in many cancers, including thyroid carcinoma. Defective p53 activity promotes cancer resistance to therapies and a more malignant phenotype, acquiring oncogenic functions. Rescuing the function of mutant p53 (mutp53) protein is an attractive anticancer therapeutic strategy. Zn(II)-curc is a novel small molecule that has been shown to target mutp53 protein in several cancer cells, but its effect in thyroid cancer cells remains unclear. Here, we investigated whether Zn(II)-curc could affect p53 in thyroid cancer cells with both p53 mutation (R273H) and wild-type p53. Zn(II)-curc induced mutp53H273 downregulation and reactivation of wild-type functions, such as binding to canonical target promoters and target gene transactivation. This latter effect was similar to that induced by PRIMA-1. In addition, Zn(II)-curc triggered p53 target gene expression in wild-type p53-carrying cells. In combination treatments, Zn(II)-curc enhanced the antitumor activity of chemotherapeutic drugs, in both mutant and wild-type-carrying cancer cells. Taken together, our data indicate that Zn(II)-curc promotes the reactivation of p53 in thyroid cancer cells, providing in vitro evidence for a potential therapeutic approach in thyroid cancers.

Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells

DTIC Science & Technology

2016-10-01

AWARD NUMBER: W81XWH-15-1-0644 TITLE: Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells PRINCIPAL INVESTIGATOR: Chun-Ju...U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 DISTRIBUTION STATEMENT: Approved for Public Release...Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-0644 5c. PROGRAM ELEMENT

A hypothesis of target cell formation in sickle cell disease.

PubMed

Wong, P

2016-08-01

A fraction of erythrocytes appear as target cells in stained blood smears in sickle cell disease, due to a inheritance of the hemoglobin variant Hb S, polymerizing upon deoxygenation. These cells appear in a three dimension as thin cups. A process of their formation in this disease is proposed based on a band 3-based mechanism of the erythrocyte shape control, able to explain the erythrocyte echinocytosis by glucose depletion. It indicates that their formation is due to a stomatocytogenic slow outward transport of the dibasic form of endogenous Pi with an H(+) by band 3, promoted by the decrease of the Donnan ratio, which decreases cell pH and volume, attributed by a decrease of cell KCl concentration by the higher efflux of K(+)Cl(-) cotransport and Ca(2+) activation of the Gardos channel. Its implications are briefly discussed with respect to target cells per se, target cell formation in other hemoglobinopathies, acquired and inherited disorders of the lipid metabolism and dehydrated hereditary stomatocytosis as well as a stomatocyte presence in a double heterozygote of Hb S and Hb C and of an involvement of the process of target cell formation in acanthocytosis in acquired and inherited disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evolving phage vectors for cell targeted gene delivery.

PubMed

Larocca, David; Burg, Michael A; Jensen-Pergakes, Kristen; Ravey, Edward Prenn; Gonzalez, Ana Maria; Baird, Andrew

2002-03-01

We adapted filamentous phage vectors for targeted gene delivery to mammalian cells by inserting a mammalian reporter gene expression cassette (GFP) into the vector backbone and fusing the pIII coat protein to a cell targeting ligand (i.e. FGF2, EGF). Like transfection with animal viral vectors, targeted phage gene delivery is concentration, time, and ligand dependent. Importantly, targeted phage particles are specific for the appropriate target cell surface receptor. Phage have distinct advantages over existing gene therapy vectors because they are simple, economical to produce at high titer, have no intrinsic tropism for mammalian cells, and are relatively simple to genetically modify and evolve. Initially transduction by targeted phage particles was low resulting in foreign gene expression in 1-2% of transfected cells. We increased transduction efficiency by modifying both the transfection protocol and vector design. For example, we stabilized the display of the targeting ligand to create multivalent phagemid-based vectors with transduction efficiencies of up to 45% in certain cell lines when combined with genotoxic treatment. Taken together, these studies establish that the efficiency of phage-mediated gene transfer can be significantly improved through genetic modification. We are currently evolving phage vectors with enhanced cell targeting, increased stability, reduced immunogenicity and other properties suitable for gene therapy.

Monoclonal antibodies targeting non-small cell lung cancer stem-like cells by multipotent cancer stem cell monoclonal antibody library.

PubMed

Cao, Kaiyue; Pan, Yunzhi; Yu, Long; Shu, Xiong; Yang, Jing; Sun, Linxin; Sun, Lichao; Yang, Zhihua; Ran, Yuliang

2017-02-01

Cancer stem cells (CSCs) are a rare subset of cancer cells that play a significant role in cancer initiation, spreading, and recurrence. In this study, a subpopulation of lung cancer stem-like cells (LCSLCs) was identified from non-small cell lung carcinoma cell lines, SPCA-1 and A549, using serum-free suspension sphere-forming culture method. A monoclonal antibody library was constructed using immunized BLAB/c mice with the multipotent CSC cell line T3A-A3. Flow cytometry analysis showed that 33 mAbs targeted antigens can be enriched in sphere cells compared with the parental cells of SPCA-1 and A549 cell lines. Then, we performed functional antibody screening including sphere-forming inhibiting and invasion inhibiting assay. The results showed that two antibodies, 12C7 and 9B8, notably suppressed the self-renewal and invasion of LCSLCs. Fluorescence-activated cell sorting (FACs) found that the positive cells recognized by mAbs, 12C7 or 9B8, displayed features of LCSLCs. Interestingly, we found that these two antibodies recognized different subsets of cells and their combination effect was superior to the individual effect both in vitro and in vivo. Tissue microarrays were applied to detect the expression of the antigens targeted by these two antibodies. The positive expression of 12C7 and 9B8 targeted antigen was 84.4 and 82.5%, respectively, which was significantly higher than that in the non-tumor lung tissues. In conclusion, we screened two potential therapeutic antibodies that target different subsets of LCSLCs.

Inhibitors targeting on cell wall biosynthesis pathway of MRSA.

PubMed

Hao, Haihong; Cheng, Guyue; Dai, Menghong; Wu, Qinghua; Yuan, Zonghui

2012-11-01

Methicillin resistant Staphylococcus aureus (MRSA), widely known as a type of new superbug, has aroused world-wide concern. Cell wall biosynthesis pathway is an old but good target for the development of antibacterial agents. Peptidoglycan and wall teichoic acids (WTAs) biosynthesis are two main processes of the cell wall biosynthesis pathway (CWBP). Other than penicillin-binding proteins (PBPs), some key factors (Mur enzymes, lipid I or II precursor, etc.) in CWBP are becoming attractive molecule targets for the discovery of anti-MRSA compounds. A number of new compounds, with higher affinity for PBPs or with inhibitory activity on such molecule targets in CWBP of MRSA, have been in the pipeline recently. This review concludes recent research achievements and provides a complete picture of CWBP of MRSA, including the peptidoglycan and wall teichoic acids synthesis pathway. The potential inhibitors targeting on CWBP are subsequently presented to improve development of novel therapeutic strategies for MRSA.

Statistical Modeling of Single Target Cell Encapsulation

PubMed Central

Moon, SangJun; Ceyhan, Elvan; Gurkan, Umut Atakan; Demirci, Utkan

2011-01-01

High throughput drop-on-demand systems for separation and encapsulation of individual target cells from heterogeneous mixtures of multiple cell types is an emerging method in biotechnology that has broad applications in tissue engineering and regenerative medicine, genomics, and cryobiology. However, cell encapsulation in droplets is a random process that is hard to control. Statistical models can provide an understanding of the underlying processes and estimation of the relevant parameters, and enable reliable and repeatable control over the encapsulation of cells in droplets during the isolation process with high confidence level. We have modeled and experimentally verified a microdroplet-based cell encapsulation process for various combinations of cell loading and target cell concentrations. Here, we explain theoretically and validate experimentally a model to isolate and pattern single target cells from heterogeneous mixtures without using complex peripheral systems. PMID:21814548

Oxidant-induced DNA damage of target cells.

PubMed Central

Schraufstätter, I; Hyslop, P A; Jackson, J H; Cochrane, C G

1988-01-01

In this study we examined the leukocytic oxidant species that induce oxidant damage of DNA in whole cells. H2O2 added extracellularly in micromolar concentrations (10-100 microM) induced DNA strand breaks in various target cells. The sensitivity of a specific target cell was inversely correlated to its catalase content and the rate of removal of H2O2 by the target cell. Oxidant species produced by xanthine oxidase/purine or phorbol myristate acetate-stimulated monocytes induced DNA breakage of target cells in proportion to the amount of H2O2 generated. These DNA strand breaks were prevented by extracellular catalase, but not by superoxide dismutase. Cytotoxic doses of HOCl, added to target cells, did not induce DNA strand breakage, and myeloperoxidase added extracellularly in the presence of an H2O2-generating system, prevented the formation of DNA strand breaks in proportion to its H2O2 degrading capacity. The studies also indicated that H2O2 formed hydroxyl radical (.OH) intracellularly, which appeared to be the most likely free radical responsible for DNA damage: .OH was detected in cells exposed to H2O2; the DNA base, deoxyguanosine, was hydroxylated in cells exposed to H2O2; and intracellular iron was essential for induction of DNA strand breaks. PMID:2843565

HER2-specific T cells target primary glioblastoma stem cells and induce regression of autologous experimental tumors.

PubMed

Ahmed, Nabil; Salsman, Vita S; Kew, Yvonne; Shaffer, Donald; Powell, Suzanne; Zhang, Yi J; Grossman, Robert G; Heslop, Helen E; Gottschalk, Stephen

2010-01-15

Glioblastoma multiforme (GBM) is the most aggressive human primary brain tumor and is currently incurable. Immunotherapies have the potential to target GBM stem cells, which are resistant to conventional therapies. Human epidermal growth factor receptor 2 (HER2) is a validated immunotherapy target, and we determined if HER2-specific T cells can be generated from GBM patients that will target autologous HER2-positive GBMs and their CD133-positive stem cell compartment. HER2-specific T cells from 10 consecutive GBM patients were generated by transduction with a retroviral vector encoding a HER2-specific chimeric antigen receptor. The effector function of HER2-specific T cells against autologous GBM cells, including CD133-positive stem cells, was evaluated in vitro and in an orthotopic murine xenograft model. Stimulation of HER2-specific T cells with HER2-positive autologous GBM cells resulted in T-cell proliferation and secretion of IFN-gamma and interleukin-2 in a HER2-dependent manner. Patients' HER2-specific T cells killed CD133-positive and CD133-negative cells derived from primary HER2-positive GBMs, whereas HER2-negative tumor cells were not killed. Injection of HER2-specific T cells induced sustained regression of autologous GBM xenografts established in the brain of severe combined immunodeficient mice. Gene transfer allows the reliable generation of HER2-specific T cells from GBM patients, which have potent antitumor activity against autologous HER2-positive tumors including their putative stem cells. Hence, the adoptive transfer of HER2-redirected T cells may be a promising immunotherapeutic approach for GBM.

Folate receptor‐targeted aminoglycoside‐derived polymers for transgene expression in cancer cells

PubMed Central

Godeshala, Sudhakar; Nitiyanandan, Rajeshwar; Thompson, Brian; Goklany, Sheba; Nielsen, David R.

2016-01-01

Abstract Targeted delivery of anticancer therapeutics can potentially overcome the limitations associated with current chemotherapeutic regimens. Folate receptors are overexpressed in several cancers, including ovarian, triple‐negative breast and bladder cancers, making them attractive for targeted delivery of nucleic acid therapeutics to these tumors. This work describes the synthesis, characterization and evaluation of folic acid‐conjugated, aminoglycoside‐derived polymers for targeted delivery of transgenes to breast and bladder cancer cell lines. Transgene expression was significantly higher with FA‐conjugated aminoglycoside‐derived polymers than with Lipofectamine, and these polymers demonstrated minimal cytotoxicty. Competitive inhibition using free folic acid significantly reduced transgene expression efficacy of folate‐targeted polymers, suggesting a role for folate receptor‐mediated uptake. High efficacy FA‐targeted polymers were employed to deliver a plasmid expressing the TRAIL protein, which induced death in cancer cells. These results indicate that FA‐conjugated aminoglycoside‐derived polymers are promising for targeted delivery of nucleic acids to cancer cells that overexpress folate receptors. PMID:29313013

A network of heterochronic genes including Imp1 regulates temporal changes in stem cell properties

PubMed Central

Nishino, Jinsuke; Kim, Sunjung; Zhu, Yuan; Zhu, Hao; Morrison, Sean J

2013-01-01

Stem cell properties change over time to match the changing growth and regeneration demands of tissues. We showed previously that adult forebrain stem cell function declines during aging because of increased expression of let-7 microRNAs, evolutionarily conserved heterochronic genes that reduce HMGA2 expression. Here we asked whether let-7 targets also regulate changes between fetal and adult stem cells. We found a second let-7 target, the RNA binding protein IMP1, that is expressed by fetal, but not adult, neural stem cells. IMP1 expression was promoted by Wnt signaling and Lin28a expression and opposed by let-7 microRNAs. Imp1-deficient neural stem cells were prematurely depleted in the dorsal telencephalon due to accelerated differentiation, impairing pallial expansion. IMP1 post-transcriptionally inhibited the expression of differentiation-associated genes while promoting the expression of self-renewal genes, including Hmga2. A network of heterochronic gene products including Lin28a, let-7, IMP1, and HMGA2 thus regulates temporal changes in stem cell properties. DOI: http://dx.doi.org/10.7554/eLife.00924.001 PMID:24192035

Shared target antigens on cancer cells and tissue stem cells: go or no-go for CAR T cells?

PubMed

Hombach, Andreas A; Abken, Hinrich

2017-02-01

Adoptive therapy with chimeric antigen receptor (CAR) T cells redirected towards CD19 produces remissions of B cell malignancies, however, it also eradicates healthy B cells sharing the target antigen. Such 'on-target off-tumor' toxicity raises serious safety concerns when the target antigen is also expressed by tissue stem cells, with the risk of lasting tissue destruction. Areas covered: We discuss CAR T cell targeting of activation antigens versus lineage associated antigens on the basis of recent experimental and animal data and the literature in the field. Expert commentary: Targeting an activation associated antigen which is transiently expressed by stem cells seems to be safe, like CAR T cells targeting CD30 spare CD30 + hematopoietic stem and progenitor cells while eliminating CD30 + lymphoma cells, whereas targeting lineage associated antigens which increase in expression during cell maturation, like folate receptor-β and CD123, is of risk to destruct tissue stem cells.

Specific elimination of CD133+ tumor cells with targeted oncolytic measles virus.

PubMed

Bach, Patricia; Abel, Tobias; Hoffmann, Christopher; Gal, Zoltan; Braun, Gundula; Voelker, Iris; Ball, Claudia R; Johnston, Ian C D; Lauer, Ulrich M; Herold-Mende, Christel; Mühlebach, Michael D; Glimm, Hanno; Buchholz, Christian J

2013-01-15

Tumor-initiating cells (TIC) are critical yet evasive targets for the development of more effective antitumoral strategies. The cell surface marker CD133 is frequently used to identify TICs of various tumor entities, including hepatocellular cancer and glioblastoma. Here, we describe oncolytic measles viruses (MV) retargeted to CD133. The viruses, termed MV-141.7 and MV-AC133, infected and selectively lysed CD133(+) tumor cells. Both viruses exerted strong antitumoral effects on human hepatocellular carcinoma growing subcutaneously or multifocally in the peritoneal cavity of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Notably, the CD133-targeted viruses were more effective in prolonging survival than the parental MV-NSe, which is currently assessed as oncolytic agent in clinical trials. Interestingly, target receptor overexpression or increased spreading kinetics through tumor cells were excluded as being causative for the enhanced oncolytic activity of CD133-targeted viruses. MV-141.7 was also effective in mouse models of orthotopic glioma tumor spheres and primary colon cancer. Our results indicate that CD133-targeted measles viruses selectively eliminate CD133(+) cells from tumor tissue, offering a key tool for research in tumor biology and cancer therapy.

Cytotoxic T cells use mechanical force to potentiate target cell killing

PubMed Central

Basu, Roshni; Whitlock, Benjamin M.; Husson, Julien; Le Floc’h, Audrey; Jin, Weiyang; Oyler-Yaniv, Alon; Dotiwala, Farokh; Giannone, Gregory; Hivroz, Claire; Biais, Nicolas; Lieberman, Judy; Kam, Lance C.; Huse, Morgan

2016-01-01

SUMMARY The immunological synapse formed between a cytotoxic T lymphocyte (CTL) and an infected or transformed target cell is a physically active structure capable of exerting mechanical force. Here, we investigated whether synaptic forces promote the destruction of target cells. CTLs kill by secreting toxic proteases and the pore forming protein perforin into the synapse. Biophysical experiments revealed a striking correlation between the magnitude of force exertion across the synapse and the speed of perforin pore formation on the target cell, implying that force potentiates cytotoxicity by enhancing perforin activity. Consistent with this interpretation, we found that increasing target cell tension augmented pore formation by perforin and killing by CTLs. Our data also indicate that CTLs coordinate perforin release and force exertion in space and time. These results reveal an unappreciated physical dimension to lymphocyte function and demonstrate that cells use mechanical forces to control the activity of outgoing chemical signals. PMID:26924577

Cytotoxic T Cells Use Mechanical Force to Potentiate Target Cell Killing.

PubMed

Basu, Roshni; Whitlock, Benjamin M; Husson, Julien; Le Floc'h, Audrey; Jin, Weiyang; Oyler-Yaniv, Alon; Dotiwala, Farokh; Giannone, Gregory; Hivroz, Claire; Biais, Nicolas; Lieberman, Judy; Kam, Lance C; Huse, Morgan

2016-03-24

The immunological synapse formed between a cytotoxic T lymphocyte (CTL) and an infected or transformed target cell is a physically active structure capable of exerting mechanical force. Here, we investigated whether synaptic forces promote the destruction of target cells. CTLs kill by secreting toxic proteases and the pore forming protein perforin into the synapse. Biophysical experiments revealed a striking correlation between the magnitude of force exertion across the synapse and the speed of perforin pore formation on the target cell, implying that force potentiates cytotoxicity by enhancing perforin activity. Consistent with this interpretation, we found that increasing target cell tension augmented pore formation by perforin and killing by CTLs. Our data also indicate that CTLs coordinate perforin release and force exertion in space and time. These results reveal an unappreciated physical dimension to lymphocyte function and demonstrate that cells use mechanical forces to control the activity of outgoing chemical signals. Copyright © 2016 Elsevier Inc. All rights reserved.

Cell-to-Cell Transmission Can Overcome Multiple Donor and Target Cell Barriers Imposed on Cell-Free HIV

PubMed Central

Ilinskaya, Anna; Dorjbal, Batsukh; Truong, Rosaline; Derse, David; Uchil, Pradeep D.; Heidecker, Gisela; Mothes, Walther

2013-01-01

Virus transmission can occur either by a cell-free mode through the extracellular space or by cell-to-cell transmission involving direct cell-to-cell contact. The factors that determine whether a virus spreads by either pathway are poorly understood. Here, we assessed the relative contribution of cell-free and cell-to-cell transmission to the spreading of the human immunodeficiency virus (HIV). We demonstrate that HIV can spread by a cell-free pathway if all the steps of the viral replication cycle are efficiently supported in highly permissive cells. However, when the cell-free path was systematically hindered at various steps, HIV transmission became contact-dependent. Cell-to-cell transmission overcame barriers introduced in the donor cell at the level of gene expression and surface retention by the restriction factor tetherin. Moreover, neutralizing antibodies that efficiently inhibit cell-free HIV were less effective against cell-to-cell transmitted virus. HIV cell-to-cell transmission also efficiently infected target T cells that were relatively poorly susceptible to cell-free HIV. Importantly, we demonstrate that the donor and target cell types influence critically the extent by which cell-to-cell transmission can overcome each barrier. Mechanistically, cell-to-cell transmission promoted HIV spread to more cells and infected target cells with a higher proviral content than observed for cell-free virus. Our data demonstrate that the frequently observed contact-dependent spread of HIV is the result of specific features in donor and target cell types, thus offering an explanation for conflicting reports on the extent of cell-to-cell transmission of HIV. PMID:23308151

Single-Cell Droplet Microfluidic Screening for Antibodies Specifically Binding to Target Cells.

PubMed

Shembekar, Nachiket; Hu, Hongxing; Eustace, David; Merten, Christoph A

2018-02-20

Monoclonal antibodies are a main player in modern drug discovery. Many antibody screening formats exist, each with specific advantages and limitations. Nonetheless, it remains challenging to screen antibodies for the binding of cell-surface receptors (the most important class of all drug targets) or for the binding to target cells rather than purified proteins. Here, we present a high-throughput droplet microfluidics approach employing dual-color normalized fluorescence readout to detect antibody binding. This enables us to obtain quantitative data on target cell recognition, using as little as 33 fg of IgG per assay. Starting with an excess of hybridoma cells releasing unspecific antibodies, individual clones secreting specific binders (of target cells co-encapsulated into droplets) could be enriched 220-fold after sorting 80,000 clones in a single experiment. This opens the way for therapeutic antibody discovery, especially since the single-cell approach is in principle also applicable to primary human plasma cells. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Targeting CD22 in B-cell malignancies: current status and clinical outlook.

PubMed

Sullivan-Chang, Loretta; O'Donnell, Robert T; Tuscano, Joseph M

2013-08-01

CD22 is a B-cell-specific transmembrane glycoprotein found on the surface of most B cells; it modulates B-cell function, survival and apoptosis. CD22 has emerged as an ideal target for monoclonal antibody (mAb)-based therapy of B-cell malignancies including most lymphomas and many leukemias. Epratuzumab, an anti-CD22 mAb, has been developed in various forms, including as an unlabeled (naked) mAb, as a radioimmunotherapeutic, as an antibody drug conjugate (ADC), and as a vehicle for CD22-targeted nanoparticles. While clinical trials with unlabeled epratuzumab have demonstrated modest results, its combination with rituximab in phase II studies has been more encouraging. Based on the potential for CD22 to become internalized, CD22-targeted constructs carrying radioisotopes or toxins have generated promising results. Radioimmunotherapy, utilizing ⁹⁰Y-labeled epratuzumab, was shown to be highly effective in patients with follicular lymphoma, generating a complete response (CR) rate of 92 % and progression-free survival of more than 2 years. ADC therapy is a promising therapeutic approach to B-cell malignancies which includes the direct conjugation of mAbs with cytotoxic agents. Phase II studies of inotuzumab ozogamicin, an ADC which combines anti-CD22 mAb with calicheamicin, an enediyne antibiotic which mediates apoptosis, in patients with acute lymphoblastic leukemia have produced an overall response rate (ORR) of greater than 50 % in treatment-refractory patients. Phase I trials of moxetumomab pasudotox, an ADC which combines anti-CD22 with PE38, a fragment of Pseudomonas exotoxin A, have been completed in hairy cell leukemia with a ORR of 86 %. Finally, a review of CD22-targeted nanoparticles, that include a doxorubicin-containing lipid complex that uses synthetic high-affinity CD22 ligand mimetics as well as anti-CD22 mAb-coated pegylated liposomas doxorubin (PLD), has demonstrated promising results in pre-clinical models of human lymphoma. Moreover, novel anti

Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in-situ targeting of dendritic cells.

PubMed

Morelli, Adrian E; Thomson, Angus W

2014-08-01

Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCregs) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCregs (donor or recipient) and their mode of action, in-situ targeting of DCregs, and optimal therapeutic regimens to promote DCreg function. Recent studies have defined protocols and mechanisms whereby ex-vivo-generated DCregs of donor or recipient origin subvert allogeneic T-cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen is acquired, processed and presented by autologous dendritic cells, on the stability of DCregs, and on in-situ targeting of dendritic cells to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCregs in a clinically relevant nonhuman primate organ transplant model and production of clinical grade DCregs support early evaluation of DCreg therapy in human graft recipients. We discuss strategies currently used to promote dendritic cell tolerogenicity, including DCreg therapy and in-situ targeting of dendritic cells, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application.

Target cell specific antibody-based photosensitizers for photodynamic therapy

NASA Astrophysics Data System (ADS)

Rosenblum, Lauren T.; Mitsunaga, Makoto; Kakareka, John W.; Morgan, Nicole Y.; Pohida, Thomas J.; Choyke, Peter L.; Kobayashi, Hisataka

2011-03-01

In photodynamic therapy (PDT), localized monochromatic light is used to activate targeted photosensitizers (PS) to induce cellular damage through the generation of cytotoxic species such as singlet oxygen. While first-generation PS passively targeted malignancies, a variety of targeting mechanisms have since been studied, including specifically activatable agents. Antibody internalization has previously been employed as a fluorescence activation system and could potentially enable similar activation of PS. TAMRA, Rhodamine-B and Rhodamine-6G were conjugated to trastuzumab (brand name Herceptin), a humanized monoclonal antibody with specificity for the human epidermal growth factor receptor 2 (HER2), to create quenched PS (Tra-TAM, Tra-RhoB, and Tra-Rho6G). Specific PDT with Tra-TAM and Tra-Rho6G, which formed covalently bound H-dimers, was demonstrated in HER2+ cells: Minimal cell death (<6%) was observed in all treatments of the HER2- cell line (BALB/3T3) and in treatments the HER2+ cell line (3T3/HER2) with light or trastuzumab only. There was significant light-induced cell death in HER2 expressing cells using Tra-TAM (3% dead without light, 20% at 50 J/cm2, 46% at 100 J/cm2) and Tra-Rho6G (5% dead without light, 22% at 50 J/cm2, 46% at 100 J/cm2). No efficacy was observed in treatment with Tra-RhoB, which was also non-specifically taken up by BALB/3T3 cells and which had weaker PS-antibody interactions (as demonstrated by visualization of protein and fluorescence on SDS-PAGE).

Controversies in targeted therapy of adult T cell leukemia/lymphoma: ON target or OFF target effects?

PubMed

Nasr, Rihab; El Hajj, Hiba; Kfoury, Youmna; de Thé, Hugues; Hermine, Olivier; Bazarbachi, Ali

2011-06-01

Adult T cell leukemia/lymphoma (ATL) represents an ideal model for targeted therapy because of intrinsic chemo-resistance of ATL cells and the presence of two well identified targets: the HTLV-I retrovirus and the viral oncoprotein Tax. The combination of zidovudine (AZT) and interferon-alpha (IFN) has a dramatic impact on survival of ATL patients. Although the mechanism of action remains unclear, arguments in favor or against a direct antiviral effect will be discussed. Yet, most patients relapse and alternative therapies are mandatory. IFN and arsenic trioxide induce Tax proteolysis, synergize to induce apoptosis in ATL cells and cure Tax-driven ATL in mice through specific targeting of leukemia initiating cell activity. These results provide a biological basis for the clinical success of arsenic/IFN/AZT therapy in ATL patients and suggest that both extinction of viral replication (AZT) and Tax degradation (arsenic/IFN) are needed to cure ATL.

Antibody-targeted interleukin 2 stimulates T-cell killing of autologous tumor cells.

PubMed Central

Gillies, S D; Reilly, E B; Lo, K M; Reisfeld, R A

1992-01-01

A genetically engineered fusion protein consisting of a chimeric anti-ganglioside GD2 antibody (ch14.18) and interleukin 2 (IL2) was tested for its ability to enhance the killing of autologous GD2-expressing melanoma target cells by a tumor-infiltrating lymphocyte line (660 TIL). The fusion of IL2 to the carboxyl terminus of the immunoglobulin heavy chain did not reduce IL2 activity as measured in a standard proliferation assay using either mouse or human T-cell lines. Antigen-binding activity was greater than that of the native chimeric antibody. The ability of resting 660 TIL cells to kill their autologous GD2-positive target cells was enhanced if the target cells were first coated with the fusion protein. This stimulation of killing was greater than that of uncoated cells in the presence of equivalent or higher concentrations of free IL2. Such antibody-cytokine fusion proteins may prove useful in targeting the biological effect of IL2 and other cytokines to tumor cells and in this way stimulate their immune destruction. Images PMID:1741398

[Current strategies in the treatment of renal-cell cancer: targeted therapies].

PubMed

Trigo, José Manuel; Bellmunt, Joaquim

2008-03-22

Renal-cell carcinoma represents 95% of all renal tumours. The Von Hippel-Lindau (VHL) tumor-suppressor gene is mutated or silenced in most clear cell renal carcinomas. pVHL loss results in the stabilization of the heterodimeric transcription factor hypoxia-inducible factor (HIF) and enhanced transactivation of HIF target genes. HIF itself has been difficult to inhibit with drug-like molecules although a number of agents that indirectly inhibit HIF, including mTOR (mammalian target of rapamycin) inhibitors, have been identified. Moreover, a number of drugs have been developed that target HIF-responsive gene products, such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), implicated in tumor angiogenesis. Many of these targeted therapies, especially sunitinib, have demonstrated significant activity in kidney cancer clinical trials and represent a substantive advance in the treatment of this disease.

Cell-targeted platinum nanoparticles and nanoparticle clusters.

PubMed

Papst, Stefanie; Brimble, Margaret A; Evans, Clive W; Verdon, Daniel J; Feisst, Vaughan; Dunbar, P Rod; Tilley, Richard D; Williams, David E

2015-06-21

Herein, we report the facile preparation of cell-targeted platinum nanoparticles (PtNPs), through the design of peptides that, as a single molecule added in small concentration during the synthesis, control the size of PtNP clusters during their growth, stabilise the PtNPs in aqueous suspension and enable the functionalisation of the PtNPs with a versatile range of cell-targeting ligands. Water-soluble PtNPs targeted respectively at blood group antigens and at integrin receptors are demonstrated.

Combined targeting of lentiviral vectors and positioning of transduced cells by magnetic nanoparticles

PubMed Central

Hofmann, Andreas; Wenzel, Daniela; Becher, Ulrich M.; Freitag, Daniel F.; Klein, Alexandra M.; Eberbeck, Dietmar; Schulte, Maike; Zimmermann, Katrin; Bergemann, Christian; Gleich, Bernhard; Roell, Wilhelm; Weyh, Thomas; Trahms, Lutz; Nickenig, Georg; Fleischmann, Bernd K.; Pfeifer, Alexander

2009-01-01

Targeting of viral vectors is a major challenge for in vivo gene delivery, especially after intravascular application. In addition, targeting of the endothelium itself would be of importance for gene-based therapies of vascular disease. Here, we used magnetic nanoparticles (MNPs) to combine cell transduction and positioning in the vascular system under clinically relevant, nonpermissive conditions, including hydrodynamic forces and hypothermia. The use of MNPs enhanced transduction efficiency of endothelial cells and enabled direct endothelial targeting of lentiviral vectors (LVs) by magnetic force, even in perfused vessels. In addition, application of external magnetic fields to mice significantly changed LV/MNP biodistribution in vivo. LV/MNP-transduced cells exhibited superparamagnetic behavior as measured by magnetorelaxometry, and they were efficiently retained by magnetic fields. The magnetic interactions were strong enough to position MNP-containing endothelial cells at the intima of vessels under physiological flow conditions. Importantly, magnetic positioning of MNP-labeled cells was also achieved in vivo in an injury model of the mouse carotid artery. Intravascular gene targeting can be combined with positioning of the transduced cells via nanomagnetic particles, thereby combining gene- and cell-based therapies. PMID:19118196

Combined targeting of lentiviral vectors and positioning of transduced cells by magnetic nanoparticles.

PubMed

Hofmann, Andreas; Wenzel, Daniela; Becher, Ulrich M; Freitag, Daniel F; Klein, Alexandra M; Eberbeck, Dietmar; Schulte, Maike; Zimmermann, Katrin; Bergemann, Christian; Gleich, Bernhard; Roell, Wilhelm; Weyh, Thomas; Trahms, Lutz; Nickenig, Georg; Fleischmann, Bernd K; Pfeifer, Alexander

2009-01-06

Targeting of viral vectors is a major challenge for in vivo gene delivery, especially after intravascular application. In addition, targeting of the endothelium itself would be of importance for gene-based therapies of vascular disease. Here, we used magnetic nanoparticles (MNPs) to combine cell transduction and positioning in the vascular system under clinically relevant, nonpermissive conditions, including hydrodynamic forces and hypothermia. The use of MNPs enhanced transduction efficiency of endothelial cells and enabled direct endothelial targeting of lentiviral vectors (LVs) by magnetic force, even in perfused vessels. In addition, application of external magnetic fields to mice significantly changed LV/MNP biodistribution in vivo. LV/MNP-transduced cells exhibited superparamagnetic behavior as measured by magnetorelaxometry, and they were efficiently retained by magnetic fields. The magnetic interactions were strong enough to position MNP-containing endothelial cells at the intima of vessels under physiological flow conditions. Importantly, magnetic positioning of MNP-labeled cells was also achieved in vivo in an injury model of the mouse carotid artery. Intravascular gene targeting can be combined with positioning of the transduced cells via nanomagnetic particles, thereby combining gene- and cell-based therapies.

Controversies in Targeted Therapy of Adult T Cell Leukemia/Lymphoma: ON Target or OFF Target Effects?

PubMed Central

Nasr, Rihab; Hajj, Hiba El; Kfoury, Youmna; de Thé, Hugues; Hermine, Olivier; Bazarbachi, Ali

2011-01-01

Adult T cell leukemia/lymphoma (ATL) represents an ideal model for targeted therapy because of intrinsic chemo-resistance of ATL cells and the presence of two well identified targets: the HTLV-I retrovirus and the viral oncoprotein Tax. The combination of zidovudine (AZT) and interferon-alpha (IFN) has a dramatic impact on survival of ATL patients. Although the mechanism of action remains unclear, arguments in favor or against a direct antiviral effect will be discussed. Yet, most patients relapse and alternative therapies are mandatory. IFN and arsenic trioxide induce Tax proteolysis, synergize to induce apoptosis in ATL cells and cure Tax-driven ATL in mice through specific targeting of leukemia initiating cell activity. These results provide a biological basis for the clinical success of arsenic/IFN/AZT therapy in ATL patients and suggest that both extinction of viral replication (AZT) and Tax degradation (arsenic/IFN) are needed to cure ATL. PMID:21994752

Targeted deletion of RANKL in M cell inducer cells by the Col6a1-Cre driver.

PubMed

Nagashima, Kazuki; Sawa, Shinichiro; Nitta, Takeshi; Prados, Alejandro; Koliaraki, Vasiliki; Kollias, George; Nakashima, Tomoki; Takayanagi, Hiroshi

2017-11-04

The gut-associated lymphoid tissues (GALTs), including Peyer's patches (PPs), cryptopatches (CPs) and isolated lymphoid follicles (ILFs), establish a host-microbe symbiosis by the promotion of immune reactions against gut microbes. Microfold cell inducer (MCi) cells in GALTs are the recently identified mesenchymal cells that express the cytokine RANKL and initiate bacteria-specific immunoglobulin A (IgA) production via induction of microfold (M) cell differentiation. In the previous study, the Twist2-Cre driver was utilized for gene deletion in mesenchymal cells including MCi cells. In order to investigate MCi cells more extensively, it will be necessary to develop experimental tools in addition to the Twist2-Cre driver mice and characterize such drivers in specificity and efficiency. Here we show that M cell differentiation and IgA production are impaired in the targeted deletion of RANKL by the Col6a1-Cre driver. We compared Col6a1-Cre with Twist2-Cre in terms of the specificity for mesenchymal cells in GALTs. Col6a1-Cre CAG-CAT-EGFP mice exhibited EGFP expression in podoplanin + CD31 - cells including MCi cells, while Twist2-Cre mice were shown to target endothelial cells and podoplanin + CD31 - cells. Tnfsf11 fl/Δ Col6a1-Cre mice exhibited the absence of M cells and severe IgA reduction together with an alteration in gut microbial composition. Moreover, we analyzed germ free mice to test whether changes in the microbiota are the cause of M cell deficiency. M cell differentiation was normal in the CPs/ILFs of germ free mice, indicating that MCi cells induce M cells independently of microbial colonization. This study demonstrates that Col6a1-Cre driver mice are as useful as Twist2-Cre driver mice for functional analyses of GALT-resident mesenchymal cells, including MCi cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Targeting Gas6/TAM in cancer cells and tumor microenvironment.

PubMed

Wu, Guiling; Ma, Zhiqiang; Cheng, Yicheng; Hu, Wei; Deng, Chao; Jiang, Shuai; Li, Tian; Chen, Fulin; Yang, Yang

2018-01-31

Growth arrest-specific 6, also known as Gas6, is a human gene encoding the Gas6 protein, which was originally found to be upregulated in growth-arrested fibroblasts. Gas6 is a member of the vitamin K-dependent family of proteins expressed in many human tissues and regulates several biological processes in cells, including proliferation, survival and migration, by binding to its receptors Tyro3, Axl and Mer (TAM). In recent years, the roles of Gas6/TAM signalling in cancer cells and the tumour microenvironment have been studied, and some progress has made in targeted therapy, providing new potential directions for future investigations of cancer treatment. In this review, we introduce the Gas6 and TAM receptors and describe their involvement in different cancers and discuss the roles of Gas6 in cancer cells, the tumour microenvironment and metastasis. Finally, we introduce recent studies on Gas6/TAM targeting in cancer therapy, which will assist in the experimental design of future analyses and increase the potential use of Gas6 as a therapeutic target for cancer.

CD22-targeted CAR T cells induce remission in B-ALL that is naive or resistant to CD19-targeted CAR immunotherapy.

PubMed

Fry, Terry J; Shah, Nirali N; Orentas, Rimas J; Stetler-Stevenson, Maryalice; Yuan, Constance M; Ramakrishna, Sneha; Wolters, Pamela; Martin, Staci; Delbrook, Cindy; Yates, Bonnie; Shalabi, Haneen; Fountaine, Thomas J; Shern, Jack F; Majzner, Robbie G; Stroncek, David F; Sabatino, Marianna; Feng, Yang; Dimitrov, Dimiter S; Zhang, Ling; Nguyen, Sang; Qin, Haiying; Dropulic, Boro; Lee, Daniel W; Mackall, Crystal L

2018-01-01

Chimeric antigen receptor (CAR) T cells targeting CD19 mediate potent effects in relapsed and/or refractory pre-B cell acute lymphoblastic leukemia (B-ALL), but antigen loss is a frequent cause of resistance to CD19-targeted immunotherapy. CD22 is also expressed in most cases of B-ALL and is usually retained following CD19 loss. We report results from a phase 1 trial testing a new CD22-targeted CAR (CD22-CAR) in 21 children and adults, including 17 who were previously treated with CD19-directed immunotherapy. Dose-dependent antileukemic activity was observed, with complete remission obtained in 73% (11/15) of patients receiving ≥1 × 10 6 CD22-CAR T cells per kg body weight, including 5 of 5 patients with CD19 dim or CD19 - B-ALL. Median remission duration was 6 months. Relapses were associated with diminished CD22 site density that likely permitted CD22 + cell escape from killing by CD22-CAR T cells. These results are the first to establish the clinical activity of a CD22-CAR in B-ALL, including leukemia resistant to anti-CD19 immunotherapy, demonstrating potency against B-ALL comparable to that of CD19-CAR at biologically active doses. Our results also highlight the critical role played by antigen density in regulating CAR function.

Target-cancer-cell-specific activatable fluorescence imaging probes: rational design and in vivo applications.

PubMed

Kobayashi, Hisataka; Choyke, Peter L

2011-02-15

Conventional imaging methods, such as angiography, computed tomography (CT), magnetic resonance imaging (MRI), and radionuclide imaging, rely on contrast agents (iodine, gadolinium, and radioisotopes, for example) that are "always on." Although these indicators have proven clinically useful, their sensitivity is lacking because of inadequate target-to-background signal ratio. A unique aspect of optical imaging is that fluorescence probes can be designed to be activatable, that is, only "turned on" under certain conditions. These probes are engineered to emit signal only after binding a target tissue; this design greatly increases sensitivity and specificity in the detection of disease. Current research focuses on two basic types of activatable fluorescence probes. The first developed were conventional enzymatically activatable probes. These fluorescent molecules exist in the quenched state until activated by enzymatic cleavage, which occurs mostly outside of the cells. However, more recently, researchers have begun designing target-cell-specific activatable probes. These fluorophores exist in the quenched state until activated within targeted cells by endolysosomal processing, which results when the probe binds specific receptors on the cell surface and is subsequently internalized. In this Account, we present a review of the rational design and in vivo applications of target-cell-specific activatable probes. In engineering these probes, researchers have asserted control over a variety of factors, including photochemistry, pharmacological profile, and biological properties. Their progress has recently allowed the rational design and synthesis of target-cell-specific activatable fluorescence imaging probes, which can be conjugated to a wide variety of targeting molecules. Several different photochemical mechanisms have been utilized, each of which offers a unique capability for probe design. These include self-quenching, homo- and hetero-fluorescence resonance

Slp-76 is a critical determinant of NK-cell mediated recognition of missing-self targets.

PubMed

Lampe, Kristin; Endale, Mehari; Cashman, Siobhan; Fang, Hao; Mattner, Jochen; Hildeman, David; Hoebe, Kasper

2015-07-01

Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying "missing-self" recognition, including the involvement of activating receptors, remain poorly understood. Using ethyl-N-nitrosourea mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell mediated recognition and elimination of "missing-self" targets. The causative mutation was linked to chromosome 11 and identified as a missense mutation (Thr428Ile) in the SH2 domain of Slp-76-a critical adapter molecule downstream of ITAM-containing surface receptors. The Slp-76 Ace mutation behaved as a hypomorphic allele-while no major defects were observed in conventional T-cell development/function, a marked defect in NK cell mediated elimination of β2-microglobulin (β2M) deficient target cells was observed. Further studies revealed Slp-76 to control NK-cell receptor expression and maturation; however, activation of Slp-76(ace/ace) NK cells through ITAM-containing NK-cell receptors or allogeneic/tumor target cells appeared largely unaffected. Imagestream analysis of the NK-β2M(-/-) target cell synapse revealed a specific defect in actin recruitment to the conjugate synapse in Slp-76(ace/ace) NK cells. Overall these studies establish Slp-76 as a critical determinant of NK-cell development and NK cell mediated elimination of missing-self target cells in mice. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Slp-76 is a critical determinant of NK cell-mediated recognition of missing-self targets

PubMed Central

Lampe, Kristin; Endale, Mehari; Cashman, Siobhan; Fang, Hao; Mattner, Jochen; Hildeman, David; Hoebe, Kasper

2015-01-01

Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying “missing-self” recognition, including the involvement of activating receptors, remain poorly understood. Using ENU mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell-mediated recognition and elimination of “missing-self” targets. The causative mutation was linked to chromosome 11 and identified as a missense mutation [Thr428Ile] in the SH2 domain of Slp-76—a critical adapter molecule downstream of ITAM-containing surface receptors. The Slp-76 Ace mutation behaved as a hypomorphic allele—while no major defects were observed in conventional T cell development/function, a marked defect in NK cell-mediated elimination of β2-Microglobulin (β2M)-deficient target cells was observed. Further studies revealed Slp-76 to control NK cell receptor expression and maturation, however, activation of Slp-76ace/ace NK cells through ITAM-containing NK cell receptors or allogeneic/tumor target cells appeared largely unaffected. Imagestream analysis of the NK-β2M−/− target cell synapse, revealed a specific defect in actin recruitment to the conjugate synapse in Slp-76ace/ace NK cells. Overall these studies establish Slp-76 as a critical determinant of NK cell development and NK cell-mediated elimination of missing-self target cells. PMID:25929249

Surface Proteins of Gram-Positive Bacteria and Mechanisms of Their Targeting to the Cell Wall Envelope

PubMed Central

Navarre, William Wiley; Schneewind, Olaf

1999-01-01

The cell wall envelope of gram-positive bacteria is a macromolecular, exoskeletal organelle that is assembled and turned over at designated sites. The cell wall also functions as a surface organelle that allows gram-positive pathogens to interact with their environment, in particular the tissues of the infected host. All of these functions require that surface proteins and enzymes be properly targeted to the cell wall envelope. Two basic mechanisms, cell wall sorting and targeting, have been identified. Cell well sorting is the covalent attachment of surface proteins to the peptidoglycan via a C-terminal sorting signal that contains a consensus LPXTG sequence. More than 100 proteins that possess cell wall-sorting signals, including the M proteins of Streptococcus pyogenes, protein A of Staphylococcus aureus, and several internalins of Listeria monocytogenes, have been identified. Cell wall targeting involves the noncovalent attachment of proteins to the cell surface via specialized binding domains. Several of these wall-binding domains appear to interact with secondary wall polymers that are associated with the peptidoglycan, for example teichoic acids and polysaccharides. Proteins that are targeted to the cell surface include muralytic enzymes such as autolysins, lysostaphin, and phage lytic enzymes. Other examples for targeted proteins are the surface S-layer proteins of bacilli and clostridia, as well as virulence factors required for the pathogenesis of L. monocytogenes (internalin B) and Streptococcus pneumoniae (PspA) infections. In this review we describe the mechanisms for both sorting and targeting of proteins to the envelope of gram-positive bacteria and review the functions of known surface proteins. PMID:10066836

Cell-permeable nanobodies for targeted immunolabelling and antigen manipulation in living cells

NASA Astrophysics Data System (ADS)

Herce, Henry D.; Schumacher, Dominik; Schneider, Anselm F. L.; Ludwig, Anne K.; Mann, Florian A.; Fillies, Marion; Kasper, Marc-André; Reinke, Stefan; Krause, Eberhard; Leonhardt, Heinrich; Cardoso, M. Cristina; Hackenberger, Christian P. R.

2017-08-01

Functional antibody delivery in living cells would enable the labelling and manipulation of intracellular antigens, which constitutes a long-thought goal in cell biology and medicine. Here we present a modular strategy to create functional cell-permeable nanobodies capable of targeted labelling and manipulation of intracellular antigens in living cells. The cell-permeable nanobodies are formed by the site-specific attachment of intracellularly stable (or cleavable) cyclic arginine-rich cell-penetrating peptides to camelid-derived single-chain VHH antibody fragments. We used this strategy for the non-endocytic delivery of two recombinant nanobodies into living cells, which enabled the relocalization of the polymerase clamp PCNA (proliferating cell nuclear antigen) and tumour suppressor p53 to the nucleolus, and thereby allowed the detection of protein-protein interactions that involve these two proteins in living cells. Furthermore, cell-permeable nanobodies permitted the co-transport of therapeutically relevant proteins, such as Mecp2, into the cells. This technology constitutes a major step in the labelling, delivery and targeted manipulation of intracellular antigens. Ultimately, this approach opens the door towards immunostaining in living cells and the expansion of immunotherapies to intracellular antigen targets.

Targeting of follicle stimulating hormone peptide-conjugated dendrimers to ovarian cancer cells

NASA Astrophysics Data System (ADS)

Modi, Dimple A.; Sunoqrot, Suhair; Bugno, Jason; Lantvit, Daniel D.; Hong, Seungpyo; Burdette, Joanna E.

2014-02-01

Ovarian cancer is the most lethal gynecological malignancy. Current treatment modalities include a combination of surgery and chemotherapy, which often lead to loss of fertility in premenopausal women and a myriad of systemic side effects. To address these issues, we have designed poly(amidoamine) (PAMAM) dendrimers to selectively target the follicle stimulating hormone receptor (FSHR), which is overexpressed by tumorigenic ovarian cancer cells but not by immature primordial follicles and other non-tumorigenic cells. Fluorescein-labeled generation 5 (G5) PAMAM dendrimers were conjugated with the binding peptide domain of FSH (FSH33) that has a high affinity to FSHR. The targeted dendrimers exhibited high receptor selectivity to FSHR-expressing OVCAR-3 cells, resulting in significant uptake and downregulation of an anti-apoptotic protein survivin, while showing minimal interactions with SKOV-3 cells that do not express FSHR. The selectivity of the FSH33-targeted dendrimers was further validated in 3D organ cultures of normal mouse ovaries. Immunostaining of the conjugates revealed their selective binding and uptake by ovarian surface epithelium (OSE) cells that express FSHR, while sparing the immature primordial follicles. In addition, an in vivo study monitoring tissue accumulation following a single intraperitoneal (i.p.) injection of the conjugates showed significantly higher accumulation of FSH33-targeted dendrimers in the ovary and oviduct compared to the non-targeted conjugates. These proof-of-concept findings highlight the potential of these FSH33-targeted dendrimers to serve as a delivery platform for anti-ovarian cancer drugs, while reducing their systemic side effects by preventing nonspecific uptake by the primordial follicles.Ovarian cancer is the most lethal gynecological malignancy. Current treatment modalities include a combination of surgery and chemotherapy, which often lead to loss of fertility in premenopausal women and a myriad of systemic side

The cell's nucleolus: an emerging target for chemotherapeutic intervention.

