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1.
J Zool (1987) ; 299(2): 106-115, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27453637

RESUMO

Social monogamy is a mating strategy rarely employed by mammalian species. Laboratory studies in socially monogamous prairie voles (Microtus ochrogaster) demonstrate that oxytocin and vasopressin act within the mesolimbic dopamine pathway to facilitate pair-bond formation. Species differences in oxytocin receptor (OTR) and vasopressin 1a receptor (V1aR) distribution in this pathway are associated with species differences in mating strategy. Here we characterize the neuroanatomical distribution of OTR and V1aR binding sites in naturally occurring populations of Taiwan voles (M. kikuchii), which purportedly display social monogamy. Live trapping was conducted at two sites in 2009-2010 and receptor autoradiography for OTR and V1aR was performed on brains from 24 animals. OTR binding in two brain regions where OTR signaling regulates pair-bonding were directly compared with that of prairie voles. Our results show that like prairie voles, Taiwan voles exhibit OTR in the prefrontal cortex, insular cortex, claustrum, nucleus accumbens, caudate-putamen, dorsal lateral septal nucleus, central amygdala, and ventromedial hypothalamus. Unlike prairie voles, Taiwan voles exhibit OTR binding in the CA3 pathway of the hippocampus, as well as the indusium griseum, which has only previously been documented in tuco-tucos (Ctenomys haigi, C. sociabilis), Syrian hamsters (Mesocricetus auratus) and naked mole-rats (Heterocephalus glaber). V1aR binding was present in the ventral pallidum, lateral septum, nucleus basalis, bed nucleus of the stria terminalis, hippocampus, medial amygdala, and anterior, ventromedial and dorsomedial hypothalamus. Marked individual differences in V1aR binding were noted in the cingulate cortex and several thalamic nuclei, remarkably similar to prairie voles. While pharmacological studies are needed to determine whether oxytocin and vasopressin are involved in pair-bond formation in this species, our results lay a foundation for future investigations into the role of these neuropeptides in Taiwan vole social behavior.

2.
Mol Psychiatry ; 18(3): 308-19, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22290119

RESUMO

The lateral division of the bed nucleus of the stria terminalis (BNST), which forms part of the circuitry regulating fear and anxiety, contains a large number of neurons expressing corticotropin releasing factor (CRF), a neuropeptide that has a prominent role in the etiology of fear- and anxiety-related psychopathologies. Stress increases CRF expression within BNST neurons, implicating these cells in stress- and anxiety-related behaviors. These experiments examined the effect of chronically enhanced CRF expression within BNST neurons on conditioned and unconditioned anxiety-related behavior by using a lentiviral vector containing a promoter that targets CRF gene overexpression (OE) to CRFergic cells. We found that BNST CRF-OE did not affect unconditioned anxiety-like responses in the elevated plus maze or basal acoustic startle amplitude. CRF-OE induced before training weakened sustained fear (conditioned anxiety); when induced after conditioning, CRF-OE increased expression of the conditioned emotional memory. Increased BNST CRF expression did not affect plasma corticosterone concentration but did decrease CRFR1 receptor density within the BNST and CRFR2 receptor density within the dorsal portion of the caudal dorsal raphe nucleus. These data raise the possibility that the observed behavioral effects may be mediated by enhanced CRF receptor signaling or compensatory changes in CRF receptor density within these structures. Together, these studies demonstrate that CRF neurons within the lateral BNST modulate conditioned anxiety-like behaviors and also suggest that enhanced CRF expression within these neurons may contribute to inappropriate regulation of emotional memories.


Assuntos
Ansiedade/fisiopatologia , Condicionamento Psicológico/fisiologia , Hormônio Liberador da Corticotropina/fisiologia , Núcleos Septais/fisiologia , Animais , Ansiedade/sangue , Ansiedade/metabolismo , Corticosterona/sangue , Hormônio Liberador da Corticotropina/biossíntese , Masculino , Neurônios/metabolismo , Neurônios/fisiologia , Núcleos da Rafe/metabolismo , Ratos , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Núcleos Septais/metabolismo
3.
Sci Rep ; 10(1): 17301, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057124

