RESUMEN
Since the 1980s there has been a drive toward personalized targeted therapy for cancer. "Targeted cancer therapy" originally focused on inhibiting essential tumor survival factors, primarily protein tyrosine kinases. The complexity and rapid mutability of tumors, however, enable them to develop resistance to tyrosine kinase inhibitors (TKIs), even when these are multitargeted or applied in combination. This has led to the development of targeted cancer immunotherapy, to enhance immune surveillance against the tumor. In this paper, we provide a personal view of the development of targeted therapy, from TKIs to targeted immunotherapy.
Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Humanos , Inmunoterapia/métodos , Terapia Molecular Dirigida/métodos , Neoplasias/metabolismoRESUMEN
The small-molecule drug NT157 has demonstrated promising efficacy in preclinical models of a number of different cancer types, reflecting activity against both cancer cells and the tumor microenvironment. Two known mechanisms of action are degradation of insulin receptor substrates (IRS)-1/2 and reduced Stat3 activation, although it is possible that others exist. To interrogate the effects of this drug on cell signaling pathways in an unbiased manner, we have undertaken mass spectrometry-based global tyrosine phosphorylation profiling of NT157-treated A375 melanoma cells. Bioinformatic analysis of the resulting dataset resolved 5 different clusters of tyrosine-phosphorylated peptides that differed in the directionality and timing of response to drug treatment over time. The receptor tyrosine kinase AXL exhibited a rapid decrease in phosphorylation in response to drug treatment, followed by proteasome-dependent degradation, identifying an additional potential target for NT157 action. However, NT157 treatment also resulted in increased activation of p38 MAPK α and γ, as well as the JNKs and specific Src family kinases. Importantly, cotreatment with the p38 MAPK inhibitor SB203580 attenuated the antiproliferative effect of NT157, while synergistic inhibition of cell proliferation was observed when NT157 was combined with a Src inhibitor. These findings provide novel insights into NT157 action on cancer cells and highlight how globally profiling the impact of a specific drug on cellular signaling networks can identify effective combination treatments. Mol Cancer Ther; 17(5); 931-42. ©2018 AACR.
Asunto(s)
Proteínas Tirosina Quinasas/metabolismo , Proteómica/métodos , Pirogalol/análogos & derivados , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Fosfoproteínas/metabolismo , Fosforilación/efectos de los fármacos , Mapas de Interacción de Proteínas/efectos de los fármacos , Proteínas Tirosina Quinasas/clasificación , Proteínas Proto-Oncogénicas c-yes/genética , Proteínas Proto-Oncogénicas c-yes/metabolismo , Pirogalol/farmacología , Interferencia de ARNRESUMEN
Superantigens (SAgs) are extremely potent bacterial toxins, which evoke a virulent immune response, inducing nonspecific T-cell proliferation, rapid cytokine release, and lethal toxic shock, for which there is no effective treatment. We previously developed a small molecule, S101, which potently inhibits proliferating T cells. In a severe mouse model of toxic shock, a single injection of S101 given together with superantigen challenge rescued 100% of the mice. Even when given 2 hours after challenge, S101 rescued 40% of the mice. S101 targets the T-cell receptor, inflammatory response, and actin cytoskeleton pathways. S101 inhibits the aryl hydrocarbon receptor, a ligand-activated transcription factor that is involved in the differentiation of T-helper cells, especially Th17, and regulatory T cells. Our results provide the rationale for developing S101 to treat superantigen-induced toxic shock and other pathologies characterized by T-cell activation and proliferation.