PubMed

Pickard, Amanda J; Bierbach, Ulrich

2013-09-01

The transient nucleolus plays a central role in the up-regulated synthesis of ribosomal RNA (rRNA) to sustain ribosome biogenesis, a hallmark of aberrant cell growth. This function, in conjunction with its unique pathohistological features in malignant cells and its ability to mediate apoptosis, renders this sub-nuclear structure a potential target for chemotherapeutic agents. In this Minireview, structurally and functionally diverse small molecules are discussed that have been reported to either interact with the nucleolus directly or perturb its function indirectly by acting on its dynamic components. These molecules include all major classes of nucleic-acid-targeted agents, antimetabolites, kinase inhibitors, anti-inflammatory drugs, natural product antibiotics, oligopeptides, as well as nanoparticles. Together, these molecules are invaluable probes of structure and function of the nucleolus. They also provide a unique opportunity to develop novel strategies for more selective and therefore better-tolerated chemotherapeutic intervention. In this regard, inhibition of RNA polymerase-I-mediated rRNA synthesis appears to be a promising mechanism for killing cancer cells. The recent development of molecules targeted at G-quadruplex-forming rRNA gene sequences, which are currently undergoing clinical trials, seems to attest to the success of this approach. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In situ Proteomic Profiling of Curcumin Targets in HCT116 Colon Cancer Cell Line.

PubMed

Wang, Jigang; Zhang, Jianbin; Zhang, Chong-Jing; Wong, Yin Kwan; Lim, Teck Kwang; Hua, Zi-Chun; Liu, Bin; Tannenbaum, Steven R; Shen, Han-Ming; Lin, Qingsong

2016-02-26

To date, the exact targets and mechanism of action of curcumin, a natural product with anti-inflammatory and anti-cancer properties, remain elusive. Here we synthesized a cell permeable curcumin probe (Cur-P) with an alkyne moiety, which can be tagged with biotin for affinity enrichment, or with a fluorescent dye for visualization of the direct-binding protein targets of curcumin in situ. iTRAQ(TM) quantitative proteomics approach was applied to distinguish the specific binding targets from the non-specific ones. In total, 197 proteins were confidently identified as curcumin binding targets from HCT116 colon cancer cell line. Gene Ontology analysis showed that the targets are broadly distributed and enriched in the nucleus, mitochondria and plasma membrane, and they are involved in various biological functions including metabolic process, regulation, response to stimulus and cellular process. Ingenuity Pathway Analysis(TM) (IPA) suggested that curcumin may exert its anticancer effects over multiple critical biological pathways including the EIF2, eIF4/p70S6K, mTOR signaling and mitochondrial dysfunction pathways. Functional validations confirmed that curcumin downregulates cellular protein synthesis, and induces autophagy, lysosomal activation and increased ROS production, thus leading to cell death.

In situ Proteomic Profiling of Curcumin Targets in HCT116 Colon Cancer Cell Line

PubMed Central

Wang, Jigang; Zhang, Jianbin; Zhang, Chong-Jing; Wong, Yin Kwan; Lim, Teck Kwang; Hua, Zi-Chun; Liu, Bin; Tannenbaum, Steven R.; Shen, Han-Ming; Lin, Qingsong

2016-01-01

To date, the exact targets and mechanism of action of curcumin, a natural product with anti-inflammatory and anti-cancer properties, remain elusive. Here we synthesized a cell permeable curcumin probe (Cur-P) with an alkyne moiety, which can be tagged with biotin for affinity enrichment, or with a fluorescent dye for visualization of the direct-binding protein targets of curcumin in situ. iTRAQTM quantitative proteomics approach was applied to distinguish the specific binding targets from the non-specific ones. In total, 197 proteins were confidently identified as curcumin binding targets from HCT116 colon cancer cell line. Gene Ontology analysis showed that the targets are broadly distributed and enriched in the nucleus, mitochondria and plasma membrane, and they are involved in various biological functions including metabolic process, regulation, response to stimulus and cellular process. Ingenuity Pathway AnalysisTM (IPA) suggested that curcumin may exert its anticancer effects over multiple critical biological pathways including the EIF2, eIF4/p70S6K, mTOR signaling and mitochondrial dysfunction pathways. Functional validations confirmed that curcumin downregulates cellular protein synthesis, and induces autophagy, lysosomal activation and increased ROS production, thus leading to cell death. PMID:26915414

Induction of viral interference by IPNV-carrier cells on target cells: A cell co-culture study.

PubMed

Parreño, Ricardo; Torres, Susana; Almagro, Lucía; Belló-Pérez, Melissa; Estepa, Amparo; Perez, Luis

2016-11-01

IPNV is a salmonid birnavirus that possesses the ability to establish asymptomatic persistent infections in a number of valuable fish species. The presence of IPNV may interfere with subsequent infection by other viruses. In the present study we show that an IPNV-carrier cell line (EPC IPNV ) can induce an antiviral state in fresh EPC by co-cultivating both cell types in three different ways: a "droplet" culture system, a plastic chamber setup, and a transmembrane (Transwell ® ) system. All three cell co-culture methods were proven useful to study donor/target cell interaction. Naïve EPC cells grown in contact with EPC IPNV cells develop resistance to VHSV superinfection. The transmembrane system seems best suited to examine gene expression in donor and target cells separately. Our findings point to the conclusion that one or more soluble factors produced by the IPNV carrier culture induce the innate immune response within the target cells. This antiviral response is associated to the up-regulation of interferon (ifn) and mx gene expression in target EPC cells. To our knowledge this is the first article describing co-culture systems to study the interplay between virus-carrier cells and naive cells in fish. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Generation of Functional Human Retinal Ganglion Cells with Target Specificity from Pluripotent Stem Cells by Chemically Defined Recapitulation of Developmental Mechanism.

PubMed

Teotia, Pooja; Chopra, Divyan A; Dravid, Shashank Manohar; Van Hook, Matthew J; Qiu, Fang; Morrison, John; Rizzino, Angie; Ahmad, Iqbal

2017-03-01

Glaucoma is a complex group of diseases wherein a selective degeneration of retinal ganglion cells (RGCs) lead to irreversible loss of vision. A comprehensive approach to glaucomatous RGC degeneration may include stem cells to functionally replace dead neurons through transplantation and understand RGCs vulnerability using a disease in a dish stem cell model. Both approaches require the directed generation of stable, functional, and target-specific RGCs from renewable sources of cells, that is, the embryonic stem cells and induced pluripotent stem cells. Here, we demonstrate a rapid and safe, stage-specific, chemically defined protocol that selectively generates RGCs across species, including human, by recapitulating the developmental mechanism. The de novo generated RGCs from pluripotent cells are similar to native RGCs at the molecular, biochemical, functional levels. They also express axon guidance molecules, and discriminate between specific and nonspecific targets, and are nontumorigenic. Stem Cells 2017;35:572-585. © 2016 AlphaMed Press.

Selection of Phage Display Peptides Targeting Human Pluripotent Stem Cell-Derived Progenitor Cell Lines.

PubMed

Bignone, Paola A; Krupa, Rachel A; West, Michael D; Larocca, David

2016-01-01

The ability of human pluripotent stem cells (hPS) to both self-renew and differentiate into virtually any cell type makes them a promising source of cells for cell-based regenerative therapies. However, stem cell identity, purity, and scalability remain formidable challenges that need to be overcome for translation of pluripotent stem cell research into clinical applications. Directed differentiation from hPS cells is inefficient and residual contamination with pluripotent cells that have the potential to form tumors remains problematic. The derivation of scalable (self-renewing) embryonic progenitor stem cell lines offers a solution because they are well defined and clonally pure. Clonally pure progenitor stem cell lines also provide a means for identifying cell surface targeting reagents that are useful for identification, tracking, and repeated derivation of the corresponding progenitor stem cell types from additional hPS cell sources. Such stem cell targeting reagents can then be applied to the manufacture of genetically diverse banks of human embryonic progenitor cell lines for drug screening, disease modeling, and cell therapy. Here we present methods to identify human embryonic progenitor stem cell targeting peptides by selection of phage display libraries on clonal embryonic progenitor cell lines and demonstrate their use for targeting quantum dots (Qdots) for stem cell labeling.

A Nanoparticle Carrying the p53 Gene Targets Tumors Including Cancer Stem Cells, Sensitizes Glioblastoma to Chemotherapy and Improves Survival

PubMed Central

2015-01-01

Temozolomide (TMZ)-resistance in glioblastoma multiforme (GBM) has been linked to upregulation of O6-methylguanine-DNA methyltransferase (MGMT). Wild-type (wt) p53 was previously shown to down-modulate MGMT. However, p53 therapy for GBM is limited by lack of efficient delivery across the blood brain barrier (BBB). We have developed a systemic nanodelivery platform (scL) for tumor-specific targeting (primary and metastatic), which is currently in multiple clinical trials. This self-assembling nanocomplex is formed by simple mixing of the components in a defined order and a specific ratio. Here, we demonstrate that scL crosses the BBB and efficiently targets GBM, as well as cancer stem cells (CSCs), which have been implicated in recurrence and treatment resistance in many human cancers. Moreover, systemic delivery of scL-p53 down-modulates MGMT and induces apoptosis in intracranial GBM xenografts. The combination of scL-p53 and TMZ increased the antitumor efficacy of TMZ with enhanced survival benefit in a mouse model of highly TMZ-resistant GBM. scL-p53 also sensitized both CSCs and bulk tumor cells to TMZ, increasing apoptosis. These results suggest that combining scL-p53 with standard TMZ treatment could be a more effective therapy for GBM. PMID:24811110

Highly Sensitive Detection of Target Biomolecules on Cell Surface Using Gold Nanoparticle Conjugated with Aptamer Probe

NASA Astrophysics Data System (ADS)

Kim, Hyonchol; Terazono, Hideyuki; Hayashi, Masahito; Takei, Hiroyuki; Yasuda, Kenji

2012-06-01

A method of gold nanoparticle (Au NP) labeling with backscattered electron (BE) imaging of field emission scanning electron microscopy (FE-SEM) was applied for specific detection of target biomolecules on a cell surface. A single-stranded DNA aptamer, which specifically binds to the target molecule on a human acute lymphoblastic leukemia cell, was conjugated with a 20 nm Au NP and used as a probe to label its target molecule on the cell. The Au NP probe was incubated with the cell, and the interaction was confirmed using BE imaging of FE-SEM through direct counting of the number of Au NPs attached on the target cell surface. Specific Au NP-aptamer probes were observed on a single cell surface and their spatial distributions including submicron-order localizations were also clearly visualized, whereas the nonspecific aptamer probes were not observed on it. The aptamer probe can be potentially dislodged from the cell surface with treatment of nucleases, indicating that Au NP-conjugated aptamer probes can be used as sensitive and reversible probes to label target biomolecules on cells.

The Quest for Targets Executing MYC-Dependent Cell Transformation.

PubMed

Hartl, Markus

2016-01-01

MYC represents a transcription factor with oncogenic potential converting multiple cellular signals into a broad transcriptional response, thereby controlling the expression of numerous protein-coding and non-coding RNAs important for cell proliferation, metabolism, differentiation, and apoptosis. Constitutive activation of MYC leads to neoplastic cell transformation, and deregulated MYC alleles are frequently observed in many human cancer cell types. Multiple approaches have been performed to isolate genes differentially expressed in cells containing aberrantly activated MYC proteins leading to the identification of thousands of putative targets. Functional analyses of genes differentially expressed in MYC-transformed cells had revealed that so far more than 40 upregulated or downregulated MYC targets are actively involved in cell transformation or tumorigenesis. However, further systematic and selective approaches are required for determination of the known or yet unidentified targets responsible for processing the oncogenic MYC program. The search for critical targets in MYC-dependent tumor cells is exacerbated by the fact that during tumor development, cancer cells progressively evolve in a multistep process, thereby acquiring their characteristic features in an additive manner. Functional expression cloning, combinatorial gene expression, and appropriate in vivo tests could represent adequate tools for dissecting the complex scenario of MYC-specified cell transformation. In this context, the central goal is to identify a minimal set of targets that suffices to phenocopy oncogenic MYC. Recently developed genomic editing tools could be employed to confirm the requirement of crucial transformation-associated targets. Knowledge about essential MYC-regulated genes is beneficial to expedite the development of specific inhibitors to interfere with growth and viability of human tumor cells in which MYC is aberrantly activated. Approaches based on the principle of

The Quest for Targets Executing MYC-Dependent Cell Transformation

PubMed Central

Hartl, Markus

2016-01-01

MYC represents a transcription factor with oncogenic potential converting multiple cellular signals into a broad transcriptional response, thereby controlling the expression of numerous protein-coding and non-coding RNAs important for cell proliferation, metabolism, differentiation, and apoptosis. Constitutive activation of MYC leads to neoplastic cell transformation, and deregulated MYC alleles are frequently observed in many human cancer cell types. Multiple approaches have been performed to isolate genes differentially expressed in cells containing aberrantly activated MYC proteins leading to the identification of thousands of putative targets. Functional analyses of genes differentially expressed in MYC-transformed cells had revealed that so far more than 40 upregulated or downregulated MYC targets are actively involved in cell transformation or tumorigenesis. However, further systematic and selective approaches are required for determination of the known or yet unidentified targets responsible for processing the oncogenic MYC program. The search for critical targets in MYC-dependent tumor cells is exacerbated by the fact that during tumor development, cancer cells progressively evolve in a multistep process, thereby acquiring their characteristic features in an additive manner. Functional expression cloning, combinatorial gene expression, and appropriate in vivo tests could represent adequate tools for dissecting the complex scenario of MYC-specified cell transformation. In this context, the central goal is to identify a minimal set of targets that suffices to phenocopy oncogenic MYC. Recently developed genomic editing tools could be employed to confirm the requirement of crucial transformation-associated targets. Knowledge about essential MYC-regulated genes is beneficial to expedite the development of specific inhibitors to interfere with growth and viability of human tumor cells in which MYC is aberrantly activated. Approaches based on the principle of

Targeting of HPV-16+ Epithelial Cancer Cells by TCR Gene Engineered T Cells Directed against E6.

PubMed

Draper, Lindsey M; Kwong, Mei Li M; Gros, Alena; Stevanović, Sanja; Tran, Eric; Kerkar, Sid; Raffeld, Mark; Rosenberg, Steven A; Hinrichs, Christian S

2015-10-01

The E6 and E7 oncoproteins of HPV-associated epithelial cancers are in principle ideal immunotherapeutic targets, but evidence that T cells specific for these antigens can recognize and kill HPV(+) tumor cells is limited. We sought to determine whether TCR gene engineered T cells directed against an HPV oncoprotein can successfully target HPV(+) tumor cells. T-cell responses against the HPV-16 oncoproteins were investigated in a patient with an ongoing 22-month disease-free interval after her second resection of distant metastatic anal cancer. T cells genetically engineered to express an oncoprotein-specific TCR from this patient's tumor-infiltrating T cells were tested for specific reactivity against HPV(+) epithelial tumor cells. We identified, from an excised metastatic anal cancer tumor, T cells that recognized an HLA-A*02:01-restricted epitope of HPV-16 E6. The frequency of the dominant T-cell clonotype from these cells was approximately 400-fold greater in the patient's tumor than in her peripheral blood. T cells genetically engineered to express the TCR from this clonotype displayed high avidity for an HLA-A*02:01-restricted epitope of HPV-16, and they showed specific recognition and killing of HPV-16(+) cervical, and head and neck cancer cell lines. These findings demonstrate that HPV-16(+) tumors can be targeted by E6-specific TCR gene engineered T cells, and they provide the foundation for a novel cellular therapy directed against HPV-16(+) malignancies, including cervical, oropharyngeal, anal, vulvar, vaginal, and penile cancers. ©2015 American Association for Cancer Research.

Targeting human breast cancer cells by an oncolytic adenovirus using microRNA-targeting strategy.

PubMed

Shayestehpour, Mohammad; Moghim, Sharareh; Salimi, Vahid; Jalilvand, Somayeh; Yavarian, Jila; Romani, Bizhan; Mokhtari-Azad, Talat

2017-08-15

MicroRNA-targeting strategy is a promising approach that enables oncolytic viruses to replicate in tumor cells but not in normal cells. In this study, we targeted adenoviral replication toward breast cancer cells by inserting ten complementary binding sites for miR-145-5p downstream of E1A gene. In addition, we evaluated the effect of increasing miR-145 binding sites on inhibition of virus replication. Ad5-control and adenoviruses carrying five or ten copies of miR145-5p target sites (Ad5-5miR145T, Ad5-10miR145T) were generated and inoculated into MDA-MB-453, BT-20, MCF-7 breast cancer cell lines and human mammary epithelial cells (HMEpC). Titer of Ad5-10miR145T in HMEpC was significantly lower than Ad5-control titer. Difference between the titer of these two viruses at 12, 24, 36, and 48h after infection was 1.25, 2.96, 3.06, and 3.77 log TCID 50 . No significant difference was observed between the titer of both adenoviruses in MDA-MB-453, BT-20 and MCF-7 cells. The infectious titer of adenovirus containing 10 miR-145 binding sites in HMEpC cells at 24, 36, and 48h post-infection was 1.7, 2.08, and 4-fold, respectively, lower than the titer of adenovirus carrying 5 miR-145 targets. Our results suggest that miR-145-targeting strategy provides selectivity for adenovirus replication in breast cancer cells. Increasing the number of miRNA binding sites within the adenoviral genome confers more selectivity for viral replication in cancer cells. Copyright © 2017. Published by Elsevier B.V.

Cell cycle-tailored targeting of metastatic melanoma: Challenges and opportunities.

PubMed

Haass, Nikolas K; Gabrielli, Brian

2017-07-01

The advent of targeted therapies of metastatic melanoma, such as MAPK pathway inhibitors and immune checkpoint antagonists, has turned dermato-oncology from the "bad guy" to the "poster child" in oncology. Current targeted therapies are effective, although here is a clear need to develop combination therapies to delay the onset of resistance. Many antimelanoma drugs impact on the cell cycle but are also dependent on certain cell cycle phases resulting in cell cycle phase-specific drug insensitivity. Here, we raise the question: Have combination trials been abandoned prematurely as ineffective possibly only because drug scheduling was not optimized? Firstly, if both drugs of a combination hit targets in the same melanoma cell, cell cycle-mediated drug insensitivity should be taken into account when planning combination therapies, timing of dosing schedules and choice of drug therapies in solid tumors. Secondly, if the combination is designed to target different tumor cell subpopulations of a heterogeneous tumor, one drug effective in a particular subpopulation should not negatively impact on the other drug targeting another subpopulation. In addition to the role of cell cycle stage and progression on standard chemotherapeutics and targeted drugs, we discuss the utilization of cell cycle checkpoint control defects to enhance chemotherapeutic responses or as targets themselves. We propose that cell cycle-tailored targeting of metastatic melanoma could further improve therapy outcomes and that our real-time cell cycle imaging 3D melanoma spheroid model could be utilized as a tool to measure and design drug scheduling approaches. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sonoporation of endothelial cells by vibrating targeted microbubbles.

PubMed

Kooiman, Klazina; Foppen-Harteveld, Miranda; van der Steen, Antonius F W; de Jong, Nico

2011-08-25

Molecular imaging using ultrasound makes use of targeted microbubbles. In this study we investigated whether these microbubbles could also be used to induce sonoporation in endothelial cells. Lipid-coated microbubbles were targeted to CD31 and insonified at 1 MHz at low peak negative acoustic pressures at six sequences of 10 cycle sine-wave bursts. Vibration of the targeted microbubbles was recorded with the Brandaris-128 high-speed camera (~13 million frames per second). In total, 31 cells were studied that all had one microbubble (1.2-4.2 micron in diameter) attached per cell. After insonification at 80 kPa, 30% of the cells (n=6) had taken up propidium iodide, while this was 20% (n=1) at 120 kPa and 83% (n=5) at 200 kPa. Irrespective of the peak negative acoustic pressure, uptake of propidium iodide was observed when the relative vibration amplitude of targeted microbubbles was greater than 0.5. No relationship was found between the position of the microbubble on the cell and induction of sonoporation. This study shows that targeted microbubbles can also be used to induce sonoporation, thus making it possible to combine molecular imaging and drug delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

Targeted silver nanoparticles for ratiometric cell phenotyping

NASA Astrophysics Data System (ADS)

Willmore, Anne-Mari A.; Simón-Gracia, Lorena; Toome, Kadri; Paiste, Päärn; Kotamraju, Venkata Ramana; Mölder, Tarmo; Sugahara, Kazuki N.; Ruoslahti, Erkki; Braun, Gary B.; Teesalu, Tambet

2016-04-01

Affinity targeting is used to deliver nanoparticles to cells and tissues. For efficient targeting, it is critical to consider the expression and accessibility of the relevant receptors in the target cells. Here, we describe isotopically barcoded silver nanoparticles (AgNPs) as a tool for auditing affinity ligand receptors in cells. Tumor penetrating peptide RPARPAR (receptor: NRP-1) and tumor homing peptide GKRK (receptor: p32) were used as affinity ligands on the AgNPs. The binding and uptake of the peptide-functionalized AgNPs by cultured PPC-1 prostate cancer and M21 melanoma cells was dependent on the cell surface expression of the cognate peptide receptors. Barcoded peptide-functionalized AgNPs were synthesized from silver and palladium isotopes. The cells were incubated with a cocktail of the barcoded nanoparticles [RPARPAR (R), GKRK (K), and control], and cellular binding and internalization of each type of nanoparticle was assessed by inductively coupled plasma mass spectrometry. The results of isotopic analysis were in agreement with data obtained using optical methods. Using ratiometric measurements, we were able to classify the PPC-1 cell line as mainly NRP-1-positive, with 75 +/- 5% R-AgNP uptake, and the M21 cell line as only p32-positive, with 89 +/- 9% K-AgNP uptake. The isotopically barcoded multiplexed AgNPs are useful as an in vitro ratiometric phenotyping tool and have potential uses in functional evaluation of the expression of accessible homing peptide receptors in vivo.Affinity targeting is used to deliver nanoparticles to cells and tissues. For efficient targeting, it is critical to consider the expression and accessibility of the relevant receptors in the target cells. Here, we describe isotopically barcoded silver nanoparticles (AgNPs) as a tool for auditing affinity ligand receptors in cells. Tumor penetrating peptide RPARPAR (receptor: NRP-1) and tumor homing peptide GKRK (receptor: p32) were used as affinity ligands on the AgNPs. The

A novel double-targeted nondrug delivery system for targeting cancer stem cells

PubMed Central

Qiao, Shupei; Zhao, Yufang; Geng, Shuai; Li, Yong; Hou, Xiaolu; Liu, Yi; Lin, Feng-Huei; Yao, Lifen; Tian, Weiming

2016-01-01

Instead of killing cancer stem cells (CSCs), the conventional chemotherapy used for cancer treatment promotes the enrichment of CSCs, which are responsible for tumor growth, metastasis, and recurrence. However, most therapeutic agents are only able to kill a small proportion of CSCs by targeting one or two cell surface markers or dysregulated CSC pathways, which are usually shared with normal stem cells (NSCs). In this study, we developed a novel nondrug delivery system for the dual targeting of CSCs by conjugating hyaluronic acid (HA) and grafting the doublecortin-like kinase 1 (DCLK1) monoclonal antibody to the surface of poly(ethylene glycol) (PEG)–poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs), which can specifically target CD44 receptors and the DCLK1 surface marker – the latter was shown to possess the capacity to distinguish between CSCSs and NSCs. The size and morphology of these NPs were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). This was followed by studies of NP encapsulation efficiency and in vitro drug release properties. Then, the cytotoxicity of the NPs was tested via Cell Counting Kit-8 assay. Finally, the 4T1 CSCs were obtained from the alginate-based platform, which we developed as an in vitro tumor model. Tumor-bearing nude mice were used as in vivo models to systematically detect the ability of NPs to target CSCs. Our results showed that the DCLK1–HA–PEG–PLGA NPs exhibited a targeting effect toward CSCs both in vitro and in vivo. These findings have important implications for the rational design of drug delivery systems that target CSCs with high efficacy. PMID:27994463

Advanced cell therapies: targeting, tracking and actuation of cells with magnetic particles.

PubMed

Connell, John J; Patrick, P Stephen; Yu, Yichao; Lythgoe, Mark F; Kalber, Tammy L

2015-01-01

Regenerative medicine would greatly benefit from a new platform technology that enabled measurable, controllable and targeting of stem cells to a site of disease or injury in the body. Superparamagnetic iron-oxide nanoparticles offer attractive possibilities in biomedicine and can be incorporated into cells, affording a safe and reliable means of tagging. This review describes three current and emerging methods to enhance regenerative medicine using magnetic particles to guide therapeutic cells to a target organ; track the cells using MRI and assess their spatial localization with high precision and influence the behavior of the cell using magnetic actuation. This approach is complementary to the systemic injection of cell therapies, thus expanding the horizon of stem cell therapeutics.

Approaches for targeting self-renewal pathways in cancer stem cells: implications for hematological treatments.

PubMed

Horne, Gillian A; Copland, Mhairi

2017-05-01

Self-renewal is considered a defining property of stem cells. Self-renewal is essential in embryogenesis and normal tissue repair and homeostasis. However, in cancer, self-renewal pathways, e.g. WNT, NOTCH, Hedgehog and BMP, frequently become de-regulated in stem cells, or more mature progenitor cells acquire self-renewal properties, resulting in abnormal tissue growth and tumorigenesis. Areas covered: This review considers the conserved embryonic self-renewal pathways, including WNT, NOTCH, Hedgehog and BMP. The article describes recent advances in our understanding of these pathways in leukemia and, more specifically, leukemia stem cells (LSC), how these pathways cross-talk and interact with the LSC microenvironment, and discusses the clinical implications and potential therapeutic strategies, both in preclinical and in clinical trials for hematological malignancies. Expert opinion: The conserved embryonic self-renewal pathways are frequently de-regulated in cancer stem cells (CSC), including LSCs. There is significant cross-talk between self-renewal pathways, and their downstream targets, and the microenvironment. Effective targeting of these pathways is challenging due to cross-talk, and importantly, because these pathways are important for normal stem cells as well as CSC, adverse effects on normal tissues may mean a therapeutic window cannot be identified. Nonetheless, several agents targeting these pathways are currently in clinical trials in hematological malignancies.

Review of the current targeted therapies for non-small-cell lung cancer

PubMed Central

Nguyen, Kim-Son H; Neal, Joel W; Wakelee, Heather

2014-01-01

The last decade has witnessed the development of oncogene-directed targeted therapies that have significantly changed the treatment of non-small-cell lung cancer (NSCLC). In this paper we review the data demonstrating efficacy of gefitinib, erlotinib, and afatinib, which target the epidermal growth factor receptor (EGFR), and crizotinib which targets anaplastic lymphoma kinase (ALK). We discuss the challenge of acquired resistance to these small-molecular tyrosine kinase inhibitors and review promising agents which may overcome resistance, including the EGFR T790M-targeted agents CO-1686 and AZD9291, and the ALK-targeted agents ceritinib (LDK378), AP26113, alectinib (CH/RO5424802), and others. Emerging therapies directed against other driver oncogenes in NSCLC including ROS1, HER2, and BRAF are covered as well. The identification of specific molecular targets in a significant fraction of NSCLC has led to the personalized deployment of many effective targeted therapies, with more to come. PMID:25302162

Re-programming tumour cell metabolism to treat cancer: no lone target for lonidamine.

PubMed

Bhutia, Yangzom D; Babu, Ellappan; Ganapathy, Vadivel

2016-06-01

Tumour cell metabolism is very different from normal cell metabolism; cancer cells re-programme the metabolic pathways that occur in normal cells in such a manner that it optimizes their proliferation, growth and survival. Although this metabolic re-programming obviously operates to the advantage of the tumour, it also offers unique opportunities for effective cancer therapy. Molecules that target the tumour cell-specific metabolic pathways have potential as novel anti-cancer drugs. Lonidamine belongs to this group of molecules and is already in use in some countries for cancer treatment. It has been known for a long time that lonidamine interferes with energy production in tumour cells by inhibiting hexokinase II (HKII), a glycolytic enzyme. However, subsequent studies have uncovered additional pharmacological targets for the drug, which include the electron transport chain and the mitochondrial permeability transition pore, thus expanding the pharmacological effects of the drug on tumour cell metabolism. A study by Nancolas et al. in a recent issue of the Biochemical Journal identifies two additional new targets for lonidamine: the pyruvate transporter in the mitochondria and the H(+)-coupled monocarboxylate transporters in the plasma membrane (PM). It is thus becoming increasingly apparent that the anti-cancer effects of lonidamine do not occur through a single target; the drug works at multiple sites. Irrespective of the molecular targets, what lonidamine does in the end is to undo what the tumour cells have done in terms of re-programming cellular metabolism and mitochondrial function. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Development of a Recombinant Multifunctional Biomacromolecule for Targeted Gene Transfer to Prostate Cancer Cells.

PubMed

Hatefi, Arash; Karjoo, Zahra; Nomani, Alireza

2017-09-11

The objective of this study was to genetically engineer a fully functional single chain fusion peptide composed of motifs from diverse biological and synthetic origins that can perform multiple tasks including DNA condensation, cell targeting, cell transfection, particle shielding from immune system and effective gene transfer to prostate tumors. To achieve the objective, a single chain biomacromolecule (vector) consisted of four repeatative units of histone H2A peptide, fusogenic peptide GALA, short elastin-like peptide, and PC-3 cell targeting peptide was designed. To examine the functionality of each motif in the vector sequence, it was characterized in terms of size and zeta potential by Zetasizer, PC-3 cell targeting and transfection by flowcytometry, IgG induction by immunogenicity assay, and PC-3 tumor transfection by quantitative live animal imaging. Overall, the results of this study showed the possibility of using genetic engineering techniques to program various functionalities into one single chain vector and create a multifunctional nonimmunogenic biomacromolecule for targeted gene transfer to prostate cancer cells. This proof-of-concept study is a significant step forward toward creating a library of vectors for targeted gene transfer to any cancer cell type at both in vitro and in vivo levels.

PEGylated PLGA-based nanoparticles targeting M cells for oral vaccination.

PubMed

Garinot, Marie; Fiévez, Virginie; Pourcelle, Vincent; Stoffelbach, François; des Rieux, Anne; Plapied, Laurence; Theate, Ivan; Freichels, Hélène; Jérôme, Christine; Marchand-Brynaert, Jacqueline; Schneider, Yves-Jacques; Préat, Véronique

2007-07-31

To improve the efficiency of orally delivered vaccines, PEGylated PLGA-based nanoparticles displaying RGD molecules at their surface were designed to target human M cells. RGD grafting was performed by an original method called "photografting" which covalently linked RGD peptides mainly on the PEG moiety of the PCL-PEG, included in the formulation. First, three non-targeted formulations with size and zeta potential adapted to M cell uptake and stable in gastro-intestinal fluids, were developed. Their transport by an in vitro model of the human Follicle associated epithelium (co-cultures) was largely increased as compared to mono-cultures (Caco-2 cells). RGD-labelling of nanoparticles significantly increased their transport by co-cultures, due to interactions between the RGD ligand and the beta(1) intregrins detected at the apical surface of co-cultures. In vivo studies demonstrated that RGD-labelled nanoparticles particularly concentrated in M cells. Finally, ovalbumin-loaded nanoparticles were orally administrated to mice and induced an IgG response, attesting antigen ability to elicit an immune response after oral delivery.

Targeting Leukemia Stem Cells in the Bone Marrow Niche

PubMed Central

Bornhäuser, Martin

2018-01-01

The bone marrow (BM) niche encompasses multiple cells of mesenchymal and hematopoietic origin and represents a unique microenvironment that is poised to maintain hematopoietic stem cells. In addition to its role as a primary lymphoid organ through the support of lymphoid development, the BM hosts various mature lymphoid cell types, including naïve T cells, memory T cells and plasma cells, as well as mature myeloid elements such as monocyte/macrophages and neutrophils, all of which are crucially important to control leukemia initiation and progression. The BM niche provides an attractive milieu for tumor cell colonization given its ability to provide signals which accelerate tumor cell proliferation and facilitate tumor cell survival. Cancer stem cells (CSCs) share phenotypic and functional features with normal counterparts from the tissue of origin of the tumor and can self-renew, differentiate and initiate tumor formation. CSCs possess a distinct immunological profile compared with the bulk population of tumor cells and have evolved complex strategies to suppress immune responses through multiple mechanisms, including the release of soluble factors and the over-expression of molecules implicated in cancer immune evasion. This chapter discusses the latest advancements in understanding of the immunological BM niche and highlights current and future immunotherapeutic strategies to target leukemia CSCs and overcome therapeutic resistance in the clinic. PMID:29466292

An innovative pre-targeting strategy for tumor cell specific imaging and therapy

NASA Astrophysics Data System (ADS)

Qin, Si-Yong; Peng, Meng-Yun; Rong, Lei; Jia, Hui-Zhen; Chen, Si; Cheng, Si-Xue; Feng, Jun; Zhang, Xian-Zheng

2015-08-01

A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the ``biotin-avidin'' interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging and therapeutic agents for tumor treatments.A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the ``biotin-avidin'' interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging

Successes and limitations of targeted therapies in renal cell carcinoma.

PubMed

Pracht, Marc; Berthold, Dominik

2014-01-01

Until recently, the standard treatment for metastatic renal cell carcinoma (RCC) was nonspecific immunotherapy based on interleukin-2 or interferon-α. This was associated with a modest survival benefit and with significant clinical toxicities. The understanding of numerous molecular pathways in RCC, including HIF, VEGF, mTOR, and the consecutive use of targeted therapies since the beginning of 2005 have significantly improved outcomes for patients with metastatic RCC with an overall survival greater than 2 years. At present, at least 7 targeted agents are approved for first and consecutive lines of treatment of clear cell metastatic RCC. Long-term benefit and extended survival may be achieved through the optimal use of targeted therapies: optimal dosing, adverse event management and treatment duration and compliance. Advances in the finding of prognostic factors highlight the potential for personalizing treatment for patients with metastatic RCC. Data regarding the best sequencing of targeted therapies, predictive biomarkers, best timing of surgery, patient risk profiles, understanding of resistance mechanisms and safety of targeted therapies are growing and will provide a further step ahead in the management of advanced RCC. In parallel, a new class of therapeutics is emerging in RCC: immunotherapy; in particular check-point blockade antibodies are showing very promising results. © 2014 S. Karger AG, Basel.

Improved and targeted delivery of bioactive molecules to cells with magnetic layer-by-layer assembled microcapsules

NASA Astrophysics Data System (ADS)

Pavlov, Anton M.; Gabriel, Samantha A.; Sukhorukov, Gleb B.; Gould, David J.

2015-05-01

Despite our increasing knowledge of cell biology and the recognition of an increasing repertoire of druggable intracellular therapeutic targets, there remain a limited number of approaches to deliver bioactive molecules to cells and even fewer that enable targeted delivery. Layer-by-layer (LbL) microcapsules are assembled using alternate layers of oppositely charged molecules and are potential cell delivery vehicles for applications in nanomedicine. There are a wide variety of charged molecules that can be included in the microcapsule structure including metal nanoparticles that introduce physical attributes. Delivery of bioactive molecules to cells with LbL microcapsules has recently been demonstrated, so in this study we explore the delivery of bioactive molecules (luciferase enzyme and plasmid DNA) to cells using biodegradable microcapsules containing a layer of magnetite nanoparticles. Interestingly, significantly improved intracellular luciferase enzyme activity (25 fold) and increased transfection efficiency with plasmid DNA (3.4 fold) was observed with magnetic microcapsules. The use of a neodymium magnet enabled efficient targeting of magnetic microcapsules which further improved the delivery efficiency of the cargoes as a consequence of increased microcapsule concentration at the magnetic site. Microcapsules were well tolerated by cells in these experiments and only displayed signs of toxicity at a capsule : cell ratio of 100 : 1 and with extended exposure. These studies illustrate how multi-functionalization of LbL microcapsules can improve and target delivery of bioactive molecules to cells.

Targeting Stromal Recruitment by Prostate Cancer Cells

DTIC Science & Technology

2006-03-01

Ensinger, C., Tumer , Z., Tommerup, N. et al.: Hedgehog signaling in small-cell lung cancer : frequent in vivo but a rare event in vitro. Lung Cancer , 52...W81XWH-04-1-0157 TITLE: Targeting Stromal Recruitment by Prostate Cancer Cells PRINCIPAL INVESTIGATOR: Jingxian Zhang, Ph.D...DATES COVERED (From - To) 15 Feb 2004 – 14 Feb 2006 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Targeting Stromal Recruitment by Prostate Cancer

Characterization of aldehyde dehydrogenase 1 high ovarian cancer cells: Towards targeted stem cell therapy.

PubMed

Sharrow, Allison C; Perkins, Brandy; Collector, Michael I; Yu, Wayne; Simons, Brian W; Jones, Richard J

2016-08-01

The cancer stem cell (CSC) paradigm hypothesizes that successful clinical eradication of CSCs may lead to durable remission for patients with ovarian cancer. Despite mounting evidence in support of ovarian CSCs, their phenotype and clinical relevance remain unclear. We and others have found high aldehyde dehydrogenase 1 (ALDH(high)) expression in a variety of normal and malignant stem cells, and sought to better characterize ALDH(high) cells in ovarian cancer. We compared ALDH(high) to ALDH(low) cells in two ovarian cancer models representing distinct subtypes: FNAR-C1 cells, derived from a spontaneous rat endometrioid carcinoma, and the human SKOV3 cell line (described as both serous and clear cell subtypes). We assessed these populations for stem cell features then analyzed expression by microarray and qPCR. ALDH(high) cells displayed CSC properties, including: smaller size, quiescence, regenerating the phenotypic diversity of the cell lines in vitro, lack of contact inhibition, nonadherent growth, multi-drug resistance, and in vivo tumorigenicity. Microarray and qPCR analysis of the expression of markers reported by others to enrich for ovarian CSCs revealed that ALDH(high) cells of both models showed downregulation of CD24, but inconsistent expression of CD44, KIT and CD133. However, the following druggable targets were consistently expressed in the ALDH(high) cells from both models: mTOR signaling, her-2/neu, CD47 and FGF18/FGFR3. Based on functional characterization, ALDH(high) ovarian cancer cells represent an ovarian CSC population. Differential gene expression identified druggable targets that have the potential for therapeutic efficacy against ovarian CSCs from multiple subtypes. Copyright © 2016 Elsevier Inc. All rights reserved.

Planar optical waveguide based sandwich assay sensors and processes for the detection of biological targets including early detection of cancers

DOEpatents

Martinez, Jennifer S [Santa Fe, NM; Swanson, Basil I [Los Alamos, NM; Shively, John E [Arcadia, CA; Li, Lin [Monrovia, CA

2009-06-02

An assay element is described including recognition ligands adapted for binding to carcinoembryonic antigen (CEA) bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of CEA is described including injecting a possible CEA-containing sample into a sensor cell including the assay element, maintaining the sample within the sensor cell for time sufficient for binding to occur between CEA present within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.

Target-cancer cell specific activatable fluorescence imaging Probes: Rational Design and in vivo Applications

PubMed Central

Kobayashi, Hisataka; Choyke, Peter L.

2010-01-01

CONSPECTUS Conventional imaging methods, such as angiography, computed tomography, magnetic resonance imaging and radionuclide imaging, rely on contrast agents (iodine, gadolinium, radioisotopes) that are “always on”. While these agents have proven clinically useful, they are not sufficiently sensitive because of the inadequate target to background ratio. A unique aspect of optical imaging is that fluorescence probes can be designed to be activatable, i.e. only “turned on” under certain conditions. These probes can be designed to emit signal only after binding a target tissue, greatly increasing sensitivity and specificity in the detection of disease. There are two basic types of activatable fluorescence probes; 1) conventional enzymatically activatable probes, which exist in the quenched state until activated by enzymatic cleavage mostly outside of the cells, and 2) newly designed target-cell specific activatable probes, which are quenched until activated in targeted cells by endolysosomal processing that results when the probe binds specific cell-surface receptors and is subsequently internalized. Herein, we present a review of the rational design and in vivo applications of target-cell specific activatable probes. Designing these probes based on their photo-chemical (e.g. activation strategy), pharmacological (e.g. biodistribution), and biological (e.g. target specificity) properties has recently allowed the rational design and synthesis of target-cell specific activatable fluorescence imaging probes, which can be conjugated to a wide variety of targeting molecules. Several different photo-chemical mechanisms have been utilized, each of which offers a unique capability for probe design. These include: self-quenching, homo- and hetero-fluorescence resonance energy transfer (FRET), H-dimer formation and photon-induced electron transfer (PeT). In addition, the repertoire is further expanded by the option for reversibility or irreversibility of the signal

Magnetic stem cell targeting to the inner ear

NASA Astrophysics Data System (ADS)

Le, T. N.; Straatman, L.; Yanai, A.; Rahmanian, R.; Garnis, C.; Häfeli, U. O.; Poblete, T.; Westerberg, B. D.; Gregory-Evans, K.

2017-12-01

Severe sensorineural deafness is often accompanied by a loss of auditory neurons in addition to injury of the cochlear epithelium and hair cell loss. Cochlear implant function however depends on a healthy complement of neurons and their preservation is vital in achieving optimal results. We have developed a technique to target mesenchymal stem cells (MSCs) to a deafened rat cochlea. We then assessed the neuroprotective effect of systematically delivered MSCs on the survival and function of spiral ganglion neurons (SGNs). MSCs were labeled with superparamagnetic nanoparticles, injected via the systemic circulation, and targeted using a magnetized cochlea implant and external magnet. Neurotrophic factor concentrations, survival of SGNs, and auditory function were assessed at 1 week and 4 weeks after treatments and compared against multiple control groups. Significant numbers of magnetically targeted MSCs (>30 MSCs/section) were present in the cochlea with accompanied elevation of brain-derived neurotrophic factor and glial cell-derived neurotrophic factor levels (p < 0.001). In addition we saw improved survival of SGNs (approximately 80% survival at 4 weeks). Hearing threshold levels in magnetically targeted rats were found to be significantly better than those of control rats (p < 0.05). These results indicate that magnetic targeting of MSCs to the cochlea can be accomplished with a magnetized cochlear permalloy implant and an external magnet. The targeted stem cells release neurotrophic factors which results in improved SGN survival and hearing recovery. Combining magnetic cell-based therapy and cochlear implantation may improve cochlear implant function in treating deafness.

Chimeric antigen receptor T cells targeting Fc μ receptor selectively eliminate CLL cells while sparing healthy B cells.

PubMed

Faitschuk, Elena; Hombach, Andreas A; Frenzel, Lukas P; Wendtner, Clemens-Martin; Abken, Hinrich

2016-09-29

Adoptive cell therapy of chronic lymphocytic leukemia (CLL) with chimeric antigen receptor (CAR)-modified T cells targeting CD19 induced lasting remission of this refractory disease in a number of patients. However, the treatment is associated with prolonged "on-target off-tumor" toxicities due to the targeted elimination of healthy B cells demanding more selectivity in targeting CLL cells. We identified the immunoglobulin M Fc receptor (FcμR), also known as the Fas apoptotic inhibitory molecule-3 or TOSO, as a target for a more selective treatment of CLL by CAR T cells. FcμR is highly and consistently expressed by CLL cells; only minor levels are detected on healthy B cells or other hematopoietic cells. T cells with a CAR specific for FcμR efficiently responded toward CLL cells, released a panel of proinflammatory cytokines and lytic factors, like soluble FasL and granzyme B, and eliminated the leukemic cells. In contrast to CD19 CAR T cells, anti-FcμR CAR T cells did not attack healthy B cells. T cells with anti-FcμR CAR delayed outgrowth of Mec-1-induced leukemia in a xenograft mouse model. T cells from CLL patients in various stages of the disease, modified by the anti-FcμR CAR, purged their autologous CLL cells in vitro without reducing the number of healthy B cells, which is the case with anti-CD19 CAR T cells. Compared with the currently used therapies, the data strongly imply a superior therapeutic index of anti-FcμR CAR T cells for the treatment of CLL. © 2016 by The American Society of Hematology.

Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dudás, József, E-mail: jozsef.dudas@i-med.ac.at; Fullár, Alexandra, E-mail: fullarsz@gmail.com; 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest

Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factormore » κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells.« less

Cell-type-specific, Aptamer-functionalized Agents for Targeted Disease Therapy

PubMed Central

Zhou, Jiehua; Rossi, John J.

2014-01-01

One hundred years ago, Dr. Paul Ehrlich popularized the “magic bullet” concept for cancer therapy in which an ideal therapeutic agent would only kill the specific tumor cells it targeted. Since then, “targeted therapy” that specifically targets the molecular defects responsible for a patient's condition has become a long-standing goal for treating human disease. However, safe and efficient drug delivery during the treatment of cancer and infectious disease remains a major challenge for clinical translation and the development of new therapies. The advent of SELEX technology has inspired many groundbreaking studies that successfully adapted cell-specific aptamers for targeted delivery of active drug substances in both in vitro and in vivo models. By covalently linking or physically functionalizing the cell-specific aptamers with therapeutic agents, such as siRNA, microRNA, chemotherapeutics or toxins, or delivery vehicles, such as organic or inorganic nanocarriers, the targeted cells and tissues can be specifically recognized and the therapeutic compounds internalized, thereby improving the local concentration of the drug and its therapeutic efficacy. Currently, many cell-type-specific aptamers have been developed that can target distinct diseases or tissues in a cell-type-specific manner. In this review, we discuss recent advances in the use of cell-specific aptamers for targeted disease therapy, as well as conjugation strategies and challenges. PMID:24936916

Trispecific antibodies for CD16A-directed NK cell engagement and dual-targeting of tumor cells.

PubMed

Gantke, Thorsten; Weichel, Michael; Herbrecht, Carmen; Reusch, Uwe; Ellwanger, Kristina; Fucek, Ivica; Eser, Markus; Müller, Thomas; Griep, Remko; Molkenthin, Vera; Zhukovsky, Eugene A; Treder, Martin

2017-09-01

Bispecific antibodies that redirect the lytic activity of cytotoxic immune effector cells, such as T- and NK cells, onto tumor cells have emerged as a highly attractive and clinically validated treatment modality for hematological malignancies. Advancement of this therapeutic concept into solid tumor indications, however, is hampered by the scarcity of targetable antigens that are surface-expressed on tumor cells but demonstrate only limited expression on healthy tissues. To overcome this limitation, the concept of dual-targeting, i.e. the simultaneous targeting of two tumor-expressed surface antigens with limited co-expression on non-malignant cells, with multispecific antibodies has been proposed to increase tumor selectivity of antibody-induced effector cell cytotoxicity. Here, a novel CD16A (FcγRIIIa)-directed trispecific, tetravalent antibody format, termed aTriFlex, is described, that is capable of redirecting NK cell cytotoxicity to two surface-expressed antigens. Using a BCMA/CD200-based in vitro model system, the potential use of aTriFlex antibodies for dual-targeting and selective induction of NK cell-mediated target cell lysis was investigated. Bivalent bispecific target cell binding was found to result in significant avidity gains and up to 17-fold increased in vitro potency. These data suggest trispecific aTriFlex antibodies may support dual-targeting strategies to redirect NK cell cytotoxicity with increased selectivity to enable targeting of solid tumor antigens. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Dendritic cell targeted vaccines: Recent progresses and challenges

PubMed Central

Chen, Pengfei; Liu, Xinsheng; Sun, Yuefeng; Zhou, Peng; Wang, Yonglu; Zhang, Yongguang

2016-01-01

ABSTRACT Dendritic cells (DCs) are known to be a set of morphology, structure and function of heterogeneous professional antigen presenting cells (APCs), as well as the strongest functional antigen presenting cells, which can absorb, process and present antigens. As the key regulators of innate and adaptive immune responses, DCs are at the center of the immune system and capable of interacting with both B cells and T cells, thereby manipulating the humoral and cellular immune responses. DCs provide an essential link between the innate and adaptive immunity, and the strong immune activation function of DCs and their properties of natural adjuvants, make them a valuable target for antigen delivery. Targeting antigens to DC-specific endocytic receptors in combination with the relevant antibodies or ligands along with immunostimulatory adjuvants has been recently recognized as a promising strategy for designing an effective vaccine that elicits a strong and durable T cell response against intracellular pathogens and cancer. This opinion article provides a brief summary of the rationales, superiorities and challenges of existing DC-targeting approaches. PMID:26513200

Targeting Mantle Cell Lymphoma with Anti-SYK Nanoparticles

PubMed Central

Cely, Ingrid; Yiv, Seang; Yin, Qian; Shahidzadeh, Anoush; Tang, Li; Cheng, Jianjun; Uckun, Fatih M.