RESUMO

Social cognition is facilitated by oxytocin receptors (OXTR) in the hippocampus, a brain region that changes dynamically with pregnancy, parturition, and parenting experience. We investigated the impact of parenthood on hippocampal OXTR in male and female titi monkeys, a pair-bonding primate species that exhibits biparental care of offspring. We hypothesized that in postmortem brain tissue, OXTR binding in the hippocampal formation would differ between parents and non-parents, and that OXTR density would correlate with frequencies of observed parenting and affiliative behaviors between partners. Subjects were 10 adult titi monkeys. OXTR binding in the hippocampus (CA1, CA2/3, CA4, dentate gyrus, subiculum) and presubiculum layers (PSB1, PSB3) was determined using receptor autoradiography. The average frequency of partner affiliation (Proximity, Contact, and Tail Twining) and infant carrying were determined from longitudinal observations (5-6 per day). Analyses showed that parents exhibited higher OXTR binding than non-parents in PSB1 (t(8) = - 2.33, p = 0.048), and that OXTR binding in the total presubiculm correlated negatively with Proximity (r = - 0.88) and Contact (r = - 0.91), but not Tail Twining or infant carrying. These results suggest that OXTR binding in the presubiculum supports pair bonding and parenting behavior, potentially by mediating changes in hippocampal plasticity.


Assuntos
Comportamento Animal/fisiologia , Hipocampo/metabolismo , Hipocampo/fisiologia , Plasticidade Neuronal/fisiologia , Ligação do Par , Poder Familiar/psicologia , Receptores de Ocitocina/metabolismo , Cognição Social , Animais , Callicebus , Feminino , Masculino , Giro Para-Hipocampal/metabolismo , Giro Para-Hipocampal/fisiologia
4.
Science ; 243(4888): 220-2, 1989 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-2911735

RESUMO

By virtue of its immediate contact with the circulating blood, the endothelium provides an attractive target for retroviral vector transduction for the purpose of gene therapy. To see whether efficient gene transfer and expression was feasible, rabbit aortic endothelial cells were infected with three Moloney murine leukemia virus-derived retroviral vectors. Two of these vectors carry genes encoding products that are not secreted: N2, containing only the selectable marker gene neoR, and SAX, containing both neoR gene and an SV40-promoted adenosine deaminase (ADA) gene. The third vector, G2N, contains a secretory rat growth hormone (rGH) gene and an SV40-promoted neoR gene. Infection with all three vectors resulted in expression of the respective genes. A high level of human ADA expression was observed in infected endothelial cell populations both before and after selection in G418. G2N-infected rabbit aortic endothelial cells that were grown on a synthetic vascular graft continued to secrete rGH into the culture medium. These studies suggest that endothelial cells may serve as vehicles for the introduction in vivo of functioning recombinant genes.


Assuntos
Endotélio Vascular/metabolismo , Genes Virais , Genes , Vetores Genéticos , Vírus da Leucemia Murina de Moloney/genética , Transdução Genética , Transfecção , Adenosina Desaminase/análise , Adenosina Desaminase/genética , Animais , Aorta , DNA Recombinante/metabolismo , Marcadores Genéticos/análise , Hormônio do Crescimento/análise , Hormônio do Crescimento/genética , Regiões Promotoras Genéticas , Coelhos , Ratos , Proteínas Recombinantes/análise
5.
Cancer Res ; 53(21): 5274-83, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8221662

RESUMO

Tumor cells expressing the herpes simplex virus thymidine kinase (HSV-TK) gene are sensitive to the drug ganciclovir (GCV). We demonstrate here that HSV-TK-positive cells exposed to GCV were lethal to HSV-TK-negative cells as a result of a "bystander effect." HSV-TK-negative cells were killed in vitro when the population of cultured cells contained only 10% HSV-TK-positive cells. The mechanism of this "bystander effect" on HSV-TK-negative cells appeared to be related to the process of apoptotic cell death when HSV-TK-positive cells were exposed to GCV. Flow cytometric and electron microscopic analyses suggested that apoptotic vesicles generated from the dying gene-modified cells were phagocytized by nearby, unmodified tumor cells. Prevention of apoptotic vesicle transfer prevented the bystander effect. The toxic effect of HSV-TK-positive cells on HSV-TK-negative cells was reproduced in an in vivo model. A mixed population of tumor cells consisting of HSV-TK-positive and HSV-TK-negative cells was inoculated s.c. into mice. Regression of the tumor mass occurred when the inoculum consisted of as few as 10% HSV-TK-expressing tumor cells. The bystander effect was also demonstrated in i.p. tumor studies. Initial experiments demonstrated that prolonged survival (> 70 days) occurred when a mixture containing 50% HSV-TK-positive and 50% HSV-TK-negative cells was injected i.p. followed by GCV treatment. Further, survival was prolonged for mice with a preexisting HSV-TK-negative i.p. tumor burden by injecting HSV-TK-positive cells and GCV. These results suggest that genetic modification of tumor cells may be useful for developing cancer therapies.