Asunto(s)
Factores Inmunológicos/administración & dosificación , Choque Séptico/prevención & control , Choque Séptico/terapia , Superantígenos/toxicidad , Linfocitos T/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Femenino , Inyecciones Intravenosas , Ratones , Ratones Endogámicos BALB C , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
There is an urgent need for an effective treatment for metastatic prostate cancer (PC). Prostate tumors invariably overexpress prostate surface membrane antigen (PSMA). We designed a nonviral vector, PEI-PEG-DUPA (PPD), comprising polyethylenimine-polyethyleneglycol (PEI-PEG) tethered to the PSMA ligand, 2-[3-(1, 3-dicarboxy propyl)ureido] pentanedioic acid (DUPA), to treat PC. The purpose of PEI is to bind polyinosinic/polycytosinic acid (polyIC) and allow endosomal release, while DUPA targets PC cells. PolyIC activates multiple pathways that lead to tumor cell death and to the activation of bystander effects that harness the immune system against the tumor, attacking nontargeted neighboring tumor cells and reducing the probability of acquired resistance and disease recurrence. Targeting polyIC directly to tumor cells avoids the toxicity associated with systemic delivery. PPD selectively delivered polyIC into PSMA-overexpressing PC cells, inducing apoptosis, cytokine secretion, and the recruitment of human peripheral blood mononuclear cells (PBMCs). PSMA-overexpressing tumors in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with partially reconstituted immune systems were significantly shrunken following PPD/polyIC treatment, in all cases. Half of the tumors showed complete regression. PPD/polyIC invokes antitumor immunity, but unlike many immunotherapies does not need to be personalized for each patient. The potent antitumor effects of PPD/polyIC should spur its development for clinical use.
Asunto(s)
Glutamato Carboxipeptidasa II/antagonistas & inhibidores , Poli I-C/farmacología , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología , Traslado Adoptivo , Animales , Antígenos de Superficie/genética , Antígenos de Superficie/metabolismo , Efecto Espectador , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Modelos Animales de Enfermedad , Expresión Génica , Glutamato Carboxipeptidasa II/genética , Glutamato Carboxipeptidasa II/metabolismo , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Masculino , Ratones , Poli I-C/química , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Unión Proteica , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The treatment of metastatic androgen-resistant prostate cancer remains a challenge. We describe a protein vector that selectively delivers synthetic dsRNA, polyinosinic/polycytidylic acid (polyIC), to prostate tumors by targeting prostate specific membrane antigen (PSMA), which is overexpressed on the surface of prostate cancer cells.The chimeric protein is built from the double stranded RNA (dsRNA) binding domain of PKR tethered to a single chain anti-PSMA antibody. When complexed with polyIC, the chimera demonstrates selective and efficient killing of prostate cancer cells. The treatment causes the targeted cancer cells to undergo apoptosis and to secrete toxic cytokines. In a "bystander effect", these cytokines kill neighboring cancer cells that do not necessarily overexpress PSMA, and activate immune cells that enhance the killing effect. The strong effects of the targeted polyIC are demonstrated on both 2D cell cultures and 3D tumor spheroids.
Asunto(s)
Antígenos de Superficie/genética , Efecto Espectador/efectos de los fármacos , Efecto Espectador/genética , Vectores Genéticos/genética , Glutamato Carboxipeptidasa II/genética , ARN Bicatenario/genética , Proteínas Recombinantes de Fusión/genética , Animales , Antígenos de Superficie/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Quimiotaxis de Leucocito/efectos de los fármacos , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Expresión Génica , Genes Reporteros , Terapia Genética , Vectores Genéticos/administración & dosificación , Glutamato Carboxipeptidasa II/antagonistas & inhibidores , Glutamato Carboxipeptidasa II/metabolismo , Humanos , Ratones , Neoplasias/genética , Neoplasias/mortalidad , Neoplasias/patología , Neoplasias/terapia , Poli I-C/química , Proteínas Recombinantes de Fusión/metabolismo , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/farmacología , Esferoides Celulares , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Selective delivery of drugs to tumor cells can increase potency and reduce toxicity. In this study, we describe a novel recombinant chimeric protein, dsRBEC, which can bind polyIC and deliver it selectively into EGFR over-expressing tumor cells. dsRBEC, comprises the dsRNA binding domain (dsRBD) of human PKR (hPKR), which serves as the polyIC binding moiety, fused to human EGF (hEGF), the targeting moiety. dsRBEC shows high affinity towards EGFR and triggers ligand-induced endocytosis of the receptor, thus leading to the selective internalization of polyIC into EGFR over-expressing tumor cells. The targeted delivery of polyIC by dsRBEC induced cellular apoptosis and the secretion of IFN-ß and other pro-inflammatory cytokines. dsRBEC-delivered polyIC is much more potent than naked polyIC and is expected to reduce the toxicity caused by systemic delivery of polyIC.