2013-01-01

The pentapeptide mimic 1,4-bis(9-O-dihydroquinidinyl)phthalazine / hydroquinidine 1,4-phathalazinediyl diether (“compound 61”) (C-61) is the first reported inhibitor targeting the P-site of SYK. Here we report a nanotechnology platform to target C-61 to mantle cell lymphoma (MCL) cells. Liposomal nanoparticles (NP) loaded with C-61 were prepared using the standard thin film evaporation method. The entrapment of C-61 was obtained using the pH gradient procedure with lactobionic acid (LBA) being used as a low pH buffer inside the NP. Formulation F6A was selected as a lead candidate for further biological testing. The average diameter, zeta potential and C-61 content of the F6A NP was 40 nm, 0.1 mV, and 12.6 mg/ml, respectively. F6A induces apoptosis in SYK+ but not SYK− leukemia/lymphoma cells. We also evaluated the cytotoxic activity of F6A in the context of an in vitro artificial bone marrow assay platform based on a 3D scaffold with inverted colloidal crystal geometry mimicking the structural topology of actual bone marrow matrix. The ability of C-61 to induce apoptosis in ALL-1 cells was not adversely affected by the scaffolds. F6A, but not the drug-free NP formulation F6B, caused apoptosis of MCL cell lines MAVER-1 and MINO within 24h. Further development of rationally designed SYK inhibitors and their nanoscale formulations may provide the foundation for therapeutic innovation against a broad spectrum of lymphoid malignancies, including MCL. PMID:23730399

Selective tumor cell targeting by the disaccharide moiety of bleomycin.

PubMed

Yu, Zhiqiang; Schmaltz, Ryan M; Bozeman, Trevor C; Paul, Rakesh; Rishel, Michael J; Tsosie, Krystal S; Hecht, Sidney M

2013-02-27

In a recent study, the well-documented tumor targeting properties of the antitumor agent bleomycin (BLM) were studied in cell culture using microbubbles that had been derivatized with multiple copies of BLM. It was shown that BLM selectively targeted MCF-7 human breast carcinoma cells but not the "normal" breast cell line MCF-10A. Furthermore, it was found that the BLM analogue deglycobleomycin, which lacks the disaccharide moiety of BLM, did not target either cell line, indicating that the BLM disaccharide moiety is necessary for tumor selectivity. Not resolved in the earlier study were the issues of whether the BLM disaccharide moiety alone is sufficient for tumor cell targeting and the possible cellular uptake of the disaccharide. In the present study, we conjugated BLM, deglycoBLM, and BLM disaccharide to the cyanine dye Cy5**. It was found that the BLM and BLM disaccharide conjugates, but not the deglycoBLM conjugate, bound selectively to MCF-7 cells and were internalized. The same was also true for the prostate cancer cell line DU-145 (but not for normal PZ-HPV-7 prostate cells) and for the pancreatic cancer cell line BxPC-3 (but not for normal SVR A221a pancreas cells). The targeting efficiency of the disaccharide was only slightly less than that of BLM in MCF-7 and DU-145 cells and comparable to that of BLM in BxPC-3 cells. These results establish that the BLM disaccharide is both necessary and sufficient for tumor cell targeting, a finding with obvious implications for the design of novel tumor imaging and therapeutic agents.

Nanoparticle-macrophage interactions: A balance between clearance and cell-specific targeting

PubMed Central

Rattan, Rahul; Bhattacharjee, Somnath; Zong, Hong; Swain, Corban; Siddiqui, Muneeb A.; Visovatti, Scott H.; Kanthi, Yogendra; Desai, Sajani; Pinsky, David J.; Goonewardena, Sascha N.

2017-01-01

The surface properties of nanoparticles (NPs) are a major factor that influences how these nanomaterials interact with biological systems. Interactions between NPs and macrophages of the reticuloendothelial system (RES) can reduce the efficacy of NP diagnostics and therapeutics. Traditionally, to limit NP clearance by the RES system, the NP surface is neutralized with molecules like poly(ethylene glycol) (PEG) which are known to resist protein adsorption and RES clearance. Unfortunately, PEG modification is not without drawbacks including difficulties with the synthesis and associations with immune reactions. To overcome some of these obstacles, we neutralized the NP surface by acetylation and compared this modification to PEGylation for RES clearance and tumor-specific targeting. We found that acetylation was comparable to PEGylation in reducing RES clearance. Additionally, we found that dendrimer acetylation did not impact folic acid (FA)-mediated targeting of tumor cells whereas PEG surface modification reduced the targeting ability of the NP. These results clarify the impact of different NP surface modifications on RES clearance and cell-specific targeting and provide insights into the design of more effective NPs. PMID:28705434

An innovative pre-targeting strategy for tumor cell specific imaging and therapy.

PubMed

Qin, Si-Yong; Peng, Meng-Yun; Rong, Lei; Jia, Hui-Zhen; Chen, Si; Cheng, Si-Xue; Feng, Jun; Zhang, Xian-Zheng

2015-09-21

A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the "biotin-avidin" interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging and therapeutic agents for tumor treatments.

Strategies to target non-T-cell HIV reservoirs.

PubMed

Sacha, Jonah B; Ndhlovu, Lishomwa C

2016-07-01

A central question for the HIV cure field is to determine new ways to target clinically relevant, latently and actively replicating HIV-infected cells beyond resting memory CD4 T cells, particularly in anatomical areas of low drug penetrability. HIV eradication strategies being positioned for targeting HIV for extinction in the CD4 T-cell compartment may also show promise in non-CD4 T-cells reservoirs. Furthermore, several exciting novel therapeutic approaches specifically focused on HIV clearance from non-CD4 T-cell populations are being developed. Although reservoir validity in these non-CD4 T cells continues to remain debated, this review will highlight recent advances and make an argument as to their clinical relevancy as we progress towards an HIV cure.

Heat-shock proteins as dendritic cell-targeting vaccines – getting warmer

PubMed Central

McNulty, Shaun; Colaco, Camilo A; Blandford, Lucy E; Bailey, Christopher R; Baschieri, Selene; Todryk, Stephen

2013-01-01

Heat-shock proteins (hsp) provide a natural link between innate and adaptive immune responses by combining the ideal properties of antigen carriage (chaperoning), targeting and activation of antigen-presenting cells (APC), including dendritic cells (DC). Targeting is achieved through binding of hsp to distinct cell surface receptors and is followed by antigen internalization, processing and presentation. An improved understanding of the interaction of hsp with DC has driven the development of numerous hsp-containing vaccines, designed to deliver antigens directly to DC. Studies in mice have shown that for cancers, such vaccines generate impressive immune responses and protection from tumour challenge. However, translation to human use, as for many experimental immunotherapies, has been slow partly because of the need to perform trials in patients with advanced cancers, where demonstration of efficacy is challenging. Recently, the properties of hsp have been used for development of prophylactic vaccines against infectious diseases including tuberculosis and meningitis. These hsp-based vaccines, in the form of pathogen-derived hsp–antigen complexes, or recombinant hsp combined with selected antigens in vitro, offer an innovative approach against challenging diseases where broad antigen coverage is critical. PMID:23551234

Potential targets for lung squamous cell carcinoma

Cancer.gov

Researchers have identified potential therapeutic targets in lung squamous cell carcinoma, the second most common form of lung cancer. The Cancer Genome Atlas (TCGA) Research Network study comprehensively characterized the lung squamous cell carcinoma gen

N-acetylgalactosamine-functionalized dendrimers as hepatic cancer cell-targeted carriers.

PubMed

Medina, Scott H; Tekumalla, Venkatesh; Chevliakov, Maxim V; Shewach, Donna S; Ensminger, William D; El-Sayed, Mohamed E H

2011-06-01

There is an urgent need for novel polymeric carriers that can selectively deliver a large dose of chemotherapeutic agents into hepatic cancer cells to achieve high therapeutic activity with minimal systemic side effects. PAMAM dendrimers are characterized by a unique branching architecture and a large number of chemical surface groups suitable for coupling of chemotherapeutic agents. In this article, we report the coupling of N-acetylgalactosamine (NAcGal) to generation 5 (G5) of poly(amidoamine) (PAMAM-NH₂) dendrimers via peptide and thiourea linkages to prepare NAcGal-targeted carriers used for targeted delivery of chemotherapeutic agents into hepatic cancer cells. We describe the uptake of NAcGal-targeted and non-targeted G5 dendrimers into hepatic cancer cells (HepG2) as a function of G5 concentration and incubation time. We examine the contribution of the asialoglycoprotein receptor (ASGPR) to the internalization of NAcGal-targeted dendrimers into hepatic cancer cells through a competitive inhibition assay. Our results show that uptake of NAcGal-targeted G5 dendrimers into hepatic cancer cells occurs via ASGPR-mediated endocytosis. Internalization of these targeted carriers increased with the increase in G5 concentration and incubation time following Michaelis-Menten kinetics characteristic of receptor-mediated endocytosis. These results collectively indicate that G5-NAcGal conjugates function as targeted carriers for selective delivery of chemotherapeutic agents into hepatic cancer cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

Targeting the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway: an emerging treatment strategy for squamous cell lung carcinoma.

PubMed

Beck, Joseph Thaddeus; Ismail, Amen; Tolomeo, Christina

2014-09-01

Squamous cell lung carcinoma accounts for approximately 30% of all non-small cell lung cancers (NSCLCs). Despite progress in the understanding of the biology of cancer, cytotoxic chemotherapy remains the standard of care for patients with squamous cell lung carcinoma, but the prognosis is generally poor. The phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is one of the most commonly activated signaling pathways in cancer, leading to cell proliferation, survival, and differentiation. It has therefore become a major focus of clinical research. Various alterations in the PI3K/AKT/mTOR pathway have been identified in squamous cell lung carcinoma and a number of agents targeting these alterations are in clinical development for use as single agents and in combination with other targeted and conventional treatments. These include pan-PI3K inhibitors, isoform-specific PI3K inhibitors, AKT inhibitors, mTOR inhibitors, and dual PI3K/mTOR inhibitors. These agents have demonstrated antitumor activity in preclinical models of NSCLC and preliminary clinical evidence is also available for some agents. This review will discuss the role of the PI3K/AKT/mTOR pathway in cancer and how the discovery of genetic alterations in this pathway in patients with squamous cell lung carcinoma can inform the development of targeted therapies for this disease. An overview of ongoing clinical trials investigating PI3K/AKT/mTOR pathway inhibitors in squamous cell lung carcinoma will also be included. Copyright © 2014 Elsevier Ltd. All rights reserved.

Targeting the adenosine 2A receptor enhances chimeric antigen receptor T cell efficacy

PubMed Central

Beavis, Paul A.; Henderson, Melissa A.; Giuffrida, Lauren; Mills, Jane K.; Sek, Kevin; Cross, Ryan S.; Davenport, Alexander J.; John, Liza B.; Mardiana, Sherly; Slaney, Clare Y.; Johnstone, Ricky W.; Trapani, Joseph A.; Stagg, John; Loi, Sherene; Kats, Lev; Gyorki, David; Kershaw, Michael H.; Darcy, Phillip K.

2017-01-01

Chimeric antigen receptor (CAR) T cells have been highly successful in treating hematological malignancies, including acute and chronic lymphoblastic leukemia. However, treatment of solid tumors using CAR T cells has been largely unsuccessful to date, partly because of tumor-induced immunosuppressive mechanisms, including adenosine production. Previous studies have shown that adenosine generated by tumor cells potently inhibits endogenous antitumor T cell responses through activation of adenosine 2A receptors (A2ARs). Herein, we have observed that CAR activation resulted in increased A2AR expression and suppression of both murine and human CAR T cells. This was reversible using either A2AR antagonists or genetic targeting of A2AR using shRNA. In 2 syngeneic HER2+ self-antigen tumor models, we found that either genetic or pharmacological targeting of the A2AR profoundly increased CAR T cell efficacy, particularly when combined with PD-1 blockade. Mechanistically, this was associated with increased cytokine production of CD8+ CAR T cells and increased activation of both CD8+ and CD4+ CAR T cells. Given the known clinical relevance of the CD73/adenosine pathway in several solid tumor types, and the initiation of phase I trials for A2AR antagonists in oncology, this approach has high translational potential to enhance CAR T cell efficacy in several cancer types. PMID:28165340

IDENTIFYING AND TARGETING TUMOR-INITIATING CELLS IN THE TREATMENT OF BREAST CANCER

PubMed Central

Wei, Wei; Lewis, Michael T.

2015-01-01

Breast cancer is the most common cancer in women (exclusive of skin cancer), and is the second leading cause of cancer-related deaths. Although conventional and targeted therapies have improved survival rates, there are still considerable challenges in treating breast cancer, including treatment resistance, disease recurrence, and metastasis. Treatment resistance can be either de novo - due to traits that tumor cells possess prior to treatment, or acquired, - due to traits that tumor cells gain in response to treatment. A recently proposed mechanism of de novo resistance invokes existence of a specialized subset of cancer cells defined as tumor-initiating cells (TICs), or cancer stem cells (CSC). TICs have the capacity to self-renew and regenerate new tumors that consist of all clonally-derived cell types present in the parental tumor. There are data to suggest that TICs are resistant to many conventional cancer therapies, and survive treatment in spite of dramatic shrinkage of the tumor. Residual TICs can then eventually regrow resulting in disease relapse. It is also hypothesized that TIC may be responsible for metastatic disease. If these hypotheses are correct, targeting TICs may be imperative to achieve cure. In this review, we discuss evidence for breast TICs and their apparent resistance to conventional chemotherapy and radiotherapy, as well as to various targeted therapies. We also address the potential impact of breast TIC plasticity and metastatic potential on therapeutic strategies. Finally, we describe several genes and signaling pathways that appear important for TIC function that may represent promising therapeutic targets. PMID:25876646

Cell cycle proteins as promising targets in cancer therapy.

PubMed

Otto, Tobias; Sicinski, Piotr

2017-01-27

Cancer is characterized by uncontrolled tumour cell proliferation resulting from aberrant activity of various cell cycle proteins. Therefore, cell cycle regulators are considered attractive targets in cancer therapy. Intriguingly, animal models demonstrate that some of these proteins are not essential for proliferation of non-transformed cells and development of most tissues. By contrast, many cancers are uniquely dependent on these proteins and hence are selectively sensitive to their inhibition. After decades of research on the physiological functions of cell cycle proteins and their relevance for cancer, this knowledge recently translated into the first approved cancer therapeutic targeting of a direct regulator of the cell cycle. In this Review, we focus on proteins that directly regulate cell cycle progression (such as cyclin-dependent kinases (CDKs)), as well as checkpoint kinases, Aurora kinases and Polo-like kinases (PLKs). We discuss the role of cell cycle proteins in cancer, the rationale for targeting them in cancer treatment and results of clinical trials, as well as the future therapeutic potential of various cell cycle inhibitors.

Targeting Aberrant Glutathione Metabolism to Eradicate Human Acute Myelogenous Leukemia Cells*

PubMed Central

Pei, Shanshan; Minhajuddin, Mohammad; Callahan, Kevin P.; Balys, Marlene; Ashton, John M.; Neering, Sarah J.; Lagadinou, Eleni D.; Corbett, Cheryl; Ye, Haobin; Liesveld, Jane L.; O'Dwyer, Kristen M.; Li, Zheng; Shi, Lei; Greninger, Patricia; Settleman, Jeffrey; Benes, Cyril; Hagen, Fred K.; Munger, Joshua; Crooks, Peter A.; Becker, Michael W.; Jordan, Craig T.

2013-01-01

The development of strategies to eradicate primary human acute myelogenous leukemia (AML) cells is a major challenge to the leukemia research field. In particular, primitive leukemia cells, often termed leukemia stem cells, are typically refractory to many forms of therapy. To investigate improved strategies for targeting of human AML cells we compared the molecular mechanisms regulating oxidative state in primitive (CD34+) leukemic versus normal specimens. Our data indicate that CD34+ AML cells have elevated expression of multiple glutathione pathway regulatory proteins, presumably as a mechanism to compensate for increased oxidative stress in leukemic cells. Consistent with this observation, CD34+ AML cells have lower levels of reduced glutathione and increased levels of oxidized glutathione compared with normal CD34+ cells. These findings led us to hypothesize that AML cells will be hypersensitive to inhibition of glutathione metabolism. To test this premise, we identified compounds such as parthenolide (PTL) or piperlongumine that induce almost complete glutathione depletion and severe cell death in CD34+ AML cells. Importantly, these compounds only induce limited and transient glutathione depletion as well as significantly less toxicity in normal CD34+ cells. We further determined that PTL perturbs glutathione homeostasis by a multifactorial mechanism, which includes inhibiting key glutathione metabolic enzymes (GCLC and GPX1), as well as direct depletion of glutathione. These findings demonstrate that primitive leukemia cells are uniquely sensitive to agents that target aberrant glutathione metabolism, an intrinsic property of primary human AML cells. PMID:24089526

Targeting Notch, Hedgehog, and Wnt pathways in cancer stem cells: clinical update

PubMed Central

Miele, Lucio; Harris, Pamela Jo; Jeong, Woondong; Bando, Hideaki; Kahn, Michael; Yang, Sherry X.

2015-01-01

During the past decade, cancer stem cells (CSCs) have been increasingly identified in many malignancies. Although the origin and plasticity of these cells remain controversial, tumour heterogeneity and the presence of small populations of cells with stem-like characteristics is established in most malignancies. CSCs display many features of embryonic or tissue stem cells, and typically demonstrate persistent activation of one or more highly conserved signal transduction pathways involved in development and tissue homeostasis, including the Notch, Hedgehog (HH), and Wnt pathways. CSCs generally have slow growth rates and are resistant to chemotherapy and/or radiotherapy. Thus, new treatment strategies targeting these pathways to control stem-cell replication, survival and differentiation are under development. Herein, we provide an update on the latest advances in the clinical development of such approaches, and discuss strategies for overcoming CSC-associated primary or acquired resistance to cancer treatment. Given the crosstalk between the different embryonic developmental signalling pathways, as well as other pathways, designing clinical trials that target CSCs with rational combinations of agents to inhibit possible compensatory escape mechanisms could be of particular importance. We also share our views on the future directions for targeting CSCs to advance the clinical development of these classes of agents. PMID:25850553

Low-Dose Irradiation Enhances Gene Targeting in Human Pluripotent Stem Cells.

PubMed

Hatada, Seigo; Subramanian, Aparna; Mandefro, Berhan; Ren, Songyang; Kim, Ho Won; Tang, Jie; Funari, Vincent; Baloh, Robert H; Sareen, Dhruv; Arumugaswami, Vaithilingaraja; Svendsen, Clive N

2015-09-01

Human pluripotent stem cells (hPSCs) are now being used for both disease modeling and cell therapy; however, efficient homologous recombination (HR) is often crucial to develop isogenic control or reporter lines. We showed that limited low-dose irradiation (LDI) using either γ-ray or x-ray exposure (0.4 Gy) significantly enhanced HR frequency, possibly through induction of DNA repair/recombination machinery including ataxia-telangiectasia mutated, histone H2A.X and RAD51 proteins. LDI could also increase HR efficiency by more than 30-fold when combined with the targeting tools zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats. Whole-exome sequencing confirmed that the LDI administered to hPSCs did not induce gross genomic alterations or affect cellular viability. Irradiated and targeted lines were karyotypically normal and made all differentiated lineages that continued to express green fluorescent protein targeted at the AAVS1 locus. This simple method allows higher throughput of new, targeted hPSC lines that are crucial to expand the use of disease modeling and to develop novel avenues of cell therapy. The simple and relevant technique described in this report uses a low level of radiation to increase desired gene modifications in human pluripotent stem cells by an order of magnitude. This higher efficiency permits greater throughput with reduced time and cost. The low level of radiation also greatly increased the recombination frequency when combined with developed engineered nucleases. Critically, the radiation did not lead to increases in DNA mutations or to reductions in overall cellular viability. This novel technique enables not only the rapid production of disease models using human stem cells but also the possibility of treating genetically based diseases by correcting patient-derived cells. ©AlphaMed Press.

Adenovirus Vectors Target Several Cell Subtypes of Mammalian Inner Ear In Vivo

PubMed Central

Li, Wenyan; Shen, Jun

2016-01-01

Mammalian inner ear harbors diverse cell types that are essential for hearing and balance. Adenovirus is one of the major vectors to deliver genes into the inner ear for functional studies and hair cell regeneration. To identify adenovirus vectors that target specific cell subtypes in the inner ear, we studied three adenovirus vectors, carrying a reporter gene encoding green fluorescent protein (GFP) from two vendors or with a genome editing gene Cre recombinase (Cre), by injection into postnatal days 0 (P0) and 4 (P4) mouse cochlea through scala media by cochleostomy in vivo. We found three adenovirus vectors transduced mouse inner ear cells with different specificities and expression levels, depending on the type of adenoviral vectors and the age of mice. The most frequently targeted region was the cochlear sensory epithelium, including auditory hair cells and supporting cells. Adenovirus with GFP transduced utricular supporting cells as well. This study shows that adenovirus vectors are capable of efficiently and specifically transducing different cell types in the mammalian inner ear and provides useful tools to study inner ear gene function and to evaluate gene therapy to treat hearing loss and vestibular dysfunction. PMID:28116172

YSA-conjugated mesoporous silica nanoparticles effectively target EphA2-overexpressing breast cancer cells.

PubMed

Liu, Zhi; Tao, Zijian; Zhang, Qing; Wan, Song; Zhang, Fenglin; Zhang, Yan; Wu, Guanyu; Wang, Jiandong

2018-04-01

Neoadjuvant chemotherapy is commonly used to treat patients with locally advanced breast cancer and a common option for primary operable disease. However, systemic toxicity including cardiotoxicity and inefficient delivery are significant challenges form any chemotherapeutics. The development of targeted treatments that lower the risk of toxicity has, therefore, become an active area of research in the field of novel cancer therapeutics. Mesoporous silica nanoparticles (MSNs) have attracted significant attention as efficient drug delivery carriers, due to their high surface area and tailorable mesoporous structures. Eph receptors are the largest receptor tyrosine kinase family, which are divided into the A- and the B-type. Eph receptors play critical roles in embryonic development and human diseases including cancer. EphA2 is expressed in breast cancer cells and has roles in carcinogenesis, progression and prognosis of breast cancer. A homing peptide with the sequence YSAYPDSVPMMSK (YSA) that binds specifically to EphA2 was used to functionalize MSN. We focus on a novel EphA2-targeted delivery MSN system for breast cancer cells. We show that the EphA2 receptor is differentially expressed in breast cancer cells and highly expressed in the HER2-negative breast cancer cell line MCF7. Our results suggest that EphA2-targeted MSN for doxorubicin delivery (MSN-YSA-DOX) are more effective than MSN-DOX in treating breast cancer cell lines in vitro. Our preliminary observations suggest that the EphA2-targeted MSN delivery system may provide a strategy for enhancing delivery of therapeutic agents to breast cancer cells expressing EphA2, and potentially reduce toxicity while enhancing therapeutic efficacy.

Curcumin: a promising agent targeting cancer stem cells.

PubMed

Zang, Shufei; Liu, Tao; Shi, Junping; Qiao, Liang

2014-01-01

Cancer stem cells are a subset of cells that are responsible for cancer initiation and relapse. They are generally resistant to the current anticancer agents. Successful anticancer therapy must consist of approaches that can target not only the differentiated cancer cells, but also cancer stem cells. Emerging evidence suggested that the dietary agent curcumin exerted its anti-cancer activities via targeting cancer stem cells of various origins such as those of colorectal cancer, pancreatic cancer, breast cancer, brain cancer, and head and neck cancer. In order to enhance the therapeutic potential of curcumin, this agent has been modified or used in combination with other agents in the experimental therapy for many cancers. In this mini-review, we discussed the effect of curcumin and its derivatives in eliminating cancer stem cells and the possible underlying mechanisms.

Breast cancer stem cells, EMT and therapeutic targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kotiyal, Srishti; Bhattacharya, Susinjan, E-mail: s.bhattacharya@jiit.ac.in

Highlights: • Therapeutic targeting or inhibition of the key molecules of signaling pathways can control growth of breast cancer stem cells (BCSCs). • Development of BCSCs also involves miRNA interactions. • Therapeutic achievement can be done by targeting identified targets in the BCSC pathways. - Abstract: A small heterogeneous population of breast cancer cells acts as seeds to induce new tumor growth. These seeds or breast cancer stem cells (BCSCs) exhibit great phenotypical plasticity which allows them to undergo “epithelial to mesenchymal transition” (EMT) at the site of primary tumor and a future reverse transition. Apart from metastasis they aremore » also responsible for maintaining the tumor and conferring it with drug and radiation resistance and a tendency for post-treatment relapse. Many of the signaling pathways involved in induction of EMT are involved in CSC generation and regulation. Here we are briefly reviewing the mechanism of TGF-β, Wnt, Notch, TNF-α, NF-κB, RTK signalling pathways which are involved in EMT as well as BCSCs maintenance. Therapeutic targeting or inhibition of the key/accessory players of these pathways could control growth of BCSCs and hence malignant cancer. Additionally several miRNAs are dysregulated in cancer stem cells indicating their roles as oncogenes or tumor suppressors. This review also lists the miRNA interactions identified in BCSCs and discusses on some newly identified targets in the BCSC regulatory pathways like SHIP2, nicastrin, Pin 1, IGF-1R, pro-inflammatory cytokines and syndecan which can be targeted for therapeutic achievements.« less

MiR-188 Inhibits Glioma Cell Proliferation and Cell Cycle Progression through Targeting ß-catenin.

PubMed

Li, Nan; Shi, Hangyu; Zhang, Lu; Li, Xu; Gao, Lu; Zhang, Gang; Shi, Yongqiang; Guo, Shiwen

2017-12-21

MicroRNAs (miRNAs) play important roles in several human cancers. Although miR188 has been suggested to function as a tumor repressor in cancers, its precise role in glioma and the molecular mechanism remain unknown. In the present study, we investigated the effect of miR-188 on glioma and explored its relevant mechanisms. We found that the expression of miR-188 is dramatically downregulated in glioma tissues and cell lines. Subsequent investigation revealed that miR-188 expression was inversely correlated with ß-catenin expression in glioma tissue samples. Using a luciferase reporter assay, ß-catenin was determined to be a direct target of miR-188. Overexpression of miR-188 reduced ß-catenin expression at both the mRNA and protein levels, and inhibition of miR-188 increased ß-catenin expression. Moreover, we found that overexpression of miR-188 suppressed glioma cell proliferation and cell cycle G1-S transition, whereas inhibition of miR-188 promoted glioma cell proliferation. Importantly, silencing ß-catenin recapitulated the cellular and molecular effects seen upon miR-188 overexpression, which included inhibiting glioma cell proliferation and G1-S transition. Taken together, our results demonstrated that miR188 inhibits glioma cell proliferation by targeting ß-catenin, representing an effective therapeutic strategy for glioma.

Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells

PubMed Central

Oh, Se Jin; Noh, Kyung Hee; Lee, Young-Ho; Hong, Soon-Oh; Song, Kwon-Ho; Lee, Hyo-Jung; Kim, Soyeon; Kim, Tae Min; Jeon, Ju-Hong; Seo, Jae Hong; Kim, Dong-Wan; Kim, Tae Woo

2015-01-01

The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC. PMID:26517679

Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells.

PubMed

Oh, Se Jin; Noh, Kyung Hee; Lee, Young-Ho; Hong, Soon-Oh; Song, Kwon-Ho; Lee, Hyo-Jung; Kim, Soyeon; Kim, Tae Min; Jeon, Ju-Hong; Seo, Jae Hong; Kim, Dong-Wan; Kim, Tae Woo

2015-11-24

The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC.

Plasmonic nanobubbles for target cell-specific gene and drug delivery and multifunctional processing of heterogeneous cell systems

NASA Astrophysics Data System (ADS)

Lukianova-Hleb, Ekaterina Y.; Huye, Leslie E.; Brenner, Malcolm K.; Lapotko, Dmitri O.

2014-03-01

Cell and gene cancer therapies require ex vivo cell processing of human grafts. Such processing requires at least three steps - cell enrichment, cell separation (destruction), and gene transfer - each of which requires the use of a separate technology. While these technologies may be satisfactory for research use, they are of limited usefulness in the clinical treatment setting because they have a low processing rate, as well as a low transfection and separation efficacy and specificity in heterogeneous human grafts. Most problematic, because current technologies are administered in multiple steps - rather than in a single, multifunctional, and simultaneous procedure - they lengthen treatment process and introduce an unnecessary level of complexity, labor, and resources into clinical treatment; all these limitations result in high losses of valuable cells. We report a universal, high-throughput, and multifunctional technology that simultaneously (1) inject free external cargo in target cells, (2) destroys unwanted cells, and (3) preserve valuable non-target cells in heterogeneous grafts. Each of these functions has single target cell specificity in heterogeneous cell system, processing rate > 45 mln cell/min, injection efficacy 90% under 96% viability of the injected cells, target cell destruction efficacy > 99%, viability of not-target cells >99% The developed technology employs novel cellular agents, called plasmonic nanobubbles (PNBs). PNBs are not particles, but transient, intracellular events, a vapor nanobubbles that expand and collapse in mere nanoseconds under optical excitation of gold nanoparticles with short picosecond laser pulses. PNBs of different, cell-specific, size (1) inject free external cargo with small PNBs, (2) Destroy other target cells mechanically with large PNBs and (3) Preserve non-target cells. The multi-functionality, precision, and high throughput of all-in-one PNB technology will tremendously impact cell and gene therapies and other

Targeting of nucleotide-binding proteins by HAMLET--a conserved tumor cell death mechanism.

PubMed

Ho, J C S; Nadeem, A; Rydström, A; Puthia, M; Svanborg, C

2016-02-18

HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) kills tumor cells broadly suggesting that conserved survival pathways are perturbed. We now identify nucleotide-binding proteins as HAMLET binding partners, accounting for about 35% of all HAMLET targets in a protein microarray comprising 8000 human proteins. Target kinases were present in all branches of the Kinome tree, including 26 tyrosine kinases, 10 tyrosine kinase-like kinases, 13 homologs of yeast sterile kinases, 4 casein kinase 1 kinases, 15 containing PKA, PKG, PKC family kinases, 15 calcium/calmodulin-dependent protein kinase kinases and 13 kinases from CDK, MAPK, GSK3, CLK families. HAMLET acted as a broad kinase inhibitor in vitro, as defined in a screen of 347 wild-type, 93 mutant, 19 atypical and 17 lipid kinases. Inhibition of phosphorylation was also detected in extracts from HAMLET-treated lung carcinoma cells. In addition, HAMLET recognized 24 Ras family proteins and bound to Ras, RasL11B and Rap1B on the cytoplasmic face of the plasma membrane. Direct cellular interactions between HAMLET and activated Ras family members including Braf were confirmed by co-immunoprecipitation. As a consequence, oncogenic Ras and Braf activity was inhibited and HAMLET and Braf inhibitors synergistically increased tumor cell death in response to HAMLET. Unlike most small molecule kinase inhibitors, HAMLET showed selectivity for tumor cells in vitro and in vivo. The results identify nucleotide-binding proteins as HAMLET targets and suggest that dysregulation of the ATPase/kinase/GTPase machinery contributes to cell death, following the initial, selective recognition of HAMLET by tumor cells. The findings thus provide a molecular basis for the conserved tumoricidal effect of HAMLET, through dysregulation of kinases and oncogenic GTPases, to which tumor cells are addicted.

MiRNA-125a-5p inhibits glioblastoma cell proliferation and promotes cell differentiation by targeting TAZ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Jian; Xiao, Gelei; The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008

Highlights: • Expression of miR-125a-5p is inversely correlated with that of TAZ in glioma cells. • MiR-125a-5p represses TAZ expression in glioma cells. • MiR-125a-5p directly targets the 3′ UTR of TAZ mRNA and promotes its degradation. • MiR-125a-5p represses CTGF and survivin via TAZ, and inhibits glioma cell growth. • MiR-125a-5p inhibits the stem cell features of HFU-251 MG cells. - Abstract: Glioblastoma (GBM) is the most lethal brain tumor due to the resistance to conventional therapies, such as radiotherapy and chemotherapy. TAZ, an important mediator of the Hippo pathway, was found to be up-regulated in diverse cancers, includingmore » in GBM, and plays important roles in tumor initiation and progression. However, little is known about the regulation of TAZ expression in tumors. In this study, we found that miR-125a-5p is an important regulator of TAZ in glioma cells by directly targeting the TAZ 3′ UTR. MiR-125a-5p levels are inversely correlated with that of TAZ in normal astrocytes and a panel of glioma cell lines. MiR-125a-5p represses the expression of TAZ target genes, including CTGF and survivin, and inhibits cell proliferation and induces the differentiation of GBM cells; whereas over-expression of TAZ rescues the effects of miR-125a-5p. This study revealed a mechanism for TAZ deregulation in glioma cells, and also demonstrated a tumor suppressor role of miR-125a-5p in glioblastoma cells.« less

Targeting colon cancer stem cells using a new curcumin analogue, GO-Y030

PubMed Central

Lin, L; Liu, Y; Li, H; Li, P-K; Fuchs, J; Shibata, H; Iwabuchi, Y; Lin, J

2011-01-01

Background: Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer, including colon cancer. To date, whether STAT3 is activated and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, in colon cancer stem cells are still unknown. Methods: Flow cytometry was used to isolate colon cancer stem cells, which are characterised by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulations (ALDH+/CD133+). The levels of STAT3 phosphorylation and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, that targets STAT3 in colon cancer stem cells were examined. Results: Our results observed that ALDH+/CD133+ colon cancer cells expressed higher levels of phosphorylated STAT3 than ALDH-negative/CD133-negative colon cancer cells, suggesting that STAT3 is activated in colon cancer stem cells. GO-Y030 and curcumin inhibited STAT3 phosphorylation, cell viability, tumoursphere formation in colon cancer stem cells. GO-Y030 also reduced STAT3 downstream target gene expression and induced apoptosis in colon cancer stem cells. Furthermore, GO-Y030 suppressed tumour growth of cancer stem cells from both SW480 and HCT-116 colon cancer cell lines in the mouse model. Conclusion: Our results indicate that STAT3 is a novel therapeutic target in colon cancer stem cells, and inhibition of activated STAT3 in cancer stem cells by GO-Y030 may offer an effective treatment for colorectal cancer. PMID:21694723

Targeting colon cancer stem cells using a new curcumin analogue, GO-Y030.

PubMed

Lin, L; Liu, Y; Li, H; Li, P-K; Fuchs, J; Shibata, H; Iwabuchi, Y; Lin, J

2011-07-12

Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer, including colon cancer. To date, whether STAT3 is activated and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, in colon cancer stem cells are still unknown. Flow cytometry was used to isolate colon cancer stem cells, which are characterised by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulations (ALDH(+)/CD133(+)). The levels of STAT3 phosphorylation and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, that targets STAT3 in colon cancer stem cells were examined. Our results observed that ALDH(+)/CD133(+) colon cancer cells expressed higher levels of phosphorylated STAT3 than ALDH-negative/CD133-negative colon cancer cells, suggesting that STAT3 is activated in colon cancer stem cells. GO-Y030 and curcumin inhibited STAT3 phosphorylation, cell viability, tumoursphere formation in colon cancer stem cells. GO-Y030 also reduced STAT3 downstream target gene expression and induced apoptosis in colon cancer stem cells. Furthermore, GO-Y030 suppressed tumour growth of cancer stem cells from both SW480 and HCT-116 colon cancer cell lines in the mouse model. Our results indicate that STAT3 is a novel therapeutic target in colon cancer stem cells, and inhibition of activated STAT3 in cancer stem cells by GO-Y030 may offer an effective treatment for colorectal cancer.

The Mechanism of Gene Targeting in Human Somatic Cells

PubMed Central

Kan, Yinan; Ruis, Brian; Lin, Sherry; Hendrickson, Eric A.

2014-01-01

Gene targeting in human somatic cells is of importance because it can be used to either delineate the loss-of-function phenotype of a gene or correct a mutated gene back to wild-type. Both of these outcomes require a form of DNA double-strand break (DSB) repair known as homologous recombination (HR). The mechanism of HR leading to gene targeting, however, is not well understood in human cells. Here, we demonstrate that a two-end, ends-out HR intermediate is valid for human gene targeting. Furthermore, the resolution step of this intermediate occurs via the classic DSB repair model of HR while synthesis-dependent strand annealing and Holliday Junction dissolution are, at best, minor pathways. Moreover, and in contrast to other systems, the positions of Holliday Junction resolution are evenly distributed along the homology arms of the targeting vector. Most unexpectedly, we demonstrate that when a meganuclease is used to introduce a chromosomal DSB to augment gene targeting, the mechanism of gene targeting is inverted to an ends-in process. Finally, we demonstrate that the anti-recombination activity of mismatch repair is a significant impediment to gene targeting. These observations significantly advance our understanding of HR and gene targeting in human cells. PMID:24699519

Targeted cellular ablation based on the morphology of malignant cells

NASA Astrophysics Data System (ADS)

Ivey, Jill W.; Latouche, Eduardo L.; Sano, Michael B.; Rossmeisl, John H.; Davalos, Rafael V.; Verbridge, Scott S.

2015-11-01

Treatment of glioblastoma multiforme (GBM) is especially challenging due to a shortage of methods to preferentially target diffuse infiltrative cells, and therapy-resistant glioma stem cell populations. Here we report a physical treatment method based on electrical disruption of cells, whose action depends strongly on cellular morphology. Interestingly, numerical modeling suggests that while outer lipid bilayer disruption induced by long pulses (~100 μs) is enhanced for larger cells, short pulses (~1 μs) preferentially result in high fields within the cell interior, which scale in magnitude with nucleus size. Because enlarged nuclei represent a reliable indicator of malignancy, this suggested a means of preferentially targeting malignant cells. While we demonstrate killing of both normal and malignant cells using pulsed electric fields (PEFs) to treat spontaneous canine GBM, we proposed that properly tuned PEFs might provide targeted ablation based on nuclear size. Using 3D hydrogel models of normal and malignant brain tissues, which permit high-resolution interrogation during treatment testing, we confirmed that PEFs could be tuned to preferentially kill cancerous cells. Finally, we estimated the nuclear envelope electric potential disruption needed for cell death from PEFs. Our results may be useful in safely targeting the therapy-resistant cell niches that cause recurrence of GBM tumors.

Targeted cellular ablation based on the morphology of malignant cells

PubMed Central

Ivey, Jill W.; Latouche, Eduardo L.; Sano, Michael B.; Rossmeisl, John H.; Davalos, Rafael V.; Verbridge, Scott S.

2015-01-01

Treatment of glioblastoma multiforme (GBM) is especially challenging due to a shortage of methods to preferentially target diffuse infiltrative cells, and therapy-resistant glioma stem cell populations. Here we report a physical treatment method based on electrical disruption of cells, whose action depends strongly on cellular morphology. Interestingly, numerical modeling suggests that while outer lipid bilayer disruption induced by long pulses (~100 μs) is enhanced for larger cells, short pulses (~1 μs) preferentially result in high fields within the cell interior, which scale in magnitude with nucleus size. Because enlarged nuclei represent a reliable indicator of malignancy, this suggested a means of preferentially targeting malignant cells. While we demonstrate killing of both normal and malignant cells using pulsed electric fields (PEFs) to treat spontaneous canine GBM, we proposed that properly tuned PEFs might provide targeted ablation based on nuclear size. Using 3D hydrogel models of normal and malignant brain tissues, which permit high-resolution interrogation during treatment testing, we confirmed that PEFs could be tuned to preferentially kill cancerous cells. Finally, we estimated the nuclear envelope electric potential disruption needed for cell death from PEFs. Our results may be useful in safely targeting the therapy-resistant cell niches that cause recurrence of GBM tumors. PMID:26596248

Targeted delivery of peptide-conjugated biocompatible gold nanoparticles into cancer cell nucleus

NASA Astrophysics Data System (ADS)

Qian, Wei; Curry, Taeyjuana; Che, Yong; Kopelman, Raoul

2013-02-01

Nucleus remains a significant target for nanoparticles with diagnostic and therapeutic applications because both genetic information of the cell and transcription machinery reside there. Novel therapeutic strategies (for example, gene therapy), enabled by safe and efficient delivery of nanoparticles and drug molecules into the nucleus, are heralded by many as the ultimate treatment for severe and intractable diseases. However, most nanomaterials and macromolecules are incapable of reaching the cell nucleus on their own, because of biological barriers carefully honed by evolution including cellular membrane and nuclear envelope. In this paper, we have demonstrated an approach of fabrication of biocompatible gold nanoparticle (Au NP)-based vehicles which can entering into cancer cell nucleus by modifying Au NPs with both PEG 5000 and two different peptides (RGD and nuclear localization signal (NLS) peptide). The Au NPs used were fabricated via femtosecond laser ablation of Au bulk target in deionized water. The Au NPs produced by this method provide chemical free, virgin surface, which allows us to carry out "Sequential Conjugation" to modify their surface with PEG 5000, RGD, and NLS. "Sequential Conjugation" described in this presentation is very critical for the fabrication of Au NP-based vehicles capable of entering into cancer cell nucleus as it enables the engineering and tuning surface chemistries of Au NPs by independently adjusting amounts of PEG and peptides bound onto surface of Au NPs so as to maximize their nuclear targeting performance and biocompatibility regarding the cell line of interest. Both optical microscopy and transmission electron microscopy (TEM) are used to confirm the in vitro targeted nuclear delivery of peptide-conjugated biocompatible Au NPs by showing their presence in the cancer cell nucleus.

Electrochemical cell structure including an ionomeric barrier

DOEpatents

Lambert, Timothy N.; Hibbs, Michael

2017-06-20

An apparatus includes an electrochemical half-cell comprising: an electrolyte, an anode; and an ionomeric barrier positioned between the electrolyte and the anode. The anode may comprise a multi-electron vanadium phosphorous alloy, such as VP.sub.x, wherein x is 1-5. The electrochemical half-cell is configured to oxidize the vanadium and phosphorous alloy to release electrons. A method of mitigating corrosion in an electrochemical cell includes disposing an ionomeric barrier in a path of electrolyte or ion flow to an anode and mitigating anion accumulation on the surface of the anode.

Prodrug strategy for cancer cell-specific targeting: A recent overview.

PubMed

Zhang, Xian; Li, Xiang; You, Qidong; Zhang, Xiaojin

2017-10-20

The increasing development of targeted cancer therapy provides extensive possibilities in clinical trials, and numerous strategies have been explored. The prodrug is one of the most promising strategies in targeted cancer therapy to improve the selectivity and efficacy of cytotoxic compounds. Compared with normal tissues, cancer cells are characterized by unique aberrant markers, thus inactive prodrugs targeting these markers are excellent therapeutics to release active drugs, killing cancer cells without damaging normal tissues. In this review, we explore an integrated view of potential prodrugs applied in targeted cancer therapy based on aberrant cancer specific markers and some examples are provided for inspiring new ideas of prodrug strategy for cancer cell-specific targeting. Copyright © 2017. Published by Elsevier Masson SAS.

In Situ Target Engagement Studies in Adherent Cells.

PubMed

Axelsson, Hanna; Almqvist, Helena; Otrocka, Magdalena; Vallin, Michaela; Lundqvist, Sara; Hansson, Pia; Karlsson, Ulla; Lundbäck, Thomas; Seashore-Ludlow, Brinton

2018-04-20

A prerequisite for successful drugs is effective binding of the desired target protein in the complex environment of a living system. Drug-target engagement has typically been difficult to monitor in physiologically relevant models, and with current methods, especially, while maintaining spatial information. One recent technique for quantifying drug-target engagement is the cellular thermal shift assay (CETSA), in which ligand-induced protein stabilization is measured after a heat challenge. Here, we describe a CETSA protocol in live A431 cells for p38α (MAPK14), where remaining soluble protein is detected in situ, using high-content imaging in 384-well, microtiter plates. We validate this assay concept using a number of known p38α inhibitors and further demonstrate the potential of this technology for chemical probe and drug discovery purposes by performing a small pilot screen for novel p38α binders. Importantly, this protocol creates a workflow that is amenable to adherent cells in their native state and yields spatially resolved target engagement information measurable at the single-cell level.

Mitochondrial Targeted Coenzyme Q, Superoxide, and Fuel Selectivity in Endothelial Cells

PubMed Central

Fink, Brian D.; O'Malley, Yunxia; Dake, Brian L.; Ross, Nicolette C.; Prisinzano, Thomas E.; Sivitz, William I.

2009-01-01

Background Previously, we reported that the “antioxidant” compound “mitoQ” (mitochondrial-targeted ubiquinol/ubiquinone) actually increased superoxide production by bovine aortic endothelial (BAE) cell mitochondria incubated with complex I but not complex II substrates. Methods and Results To further define the site of action of the targeted coenzyme Q compound, we extended these studies to include different substrate and inhibitor conditions. In addition, we assessed the effects of mitoquinone on mitochondrial respiration, measured respiration and mitochondrial membrane potential in intact cells, and tested the intriguing hypothesis that mitoquinone might impart fuel selectivity in intact BAE cells. In mitochondria respiring on differing concentrations of complex I substrates, mitoquinone and rotenone had interactive effects on ROS consistent with redox cycling at multiple sites within complex I. Mitoquinone increased respiration in isolated mitochondria respiring on complex I but not complex II substrates. Mitoquinone also increased oxygen consumption by intact BAE cells. Moreover, when added to intact cells at 50 to 1000 nM, mitoquinone increased glucose oxidation and reduced fat oxidation, at doses that did not alter membrane potential or induce cell toxicity. Although high dose mitoquinone reduced mitochondrial membrane potential, the positively charged mitochondrial-targeted cation, decyltriphenylphosphonium (mitoquinone without the coenzyme Q moiety), decreased membrane potential more than mitoquinone, but did not alter fuel selectivity. Therefore, non-specific effects of the positive charge were not responsible and the quinone moiety is required for altered nutrient selectivity. Conclusions In summary, the interactive effects of mitoquinone and rotenone are consistent with redox cycling at more than one site within complex I. In addition, mitoquinone has substrate dependent effects on mitochondrial respiration, increases repiration by intact cells

Mitochondrial targeted coenzyme Q, superoxide, and fuel selectivity in endothelial cells.