Assuntos
Apoptose , Ganciclovir/toxicidade , Vírus do Sarcoma Murino de Kirsten , Infecções por Retroviridae/patologia , Sarcoma Experimental/patologia , Timidina Quinase/genética , Infecções Tumorais por Vírus/patologia , Animais , Linhagem Celular Transformada , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Infecções por Retroviridae/genética , Sarcoma Experimental/genética , Sarcoma Experimental/ultraestrutura , Simplexvirus/enzimologia , Simplexvirus/genética , Infecções Tumorais por Vírus/genética
6.
Pharmacol Ther ; 66(1): 175-90, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7630929

RESUMO

Gene therapy involves the insertion of a gene into an organism to treat a disease. Since its early development in the 1970s, gene therapy has expanded rapidly both in terms of the methods available and the number of candidate diseases for treatment. This report reviews gene therapy for cancer, including methodology, pre-clinical studies and experimental clinical trials.


Assuntos
Terapia Genética/tendências , Neoplasias/terapia , Oligonucleotídeos Antissenso/uso terapêutico , Ensaios Clínicos como Assunto , Citocinas/administração & dosagem , Citocinas/uso terapêutico , Sistemas de Liberação de Medicamentos , Vetores Genéticos , Células Germinativas/patologia , Humanos , Imunoterapia/métodos , Neoplasias/genética , Oligonucleotídeos Antissenso/farmacologia
7.
Exp Hematol ; 24(7): 829-38, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8647234

RESUMO

The "bystander effect" refers to the death of unmodified tumor cells when in contact with ganciclovir (GCV)-exposed, herpes simplex virus-thymidine kinase (HSV-TK)-modified tumor cells. Although the exact mechanism or mechanisms involved in mediating the bystander effect in vivo are unknown, our findings suggest that an intact host immune system is required for the phenomenon to occur. The present study was designed to establish the effect of HSV-TK-modified tumor cells and GCV on the tumor and its microenvironment in vivo. In sublethally irradiated and immunodeficient Balb/c mice, the bystander effect was observed to be diminished or abrogated. Histopathologic examination of the tumor mass from immunocompetent mice demonstrated centralized hemorrhagic tumor necrosis (38%) after inoculation of the HSV-TK-modified tumor cells and GCV in tumor-bearing mice compared with the control mice (5%), indicating that cytokines such as tumor necrosis factor-alpha (TNF-alpha) were being released locally. This hypothesis was underscored using reverse transcriptase polymerase chain reaction (RT-PCR), by the demonstration of cytokine mRNA expression in mice treated with HSV-TK-expressing tumors and GCV. Semiquantitative PCR analysis for TNF-alpha using PCR-MIMIC on tumor samples from mice treated on days 1 and 4 showed a two-fold increase in the level on mRNA expression. Also, immunohistochemical staining for TNF-alpha showed that mononuclear inflammatory cells infiltrating the tumor were its source. Finally, characterization of tumor-infiltrating lymphocytes (TIL) in experimental animals demonstrated a two- to three-fold increase in the number of macrophages and T cells compared with control animals. These results demonstrate that, in vivo, the bystander effect is mediated in part by an antitumor response through the release of cytokines. Further, the cytokine milieu and tumor microenvironment can be modulated following injection of HSV-TK cells and GCV to enhance the host immune response, which is of potential use in clinical trials.