Asunto(s)
Apoptosis/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Receptores ErbB/genética , Inductores de Interferón/farmacología , Poli I-C/farmacología , Proteínas Recombinantes de Fusión/genética , Animales , Línea Celular Tumoral , Quimiocina CCL5/biosíntesis , Quimiocina CCL5/metabolismo , Clonación Molecular , Endocitosis , Factor de Crecimiento Epidérmico/genética , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Humanos , Inductores de Interferón/química , Inductores de Interferón/metabolismo , Interferón beta/biosíntesis , Interferón beta/metabolismo , Células MCF-7 , Poli I-C/química , Poli I-C/metabolismo , Unión Proteica , Dominios Proteicos , Proteínas Recombinantes de Fusión/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/metabolismo , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismoRESUMEN
The development of targeted therapies that affect multiple signaling pathways and stimulate antitumor immunity is greatly needed. About 20% of patients with breast cancer overexpress HER2. Small molecules and antibodies targeting HER2 convey some survival benefits; however, patients with advanced disease succumb to the disease under these treatment regimens, possibly because HER2 is not completely necessary for the survival of the targeted cancer cells. In the present study, we show that a polyinosine/polycytosine (pIC) HER2-homing chemical vector induced the demise of HER2-overexpressing breast cancer cells, including trastuzumab-resistant cells. Targeting pIC to the tumor evoked a number of cell-killing mechanisms, as well as strong bystander effects. These bystander mechanisms included type I IFN induction, immune cell recruitment, and activation. The HER2-targeted pIC strongly inhibited the growth of HER2-overexpressing tumors in immunocompetent mice. The data presented here could open additional avenues in the treatment of HER2-positive breast cancer. Cancer Immunol Res; 4(8); 688-97. ©2016 AACR.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias/inmunología , Neoplasias/patología , Poli I-C/administración & dosificación , Receptor ErbB-2/antagonistas & inhibidores , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Humanos , Mediadores de Inflamación/metabolismo , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Microambiente Tumoral/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Insulin-like growth factor (IGF) signaling is associated with castrate-resistant prostate cancer (CRPC) progression. Insulin receptor substrates 1 and 2 (IRS1/2) mediate mitogenic and antiapoptotic signaling from IGF1 receptor (IGF1R), insulin receptor, and other oncoproteins. This study demonstrates that IRS1/2 expression is increased in prostate cancer, and persists in CRPC. Furthermore, this study assesses the anticancer activity of NT157, a small molecule tyrphostin targeting IRS proteins, using androgen-responsive (LNCaP) and -independent (PC3) prostate cancer cells in vitro and in vivo. NT157 treatment resulted in dose-dependent inhibition of IGF1R activation, suppression of IRS protein expression, inhibition of IGF1-induced AKT activation, but increased ERK activation in NT157-treated cells in vitro. These effects were correlated with decreased proliferation and increasing apoptosis of LNCaP cells and increasing G2-M arrest in PC3 cells. NT157 also suppressed androgen-responsive growth, delayed CRPC progression of LNCaP xenografts, and suppressed PC3 tumor growth alone and in combination with docetaxel. This study reports the first preclinical proof-of-principle data that this novel small molecule tyrosine kinase inhibitor suppresses IRS1/2 expression, delays CRPC progression, and suppresses growth of CRPC tumors in vitro and in vivo. Demonstration that IRS expression can be increased in response to a variety of stressors that may lead to resistance or reduced effect of the therapies indicate that NT157-mediated IRS1/2 downregulation is a novel therapeutic approach for management of advanced prostate cancer.