PubMed

Fink, Brian D; O'Malley, Yunxia; Dake, Brian L; Ross, Nicolette C; Prisinzano, Thomas E; Sivitz, William I

2009-01-01

Previously, we reported that the "antioxidant" compound "mitoQ" (mitochondrial-targeted ubiquinol/ubiquinone) actually increased superoxide production by bovine aortic endothelial (BAE) cell mitochondria incubated with complex I but not complex II substrates. To further define the site of action of the targeted coenzyme Q compound, we extended these studies to include different substrate and inhibitor conditions. In addition, we assessed the effects of mitoquinone on mitochondrial respiration, measured respiration and mitochondrial membrane potential in intact cells, and tested the intriguing hypothesis that mitoquinone might impart fuel selectivity in intact BAE cells. In mitochondria respiring on differing concentrations of complex I substrates, mitoquinone and rotenone had interactive effects on ROS consistent with redox cycling at multiple sites within complex I. Mitoquinone increased respiration in isolated mitochondria respiring on complex I but not complex II substrates. Mitoquinone also increased oxygen consumption by intact BAE cells. Moreover, when added to intact cells at 50 to 1000 nM, mitoquinone increased glucose oxidation and reduced fat oxidation, at doses that did not alter membrane potential or induce cell toxicity. Although high dose mitoquinone reduced mitochondrial membrane potential, the positively charged mitochondrial-targeted cation, decyltriphenylphosphonium (mitoquinone without the coenzyme Q moiety), decreased membrane potential more than mitoquinone, but did not alter fuel selectivity. Therefore, non-specific effects of the positive charge were not responsible and the quinone moiety is required for altered nutrient selectivity. In summary, the interactive effects of mitoquinone and rotenone are consistent with redox cycling at more than one site within complex I. In addition, mitoquinone has substrate dependent effects on mitochondrial respiration, increases repiration by intact cells, and alters fuel selectivity favoring glucose over

Fragments of Target Cells are Internalized into Retroviral Envelope Protein-Expressing Cells during Cell-Cell Fusion by Endocytosis

PubMed Central

Izumida, Mai; Kamiyama, Haruka; Suematsu, Takashi; Honda, Eri; Koizumi, Yosuke; Yasui, Kiyoshi; Hayashi, Hideki; Ariyoshi, Koya; Kubo, Yoshinao

2016-01-01

Retroviruses enter into host cells by fusion between viral and host cell membranes. Retroviral envelope glycoprotein (Env) induces the membrane fusion, and also mediates cell-cell fusion. There are two types of cell-cell fusions induced by the Env protein. Fusion-from-within is induced by fusion between viral fusogenic Env protein-expressing cells and susceptible cells, and virions induce fusion-from-without by fusion between adjacent cells. Although entry of ecotropic murine leukemia virus (E-MLV) requires host cell endocytosis, the involvement of endocytosis in cell fusion is unclear. By fluorescent microscopic analysis of the fusion-from-within, we found that fragments of target cells are internalized into Env-expressing cells. Treatment of the Env-expressing cells with an endocytosis inhibitor more significantly inhibited the cell fusion than that of the target cells, indicating that endocytosis in Env-expressing cells is required for the cell fusion. The endocytosis inhibitor also attenuated the fusion-from-without. Electron microscopic analysis suggested that the membrane fusion resulting in fusion-from-within initiates in endocytic membrane dents. This study shows that two types of the viral cell fusion both require endocytosis, and provides the cascade of fusion-from-within. PMID:26834711

Estradiol targets T cell signaling pathways in human systemic lupus.

PubMed

Walters, Emily; Rider, Virginia; Abdou, Nabih I; Greenwell, Cindy; Svojanovsky, Stan; Smith, Peter; Kimler, Bruce F

2009-12-01

The major risk factor for developing systemic lupus erythematosus (SLE) is being female. The present study utilized gene profiles of activated T cells from females with SLE and healthy controls to identify signaling pathways uniquely regulated by estradiol that could contribute to SLE pathogenesis. Selected downstream pathway genes (+/- estradiol) were measured by real time polymerase chain amplification. Estradiol uniquely upregulated six pathways in SLE T cells that control T cell function including interferon-alpha signaling. Measurement of interferon-alpha pathway target gene expression revealed significant differences (p= 0.043) in DRIP150 (+/- estradiol) in SLE T cell samples while IFIT1 expression was bimodal and correlated moderately (r= 0.55) with disease activity. The results indicate that estradiol alters signaling pathways in activated SLE T cells that control T cell function. Differential expression of transcriptional coactivators could influence estrogen-dependent gene regulation in T cell signaling and contribute to SLE onset and disease pathogenesis.

microRNAs as Pharmacological Targets in Endothelial Cell Function and Dysfunction

PubMed Central

Chamorro-Jorganes, Aránzazu; Araldi, Elisa; Suárez, Yajaira

2013-01-01

Endothelial cell dysfunction is a term which implies the dysregulation of normal endothelial cell functions, including impairment of the barrier functions, control of vascular tone, disturbance of proliferative, migratory and morphogenic capacities of endothelial cells, as well as control of leukocyte trafficking. MicroRNAs (miRNAs) are short non-coding RNAs that have emerged as critical regulators of gene expression acting predominantly at the post-transcriptional level. This review summarizes the latest insights in the identification of endothelial-specific miRNAs and their targets, as well as their roles in controlling endothelial cell functions in both autocrine and paracrine manner. In addition, we discuss the therapeutic potential for the treatment of endothelial cell dysfunction and associated vascular pathophysiological conditions. PMID:23603154

Medulloblastoma stem cells: Promising targets in medulloblastoma therapy.

PubMed

Huang, Guo-Hao; Xu, Qing-Fu; Cui, You-Hong; Li, Ningning; Bian, Xiu-Wu; Lv, Sheng-Qing

2016-05-01

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Despite great improvements in the therapeutic regimen, relapse and leptomeningeal dissemination still pose great challenges to the long-term survival of MB patients. Developing more effective strategies has become extremely urgent. In recent years, a number of malignancies, including MB, have been found to contain a subpopulation of cancer cells known as cancer stem cells (CSCs), or tumor initiating/propagating cells. The CSCs are thought to be largely responsible for tumor initiation, maintenance, dissemination, and relapse; therefore, their pivotal roles have revealed them to be promising targets in MB therapy. Our growing understanding of the major medulloblastoma molecular subgroups and the derivation of some of these groups from specific stem or progenitor cells adds additional layers to the CSC knowledge base. Herein we review the current knowledge of MB stem cells, highlight the molecular mechanisms relating to MB relapse and leptomeningeal dissemination, and incorporate these with the need to develop more effective and accurate therapies for MB patients. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Structural features facilitating tumor cell targeting and internalization by bleomycin and its disaccharide.

PubMed

Yu, Zhiqiang; Paul, Rakesh; Bhattacharya, Chandrabali; Bozeman, Trevor C; Rishel, Michael J; Hecht, Sidney M

2015-05-19

We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide-cytotoxin conjugates.

Pros and Cons of Antigen-Presenting Cell Targeted Tumor Vaccines.

PubMed

Goyvaerts, Cleo; Breckpot, Karine

2015-01-01

In therapeutic antitumor vaccination, dendritic cells play the leading role since they decide if, how, when, and where a potent antitumor immune response will take place. Since the disentanglement of the complexity and merit of different antigen-presenting cell subtypes, antitumor immunotherapeutic research started to investigate the potential benefit of targeting these subtypes in situ. This review will discuss which antigen-presenting cell subtypes are at play and how they have been targeted and finally question the true meaning of targeting antitumor-based vaccines.

Purification-Free, Target-Selective Immobilization of a Protein from Cell Lysates.

PubMed

Cha, Jaehyun; Kwon, Inchan

2018-02-27

Protein immobilization has been widely used for laboratory experiments and industrial processes. Preparation of a recombinant protein for immobilization usually requires laborious and expensive purification steps. Here, a novel purification-free, target-selective immobilization technique of a protein from cell lysates is reported. Purification steps are skipped by immobilizing a target protein containing a clickable non-natural amino acid (p-azidophenylalanine) in cell lysates onto alkyne-functionalized solid supports via bioorthogonal azide-alkyne cycloaddition. In order to achieve a target protein-selective immobilization, p-azidophenylalanine was introduced into an exogenous target protein, but not into endogenous non-target proteins using host cells with amber codon-free genomic DNAs. Immobilization of superfolder fluorescent protein (sfGFP) from cell lysates is as efficient as that of the purified sfGFP. Using two fluorescent proteins (sfGFP and mCherry), the authors also demonstrated that the target proteins are immobilized with a minimal immobilization of non-target proteins (target-selective immobilization). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Strategic Therapeutic Targeting to Overcome Venetoclax Resistance in Aggressive B-cell Lymphomas.

PubMed

Pham, Lan V; Huang, Shengjian; Zhang, Hui; Zhang, Jun; Bell, Taylor; Zhou, Shouhao; Pogue, Elizabeth; Ding, Zhiyong; Lam, Laura; Westin, Jason; Davis, R Eric; Young, Ken H; Medeiros, L Jeffrey; Ford, Richard J; Nomie, Krystle; Zhang, Leo; Wang, Michael

2018-04-17

Purpose: B-cell lymphoma-2 (BCL-2), an antiapoptotic protein often dysregulated in B-cell lymphomas, promotes cell survival and provides protection from stress. A recent phase I first-in-human study of the BCL-2 inhibitor venetoclax in non-Hodgkin lymphoma showed an overall response rate of 44%. These promising clinical results prompted our examination of the biological effects and mechanism of action underlying venetoclax activity in aggressive B-cell lymphoma, including mantle cell lymphoma (MCL) and diffuse large B-cell lymphoma (DLBCL). Experimental Design: MCL and DLBCL cell lines, primary patient samples, and in vivo patient-derived xenograft (PDX) models were utilized to examine venetoclax efficacy. Furthermore, the mechanisms underlying venetoclax response and the development of venetoclax resistance were evaluated using proteomics analysis and Western blotting. Results: Potential biomarkers linked to venetoclax activity and targeted combination therapies that can augment venetoclax response were identified. We demonstrate that DLBCL and MCL cell lines, primary patient samples, and PDX mouse models expressing high BCL-2 levels are extremely sensitive to venetoclax treatment. Proteomics studies showed that venetoclax substantially alters the expression levels and phosphorylation status of key proteins involved in cellular processes, including the DNA damage response, cell metabolism, cell growth/survival, and apoptosis. Short- and long-term exposure to venetoclax inhibited PTEN expression, leading to enhanced AKT pathway activation and concomitant susceptibility to PI3K/AKT inhibition. Intrinsic venetoclax-resistant cells possess high AKT activation and are highly sensitive to PI3K/AKT inhibition. Conclusions: These findings demonstrate the on-target effect of venetoclax and offer potential mechanisms to overcome acquired and intrinsic venetoclax resistance through PI3K/AKT inhibition. Clin Cancer Res; 1-14. ©2018 AACR. ©2018 American Association for

T Cells that Recognize HPV Protein Can Target Virus-Infected Cells | Center for Cancer Research

Cancer.gov

Adoptive T-cell transfer (ACT) is a promising form of cancer immunotherapy. Treating patients with T cells isolated from a tumor and subsequently expanded in the lab can cause the complete regression of some melanomas and cervical cancers, but the treatment is currently restricted to a few cancer types. An approach that may be applied to a wider array of cancers involves modifying peripheral blood T cells with chimeric antigen receptors or T-cell receptors (TCR) that target specific tumor antigens. Unfortunately, epithelial cancers, which are the vast majority of cancers diagnosed, have proven difficult to treat this way because most identified antigens are shared with healthy tissues and targeting them leads to toxic side effects. However, cancers caused by persistent human papillomavirus (HPV) infection, including cervical, head and neck, anal, vaginal, vulvar, and penile cancers, may be particularly amenable to the latter form of ACT since the E6 and E7 viral proteins are essential for cancer formation but are not produced in normal tissues. To test this idea, Christian Hinrichs, M.D., and his colleagues examined tumor infiltrating lymphocytes (TILs) from a patient who experienced a prolonged disease-free period after her second surgical removal of metastatic anal cancer in the hopes of identifying a TCR against one of the HPV oncoproteins.

Lipoprotein-biomimetic nanostructure enables efficient targeting delivery of siRNA to Ras-activated glioblastoma cells via macropinocytosis

NASA Astrophysics Data System (ADS)

Huang, Jia-Lin; Jiang, Gan; Song, Qing-Xiang; Gu, Xiao; Hu, Meng; Wang, Xiao-Lin; Song, Hua-Hua; Chen, Le-Pei; Lin, Ying-Ying; Jiang, Di; Chen, Jun; Feng, Jun-Feng; Qiu, Yong-Ming; Jiang, Ji-Yao; Jiang, Xin-Guo; Chen, Hong-Zhuan; Gao, Xiao-Ling

2017-05-01

Hyperactivated Ras regulates many oncogenic pathways in several malignant human cancers including glioblastoma and it is an attractive target for cancer therapies. Ras activation in cancer cells drives protein internalization via macropinocytosis as a key nutrient-gaining process. By utilizing this unique endocytosis pathway, here we create a biologically inspired nanostructure that can induce cancer cells to `drink drugs' for targeting activating transcription factor-5 (ATF5), an overexpressed anti-apoptotic transcription factor in glioblastoma. Apolipoprotein E3-reconstituted high-density lipoprotein is used to encapsulate the siRNA-loaded calcium phosphate core and facilitate it to penetrate the blood-brain barrier, thus targeting the glioblastoma cells in a macropinocytosis-dependent manner. The nanostructure carrying ATF5 siRNA exerts remarkable RNA-interfering efficiency, increases glioblastoma cell apoptosis and inhibits tumour cell growth both in vitro and in xenograft tumour models. This strategy of targeting the macropinocytosis caused by Ras activation provides a nanoparticle-based approach for precision therapy in glioblastoma and other Ras-activated cancers.

MARK1 is a Novel Target for miR-125a-5p: Implications for Cell Migration in Cervical Tumor Cells.

PubMed

Natalia, Martinez-Acuna; Alejandro, Gonzalez-Torres; Virginia, Tapia-Vieyra Juana; Alvarez-Salas, Luis Marat

2018-01-01

Aberrant miRNA expression is associated with the development of several diseases including cervical cancer. Dysregulation of miR-125a-5p is present in a plethora of tumors, but its role in cervical cancer is not well understood. The aim was to analyze the expression profile of miR-125a-5p in tumor and immortal cell lines with further target prediction, validation and function analysis. MiR-125a-5p expression was determined by real-time RT-PCR from nine cervical cell lines. In silico tools were used to find target transcripts with an miR-125-5p complementary site within the 3'UTR region. Further target selection was based on gene ontology annotation and ΔG analysis. Target validation was performed by transfection of synthetic miR-125a-5p mimics and luciferase assays. Functional evaluation of miR-125a-5p on migration was performed by transwell migration assays. Differential miR-125a-5p expression was observed between immortal and tumor cells regardless of the human papillomavirus (HPV) content. Thermodynamic and ontological analyses showed Microtubule-Affinity-Regulating Kinase1 (MARK1) as a putative target for miR-125a-5p. An inverse correlation was observed among miR-125a-5p expression and MARK1 protein levels in tumor but not in immortal cells. Luciferase assays showed direct miR-125a-5p regulation over MARK1 through recognition of a predicted target site within the 3'-UTR. HeLa and C-33A cervical tumor cells enhanced migration after transfection with miR-125a-5p mimics and stimulation of cell migration was reproduced by siRNA-mediated inhibition of MARK1. The results showed MARK1 as a novel functional target for miR-125a-5p with implications on cell migration of tumor cervical cancer cells. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Ion mediated targeting of cells with nanoparticles

NASA Astrophysics Data System (ADS)

Maheshwari, Vivek; Fu, Jinlong

2010-03-01

In eukaryotic cells, Ca^2+ ions are necessary for intracellular signaling, in activity of mitochondria and a variety of other cellular process that have been linked to cell apoptosis, proteins synthesis and cell-cycle regulation. Here we show that Ca^2+ ions, serving as the bio-compatible interface can be used to target Saccharomyces cerevisiae (SaC, baker's yeast), a model eukaryotic cell, with Au nanoparticles (10 nm). The Ca^2+ ions bind to the carboxylic acid groups in the citrate functionalized Au nanoparticles. This transforms the nanoparticles into micron long 1-D branched chain assemblies due to inter-particle dipole-dipole interaction and inter-particle bonding due to the divalent nature of the Ca^2+ ion. A similar transformation is observed with the use of divalent ions Mg^2+, Cd^2+ and Fe^2+. The 1-D assembly aids the interfacing of ion-nanoparticles on the cell by providing multiple contact points. Further monovalent ions such as Na^+ are also effective for the targeting of the cell with nanoparticles. However Na-Au nanoparticles are limited in their deposition as they exist in solution as single particles. The cells remain alive after the deposition process and their vitality is unaffected by the interfacing with ion-nanoparticles.

T-REX on-demand redox targeting in live cells.

PubMed

Parvez, Saba; Long, Marcus J C; Lin, Hong-Yu; Zhao, Yi; Haegele, Joseph A; Pham, Vanha N; Lee, Dustin K; Aye, Yimon

2016-12-01

This protocol describes targetable reactive electrophiles and oxidants (T-REX)-a live-cell-based tool designed to (i) interrogate the consequences of specific and time-resolved redox events, and (ii) screen for bona fide redox-sensor targets. A small-molecule toolset comprising photocaged precursors to specific reactive redox signals is constructed such that these inert precursors specifically and irreversibly tag any HaloTag-fused protein of interest (POI) in mammalian and Escherichia coli cells. Syntheses of the alkyne-functionalized endogenous reactive signal 4-hydroxynonenal (HNE(alkyne)) and the HaloTag-targetable photocaged precursor to HNE(alkyne) (also known as Ht-PreHNE or HtPHA) are described. Low-energy light prompts photo-uncaging (t 1/2 <1-2 min) and target-specific modification. The targeted modification of the POI enables precisely timed and spatially controlled redox events with no off-target modification. Two independent pathways are described, along with a simple setup to functionally validate known targets or discover novel sensors. T-REX sidesteps mixed responses caused by uncontrolled whole-cell swamping with reactive signals. Modification and downstream response can be analyzed by in-gel fluorescence, proteomics, qRT-PCR, immunofluorescence, fluorescence resonance energy transfer (FRET)-based and dual-luciferase reporters, or flow cytometry assays. T-REX targeting takes 4 h from initial probe treatment. Analysis of targeted redox responses takes an additional 4-24 h, depending on the nature of the pathway and the type of readouts used.

T-REX on-demand redox targeting in live cells

PubMed Central

Parvez, Saba; Long, Marcus J C; Lin, Hong-Yu; Zhao, Yi; Haegele, Joseph A; Pham, Vanha N; Lee, Dustin K; Aye, Yimon

2017-01-01

This protocol describes targetable reactive electrophiles and oxidants (T-REX)—a live-cell-based tool designed to (i) interrogate the consequences of specific and time-resolved redox events, and (ii) screen for bona fide redox-sensor targets. A small-molecule toolset comprising photocaged precursors to specific reactive redox signals is constructed such that these inert precursors specifically and irreversibly tag any HaloTag-fused protein of interest (POI) in mammalian and Escherichia coli cells. Syntheses of the alkyne-functionalized endogenous reactive signal 4-hydroxynonenal (HNE (alkyne)) and the HaloTag-targetable photocaged precursor to HNE (alkyne) (also known as Ht-PreHNE or HtPHA) are described. Low-energy light prompts photo-uncaging (t1/2 <1–2 min) and target-specific modification. The targeted modification of the POI enables precisely timed and spatially controlled redox events with no off-target modification. Two independent pathways are described, along with a simple setup to functionally validate known targets or discover novel sensors. T-REX sidesteps mixed responses caused by uncontrolled whole-cell swamping with reactive signals. Modification and downstream response can be analyzed by in-gel fluorescence, proteomics, qRT-PCR, immunofluorescence, fluorescence resonance energy transfer (FRET)-based and dual-luciferase reporters, or flow cytometry assays. T-REX targeting takes 4 h from initial probe treatment. Analysis of targeted redox responses takes an additional 4–24 h, depending on the nature of the pathway and the type of readouts used. PMID:27809314

Combustion-derived ultrafine particles transport organic toxicants to target respiratory cells.

PubMed

Penn, Arthur; Murphy, Gleeson; Barker, Steven; Henk, William; Penn, Lynn

2005-08-01

Epidemiologic evidence supports associations between inhalation of fine and ultrafine ambient particulate matter [aerodynamic diameter < or = 2.5 microm (PM2.5)] and increases in cardiovascular/respiratory morbidity and mortality. Less attention has been paid to how the physical and chemical characteristics of these particles may influence their interactions with target cells. Butadiene soot (BDS), produced during combustion of the high-volume petrochemical 1,3-butadiene, is rich in polynuclear aromatic hydrocarbons (PAHs), including known carcinogens. We conducted experiments to characterize BDS with respect to particle size distribution, assembly, PAH composition, elemental content, and interaction with respiratory epithelial cells. Freshly generated, intact BDS is primarily (> 90%) PAH-rich, metals-poor (nickel, chromium, and vanadium concentrations all < 1 ppm) PM2.5, composed of uniformly sized, solid spheres (30-50 nm) in aggregated form. Cells of a human bronchial epithelial cell line (BEAS-2B) exhibit sequential fluorescent responses--a relatively rapid (approximately 30 min), bright but diffuse fluorescence followed by the slower (2-4 hr) appearance of punctate cytoplasmic fluorescence--after BDS is added to medium overlying the cells. The fluorescence is associated with PAH localization in the cells. The ultrafine BDS particles move down through the medium to the cell membrane. Fluorescent PAHs are transferred from the particle surface to the cell membrane, cross the membrane into the cytosol, and appear to accumulate in lipid vesicles. There is no evidence that BDS particles pass into the cells. The results demonstrate that uptake of airborne ultrafine particles by target cells is not necessary for transfer of toxicants from the particles to the cells.

Diffusion tensor driven contour closing for cell microinjection targeting.

PubMed

Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

2010-01-01

This article introduces a novel approach to robust automatic detection of unstained living cells in bright-field (BF) microscope images with the goal of producing a target list for an automated microinjection system. The overall image analysis process is described and includes: preprocessing, ridge enhancement, image segmentation, shape analysis and injection point definition. The developed algorithm implements a new version of anisotropic contour completion (ACC) based on the partial differential equation (PDE) for heat diffusion which improves the cell segmentation process by elongating the edges only along their tangent direction. The developed ACC algorithm is equivalent to a dilation of the binary edge image with a continuous elliptic structural element that takes into account local orientation of the contours preventing extension towards normal direction. Experiments carried out on real images of 10 to 50 microm CHO-K1 adherent cells show a remarkable reliability in the algorithm along with up to 85% success for cell detection and injection point definition.

Driver genes in non-small cell lung cancer: Characteristics, detection methods, and targeted therapies

PubMed Central

He, Bing; Zhang, Hu-Qin

2017-01-01

Lung cancer is one of the most common causes of cancer-related death in the world. The large number of lung cancer cases is non-small cell lung cancer (NSCLC), which approximately accounting for 75% of lung cancer. Over the past years, our comprehensive knowledge about the molecular biology of NSCLC has been rapidly enriching, which has promoted the discovery of driver genes in NSCLC and directed FDA-approved targeted therapies. Of course, the targeted therapies based on driver genes provide a more exact option for advanced non-small cell lung cancer, improving the survival rate of patients. Now, we will review the landscape of driver genes in NSCLC including the characteristics, detection methods, the application of target therapy and challenges. PMID:28915704

Landscape phages and their fusion proteins targeted to breast cancer cells

PubMed Central

Fagbohun, Olusegun A.; Bedi, Deepa; Grabchenko, Natalia I.; Deinnocentes, Patricia A.; Bird, Richard C.; Petrenko, Valery A.

2012-01-01

Breast cancer is a leading cause of death among women in the USA. The efficacy of existing anticancer therapeutics can be improved by targeting them through conjugation with ligands binding to cellular receptors. Recently, we developed a novel drug targeting strategy based on the use of pre-selected cancer-specific ‘fusion pVIII proteins’ (fpVIII), as targeting ligands. To study the efficiency of this approach in animal models, we developed a panel of breast cancer cell-binding phages as a source of targeted fpVIIIs. Two landscape phage peptide libraries (8-mer f8/8 and 9-mer f8/9) were screened to isolate 132 phage variants that recognize breast carcinoma cells MCF-7 and ZR-75-1 and internalize into the cells. When tested for their interaction with the breast cancer cells in comparison with liver cancer cells HepG2, human mammary cells MCF-10A cells and serum, 16 of the phage probes selectively interacted with the breast cancer cells whereas 32 bound both breast and liver cancer cells. The most prominent cancer-specific phage DMPGTVLP, demonstrating sub-nanomolar Kd in interaction with target cells, was used for affinity chromatography of cellular membrane molecules to reveal its potential binding receptor. The isolated protein was identified by direct sequencing as cellular surface nucleolin. This conclusion was confirmed by inhibition of the phage–cell interaction with nucleolin antibodies. Other prominent phage binders VPTDTDYS, VEEGGYIAA, and DWRGDSMDS demonstrate consensus motifs common to previously identified cancer-specific peptides. Isolated phage proteins exhibit inherent binding specificity towards cancer cells, demonstrating the functional activity of the selected fused peptides. The selected phages, their peptide inserts and intact fusion proteins can serve as promising ligands for the development of targeted nanomedicines and their study in model mice with xenograft of human cells MCF-7 and ZR-75-1. PMID:22490956

Premature activation of the paramyxovirus fusion protein before target cell attachment with corruption of the viral fusion machinery.

PubMed

Farzan, Shohreh F; Palermo, Laura M; Yokoyama, Christine C; Orefice, Gianmarco; Fornabaio, Micaela; Sarkar, Aurijit; Kellogg, Glen E; Greengard, Olga; Porotto, Matteo; Moscona, Anne

2011-11-04

Paramyxoviruses, including the childhood pathogen human parainfluenza virus type 3, enter host cells by fusion of the viral and target cell membranes. This fusion results from the concerted action of its two envelope glycoproteins, the hemagglutinin-neuraminidase (HN) and the fusion protein (F). The receptor-bound HN triggers F to undergo conformational changes that render it competent to mediate fusion of the viral and cellular membranes. We proposed that, if the fusion process could be activated prematurely before the virion reaches the target host cell, infection could be prevented. We identified a small molecule that inhibits paramyxovirus entry into target cells and prevents infection. We show here that this compound works by an interaction with HN that results in F-activation prior to receptor binding. The fusion process is thereby prematurely activated, preventing fusion of the viral membrane with target cells and precluding viral entry. This first evidence that activation of a paramyxovirus F can be specifically induced before the virus contacts its target cell suggests a new strategy with broad implications for the design of antiviral agents.

Modular cell-internalizing aptamer nanostructure enables targeted delivery of large functional RNAs in cancer cell lines.

PubMed

Porciani, David; Cardwell, Leah N; Tawiah, Kwaku D; Alam, Khalid K; Lange, Margaret J; Daniels, Mark A; Burke, Donald H

2018-06-11

Large RNAs and ribonucleoprotein complexes have powerful therapeutic potential, but effective cell-targeted delivery tools are limited. Aptamers that internalize into target cells can deliver siRNAs (<15 kDa, 19-21 nt/strand). We demonstrate a modular nanostructure for cellular delivery of large, functional RNA payloads (50-80 kDa, 175-250 nt) by aptamers that recognize multiple human B cell cancer lines and transferrin receptor-expressing cells. Fluorogenic RNA reporter payloads enable accelerated testing of platform designs and rapid evaluation of assembly and internalization. Modularity is demonstrated by swapping in different targeting and payload aptamers. Both modules internalize into leukemic B cell lines and remained colocalized within endosomes. Fluorescence from internalized RNA persists for ≥2 h, suggesting a sizable window for aptamer payloads to exert influence upon targeted cells. This demonstration of aptamer-mediated, cell-internalizing delivery of large RNAs with retention of functional structure raises the possibility of manipulating endosomes and cells by delivering large aptamers and regulatory RNAs.

Targeting brain metastases in ALK-rearranged non-small-cell lung cancer.

PubMed

Zhang, Isabella; Zaorsky, Nicholas G; Palmer, Joshua D; Mehra, Ranee; Lu, Bo

2015-10-01

The incidence of brain metastases has increased as a result of improved systemic control and advances in imaging. However, development of novel therapeutics with CNS activity has not advanced at the same rate. Research on molecular markers has revealed many potential targets for antineoplastic agents, and a particularly important aberration is translocation in the ALK gene, identified in non-small-cell lung cancer (NSCLC). ALK inhibitors have shown systemic efficacy against ALK-rearranged NSCLC in many clinical trials, but the effectiveness of crizotinib in CNS disease is limited by poor blood-brain barrier penetration and acquired drug resistance. In this Review, we discuss potential pathways to target ALK-rearranged brain metastases, including next generation ALK inhibitors with greater CNS penetration and mechanisms to overcome resistance. Other important mechanisms to control CNS disease include targeting pathways downstream of ALK phosphorylation, increasing the permeability of the blood-brain barrier, modifying the tumour microenvironment, and adding concurrent radiotherapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Novel strategies targeting cancer stem cells through phytochemicals and their analogs

PubMed Central

Dandawate, Prasad; Padhye, Subhash; Ahmad, Aamir

2013-01-01

Cancer stem cells (CSCs) are cells that exist within a tumor with a capacity of self-renewal and an ability to differentiate, giving rise to heterogeneous populations of cancer cells. These cells are increasingly being implicated in resistance to conventional therapeutics and have also been implicated in tumor recurrence. Several cellular signaling pathways including Notch, Wnt, phosphoinositide-3-kinase–Akt–mammalian target of rapamycin pathways, and known markers such as CD44, CD133, CD166, ALDH, etc. have been associated with CSCs. Here, we have reviewed our current understanding of self-renewal pathways and factors that help in the survival of CSCs with special emphasis on those that have been documented to be modulated by well characterized natural agents such as curcumin, sulforaphane, resveratrol, genistein, and epigallocatechin gallate. With the inclusion of a novel derivative of curcumin, CDF, we showcase how natural agents can be effectively modified to increase their efficacy, particularly against CSCs. We hope that this article will generate interest among researchers for further mechanistic and clinical studies exploiting the cancer preventive and therapeutic role of nutraceuticals by targeted elimination of CSCs. PMID:24076568

The cancer cell adhesion resistome: mechanisms, targeting and translational approaches.

PubMed

Dickreuter, Ellen; Cordes, Nils

2017-06-27

Cell adhesion-mediated resistance limits the success of cancer therapies and is a great obstacle to overcome in the clinic. Since the 1990s, where it became clear that adhesion of tumor cells to the extracellular matrix is an important mediator of therapy resistance, a lot of work has been conducted to understand the fundamental underlying mechanisms and two paradigms were deduced: cell adhesion-mediated radioresistance (CAM-RR) and cell adhesion-mediated drug resistance (CAM-DR). Preclinical work has evidently demonstrated that targeting of integrins, adapter proteins and associated kinases comprising the cell adhesion resistome is a promising strategy to sensitize cancer cells to both radiotherapy and chemotherapy. Moreover, the cell adhesion resistome fundamentally contributes to adaptation mechanisms induced by radiochemotherapy as well as molecular drugs to secure a balanced homeostasis of cancer cells for survival and growth. Intriguingly, this phenomenon provides a basis for synthetic lethal targeted therapies simultaneously administered to standard radiochemotherapy. In this review, we summarize current knowledge about the cell adhesion resistome and highlight targeting strategies to override CAM-RR and CAM-DR.

Application of stem cells in targeted therapy of breast cancer: a systematic review.

PubMed

Madjd, Zahra; Gheytanchi, Elmira; Erfani, Elham; Asadi-Lari, Mohsen

2013-01-01

The aim of this systematic review was to investigate whether stem cells could be effectively applied in targeted therapy of breast cancer. A systematic literature search was performed for original articles published from January 2007 until May 2012. Nine studies met the inclusion criteria for phase I or II clinical trials, of which three used stem cells as vehicles, two trials used autologous hematopoetic stem cells and in four trials cancer stem cells were targeted. Mesenchymal stem cells (MSCs) were applied as cellular vehicles to transfer therapeutic agents. Cell therapy with MSC can successfully target resistant cancers. Cancer stem cells were selectively targeted via a proteasome-dependent suicide gene leading to tumor regression. Wnt/β-catenin signaling pathway has been also evidenced to be an attractive CSC-target. This systematic review focused on two different concepts of stem cells and breast cancer marking a turning point in the trials that applied stem cells as cellular vehicles for targeted delivery therapy as well as CSC-targeted therapies. Applying stem cells as targeted therapy could be an effective therapeutic approach for treatment of breast cancer in the clinic and in therapeutic marketing; however this needs to be confirmed with further clinical investigations.

An integrated molecular analysis of lung adenocarcinomas identifies potential therapeutic targets among TTF1-negative tumors including DNA repair proteins and Nrf2

PubMed Central

Cardnell, Robert J.G.; Behrens, Carmen; Diao, Lixia; Fan, YouHong; Tang, Ximing; Tong, Pan; John D., Minna; Mills, Gordon B.; Heymach, John V.; Wistuba, Ignacio I.; Wang, Jing; Byers., Lauren A.

2015-01-01

Purpose Thyroid transcription factor-1 (TTF1) immunohistochemistry (IHC) is used clinically to differentiate primary lung adenocarcinomas (LUAD) from squamous lung cancers and metastatic adenocarcinomas from other primary sites. However, a subset of LUAD (15-20%) does not express TTF1 and TTF1-negative patients have worse clinical outcomes. As there are no established targeted agents with activity in TTF1-negative LUAD, we performed an integrated molecular analysis to identify potential therapeutic targets. Experimental Design Using two clinical LUAD cohorts (274 tumors), one from our institution (PROSPECT) and the TCGA, we interrogated proteomic profiles (by reverse-phase protein array (RPPA)), gene expression, and mutational data. Drug response data from 74 cell lines were used to validate potential therapeutic agents. Results Strong correlations were observed between TTF1 IHC and TTF1 measurements by RPPA (Rho=0.57, p<0.001) and gene expression (NKX2-1, Rho=0.61, p<0.001). Established driver mutations (e.g. BRAF and EGFR) were associated with high TTF1 expression. In contrast, TTF1-negative LUAD had a higher frequency of inactivating KEAP1 mutations (p=0.001). Proteomic profiling identified increased expression of DNA repair proteins (e.g., Chk1 and the DNA repair score) and suppressed PI3K/MAPK signaling among TTF1-negative tumors, with differences in total proteins confirmed at the mRNA level. Cell line analysis showed drugs targeting DNA repair to be more active in TTF1-low cell lines. Conclusions Combined genomic and proteomic analyses demonstrated infrequent alteration of validated lung cancer targets (including the absence of BRAF mutations in TTF1-negative LUAD), but identified novel potential targets for TTF1-negative LUAD includingKEAP1/Nrf2 and DNA repair pathways. PMID:25878335

Epidermal Growth Factor Receptor Tyrosine Kinase: A Potential Target in Treatment of Non-Small-Cell Lung Carcinoma.

PubMed

Prabhu, Venugopal Vinod; Devaraj, Niranjali

2017-01-01

Lung cancer is responsible for 1.6 million deaths. Approximately 80%-85% of lung cancers are of the non-small-cell variety, which includes squamous cell carcinoma, adenocarcinoma, and large-cell carcinoma. Knowing the stage of cancer progression is a requisite for determining which management approach-surgery, chemotherapy, radiotherapy, and/or immunotherapy-is optimal. Targeted therapeutic approaches with antiangiogenic monoclonal antibodies or tyrosine kinase inhibitors are one option if tumors harbor oncogene mutations. Another, newer approach is directed against cancer-specific molecules and signaling pathways and thus has more limited nonspecific toxicities. This approach targets the epidermal growth factor receptor (EGFR, HER-1/ErbB1), a receptor tyrosine kinase of the ErbB family, which consists of four closely related receptors: HER-1/ErbB1, HER-2/neu/ErbB2, HER-3/ErbB3, and HER-4/ErbB4. Because EGFR is expressed at high levels on the surface of some cancer cells, it has been recognized as an effective anticancer target. EGFR-targeted therapies include monoclonal antibodies (mAbs) and small-molecule tyrosine kinase inhibitors. Tyrosine kinases are an especially important target because they play an important role in the modulation of growth factor signaling. This review highlights various classes of synthetically derived molecules that have been reported in the last few years as potential EGFR-TK inhibitors (TKIs) and their targeted therapies in NSCLC, along with effective strategies for overcoming EGFR-TKI resistance and efforts to develop a novel potent EGFR-TKI as an efficient target of NSCLC treatment in the foreseeable future.

Highly sensitive and specific colorimetric detection of cancer cells via dual-aptamer target binding strategy.

PubMed

Wang, Kun; Fan, Daoqing; Liu, Yaqing; Wang, Erkang

2015-11-15

Simple, rapid, sensitive and specific detection of cancer cells is of great importance for early and accurate cancer diagnostics and therapy. By coupling nanotechnology and dual-aptamer target binding strategies, we developed a colorimetric assay for visually detecting cancer cells with high sensitivity and specificity. The nanotechnology including high catalytic activity of PtAuNP and magnetic separation & concentration plays a vital role on the signal amplification and improvement of detection sensitivity. The color change caused by small amount of target cancer cells (10 cells/mL) can be clearly distinguished by naked eyes. The dual-aptamer target binding strategy guarantees the detection specificity that large amount of non-cancer cells and different cancer cells (10(4) cells/mL) cannot cause obvious color change. A detection limit as low as 10 cells/mL with detection linear range from 10 to 10(5) cells/mL was reached according to the experimental detections in phosphate buffer solution as well as serum sample. The developed enzyme-free and cost effective colorimetric assay is simple and no need of instrument while still provides excellent sensitivity, specificity and repeatability, having potential application on point-of-care cancer diagnosis. Copyright © 2015 Elsevier B.V. All rights reserved.

New targeted therapies for indolent B-cell malignancies in older patients.

PubMed

Krem, Maxwell M; Gopal, Ajay K

2015-01-01

Molecularly targeted agents have become an established component of the treatment of indolent B-cell malignancies (iNHL). iNHL disproportionately affects older adults, so treatments that have excellent tolerability and efficacy across multiple lines of therapy are in demand. The numbers and classes of targeted therapies for iNHL have proliferated rapidly in recent years; classes of agents that show promise for older patients with iNHL include anti-CD20 antibodies, phosphatidyl-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway inhibitors, immunomodulators, proteasome inhibitors, epigenetic modulators, and immunotherapies. Here, we review the proposed mechanisms of action, efficacy, and tolerability of novel agents for iNHL, with an emphasis on their applicability to older patients.

Prodrug Strategy for PSMA-targeted Delivery of TGX-221 to Prostate Cancer Cells

PubMed Central

Zhao, Yunqi; Duan, Shaofeng; Zeng, Xing; Liu, Chunjing; Davies, Neal M.; Li, Benyi; Forrest, M. Laird

2013-01-01

TGX-221 is a potent, selective, and cell membrane permeable inhibitor of the PI3K p110β catalytic subunit. Recent studies showed that TGX-221 has anti-proliferative activity against PTEN-deficient tumor cell lines including prostate cancers. The objective of this study was to develop an encapsulation system for parenterally delivering TGX-221 to the target tissue through a prostate-specific membrane aptamer (PSMAa10) with little or no side effects. In this study, PEG-PCL micelles were formulated to encapsulate the drug, and a prodrug strategy was pursued to improve the stability of the carrier system. Fluorescence imaging studies demonstrated that the cellular uptake of both drug and nanoparticles were significantly improved by targeted micelles in a PSMA positive cell line. The area under the plasma concentration time curve of the micelle formulation in nude mice was 2.27-fold greater than the naked drug, and the drug clearance rate was 17.5-fold slower. These findings suggest a novel formulation approach for improving site-specific drug delivery of a molecular-targeted prostate cancer treatment. PMID:22494444

Concise Review: Emerging Drugs Targeting Epithelial Cancer Stem-Like Cells.

PubMed

Ahmed, Mehreen; Chaudhari, Kritika; Babaei-Jadidi, Roya; Dekker, Lodewijk V; Shams Nateri, Abdolrahman

2017-04-01

Increasing evidence suggests that cancer cell populations contain a small proportion of cells that display stem-like cell properties and which may be responsible for overall tumor maintenance. These cancer stem-like cells (CSCs) appear to have unique tumor-initiating ability and innate survival mechanisms that allow them to resist cancer therapies, consequently promoting relapses. Selective targeting of CSCs may provide therapeutic benefit and several recent reports have indicated this may be possible. In this article, we review drugs targeting CSCs, in selected epithelial cell-derived cancers. Stem Cells 2017;35:839-850. © 2017 AlphaMed Press.

Structural Features Facilitating Tumor Cell Targeting and Internalization by Bleomycin and Its Disaccharide

PubMed Central

2016-01-01

We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide–cytotoxin conjugates. PMID:25905565

MicroRNA-944 Affects Cell Growth by Targeting EPHA7 in Non-Small Cell Lung Cancer.

PubMed

Liu, Minxia; Zhou, Kecheng; Cao, Yi

2016-09-26

MicroRNAs (miRNAs) have critical roles in lung tumorigenesis and development. To determine aberrantly expressed miRNAs involved in non-small cell lung cancer (NSCLC) and investigate pathophysiological functions and mechanisms, we firstly carried out small RNA deep sequencing in NSCLC cell lines (EPLC-32M1, A549 and 801D) and a human immortalized cell line 16HBE, we then studied miRNA function by cell proliferation and apoptosis. cDNA microarray, luciferase reporter assay and miRNA transfection were used to investigate interaction between the miRNA and target gene. miR-944 was significantly down-regulated in NSCLC and had many putative targets. Moreover, the forced expression of miR-944 significantly inhibited the proliferation of NSCLC cells in vitro. By integrating mRNA expression data and miR-944-target prediction, we disclosed that EPHA7 was a potential target of miR-944, which was further verified by luciferase reporter assay and microRNA transfection. Our data indicated that miR-944 targets EPHA7 in NSCLC and regulates NSCLC cell proliferation, which may offer a new mechanism underlying the development and progression of NSCLC.

Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

NASA Astrophysics Data System (ADS)

Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm; Iversen, Frank; Liu, Zhuo; Thomsen, Karen; Pedersen, Michael; Skrydstrup, Troels; Nielsen, Niels Chr.; Ploug, Michael; Kjems, Jørgen

2013-08-01

Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific

New Strategies in Engineering T-cell Receptor Gene-Modified T cells to More Effectively Target Malignancies.

PubMed

Schmitt, Thomas M; Stromnes, Ingunn M; Chapuis, Aude G; Greenberg, Philip D

2015-12-01

The immune system, T cells in particular, have the ability to target and destroy malignant cells. However, antitumor immune responses induced from the endogenous T-cell repertoire are often insufficient for the eradication of established tumors, as illustrated by the failure of cancer vaccination strategies or checkpoint blockade for most tumors. Genetic modification of T cells to express a defined T-cell receptor (TCR) can provide the means to rapidly generate large numbers of tumor-reactive T cells capable of targeting tumor cells in vivo. However, cell-intrinsic factors as well as immunosuppressive factors in the tumor microenvironment can limit the function of such gene-modified T cells. New strategies currently being developed are refining and enhancing this approach, resulting in cellular therapies that more effectively target tumors and that are less susceptible to tumor immune evasion. ©2015 American Association for Cancer Research.

Stages of Plasma Cell Neoplasms (Including Multiple Myeloma)

MedlinePlus

... Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key Points ...

Molecular characterization of oral squamous cell carcinoma using targeted next-generation sequencing.

PubMed

Er, Tze-Kiong; Wang, Yen-Yun; Chen, Chih-Chieh; Herreros-Villanueva, Marta; Liu, Ta-Chih; Yuan, Shyng-Shiou F

2015-10-01

Many genetic factors play an important role in the development of oral squamous cell carcinoma. The aim of this study was to assess the mutational profile in oral squamous cell carcinoma using formalin-fixed, paraffin-embedded tumors from a Taiwanese population by performing targeted sequencing of 26 cancer-associated genes that are frequently mutated in solid tumors. Next-generation sequencing was performed in 50 formalin-fixed, paraffin-embedded tumor specimens obtained from patients with oral squamous cell carcinoma. Genetic alterations in the 26 cancer-associated genes were detected using a deep sequencing (>1000X) approach. TP53, PIK3CA, MET, APC, CDH1, and FBXW7 were most frequently mutated genes. Most remarkably, TP53 mutations and PIK3CA mutations, which accounted for 68% and 18% of tumors, respectively, were more prevalent in a Taiwanese population. Other genes including MET (4%), APC (4%), CDH1 (2%), and FBXW7 (2%) were identified in our population. In summary, our study shows the feasibility of performing targeted sequencing using formalin-fixed, paraffin-embedded samples. Additionally, this study also reports the mutational landscape of oral squamous cell carcinoma in the Taiwanese population. We believe that this study will shed new light on fundamental aspects in understanding the molecular pathogenesis of oral squamous cell carcinoma and may aid in the development of new targeted therapies. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

MicroRNA-196b Inhibits Cell Growth and Metastasis of Lung Cancer Cells by Targeting Runx2.

PubMed

Bai, Xiaoxue; Meng, Lin; Sun, Huijie; Li, Zhuo; Zhang, Xiufang; Hua, Shucheng

2017-01-01

Lung cancer is one of the most common causes of cancer related deaths worldwide. The role of several microRNAs (miRNAs) including miR-196b in different cancers has already been established. The study was aimed to explore the role of miR-196b in lung cancer and its possible underlying mechanism. Human lung cancer cell line A549 was transfected with miR-196b mimic, miR-196b inhibitor and corresponding controls. Then cell viability, migration, invasion, and apoptosis of A549 lung cancer cells either with overexpression or with suppression of miR-196b were estimated sequentially. Next, dual luciferase activity assay was performed to clarify whether Runx2 was a direct target of miR-196b. Finally, the expressions of main factors associated with epithelial mesenchymal transition (EMT), PI3K/AKT/GSK3β, Smad, and JNK pathways were detected by western blot. MiR-196b expression was significantly decreased in A549, H1650 and H1299 cell lines compared with in WI-38 and HEL-1 cell lines. Overexpression of miR-196b suppressed cell viability, migration, invasion, and induced apoptosis as well as inhibited TGF-β induced EMT process in A549 cells. In addition, Runx2 was a putative target of miR-196b, and Runx2 silence remarkably increased cell apoptosis and abolished the promotive effects of miR-196b suppression on cell viability, migration and invasion. Finally, miR-196b also mediated its action by inactivation of PI3K/AKT/GSK3β, Smad, and JNK pathways by down-regulation of Runx2. MiR-196b functions as a tumor suppressor that inhibited cell growth and metastasis of lung cancer cells by targeting Runx2. These findings provided further evidences for treatment of lung cancer. The Author(s). Published by S. Karger AG, Basel.

New generation of oral mucosal vaccines targeting dendritic cells

PubMed Central

Owen, Jennifer L.; Sahay, Bikash; Mohamadzadeh, Mansour

2013-01-01

As most infectious organisms gain entry at mucosal surfaces, there is a great deal of interest in developing vaccines that elicit effective mucosal immune responses against pathogen challenge. Targeted vaccination is one of the most effective methods available to prevent and control infectious diseases. Mucosal vaccines can offer lower costs, better accessibility, needle free delivery, and a higher capacity for mass immunizations during pandemics. Both local mucosal immunity and robust systemic responses can be achieved through mucosal vaccination. Recent progress in understanding the molecular and cellular components of the mucosal immune system have allowed for the development of a novel mucosal vaccine platform utilizing specific dendritic cell-targeting peptides and orally administered lactobacilli to elicit efficient antigen specific immune responses against infections, including B. anthracis in experimental models of disease. PMID:23835515

Tumor-targeting domains for chimeric antigen receptor T cells.

PubMed

Bezverbnaya, Ksenia; Mathews, Ashish; Sidhu, Jesse; Helsen, Christopher W; Bramson, Jonathan L

2017-01-01

Immunotherapy with chimeric antigen receptor (CAR) T cells has been advancing steadily in clinical trials. Since the ability of engineered T cells to recognize intended tumor-associated targets is crucial for the therapeutic success, antigen-binding domains play an important role in shaping T-cell responses. Single-chain antibody and T-cell receptor fragments, natural ligands, repeat proteins, combinations of the above and universal tag-specific domains have all been used in the antigen-binding moiety of chimeric receptors. Here we outline the advantages and disadvantages of different domains, discuss the concepts of affinity and specificity, and highlight the recent progress of each targeting strategy.

New approach of delivering cytotoxic drugs towards CAIX expressing cells: A concept of dual-target drugs.