Assuntos
Citocinas/fisiologia , Fibrossarcoma/terapia , Ganciclovir/uso terapêutico , Engenharia Genética , Neoplasias Ovarianas/patologia , Proteínas Recombinantes de Fusão/antagonistas & inibidores , Timidina Quinase/genética , Proteínas Virais/genética , Animais , Citocinas/biossíntese , Citocinas/genética , Feminino , Fibrossarcoma/imunologia , Fibrossarcoma/patologia , Ganciclovir/farmacologia , Regulação Neoplásica da Expressão Gênica , Sobrevivência de Enxerto/imunologia , Sobrevivência de Enxerto/efeitos da radiação , Hemorragia/etiologia , Humanos , Imunocompetência/efeitos da radiação , Linfócitos do Interstício Tumoral/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Necrose , Transplante de Neoplasias , Neoplasias Ovarianas/imunologia , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Lesões por Radiação/complicações , Lesões por Radiação/imunologia , Simplexvirus/enzimologia , Timidina Quinase/antagonistas & inibidores , Células Tumorais Cultivadas/transplante , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/antagonistas & inibidores
8.
Neuroscience ; 290: 421-34, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25637809

RESUMO

The opioid system is involved in infant-mother bonds and adult-adult bonds in many species. We have previously shown that µ opioid receptors (MORs) and κ opioid receptors (KORs) are involved in regulating the adult attachment of the monogamous titi monkey. The present study sought to determine the distribution of MOR and KOR in the titi monkey brain using receptor autoradiography. We used [(3)H][D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin (DAMGO) to label MORs and [(3)H]U69,593 to label KORs. MOR binding was heterogeneous throughout the titi monkey brain. Specifically, MOR binding was observed in the cingulate gyrus (CG), striatum, septal regions, diagonal band, amygdala, hypothalamus, hippocampus, and thalamus. Binding was particularly dense in the septum, medial amygdala, paraventricular nucleus of the hypothalamus, mediodorsal thalamus with moderate binding in the nucleus accumbens. Consistent with other primate species, MOR were also observed in "neurochemically unique domains of the accumbens and putamen" (NUDAPs). In general KOR binding was more homogenous. KORs were primarily found in the CG, striatum, amygdala and hippocampus. Dense KOR binding was observed in the claustrum. Relative MOR and KOR binding in the titi monkey striatum was similar to other humans and primates, but was much lower compared to rodents. Relative MOR binding in the titi monkey hypothalamus was much greater than that found in rodents. This study was the first to examine MOR and KOR binding in a monogamous primate. The location of these receptors gives insight into where ligands may be acting to regulate social behavior and endocrine function.


Assuntos
Encéfalo/metabolismo , Pitheciidae/metabolismo , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/metabolismo , Animais , Autorradiografia , Encéfalo/anatomia & histologia , Feminino , Masculino , Ligação do Par , Pitheciidae/anatomia & histologia , Comportamento Social
9.
Hum Gene Ther ; 9(17): 2641-9, 1998 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-9853530

RESUMO

Malignant mesothelioma is a tumor of the pleura for which there is no satisfactory treatment. It is almost universally fatal, regardless of the stage of the tumor at the time of diagnosis. Current treatment modalities include surgery, chemotherapy, and radiation therapy, although in some series none of these modalities is superior to no treatment at all. Because of the dismal prognosis for patients with malignant mesothelioma, a new mode of treatment is desperately needed. A promising area of research into the treatment of various malignancies is gene therapy. Recent studies have demonstrated the utility of exposing tumor cells to cells transduced to express the Herpes simplex virus gene for thymidine kinase (HSV-tk). By virtue of their expression of HSV-tk, the transduced cells are rendered susceptible to the antiviral drug, ganciclovir (GCV). and nearby tumor cells are killed by a phenomenon termed the bystander effect. In this protocol we propose a Phase I trial to study the safety and determine the maximal tolerated dose of an HSV-tk-transduced ovarian cancer cell line (PA1-STK cells) infused into the pleural cavities of patients with malignant pleural mesothelioma, followed by systemic administration of ganciclovir. The hope is that administration of ganciclovir will result in killing of the HSV-tk transduced ovarian cancer cells as well as the nearby malignant mesothelioma cells. This is a standard dose-escalation protocol.


Assuntos
Terapia Genética , Mesotelioma/terapia , Neoplasias Ovarianas/genética , Protocolos Clínicos , Feminino , Ganciclovir/farmacologia , Terapia Genética/efeitos adversos , Herpesvirus Humano 1/genética , Humanos , Neoplasias Ovarianas/patologia , Pleura , Timidina Quinase/genética , Transdução Genética , Células Tumorais Cultivadas
10.
Neurosci Biobehav Rev ; 21(5): 615-29, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9353795

RESUMO

Over the past two decades, evidence has been accumulating that diffusible molecules, such as growth factors and steroids hormones, play an important part in neural senescence, particularly in the hippocampus. There is also evidence that these molecules do not act as independent signals, but show interrelated regulation and cooperative control over the aging process. Here, we review some of the changes that occur in the hippocampus with age, and the influence of two classes of signaling substances: glucocorticoids and neurotrophins. We also examine the interactions between these substances and how this could influence the aging process.