Asunto(s)
Proteínas Sustrato del Receptor de Insulina/metabolismo , Neoplasias de la Próstata/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Tirfostinos/farmacología , Animales , Antineoplásicos Hormonales/farmacología , Antineoplásicos Hormonales/uso terapéutico , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Docetaxel , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas Sustrato del Receptor de Insulina/genética , Masculino , Ratones , Orquiectomía , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteolisis , Receptor IGF Tipo 1/metabolismo , Transducción de Señal/efectos de los fármacos , Taxoides/farmacología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
In the very first article that appeared in Cellular Signalling, published in its inaugural issue in October 1989, we reviewed signal transduction pathways in Saccharomyces cerevisiae. Although this yeast was already a powerful model organism for the study of cellular processes, it was not yet a valuable instrument for the investigation of signaling cascades. In 1989, therefore, we discussed only two pathways, the Ras/cAMP and the mating (Fus3) signaling cascades. The pivotal findings concerning those pathways undoubtedly contributed to the realization that yeast is a relevant model for understanding signal transduction in higher eukaryotes. Consequently, the last 25 years have witnessed the discovery of many signal transduction pathways in S. cerevisiae, including the high osmotic glycerol (Hog1), Stl2/Mpk1 and Smk1 mitogen-activated protein (MAP) kinase pathways, the TOR, AMPK/Snf1, SPS, PLC1 and Pkr/Gcn2 cascades, and systems that sense and respond to various types of stress. For many cascades, orthologous pathways were identified in mammals following their discovery in yeast. Here we review advances in the understanding of signaling in S. cerevisiae over the last 25 years. When all pathways are analyzed together, some prominent themes emerge. First, wiring of signaling cascades may not be identical in all S. cerevisiae strains, but is probably specific to each genetic background. This situation complicates attempts to decipher and generalize these webs of reactions. Secondly, the Ras/cAMP and the TOR cascades are pivotal pathways that affect all processes of the life of the yeast cell, whereas the yeast MAP kinase pathways are not essential. Yeast cells deficient in all MAP kinases proliferate normally. Another theme is the existence of central molecular hubs, either as single proteins (e.g., Msn2/4, Flo11) or as multisubunit complexes (e.g., TORC1/2), which are controlled by numerous pathways and in turn determine the fate of the cell. It is also apparent that lipid signaling is less developed in yeast than in higher eukaryotes. Finally, feedback regulatory mechanisms seem to be at least as important and powerful as the pathways themselves. In the final chapter of this essay we dare to imagine the essence of our next review on signaling in yeast, to be published on the 50th anniversary of Cellular Signalling in 2039.
Asunto(s)
Membrana Celular/metabolismo , Modelos Biológicos , Saccharomyces cerevisiae/metabolismo , Transducción de Señal , AnimalesRESUMEN
The delivery of nucleic acids into cells is an attractive approach for cancer therapy. Polyethylenimine (PEI) is among the most efficient nonviral carriers. Recent studies have demonstrated that PEI can be conjugated to targeting ligands, such as epidermal growth factor (EGF) and transferrin (Schaffert et al., 2011; Abourbeh et al., 2012; Ogris et al., 1999). Herein we present a simplified protocol for producing homogeneous preparations of PEGylated linear PEI: LPEI-PEG2k. We generated two well-characterized copolymers, with ratios of LPEI to PEG of 1:1 and 1:3. These copolymers were further conjugated through disulfide bonds to a Her-2 targeting moiety, Her-2 affibody. This reaction yielded two triconjugates that target Her-2 overexpressing tumors. Polyplexes were formed by complexing plasmid DNA with the triconjugates. We characterized the biophysical properties of the conjugates, and found that the triconjugate 1:3 polyplex had lower ζ potential, larger particle size, and more heterogeneous shape than the triconjugate 1:1 polyplex. Triconjugate 1:1 and triconjugate 1:3 polyplexes were highly selective toward cells that overexpress Her-2 receptors, but triconjugate 1:1 polyplex was more efficient at gene delivery. Our studies show that the biophysical and biological properties of the conjugates can be profoundly affected by the ratio of LPEI:PEG2k:ligand. The procedure described here can be adapted to generate a variety of triconjugates, simply by changing the targeting moiety.