PubMed

van Kuijk, Simon J A; Parvathaneni, Nanda Kumar; Niemans, Raymon; van Gisbergen, Marike W; Carta, Fabrizio; Vullo, Daniela; Pastorekova, Silvia; Yaromina, Ala; Supuran, Claudiu T; Dubois, Ludwig J; Winum, Jean-Yves; Lambin, Philippe

2017-02-15

Carbonic anhydrase IX (CAIX) is a hypoxia-regulated and tumor-specific protein that maintains the pH balance of cells. Targeting CAIX might be a valuable approach for specific delivery of cytotoxic drugs, thereby reducing normal tissue side-effects. A series of dual-target compounds were designed and synthesized incorporating a sulfonamide, sulfamide, or sulfamate moiety combined with several different anti-cancer drugs, including the chemotherapeutic agents chlorambucil, tirapazamine, and temozolomide, two Ataxia Telangiectasia and Rad3-related protein inhibitors (ATRi), and the anti-diabetic biguanide agent phenformin. An ATRi derivative (12) was the only compound to show a preferred efficacy in CAIX overexpressing cells versus cells without CAIX expression when combined with radiation. Its efficacy might however not solely depend on binding to CAIX, since all described compounds generally display low activity as carbonic anhydrase inhibitors. The hypothesis that dual-target compounds specifically target CAIX expressing tumor cells was therefore not confirmed. Even though dual-target compounds remain an interesting approach, alternative options should also be investigated as novel treatment strategies. Copyright © 2016 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

Nanomedicine strategies for sustained, controlled, and targeted treatment of cancer stem cells of the digestive system.

PubMed

Xie, Fang-Yuan; Xu, Wei-Heng; Yin, Chuan; Zhang, Guo-Qing; Zhong, Yan-Qiang; Gao, Jie

2016-10-15

Cancer stem cells (CSCs) constitute a small proportion of the cancer cells that have self-renewal capacity and tumor-initiating ability. They have been identified in a variety of tumors, including tumors of the digestive system. CSCs exhibit some unique characteristics, which are responsible for cancer metastasis and recurrence. Consequently, the development of effective therapeutic strategies against CSCs plays a key role in increasing the efficacy of cancer therapy. Several potential approaches to target CSCs of the digestive system have been explored, including targeting CSC surface markers and signaling pathways, inducing the differentiation of CSCs, altering the tumor microenvironment or niche, and inhibiting ATP-driven efflux transporters. However, conventional therapies may not successfully eradicate CSCs owing to various problems, including poor solubility, stability, rapid clearance, poor cellular uptake, and unacceptable cytotoxicity. Nanomedicine strategies, which include drug, gene, targeted, and combinational delivery, could solve these problems and significantly improve the therapeutic index. This review briefly summarizes the ongoing development of strategies and nanomedicine-based therapies against CSCs of the digestive system.

Nanomedicine strategies for sustained, controlled, and targeted treatment of cancer stem cells of the digestive system

PubMed Central

Xie, Fang-Yuan; Xu, Wei-Heng; Yin, Chuan; Zhang, Guo-Qing; Zhong, Yan-Qiang; Gao, Jie

2016-01-01

Cancer stem cells (CSCs) constitute a small proportion of the cancer cells that have self-renewal capacity and tumor-initiating ability. They have been identified in a variety of tumors, including tumors of the digestive system. CSCs exhibit some unique characteristics, which are responsible for cancer metastasis and recurrence. Consequently, the development of effective therapeutic strategies against CSCs plays a key role in increasing the efficacy of cancer therapy. Several potential approaches to target CSCs of the digestive system have been explored, including targeting CSC surface markers and signaling pathways, inducing the differentiation of CSCs, altering the tumor microenvironment or niche, and inhibiting ATP-driven efflux transporters. However, conventional therapies may not successfully eradicate CSCs owing to various problems, including poor solubility, stability, rapid clearance, poor cellular uptake, and unacceptable cytotoxicity. Nanomedicine strategies, which include drug, gene, targeted, and combinational delivery, could solve these problems and significantly improve the therapeutic index. This review briefly summarizes the ongoing development of strategies and nanomedicine-based therapies against CSCs of the digestive system. PMID:27795813

Prediction of intracellular exposure bridges the gap between target- and cell-based drug discovery

PubMed Central

Gordon, Laurie J.; Wayne, Gareth J.; Almqvist, Helena; Axelsson, Hanna; Seashore-Ludlow, Brinton; Treyer, Andrea; Lundbäck, Thomas; West, Andy; Hann, Michael M.; Artursson, Per

2017-01-01

Inadequate target exposure is a major cause of high attrition in drug discovery. Here, we show that a label-free method for quantifying the intracellular bioavailability (Fic) of drug molecules predicts drug access to intracellular targets and hence, pharmacological effect. We determined Fic in multiple cellular assays and cell types representing different targets from a number of therapeutic areas, including cancer, inflammation, and dementia. Both cytosolic targets and targets localized in subcellular compartments were investigated. Fic gives insights on membrane-permeable compounds in terms of cellular potency and intracellular target engagement, compared with biochemical potency measurements alone. Knowledge of the amount of drug that is locally available to bind intracellular targets provides a powerful tool for compound selection in early drug discovery. PMID:28701380

Optical cell monitoring system for underwater targets

NASA Astrophysics Data System (ADS)

Moon, SangJun; Manzur, Fahim; Manzur, Tariq; Demirci, Utkan

2008-10-01

We demonstrate a cell based detection system that could be used for monitoring an underwater target volume and environment using a microfluidic chip and charge-coupled-device (CCD). This technique allows us to capture specific cells and enumerate these cells on a large area on a microchip. The microfluidic chip and a lens-less imaging platform were then merged to monitor cell populations and morphologies as a system that may find use in distributed sensor networks. The chip, featuring surface chemistry and automatic cell imaging, was fabricated from a cover glass slide, double sided adhesive film and a transparent Polymethlymetacrylate (PMMA) slab. The optically clear chip allows detecting cells with a CCD sensor. These chips were fabricated with a laser cutter without the use of photolithography. We utilized CD4+ cells that are captured on the floor of a microfluidic chip due to the ability to address specific target cells using antibody-antigen binding. Captured CD4+ cells were imaged with a fluorescence microscope to verify the chip specificity and efficiency. We achieved 70.2 +/- 6.5% capturing efficiency and 88.8 +/- 5.4% specificity for CD4+ T lymphocytes (n = 9 devices). Bright field images of the captured cells in the 24 mm × 4 mm × 50 μm microfluidic chip were obtained with the CCD sensor in one second. We achieved an inexpensive system that rapidly captures cells and images them using a lens-less CCD system. This microfluidic device can be modified for use in single cell detection utilizing a cheap light-emitting diode (LED) chip instead of a wide range CCD system.

Efficient Generation of Somatic Cell Nuclear Transfer-Competent Porcine Cells with Mutated Alleles at Multiple Target Loci by Using CRISPR/Cas9 Combined with Targeted Toxin-Based Selection System.

PubMed

Sato, Masahiro; Miyoshi, Kazuchika; Nakamura, Shingo; Ohtsuka, Masato; Sakurai, Takayuki; Watanabe, Satoshi; Kawaguchi, Hiroaki; Tanimoto, Akihide

2017-12-04

The recent advancement in genome editing such a CRISPR/Cas9 system has enabled isolation of cells with knocked multiple alleles through a one-step transfection. Somatic cell nuclear transfer (SCNT) has been frequently employed as one of the efficient tools for the production of genetically modified (GM) animals. To use GM cells as SCNT donor, efficient isolation of transfectants with mutations at multiple target loci is often required. The methods for the isolation of such GM cells largely rely on the use of drug selection-based approach using selectable genes; however, it is often difficult to isolate cells with mutations at multiple target loci. In this study, we used a novel approach for the efficient isolation of porcine cells with at least two target loci mutations by one-step introduction of CRISPR/Cas9-related components. A single guide (sg) RNA targeted to GGTA1 gene, involved in the synthesis of cell-surface α-Gal epitope (known as xenogenic antigen), is always a prerequisite. When the transfected cells were reacted with toxin-labeled BS-I-B₄ isolectin for 2 h at 37 C to eliminate α-Gal epitope-expressing cells, the surviving clones lacked α-Gal epitope expression and were highly expected to exhibit induced mutations at another target loci. Analysis of these α-Gal epitope-negative surviving cells demonstrated a 100% occurrence of genome editing at target loci. SCNT using these cells as donors resulted in the production of cloned blastocysts with the genotype similar to that of the donor cells used. Thus, this novel system will be useful for SCNT-mediated acquisition of GM cloned piglets, in which multiple target loci may be mutated.

Curcumin suppresses proliferation of colon cancer cells by targeting CDK2.

PubMed

Lim, Tae-Gyu; Lee, Sung-Young; Huang, Zunnan; Lim, Do Young; Chen, Hanyong; Jung, Sung Keun; Bode, Ann M; Lee, Ki Won; Dong, Zigang

2014-04-01

Curcumin, the yellow pigment of turmeric found in Southeast Indian food, is one of the most popular phytochemicals for cancer prevention. Numerous reports have demonstrated modulation of multiple cellular signaling pathways by curcumin and its molecular targets in various cancer cell lines. To identify a new molecular target of curcumin, we used shape screening and reverse docking to screen the Protein Data Bank against curcumin. Cyclin-dependent kinase 2 (CDK2), a major cell-cycle protein, was identified as a potential molecular target of curcumin. Indeed, in vitro and ex vivo kinase assay data revealed a dramatic suppressive effect of curcumin on CDK2 kinase activity. Furthermore, curcumin induced G1 cell-cycle arrest, which is regulated by CDK2 in HCT116 cells. Although the expression levels of CDK2 and its regulatory subunit, cyclin E, were not changed, the phosphorylation of retinoblastoma (Rb), a well-known CDK2 substrate, was reduced by curcumin. Because curcumin induced cell-cycle arrest, we investigated the antiproliferative effect of curcumin on HCT116 colon cancer cells. In this experiment, curcumin suppressed HCT116 cell proliferation effectively. To determine whether CDK2 is a direct target of curcumin, CDK2 expression was knocked down in HCT116 cells. As expected, HCT116 sh-CDK2 cells exhibited G1 arrest and reduced proliferation. Because of the low levels of CDK2 in HCT116 sh-CDK2 cells, the effects of curcumin on G1 arrest and cell proliferation were not substantially relative to HCT116 sh-control cells. From these results, we identified CDK2 as a direct target of curcumin in colon cancer cells.

Curcumin suppresses proliferation of colon cancer cells by targeting CDK2

PubMed Central

Lim, Tae-Gyu; Lee, Sung-Young; Huang, Zunnan; Lim, Do Young; Chen, Hanyong; Jung, Sung Keun; Bode, Ann M.; Lee, Ki Won; Dong, Zigang

2014-01-01

Curcumin, the yellow pigment of turmeric found in Southeast Indian food, is one of the most popular phytochemicals for cancer prevention. Numerous reports have demonstrated modulation of multiple cellular signaling pathways by curcumin and its molecular targets in various cancer cell lines. To identify a new molecular target of curcumin, we used shape screening and reverse docking to screen the protein data bank against curcumin. Cyclin dependent kinase 2 (CDK2), a major cell cycle protein, was identified as a potential molecular target of curcumin. Indeed, in vitro and ex vivo kinase assay data revealed a dramatic suppressive effect of curcumin on CDK2 kinase activity. Furthermore, curcumin induced G1 cell cycle arrest, which is regulated by CDK2 in HCT116 cells. Although the expression levels of CDK2 and its regulatory subunit, cyclin E, were not changed, the phosphorylation of Rb, a well-known CDK2 substrate, was reduced by curcumin. Because curcumin induced cell cycle arrest, we investigated the anti-proliferative effect of curcumin on HCT116 colon cancer cells. In this experiment, curcumin suppressed HCT116 cell proliferation effectively. To determine if CDK2 is a direct target of curcumin, CDK2 expression was knocked down in HCT116 cells. As expected, HCT116 sh-CDK2 cells exhibited G1 arrest and reduced proliferation. Because of the low levels of CDK2 in HCT116 sh-CDK2 cells, the effects of curcumin on G1 arrest and cell proliferation were not substantial relative to HCT116 sh-control cells. From these results, we identified CDK2 as a direct target of curcumin in colon cancer cells. PMID:24550143

Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neovascularization.

PubMed

Dubrac, Alexandre; Genet, Gael; Ola, Roxana; Zhang, Feng; Pibouin-Fragner, Laurence; Han, Jinah; Zhang, Jiasheng; Thomas, Jean-Léon; Chedotal, Alain; Schwartz, Martin A; Eichmann, Anne

2016-01-26

Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here, we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2- and VEGF-induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, and pathological ocular neovascularization and wound healing, as well. These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2, and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis. © 2015 American Heart Association, Inc.

Enhancing Oral Vaccine Potency by Targeting Intestinal M Cells

PubMed Central

Azizi, Ali; Kumar, Ashok; Diaz-Mitoma, Francisco; Mestecky, Jiri

2010-01-01

The immune system in the gastrointestinal tract plays a crucial role in the control of infection, as it constitutes the first line of defense against mucosal pathogens. The attractive features of oral immunization have led to the exploration of a variety of oral delivery systems. However, none of these oral delivery systems have been applied to existing commercial vaccines. To overcome this, a new generation of oral vaccine delivery systems that target antigens to gut-associated lymphoid tissue is required. One promising approach is to exploit the potential of microfold (M) cells by mimicking the entry of pathogens into these cells. Targeting specific receptors on the apical surface of M cells might enhance the entry of antigens, initiating the immune response and consequently leading to protection against mucosal pathogens. In this article, we briefly review the challenges associated with current oral vaccine delivery systems and discuss strategies that might potentially target mouse and human intestinal M cells. PMID:21085599

Microcinematographic and electron microscopic analysis of target cell lysis induced by cytotoxic T lymphocytes.

PubMed Central

Matter, A

1979-01-01

A study was carried out to determine the sequence of events of T-cell mediated target cell lysis in microcinematography and electron microscopy. Highly efficient cytotoxic T lymphocytes (CTL) were generated in vivo and in vitro using preimmunized spleen cells and purification procedures. Such CTL were highly specific. This specificity correlated well with the number of adhesions formed between CTL and targets and this criterion was used to study killer-target cell interaction. Microcinematography showed that target cell lysis at the single cell level, despite time variations, could be clearly separated into three phases: (a) a recognition phase, visible by random crawling of CTL over the target cell surface until firm contact was established; (b) a post-recognition phase, during which firm contact between CTL and target was maintained without gross modification of either cell; (c) a phase of target cell disintegration, mainly characterized by vigorous blebbing of the cell membrane resulting in a motionless carcass of the target cell but not in its total dissolution. Only later this carcass decayed and formed a necrotic ghost. Electron microscopic observations were put into sequence according to microcinematography. Post-recognition phase was characterized by a tight apposition of the membranes of CTL and target cell. No gap junctions could be observed. During target cell disintegration, profound cytoplasmic and nuclear changes occurred simultaneous with surface blebbing. Most noticeable were extensive internal vacuolization, mitochondrial swelling, nuclear pycnosis and dissolution of the nucleolus. These observations suggested that target cell lysis does not start with a surface phenomenon similar to complement lysis, but a process involving practically the whole cell simultaneously. It is conceivable, therefore, that the signal from the CTL is transmitted across the target cell, and that the switch to sudden cell death is manipulated deep inside the cell. Images

Targeted delivery of siRNA into breast cancer cells via phage fusion proteins.

PubMed

Bedi, Deepa; Gillespie, James W; Petrenko, Vasily A; Ebner, Andreas; Leitner, Michael; Hinterdorfer, Peter; Petrenko, Valery A

2013-02-04

Nucleic acids, including antisense oligonucleotides, small interfering RNA (siRNA), aptamers, and rybozymes, emerged as versatile therapeutics due to their ability to interfere in a well-planned manner with the flow of genetic information from DNA to protein. However, a systemic use of NAs is hindered by their instability in physiological liquids and inability of intracellular accumulation in the site of action. We first evaluated the potential of cancer specific phage fusion proteins as targeting ligands that provide encapsulation, protection, and navigation of siRNA to the target cell. The tumor-specific proteins were isolated from phages that were affinity selected from a landscape phage library against target breast cancer cells. It was found that fusion phage coat protein fpVIII displaying cancer-targeting peptides can effectively encapsulate siRNAs and deliver them into the cells leading to specific silencing of the model gene GAPDH. Complexes of siRNA and phage protein form nanoparticles (nanophages), which were characterized by atomic force microscopy and ELISA, and their stability was demonstrated by resistance of encapsulated siRNA to degradation by serum nucleases. The phage protein/siRNA complexes can make a new type of highly selective, stable, active, and physiologically acceptable cancer nanomedicine.

Combustion-Derived Ultrafine Particles Transport Organic Toxicants to Target Respiratory Cells

PubMed Central

Penn, Arthur; Murphy, Gleeson; Barker, Steven; Henk, William; Penn, Lynn

2005-01-01

Epidemiologic evidence supports associations between inhalation of fine and ultrafine ambient particulate matter [aerodynamic diameter ≤ 2.5 μm (PM2.5)] and increases in cardiovascular/respiratory morbidity and mortality. Less attention has been paid to how the physical and chemical characteristics of these particles may influence their interactions with target cells. Butadiene soot (BDS), produced during combustion of the high-volume petrochemical 1,3-butadiene, is rich in polynuclear aromatic hydrocarbons (PAHs), including known carcinogens. We conducted experiments to characterize BDS with respect to particle size distribution, assembly, PAH composition, elemental content, and interaction with respiratory epithelial cells. Freshly generated, intact BDS is primarily (> 90%) PAH-rich, metals-poor (nickel, chromium, and vanadium concentrations all < 1 ppm) PM2.5, composed of uniformly sized, solid spheres (30–50 nm) in aggregated form. Cells of a human bronchial epithelial cell line (BEAS-2B) exhibit sequential fluorescent responses—a relatively rapid (~ 30 min), bright but diffuse fluorescence followed by the slower (2–4 hr) appearance of punctate cytoplasmic fluorescence—after BDS is added to medium overlying the cells. The fluorescence is associated with PAH localization in the cells. The ultrafine BDS particles move down through the medium to the cell membrane. Fluorescent PAHs are transferred from the particle surface to the cell membrane, cross the membrane into the cytosol, and appear to accumulate in lipid vesicles. There is no evidence that BDS particles pass into the cells. The results demonstrate that uptake of airborne ultrafine particles by target cells is not necessary for transfer of toxicants from the particles to the cells. PMID:16079063

A new prospect in cancer therapy: targeting cancer stem cells to eradicate cancer.

PubMed

Chen, Li-Sha; Wang, An-Xin; Dong, Bing; Pu, Ke-Feng; Yuan, Li-Hua; Zhu, Yi-Min

2012-12-01

According to the cancer stem cell theory, cancers can be initiated by cancer stem cells. This makes cancer stem cells prime targets for therapeutic intervention. Eradicating cancer stem cells by efficient targeting agents may have the potential to cure cancer. In this review, we summarize recent breakthroughs that have improved our understanding of cancer stem cells, and we discuss the therapeutic strategy of targeting cancer stem cells, a promising future direction for cancer stem cell research.

Large-Scale Chemical Similarity Networks for Target Profiling of Compounds Identified in Cell-Based Chemical Screens

PubMed Central

Lo, Yu-Chen; Senese, Silvia; Li, Chien-Ming; Hu, Qiyang; Huang, Yong; Damoiseaux, Robert; Torres, Jorge Z.

2015-01-01

Target identification is one of the most critical steps following cell-based phenotypic chemical screens aimed at identifying compounds with potential uses in cell biology and for developing novel disease therapies. Current in silico target identification methods, including chemical similarity database searches, are limited to single or sequential ligand analysis that have limited capabilities for accurate deconvolution of a large number of compounds with diverse chemical structures. Here, we present CSNAP (Chemical Similarity Network Analysis Pulldown), a new computational target identification method that utilizes chemical similarity networks for large-scale chemotype (consensus chemical pattern) recognition and drug target profiling. Our benchmark study showed that CSNAP can achieve an overall higher accuracy (>80%) of target prediction with respect to representative chemotypes in large (>200) compound sets, in comparison to the SEA approach (60–70%). Additionally, CSNAP is capable of integrating with biological knowledge-based databases (Uniprot, GO) and high-throughput biology platforms (proteomic, genetic, etc) for system-wise drug target validation. To demonstrate the utility of the CSNAP approach, we combined CSNAP's target prediction with experimental ligand evaluation to identify the major mitotic targets of hit compounds from a cell-based chemical screen and we highlight novel compounds targeting microtubules, an important cancer therapeutic target. The CSNAP method is freely available and can be accessed from the CSNAP web server (http://services.mbi.ucla.edu/CSNAP/). PMID:25826798

Glioblastoma Stem Cells as a New Therapeutic Target for Glioblastoma.

PubMed

Kalkan, Rasime

2015-01-01

Primary and secondary glioblastomas (GBMs) are two distinct diseases. The genetic and epigenetic background of these tumors is highly variable. The treatment procedure for these tumors is often unsuccessful because of the cellular heterogeneity and intrinsic ability of the tumor cells to invade healthy tissues. The fatal outcome of these tumors promotes researchers to find out new markers associated with the prognosis and treatment planning. In this communication, the role of glioblastoma stem cells in tumor progression and the malignant behavior of GBMs are summarized with attention to the signaling pathways and molecular regulators that are involved in maintaining the glioblastoma stem cell phenotype. A better understanding of these stem cell-like cells is necessary for designing new effective treatments and developing novel molecular strategies to target glioblastoma stem cells. We discuss hypoxia as a new therapeutic target for GBM. We focus on the inhibition of signaling pathways, which are associated with the hypoxia-mediated maintenance of glioblastoma stem cells, and the knockdown of hypoxia-inducible factors, which could be identified as attractive molecular target approaches for GBM therapeutics.

HLA-targeted flow cytometric sorting of blood cells allows separation of pure and viable microchimeric cell populations.

PubMed

Drabbels, Jos J M; van de Keur, Carin; Kemps, Berit M; Mulder, Arend; Scherjon, Sicco A; Claas, Frans H J; Eikmans, Michael

2011-11-10

Microchimerism is defined by the presence of low levels of nonhost cells in a person. We developed a reliable method for separating viable microchimeric cells from the host environment. For flow cytometric cell sorting, HLA antigens were targeted with human monoclonal HLA antibodies (mAbs). Optimal separation of microchimeric cells (present at a proportion as low as 0.01% in artificial mixtures) was obtained with 2 different HLA mAbs, one targeting the chimeric cells and the other the background cells. To verify purity of separated cell populations, flow-sorted fractions of 1000 cells were processed for DNA analysis by HLA-allele-specific and Y-chromosome-directed real-time quantitative PCR assays. After sorting, PCR signals of chimeric DNA markers in the positive fractions were significantly enhanced compared with those in the presort samples, and they were similar to those in 100% chimeric control samples. Next, we demonstrate applicability of HLA-targeted FACS sorting after pregnancy by separating chimeric maternal cells from child umbilical cord mononuclear cells. Targeting allelic differences with anti-HLA mAbs with FACS sorting allows maximal enrichment of viable microchimeric cells from a background cell population. The current methodology enables reliable microchimeric cell detection and separation in clinical specimens.

Modeling activity and target-dependent developmental cell death of mouse retinal ganglion cells ex vivo.

PubMed

Voyatzis, Sylvie; Muzerelle, Aude; Gaspar, Patricia; Nicol, Xavier

2012-01-01

Programmed cell death is widespread during the development of the central nervous system and serves multiple purposes including the establishment of neural connections. In the mouse retina a substantial reduction of retinal ganglion cells (RGCs) occurs during the first postnatal week, coinciding with the formation of retinotopic maps in the superior colliculus (SC). We previously established a retino-collicular culture preparation which recapitulates the progressive topographic ordering of RGC projections during early post-natal life. Here, we questioned whether this model could also be suitable to examine the mechanisms underlying developmental cell death of RGCs. Brn3a was used as a marker of the RGCs. A developmental decline in the number of Brn3a-immunolabelled neurons was found in the retinal explant with a timing that paralleled that observed in vivo. In contrast, the density of photoreceptors or of starburst amacrine cells increased, mimicking the evolution of these cell populations in vivo. Blockade of neural activity with tetrodotoxin increased the number of surviving Brn3a-labelled neurons in the retinal explant, as did the increase in target availability when one retinal explant was confronted with 2 or 4 collicular slices. Thus, this ex vivo model reproduces the developmental reduction of RGCs and recapitulates its regulation by neural activity and target availability. It therefore offers a simple way to analyze developmental cell death in this classic system. Using this model, we show that ephrin-A signaling does not participate to the regulation of the Brn3a population size in the retina, indicating that eprhin-A-mediated elimination of exuberant projections does not involve developmental cell death.

Bioenergetic Effects of Mitochondrial-Targeted Coenzyme Q Analogs in Endothelial Cells

PubMed Central

Fink, Brian D.; Herlein, Judith A.; Yorek, Mark A.; Fenner, Amanda M.; Kerns, Robert J.

2012-01-01

Mitochondrial-targeted analogs of coenzyme Q (CoQ) are under development to reduce oxidative damage induced by a variety of disease states. However, there is a need to understand the bioenergetic effects of these agents and whether or not these effects are related to redox properties, including their known pro-oxidant effects. We examined the bioenergetic effects of two mitochondrial-targeted CoQ analogs in their quinol forms, mitoquinol (MitoQ) and plastoquinonyl-decyl-triphenylphosphonium (SkQ1), in bovine aortic endothelial cells. We used an extracellular oxygen and proton flux analyzer to assess mitochondrial action at the intact-cell level. Both agents, in dose-dependent fashion, reduced the oxygen consumption rate (OCR) directed at ATP turnover (OCRATP) (IC50 values of 189 ± 13 nM for MitoQ and 181 ± 7 for SKQ1; difference not significant) while not affecting or mildly increasing basal oxygen consumption. Both compounds increased extracellular acidification in the basal state consistent with enhanced glycolysis. Both compounds enhanced mitochondrial superoxide production assessed by using mitochondrial-targeted dihydroethidium, and both increased H2O2 production from mitochondria of cells treated before isolation of the organelles. The manganese superoxide dismutase mimetic manganese(III) tetrakis(1-methyl-4-pyridyl)porphyrin did not alter or actually enhanced the actions of the targeted CoQ analogs to reduce OCRATP. In contrast, N-acetylcysteine mitigated this effect of MitoQ and SkQ1. In summary, our data demonstrate the important bioenergetic effects of targeted CoQ analogs. Moreover, these effects are mediated, at least in part, through superoxide production but depend on conversion to H2O2. These bioenergetic and redox actions need to be considered as these compounds are developed for therapeutic purposes. PMID:22661629

Bioenergetic effects of mitochondrial-targeted coenzyme Q analogs in endothelial cells.

PubMed

Fink, Brian D; Herlein, Judith A; Yorek, Mark A; Fenner, Amanda M; Kerns, Robert J; Sivitz, William I

2012-09-01

Mitochondrial-targeted analogs of coenzyme Q (CoQ) are under development to reduce oxidative damage induced by a variety of disease states. However, there is a need to understand the bioenergetic effects of these agents and whether or not these effects are related to redox properties, including their known pro-oxidant effects. We examined the bioenergetic effects of two mitochondrial-targeted CoQ analogs in their quinol forms, mitoquinol (MitoQ) and plastoquinonyl-decyl-triphenylphosphonium (SkQ1), in bovine aortic endothelial cells. We used an extracellular oxygen and proton flux analyzer to assess mitochondrial action at the intact-cell level. Both agents, in dose-dependent fashion, reduced the oxygen consumption rate (OCR) directed at ATP turnover (OCR(ATP)) (IC₅₀ values of 189 ± 13 nM for MitoQ and 181 ± 7 for SKQ1; difference not significant) while not affecting or mildly increasing basal oxygen consumption. Both compounds increased extracellular acidification in the basal state consistent with enhanced glycolysis. Both compounds enhanced mitochondrial superoxide production assessed by using mitochondrial-targeted dihydroethidium, and both increased H₂O₂ production from mitochondria of cells treated before isolation of the organelles. The manganese superoxide dismutase mimetic manganese(III) tetrakis(1-methyl-4-pyridyl)porphyrin did not alter or actually enhanced the actions of the targeted CoQ analogs to reduce OCR(ATP). In contrast, N-acetylcysteine mitigated this effect of MitoQ and SkQ1. In summary, our data demonstrate the important bioenergetic effects of targeted CoQ analogs. Moreover, these effects are mediated, at least in part, through superoxide production but depend on conversion to H₂O₂. These bioenergetic and redox actions need to be considered as these compounds are developed for therapeutic purposes.

MicroRNA-138 inhibits proliferation of cervical cancer cells by targeting c-Met.

PubMed

Li, B; Yang, X-X; Wang, D; Ji, H-K

2016-01-01

MicroRNAs (miRNAs) function as important post-transcriptional regulators involved in a wide range of biological behaviors. MicroRNA-138 (miR-138) has been shown to play a critical role in tumor pathogenesis, the present study aimed to investigate the role of miR-138 in cervical cancer. CCK-8 assay was performed to measure the viabilities of cancer cells. Quantitative real-time PCR (qRT-PCR) and western blot were used to detect the mRNA and protein expression, respectively. Moreover, the miRNA target genes were validated with luciferase activity assay. In the current study, we found that the expression of miR-138 was significantly down-regulated in cervical cancer tissues compared to the adjacent non-cancer tissues. CCK-8 assay showed that over-expression of miR-138 suppressed the proliferation of four cervical cancer cell lines including HeLa, SiHa, C33A and CaSki. By contrast, down-regulation of miR-138 promoted the growth of cervical cancer cells. In addition, increased expression of miR-138 led to a reduction in c-Met expression, whereas inhibition of miR-138 enhanced c-Met levels in cervical cancer cells. The luciferase reporter assay showed that c-Met was a direct target of miR-138 in cervical cancer cells. These findings demonstrated that miR-138 inhibited cervical cancer cells proliferation via c-Met, providing a novel target for the molecular treatment of cervical cancer.

ErbB-targeted CAR T-cell immunotherapy of cancer.

PubMed

Whilding, Lynsey M; Maher, John

2015-01-01

Chimeric antigen receptor (CAR) based immunotherapy has been under development for the last 25 years and is now a promising new treatment modality in the field of cancer immunotherapy. The approach involves genetically engineering T cells to target malignant cells through expression of a bespoke fusion receptor that couples an HLA-independent antigen recognition domain to one or more intracellular T-cell activating modules. Multiple clinical trials are now underway in several centers to investigate CAR T-cell immunotherapy of diverse hematologic and solid tumor types. The most successful results have been achieved in the treatment of patients with B-cell malignancies, in whom several complete and durable responses have been achieved. This review focuses on the preclinical and clinical development of CAR T-cell immunotherapy of solid cancers, targeted against members of the ErbB family.

Use of an activated beta-catenin to identify Wnt pathway target genes in caenorhabditis elegans, including a subset of collagen genes expressed in late larval development.

PubMed

Jackson, Belinda M; Abete-Luzi, Patricia; Krause, Michael W; Eisenmann, David M

2014-04-16

The Wnt signaling pathway plays a fundamental role during metazoan development, where it regulates diverse processes, including cell fate specification, cell migration, and stem cell renewal. Activation of the beta-catenin-dependent/canonical Wnt pathway up-regulates expression of Wnt target genes to mediate a cellular response. In the nematode Caenorhabditis elegans, a canonical Wnt signaling pathway regulates several processes during larval development; however, few target genes of this pathway have been identified. To address this deficit, we used a novel approach of conditionally activated Wnt signaling during a defined stage of larval life by overexpressing an activated beta-catenin protein, then used microarray analysis to identify genes showing altered expression compared with control animals. We identified 166 differentially expressed genes, of which 104 were up-regulated. A subset of the up-regulated genes was shown to have altered expression in mutants with decreased or increased Wnt signaling; we consider these genes to be bona fide C. elegans Wnt pathway targets. Among these was a group of six genes, including the cuticular collagen genes, bli-1 col-38, col-49, and col-71. These genes show a peak of expression in the mid L4 stage during normal development, suggesting a role in adult cuticle formation. Consistent with this finding, reduction of function for several of the genes causes phenotypes suggestive of defects in cuticle function or integrity. Therefore, this work has identified a large number of putative Wnt pathway target genes during larval life, including a small subset of Wnt-regulated collagen genes that may function in synthesis of the adult cuticle.

GEM-loaded magnetic albumin nanospheres modified with cetuximab for simultaneous targeting, magnetic resonance imaging, and double-targeted thermochemotherapy of pancreatic cancer cells.

PubMed

Wang, Ling; An, Yanli; Yuan, Chenyan; Zhang, Hao; Liang, Chen; Ding, Fengan; Gao, Qi; Zhang, Dongsheng

2015-01-01

Targeted delivery is a promising strategy to improve the diagnostic imaging and therapeutic effect of cancers. In this paper, novel cetuximab (C225)-conjugated, gemcitabine (GEM)-containing magnetic albumin nanospheres (C225-GEM/MANs) were fabricated and applied as a theranostic nanocarrier to conduct simultaneous targeting, magnetic resonance imaging (MRI), and double-targeted thermochemotherapy against pancreatic cancer cells. Fe3O4 nanoparticles (NPs) and GEM co-loaded albumin nanospheres (GEM/MANs) were prepared, and then C225 was further conjugated to synthesize C225-GEM/MANs. Their morphology, mean particle size, GEM encapsulation ratio, specific cell-binding ability, and thermal dynamic profiles were characterized. The effects of discriminating different EGFR-expressing pancreatic cancer cells (AsPC-1 and MIA PaCa-2) and monitoring cellular targeting effects were assessed by targeted MRI. Lastly, the antitumor efficiency of double/C225/magnetic-targeted and nontargeted thermochemotherapy was compared with chemotherapy alone using 3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and flow cytometry (FCM) assay. When treated with targeted nanospheres, AsPC-1 cells showed a significantly less intense MRI T2 signal than MIA PaCa-2 cells, while both cells had similar signal strength when incubated with nontargeted nanospheres. T2 signal intensity was significantly lower when magnetic and C225 targeting were combined, rather than used alone. The inhibitory and apoptotic rates of each thermochemotherapy group were significantly higher than those of the chemotherapy-alone groups. Additionally, both MTT and FCM analysis verified that double-targeted thermochemotherapy had the highest targeted killing efficiency among all groups. The C225-GEM/MANs can distinguish various EGFR-expressing live pancreatic cancer cells, monitor diverse cellular targeting effects using targeted MRI imaging, and efficiently mediate double-targeted thermochemotherapy

Targeting the cancer initiating cell: the Achilles' heel of cancer.

PubMed

McCubrey, James A; Chappell, William H; Abrams, Stephen L; Franklin, Richard A; Long, Jacquelyn M; Sattler, Jennifer A; Kempf, C Ruth; Laidler, Piotr; Steelman, Linda S

2011-01-01

We have isolated cell with the cancer initiating cell (CIC) phenotype from PC3 cells. The PC3/(CIC) cells are more resistant than the PC3/(BC) cells to chemotherapeutic drugs such as docetaxel which is used to treat prostate cancer. Thus these prostate CICs could lay dormant and persist even after chemotherapeutic drug treatment. Then when the chemotherapeutic drug is removed, they could potentially repopulate the original tumor site or metastize to a distant site. However, the prostate CICs were not significantly more resistant to drugs which target EGFR, NF-κB, Smo and the natural product genistein. Interesting the prostate CICs could be rendered more sensitive to docetaxel by inclusion of suboptimal doses of genistein, cyclopamine, and EGFR inhibitors. In contrast, addition of suboptimal amounts of genistein, cyclopamine, or EGFR inhibitors did not increase the sensitivity of the PC/(BC) cells to docetaxel. Similar results were observed when combination experiments were performed with cyclopamine and suboptimal doses of either genistein or docetaxel. The BC cells are usually more rapidly proliferating than the CICs. Thus the CICs are not as sensitive to docetaxel which targets replication. In contrast, the CICs could be rendered sensitive to docetaxel or cyclopamine by co-treatment with certain other drugs, including the natural product genistein which is present in the human diet of many people, especially Asians. Genistein is by itself only weakly toxic to prostate and other cancer cells. That is probably one of the big reasons that it can be used as a dietary supplement for prostate and breast cancers. It is clear from our studies that low doses of genistein can increase the sensitivity of prostate CICs to drugs such as docetaxel and cyclopamine, two drugs either used or under consideration for prostate cancer therapy.

Phenotypic high-throughput screening elucidates target pathway in breast cancer stem cell-like cells.

PubMed

Carmody, Leigh C; Germain, Andrew R; VerPlank, Lynn; Nag, Partha P; Muñoz, Benito; Perez, Jose R; Palmer, Michelle A J

2012-10-01

Cancer stem cells (CSCs) are resistant to standard cancer treatments and are likely responsible for cancer recurrence, but few therapies target this subpopulation. Due to the difficulty in propagating CSCs outside of the tumor environment, previous work identified CSC-like cells by inducing human breast epithelial cells into an epithelial-to-mesenchymal transdifferentiated state (HMLE_sh_ECad). A phenotypic screen was conducted against HMLE_sh_ECad with 300 718 compounds from the Molecular Libraries Small Molecule Repository to identify selective inhibitors of CSC growth. The screen yielded 2244 hits that were evaluated for toxicity and selectivity toward an isogenic control cell line. An acyl hydrazone scaffold emerged as a potent and selective scaffold targeting HMLE_sh_ECad. Fifty-three analogues were acquired and tested; compounds ranged in potency from 790 nM to inactive against HMLE_sh_ECad. Of the analogues, ML239 was best-in-class with an IC(50)= 1.18 µM against HMLE_sh_ECad, demonstrated a >23-fold selectivity over the control line, and was toxic to another CSC-like line, HMLE_shTwist, and a breast carcinoma cell line, MDA-MB-231. Gene expression studies conducted with ML239-treated cells showed altered gene expression in the NF-κB pathway in the HMLE_sh_ECad line but not in the isogenic control line. Future studies will be directed toward the identification of ML239 target(s).

miR-137 inhibits the invasion of melanoma cells through downregulation of multiple oncogenic target genes.

PubMed

Luo, Chonglin; Tetteh, Paul W; Merz, Patrick R; Dickes, Elke; Abukiwan, Alia; Hotz-Wagenblatt, Agnes; Holland-Cunz, Stefan; Sinnberg, Tobias; Schittek, Birgit; Schadendorf, Dirk; Diederichs, Sven; Eichmüller, Stefan B

2013-03-01

MicroRNAs are small noncoding RNAs that regulate gene expression and have important roles in various types of cancer. Previously, miR-137 was reported to act as a tumor suppressor in different cancers, including malignant melanoma. In this study, we show that low miR-137 expression is correlated with poor survival in stage IV melanoma patients. We identified and validated two genes (c-Met and YB1) as direct targets of miR-137 and confirmed two previously known targets, namely enhancer of zeste homolog 2 (EZH2) and microphthalmia-associated transcription factor (MITF). Functional studies showed that miR-137 suppressed melanoma cell invasion through the downregulation of multiple target genes. The decreased invasion caused by miR-137 overexpression could be phenocopied by small interfering RNA knockdown of EZH2, c-Met, or Y box-binding protein 1 (YB1). Furthermore, miR-137 inhibited melanoma cell migration and proliferation. Finally, miR-137 induced apoptosis in melanoma cell lines and decreased BCL2 levels. In summary, our study confirms that miR-137 acts as a tumor suppressor in malignant melanoma and reveals that miR-137 regulates multiple targets including c-Met, YB1, EZH2, and MITF.

Targeting myeloid-derived suppressor cells for cancer immunotherapy.

PubMed

Liu, Yijun; Wei, Guowei; Cheng, Wesley A; Dong, Zhenyuan; Sun, Han; Lee, Vincent Y; Cha, Soung-Chul; Smith, D Lynne; Kwak, Larry W; Qin, Hong

2018-05-31

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells with an immune suppressive phenotype. They represent a critical component of the immune suppressive niche described in cancer, where they support immune escape and tumor progression through direct effects on both the innate and adaptive immune responses, largely by contributing to maintenance of a high oxidative stress environment. The number of MDSCs positively correlates with protumoral activity, and often diminishes the effectiveness of immunotherapies, which is particularly problematic with the emergence of personalized medicine. Approaches targeting MDSCs showed promising results in preclinical studies and are under active investigation in clinical trials in combination with various immune checkpoint inhibitors. In this review, we discuss MDSC targets and therapeutic approaches targeting MDSC that have the aim of enhancing the existing tumor therapies.

Many si/shRNAs can kill cancer cells by targeting multiple survival genes through an off-target mechanism

PubMed Central

van Dongen, Stijn; Haluck-Kangas, Ashley; Sarshad, Aishe A; Bartom, Elizabeth T; Kim, Kwang-Youn A; Scholtens, Denise M; Hafner, Markus; Zhao, Jonathan C; Murmann, Andrea E

2017-01-01

Over 80% of multiple-tested siRNAs and shRNAs targeting CD95 or CD95 ligand (CD95L) induce a form of cell death characterized by simultaneous activation of multiple cell death pathways preferentially killing transformed and cancer stem cells. We now show these si/shRNAs kill cancer cells through canonical RNAi by targeting the 3’UTR of critical survival genes in a unique form of off-target effect we call DISE (death induced by survival gene elimination). Drosha and Dicer-deficient cells, devoid of most miRNAs, are hypersensitive to DISE, suggesting cellular miRNAs protect cells from this form of cell death. By testing 4666 shRNAs derived from the CD95 and CD95L mRNA sequences and an unrelated control gene, Venus, we have identified many toxic sequences - most of them located in the open reading frame of CD95L. We propose that specific toxic RNAi-active sequences present in the genome can kill cancer cells. PMID:29063830

Programmed Cell Death-1/Programmed Death-ligand 1 Pathway: A New Target for Sepsis.

PubMed

Liu, Qiang; Li, Chun-Sheng

2017-04-20

Sepsis remains a leading cause of death in many Intensive Care Units worldwide. Immunosuppression has been a primary focus of sepsis research as a key pathophysiological mechanism. Given the important role of the negative costimulatory molecules programmed cell death-1 (PD-1) and programmed death-ligand 1 (PD-L1) in the occurrence of immunosuppression during sepsis, we reviewed literatures related to the PD-1/PD-L1 pathway to examine its potential as a new target for sepsis treatment. Studies of the association between PD-1/PD-L1 and sepsis published up to January 31, 2017, were obtained by searching the PubMed database. English language studies, including those based on animal models, clinical research, and reviews, with data related to PD-1/PD-L1 and sepsis, were evaluated. Immunomodulatory therapeutics could reverse the deactivation of immune cells caused by sepsis and restore immune cell activation and function. Blockade of the PD-1/PD-L1 pathway could reduce the exhaustion of T-cells and enhance the proliferation and activation of T-cells. The anti-PD-1/PD-L1 pathway shows promise as a new target for sepsis treatment. This review provides a basis for clinical trials and future studies aimed at revaluating the efficacy and safety of this targeted approach.

Cryostat including heater to heat a target

DOEpatents

Pehl, Richard H.; Madden, Norman W.; Malone, Donald F.

1990-01-01

A cryostat is provided which comprises a vacuum vessel; a target disposed within the vacuum vessel; a heat sink disposed within the vacuum vesssel for absorbing heat from the detector; a cooling mechanism for cooling the heat sink; a cryoabsorption mechanism for cryoabsorbing residual gas within the vacuum vessel; and a heater for maintaining the target above a temperature at which the residual gas is cryoabsorbed in the course of cryoabsorption of the residual gas by the cryoabsorption mechanism.

RUNX1 promotes cell growth in human T-cell acute lymphoblastic leukemia by transcriptional regulation of key target genes.

PubMed

Jenkins, Catherine E; Gusscott, Samuel; Wong, Rachel J; Shevchuk, Olena O; Rana, Gurneet; Giambra, Vincenzo; Tyshchenko, Kateryna; Islam, Rashedul; Hirst, Martin; Weng, Andrew P

2018-05-04

RUNX1 is frequently mutated in T-cell acute lymphoblastic leukemia (T-ALL). The spectrum of RUNX1 mutations has led to the notion that it acts as a tumor suppressor in this context; however, other studies have placed RUNX1 along with transcription factors TAL1 and NOTCH1 as core drivers of an oncogenic transcriptional program. To reconcile these divergent roles, we knocked down RUNX1 in human T-ALL cell lines and deleted Runx1 or Cbfb in primary mouse T-cell leukemias. RUNX1 depletion consistently resulted in reduced cell proliferation and increased apoptosis. RUNX1 upregulated variable sets of target genes in each cell line, but consistently included a core set of oncogenic effectors including IGF1R and NRAS. Our results support the conclusion that RUNX1 has a net positive effect on cell growth in the context of established T-ALL. Copyright © 2018. Published by Elsevier Inc.

New generation of oral mucosal vaccines targeting dendritic cells.

PubMed

Owen, Jennifer L; Sahay, Bikash; Mohamadzadeh, Mansour

2013-12-01

As most infectious organisms gain entry at mucosal surfaces, there is a great deal of interest in developing vaccines that elicit effective mucosal immune responses against pathogen challenge. Targeted vaccination is one of the most effective methods available to prevent and control infectious diseases. Mucosal vaccines can offer lower costs, better accessibility, needle free delivery, and a higher capacity for mass immunizations during pandemics. Both local mucosal immunity and robust systemic responses can be achieved through mucosal vaccination. Recent progress in understanding the molecular and cellular components of the mucosal immune system have allowed for the development of a novel mucosal vaccine platform utilizing specific dendritic cell-targeting peptides and orally administered lactobacilli to elicit efficient antigen specific immune responses against infections, including Bacillus anthracis in experimental models of disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Lysis of autologous human macrophages by lymphokine-activated killer cells: interaction of effector cell and target cell conjugates analyzed by scanning electron microscopy.

PubMed

Streck, R J; Helinski, E H; Ovak, G M; Pauly, J L

1990-09-01

Lymphokine (i.e., interleukin 2; IL-2)-activated killer (LAK) cells derived from normal human blood are known to destroy human tumor target cells. Accordingly, immunotherapy modalities using IL-2, either alone or in combination with LAK cells, have been evaluated for eradicating metastatic cancer. In studies conducted to characterize receptors on LAK cell membrane ultrastructures, we observed that LAK cells kill autologous human monocyte-derived macrophages (M phi). In these experiments, peripheral blood mononuclear cells of a healthy adult donor were cultured to generate LAK cells and autologous non-adherent M phi. Thereafter, conjugates were prepared by incubating for 3 h autologous populations of LAK cells and M phi. Examination of the conjugates by scanning electron microscopy (SEM) identified LAK cell-mediated killing of M phi. Moreover, SEM analysis of the LAK cell membrane architecture identified microvilli-like ultrastructures that provided a physical bridge that joined together the LAK cell and M phi. The immunological mechanism(s) underling LAK cell killing of autologous M phi is not known; nevertheless, these conjugates will provide a useful model to study membrane receptors on ultrastructures that mediate the initial stages of cytolysis that include target cell recognition and cell-to-cell adhesion. The results of our observations and the findings of other investigators who have also demonstrated LAK cell killing of autologous normal human leukocytes are discussed in the context of the association of IL-2 and IL-2-activated killer cells with side effects observed in ongoing clinical trials and with autoimmune disorders.

Cryostat including heater to heat a target

DOEpatents

Pehl, R.H.; Madden, N.W.; Malone, D.F.

1990-09-11

A cryostat is provided which comprises a vacuum vessel; a target disposed within the vacuum vessel; a heat sink disposed within the vacuum vessel for absorbing heat from the detector; a cooling mechanism for cooling the heat sink; a cryoabsorption mechanism for cryoabsorbing residual gas within the vacuum vessel; and a heater for maintaining the target above a temperature at which the residual gas is cryoabsorbed in the course of cryoabsorption of the residual gas by the cryoabsorption mechanism. 2 figs.

EGFR-targeted granzyme B expressed in NK cells enhances natural cytotoxicity and mediates specific killing of tumor cells.