Assuntos
Envelhecimento/fisiologia , Glucocorticoides/fisiologia , Hipocampo/crescimento & desenvolvimento , Fatores de Crescimento Neural/fisiologia , Animais , Hipocampo/fisiologia , Humanos
11.
Cancer Gene Ther ; 3(6): 373-84, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8988840

RESUMO

The herpes simplex virus thymidine kinase gene (HSV-TK) in combination with ganciclovir (GCV), is currently being used in gene therapy-based clinical trials for cancer treatment. Its therapeutic effect is based on a "bystander effect" whereby HSV-TK gene-modified tumor cells are toxic to nearby unmodified tumor cells when exposed to the antiviral drug GCV. We have recently hypothesized that the in vivo mechanism of this bystander effect is due to alterations in the tumor microenvironment in response to release of cytokines and an infiltration of leukocytes after treatment with HSV-TK gene-modified tumor cells and GCV, which results in tumor regression. Expression of B7, a recently identified costimulatory molecule that is important for T-cell stimulation, has been shown to be modulated by stimulatory cytokines interferon-gamma, tumor necrosis factor-alpha, and inhibited by interleukin-10. In the present study, we investigated whether the cytokines released after HSV-TK and GCV treatment could include the expression of the costimulatory molecules B7-1 and B7-2 and the adhesion molecule (ICAM)-1 in the tumor. Furthermore, we investigated whether this altered environment affected the antitumor properties of host lymphocytes. An in vitro model was developed to establish the effects of HSV-TK gene-modified tumor cells and GCV on tumor infiltrating cells. The murine macrophage cell line (IC21) was exposed to either supernatants or cell lysates collected from a mixture of HSV-TK-transduced (KBALB-STK) and non-transduced (KBALB) murine fibrosarcoma tumor cells previously exposed to GCV (experimental). Immunohistochemical analysis showed a significant expression (P < .0001) of B7-1 and B7-2 post exposure of IC21 cells to either supernatant or lysate. In contrast, the level of expression in IC21 cells exposed to the control lysate or supernatant remained unchanged for B7-1 and B7-2. In vivo analysis for B7-1 and B7-2 expression by immunohistochemistry in tumor tissues from experimental mice receiving HSV-TK gene-modified tumor cells and GCV treatment showed a significant expression of B7.1 (35%, P < .0001) and B7.2 (38.2%, P < .0001) on tumor-infiltrating mononuclear cells. In contrast, tumor-bearing control animals showed low levels of B7-2 expression (5.8%), whereas B7-1 was undetectable, as confirmed by reverse-transcriptase polymerase chain reaction. In addition, a significant up-regulation of ICAM expression (50%) on tumor tissues was observed in the experimental group (P = .0317) as compared with the control group (25%). Furthermore, T cells isolated from experimental mice showed a significant in vitro proliferative response (p = .0202) when exposed to syngeneic tumor cells as compared with the control group. These data demonstrated that the use of HSV-TK gene-modified tumor cells and GCV as a suicide gene in the treatment of an intraperitoneal tumor resulted in the expression of the B7 costimulatory molecules and ICAM-1 adhesion molecule and enhanced proliferative response of host T cells. These findings help to understand the mechanism of tumor cell killing in vivo using HSV-TK gene-modified tumor cells.


Assuntos
Antígeno B7-1/metabolismo , Ganciclovir/farmacologia , Molécula 1 de Adesão Intercelular/metabolismo , Simplexvirus/enzimologia , Timidina Quinase/metabolismo , Animais , Antígeno B7-1/imunologia , Fibrossarcoma , Regulação Neoplásica da Expressão Gênica/genética , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Interleucina-2/metabolismo , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Linfócitos T/metabolismo , Células Tumorais Cultivadas
12.
Cancer Gene Ther ; 6(5): 402-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10505850