Asunto(s)
ADN/química , Portadores de Fármacos/química , Polietilenglicoles/química , Polietileneimina/química , Línea Celular Tumoral , ADN/genética , ADN/metabolismo , Desoxirribonucleasas/metabolismo , Humanos , Ligandos , Peso Molecular , Estructura Terciaria de Proteína , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Compuestos de Sulfhidrilo/química , TransfecciónRESUMEN
The epidermal growth factor receptor (EGFR) undergoes a conformational change in response to ligand binding. The ligand-induced changes in cell surface aggregation and mobility have a profound effect on the function of all the family members. Ligand also activates the EGFR intracellular kinase, stimulating proliferation and cell survival. The EGFR family are often activated, overexpressed or mutated in cancer cells and therapeutic drugs (including antibodies) can slow the progress of some cancers. This article provides a brief, annotated summary of the presentations and discussion which occurred at the Epidermal Growth Factor Receptor - Future Directions Conference held in Jerusalem in November 2013.
Asunto(s)
Receptores ErbB/metabolismo , Receptores ErbB/uso terapéutico , Neoplasias/tratamiento farmacológico , Animales , Humanos , Proteínas de la Membrana/metabolismo , Ratones , Unión Proteica , Conformación Proteica , Transporte de Proteínas , Receptor ErbB-2/metabolismo , Transducción de SeñalRESUMEN
A series of degrasyn-like symmetrical compounds have been designed, synthesized, and screened against B cell malignancy (multiple myeloma, mantle cell lymphoma) cell lines. The lead compounds T5165804 and CP2005 showed higher nanomolar potency against these tumor cells in comparison to degrasyn and inhibited Usp9x activity in vitro and in intact cells. These observations suggest that this new class of compounds holds promise as cancer therapeutic agents.
Asunto(s)
Antineoplásicos/química , Nitrilos/química , Piridinas/química , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cianoacrilatos , Dimerización , Humanos , Modelos Moleculares , Mieloma Múltiple/tratamiento farmacológico , Nitrilos/farmacología , Nitrilos/uso terapéutico , Piridinas/farmacología , Piridinas/uso terapéutico , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Ubiquitina Tiolesterasa/metabolismoRESUMEN
The understanding that the immune system plays a dual role in cancer progression has led to the recent development of targeted immunotherapies. These treatments, which aim to harness the immune system against cancer, include monoclonal antibodies, immune adjuvants, cell-based therapy and vaccines. Although numerous immune-targeted treatment modalities have entered the clinic, most have shown limited efficacy. The intrinsic heterogeneity and genomic instability of the tumor, coupled with immune suppression induced by both the tumor and its microenvironment, remain the main obstacles to the success of these therapies. We believe that the primary objective of the new generation of therapies must be to reinstate immune surveillance against primary and metastatic tumor cells, while inhibiting the immune suppressive microenvironment. Most probably this will be achieved by combining several treatment modalities. This paper will briefly review current immunotherapies and their promise, as well as the obstacles associated with them.
Asunto(s)
Inmunoterapia , Neoplasias/terapia , Animales , Anticuerpos/uso terapéutico , Antígenos de Neoplasias/inmunología , Antineoplásicos/uso terapéutico , Vacunas contra el Cáncer , Humanos , Neoplasias/inmunologíaRESUMEN
Insulin receptor substrates 1 and 2 (IRS1/2) mediate mitogenic and antiapoptotic signaling from insulin-like growth factor 1 receptor (IGF-IR), insulin receptor (IR), and other oncoproteins. IRS1 plays a central role in cancer cell proliferation, its expression is increased in many human malignancies, and its upregulation mediates resistance to anticancer drugs. IRS2 is associated with cancer cell motility and metastasis. Currently, there are no anticancer agents that target IRS1/2. We present new IGF-IR/IRS-targeted agents (NT compounds) that promote inhibitory Ser-phosphorylation and degradation of IRS1 and IRS2. Elimination of IRS1/2 results in long-term inhibition of IRS1/2-mediated signaling. The therapeutic significance of this inhibition in cancer cells was shown while unraveling a novel mechanism of resistance to B-RAF(V600E/K) inhibitors. We found that IRS1 is upregulated in PLX4032-resistant melanoma cells and in cell lines derived from patients whose tumors developed PLX4032 resistance. In both settings, NT compounds led to the elimination of IRS proteins and evoked cell death. Treatment with NT compounds in vivo significantly inhibited the growth of PLX4032-resistant tumors and displayed potent antitumor effects in ovarian and prostate cancers. Our findings offer preclinical proof-of-concept for IRS1/2 inhibitors as cancer therapeutics including PLX4032-resistant melanoma. By the elimination of IRS proteins, such agents should prevent acquisition of resistance to mutated-B-RAF inhibitors and possibly restore drug sensitivity in resistant tumors.