PubMed

Oberoi, Pranav; Jabulowsky, Robert A; Bähr-Mahmud, Hayat; Wels, Winfried S

2013-01-01

Natural killer (NK) cells are highly specialized effectors of the innate immune system that hold promise for adoptive cancer immunotherapy. Their cell killing activity is primarily mediated by the pro-apoptotic serine protease granzyme B (GrB), which enters targets cells with the help of the pore-forming protein perforin. We investigated expression of a chimeric GrB fusion protein in NK cells as a means to augment their antitumoral activity. For selective targeting to tumor cells, we fused the epidermal growth factor receptor (EGFR) peptide ligand transforming growth factor α (TGFα) to human pre-pro-GrB. Established human NKL natural killer cells transduced with a lentiviral vector expressed this GrB-TGFα (GrB-T) molecule in amounts comparable to endogenous wildtype GrB. Activation of the genetically modified NK cells by cognate target cells resulted in the release of GrB-T together with endogenous granzymes and perforin, which augmented the effector cells' natural cytotoxicity against NK-sensitive tumor cells. Likewise, GrB-T was released into the extracellular space upon induction of degranulation with PMA and ionomycin. Secreted GrB-T fusion protein displayed specific binding to EGFR-overexpressing tumor cells, enzymatic activity, and selective target cell killing in the presence of an endosomolytic activity. Our data demonstrate that ectopic expression of a targeted GrB fusion protein in NK cells is feasible and can enhance antitumoral activity of the effector cells.

A Cell-Based Screen Reveals that the Albendazole Metabolite, Albendazole Sulfone, Targets Wolbachia

PubMed Central

Bray, Walter M.; White, Pamela M.; Ruybal, Jordan; Lokey, R. Scott; Debec, Alain; Sullivan, William

2012-01-01

Wolbachia endosymbionts carried by filarial nematodes give rise to the neglected diseases African river blindness and lymphatic filariasis afflicting millions worldwide. Here we identify new Wolbachia-disrupting compounds by conducting high-throughput cell-based chemical screens using a Wolbachia-infected, fluorescently labeled Drosophila cell line. This screen yielded several Wolbachia-disrupting compounds including three that resembled Albendazole, a widely used anthelmintic drug that targets nematode microtubules. Follow-up studies demonstrate that a common Albendazole metabolite, Albendazole sulfone, reduces intracellular Wolbachia titer both in Drosophila melanogaster and Brugia malayi, the nematode responsible for lymphatic filariasis. Significantly, Albendazole sulfone does not disrupt Drosophila microtubule organization, suggesting that this compound reduces titer through direct targeting of Wolbachia. Accordingly, both DNA staining and FtsZ immunofluorescence demonstrates that Albendazole sulfone treatment induces Wolbachia elongation, a phenotype indicative of binary fission defects. This suggests that the efficacy of Albendazole in treating filarial nematode-based diseases is attributable to dual targeting of nematode microtubules and their Wolbachia endosymbionts. PMID:23028321

Killing of targets by effector CD8 T cells in the mouse spleen follows the law of mass action

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ganusov, Vitaly V

2009-01-01

In contrast with antibody-based vaccines, it has been difficult to measure the efficacy of T cell-based vaccines and to correlate the efficacy of CD8 T cell responses with protection again viral infections. In part, this difficulty is due to poor understanding of the in vivo efficacy of CD8 T cells produced by vaccination. Using a: recently developed experimental method of in vivo cytotoxicity we have investigated quantitative aspects of killing of peptide-pulsed targets by effector and memory CD8 T cells, specific to three epitopes of lymphocytic choriomeningitis virus (LCMV), in the mouse spleen. By analyzing data on killing of targetsmore » with varying number of epitope-specific effector and memory CD8 T cells, we find that killing of targets by effectors follows the law of mass-action, that is the death rate of peptide-pulsed targets is proportional to the frequency of CTLs in the spleen. In contrast, killing of targets by memory CD8 T cells does not follow the mass action law because the death rate of targets saturates at high frequencies of memory CD8 T cells. For both effector and memory cells, we also find little support for the killing term that includes the decrease of the death rate of targets with target cell density. Interestingly, our analysis suggests that at low CD8 T cell frequencies, memory CD8 T cells on the per capita basis are more efficient at killing peptide-pulsed targets than effectors, but at high frequencies, effectors are more efficient killers than memory T cells. Comparison of the estimated killing efficacy of effector T cells with the value that is predicted from theoretical physics and based on motility of T cells in lymphoid tissues, suggests that limiting step in the killing of peptide-pulsed targets is delivering the lethal hit and not finding the target. Our results thus form a basis for quantitative understanding of the process of killing of virus-infected cells by T cell responses in tissues and can be used to correlate the

Adoptive therapy with CAR redirected T cells: the challenges in targeting solid tumors.

PubMed

Abken, Hinrich

2015-01-01

Recent spectacular success in the adoptive cell therapy of leukemia and lymphoma with chimeric antigen receptor (CAR)-modified T cells raised the expectations that this therapy may be efficacious in a wide range of cancer entities. The expectations are based on the predefined specificity of CAR T cells by an antibody-derived binding domain that acts independently of the natural T-cell receptor, recognizes targets independently of presentation by the major histocompatibility complex and allows targeting toward virtually any cell surface antigen. We here discuss that targeting CAR T cells toward solid tumors faces certain circumstances critical for the therapeutic success. Targeting tumor stroma and taking advantage of TRUCK cells, in other words, CAR T cells with inducible release of a transgenic payload, are some strategies envisaged to overcome current limitations in the near future.

MicroRNA-203 Induces Apoptosis by Targeting Bmi-1 in YD-38 Oral Cancer Cells.

PubMed

Kim, Jae-Sung; Choi, Dae Woo; Kim, Chun Sung; Yu, Sun-Kyoung; Kim, Heung-Joong; Go, Dae-San; Lee, Seul Ah; Moon, Sung Min; Kim, Su Gwan; Chun, Hong Sung; Kim, Jeongsun; Kim, Jong-Keun; Kim, DO Kyung

2018-06-01

MicroRNAs (miRNAs) are closely associated with a number of cellular processes, including cell development, differentiation, proliferation, carcinogenesis, and apoptosis. The aim of the present study was to elucidate the molecular mechanisms underlying the tumor suppressor activity of miRNA-203 (miR-203) in YD-38 human oral cancer cells. Polymerase chain reaction analysis, MTT assay, DNA fragmentation assay, fluorescence-activated cell-sorting analysis, gene array, immunoblotting, and luciferase assay were carried out in YD-38 cells. miR-203 expression was significantly down-regulated in YD-38 cells compared to expression levels in normal human oral keratinocytes. miR-203 decreased the viability of YD-38 cells in a time- and dose-dependent manner. In addition, over-expression of miR-203 significantly increased not only DNA segmentation, but also the apoptotic population of YD-38 cells. These results indicate that miR-203 overexpression induces apoptosis in YD-38 cells. Target gene array analysis revealed that the expression of the polycomb complex protein gene Bmi-1, a representative oncogene, was significantly down-regulated by miR-203 in YD-38 cells. Moreover, both mRNA and protein levels of Bmi-1 were significantly reduced in YD-38 cells transfected with miR-203. These results indicate that Bmi-1 is a target gene of miR-203. A luciferase reporter assay confirmed that miR-203 suppressed Bmi-1 expression by directly targeting the 3'-untranslated region. miR-203 induces apoptosis in YD-38 cells by directly targeting Bmi-1, which suggests its possible application as an anti-cancer therapeutic. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Identification of Wnt Pathway Target Genes Regulating the Division and Differentiation of Larval Seam Cells and Vulval Precursor Cells in Caenorhabditis elegans.

PubMed

Gorrepati, Lakshmi; Krause, Michael W; Chen, Weiping; Brodigan, Thomas M; Correa-Mendez, Margarita; Eisenmann, David M

2015-06-05

The evolutionarily conserved Wnt/β-catenin signaling pathway plays a fundamental role during metazoan development, regulating numerous processes including cell fate specification, cell migration, and stem cell renewal. Wnt ligand binding leads to stabilization of the transcriptional effector β-catenin and upregulation of target gene expression to mediate a cellular response. During larval development of the nematode Caenorhabditis elegans, Wnt/β-catenin pathways act in fate specification of two hypodermal cell types, the ventral vulval precursor cells (VPCs) and the lateral seam cells. Because little is known about targets of the Wnt signaling pathways acting during larval VPC and seam cell differentiation, we sought to identify genes regulated by Wnt signaling in these two hypodermal cell types. We conditionally activated Wnt signaling in larval animals and performed cell type-specific "mRNA tagging" to enrich for VPC and seam cell-specific mRNAs, and then used microarray analysis to examine gene expression compared to control animals. Two hundred thirty-nine genes activated in response to Wnt signaling were identified, and we characterized 50 genes further. The majority of these genes are expressed in seam and/or vulval lineages during normal development, and reduction of function for nine genes caused defects in the proper division, fate specification, fate execution, or differentiation of seam cells and vulval cells. Therefore, the combination of these techniques was successful at identifying potential cell type-specific Wnt pathway target genes from a small number of cells and at increasing our knowledge of the specification and behavior of these C. elegans larval hypodermal cells. Copyright © 2015 Gorrepati et al.

Targeting human liver cancer cells with lactobionic acid-G(4)-PAMAM-FITC sorafenib loaded dendrimers.

PubMed

Iacobazzi, Rosa Maria; Porcelli, Letizia; Lopedota, Angela Assunta; Laquintana, Valentino; Lopalco, Antonio; Cutrignelli, Annalisa; Altamura, Emiliano; Di Fonte, Roberta; Azzariti, Amalia; Franco, Massimo; Denora, Nunzio

2017-08-07

Reported here is the synthesis and biological evaluation of the asialoglycoprotein receptor (ASGP-R) targeted fourth generation poliamidoamine dendrimer (G(4)-PAMAM) loaded with sorafenib. The ASGP-R targeted dendrimer was obtained by conjugation of Lactobionic acid (La) to the G(4)-PAMAM dendrimer, followed by acetylation (Ac) of the free amino groups in order to reduce the non-specific interactions with the cell membrane. Moreover, by additionally grafting fluorescein (FITC), it was easy to characterize the internalization pathway and the intracellular fate of the targeted dendrimer Ac-La-G(4)-PAMAM-FITC. In vitro experiments performed on HepG-2 and HLE cell lines, allowed to study the ability of the dendrimers to affect the cell vitality. Confocal microscopy and cytofluorimetric analysis confirmed higher binding and uptake ability of the Ac-La-G(4)-PAMAM-FITC dendrimer in well differentiated and ASGP-R expressing human liver cancer cell line HepG-2 compared non-expressing HLE cells. Ac-La-G(4)-PAMAM-FITC dendrimer loaded with sorafenib was stable and showed sustained sorafenib release. As evidenced by the cytotoxicity studies, sorafenib included in the dendrimer maintained its effectiveness, and was able to produce a longer lasting effect over the time compared to molar equivalent doses of free sorafenib. This new targeted dendrimer appears to be a suitable carrier for the delivery of sorafenib to liver cancer cells expressing ASGP-R. Copyright © 2017 Elsevier B.V. All rights reserved.

T cells which proliferate in response to concanavalin A include cells which proliferate in mixed leucocyte reactions.

PubMed

Watanabe, T; Fathman, C G; Coutinho, A

1977-09-01

Selection in long-term culture of alloreactive T cells, by successive in vitro restimulation with semi-allogeneic cells, results in primed responder cell populations which maintain full proliferative reactivity to allogeneic cells as well as to the T cell mitogens concanavalin A (Con A) and phytohemagglutinin (PHA) but are depleted of cells which can effect target cell destruction in either a specific or nonspecific manner. Con A-induced T cell blasts (selected by velocity sedimentation) can revert to small resting lymphocytes in the presence of inert "filler" cells. Con A blasts which have reverted, readily proliferate in response to Con A or allogeneic stimulator cells but are largely depleted of effector killer cells and PHA-responsive cells.

Clinical impact of targeted therapies in patients with metastatic clear-cell renal cell carcinoma

PubMed Central

Nerich, Virginie; Hugues, Marion; Paillard, Marie Justine; Borowski, Laëtitia; Nai, Thierry; Stein, Ulrich; Nguyen Tan Hon, Thierry; Montcuquet, Philippe; Maurina, Tristan; Mouillet, Guillaume; Kleinclauss, François; Pivot, Xavier; Limat, Samuel; Thiery-Vuillemin, Antoine

2014-01-01

Introduction The aim of this retrospective clinical study was to assess, in the context of the recent evolution of systemic therapies, the potential effect of targeted therapies on overall survival (OS) of patients with metastatic clear-cell renal cell carcinoma (mccRCC) in daily practice. Patients and methods All consecutive patients with histologically confirmed mccRCC who received systemic therapy between January 2000 and December 2010 in two oncology treatment centers in our Franche-Comté region in eastern France were included in the analysis. The primary end point was OS. The analysis of prognostic factors was performed using a two-step approach: univariate then multivariate analysis with a stepwise Cox proportional hazards regression model. Results For the entire cohort of 111 patients, the median OS was 17 months (95% confidence interval [CI]; 13–22 months) and the two-year OS was 39%. Three prognostic factors were independent predictors of long survival: prior nephrectomy (hazard ratio =0.38 [0.22–0.64], P<0.0001); systemic therapy by targeted therapy (hazard ratio =0.50 [0.31–0.80], P=0.005); and lack of liver metastasis (hazard ratio =0.43 [0.22–0.82], P=0.002). Median OS was 21 months [14–29 months] for patients who received at least one targeted therapy compared with 12 months [7–15 months] for patients who were treated only by immunotherapy agents (P=0.003). Conclusion Our results suggest that targeted therapies are associated with improved OS in comparison with cytokines, which is in line with other publications. PMID:24600236

Personalized targeted therapy for esophageal squamous cell carcinoma

PubMed Central

Kang, Xiaozheng; Chen, Keneng; Li, Yicheng; Li, Jianying; D'Amico, Thomas A; Chen, Xiaoxin

2015-01-01

Esophageal squamous cell carcinoma continues to heavily burden clinicians worldwide. Researchers have discovered the genomic landscape of esophageal squamous cell carcinoma, which holds promise for an era of personalized oncology care. One of the most pressing problems facing this issue is to improve the understanding of the newly available genomic data, and identify the driver-gene mutations, pathways, and networks. The emergence of a legion of novel targeted agents has generated much hope and hype regarding more potent treatment regimens, but the accuracy of drug selection is still arguable. Other problems, such as cancer heterogeneity, drug resistance, exceptional responders, and side effects, have to be surmounted. Evolving topics in personalized oncology, such as interpretation of genomics data, issues in targeted therapy, research approaches for targeted therapy, and future perspectives, will be discussed in this editorial. PMID:26167067

Genetic Engineering of T Cells to Target HERV-K, an Ancient Retrovirus on Melanoma.

PubMed

Krishnamurthy, Janani; Rabinovich, Brian A; Mi, Tiejuan; Switzer, Kirsten C; Olivares, Simon; Maiti, Sourindra N; Plummer, Joshua B; Singh, Harjeet; Kumaresan, Pappanaicken R; Huls, Helen M; Wang-Johanning, Feng; Cooper, Laurence J N

2015-07-15

The human endogenous retrovirus (HERV-K) envelope (env) protein is a tumor-associated antigen (TAA) expressed on melanoma but not normal cells. This study was designed to engineer a chimeric antigen receptor (CAR) on T-cell surface, such that they target tumors in advanced stages of melanoma. Expression of HERV-K protein was analyzed in 220 melanoma samples (with various stages of disease) and 139 normal organ donor tissues using immunohistochemical (IHC) analysis. HERV-K env-specific CAR derived from mouse monoclonal antibody was introduced into T cells using the transposon-based Sleeping Beauty (SB) system. HERV-K env-specific CAR(+) T cells were expanded ex vivo on activating and propagating cells (AaPC) and characterized for CAR expression and specificity. This includes evaluating the HERV-K-specific CAR(+) T cells for their ability to kill A375-SM metastasized tumors in a mouse xenograft model. We detected HERV-K env protein on melanoma but not in normal tissues. After electroporation of T cells and selection on HERV-K(+) AaPC, more than 95% of genetically modified T cells expressed the CAR with an effector memory phenotype and lysed HERV-K env(+) tumor targets in an antigen-specific manner. Even though there is apparent shedding of this TAA from tumor cells that can be recognized by HERV-K env-specific CAR(+) T cells, we observed a significant antitumor effect. Adoptive cellular immunotherapy with HERV-K env-specific CAR(+) T cells represents a clinically appealing treatment strategy for advanced-stage melanoma and provides an approach for targeting this TAA on other solid tumors. ©2015 American Association for Cancer Research.

Identification of Wnt Pathway Target Genes Regulating the Division and Differentiation of Larval Seam Cells and Vulval Precursor Cells in Caenorhabditis elegans

PubMed Central

Gorrepati, Lakshmi; Krause, Michael W.; Chen, Weiping; Brodigan, Thomas M.; Correa-Mendez, Margarita; Eisenmann, David M.

2015-01-01

The evolutionarily conserved Wnt/β-catenin signaling pathway plays a fundamental role during metazoan development, regulating numerous processes including cell fate specification, cell migration, and stem cell renewal. Wnt ligand binding leads to stabilization of the transcriptional effector β-catenin and upregulation of target gene expression to mediate a cellular response. During larval development of the nematode Caenorhabditis elegans, Wnt/β-catenin pathways act in fate specification of two hypodermal cell types, the ventral vulval precursor cells (VPCs) and the lateral seam cells. Because little is known about targets of the Wnt signaling pathways acting during larval VPC and seam cell differentiation, we sought to identify genes regulated by Wnt signaling in these two hypodermal cell types. We conditionally activated Wnt signaling in larval animals and performed cell type–specific "mRNA tagging" to enrich for VPC and seam cell–specific mRNAs, and then used microarray analysis to examine gene expression compared to control animals. Two hundred thirty-nine genes activated in response to Wnt signaling were identified, and we characterized 50 genes further. The majority of these genes are expressed in seam and/or vulval lineages during normal development, and reduction of function for nine genes caused defects in the proper division, fate specification, fate execution, or differentiation of seam cells and vulval cells. Therefore, the combination of these techniques was successful at identifying potential cell type–specific Wnt pathway target genes from a small number of cells and at increasing our knowledge of the specification and behavior of these C. elegans larval hypodermal cells. PMID:26048561

Systematic Identification of Combinatorial Drivers and Targets in Cancer Cell Lines

PubMed Central

Tabchy, Adel; Eltonsy, Nevine; Housman, David E.; Mills, Gordon B.

2013-01-01

There is an urgent need to elicit and validate highly efficacious targets for combinatorial intervention from large scale ongoing molecular characterization efforts of tumors. We established an in silico bioinformatic platform in concert with a high throughput screening platform evaluating 37 novel targeted agents in 669 extensively characterized cancer cell lines reflecting the genomic and tissue-type diversity of human cancers, to systematically identify combinatorial biomarkers of response and co-actionable targets in cancer. Genomic biomarkers discovered in a 141 cell line training set were validated in an independent 359 cell line test set. We identified co-occurring and mutually exclusive genomic events that represent potential drivers and combinatorial targets in cancer. We demonstrate multiple cooperating genomic events that predict sensitivity to drug intervention independent of tumor lineage. The coupling of scalable in silico and biologic high throughput cancer cell line platforms for the identification of co-events in cancer delivers rational combinatorial targets for synthetic lethal approaches with a high potential to pre-empt the emergence of resistance. PMID:23577104

Systematic identification of combinatorial drivers and targets in cancer cell lines.

PubMed

Tabchy, Adel; Eltonsy, Nevine; Housman, David E; Mills, Gordon B

2013-01-01

There is an urgent need to elicit and validate highly efficacious targets for combinatorial intervention from large scale ongoing molecular characterization efforts of tumors. We established an in silico bioinformatic platform in concert with a high throughput screening platform evaluating 37 novel targeted agents in 669 extensively characterized cancer cell lines reflecting the genomic and tissue-type diversity of human cancers, to systematically identify combinatorial biomarkers of response and co-actionable targets in cancer. Genomic biomarkers discovered in a 141 cell line training set were validated in an independent 359 cell line test set. We identified co-occurring and mutually exclusive genomic events that represent potential drivers and combinatorial targets in cancer. We demonstrate multiple cooperating genomic events that predict sensitivity to drug intervention independent of tumor lineage. The coupling of scalable in silico and biologic high throughput cancer cell line platforms for the identification of co-events in cancer delivers rational combinatorial targets for synthetic lethal approaches with a high potential to pre-empt the emergence of resistance.

Microchimeric cells in systemic lupus erythematosus: targets or innocent bystanders?

PubMed

Stevens, A M

2006-01-01

During pregnancy maternal and fetal cells commute back and forth leading to fetal microchimerism in the mother and maternal microchimerism in the child that can persist for years after the birth. Chimeric fetal and maternal cells can be hematopoietic or can differentiate into somatic cells in multiple organs, potentially acting as targets for 'autoimmunity' and so have been implicated in the pathogenesis of autoimmune diseases that resemble graft-versus-host disease after stem cell transplantation. Fetal cells have been found in women with systemic lupus erythematosus, both in the blood and a target organ, the kidney, suggesting that they may be involved in pathogenesis. Future studies will address how the host immune system normally tolerates maternal and fetal cells or how the balance may change during autoimmunity.

Free Extracellular miRNA Functionally Targets Cells by Transfecting Exosomes from Their Companion Cells.

PubMed

Bryniarski, Krzysztof; Ptak, Wlodzimierz; Martin, Emilia; Nazimek, Katarzyna; Szczepanik, Marian; Sanak, Marek; Askenase, Philip W

2015-01-01

Lymph node and spleen cells of mice doubly immunized by epicutaneous and intravenous hapten application produce a suppressive component that inhibits the action of the effector T cells that mediate contact sensitivity reactions. We recently re-investigated this phenomenon in an immunological system. CD8+ T lymphocyte-derived exosomes transferred suppressive miR-150 to the effector T cells antigen-specifically due to exosome surface coat of antibody light chains made by B1a lymphocytes. Extracellular RNA (exRNA) is protected from plasma RNases by carriage in exosomes or by chaperones. Exosome transfer of functional RNA to target cells is well described, whereas the mechanism of transfer of exRNA free of exosomes remains unclear. In the current study we describe extracellular miR-150, extracted from exosomes, yet still able to mediate antigen-specific suppression. We have determined that this was due to miR-150 association with antibody-coated exosomes produced by B1a cell companions of the effector T cells, which resulted in antigen-specific suppression of their function. Thus functional cell targeting by free exRNA can proceed by transfecting companion cell exosomes that then transfer RNA cargo to the acceptor cells. This contrasts with the classical view on release of RNA-containing exosomes from the multivesicular bodies for subsequent intercellular targeting. This new alternate pathway for transfer of exRNA between cells has distinct biological and immunological significance, and since most human blood exRNA is not in exosomes may be relevant to evaluation and treatment of diseases.

Free Extracellular miRNA Functionally Targets Cells by Transfecting Exosomes from Their Companion Cells

PubMed Central

Bryniarski, Krzysztof; Ptak, Wlodzimierz; Martin, Emilia; Nazimek, Katarzyna; Szczepanik, Marian; Sanak, Marek; Askenase, Philip W.

2015-01-01

Lymph node and spleen cells of mice doubly immunized by epicutaneous and intravenous hapten application produce a suppressive component that inhibits the action of the effector T cells that mediate contact sensitivity reactions. We recently re-investigated this phenomenon in an immunological system. CD8+ T lymphocyte-derived exosomes transferred suppressive miR-150 to the effector T cells antigen-specifically due to exosome surface coat of antibody light chains made by B1a lymphocytes. Extracellular RNA (exRNA) is protected from plasma RNases by carriage in exosomes or by chaperones. Exosome transfer of functional RNA to target cells is well described, whereas the mechanism of transfer of exRNA free of exosomes remains unclear. In the current study we describe extracellular miR-150, extracted from exosomes, yet still able to mediate antigen-specific suppression. We have determined that this was due to miR-150 association with antibody-coated exosomes produced by B1a cell companions of the effector T cells, which resulted in antigen-specific suppression of their function. Thus functional cell targeting by free exRNA can proceed by transfecting companion cell exosomes that then transfer RNA cargo to the acceptor cells. This contrasts with the classical view on release of RNA-containing exosomes from the multivesicular bodies for subsequent intercellular targeting. This new alternate pathway for transfer of exRNA between cells has distinct biological and immunological significance, and since most human blood exRNA is not in exosomes may be relevant to evaluation and treatment of diseases. PMID:25923429

Adoptive immunotherapy for B-cell malignancies with autologous chimeric antigen receptor modified tumor targeted T cells.

PubMed

Park, Jae H; Brentjens, Renier J

2010-04-01

Chemotherapy-resistant B-cell hematologic malignancies may be cured with allogeneic hematopoietic stem cell transplantation (HSCT), demonstrating the potential susceptibility of these tumors to donor T-cell mediated immune responses. However, high rates of transplant-related morbidity and mortality limit this approach. For this reason, there is an urgent need for less-toxic forms of immune-based cellular therapy to treat these malignancies. Adoptive transfer of autologous T cells genetically modified to express chimeric antigen receptors (CARs) targeted to specific tumor-associated antigens represents an attractive means of overcoming the limitations of conventional HSCT. To this end, investigators have generated CARs targeted to various antigens expressed by B-cell malignancies, optimized the design of these CARs to enhance receptor mediated T cell signaling, and demonstrated significant anti-tumor efficacy of the resulting CAR modified T cells both in vitro and in vivo mouse tumor models. These encouraging preclinical data have justified the translation of this approach to the clinical setting with currently 12 open clinical trials and one completed clinical trial treating various B-cell malignancies utilizing CAR modified T cells targeted to either the CD19 or CD20 B-cell specific antigens.

Vesicle-associated membrane protein 7 (VAMP-7) is essential for target cell killing in a natural killer cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O.; Coughlin, Jason J.

2008-02-15

Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Ourmore » data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24 h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1 ng/mL of granzyme B, compared to 1.5-2.5 {mu}g/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo.« less

Tumor-targeting delivery of herb-based drugs with cell-penetrating/tumor-targeting peptide-modified nanocarriers

PubMed Central

Kebebe, Dereje; Liu, Yuanyuan; Wu, Yumei; Vilakhamxay, Maikhone; Liu, Zhidong; Li, Jiawei

2018-01-01

Cancer has become one of the leading causes of mortality globally. The major challenges of conventional cancer therapy are the failure of most chemotherapeutic agents to accumulate selectively in tumor cells and their severe systemic side effects. In the past three decades, a number of drug delivery approaches have been discovered to overwhelm the obstacles. Among these, nanocarriers have gained much attention for their excellent and efficient drug delivery systems to improve specific tissue/organ/cell targeting. In order to enhance targeting efficiency further and reduce limitations of nanocarriers, nanoparticle surfaces are functionalized with different ligands. Several kinds of ligand-modified nanomedicines have been reported. Cell-penetrating peptides (CPPs) are promising ligands, attracting the attention of researchers due to their efficiency to transport bioactive molecules intracellularly. However, their lack of specificity and in vivo degradation led to the development of newer types of CPP. Currently, activable CPP and tumor-targeting peptide (TTP)-modified nanocarriers have shown dramatically superior cellular specific uptake, cytotoxicity, and tumor growth inhibition. In this review, we discuss recent advances in tumor-targeting strategies using CPPs and their limitations in tumor delivery systems. Special emphasis is given to activable CPPs and TTPs. Finally, we address the application of CPPs and/or TTPs in the delivery of plant-derived chemotherapeutic agents. PMID:29563797

Deep magnetic capture of magnetically loaded cells for spatially targeted therapeutics.

PubMed

Huang, Zheyong; Pei, Ning; Wang, Yanyan; Xie, Xinxing; Sun, Aijun; Shen, Li; Zhang, Shuning; Liu, Xuebo; Zou, Yunzeng; Qian, Juying; Ge, Junbo

2010-03-01

Magnetic targeting has recently demonstrated potential in promoting magnetically loaded cell delivery to target lesion, but its application is limited by magnetic attenuation. For deep magnetic capture of cells for spatial targeting therapeutics, we designed a magnetic pole, in which the magnetic field density can be focused at a distance from the pole. As flowing through a tube served as a model of blood vessels, the magnetically loaded mesenchymal stem cells (MagMSCs) were highly enriched at the site distance from the magnetic pole. The cell capture efficiency was positively influenced by the magnetic flux density, and inversely influenced by the flow velocity, and well-fitted with the deductive value by theoretical considerations. It appeared to us that the spatially-focused property of the magnetic apparatus promises a new deep targeting strategy to promote homing and engraftment for cellular therapy. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

The Clinical Potential of Targeted Nanomedicine: Delivering to Cancer Stem-like Cells

PubMed Central

Kim, Sang-Soo; Rait, Antonina; Rubab, Farwah; Rao, Abhi K; Kiritsy, Michael C; Pirollo, Kathleen F; Wang, Shangzi; Weiner, Louis M; Chang, Esther H

2014-01-01

Cancer stem-like cells (CSCs) have been implicated in recurrence and treatment resistance in many human cancers. Thus, a CSC-targeted drug delivery strategy to eliminate CSCs is a desirable approach for developing a more effective anticancer therapy. We have developed a tumor-targeting nanodelivery platform (scL) for systemic administration of molecular medicines. Following treatment with the scL nanocomplex carrying various payloads, we have observed exquisite tumor-targeting specificity and significant antitumor response with long-term survival benefit in numerous animal models. We hypothesized that this observed efficacy might be attributed, at least in part, to elimination of CSCs. Here, we demonstrate the ability of scL to target both CSCs and differentiated nonstem cancer cells (non-CSCs) in various mouse models including subcutaneous and intracranial xenografts, syngeneic, and chemically induced tumors. We also show that systemic administration of scL carrying the wtp53 gene was able to induce tumor growth inhibition and the death of both CSCs and non-CSCs in subcutaneous colorectal cancer xenografts suggesting that this could be an effective method to reduce cancer recurrence and treatment resistance. This scL nanocomplex is being evaluated in a number of clinical trials where it has been shown to be well tolerated with indications of anticancer activity. PMID:24113515

Controversies in cancer stem cells: targeting embryonic signaling pathways.

PubMed

Takebe, Naoko; Ivy, S Percy

2010-06-15

Selectively targeting cancer stem cells (CSC) or tumor-initiating cells (TIC; from this point onward referred to as CSCs) with novel agents is a rapidly emerging field of oncology. Our knowledge of CSCs and their niche microenvironments remains a nascent field. CSC's critical dependence upon self-renewal makes these regulatory signaling pathways ripe for the development of experimental therapeutic agents. Investigational agents targeting the Notch, Hedgehog, and Wnt pathways are currently in late preclinical development stages, with some early phase 1-2 testing in human subjects. This series of articles will provide an overview and summary of the current state of knowledge of CSCs, their interactive microenvironment, and how they may serve as important targets for antitumor therapies. We also examine the scope and stage of development of early experimental agents that specifically target these highly conserved embryonic signaling pathways. (c) 2010 AACR.

Targeted delivery of doxorubicin into tumor cells by nanostructured lipid carriers conjugated to anti-EGFRvIII monoclonal antibody.

PubMed

Abdolahpour, Saeideh; Toliyat, Tayebeh; Omidfar, Kobra; Modjtahedi, Helmout; Wong, Albert J; Rasaee, Mohammad Javad; Kashanian, Susan; Paknejad, Maliheh

2018-02-01

Epidermal growth factor receptor variant III (EGFRvIII) is the most common variant of the EGF receptor in many human tumors. This variant is tumor specific and highly immunogenic, thus, it can be used as a target for targeted drug delivery toward tumor cells. The major aim of this study was to develop an EGFRvIII-mediated drug delivery system by anti-EGFRvIII monoclonal antibody (MAb) conjugated to doxorubicin (Dox)-loaded nanostructured lipid carriers (NLC) to enhance the targeting specificity and cytotoxic effect of Dox on EGFRvIII-overexpressing cell line. In our study, Dox was chosen as a hydrophobic cytotoxic drug and drug-loaded nanostructured lipid carriers (Dox-NLC) was prepared by solvent emulsification/evaporation method. In order to conjugate anti-EGFRvIII MAb to Dox-NLC, DSPE-PEG2000-NHS (1,2-distearoylphosphatidylethanolamine-polyethylene glycol 2000-NHS) was used as a linker. Physicochemical characteristics of antibody conjugated Dox-NLC (MAb-Dox-NLC), including particle size, zeta potential, entrapment efficiency and in vitro Dox release were investigated. Cytotoxicity of MAb-Dox-NLC against NIH-3T3 and HC2 20d2/c (EGFRvIII-transfected NIH-3T3) cell lines was evaluated. The MAb-Dox-NLC appeared to enhance the cytotoxic activity of targeted NLC against HC2 20d2/c cells. The cellular uptake percentage of targeted NLC by HC2 20d2/c cells was higher than that of NIH-3T3 cells, indicating that EGFRvIII can specifically target HC2 20d2/c cells. In conclusion, anti-EGFRvIII MAb-targeted NLC may be considered as an effective nanocarrier for targeted drug delivery.

MPN estimation of qPCR target sequence recoveries from whole cell calibrator samples.

PubMed

Sivaganesan, Mano; Siefring, Shawn; Varma, Manju; Haugland, Richard A

2011-12-01

DNA extracts from enumerated target organism cells (calibrator samples) have been used for estimating Enterococcus cell equivalent densities in surface waters by a comparative cycle threshold (Ct) qPCR analysis method. To compare surface water Enterococcus density estimates from different studies by this approach, either a consistent source of calibrator cells must be used or the estimates must account for any differences in target sequence recoveries from different sources of calibrator cells. In this report we describe two methods for estimating target sequence recoveries from whole cell calibrator samples based on qPCR analyses of their serially diluted DNA extracts and most probable number (MPN) calculation. The first method employed a traditional MPN calculation approach. The second method employed a Bayesian hierarchical statistical modeling approach and a Monte Carlo Markov Chain (MCMC) simulation method to account for the uncertainty in these estimates associated with different individual samples of the cell preparations, different dilutions of the DNA extracts and different qPCR analytical runs. The two methods were applied to estimate mean target sequence recoveries per cell from two different lots of a commercially available source of enumerated Enterococcus cell preparations. The mean target sequence recovery estimates (and standard errors) per cell from Lot A and B cell preparations by the Bayesian method were 22.73 (3.4) and 11.76 (2.4), respectively, when the data were adjusted for potential false positive results. Means were similar for the traditional MPN approach which cannot comparably assess uncertainty in the estimates. Cell numbers and estimates of recoverable target sequences in calibrator samples prepared from the two cell sources were also used to estimate cell equivalent and target sequence quantities recovered from surface water samples in a comparative Ct method. Our results illustrate the utility of the Bayesian method in accounting for

Water soluble nanoporous nanoparticle for in vivo targeted drug delivery and controlled release in B cells tumor context

NASA Astrophysics Data System (ADS)

de Angelis, F.; Pujia, A.; Falcone, C.; Iaccino, E.; Palmieri, C.; Liberale, C.; Mecarini, F.; Candeloro, P.; Luberto, L.; de Laurentiis, A.; Das, G.; Scala, G.; di Fabrizio, E.

2010-10-01

Multitasking nanoparticles are gaining great attention for smart drug delivery systems. The exploration of the nano-scale opens new concrete opportunities for revealing new properties and undiscovered cell-particle interactions. Here we present a biodegradable nanoporous silicon nanoparticle that can be successfully employed for in vivo targeted drug delivery and sustained release. The bare nanoporous nanocarriers can be accurately designed and fabricated with an effective control of porosity, surface chemistry and particle size, up to a few nm. The proposed nanoparticles exhibit several remarkable features including high payload, biodegradability, no toxicity, and multiple loading in water without the need of additional chemical reagents at room temperature. The targeting strategy is based on phage display technology that was successfully used to discover cell surface binding peptide for murine B lymphoma A20 cell line. The peptide used in combination with the nanoporous nanoparticles allows an efficient in vivo targeting, a sustained release and a sensible therapeutic effect.Multitasking nanoparticles are gaining great attention for smart drug delivery systems. The exploration of the nano-scale opens new concrete opportunities for revealing new properties and undiscovered cell-particle interactions. Here we present a biodegradable nanoporous silicon nanoparticle that can be successfully employed for in vivo targeted drug delivery and sustained release. The bare nanoporous nanocarriers can be accurately designed and fabricated with an effective control of porosity, surface chemistry and particle size, up to a few nm. The proposed nanoparticles exhibit several remarkable features including high payload, biodegradability, no toxicity, and multiple loading in water without the need of additional chemical reagents at room temperature. The targeting strategy is based on phage display technology that was successfully used to discover cell surface binding peptide for

Gene targeting in mosquito cells: a demonstration of 'knockout' technology in extrachromosomal gene arrays

PubMed Central

Eggleston, Paul; Zhao, Yuguang

2001-01-01

Background Gene targeting would offer a number of advantages over current transposon-based strategies for insect transformation. These include freedom from both position effects associated with quasi-random integration and concerns over transgene instability mediated by endogenous transposases, independence from phylogenetic restrictions on transposon mobility and the ability to generate gene knockouts. Results We describe here our initial investigations of gene targeting in the mosquito. The target site was a hygromycin resistance gene, stably maintained as part of an extrachromosomal array. Using a promoter-trap strategy to enrich for targeted events, a neomycin resistance gene was integrated into the target site. This resulted in knockout of hygromycin resistance concurrent with the expression of high levels of neomycin resistance from the resident promoter. PCR amplification of the targeted site generated a product that was specific to the targeted cell line and consistent with precise integration of the neomycin resistance gene into the 5' end of the hygromycin resistance gene. Sequencing of the PCR product and Southern analysis of cellular DNA subsequently confirmed this molecular structure. Conclusions These experiments provide the first demonstration of gene targeting in mosquito tissue and show that mosquito cells possess the necessary machinery to bring about precise integration of exogenous sequences through homologous recombination. Further development of these procedures and their extension to chromosomally located targets hold much promise for the exploitation of gene targeting in a wide range of medically and economically important insect species. PMID:11513755

Liver cell-targeted delivery of therapeutic molecules.

PubMed

Kang, Jeong-Hun; Toita, Riki; Murata, Masaharu

2016-01-01

The liver is the largest internal organ in mammals and is involved in metabolism, detoxification, synthesis of proteins and lipids, secretion of cytokines and growth factors and immune/inflammatory responses. Hepatitis, alcoholic or non-alcoholic liver disease, hepatocellular carcinoma, hepatic veno-occlusive disease, and liver fibrosis and cirrhosis are the most common liver diseases. Safe and efficient delivery of therapeutic molecules (drugs, genes or proteins) into the liver is very important to increase the clinical efficacy of these molecules and to reduce their side effects in other organs. Several liver cell-targeted delivery systems have been developed and tested in vivo or ex vivo/in vitro. In this review, we discuss the literature concerning liver cell-targeted delivery systems, with a particular emphasis on the results of in vivo studies.

Metabolic and structural integrity of magnetic nanoparticle-loaded primary endothelial cells for targeted cell therapy.

PubMed

Orynbayeva, Zulfiya; Sensenig, Richard; Polyak, Boris

2015-05-01

To successfully translate magnetically mediated cell targeting from bench to bedside, there is a need to systematically assess the potential adverse effects of magnetic nanoparticles (MNPs) interacting with 'therapeutic' cells. Here, we examined in detail the effects of internalized polymeric MNPs on primary rat endothelial cells' structural intactness, metabolic integrity and proliferation potential. The intactness of cytoskeleton and organelles was studied by fluorescent confocal microscopy, flow cytometry and high-resolution respirometry. MNP-loaded primary endothelial cells preserve intact cytoskeleton and organelles, maintain normal rate of proliferation, calcium signaling and mitochondria energy metabolism. This study provides supportive evidence that MNPs at doses necessary for targeting did not induce significant adverse effects on structural integrity and functionality of primary endothelial cells - potential cell therapy vectors.

Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in situ targeting of dendritic cells

PubMed Central

Morelli, Adrian E.; Thomson, Angus W.

2014-01-01

Purpose of review Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCreg) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCreg (donor or recipient) and their mode of action, in situ targeting of DCreg, and optimal therapeutic regimens to promote DCreg function. Recent findings Recent studies have defined protocols and mechanisms whereby ex vivo-generated DCreg of donor or recipient origin subvert allogeneic T cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen (Ag) is acquired, processed and presented by autologous DCs, on the stability of DCreg, and on in situ targeting of DC to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCreg in a clinically-relevant non-human primate organ transplant model and production of clinical grade DCreg support early evaluation of DCreg therapy in human graft recipients. Summary We discuss strategies currently used to promote DC tolerogenicity, including DCreg therapy and in situ targeting of DC, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application. PMID:24926700

A 20-Amino Acid Module of Protein Kinase Cϵ Involved in Translocation and Selective Targeting at Cell-Cell Contacts*

PubMed Central

Diouf, Barthélémy; Collazos, Alejandra; Labesse, Gilles; Macari, Françoise; Choquet, Armelle; Clair, Philippe; Gauthier-Rouvière, Cécile; Guérineau, Nathalie C.; Jay, Philippe; Hollande, Frédéric; Joubert, Dominique

2009-01-01

In the pituitary gland, activated protein kinase C (PKC) isoforms accumulate either selectively at the cell-cell contact (α and ϵ) or at the entire plasma membrane (β1 and δ). The molecular mechanisms underlying these various subcellular locations are not known. Here, we demonstrate the existence within PKCϵ of a cell-cell contact targeting sequence (3CTS) that, upon stimulation, is capable of targeting PKCδ, chimerin-α1, and the PKCϵ C1 domain to the cell-cell contact. We show that this selective targeting of PKCϵ is lost upon overexpression of 3CTS fused to a (R-Ahx-R)4 (where Ahx is 6-aminohexanoic acid) vectorization peptide, reflecting a dominant-negative effect of the overexpressed 3CTS on targeting selectivity. 3CTS contains a putative amphipathic α-helix, a 14-3-3-binding site, and the Glu-374 amino acid, involved in targeting selectivity. We show that the integrity of the α-helix is important for translocation but that 14-3-3 is not involved in targeting selectivity. However, PKCϵ translocation is increased when PKCϵ/14-3-3 interaction is abolished, suggesting that phorbol 12-myristate 13-acetate activation may initiate two sets of PKCϵ functions, those depending on 14-3-3 and those depending on translocation to cell-cell contacts. Thus, 3CTS is involved in the modulation of translocation via its 14-3-3-binding site, in cytoplasmic desequestration via the α-helix, and in selective PKCϵ targeting at the cell-cell contact via Glu-374. PMID:19429675

E-selectin liposomal and nanotube-targeted delivery of doxorubicin to circulating tumor cells

PubMed Central

Mitchell, Michael J.; Chen, Christina S.; Ponmudi, Varun; Hughes, Andrew D.; King, Michael R.

2012-01-01

The presence of circulating tumor cells (CTCs) is believed to lead to the formation of secondary tumors via an adhesion cascade involving interaction between adhesion receptors of endothelial cells and ligands on CTCs. Many CTCs express sialylated carbohydrate ligands on their surfaces that adhere to selectin protein found on inflamed endothelial cells. We have investigated the feasibility of using immobilized selectin proteins as a targeting mechanism for CTCs under flow. Herein, targeted liposomal doxorubicin (L-DXR) was functionalized with recombinant human E-selectin (ES) and polyethylene glycol (PEG) to target and kill cancer cells under shear flow, both when immobilized along a microtube device or sheared in a cone-and-plate viscometer in a dilute suspension. Healthy circulating cells such as red blood cells were not targeted by this mechanism and were left to freely circulate, and minimal leukocyte death was observed. Halloysite nanotube (HNT)-coated microtube devices immobilized with nanoscale liposomes significantly enhanced the targeting, capture, and killing of cancer cells. This work demonstrates that E-selectin functionalized L-DXR, sheared in suspension or immobilized onto microtube devices, provides a novel approach to selectively target and deliver chemotherapeutics to CTCs in the bloodstream. PMID:22421423

Targeted organ generation using Mixl1-inducible mouse pluripotent stem cells in blastocyst complementation.

PubMed

Kobayashi, Toshihiro; Kato-Itoh, Megumi; Nakauchi, Hiromitsu

2015-01-15

Generation of functional organs from patients' own cells is one of the ultimate goals of regenerative medicine. As a novel approach to creation of organs from pluripotent stem cells (PSCs), we employed blastocyst complementation in organogenesis-disabled animals and successfully generated PSC-derived pancreas and kidneys. Blastocyst complementation, which exploits the capacity of PSCs to participate in forming chimeras, does not, however, exclude contribution of PSCs to the development of tissues-including neural cells or germ cells-other than those specifically targeted by disabling of organogenesis. This fact provokes ethical controversy if human PSCs are to be used. In this study, we demonstrated that forced expression of Mix-like protein 1 (encoded by Mixl1) can be used to guide contribution of mouse embryonic stem cells to endodermal organs after blastocyst injection. We then succeeded in applying this method to generate functional pancreas in pancreatogenesis-disabled Pdx1 knockout mice using a newly developed tetraploid-based organ-complementation method. These findings hold promise for targeted organ generation from patients' own PSCs in livestock animals.

Concise Review: Cell Surface N-Linked Glycoproteins as Potential Stem Cell Markers and Drug Targets.

PubMed

Boheler, Kenneth R; Gundry, Rebekah L

2017-01-01

Stem cells and their derivatives hold great promise to advance regenerative medicine. Critical to the progression of this field is the identification and utilization of antibody-accessible cell-surface proteins for immunophenotyping and cell sorting-techniques essential for assessment and isolation of defined cell populations with known functional and therapeutic properties. Beyond their utility for cell identification and selection, cell-surface proteins are also major targets for pharmacological intervention. Although comprehensive cell-surface protein maps are highly valuable, they have been difficult to define until recently. In this review, we discuss the application of a contemporary targeted chemoproteomic-based technique for defining the cell-surface proteomes of stem and progenitor cells. In applying this approach to pluripotent stem cells (PSCs), these studies have improved the biological understanding of these cells, led to the enhanced use and development of antibodies suitable for immunophenotyping and sorting, and contributed to the repurposing of existing drugs without the need for high-throughput screening. The utility of this latter approach was first demonstrated with human PSCs (hPSCs) through the identification of small molecules that are selectively toxic to hPSCs and have the potential for eliminating confounding and tumorigenic cells in hPSC-derived progeny destined for research and transplantation. Overall, the cutting-edge technologies reviewed here will accelerate the development of novel cell-surface protein targets for immunophenotyping, new reagents to improve the isolation of therapeutically qualified cells, and pharmacological studies to advance the treatment of intractable diseases amenable to cell-replacement therapies. Stem Cells Translational Medicine 2017;6:131-138. © 2016 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

miR-1271 promotes non-small-cell lung cancer cell proliferation and invasion via targeting HOXA5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yongfang; Xu, Lianhong; Jiang, Lixin, E-mail: jianglx66766@163.com

2015-03-13

MicroRNAs (miRNAs) are short, non-coding RNAs (∼22 nt) that play important roles in the pathogenesis of human diseases by negatively regulating numerous target genes at posttranscriptional level. However, the role of microRNAs in lung cancer, particularly non-small-cell lung cancer (NSCLC), has remained elusive. In this study, two microRNAs, miR-1271 and miR-628, and their predicted target genes were identified differentially expressed in NSCLC by analyzing the miRNA and mRNA expression data from NSCLC tissues and their matching normal controls. miR-1271 and its target gene HOXA5 were selected for further investigation. CCK-8 proliferation assay showed that the cell proliferation was promoted by miR-1271more » in NSCLC cells, while miR-1271 inhibitor could significantly inhibited the proliferation of NSCLC cells. Interestingly, migration and invasion assay indicated that overexpression of miR-1271 could significantly promoted the migration and invasion of NSCLC cells, whereas miR-1271 inhibitor could inhibited both cell migration and invasion of NSCLC cells. Western blot showed that miR-1271 suppressed the protein level of HOXA5, and luciferase assays confirmed that miR-1271 directly bound to the 3'untranslated region of HOXA5. This study indicated indicate that miR-1271 regulates NSCLC cell proliferation and invasion, via the down-regulation of HOXA5. Thus, miR-1271 may represent a potential therapeutic target for NSCLC intervention. - Highlights: • Overexpression of miR-1271 promoted proliferation and invasion of NSCLC cells. • miR-1271 inhibitor inhibited the proliferation and invasion of NSCLC cells. • miR-1271 targets 3′ UTR of HOXA5 in NSCLC cells. • miR-1271 negatively regulates HOXA5 in NSCLC cells.« less

Requirement of the CroRS Two-Component System for Resistance to Cell Wall-Targeting Antimicrobials in Enterococcus faecium.