RESUMO

The herpes simplex virus thymidine kinase (HSV-TK) gene is being developed in the treatment of many different types of tumors. The HSV-TK gene sensitizes tumor cells to the antiviral drug ganciclovir (GCV) and mediates the bystander effect in which unmodified tumor cells are killed as well. Although this approach has shown a significant antitumor effect, the need to potentiate this therapy exists. The results of this study indicate that recombinant interferon alpha2a (1FNalpha2a) acts synergistically with GCV to kill HSV-TK-expressing PA1 human ovarian tumor cells. Furthermore, it enhances the bystander killing of nearby unmodified tumor cells that do not express the HSV-TK gene. Previous studies have suggested that in vitro and in vivo bystander effects may be mediated by different mechanisms. However, IFNalpha2a enhanced bystander killing in both systems, with the survival of mice bearing preexisting tumors being significantly prolonged when they were treated with IFNalpha2a and HSV-TK/GCV compared with either treatment alone. Mechanism studies have shown that treatment with IFNalpha2a and GCV caused an increase in cells in S phase 24 hours after therapy in the HSV-TK-expressing cells, but the mechanism of action of IFNalpha2a does not seem to be related to an increase in DNA damage, because GCV incorporation was not increased after treatment with IFNalpha2a. These findings suggest that IFNalpha2a may be a useful adjunctive therapy for the HSV-TK/GCV system.


Assuntos
Apoptose/efeitos dos fármacos , Fibrossarcoma/terapia , Ganciclovir/farmacologia , Interferon-alfa/farmacologia , Neoplasias Ovarianas/terapia , Animais , Replicação do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Fibrossarcoma/patologia , Ganciclovir/uso terapêutico , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Ovarianas/patologia , Proteínas Recombinantes , Simplexvirus/enzimologia , Timidina Quinase/genética , Células Tumorais Cultivadas
13.
Semin Oncol ; 23(1): 31-45, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8607030

RESUMO

Gene therapy has now become a standard experimental approach for treating cancers that have failed conventional therapies. As the understanding of the molecular nature of carcinogenesis develops, new approaches are being taken to directly target tumor cells, thus bypassing the difficulties of killing cells that are resistant to chemotherapy and radiation. One emerging gene therapy approach has been through the genetic modification of tumor cells with a suicide gene such as the herpes simplex virus thymidine kinase gene (HSV-TK) and ganciclovir (GCV) therapy. Death of tumor cells modified with the HSV-TK gene leads to killing of unmodified in situ tumor cells in a phenomenon termed the "bystander effect." The basis both for this effect and other gene therapy trials underway for the treatment of cancer will be discussed.


Assuntos
Terapia Genética/métodos , Neoplasias/terapia , Morte Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Simplexvirus/enzimologia , Timidina Quinase/genética
14.
Hum Immunol ; 19(1): 1-6, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2884201

RESUMO

Insulin-dependent diabetes (IDD) is positively associated with HLA-D proteins. A critical question is whether or not sequence differences within the HLA-D coding region are the same or different in diabetics and normal individuals of the same haplotype. We have isolated both DR beta 1 alleles from a Dw4/LD MN2 cDNA library and compared them to DR beta 1 genes isolated from normal individuals of the same Dw phenotype. We found no nucleotide differences in the coding region between the normal and diabetic alleles of DR beta 1 suggesting to us that DNA differences other than the DR beta 1 coding region may account for the observed association of HLA-D and diabetes.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Antígenos HLA-D/genética , Antígenos HLA-DR/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , DNA/genética , Diabetes Mellitus Tipo 1/genética , Humanos , Polimorfismo de Fragmento de Restrição
15.
Hum Immunol ; 20(1): 1-11, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2445717

RESUMO

The extensive Dw polymorphism of HLA-D has, to date, been defined using cumbersome and lengthy techniques involving T-cell proliferative reactions. These techniques have not necessarily provided information about the genotype at any single locus of HLA-D because the products of more than a single locus of HLA-D (e.g., DR beta 1 and DR beta 2 of the DR2 haplotypes and in some cases DQ) can contribute to T-cell proliferation and thus to assignment of Dw phenotype. We have recently reported that DR beta 1 alleles relating to the Dw polymorphism can vary by only a single, or a very few, nucleotide differences; the products of this locus are recognized in allo- and restricted responses. Given the importance of defining this polymorphism, we have used specific oligonucleotides as hybridization probes to differentiate between these very closely related alleles. This approach provides the basis for a rapid method for HLA-D typing which, as additional sequence information becomes available, will likely be generally applicable. In addition, oligonucleotide probing allows definition of a gene transcript from an individual locus of HLA-D rather than the phenotype results provided by Dw typing.