Asunto(s)
Antineoplásicos/farmacología , Proteínas Sustrato del Receptor de Insulina/metabolismo , Melanoma/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Animales , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Femenino , Células HCT116 , Células Hep G2 , Humanos , Proteínas Sustrato del Receptor de Insulina/antagonistas & inhibidores , Proteínas Sustrato del Receptor de Insulina/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Melanoma/genética , Melanoma/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Transformation is a complex process, involving many changes in the cell. In this work, we investigated the transcriptional changes that arose during the development of squamous cell carcinoma (SCC) in mice. Using microarray analysis, we looked at gene expression during different stages in cancer progression in 31 mice. By analyzing tumor progression in each mouse separately, we were able to define the global changes that were common to all 31 mice, as well as significant changes that occurred in fewer individuals. We found that different genes can contribute to the tumorigenic process in different mice, and that there are many ways to acquire the malignant properties defined by Hanahan and Weinberg as "hallmarks of cancer". Eventually, however, all these changes lead to a very similar cancerous phenotype. The finding that gene expression is strongly heterogeneous in tumors that were induced by a standardized protocol in closely related mice underscores the need for molecular characterization of human tumors and personalized therapy.
Asunto(s)
Carcinoma de Células Escamosas/genética , Transformación Celular Neoplásica/genética , Neoplasias Cutáneas/genética , Animales , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/patología , Muerte Celular/genética , Progresión de la Enfermedad , Femenino , Expresión Génica , Genes cdc , Humanos , Masculino , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , Papiloma/etiología , Papiloma/genética , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/patologíaRESUMEN
With the manufacture of imatinib, researchers introduced tyrosine kinase inhibitors (TKIs) into the clinical setting in 2000 to treat cancers; approximately fifteen other TKIs soon followed. Imatinib remains the most successful agent, whereas all the others have had modest effects on the cancers that they target. The current challenge is to identify the agents that need to be combined with TKIs to maximize their efficacy. One of the most promising approaches is to combine immune therapy with TKI treatment. In this review, the therapeutic potential of TKIs for treatment is discussed.
Asunto(s)
Benzamidas/farmacología , Benzamidas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Piperazinas/farmacología , Piperazinas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Animales , Humanos , Mesilato de ImatinibRESUMEN
Cancer researchers have been looking for ways to harness the immune system and to reinstate immune surveillance, to kill cancer cells without collateral damage. Here we scan current approaches to targeting the immune system against cancer, and emphasize our own approach. We are using chemical vectors attached to a specific ligand, to introduce synthetic dsRNA, polyinosine/cytosine (polyIC), into tumors. The ligand binds to a receptor protein that is overexpressed on the surface of the tumor cells. Upon ligand binding, the receptor complex is internalized, introducing the polyIC into the cell. In this fashion a large amount of synthetic dsRNA can be internalized, leading to the activation of dsRNA-binding proteins, such as dsRNA dependent protein kinase (PKR), Toll-like receptor 3 (TLR3), retinoic acid-inducible gene I (RIG-1), and melanoma differentiation-associated gene 5 (MDA5). The simultaneous activation of these signaling proteins leads to the rapid demise of the targeted cell and to cytokine secretion. The cytokines lead to a strong bystander effect and to the recruitment of immune cells that converge upon the targeted cells. The bystander effects lead to the destruction of neighboring tumor cells not targeted themselves by the vector. Normal cells, being more robust than tumor cells, survive. This strategy has several advantages: (1) recruitment of the immune system is localized to the tumor. (2) The response is rapid, leading to fast tumor eradication. (3) The bystander effects lead to the eradication of tumor cells not harboring the target. (4) The multiplicity of pro-death signaling pathways elicited by PolyIC minimizes the likelihood of the emergence of resistance. In this chapter we focus on EGFR as the targeted receptor, which is overexpressed in many tumors. In principle, the strategy can be extended to other tumors that overexpress a protein that can be internalized by a ligand, which can be a small molecule, a single chain antibody, or an affibody.