PubMed

Kellogg, Stephanie L; Little, Jaime L; Hoff, Jessica S; Kristich, Christopher J

2017-05-01

Enterococci are serious opportunistic pathogens that are resistant to many cell wall-targeting antibiotics. The CroRS two-component signaling system responds to antibiotic-mediated cell wall stress and is critical for resistance to cell wall-targeting antibiotics in Enterococcus faecalis Here, we identify and characterize an orthologous two-component system found in Enterococcus faecium that is functionally equivalent to the CroRS system of E. faecalis Deletion of croRS in E. faecium resulted in marked susceptibility to cell wall-targeting agents including cephalosporins and bacitracin, as well as moderate susceptibility to ampicillin and vancomycin. As in E. faecalis , exposure to bacitracin and vancomycin stimulates signaling through the CroRS system in E. faecium Moreover, the CroRS system is critical in E. faecium for enhanced beta-lactam resistance mediated by overexpression of Pbp5. Expression of a Pbp5 variant that confers enhanced beta-lactam resistance cannot overcome the requirement for CroRS function. Thus, the CroRS system is a conserved signaling system that responds to cell wall stress to promote intrinsic resistance to important cell wall-targeting antibiotics in clinically relevant enterococci. Copyright © 2017 American Society for Microbiology.

Requirement of the CroRS Two-Component System for Resistance to Cell Wall-Targeting Antimicrobials in Enterococcus faecium

PubMed Central

Kellogg, Stephanie L.; Little, Jaime L.; Hoff, Jessica S.

2017-01-01

ABSTRACT Enterococci are serious opportunistic pathogens that are resistant to many cell wall-targeting antibiotics. The CroRS two-component signaling system responds to antibiotic-mediated cell wall stress and is critical for resistance to cell wall-targeting antibiotics in Enterococcus faecalis. Here, we identify and characterize an orthologous two-component system found in Enterococcus faecium that is functionally equivalent to the CroRS system of E. faecalis. Deletion of croRS in E. faecium resulted in marked susceptibility to cell wall-targeting agents including cephalosporins and bacitracin, as well as moderate susceptibility to ampicillin and vancomycin. As in E. faecalis, exposure to bacitracin and vancomycin stimulates signaling through the CroRS system in E. faecium. Moreover, the CroRS system is critical in E. faecium for enhanced beta-lactam resistance mediated by overexpression of Pbp5. Expression of a Pbp5 variant that confers enhanced beta-lactam resistance cannot overcome the requirement for CroRS function. Thus, the CroRS system is a conserved signaling system that responds to cell wall stress to promote intrinsic resistance to important cell wall-targeting antibiotics in clinically relevant enterococci. PMID:28223383

Phospho-TCTP as a therapeutic target of dihydroartemisinin for aggressive breast cancer cells

PubMed Central

Lucibello, Maria; Adanti, Sara; Antelmi, Ester; Dezi, Dario; Ciafrè, Stefania; Carcangiu, Maria Luisa; Zonfrillo, Manuela; Nicotera, Giuseppe; Sica, Lorenzo; De Braud, Filippo; Pierimarchi, Pasquale

2015-01-01

Upregulation of Translationally Controlled Tumor Protein (TCTP) is associated with poorly differentiated aggressive tumors, including breast cancer, but the underlying mechanism(s) are still debated. Here, we show that in breast cancer cell lines TCTP is primarily localized in the nucleus, mostly in the phosphorylated form. The effects of Dihydroartemisinin (DHA), an anti-malaria agent that binds TCTP, were tested on breast cancer cells. DHA decreases cell proliferation and induces apoptotic cell death by targeting the phosphorylated form of TCTP. Remarkably, DHA enhances the anti-tumor effects of Doxorubicin in triple negative breast cancer cells resulting in an increased level of apoptosis. DHA also synergizes with Trastuzumab, used to treat HER2/neu positive breast cancers, to induce apoptosis of tumor cells. Finally, we present new clinical data that nuclear phospho-TCTP overexpression in primary breast cancer tissue is associated with high histological grade, increase expression of Ki-67 and with ER-negative breast cancer subtypes. Notably, phospho-TCTP expression levels increase in trastuzumab-resistant breast tumors, suggesting a possible role of phospho-TCTP as a new prognostic marker. In conclusion, the anti-tumor effect of DHA in vitro with conventional chemotherapeutics suggests a novel therapeutic strategy and identifies phospho-TCTP as a new promising target for advanced breast cancer. PMID:25779659

Targeting cancer stem cell-specific markers and/or associated signaling pathways for overcoming cancer drug resistance.

PubMed

Ranji, Peyman; Salmani Kesejini, Tayyebali; Saeedikhoo, Sara; Alizadeh, Ali Mohammad

2016-10-01

Cancer stem cells (CSCs) are a small subpopulation of tumor cells with capabilities of self-renewal, dedifferentiation, tumorigenicity, and inherent chemo-and-radio therapy resistance. Tumor resistance is believed to be caused by CSCs that are intrinsically challenging to common treatments. A number of CSC markers including CD44, CD133, receptor tyrosine kinase, aldehyde dehydrogenases, epithelial cell adhesion molecule/epithelial specific antigen, and ATP-binding cassette subfamily G member 2 have been proved as the useful targets for defining CSC population in solid tumors. Furthermore, targeting CSC markers through new therapeutic strategies will ultimately improve treatments and overcome cancer drug resistance. Therefore, the identification of novel strategies to increase sensitivity of CSC markers has major clinical implications. This review will focus on the innovative treatment methods such as nano-, immuno-, gene-, and chemotherapy approaches for targeting CSC-specific markers and/or their associated signaling pathways.

Surrogate target cells expressing surface anti-idiotype antibody for the clinical evaluation of an internalizing CD22-specific antibody.

PubMed

Leung, Shui-On; Gao, Kai; Wang, Guang Yu; Cheung, Benny Ka-Wa; Lee, Kwan-Yeung; Zhao, Qi; Cheung, Wing-Tai; Wang, Jun Zhi

2015-01-01

SM03, a chimeric antibody that targets the B-cell restricted antigen CD22, is currently being clinically evaluated for the treatment of lymphomas and other autoimmune diseases in China. SM03 binding to surface CD22 leads to rapid internalization, making the development of an appropriate cell-based bioassay for monitoring changes in SM03 bioactivities during production, purification, storage, and clinical trials difficult. We report herein the development of an anti-idiotype antibody against SM03. Apart from its being used as a surrogate antigen for monitoring SM03 binding affinities, the anti-idiotype antibody was engineered to express as fusion proteins on cell surfaces in a non-internalizing manner, and the engineered cells were used as novel "surrogate target cells" for SM03. SM03-induced complement-mediated cytotoxicity (CMC) against these "surrogate target cells" proved to be an effective bioassay for monitoring changes in Fc functions, including those resulting from minor structural modifications borne within the Fc-appended carbohydrates. The approach can be generally applied for antibodies that target rapidly internalizing or non-surface bound antigens. The combined use of the anti-idiotype antibody and the surrogate target cells could help evaluate clinical parameters associated with safety and efficacies, and possibly the mechanisms of action of SM03.

A perspective on B-cell-targeting therapy for SLE.

PubMed

Looney, R John; Anolik, Jennifer; Sanz, Inaki

2010-02-01

In recent years, large controlled trials have tested several new agents for systemic lupus erythematosus (SLE). Unfortunately, none of these trials has met its primary outcome. This does not mean progress has not been made. In fact, a great deal has been learned about doing clinical trials in lupus and about the biological and clinical effects of the drugs being tested. Many of these drugs were designed to target B cells directly, e.g., rituximab, belimumab, epratuzumab, and transmembrane activator and calcium modulator and cyclophilin ligand interactor-immunoglobulin (TACI-Ig). The enthusiasm for targeting B cells derives from substantial evidence showing the critical role of B cells in murine models of SLE, as well promising results from multiple open trials with rituximab, a chimeric anti-CD20 monoclonal antibody that specifically depletes B cells (Martin and Chan in Immunity 20(5):517-527, 2004; Sobel et al. in J Exp Med 173:1441-1449, 1991; Silverman and Weisman in Arthritis Rheum 48:1484-1492, 2003; Silverman in Arthritis Rheum 52(4):1342, 2005; Shlomchik et al. in Nat Rev Immunol 1:147-153, 2001; Looney et al. in Arthritis Rheum 50:2580-2589, 2004; Lu et al. in Arthritis Rheum 61(4):482-487, 2009; Saito et al. in Lupus 12(10):798-800, 2003; van Vollenhoven et al. in Scand J Rheumatol 33(6):423-427, 2004; Sfikakis et al. Arthritis Rheum 52(2):501-513, 2005). Why have the controlled trials of B-cell-targeting therapies failed to demonstrate efficacy? Were there flaws in design or execution of these trials? Or, were promising animal studies and open trials misleading, as so often happens? This perspective discusses the current state of B-cell-targeting therapies for human lupus and the future development of these therapies.

Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neo-Vascularization

PubMed Central

Dubrac, Alexandre; Genet, Gael; Ola, Roxana; Zhang, Feng; Pibouin-Fragner, Laurence; Han, Jinah; Zhang, Jiasheng; Thomas, Jean-Léon; Chedotal, Alain; Schwartz, Martin A.; Eichmann, Anne

2015-01-01

Background Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. Methods and Results Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2 and VEGF induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, as well as pathological ocular neovascularization and wound healing. Conclusions These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2 and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis. PMID:26659946

VEGFR2-targeted fusion antibody improved NK cell-mediated immunosurveillance against K562 cells.

PubMed

Ren, Xueyan; Xie, Wei; Wang, Youfu; Xu, Menghuai; Liu, Fang; Tang, Mingying; Li, Chenchen; Wang, Min; Zhang, Juan

2016-08-01

MHC class I polypeptide-related sequence A (MICA), which is normally expressed on cancer cells, activates NK cells via NK group 2-member D pathway. However, some cancer cells escape NK-mediated immune surveillance by shedding membrane MICA causing immune suppression. To address this issue, we designed an antibody-MICA fusion targeting tumor-specific antigen (vascular endothelial growth factor receptor 2, VEGFR2) based on our patented antibody (mAb04) against VEGFR2. In vitro results demonstrate that the fusion antibody retains both the antineoplastic and the immunomodulatory activity of mAb04. Further, we revealed that it enhanced NK-mediated immunosurveillance against K562 cells through increasing degranulation and cytokine production of NK cells. The overall data suggest our new fusion protein provides a promising approach for cancer-targeted immunotherapy and has prospects for potential application of chronic myeloid leukemia.

Catechol polymers for pH-responsive, targeted drug delivery to cancer cells.

PubMed

Su, Jing; Chen, Feng; Cryns, Vincent L; Messersmith, Phillip B

2011-08-10

A novel cell-targeting, pH-sensitive polymeric carrier was employed in this study for delivery of the anticancer drug bortezomib (BTZ) to cancer cells. Our strategy is based on facile conjugation of BTZ to catechol-containing polymeric carriers that are designed to be taken up selectively by cancer cells through cell surface receptor-mediated mechanisms. The polymer used as a building block in this study was poly(ethylene glycol), which was chosen for its ability to reduce nonspecific interactions with proteins and cells. The catechol moiety was exploited for its ability to bind and release borate-containing therapeutics such as BTZ in a pH-dependent manner. In acidic environments, such as in cancer tissue or the subcellular endosome, BTZ dissociates from the polymer-bound catechol groups to liberate the free drug, which inhibits proteasome function. A cancer-cell-targeting ligand, biotin, was presented on the polymer carriers to facilitate targeted entry of drug-loaded polymer carriers into cancer cells. Our study demonstrated that the cancer-targeting drug-polymer conjugates dramatically enhanced cellular uptake, proteasome inhibition, and cytotoxicity toward breast carcinoma cells in comparison with nontargeting drug-polymer conjugates. The pH-sensitive catechol-boronate binding mechanism provides a chemoselective approach for controlling the release of BTZ in targeted cancer cells, establishing a concept that may be applied in the future toward other boronic acid-containing therapeutics to treat a broad range of diseases. © 2011 American Chemical Society

Targeting stromal glutamine synthetase in tumors disrupts tumor microenvironment-regulated cancer cell growth

USDA-ARS?s Scientific Manuscript database

Reactive stromal cells are an integral part of tumor microenvironment (TME) and interact with cancer cells to regulate their growth. Although targeting stromal cells could be a viable therapy to regulate the communication between TME and cancer cells, identification of stromal targets that make canc...

Targeting HIV Reservoir in Infected CD4 T Cells by Dual-Affinity Re-targeting Molecules (DARTs) that Bind HIV Envelope and Recruit Cytotoxic T Cells

PubMed Central

Sloan, Derek D.; Lam, Chia-Ying Kao; Irrinki, Alivelu; Liu, Liqin; Tsai, Angela; Pace, Craig S.; Kaur, Jasmine; Murry, Jeffrey P.; Balakrishnan, Mini; Moore, Paul A.; Johnson, Syd; Nordstrom, Jeffrey L.; Cihlar, Tomas; Koenig, Scott

2015-01-01

HIV reservoirs and production of viral antigens are not eliminated in chronically infected participants treated with combination antiretroviral therapy (cART). Novel therapeutic strategies aiming at viral reservoir elimination are needed to address chronic immune dysfunction and non-AIDS morbidities that exist despite effective cART. The HIV envelope protein (Env) is emerging as a highly specific viral target for therapeutic elimination of the persistent HIV-infected reservoirs via antibody-mediated cell killing. Dual-Affinity Re-Targeting (DART) molecules exhibit a distinct mechanism of action via binding the cell surface target antigen and simultaneously engaging CD3 on cytotoxic T lymphocytes (CTLs). We designed and evaluated Env-specific DARTs (HIVxCD3 DARTs) derived from known antibodies recognizing diverse Env epitopes with or without broadly neutralizing activity. HIVxCD3 DARTs derived from PGT121, PGT145, A32, and 7B2, but not VRC01 or 10E8 antibodies, mediated potent CTL-dependent killing of quiescent primary CD4 T cells infected with diverse HIV isolates. Similar killing activity was also observed with DARTs structurally modified for in vivo half-life extension. In an ex vivo model using cells isolated from HIV-infected participants on cART, combinations of the most potent HIVxCD3 DARTs reduced HIV expression both in quiescent and activated peripheral blood mononuclear cell cultures isolated from HIV-infected participants on suppressive cART. Importantly, HIVxCD3 DARTs did not induce cell-to-cell virus spread in resting or activated CD4 T cell cultures. Collectively, these results provide support for further development of HIVxCD3 DARTs as a promising therapeutic strategy for targeting HIV reservoirs. PMID:26539983

Circulating and disseminated tumor cells: diagnostic tools and therapeutic targets in motion

PubMed Central

Lin, Peter P.; Gires, Olivier

2017-01-01

Enumeration of circulating tumor cells (CTCs) in peripheral blood with the gold standard CellSearchTM has proven prognostic value for tumor recurrence and progression of metastatic disease. Therefore, the further molecular characterization of isolated CTCs might have clinical relevance as liquid biopsy for therapeutic decision-making and to monitor disease progression. The direct analysis of systemic cancer appears particularly important in view of the known disparity in expression of therapeutic targets as well as epithelial-to-mesenchymal transition (EMT)-based heterogeneity between primary and systemic tumor cells, which all substantially complicate monitoring and therapeutic targeting at present. Since CTCs are the potential precursor cells of metastasis, their in-depth molecular profiling should also provide a useful resource for target discovery. The present review will discuss the use of systemically spread cancer cells as liquid biopsy and focus on potential target antigens. PMID:27683128

Targeted delivery of celastrol to mesangial cells is effective against mesangioproliferative glomerulonephritis.

PubMed

Guo, Ling; Luo, Shi; Du, Zhengwu; Zhou, Meiling; Li, Peiwen; Fu, Yao; Sun, Xun; Huang, Yuan; Zhang, Zhirong

2017-10-12

Mesangial cells-mediated glomerulonephritis is a frequent cause of end-stage renal disease. Here, we show that celastrol is effective in treating both reversible and irreversible mesangioproliferative glomerulonephritis in rat models, but find that its off-target distributions cause severe systemic toxicity. We thus target celastrol to mesangial cells using albumin nanoparticles. Celastrol-albumin nanoparticles crosses fenestrated endothelium and accumulates in mesangial cells, alleviating proteinuria, inflammation, glomerular hypercellularity, and excessive extracellular matrix deposition in rat anti-Thy1.1 nephritis models. Celastrol-albumin nanoparticles presents lower drug accumulation than free celastrol in off-target organs and tissues, thereby minimizing celastrol-related systemic toxicity. Celastrol-albumin nanoparticles thus represents a promising treatment option for mesangioproliferative glomerulonephritis and similar glomerular diseases.Mesangial cell-mediated glomerulonephritis is a frequent cause of kidney disease. Here the authors show that celastrol loaded in albumin nanoparticles efficiently targets mesangial cells, and is effective in rat models.

Off to the Organelles - Killing Cancer Cells with Targeted Gold Nanoparticles

PubMed Central

Kodiha, Mohamed; Wang, Yi Meng; Hutter, Eliza; Maysinger, Dusica; Stochaj, Ursula

2015-01-01

Gold nanoparticles (AuNPs) are excellent tools for cancer cell imaging and basic research. However, they have yet to reach their full potential in the clinic. At present, we are only beginning to understand the molecular mechanisms that underlie the biological effects of AuNPs, including the structural and functional changes of cancer cells. This knowledge is critical for two aspects of nanomedicine. First, it will define the AuNP-induced events at the subcellular and molecular level, thereby possibly identifying new targets for cancer treatment. Second, it could provide new strategies to improve AuNP-dependent cancer diagnosis and treatment. Our review summarizes the impact of AuNPs on selected subcellular organelles that are relevant to cancer therapy. We focus on the nucleus, its subcompartments, and mitochondria, because they are intimately linked to cancer cell survival, growth, proliferation and death. While non-targeted AuNPs can damage tumor cells, concentrating AuNPs in particular subcellular locations will likely improve tumor cell killing. Thus, it will increase cancer cell damage by photothermal ablation, mechanical injury or localized drug delivery. This concept is promising, but AuNPs have to overcome multiple hurdles to perform these tasks. AuNP size, morphology and surface modification are critical parameters for their delivery to organelles. Recent strategies explored all of these variables, and surface functionalization has become crucial to concentrate AuNPs in subcellular compartments. Here, we highlight the use of AuNPs to damage cancer cells and their organelles. We discuss current limitations of AuNP-based cancer research and conclude with future directions for AuNP-dependent cancer treatment. PMID:25699096

Identification and validation nucleolin as a target of curcumol in nasopharyngeal carcinoma cells.

PubMed

Wang, Juan; Wu, Jiacai; Li, Xumei; Liu, Haowei; Qin, Jianli; Bai, Zhun; Chi, Bixia; Chen, Xu

2018-06-30

Identification of the specific protein target(s) of a drug is a critical step in unraveling its mechanisms of action (MOA) in many natural products. Curcumol, isolated from well known Chinese medicinal plant Curcuma zedoary, has been shown to possess multiple biological activities. It can inhibit nasopharyngeal carcinoma (NPC) proliferation and induce apoptosis, but its target protein(s) in NPC cells remains unclear. In this study, we employed a mass spectrometry-based chemical proteomics approach reveal the possible protein targets of curcumol in NPC cells. Cellular thermal shift assay (CETSA), molecular docking and cell-based assay was used to validate the binding interactions. Chemical proteomics capturing uncovered that NCL is a target of curcumol in NPC cells, Molecular docking showed that curcumol bound to NCL with an -7.8 kcal/mol binding free energy. Cell function analysis found that curcumol's treatment leads to a degradation of NCL in NPC cells, and it showed slight effects on NP69 cells. In conclusion, our results providing evidences that NCL is a target protein of curcumol. We revealed that the anti-cancer effects of curcumol in NPC cells are mediated, at least in part, by NCL inhibition. Many natural products showed high bioactivity, while their mechanisms of action (MOA) are very poor or completely missed. Understanding the MOA of natural drugs can thoroughly exploit their therapeutic potential and minimize their adverse side effects. Identification of the specific protein target(s) of a drug is a critical step in unraveling its MOA. Compound-centric chemical proteomics is a classic chemical proteomics approach which integrates chemical synthesis with cell biology and mass spectrometry (MS) to identify protein targets of natural products determine the drug mechanism of action, describe its toxicity, and figure out the possible cause of off-target. It is an affinity-based chemical proteomics method to identify small molecule-protein interactions

Viral Capsid DNA Aptamer Conjugates as Multivalent Cell Targeting Vehicles

PubMed Central

Tong, Gary J.; Hsiao, Sonny C.; Carrico, Zachary M.; Francis, Matthew B.

2009-01-01

Nucleic acid aptamers offer significant potential as convenient and evolvable targeting groups for drug delivery. To attach them to the surface of a genome-free viral capsid carrier, an efficient oxidative coupling strategy has been developed. The method involves the periodate-mediated reaction of phenylene diamine substituted oligonucleotides with aniline groups installed on the outer surface of the capsid shells. Up to 60 DNA strands can be attached to each viral capsid with no apparent loss of base-pairing capabilities or protein stability. The ability of the capsids to bind specific cellular targets was demonstrated through the attachment of a 41-nucleotide sequence that targets a tyrosine kinase receptor on Jurkat T cells. After the installation of a fluorescent dye on the capsid interior, capsids bearing the cell-targeting sequence showed significant levels of binding to the cells relative to control samples. Colocalization experiments using confocal microscopy indicated that the capsids were endocytosed and trafficked to lysosomes for degradation. These observations suggest that aptamer-labeled capsids could be used for the targeted drug delivery of acid-labile prodrugs that would be preferentially released upon lysosomal acidification. PMID:19603808

miRNA-1297 induces cell proliferation by targeting phosphatase and tensin homolog in testicular germ cell tumor cells.

PubMed

Yang, Nian-Qin; Zhang, Jian; Tang, Qun-Ye; Guo, Jian-Ming; Wang, Guo-Min

2014-01-01

To investigate the role of miR-1297 and the tumor suppressor gene PTEN in cell proliferation of testicular germ cell tumors (TGCT). MTT assays were used to test the effect of miR-1297 on proliferation of the NCCIT testicular germ cell tumor cell line. In NCCIT cells, the expression of PTEN was assessed by Western blotting further. In order to confirm target association between miR-1297 and 3'-UTR of PTEN, a luciferase reporter activity assay was employed. Moreover, roles of PTEN in proliferation of NCCIT cells were evaluated by transfection of PTEN siRNA. Proliferation of NCCIT cells was promoted by miR-1297 in a concentration-dependent manner. In addition, miR-1297 could bind to the 3'-UTR of PTEN based on luciferase reporter activity assay, and reduced expression of PTEN at protein level was found. Proliferation of NCCIT cells was significantly enhanced after knockdown of PTEN by siRNA. miR-1297 as a potential oncogene could induce cell proliferation by targeting PTEN in NCCIT cells.

Treatment Options for Plasma Cell Neoplasms (Including Multiple Myeloma)

MedlinePlus

... Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key Points ...

Treatment Option Overview (Plasma Cell Neoplasms Including Multiple Myeloma)

MedlinePlus

... Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key Points ...

TargetLink, a new method for identifying the endogenous target set of a specific microRNA in intact living cells.

PubMed

Xu, Yan; Chen, Yan; Li, Daliang; Liu, Qing; Xuan, Zhenyu; Li, Wen-Hong

2017-02-01

MicroRNAs are small non-coding RNAs acting as posttranscriptional repressors of gene expression. Identifying mRNA targets of a given miRNA remains an outstanding challenge in the field. We have developed a new experimental approach, TargetLink, that applied locked nucleic acid (LNA) as the affinity probe to enrich target genes of a specific microRNA in intact cells. TargetLink also consists a rigorous and systematic data analysis pipeline to identify target genes by comparing LNA-enriched sequences between experimental and control samples. Using miR-21 as a test microRNA, we identified 12 target genes of miR-21 in a human colorectal cancer cell by this approach. The majority of the identified targets interacted with miR-21 via imperfect seed pairing. Target validation confirmed that miR-21 repressed the expression of the identified targets. The cellular abundance of the identified miR-21 target transcripts varied over a wide range, with some targets expressed at a rather low level, confirming that both abundant and rare transcripts are susceptible to regulation by microRNAs, and that TargetLink is an efficient approach for identifying the target set of a specific microRNA in intact cells. C20orf111, one of the novel targets identified by TargetLink, was found to reside in the nuclear speckle and to be reliably repressed by miR-21 through the interaction at its coding sequence.

Cas9-mediated targeting of viral RNA in eukaryotic cells.

PubMed

Price, Aryn A; Sampson, Timothy R; Ratner, Hannah K; Grakoui, Arash; Weiss, David S

2015-05-12

Clustered, regularly interspaced, short palindromic repeats-CRISPR associated (CRISPR-Cas) systems are prokaryotic RNA-directed endonuclease machineries that act as an adaptive immune system against foreign genetic elements. Using small CRISPR RNAs that provide specificity, Cas proteins recognize and degrade nucleic acids. Our previous work demonstrated that the Cas9 endonuclease from Francisella novicida (FnCas9) is capable of targeting endogenous bacterial RNA. Here, we show that FnCas9 can be directed by an engineered RNA-targeting guide RNA to target and inhibit a human +ssRNA virus, hepatitis C virus, within eukaryotic cells. This work reveals a versatile and portable RNA-targeting system that can effectively function in eukaryotic cells and be programmed as an antiviral defense.

Cas9-mediated targeting of viral RNA in eukaryotic cells

PubMed Central

Price, Aryn A.; Sampson, Timothy R.; Ratner, Hannah K.; Grakoui, Arash; Weiss, David S.

2015-01-01

Clustered, regularly interspaced, short palindromic repeats–CRISPR associated (CRISPR-Cas) systems are prokaryotic RNA-directed endonuclease machineries that act as an adaptive immune system against foreign genetic elements. Using small CRISPR RNAs that provide specificity, Cas proteins recognize and degrade nucleic acids. Our previous work demonstrated that the Cas9 endonuclease from Francisella novicida (FnCas9) is capable of targeting endogenous bacterial RNA. Here, we show that FnCas9 can be directed by an engineered RNA-targeting guide RNA to target and inhibit a human +ssRNA virus, hepatitis C virus, within eukaryotic cells. This work reveals a versatile and portable RNA-targeting system that can effectively function in eukaryotic cells and be programmed as an antiviral defense. PMID:25918406

[Study on the hepatocytic cell targetability of liposomes].

PubMed

Hou, Xin-pu; Wang, Li; Wang, Xiang-tao; Li, Sha

2003-02-01

To target for hepatocytic cell, liposomes was modified by special ligand. Sterically stabilized liposomes (SSL) was conjugated with asialofeticin (AF), the ligand of asialoglycoprotein receptor (ASGP-R) of hepatocyte. ASGP-R-BLM is the ASGP-R reconstructed on bilayer lipid membrane (BLM). The recognition reaction between AF-SSL and ASGP-R-BLM can be monitored by the varieties of membrane electrical parameters. The targetability of AF-SSL mediated to hepatocyte was detected by radioisotopic labeled in vitro and in vivo. The therapeutic effect of antihepatocarcinoma was observed also. The lifetime of ASGP-R-BLM decreased with the added amount of AF-SSL. It was demonstrated that there was recognition reaction between AF-SSL and ASGP-R-BLM. The combination of AF-SSL with hepatocyte was significantly higher than that of SSL without AF-modified in vitro and in vivo. The survival time of rat for AF-SSL carriered ADM (adriamycin) group was much longer and the toxicities on heart, kidney and lung were lower than those SSL carried ADM group. It is possible to actively target the cell with specific receptor by ligand modified liposomes. The result prvide scientific basis of hepatocyte targeted liposomes.

Selective in vivo metabolic cell-labeling-mediated cancer targeting

PubMed Central

Wang, Hua; Wang, Ruibo; Cai, Kaimin; He, Hua; Liu, Yang; Yen, Jonathan; Wang, Zhiyu; Xu, Ming; Sun, Yiwen; Zhou, Xin; Yin, Qian; Tang, Li; Dobrucki, Iwona T; Dobrucki, Lawrence W; Chaney, Eric J; Boppart, Stephen A; Fan, Timothy M; Lezmi, Stéphane; Chen, Xuesi; Yin, Lichen; Cheng, Jianjun

2017-01-01

Distinguishing cancer cells from normal cells through surface receptors is vital for cancer diagnosis and targeted therapy. Metabolic glycoengineering of unnatural sugars provides a powerful tool to manually introduce chemical receptors onto the cell surface; however, cancer-selective labeling still remains a great challenge. Herein we report the design of sugars that can selectively label cancer cells both in vitro and in vivo. Specifically, we inhibit the cell-labeling activity of tetraacetyl-N-azidoacetylmannosamine (Ac4ManAz) by converting its anomeric acetyl group to a caged ether bond that can be selectively cleaved by cancer-overexpressed enzymes and thus enables the overexpression of azido groups on the surface of cancer cells. Histone deacetylase and cathepsin L-responsive acetylated azidomannosamine, one such enzymatically activatable Ac4ManAz analog developed, mediated cancer-selective labeling in vivo, which enhanced tumor accumulation of a dibenzocyclooctyne–doxorubicin conjugate via click chemistry and enabled targeted therapy against LS174T colon cancer, MDA-MB-231 triple-negative breast cancer and 4T1 metastatic breast cancer in mice. PMID:28192414

Modified Cross-Linking, Ligation, and Sequencing of Hybrids (qCLASH) Identifies Kaposi's Sarcoma-Associated Herpesvirus MicroRNA Targets in Endothelial Cells.

PubMed

Gay, Lauren A; Sethuraman, Sunantha; Thomas, Merin; Turner, Peter C; Renne, Rolf

2018-04-15

Kaposi's sarcoma (KS) tumors are derived from endothelial cells and express Kaposi's sarcoma-associated herpesvirus (KSHV) microRNAs (miRNAs). Although miRNA targets have been identified in B cell lymphoma-derived cells and epithelial cells, little has been done to characterize the KSHV miRNA targetome in endothelial cells. A recent innovation in the identification of miRNA targetomes, cross-linking, ligation, and sequencing of hybrids (CLASH), unambiguously identifies miRNAs and their targets by ligating the two species while both species are still bound within the RNA-induced silencing complex (RISC). We developed a streamlined quick CLASH (qCLASH) protocol that requires a lower cell input than the original method and therefore has the potential to be used on patient biopsy samples. Additionally, we developed a fast-growing, KSHV-negative endothelial cell line derived from telomerase-immortalized vein endothelial long-term culture (TIVE-LTC) cells. qCLASH was performed on uninfected cells and cells infected with either wild-type KSHV or a mutant virus lacking miR-K12-11/11*. More than 1,400 cellular targets of KSHV miRNAs were identified. Many of the targets identified by qCLASH lacked a canonical seed sequence match. Additionally, most target regions in mRNAs originated from the coding DNA sequence (CDS) rather than the 3' untranslated region (UTR). This set of genes includes some that were previously identified in B cells and some new genes that warrant further study. Pathway analysis of endothelial cell targets showed enrichment in cell cycle control, apoptosis, and glycolysis pathways, among others. Characterization of these new targets and the functional consequences of their repression will be important in furthering our understanding of the role of KSHV miRNAs in oncogenesis. IMPORTANCE KS lesions consist of endothelial cells latently infected with KSHV. Cells that make up these lesions express KSHV miRNAs. Identification of the targets of KSHV miRNAs will

Identification of Novel Targets for Lung Cancer Therapy Using an Induced Pluripotent Stem Cell Model.

PubMed

Shukla, Vivek; Rao, Mahadev; Zhang, Hongen; Beers, Jeanette; Wangsa, Darawalee; Wangsa, Danny; Buishand, Floryne O; Wang, Yonghong; Yu, Zhiya; Stevenson, Holly; Reardon, Emily; McLoughlin, Kaitlin C; Kaufman, Andrew; Payabyab, Eden; Hong, Julie A; Zhang, Mary; Davis, Sean R; Edelman, Daniel C; Chen, Guokai; Miettinen, Markku; Restifo, Nicholas; Ried, Thomas; Meltzer, Paul S; Schrump, David S

2018-04-01

Despite extensive studies, the genetic and epigenetic mechanisms that mediate initiation and progression of lung cancers have not been fully elucidated. Previously, we have demonstrated that via complementary mechanisms, including DNA methylation, polycomb repressive complexes, and noncoding RNAs, cigarette smoke induces stem-like phenotypes that coincide with progression to malignancy in normal respiratory epithelia as well as enhanced growth and metastatic potential of lung cancer cells. To further investigate epigenetic mechanisms contributing to stemness/pluripotency in lung cancers and potentially identify novel therapeutic targets in these malignancies, induced pluripotent stem cells were generated from normal human small airway epithelial cells. Lung induced pluripotent stem cells were generated by lentiviral transduction of small airway epithelial cells of OSKM (Yamanaka) factors (octamer-binding transcription factor 4 [Oct4], sex-determining region Y box 2 [SOX2], Kruppel-like factor 4 [KLF4], and MYC proto-oncogene, bHLH transcription factor [MYC]). Western blot, real-time polymerase chain reaction, and chromatin immunoprecipitation sequencing analysis were performed. The lung induced pluripotent stem cells exhibited hallmarks of pluripotency, including morphology, surface antigen and stem cell gene expression, in vitro proliferation, and teratoma formation. In addition, lung induced pluripotent stem cells exhibited no chromosomal aberrations, complete silencing of reprogramming transgenes, genomic hypermethylation, upregulation of genes encoding components of polycomb repressive complex 2, hypermethylation of stem cell polycomb targets, and modulation of more than 15,000 other genes relative to parental small airway epithelial cells. Additional sex combs like-3 (ASXL3), encoding a polycomb repressive complex 2-associated protein not previously described in reprogrammed cells, was markedly upregulated in lung induced pluripotent stem cell as well as human

Novel therapeutic Strategies for Targeting Liver Cancer Stem Cells

PubMed Central

Oishi, Naoki; Wang, Xin Wei

2011-01-01

The cancer stem cell (CSC) hypothesis was first proposed over 40 years ago. Advances in CSC isolation were first achieved in hematological malignancies, with the first CSC demonstrated in acute myeloid leukemia. However, using similar strategies and technologies, and taking advantage of available surface markers, CSCs have been more recently demonstrated in a growing range of epithelial and other solid organ malignancies, suggesting that the majority of malignancies are dependent on such a compartment. Primary liver cancer consists predominantly of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). It is believed that hepatic progenitor cells (HPCs) could be the origin of some HCCs and ICCs. Furthermore, stem cell activators such as Wnt/β-catenin, TGF-β, Notch and Hedgehog signaling pathways also expedite tumorigenesis, and these pathways could serve as molecular targets to assist in designing cancer prevention strategies. Recent studies indicate that additional factors such as EpCAM, Lin28 or miR-181 may also contribute to HCC progression by targeting HCC CSCs. Various therapeutic drugs that directly modulate CSCs have been examined in vivo and in vitro. However, CSCs clearly have a complex pathogenesis, with a considerable crosstalk and redundancy in signaling pathways, and hence targeting single molecules or pathways may have a limited benefit for treatment. Many of the key signaling molecules are shared by both CSCs and normal stem cells, which add further challenges for designing molecularly targeted strategies specific to CSCs but sparing normal stem cells to avoid side effects. In addition to the direct control of CSCs, many other factors that are needed for the maintenance of CSCs, such as angiogenesis, vasculogenesis, invasion and migration, hypoxia, immune evasion, multiple drug resistance, and radioresistance, should be taken into consideration when designing therapeutic strategies for HCC. Here we provide a brief review of

AXL is a logical molecular target in head and neck squamous cell carcinoma

PubMed Central

Brand, Toni M.; Iida, Mari; Stein, Andrew P.; Corrigan, Kelsey L.; Braverman, Cara M.; Coan, John; Pearson, Hannah E.; Bahrar, Harsh; Fowler, Tyler L.; Bednarz, Bryan P.; Saha, Sandeep; Yang, David; Gill, Parkash S.; Lingen, Mark W.; Saloura, Vassiliki; Villaflor, Victoria M.; Salgia, Ravi; Kimple, Randall J.; Wheeler, Deric L.

2016-01-01

Purpose Head and neck squamous cell carcinoma (HNSCC) represents the eighth most common malignancy worldwide. Standard of care treatments for HNSCC patients include surgery, radiation and chemotherapy. Additionally, the anti-epidermal growth factor receptor (EGFR) monoclonal antibody cetuximab is often used in combination with these treatment modalities. Despite clinical success with these therapeutics, HNSCC remains a difficult to treat malignancy. Thus, identification of new molecular targets is critical. Experimental Design In the current study, the receptor tyrosine kinase AXL was investigated as a molecular target in HNSCC using established cell lines, HNSCC patient derived xenografts (PDXs), and human tumors. HNSCC dependency on AXL was evaluated with both anti-AXL siRNAs and the small molecule AXL inhibitor R428. Furthermore, AXL inhibition was evaluated with standard of care treatment regimes used in HNSCC. Results AXL was found to be highly overexpressed in several models of HNSCC, where AXL was significantly associated with higher pathologic grade, presence of distant metastases and shorter relapse free survival in patients with HNSCC. Further investigations indicated that HNSCC cells were reliant on AXL for cellular proliferation, migration, and invasion. Additionally, targeting AXL increased HNSCC cell line sensitivity to chemotherapy, cetuximab, and radiation. Moreover, radiation resistant HNSCC cell line xenografts and PDXs expressed elevated levels of both total and activated AXL, indicating a role for AXL in radiation resistance. Conclusion Collectively, this study provides evidence for the role of AXL in HNSCC pathogenesis and supports further pre-clinical and clinical evaluation of anti-AXL therapeutics for the treatment of patients with HNSCC. PMID:25767293

Targeting RAS-driven human cancer cells with antibodies to upregulated and essential cell-surface proteins.

PubMed

Martinko, Alexander J; Truillet, Charles; Julien, Olivier; Diaz, Juan E; Horlbeck, Max A; Whiteley, Gordon; Blonder, Josip; Weissman, Jonathan S; Bandyopadhyay, Sourav; Evans, Michael J; Wells, James A

2018-01-23

While there have been tremendous efforts to target oncogenic RAS signaling from inside the cell, little effort has focused on the cell-surface. Here, we used quantitative surface proteomics to reveal a signature of proteins that are upregulated on cells transformed with KRAS G12V , and driven by MAPK pathway signaling. We next generated a toolkit of recombinant antibodies to seven of these RAS-induced proteins. We found that five of these proteins are broadly distributed on cancer cell lines harboring RAS mutations. In parallel, a cell-surface CRISPRi screen identified integrin and Wnt signaling proteins as critical to RAS-transformed cells. We show that antibodies targeting CDCP1, a protein common to our proteomics and CRISPRi datasets, can be leveraged to deliver cytotoxic and immunotherapeutic payloads to RAS-transformed cancer cells and report for RAS signaling status in vivo. Taken together, this work presents a technological platform for attacking RAS from outside the cell. © 2018, Martinko et al.

Bypassing Protein Corona Issue on Active Targeting: Zwitterionic Coatings Dictate Specific Interactions of Targeting Moieties and Cell Receptors.

PubMed

Safavi-Sohi, Reihaneh; Maghari, Shokoofeh; Raoufi, Mohammad; Jalali, Seyed Amir; Hajipour, Mohammad J; Ghassempour, Alireza; Mahmoudi, Morteza

2016-09-07

Surface functionalization strategies for targeting nanoparticles (NP) to specific organs, cells, or organelles, is the foundation for new applications of nanomedicine to drug delivery and biomedical imaging. Interaction of NPs with biological media leads to the formation of a biomolecular layer at the surface of NPs so-called as "protein corona". This corona layer can shield active molecules at the surface of NPs and cause mistargeting or unintended scavenging by the liver, kidney, or spleen. To overcome this corona issue, we have designed biotin-cysteine conjugated silica NPs (biotin was employed as a targeting molecule and cysteine was used as a zwitterionic ligand) to inhibit corona-induced mistargeting and thus significantly enhance the active targeting capability of NPs in complex biological media. To probe the targeting yield of our engineered NPs, we employed both modified silicon wafer substrates with streptavidin (i.e., biotin receptor) to simulate a target and a cell-based model platform using tumor cell lines that overexpress biotin receptors. In both cases, after incubation with human plasma (thus forming a protein corona), cellular uptake/substrate attachment of the targeted NPs with zwitterionic coatings were significantly higher than the same NPs without zwitterionic coating. Our results demonstrated that NPs with a zwitterionic surface can considerably facilitate targeting yield of NPs and provide a promising new type of nanocarriers in biological applications.

A Cell-targeted Photodynamic Nanomedicine Strategy for Head & Neck Cancers

PubMed Central

Master, Alyssa; Malamas, Anthony; Solanki, Rachna; Clausen, Dana M.; Eiseman, Julie L.; Gupta, Anirban Sen

2013-01-01

Photodynamic Therapy (PDT) holds great promise for the treatment of head and neck (H&N) carcinomas where repeated loco-regional therapy often becomes necessary due to the highly aggressive and recurrent nature of the cancers. While interstitial light delivery technologies are being refined for PDT of H&N and other cancers, a parallel clinically relevant research area is the formulation of photosensitizers in nanovehicles that allow systemic administration yet preferential enhanced uptake in the tumor. This approach can render dual-selectivity of PDT, by harnessing both the drug and the light delivery within the tumor. To this end, we report on a cell-targeted nanomedicine approach for the photosensitizer silicon phthalocyanine-4 (Pc 4), by packaging it within polymeric micelles that are surface-decorated with GE11-peptides to promote enhanced cell-selective binding and receptor-mediated internalization in EGFR-overexpressing H&N cancer cells. Using fluorescence spectroscopy and confocal microscopy, we demonstrate in vitro that the EGFR-targeted Pc 4-nanoformulation undergoes faster and higher uptake in EGFR-overexpressing H&N SCC-15 cells. We further demonstrate that this enhanced Pc 4 uptake results in significant cell-killing and drastically reduced post-PDT clonogenicity. Building on this in vitro data, we demonstrate that the EGFR-targeted Pc 4-nanoformulation results in significant intra-tumoral drug uptake and subsequent enhanced PDT response, in vivo, in SCC-15 xenografts in mice. Altogether our results show significant promise towards a cell-targeted photodynamic nanomedicine for effective treatment of H&N carcinomas. PMID:23531079

Costimulation dependent expression of miR-214 increases the ability of T cells to proliferate by targeting Pten

PubMed Central

Jindra, Peter T.; Bagley, Jessamyn; Godwin, Jonathan G.; Iacomini, John

2010-01-01

T cell activation requires signaling through the T cell receptor (TCR) and costimulatory molecules such as CD28. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression post transcriptionally and are also known to be involved in lymphocyte development and function. Here we set out to examine potential roles of miRNAs in T cell activation by using genome-wide expression profiling to identify miRNAs differentially regulated following T cell activation. One of the miRNAs up-regulated after T cell activation, miR-214, was predicted to be capable of targeting Pten based on bioinformatics and reports suggesting that it targets Pten in ovarian tumor cells. Up-regulation of miR-214 in T cells inversely correlated with PTEN levels. In vivo, transcripts containing the 3' untranslated region (3' UTR) of Pten including the miR-214 target sequence were negatively regulated after T cell activation, and forced expression of miR-214 in T cells led to increased proliferation after stimulation. Blocking CD28 signaling in vivo prevented miR-214 up-regulation in alloreactive T cells. Stimulation of T cells through the TCR alone was not sufficient to result in upregulation of miR-214. Thus, costimulation dependent up-regulation of miR-214 promotes T cell activation by targeting the negative regulator Pten. Thus, the requirement for T cell costimulation is in part related to its ability to regulate expression of miRNAs that control T cell activation. PMID:20548023

Innovative T Cell-Targeted Therapy for Ovarian Cancer

DTIC Science & Technology

2012-10-01

from co-culture with EL4 -ROR1neg and EL4 -ROR1+ tumor targets. Ovarian cancer cell lines (A2780, EFO21, EFO27, IGROV1, OC314, and UPN251) were...profiled for ROR1 expression in normoxia (20% O2) and hypoxia (1% O2). Four-hour CRA was used to evaluate cytotoxicity against the OvCa and EL4 tumor...loaded aAPC for negative controls. EL4 is a murine T cell lymphoma cell line used to test specificity of CAR+ T cells with limited allo-reactivity

Antigen sensitivity of CD22-specific chimeric T cell receptors is modulated by target epitope distance from the cell membrane

PubMed Central

James, Scott E.; Greenberg, Philip D.; Jensen, Michael C.; Lin, Yukang; Wang, Jinjuan; Till, Brian G.; Raubitschek, Andrew A.; Forman, Stephen J.; Press, Oliver W.

2008-01-01

We have targeted CD22 as a novel tumor-associated antigen for recognition by human CTL genetically modified to express chimeric T cell receptors (cTCR) recognizing this surface molecule. CD22-specifc cTCR targeting different epitopes of the CD22 molecule promoted efficient lysis of target cells expressing high levels of CD22 with a maximum lytic potential that appeared to decrease as the distance of the target epitope from the target cell membrane increased. Targeting membrane-distal CD22 epitopes with cTCR+ CTL revealed defects in both degranulation and lytic granule targeting. CD22-specific cTCR+ CTL exhibited lower levels of maximum lysis and lower antigen sensitivity than CTL targeting CD20, which has a shorter extracellular domain than CD22. This diminished sensitivity was not a result of reduced avidity of antigen engagement, but instead reflected weaker signaling per triggered cTCR molecule when targeting membrane-distal epitopes of CD22. Both of these parameters were restored by targeting a ligand expressing the same epitope but constructed as a truncated CD22 molecule to approximate the length of a TCR:pMHC complex. The reduced sensitivity of CD22-specific cTCR+ CTL for antigen-induced triggering of effector functions has potential therapeutic applications, as such cells selectively lysed B cell lymphoma lines expressing high levels of CD22 but demonstrated minimal activity against autologous normal B cells, which express lower levels of CD22. Thus, our results demonstrate that cTCR signal strength – and consequently antigen sensitivity – can be modulated by differential choice of target epitopes with respect to distance from the cell membrane, allowing discrimination between targets with disparate antigen density. PMID:18453625

Antibody-drug conjugate targeting CD46 eliminates multiple myeloma cells.

PubMed

Sherbenou, Daniel W; Aftab, Blake T; Su, Yang; Behrens, Christopher R; Wiita, Arun; Logan, Aaron C; Acosta-Alvear, Diego; Hann, Byron C; Walter, Peter; Shuman, Marc A; Wu, Xiaobo; Atkinson, John P; Wolf, Jeffrey L; Martin, Thomas G; Liu, Bin

2016-12-01

Multiple myeloma is incurable by standard approaches because of inevitable relapse and development of treatment resistance in all patients. In our prior work, we identified a panel of macropinocytosing human monoclonal antibodies against CD46, a negative regulator of the innate immune system, and constructed antibody-drug conjugates (ADCs). In this report, we show that an anti-CD46 ADC (CD46-ADC) potently inhibited proliferation in myeloma cell lines with little effect on normal cells. CD46-ADC also potently eliminated myeloma growth in orthometastatic xenograft models. In primary myeloma cells derived from bone marrow aspirates, CD46-ADC induced apoptosis and cell death, but did not affect the viability of nontumor mononuclear cells. It is of clinical interest that the CD46 gene resides on chromosome 1q, which undergoes genomic amplification in the majority of relapsed myeloma patients. We found that the cell surface expression level of CD46 was markedly higher in patient myeloma cells with 1q gain than in those with normal 1q copy number. Thus, genomic amplification of CD46 may serve as a surrogate for target amplification that could allow patient stratification for tailored CD46-targeted therapy. Overall, these findings indicate that CD46 is a promising target for antibody-based treatment of multiple myeloma, especially in patients with gain of chromosome 1q.