Assuntos
Antígenos HLA-D/genética , Antígenos HLA-DR/genética , Oligonucleotídeos , Polimorfismo Genético , Alelos , Linhagem Celular , Humanos , Linfócitos/imunologia , Hibridização de Ácido Nucleico , RNA/genética
16.
Cancer Lett ; 92(2): 167-74, 1995 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-7600527

RESUMO

We have previously demonstrated that genetically modified syngeneic murine tumor cells (KBALB) expressing the herpes simplex virus thymidine kinase gene (HSV-STK) can kill nearby unmodified tumor cells in the presence of ganciclovir (GCV). The killing was mediated by a 'bystander effect' as evidenced by the prolonged animal survival when syngeneic HSV-TK gene-modified tumor cells were inoculated into mice with an intraperitoneal tumor. In this study we investigated whether irradiated xenogeneic HSV-TK gene-modified tumor cells, a human colon carcinoma cell line (HCT) transfected with the HSV-TK gene, can mediate the 'bystander effect' when used in vitro and in vivo. In vitro experiments indicate that irradiated HSV-TK gene-modified xenogeneic cells (HCT) can mediate a bystander effect on the adjacent cells when the tumor population consisted of as few as 10% of the HSV-TK expressing HCT tumor cells. In vivo, animal survival experiments demonstrate that the xenogeneic gene-modified tumor cells could generate the 'bystander effect' in mice with intraperitoneal tumors as evidenced by prolonged animal survival. In addition, histologic examination of the tumors from experimental animals showed extensive tumor necrosis 3 days post HSV-TK/GCV treatment in comparison to control animals. To evaluate the cause of necrosis in vivo, we assayed for cytokines, which may be involved in mediating this process, by performing RT-PCR and immunohistochemistry on tumor RNA and tumor cells, respectively. Production of IL-1 alpha and IL-6 mRNA within the experimental tumors was observed by RT-PCR. However, mRNA expression for other cytokines including IFN-gamma, IL-2 and IL-4 was not present. Immunohistochemical analysis for IL-1 alpha protein showed reactivity within the infiltrating mononuclear cells indicating the release of this soluble factor. These results indicate that the bystander effect can be generated using irradiated xenogeneic cells both, in vitro and in vivo. Furthermore, this process is mediated by the release of cytokines such as IL-1 alpha, IL-6 which enhances the bystander effect in vivo by immunostimulation.


Assuntos
Comunicação Celular/fisiologia , Ciclo Celular/fisiologia , Terapia Genética , Simplexvirus/enzimologia , Simplexvirus/genética , Timidina Quinase/genética , Proteínas Virais/genética , Animais , Morte Celular/fisiologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Feminino , Fibrossarcoma/genética , Fibrossarcoma/patologia , Fibrossarcoma/terapia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase/métodos , Transcrição Gênica , Transdução Genética , Transplante Heterólogo , Células Tumorais Cultivadas
17.
Hum Pathol ; 28(3): 321-31, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9042797

RESUMO

The host-tumor interaction may play an important role in determining tumor progress. Recent studies have shown that this interaction can be influenced by the release of soluble factors by tumor cells and tumor-infiltrating lymphocytes (TIL). The aim of our study is to characterize the nature of cytokines and growth factors and their relationship to the cellular infiltrates in 16 patients with ovarian cancer using reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry. Total RNA from 20 malignant and 10 benign specimens were used to assay for expression of 12 cytokines. Additionally, monoclonal antibodies (MAbs) were used to detect T cells, CD4+ helper and CD8+ cytotoxic/suppressor T-cell subtypes, B cells, and macrophages. Our results showed the expression of transforming growth factor-beta1 (TGF-beta1), interleukin-10 (IL-10), and granulocyte-macrophage colony-stimulating factor (GM-CSF) in 19, 17, and 10 malignant specimens, P < .001, .001, and .05, respectively. Other cytokines such as interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), TNF-beta/LT, IL-2, and IL-6 were expressed in a few cases, and IL-1alpha and IL-4 expression were not detected. The benign samples did not express IL-10, but GM-CSF, TGF-beta1, and IL-8 were expressed in one, one, and four specimens, respectively. Interestingly, in four cases in which samples from the primary and relapse tumors were available for analysis, the tumors in relapse showed a significant increase for TGF-beta1 (P < .05) and a decreased trend in IL-10 mRNA levels. The source of these factors was tumor cells as detected immunohistochemically. This combined alteration of TGF-beta1 and IL-10 was associated with a significant reduction in number of TIL in general, and CD8+ and macrophages in particular (P = .036 and .049, respectively). Our findings suggest the important role of certain soluble factors in the complex process of tumor progression. Furthermore, understanding the tumor-host relationship and the factors influencing the interaction may be helpful in developing effective and innovative treatment methods.


