Abstract:

Stings by insects from the Hymenoptera order are known to cause life-threatening allergic reactions and impair life quality. Despite the effectiveness of conventional vespid venom immunotherapy, more standardized and safer allergy vaccines are required and recombinant hypoallergenic variants are important clinical tools. Antigen 5 is a major allergen of vespid venoms and it was previously reported that Antigen 5 from Polybia scutellaris (Poly s 5) could be a hypoallergenic variant. In this work we assess the immunological behavior and allergenic activity of Poly s 5 in order to explore its suitability for specific immunotherapy. With this aim, recombinant Poly s 5 was expressed in Pichia pastoris and the presence of cross-reactive epitopes with Pol a 5, a known allergenic Antigen 5, was investigated both at the IgG and IgE levels, by ELISA assays and a basophil-mediator release assay respectively. A molecular model was also built to better understand the relationship between immunological and structural aspects. In mice, Poly s 5 induced IgG antibodies which cross-reacted with Pol a 5. However, Poly s 5 induced only minimal amounts of IgE and was a poor inducer of basophil-mediator release, even when the cells were sensitized with Pol a 5-specific IgE. Moreover, Poly s 5-specific serum showed a specific protective activity and was able to inhibit the Pol a 5-induced basophil degranulation. Structural analysis from the molecular model revealed that a few amino acid substitutions in the N-terminal region of Poly s 5 should lead to an alteration of the surface topography and electrostatic potential of the epitopes which could be responsible for its hypoallergenic behavior. These findings, taken as a whole, show that Poly s 5 is likely a naturally occurring hypoallergenic Antigen 5 variant.

Author affiliation: Vinzon, Sabrina Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-química Biológicas "prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-química Biológicas; Argentina

Author affiliation: Marino, Cristina Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-química Biológicas "prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-química Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina

Author affiliation: Rivera, Elena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; Argentina

Author affiliation: Biscoglio, Mirtha Josefa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-química Biológicas "prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-química Biológicas; Argentina

Abstract:

Functional presence of histamine H4 receptor (H4R) was demonstrated in human melanoma cell lines and biopsies. Objective: The purposes of this work were to investigate signal transduction pathways and biological responses triggered by the activation of H4R in human primary (WM35) and metastatic (M1/15) melanoma cell lines and to evaluate the in vivo antitumor activity of histamine (HA) and clozapine (CLZ) on human M1/15 melanoma xenografts. Methods: Clonogenic assay, incorporation of BrdU, cell cycle distribution, phosphorylation levels of ERK1/2 and cAMP production were evaluated in vitro. An experimental human melanoma model was developed into athymic nude mice. Tumor growth, survival and histochemical studies were performed in order to investigate the expression levels of H4R, HA, PCNA, mitotic index (MI), and angiogenesis. Results: The results indicate that H4R agonists inhibited forskolin-induced cAMP levels only in M1/15 cells while increased phosphorylation levels of ERK1/2 and decreased proliferation in both cell types. In vivo studies show that HA and CLZ (1 mg kg1, sc) significantly increased median survival and decreased tumor volume. These effects were associated to a reduction in MI, in the expression of proliferation marker and in intratumoral neovascularization. Conclusions: We conclude that HA and CLZ exhibit an antitumoral effect in vitro and in vivo on human melanoma, suggesting the therapeutic potential of these compounds for the treatment of malignant melanoma

Author affiliation: Massari, Noelia Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Medina, Vanina Araceli. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Cricco, Graciela Patricia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Martinel Lamas, Diego José. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Sambuco, Lorena Andrea. Instituto de Inmunooncología; Argentina;

Author affiliation: Pagotto, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina;

Author affiliation: Ventura, Clara. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Ciraolo, Pablo Juan. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Pignataro, Omar Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina;

Author affiliation: Bergoc, Rosa Maria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;

Author affiliation: Rivera, Elena Susana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Fisico Matematica. Cat.de Fisica; Argentina;

Abstract:

It is well known the participation of oxidative stress in the induction and development of different pathologies including cancer, diabetes, neurodegeneration and respiratory disorders among others. It has been reported that oxidative stress may be induced by pesticides and it could be the cause of health alteration mediated by pollutants exposure. Large number of registered products containing chlorpyrifos (CPF) is used to control pest worldwide. We have previously reported that 50 μM CPF induces ROS generation and produces cell cycle arrest followed by cell death. The present investigation was designed to identify the pathway involved in CPF-inhibited cell proliferation in MCF-7 and MDA-MB-231 breast cancer cell lines. In addition, we determined if CPF-induced oxidative stress is related to alterations in antioxidant defense system. Finally we studied the molecular mechanisms underlying in the cell proliferation inhibition produced by the pesticide. In this study we demonstrate that CPF (50 μM) induces redox imbalance altering the antioxidant defense system in breast cancer cells. Furthermore, we found that the main mechanism involved in the inhibition of cell proliferation induced by CPF is an increment of p-ERK1/2 levels mediated by H2O2 in breast cancer cells. As PD98059 could not abolish the increment of ROS induced by CPF, we concluded that ERK1/2 phosphorylation is subsequent to ROS production induced by CPF but not the inverse.