Cell Connections by Tunneling Nanotubes: Effects of Mitochondrial Trafficking on Target Cell Metabolism, Homeostasis, and Response to Therapy

PubMed Central

2017-01-01

Intercellular communications play a major role in tissue homeostasis and responses to external cues. Novel structures for this communication have recently been described. These tunneling nanotubes (TNTs) consist of thin-extended membrane protrusions that connect cells together. TNTs allow the cell-to-cell transfer of various cellular components, including proteins, RNAs, viruses, and organelles, such as mitochondria. Mesenchymal stem cells (MSCs) are both naturally present and recruited to many different tissues where their interaction with resident cells via secreted factors has been largely documented. Their immunosuppressive and repairing capacities constitute the basis for many current clinical trials. MSCs recruited to the tumor microenvironment also play an important role in tumor progression and resistance to therapy. MSCs are now the focus of intense scrutiny due to their capacity to form TNTs and transfer mitochondria to target cells, either in normal physiological or in pathological conditions, leading to changes in cell energy metabolism and functions, as described in this review. PMID:28659978

STAT3 as a potential therapeutic target in ALDH+ and CD44+/CD24+ stem cell-like pancreatic cancer cells.

PubMed

Lin, Li; Jou, David; Wang, Yina; Ma, Haiyan; Liu, Tianshu; Fuchs, James; Li, Pui-Kai; Lü, Jiagao; Li, Chenglong; Lin, Jiayuh

2016-12-01

Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer including pancreatic cancer. Whether STAT3 is activated in stem cell-like pancreatic cancer cells and the effect of STAT3 inhibition, is still unknown. Flow cytometry was used to isolate pancreatic cancer stem-like cells which are identified by both aldehyde dehydrogenase (ALDH)-positive (ALDH+) as well as cluster of differentiation (CD) 44-positive/CD24-positive subpopulations (CD44+/CD24+). STAT3 activation and the effects of STAT3 inhibition by STAT3 inhibitors, LLL12, FLLL32, and Stattic in ALDH+ and CD44+/CD24+ cells were examined. Our results showed that ALDH+ and CD44+/CD24+ pancreatic cancer stem-like cells expressed higher levels of phosphorylated STAT3, an active form of STAT3, compared to ALDH-negative (ALDH-) and CD44-negative/CD24-negative (CD44-/CD24-) pancreatic cancer cells, suggesting that STAT3 is activated in pancreatic cancer stem-like cells. Small molecular STAT3 inhibitors inhibited STAT3 phosphorylation, STAT3 downstream target gene expression, cell viability, and tumorsphere formation in ALDH+ and CD44+/CD24+ cells. Our results indicate that STAT3 is a novel therapeutic target in pancreatic cancer stem-like cells and inhibition of activated STAT3 in these cells by STAT3 inhibitors may offer an effective treatment for pancreatic cancer.

CD22 antigen is broadly expressed on lung cancer cells and is a target for antibody-based therapy.

PubMed

Tuscano, Joseph M; Kato, Jason; Pearson, David; Xiong, Chengyi; Newell, Laura; Ma, Yunpeng; Gandara, David R; O'Donnell, Robert T

2012-11-01

Most patients with lung cancer still die from their disease, necessitating additional options to improve treatment. Here, we provide evidence for targeting CD22, a cell adhesion protein known to influence B-cell survival that we found is also widely expressed in lung cancer cells. In characterizing the antitumor activity of an established anti-CD22 monoclonal antibody (mAb), HB22.7, we showed CD22 expression by multiple approaches in various lung cancer subtypes, including 7 of 8 cell lines and a panel of primary patient specimens. HB22.7 displayed in vitro and in vivo cytotoxicity against CD22-positive human lung cancer cells and tumor xenografts. In a model of metastatic lung cancer, HB22.7 inhibited the development of pulmonary metastasis and extended overall survival. The finding that CD22 is expressed on lung cancer cells is significant in revealing a heretofore unknown mechanism of tumorigenesis and metastasis. Our work suggests that anti-CD22 mAbs may be useful for targeted therapy of lung cancer, a malignancy that has few tumor-specific targets. ©2012 AACR.

Targeting B cells in immune-mediated inflammatory disease: a comprehensive review of mechanisms of action and identification of biomarkers.

PubMed

Dörner, Thomas; Kinnman, Nils; Tak, Paul P

2010-03-01

B cell-depletion therapy, particularly using anti-CD20 treatment, has provided proof of concept that targeting B cells and the humoral response may result in clinical improvements in immune-mediated inflammatory disease. In this review, the mechanisms of action of B cell-targeting drugs are investigated, and potential biomarkers associated with response to treatment in patients with autoimmune diseases are identified. Most available data relate to B cell depletion using anti-CD20 therapy (rituximab) in patients with rheumatoid arthritis (RA). Treatment leads to significant clinical benefit, but apparently fails to deplete long-lived plasma cells, and discontinuation is associated with relapse. Biomarkers commonly used in studies of B cell-targeted therapies include rheumatoid factor, anti-citrullinated peptide antibodies, and immunoglobulin (Ig) levels. More recently, there has been interest in markers such as B cell phenotype analysis, and B lymphocyte stimulator (BLyS)/a proliferation-inducing ligand (APRIL), the latter particularly in studies of the IgG Fc-transmembrane activator and CAML interactor (TACI) fusion protein (atacicept) and anti-BLyS therapy (belimumab). Data from clinical trials of B cell-depleting agents in RA suggest that specific autoantibodies, BLyS, APRIL, and circulating and synovial B lineage cell levels may have potential as biomarkers predictive of response to treatment. Further trials validating these markers against clinical outcomes in RA are required. In patients with systemic lupus erythematosus, Fc receptors and levels of circulating immune cells (including B cells and natural killer cells) may be relevant markers. 2010 Elsevier Inc. All rights reserved.

The Host Range of Gammaretroviruses and Gammaretroviral Vectors Includes Post-Mitotic Neural Cells

PubMed Central

Liu, Xiu-Huai; Xu, Wenqin; Russ, Jill; Eiden, Lee E.; Eiden, Maribeth V.

2011-01-01

Background Gammaretroviruses and gammaretroviral vectors, in contrast to lentiviruses and lentiviral vectors, are reported to be restricted in their ability to infect growth-arrested cells. The block to this restriction has never been clearly defined. The original assessment of the inability of gammaretroviruses and gammaretroviral vectors to infect growth-arrested cells was carried out using established cell lines that had been growth-arrested by chemical means, and has been generalized to neurons, which are post-mitotic. We re-examined the capability of gammaretroviruses and their derived vectors to efficiently infect terminally differentiated neuroendocrine cells and primary cortical neurons, a target of both experimental and therapeutic interest. Methodology/Principal Findings Using GFP expression as a marker for infection, we determined that both growth-arrested (NGF-differentiated) rat pheochromocytoma cells (PC12 cells) and primary rat cortical neurons could be efficiently transduced, and maintained long-term protein expression, after exposure to murine leukemia virus (MLV) and MLV-based retroviral vectors. Terminally differentiated PC12 cells transduced with a gammaretroviral vector encoding the anti-apoptotic protein Bcl-xL were protected from cell death induced by withdrawal of nerve growth factor (NGF), demonstrating gammaretroviral vector-mediated delivery and expression of genes at levels sufficient for therapeutic effect in non-dividing cells. Post-mitotic rat cortical neurons were also shown to be susceptible to transduction by murine replication-competent gammaretroviruses and gammaretroviral vectors. Conclusions/Significance These findings suggest that the host range of gammaretroviruses includes post-mitotic and other growth-arrested cells in mammals, and have implications for re-direction of gammaretroviral gene therapy to neurological disease. PMID:21464894

Di-Ethylhexylphthalate (DEHP) Modulates Cell Invasion, Migration and Anchorage Independent Growth through Targeting S100P in LN-229 Glioblastoma Cells

PubMed Central

Sims, Jennifer Nicole; Graham, Barbara; Pacurari, Maricica; Leggett, Sophia S.; Tchounwou, Paul B.; Ndebele, Kenneth

2014-01-01

Glioblastoma multiforme (GBM) is the most aggressive brain cancer with a median survival of 1–2 years. The treatment of GBM includes surgical resection, radiation and chemotherapy, which minimally extends survival. This poor prognosis necessitates the identification of novel molecular targets associated with glioblastoma. S100P is associated with drug resistance, metastasis, and poor clinical outcomes in many malignancies. The functional role of S100P in glioblastoma has not been fully investigated. In this study, we examined the role of S100P mediating the effects of the environmental contaminant, DEHP, in glioblastoma cells (LN-229) by assessing cell proliferation, apoptosis, anchorage independent growth, cell migration and invasion following DEHP exposure. Silencing S100P and DEHP treatment inhibited LN-229 glioblastoma cell proliferation and induced apoptosis. Anchorage independent growth study revealed significantly decreased colony formation in shS100P cells. We also observed reduced cell migration in cells treated with DEHP following S100P knockdown. Similar results were observed in spheroid formation and expansion. This study is the first to demonstrate the effects of DEHP on glioblastoma cells, and implicates S100P as a potential therapeutic target that may be useful as a drug response biomarker. PMID:24821384

Therapeutic targeting of the p53 pathway in cancer stem cells

PubMed Central

Prabhu, Varun V.; Allen, Joshua E.; Hong, Bo; Zhang, Shengliang; Cheng, Hairong; El-Deiry, Wafik S.

2013-01-01

Introduction Cancer stem cells are a high profile drug target for cancer therapeutics due to their indispensable role in cancer progression, maintenance, and therapeutic resistance. Restoring wild-type p53 function is an attractive new therapeutic approach for the treatment of cancer due to the well-described powerful tumor suppressor function of p53. As emerging evidence intimately links p53 and stem cell biology, this approach also provides an opportunity to target cancer stem cells. Areas covered Therapeutic approaches to restore the function of wild-type p53, cancer and normal stem cell biology in relation to p53, and the downstream effects of p53 on cancer stem cells. Expert opinion The restoration of wild-type p53 function by targeting p53 directly, its interacting proteins, or its family members holds promise as a new class of cancer therapies. This review examines the impact that such therapies may have on normal and cancer stem cells based on the current evidence linking p53 signaling with these populations. PMID:22998602

Eliminating Cancer Stem Cells by Targeting Embryonic Signaling Pathways.

PubMed

Oren, Ohad; Smith, B Douglas

2017-02-01

Dramatic advances have been made in the understanding of cancer over the past decade. Prime among those are better appreciation of the biology of cancer and the development of targeted therapies. Despite these improvements, however, most tumors remain refractory to anti-cancer medications and frequently recur. Cancer Stem Cells (CSCs), which in some cases express markers of pluripotency (e.g., Oct-4), share many of the molecular features of normal stem cells. These cells have been hypothesised to play a role in tumor resistance and relapse. They exhibit dependence on many primitive regulatory pathways and may be best viewed in the context of embryonic signaling pathways. In this article, we review important embryonic signaling cascades and their differential expression in CSCs. We also discuss these pathways as actionable targets for novel therapies in hopes that eliminating cancer stem cells will lead to an improvement in overall survival for patients.

Homoharringtonine targets Smad3 and TGF-β pathway to inhibit the proliferation of acute myeloid leukemia cells.

PubMed

Chen, Jian; Mu, Qitian; Li, Xia; Yin, Xiufeng; Yu, Mengxia; Jin, Jing; Li, Chenying; Zhou, Yile; Zhou, Jiani; Suo, Shanshan; Lu, Demin; Jin, Jie

2017-06-20

Homoharringtonine (HHT) has long and widely been used in China for the treatment of acute myeloid leukemia (AML), the clinical therapeutic effect is significant but the working mechanism is poorly understood. The purpose of this study is to screen the possible target for HHT with virtual screening and verify the findings by cell experiments. Software including Autodock, Python, and MGL tools were used, with HHT being the ligand and proteins from PI3K-Akt pathway, Jak-stat pathway, TGF-β pathway and NK-κB pathway as the receptors. Human AML cell lines including U937, KG-1, THP-1 were cultured and used as the experiment cell lines. MTT assay was used for proliferation detection, flowcytometry was used to detect apoptosis and cell cycle arrest upon HHT functioning, western blotting was used to detect the protein level changes, viral shRNA transfection was used to suppress the expression level of the target protein candidate, and viral mRNA transfection was used for over-expression. Virtual screening revealed that smad3 from TGF-β pathway might be the candidate for HHT binding. In AML cell line U937 and KG-1, HHT can induce the Ser423/425 phosphorylation of smad3, and this phosphorylation can subsequently activate the TGF-β pathway, causing cell cycle arrest at G1 phase in U937 cells and apoptosis in KG-1 cells, knockdown of smad3 can impair the sensitivity of U937 cell to HHT, and over-expression of smad3 can re-establish the sensitivity in both cell lines. We conclude that smad3 is the probable target protein of HHT and plays an important role in the functioning mechanism of HHT.

Homoharringtonine targets Smad3 and TGF-β pathway to inhibit the proliferation of acute myeloid leukemia cells

PubMed Central

Yin, Xiufeng; Yu, Mengxia; Jin, Jing; Li, Chenying; Zhou, Yile; Zhou, Jiani; Suo, Shanshan; Lu, Demin; Jin, Jie

2017-01-01

Homoharringtonine (HHT) has long and widely been used in China for the treatment of acute myeloid leukemia (AML), the clinical therapeutic effect is significant but the working mechanism is poorly understood. The purpose of this study is to screen the possible target for HHT with virtual screening and verify the findings by cell experiments. Software including Autodock, Python, and MGL tools were used, with HHT being the ligand and proteins from PI3K-Akt pathway, Jak-stat pathway, TGF-β pathway and NK-κB pathway as the receptors. Human AML cell lines including U937, KG-1, THP-1 were cultured and used as the experiment cell lines. MTT assay was used for proliferation detection, flowcytometry was used to detect apoptosis and cell cycle arrest upon HHT functioning, western blotting was used to detect the protein level changes, viral shRNA transfection was used to suppress the expression level of the target protein candidate, and viral mRNA transfection was used for over-expression. Virtual screening revealed that smad3 from TGF-β pathway might be the candidate for HHT binding. In AML cell line U937 and KG-1, HHT can induce the Ser423/425 phosphorylation of smad3, and this phosphorylation can subsequently activate the TGF-β pathway, causing cell cycle arrest at G1 phase in U937 cells and apoptosis in KG-1 cells, knockdown of smad3 can impair the sensitivity of U937 cell to HHT, and over-expression of smad3 can re-establish the sensitivity in both cell lines. We conclude that smad3 is the probable target protein of HHT and plays an important role in the functioning mechanism of HHT. PMID:28454099

Cell-permeable, mitochondrial-targeted, peptide antioxidants.

PubMed

Szeto, Hazel H

2006-04-21

Cellular oxidative injury has been implicated in aging and a wide array of clinical disorders including ischemia-reperfusion injury; neurodegenerative diseases; diabetes; inflammatory diseases such as atherosclerosis, arthritis, and hepatitis; and drug-induced toxicity. However, available antioxidants have not proven to be particularly effective against many of these disorders. A possibility is that some of the antioxidants do not reach the relevant sites of free radical generation, especially if mitochondria are the primary source of reactive oxygen species (ROS). The SS (Szeto-Schiller) peptide antioxidants represent a novel approach with targeted delivery of antioxidants to the inner mitochondrial membrane. The structural motif of these SS peptides centers on alternating aromatic residues and basic amino acids (aromatic-cationic peptides). These SS peptides can scavenge hydrogen peroxide and peroxynitrite and inhibit lipid peroxidation. Their antioxidant action can be attributed to the tyrosine or dimethyltyrosine residue. By reducing mitochondrial ROS, these peptides inhibit mitochondrial permeability transition and cytochrome c release, thus preventing oxidant-induced cell death. Because these peptides concentrate >1000-fold in the inner mitochondrial membrane, they prevent oxidative cell death with EC50 in the nM range. Preclinical studies support their potential use for ischemia-reperfusion injury and neurodegenerative disorders. Although peptides have often been considered to be poor drug candidates, these small peptides have excellent "druggable" properties, making them promising agents for many diseases with unmet needs.

PEGylated anticancer-carbon nanotubes complex targeting mitochondria of lung cancer cells

NASA Astrophysics Data System (ADS)

Kim, Sang-Woo; Lee, Yeon Kyung; Lee, Jong Yeon; Hong, Jeong Hee; Khang, Dongwoo

2017-11-01

Although activating apoptosis in cancer cells by targeting the mitochondria is an effective strategy for cancer therapy, insufficient targeting of the mitochondria in cancer cells restricts the availability in clinical treatment. Here, we report on a polyethylene glycol-coated carbon nanotube (CNT)-ABT737 nanodrug that improves the mitochondrial targeting of lung cancer cells. The polyethylene glycol-coated CNT-ABT737 nanodrug internalized into the early endosomes via macropinocytosis and clathrin-mediated endocytosis in advance of early endosomal escape and delivered into the mitochondria. Cytosol release of the nanodrug led to apoptosis of lung cancer cells by abruption of the mitochondrial membrane potential, inducing Bcl-2-mediated apoptosis and generating intracellular reactive oxygen species. As such, this study provides an effective strategy for increasing the anti-lung cancer efficacy by increasing mitochondria accumulation rate of cytosol released anticancer nanodrugs.

Application of molecular targeted therapies in the treatment of head and neck squamous cell carcinoma.

PubMed

Kozakiewicz, Paulina; Grzybowska-Szatkowska, Ludmiła

2018-05-01

Despite the development of standard therapies, including surgery, radiotherapy and chemotherapy, survival rates for head and neck squamous cell carcinoma (HNSCC) have not changed significantly over the past three decades. Complete recovery is achieved in <50% of patients. The treatment of advanced HNSCC frequently requires multimodality therapy and involves significant toxicity. The promising, novel treatment option for patients with HNSCC is molecular-targeted therapies. The best known targeted therapies include: Epidermal growth factor receptor (EGFR) monoclonal antibodies (cetuximab, panitumumab, zalutumumab and nimotuzumab), EGFR tyrosine kinase inhibitors (gefitinib, erlotinib, lapatinib, afatinib and dacomitinib), vascular endothelial growth factor (VEGF) inhibitor (bevacizumab) or vascular endothelial growth factor receptor (VEGFR) inhibitors (sorafenib, sunitinib and vandetanib) and inhibitors of phosphatidylinositol 3-kinase/serine/threonine-specific protein kinase/mammalian target of rapamycin. There are also various inhibitors of other pathways and targets, which are promising and require evaluation in further studies.

Targeted Genome Editing Using DNA-Free RNA-Guided Cas9 Ribonucleoprotein for CHO Cell Engineering.

PubMed

Shin, Jongoh; Lee, Namil; Cho, Suhyung; Cho, Byung-Kwan

2018-01-01

Recent advances in the CRISPR/Cas9 system have dramatically facilitated genome engineering in various cell systems. Among the protocols, the direct delivery of the Cas9-sgRNA ribonucleoprotein (RNP) complex into cells is an efficient approach to increase genome editing efficiency. This method uses purified Cas9 protein and in vitro transcribed sgRNA to edit the target gene without vector DNA. We have applied the RNP complex to CHO cell engineering to obtain desirable phenotypes and to reduce unintended insertional mutagenesis and off-target effects. Here, we describe our routine methods for RNP complex-mediated gene deletion including the protocols to prepare the purified Cas9 protein and the in vitro transcribed sgRNA. Subsequently, we also describe a protocol to confirm the edited genomic positions using the T7E1 enzymatic assay and next-generation sequencing.

Update on B-cell targeted therapies for systemic lupus erythematosus.

PubMed

Mok, Chi Chiu

2014-06-01

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by flares and remission, leading to accrual of organ damage over time as a result of persistent tissue inflammation and treatment-related complications. Novel therapies aiming at better treatment response and fewer adverse effects are being tested in the pipeline. This review summarizes the B-cell abnormalities observed in patients with SLE, and updates recent data on the efficacy and safety of B-cell targeted therapies in the treatment of SLE. The pitfalls of clinical trial design and future directions of the development of SLE therapeutics are discussed. The variability of clinical response to treatment in SLE reflects the clinical and immunological heterogeneity of the disease. The treatment plan for patients with SLE should be individualized with the aim of eradicating disease activity, preventing flares and minimizing treatment-related complications. Despite the disappointment of recent clinical trials, B-cell remains the promising target of future SLE therapies. Results from ongoing clinical trials on B-cell targeted biological agents are eagerly awaited.

Delineating CD4 dependency of HIV-1: Adaptation to infect low level CD4 expressing target cells widens cellular tropism but severely impacts on envelope functionality

PubMed Central

Beauparlant, David; Rusert, Peter; Magnus, Carsten; Weber, Jacqueline; Uhr, Therese; Clapham, Paul R.; Metzner, Karin J.

2017-01-01

A hallmark of HIV-1 infection is the continuously declining number of the virus’ predominant target cells, activated CD4+ T cells. With diminishing CD4+ T cell levels, the capacity to utilize alternate cell types and receptors, including cells that express low CD4 receptor levels such as macrophages, thus becomes crucial. To explore evolutionary paths that allow HIV-1 to acquire a wider host cell range by infecting cells with lower CD4 levels, we dissected the evolution of the envelope-CD4 interaction under in vitro culture conditions that mimicked the decline of CD4high target cells, using a prototypic subtype B, R5-tropic strain. Adaptation to CD4low targets proved to severely alter envelope functions including trimer opening as indicated by a higher affinity to CD4 and loss in shielding against neutralizing antibodies. We observed a strikingly decreased infectivity on CD4high target cells, but sustained infectivity on CD4low targets, including macrophages. Intriguingly, the adaptation to CD4low targets altered the kinetic of the entry process, leading to rapid CD4 engagement and an extended transition time between CD4 and CCR5 binding during entry. This phenotype was also observed for certain central nervous system (CNS) derived macrophage-tropic viruses, highlighting that the functional perturbation we defined upon in vitro adaptation to CD4low targets occurs in vivo. Collectively, our findings suggest that CD4low adapted envelopes may exhibit severe deficiencies in entry fitness and shielding early in their evolution. Considering this, adaptation to CD4low targets may preferentially occur in a sheltered and immune-privileged environment such as the CNS to allow fitness restoring compensatory mutations to occur. PMID:28264054

Phosphotyrosine profiling identifies ephrin receptor A2 as a potential therapeutic target in esophageal squamous‐cell carcinoma

PubMed Central

Syed, Nazia; Barbhuiya, Mustafa A.; Pinto, Sneha M.; Nirujogi, Raja Sekhar; Renuse, Santosh; Datta, Keshava K.; Khan, Aafaque Ahmad; Srikumar, Kotteazeth; Prasad, T. S. Keshava; Kumar, M. Vijaya; Kumar, Rekha Vijay; Chatterjee, Aditi; Pandey, Akhilesh

2015-01-01

Esophageal squamous‐cell carcinoma (ESCC) is one of the most common malignancies in Asia. Currently, surgical resection of early‐stage tumor is the best available treatment. However, most patients present late when surgery is not an option. Data suggest that chemotherapy regimens are inadequate for clinical management of advanced cancer. Targeted therapy has emerged as one of the most promising approaches to treat several malignancies. A prerequisite for developing targeted therapy is prior knowledge of proteins and pathways that drive proliferation in malignancies. We carried out phosphotyrosine profiling across four different ESCC cell lines and compared it to non‐neoplastic Het‐1A cell line to identify activated tyrosine kinase signaling pathways in ESCC. A total of 278 unique phosphopeptides were identified across these cell lines. This included several tyrosine kinases and their substrates that were hyperphosphorylated in ESCC. Ephrin receptor A2 (EPHA2), a receptor tyrosine kinase, was hyperphosphorylated in all the ESCC cell lines used in the study. EPHA2 is reported to be oncogenic in several cancers and is also known to promote metastasis. Immunohistochemistry‐based studies have revealed EPHA2 is overexpressed in nearly 50% of ESCC. We demonstrated EPHA2 as a potential therapeutic target in ESCC by carrying out siRNA‐based knockdown studies. Knockdown of EPHA2 in ESCC cell line TE8 resulted in significant decrease in cell proliferation and invasion, suggesting it is a promising therapeutic target in ESCC that warrants further evaluation. PMID:25366905

Targeting PYK2 mediates microenvironment-specific cell death in multiple myeloma

PubMed Central

Meads, MB; Fang, B; Mathews, L; Gemmer, J; Nong, L; Rosado-Lopez, I; Nguyen, T; Ring, JE; Matsui, W; MacLeod, AR; Pachter, JA; Hazlehurst, LA; Koomen, JM; Shain, KH

2015-01-01

Multiple myeloma (MM) remains an incurable malignancy due, in part, to the influence of the bone marrow microenvironment on survival and drug response. Identification of microenvironment-specific survival signaling determinants is critical for the rational design of therapy and elimination of MM. Previously, we have shown that collaborative signaling between β1 integrin-mediated adhesion to fibronectin and interleukin-6 confers a more malignant phenotype via amplification of signal transducer and activator of transcription 3 (STAT3) activation. Further characterization of the events modulated under these conditions with quantitative phosphotyrosine profiling identified 193 differentially phosphorylated peptides. Seventy-seven phosphorylations were upregulated upon adhesion, including PYK2/FAK2, Paxillin, CASL and p130CAS consistent with focal adhesion (FA) formation. We hypothesized that the collaborative signaling between β1 integrin and gp130 (IL-6 beta receptor, IL-6 signal transducer) was mediated by FA formation and proline-rich tyrosine kinase 2 (PYK2) activity. Both pharmacological and molecular targeting of PYK2 attenuated the amplification of STAT3 phosphorylation under co-stimulatory conditions. Co-culture of MM cells with patient bone marrow stromal cells (BMSC) showed similar β1 integrin-specific enhancement of PYK2 and STAT3 signaling. Molecular and pharmacological targeting of PYK2 specifically induced cell death and reduced clonogenic growth in BMSC-adherent myeloma cell lines, aldehyde dehydrogenase-positive MM cancer stem cells and patient specimens. Finally, PYK2 inhibition similarly attenuated MM progression in vivo. These data identify a novel PYK2-mediated survival pathway in MM cells and MM cancer stem cells within the context of microenvironmental cues, providing preclinical support for the use of the clinical stage FAK/PYK2 inhibitors for treatment of MM, especially in a minimal residual disease setting. PMID:26387544

Therapeutic targeting of sunitinib-induced AR phosphorylation in renal cell carcinoma.

PubMed

Adelaiye-Ogala, Remi; Damayanti, Nur P; Orillion, Ashley R; Arisa, Sreevani; Chintala, Sreenivasulu; Titus, Mark A; Kao, Chinghai; Pili, Roberto

2018-03-23

Androgen receptor (AR) plays a crucial role in the development and progression of prostate cancer. AR expression has also been reported in other solid tumors, including renal cell carcinoma (RCC), but its biological role here remains unclear. Through integrative analysis of a reverse phase protein array (RPPA), we discovered increased expression of AR in an RCC patient-derived xenograft model of acquired resistance to the receptor tyrosine kinase inhibitor (RTKi) sunitinib. AR expression was increased in RCC cell lines with either acquired or intrinsic sunitinib resistance in vitro. An AR signaling gene array profiler indicated elevated levels of AR target genes in sunitinib-resistant cells. Sunitinib-induced AR transcriptional activity was associated with increased phosphorylation of serine 81 (pS81) on AR. Additionally, AR overexpression resulted in acquired sunitinib resistance, and the AR antagonist enzalutamide-induced AR degradation and attenuated AR downstream activity in sunitinib-resistant cells, also indicated by decreased secretion of human kallikrein 2 (KLK2). Enzalutamide-induced AR degradation was rescued by either proteasome inhibition or by knockdown of the AR ubiquitin ligase speckle-type POZ protein (SPOP). In vivo treatment with enzalutamide and sunitinib demonstrated that this combination efficiently induced tumor regression in an RCC model following acquired sunitinib resistance. Overall, our results suggest the potential role of AR as a target for therapeutic interventions, in combination with RTKi, to overcome drug resistance in RCC. Copyright ©2018, American Association for Cancer Research.

Construction of ultrasonic nanobubbles carrying CAIX polypeptides to target carcinoma cells derived from various organs.

PubMed

Zhu, Lianhua; Guo, Yanli; Wang, Luofu; Fan, Xiaozhou; Xiong, Xingyu; Fang, Kejing; Xu, Dan

2017-09-29

Ultrasound molecular imaging is a novel diagnostic approach for tumors, whose key link is the construction of targeted ultrasound contrast agents. However, available targeted ultrasound contrast agents for molecular imaging of tumors are only achieving imaging in blood pool or one type tumor. No targeted ultrasound contrast agents have realized targeted ultrasound molecular imaging of tumor parenchymal cells in a variety of solid tumors so far. Carbonic anhydrase IX (CAIX) is highly expressed on cell membranes of various malignant solid tumors, so it's a good target for ultrasound molecular imaging. Here, targeted nanobubbles carrying CAIX polypeptides for targeted binding to a variety of malignant tumors were constructed, and targeted binding ability and ultrasound imaging effect in different types of tumors were evaluated. The mean diameter of lipid targeted nanobubbles was (503.7 ± 78.47) nm, and the polypeptides evenly distributed on the surfaces of targeted nanobubbles, which possessed the advantages of homogenous particle size, high stability, and good safety. Targeted nanobubbles could gather around CAIX-positive cells (786-O and Hela cells), while they cannot gather around CAIX-negative cells (BxPC-3 cells) in vitro, and the affinity of targeted nanobubbles to CAIX-positive cells were significantly higher than that to CAIX-negative cells (P < 0.05). Peak intensity and duration time of targeted nanobubbles and blank nanobubbles were different in CAIX-positive transplanted tumor tissues in vivo (P < 0.05). Moreover, targeted nanobubbles in CAIX-positive transplanted tumor tissues produced higher peak intensity and longer duration time than those in CAIX-negative transplanted tumor tissues (P < 0.05). Finally, immunofluorescence not only confirmed targeted nanobubbles could pass through blood vessels to enter in tumor tissue spaces, but also clarified imaging differences of targeted nanobubbles in different types of transplanted tumor tissues

Off-target effects of sulforaphane include the derepression of long terminal repeats through histone acetylation events.

PubMed

Baier, Scott R; Zbasnik, Richard; Schlegel, Vicki; Zempleni, Janos

2014-06-01

Sulforaphane is a naturally occurring isothiocyanate in cruciferous vegetables. Sulforaphane inhibits histone deacetylases, leading to the transcriptional activation of genes including tumor suppressor genes. The compound has attracted considerable attention in the chemoprevention of prostate cancer. Here we tested the hypothesis that sulforaphane is not specific for tumor suppressor genes but also activates loci such as long terminal repeats (LTRs), which might impair genome stability. Studies were conducted using chemically pure sulforaphane in primary human IMR-90 fibroblasts and in broccoli sprout feeding studies in healthy adults. Sulforaphane (2.0 μM) caused an increase in LTR transcriptional activity in cultured cells. Consumption of broccoli sprouts (34, 68 or 102 g) by human volunteers caused a dose dependent elevation in LTR mRNA in circulating leukocytes, peaking at more than a 10-fold increase. This increase in transcript levels was associated with an increase in histone H3 K9 acetylation marks in LTR 15 in peripheral blood mononuclear cells from subjects consuming sprouts. Collectively, this study suggests that sulforaphane has off-target effects that warrant further investigation when recommending high levels of sulforaphane intake, despite its promising activities in chemoprevention. Copyright © 2014 Elsevier Inc. All rights reserved.

Preclinical Assessment of CAR T-Cell Therapy Targeting the Tumor Antigen 5T4 in Ovarian Cancer

PubMed Central

Owens, Gemma L.; Sheard, Victoria E.; Kalaitsidou, Milena; Blount, Daniel; Lad, Yatish; Cheadle, Eleanor J.; Edmondson, Richard J.; Kooner, Gurdeep; Gilham, David E.

2018-01-01

Chimeric antigen receptor (CAR) T cells represent a novel targeted approach to overcome both quantitative and qualitative shortfalls of the host immune system relating to the detection and subsequent destruction of tumors. The identification of antigens expressed specifically on the surface of tumor cells is a critical first step in the ability to utilize CAR T cells for the treatment of cancer. The 5T4 is a tumor-associated antigen which is expressed on the cell surface of most solid tumors including ovarian cancer. Matched blood and tumor samples were collected from 12 patients with ovarian cancer; all tumors were positive for 5T4 expression by immunohistochemistry. Patient T cells were effectively transduced with 2 different anti-5T4 CAR constructs which differed in their affinity for the target antigen. Co-culture of CAR T cells with matched autologous tumor disaggregates resulted in antigen-specific secretion of IFN-gamma. Furthermore, assessment of the efficacy of anti-5T4 CAR T cells in a mouse model resulted in therapeutic benefit against established ovarian tumors. These results demonstrate proof of principle that 5T4 is an attractive target for immune intervention in ovarian cancer and that patient T cells engineered to express a 5T4-specific CAR can recognize and respond physiologically to autologous tumor cells. PMID:29239915

Interactome Analysis of Microtubule-targeting Agents Reveals Cytotoxicity Bases in Normal Cells.

PubMed

Gutiérrez-Escobar, Andrés Julián; Méndez-Callejas, Gina

2017-12-01

Cancer causes millions of deaths annually and microtubule-targeting agents (MTAs) are the most commonly-used anti-cancer drugs. However, the high toxicity of MTAs on normal cells raises great concern. Due to the non-selectivity of MTA targets, we analyzed the interaction network in a non-cancerous human cell. Subnetworks of fourteen MTAs were reconstructed and the merged network was compared against a randomized network to evaluate the functional richness. We found that 71.4% of the MTA interactome nodes are shared, which affects cellular processes such as apoptosis, cell differentiation, cell cycle control, stress response, and regulation of energy metabolism. Additionally, possible secondary targets were identified as client proteins of interphase microtubules. MTAs affect apoptosis signaling pathways by interacting with client proteins of interphase microtubules, suggesting that their primary targets are non-tumor cells. The paclitaxel and doxorubicin networks share essential topological axes, suggesting synergistic effects. This may explain the exacerbated toxicity observed when paclitaxel and doxorubicin are used in combination for cancer treatment. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

New Wnt/β-catenin target genes promote experimental metastasis and migration of colorectal cancer cells through different signals.

PubMed

Qi, Jingjing; Yu, Yong; Akilli Öztürk, Özlem; Holland, Jane D; Besser, Daniel; Fritzmann, Johannes; Wulf-Goldenberg, Annika; Eckert, Klaus; Fichtner, Iduna; Birchmeier, Walter

2016-10-01

We have previously identified a 115-gene signature that characterises the metastatic potential of human primary colon cancers. The signature included the canonical Wnt target gene BAMBI, which promoted experimental metastasis in mice. Here, we identified three new direct Wnt target genes from the signature, and studied their functions in epithelial-mesenchymal transition (EMT), cell migration and experimental metastasis. We examined experimental liver metastases following injection of selected tumour cells into spleens of NOD/SCID mice. Molecular and cellular techniques were used to identify direct transcription target genes of Wnt/β-catenin signals. Microarray analyses and experiments that interfered with cell migration through inhibitors were performed to characterise downstream signalling systems. Three new genes from the colorectal cancer (CRC) metastasis signature, BOP1, CKS2 and NFIL3, were identified as direct transcription targets of β-catenin/TCF4. Overexpression and knocking down of these genes in CRC cells promoted and inhibited, respectively, experimental metastasis in mice, EMT and cell motility in culture. Cell migration was repressed by interfering with distinct signalling systems through inhibitors of PI3K, JNK, p38 mitogen-activated protein kinase and/or mTOR. Gene expression profiling identified a series of migration-promoting genes, which were induced by BOP1, CKS2 and NFIL3, and could be repressed by inhibitors that are specific to these pathways. We identified new direct Wnt/β-catenin target genes, BOP1, CKS2 and NFIL3, which induced EMT, cell migration and experimental metastasis of CRC cells. These genes crosstalk with different downstream signalling systems, and activate migration-promoting genes. These pathways and downstream genes may serve as therapeutic targets in the treatment of CRC metastasis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Glioblastoma-targeted CD4+ CAR T cells mediate superior antitumor activity.

PubMed

Wang, Dongrui; Aguilar, Brenda; Starr, Renate; Alizadeh, Darya; Brito, Alfonso; Sarkissian, Aniee; Ostberg, Julie R; Forman, Stephen J; Brown, Christine E

2018-05-17

Chimeric antigen receptor-modified (CAR-modified) T cells have shown promising therapeutic effects for hematological malignancies, yet limited and inconsistent efficacy against solid tumors. The refinement of CAR therapy requires an understanding of the optimal characteristics of the cellular products, including the appropriate composition of CD4+ and CD8+ subsets. Here, we investigated the differential antitumor effect of CD4+ and CD8+ CAR T cells targeting glioblastoma-associated (GBM-associated) antigen IL-13 receptor α2 (IL13Rα2). Upon stimulation with IL13Rα2+ GBM cells, the CD8+ CAR T cells exhibited robust short-term effector function but became rapidly exhausted. By comparison, the CD4+ CAR T cells persisted after tumor challenge and sustained their effector potency. Mixing with CD4+ CAR T cells failed to ameliorate the effector dysfunction of CD8+ CAR T cells, while surprisingly, CD4+ CAR T cell effector potency was impaired when coapplied with CD8+ T cells. In orthotopic GBM models, CD4+ outperformed CD8+ CAR T cells, especially for long-term antitumor response. Further, maintenance of the CD4+ subset was positively correlated with the recursive killing ability of CAR T cell products derived from GBM patients. These findings identify CD4+ CAR T cells as a highly potent and clinically important T cell subset for effective CAR therapy.

Glioblastoma-targeted CD4+ CAR T cells mediate superior antitumor activity

PubMed Central

Wang, Dongrui; Starr, Renate; Alizadeh, Darya; Brito, Alfonso; Sarkissian, Aniee; Ostberg, Julie R.; Forman, Stephen J.; Brown, Christine E.

2018-01-01

Chimeric antigen receptor–modified (CAR-modified) T cells have shown promising therapeutic effects for hematological malignancies, yet limited and inconsistent efficacy against solid tumors. The refinement of CAR therapy requires an understanding of the optimal characteristics of the cellular products, including the appropriate composition of CD4+ and CD8+ subsets. Here, we investigated the differential antitumor effect of CD4+ and CD8+ CAR T cells targeting glioblastoma-associated (GBM-associated) antigen IL-13 receptor α2 (IL13Rα2). Upon stimulation with IL13Rα2+ GBM cells, the CD8+ CAR T cells exhibited robust short-term effector function but became rapidly exhausted. By comparison, the CD4+ CAR T cells persisted after tumor challenge and sustained their effector potency. Mixing with CD4+ CAR T cells failed to ameliorate the effector dysfunction of CD8+ CAR T cells, while surprisingly, CD4+ CAR T cell effector potency was impaired when coapplied with CD8+ T cells. In orthotopic GBM models, CD4+ outperformed CD8+ CAR T cells, especially for long-term antitumor response. Further, maintenance of the CD4+ subset was positively correlated with the recursive killing ability of CAR T cell products derived from GBM patients. These findings identify CD4+ CAR T cells as a highly potent and clinically important T cell subset for effective CAR therapy. PMID:29769444

A systems biology approach identified different regulatory networks targeted by KSHV miR-K12-11 in B cells and endothelial cells.

PubMed

Yang, Yajie; Boss, Isaac W; McIntyre, Lauren M; Renne, Rolf

2014-08-08

Kaposi's sarcoma associated herpes virus (KSHV) is associated with tumors of endothelial and lymphoid origin. During latent infection, KSHV expresses miR-K12-11, an ortholog of the human tumor gene hsa-miR-155. Both gene products are microRNAs (miRNAs), which are important post-transcriptional regulators that contribute to tissue specific gene expression. Advances in target identification technologies and molecular interaction databases have allowed a systems biology approach to unravel the gene regulatory networks (GRNs) triggered by miR-K12-11 in endothelial and lymphoid cells. Understanding the tissue specific function of miR-K12-11 will help to elucidate underlying mechanisms of KSHV pathogenesis. Ectopic expression of miR-K12-11 differentially affected gene expression in BJAB cells of lymphoid origin and TIVE cells of endothelial origin. Direct miRNA targeting accounted for a small fraction of the observed transcriptome changes: only 29 genes were identified as putative direct targets of miR-K12-11 in both cell types. However, a number of commonly affected biological pathways, such as carbohydrate metabolism and interferon response related signaling, were revealed by gene ontology analysis. Integration of transcriptome profiling, bioinformatic algorithms, and databases of protein-protein interactome from the ENCODE project identified different nodes of GRNs utilized by miR-K12-11 in a tissue-specific fashion. These effector genes, including cancer associated transcription factors and signaling proteins, amplified the regulatory potential of a single miRNA, from a small set of putative direct targets to a larger set of genes. This is the first comparative analysis of miRNA-K12-11's effects in endothelial and B cells, from tissues infected with KSHV in vivo. MiR-K12-11 was able to broadly modulate gene expression in both cell types. Using a systems biology approach, we inferred that miR-K12-11 establishes its GRN by both repressing master TFs and influencing

Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined Malaria Proteins

DTIC Science & Technology

2015-11-01

AWARD NUMBER: W81XWH-13-1-0139 TITLE: Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined...DATES COVERED 15Aug2013 - 14Aug2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-13-1-0139 Targeting Common but Complex Proteoglycans on...outbreaks in epidemic regions of the world. Prior to this application we discovered that human breast cancer cells express this same carbohydrate

Design of ligand-targeted nanoparticles for enhanced cancer targeting

NASA Astrophysics Data System (ADS)

Stefanick, Jared F.

Ligand-targeted nanoparticles are increasingly used as drug delivery vehicles for cancer therapy, yet have not consistently produced successful clinical outcomes. Although these inconsistencies may arise from differences in disease models and target receptors, nanoparticle design parameters can significantly influence therapeutic efficacy. By employing a multifaceted synthetic strategy to prepare peptide-targeted nanoparticles with high purity, reproducibility, and precisely controlled stoichiometry of functionalities, this work evaluates the roles of polyethylene glycol (PEG) coating, ethylene glycol (EG) peptide-linker length, peptide hydrophilicity, peptide density, and nanoparticle size on tumor targeting in a systematic manner. These parameters were analyzed in multiple disease models by targeting human epidermal growth factor receptor 2 (HER2) in breast cancer and very late antigen-4 (VLA-4) in multiple myeloma to demonstrate the widespread applicability of this approach. By increasing the hydrophilicity of the targeting peptide sequence and simultaneously optimizing the EG peptide-linker length, the in vitro cellular uptake of targeted liposomes was significantly enhanced. Specifically, including a short oligolysine chain adjacent to the targeting peptide sequence effectively increased cellular uptake ~80-fold using an EG6 peptide-linker compared to ~10-fold using an EG45 linker. In vivo, targeted liposomes prepared in a traditional manner lacking the oligolysine chain demonstrated similar biodistribution and tumor uptake to non-targeted liposomes. However, by including the oligolysine chain, targeted liposomes using an EG45 linker significantly improved tumor uptake ~8-fold over non-targeted liposomes, while the use of an EG6 linker decreased tumor accumulation and uptake, owing to differences in cellular uptake kinetics, clearance mechanisms, and binding site barrier effects. To further improve tumor targeting and enhance the selectivity of targeted

Dual peptide-mediated targeted delivery of bioactive siRNAs to oral cancer cells in vivo.

PubMed

Alexander-Bryant, Angela A; Zhang, Haiwen; Attaway, Christopher C; Pugh, William; Eggart, Laurence; Sansevere, Robert M; Andino, Lourdes M; Dinh, Lu; Cantini, Liliana P; Jakymiw, Andrew

2017-09-01

Despite significant advances in cancer treatment, the prognosis for oral cancer remains poor in comparison to other cancer types, including breast, skin, and prostate. As a result, more effective therapeutic modalities are needed for the treatment of oral cancer. Consequently, in the present study, we examined the feasibility of using a dual peptide carrier approach, combining an epidermal growth factor receptor (EGFR)-targeting peptide with an endosome-disruptive peptide, to mediate targeted delivery of small interfering RNAs (siRNAs) into EGFR-overexpressing oral cancer cells and induce silencing of the targeted oncogene, cancerous inhibitor of protein phosphatase 2A (CIP2A). Fluorescence microscopy, real-time PCR, Western blot analysis, and in vivo bioimaging of mice containing orthotopic xenograft tumors were used to examine the ability of the dual peptide carrier to mediate specific delivery of bioactive siRNAs into EGFR-overexpressing oral cancer cells/tissues. Co-complexation of the EGFR-targeting peptide, GE11R9, with the endosome-disruptive 599 peptide facilitated the specific uptake of siRNAs into oral cancer cells overexpressing EGFR in vitro with optimal gene silencing observed at a 60:30:1 (GE11R9:599:siRNA) molar ratio. Furthermore, when administered systemically to mice bearing xenograft oral tumors, this dual peptide complex mediated increased targeted delivery of siRNAs into tumor tissues in comparison to the 599 peptide alone and significantly enhanced CIP2A silencing. Herein we provide the first report demonstrating the clinical potential of a dual peptide strategy for siRNA-based therapeutics by synergistically mediating the effective targeting and delivery of bioactive siRNAs into EGFR-overexpressing oral cancer cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

Immunotherapy targeting HER2 with genetically modified T cells eliminates tumor-initiating cells in osteosarcoma.

PubMed

Rainusso, N; Brawley, V S; Ghazi, A; Hicks, M J; Gottschalk, S; Rosen, J M; Ahmed, N

2012-03-01

Despite radical surgery and multi-agent chemotherapy, less than one third of patients with recurrent or metastatic osteosarcoma (OS) survive. The limited efficacy of current therapeutic approaches to target tumor-initiating cells (TICs) may explain this dismal outcome. The purpose of this study was to assess the impact of modified T cells expressing a human epidermal growth factor receptor (HER2)-specific chimeric antigen receptor in the OS TIC compartment of human established cell lines. Using the sarcosphere formation assay, we found that OS TICs were resistant to increasing methotrexate concentrations. In contrast, HER2-specific T cells decreased markedly sarcosphere formation capacity and the ability to generate bone tumors in immunodeficient mice after orthotopic transplantation. In vivo, administration of HER2-specific T cells significantly reduced TICs in bulky tumors as judged by decreased sarcosphere forming efficiency in OS cells isolated from explanted tumors. We demonstrate that HER2-specific T cells target drug resistant TICs in established OS cell lines, suggesting that incorporating immunotherapy into current treatment strategies for OS has the potential to improve outcomes.

A targeted mutational landscape of angioimmunoblastic T-cell lymphoma

PubMed Central

Odejide, Oreofe; Weigert, Oliver; Lane, Andrew A.; Toscano, Dan; Lunning, Matthew A.; Kopp, Nadja; Kim, Sunhee; van Bodegom, Diederik; Bolla, Sudha; Schatz, Jonathan H.; Teruya-Feldstein, Julie; Hochberg, Ephraim; Louissaint, Abner; Dorfman, David; Stevenson, Kristen; Rodig, Scott J.; Piccaluga, Pier Paolo; Jacobsen, Eric; Pileri, Stefano A.; Harris, Nancy L.; Ferrero, Simone; Inghirami, Giorgio; Horwitz, Steven M.

2014-01-01

The genetics of angioimmunoblastic T-cell lymphoma (AITL) are very poorly understood. We defined the mutational landscape of AITL across 219 genes in 85 cases from the United States and Europe. We identified ≥2 mutations in 34 genes, nearly all of which were not previously implicated in AITL. These included loss-of-function mutations in TP53 (n = 4), ETV6 (n = 3), CCND3 (n = 2), and EP300 (n = 5), as well as gain-of-function mutations in JAK2 (n = 2) and STAT3 (n = 4). TET2 was mutated in 65 (76%) AITLs, including 43 that harbored 2 or 3 TET2 mutations. DNMT3A mutations occurred in 28 (33%) AITLs; 100% of these also harbored TET2 mutations (P < .0001). Seventeen AITLs harbored IDH2 R172 substitutions, including 15 with TET2 mutations. In summary, AITL is characterized by high frequencies of overlapping mutations in epigenetic modifiers and targetable mutations in a subset of cases. PMID:24345752