Assuntos
Citocinas/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Ovarianas/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/secundário , Adulto , Idoso , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Primers do DNA , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/patologia , Neoplasias das Tubas Uterinas/imunologia , Neoplasias das Tubas Uterinas/patologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Imuno-Histoquímica , Interferon gama/metabolismo , Interleucinas/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , RNA/análise , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Am J Clin Pathol ; 103(2): 206-14, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7856564

RESUMO

The diagnostic ability of cytological preparations can be hampered by specimen inadequacy and the presence of representative cells, which may result in a diagnostic accuracy of only 70%. An immunocytochemical battery (ICC), which included anti-p53, anti-c-erbB-2, and B72.3 MoAbs, was used to enhance sensitivity in 87 specimens of body effusions. Thirty-six cases were positive for malignancy using conventional cytology. Forty cases were negative and 11 cases were inconclusive or had an equivocal diagnosis. Sensitivity was 65%, and there was a negative predictive value (NPV) of 62%. p53 was expressed in 50 cases (56%, sensitivity = 83%, NPV = 73%), and B72.3 MoAb was positive in 36 cases (37%, sensitivity = 66%, NPV = 64%). Forty-eight cases (56%) displayed reactivity with anti-c-erbB-2 (sensitivity = 75%, NPV = 63%). The authors concluded that application of an ICC panel of anti-p53, B72.3 and c-erbB-2 to complement conventional cytology increases sensitivity to 98% (P < .0005) with an NPV of 96% (P = .001).


Assuntos
Líquido Ascítico/fisiopatologia , Expressão Gênica , Neoplasias/genética , Oncogenes , Derrame Pleural/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Reações Falso-Negativas , Feminino , Genes erbB-2 , Genes p53 , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Patologia/métodos , Sensibilidade e Especificidade
19.
Hematol Oncol Clin North Am ; 13(1): 109-33, viii, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10080072

RESUMO

Genetic abnormalities of cancer cells are complex and usually nonspecific. Genetic anomalies specific to ovarian cancer have not been reported. This article focuses on what molecular anomalies are known in ovarian cancer and describes the first trials that have used transfer of genes to reestablish a normal cellular function in this disease. Suicide gene therapy has been the prototype of this new therapeutic approach.


Assuntos
Terapia Genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Feminino , Humanos
20.
Physiol Behav ; 63(5): 933-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9618019

RESUMO

Chronic stress has been reported to impair spatial memory and cause hippocampal impairment in rodents. Glucocorticoids are believed to be the active agent in this impairment. Studies have demonstrated that chronic glucocorticoid administration results in animals being impaired in the Morris water maze (MWM) or eight-arm radial maze. Although both of these methods are well established means of testing spatial memory, neither might be considered optimal for studying the behavioral effects of stress. The Morris maze is itself highly stressful to the animals. The eight-arm maze relies on a food reward to motivate the animals, and glucocorticoids have profound effects on hunger and satiety. We therefore investigated behavioral deficits of corticosterone-treated animals in the two previously used mazes and the Barnes circular platform maze (BCM), a test similar in design to the Morris maze, but one that does not require the animal to perform a highly stressful swim. Consistent with results in other tests, we found that animals that had been treated for 3 months with stress-equivalent concentrations of glucocorticoids showed significantly impaired behavior in the Barnes maze.


Assuntos
Nível de Alerta/fisiologia , Corticosterona/fisiologia , Aprendizagem em Labirinto/fisiologia , Rememoração Mental/fisiologia , Retenção Psicológica/fisiologia , Animais , Masculino , Ratos , Ratos Endogâmicos F344
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