RESUMEN
Computers are organized into hardware and software. Using a theoretical approach to identify patterns in gene expression in a variety of species, organs, and cell types, we found that biological systems similarly are comprised of a relatively unchanging hardware-like gene pattern. Orthogonal patterns of software-like transcripts vary greatly, even among tumors of the same type from different individuals. Two distinguishable classes could be identified within the hardware-like component: those transcripts that are highly expressed and stable and an adaptable subset with lower expression that respond to external stimuli. Importantly, we demonstrate that this structure is conserved across organisms. Deletions of transcripts from the highly stable core are predicted to result in cell mortality. The approach provides a conceptual thermodynamic-like framework for the analysis of gene-expression levels and networks and their variations in diseased cells.
Asunto(s)
Redes Reguladoras de Genes , Modelos Genéticos , Animales , Línea Celular Tumoral , Computadores , Perfilación de la Expresión Génica , Humanos , Ratones , Modelos Biológicos , Modelos Estadísticos , Programas Informáticos , Biología de Sistemas , Termodinámica , Transcripción GenéticaRESUMEN
Phage display has identified the dodecapeptide YHWYGYTPQNVI (GE11) as a ligand that binds to the epidermal growth factor receptor (EGFR) but does not activate the receptor. Here, we compare the EGFR binding affinities of GE11, EGF, and their polyethyleneimine-polyethyleneglycol (PEI-PEG) conjugates. We found that although GE11 by itself does not exhibit measurable affinity to the EGFR, tethering it to PEI-PEG increases its affinity markedly, and complex formation with polyinosine/cytosine (polyIC) further enhances the affinity to the submicromolar range. PolyIC/PPGE11 has a similar strong antitumor effect against EGFR overexpressing tumors in vitro and in vivo, as polyIC/polyethyleneimine-polyetheleneglycol-EGF (polyIC/PP-EGF). Absence of EGFR activation, as previously shown by us and easier production of GE11 and GE11 conjugates, confer polyIC/PPGE11 a significant advantage over similar EGF-based polyplexes as a potential therapy of EGFR overexpressing tumors.
Asunto(s)
Receptores ErbB/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Péptidos/administración & dosificación , Poli I-C/administración & dosificación , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Humanos , Ligandos , Ratones , Ratones Desnudos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Polietilenglicoles/administración & dosificación , Polietileneimina/administración & dosificación , Polietileneimina/análogos & derivados , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Protein-protein interactions (PPIs) govern nearly all processes in living cells. Peptides play an important role in studying PPIs. Peptides carrying photoaffinity labels that covalently bind the interacting protein can be used to obtain more accurate information regarding PPIs. Benzophenone (BP) is a useful photoaffinity label that is widely used to study PPIs. We developed a one-pot two-step synthesis for the preparation of novel BP units. To map the binding site more thoroughly, linkers of various lengths were attached to the BP moiety. These units can be incorporated into peptide sequences using well-established solid phase peptide synthesis (SPPS) protocols. As a proof of concept, we studied the interaction between protein kinase B (PKB/Akt) and its synthetic peptide inhibitor, PTR6154. The methodology is general and can be implemented to study PPIs in a variety of biological systems.