Author affiliation: Ventura, Clara. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Author affiliation: Venturino, Andres. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigaciones en Toxicología Ambiental y Agrobiotecnología del Comahue. Laboratorio de Investigaciones Bioquímicas y Químicas del Ambiente | Universidad Nacional del Comahue. Facultad de Ciencias Agrarias. Centro de Investigaciones en Toxicología Ambiental y Agrobiotecnología del Comahue. Laboratorio de Investigaciones Bioquímicas y Químicas del Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. IDEPA - Subsede San Antonio Oeste; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina

Author affiliation: Miret, Noelia Victoria. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Author affiliation: Randi, Andrea Silvana. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Author affiliation: Rivera, Elena Susana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Author affiliation: Nuñez, Mariel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Author affiliation: Cocca, Claudia Marcela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Abstract:

It has reported that many environmental compounds may display estrogenic actions and these findings led to researchers to associate breast cancer risk with the use of some pesticides. The aim of this work was to investigate the effect of chlorpyrifos (CPF) on cell proliferation and the ERα-dependence of this action employing MCF-7 and MDA-MB-231 breast cancer cell lines. We have also analyzed CPF action on the cell cycle distribution and the cyclins that are implicated in G1-S and intra-S checkpoints. Finally, the action on cell death and ROS production were studied. We demonstrated the ability of CPF 0.05 μM to induce cell proliferation through ERα in hormone-dependent breast cancer cells. In contrast, CPF 50 μM induces intra-S arrest modifying checkpoints proteins, through a mechanism that may involve changes in redox balance in MCF-7. In MDA-MB-231, we have found that CPF 50 μM produces an arrest in G2/M phase which could be related to the capacity of the pesticide for binding to tubulin sites altering microtubules polymerization. Altogether, our results provide new evidences on the action of the pesticide CPF as an environmental breast cancer risk factor due to the effects that causes on the mechanisms that modulate breast cell proliferation.

Author affiliation: Ventura, Clara. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Núñez, Mariel Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Miret, Noelia Victoria. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Martinel Lamas, Diego José. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Randi, Andrea Silvana. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Venturino, Andres. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Rivera, Elena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Cocca, Claudia Marcela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Abstract:

Although several reports indicate effects of histamine (HA) on female reproductive functions, scant literature exists to suggest a physiological role of HA in the male gonad. In the present study, we report a dual concentration-dependent effect of HA on steroidogenesis in MA-10 murine Leydig cells and purified rat Leydig cells. Although 1 nM HA can stimulate steroid production and significantly increase the response to LH/hCG in these cells, 10 microM HA exerts an inhibitory effect. We also provide confirming evidence for the existence of functional HRH1 and HRH2 receptors in both experimental models. The use of HRH1 and HRH2 selective agonists and antagonists led us to suggest that HRH2 activation would be largely responsible for stimulation of steroidogenesis, while HRH1 activation is required for inhibition of steroid synthesis. Our results regarding signal transduction pathways associated with these receptors indicate the coupling of HRH2 to the adenylate cyclase system through direct interaction with a Gs protein. Moreover, we show HRH1 activation mediates increases in inositol phosphate production, possibly due to coupling of this receptor to Gq protein and phospholipase C activation. The data compiled in this report clearly indicate that HA can modulate Leydig cell steroidogenesis in the testis and suggest a possible new physiological site of action for HA. Given that many drugs binding to HRH1, HRH2, or both, are widely prescribed for the treatment of diverse HA-related pathologies, it seems necessary to increase the knowledge regarding histaminergic regulation of testicular functions, to avoid possible unexpected side effects of such substances in the testis.

Author affiliation: Mondillo, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina

Author affiliation: Patrignani, Zoraida. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina

Author affiliation: Reche, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina

Author affiliation: Rivera, Elena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Pignataro, Omar Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina

Abstract:

Scleroderma, sclerosis of the skin, is a severe autoimmune disease refractant to all kind of treatments. To study the in vivo effects of a combination of three oligoelements selenium (Se), zinc (Zn), and manganese (Mn) plus Lachesis muta venom (O-LM) on the bleomycin (BLM)-induced scleroderma mouse experimental model. C3H mice were randomly divided into four groups: control (phosphate-buffered saline (PBS)), O-LM, BLM, and BLM + O-LM. All administrations were performed subcutaneously into the back of mice. BLM was injected 5 days per week for three consecutive weeks and O-LM was administered simultaneously with BLM from the beginning of the experiments and lasted for 3 weeks after the final BLM or PBS injection (for O-LM and BLM + O-LM groups), when animals were sacrificed and histopathological, immunohistochemical, thiobarbituric acid reactive species (TBARS) evaluation, and autoantibodies detection were determined. O-LM significantly reduced BLM-induced enhanced dermal thickness (605 ± 47 vs. 956 ± 59 μm, P < 0.01), collagen deposition, and mast cells infiltration (43.1 ± 1.0 vs. 102 ± 14.1 mast cells, P < 0.05). O-LM administration significantly blocked BLM-induced oxidative damage and the enhanced immunoreactive fibroblasts for α-smooth muscle actin while reduced BLM-induced autoantibodies that strongly react mainly with skin and spleen. O-LM significantly reduced BLM-induced scleroderma through the modulation of antioxidant and immunological pathways.

Author affiliation: Crescenti, Eduardo J. V.. Instituto de Inmuno Oncología "Dr. Ernesto J. V. Crescenti"; Argentina

Author affiliation: Medina, Vanina Araceli. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Sambuco, Lorena Andrea. Instituto de Inmuno Oncología "Dr. Ernesto J. V. Crescenti"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Cremaschi, Graciela Alicia. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Genaro, Ana Maria. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Cricco, Graciela P.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Martin, Gabriela Adriana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Valli, Eduardo. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Martinel Lamas, Diego José. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Perazzo Rossini, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentina

Author affiliation: Rivera, Elena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Bergoc, Rosa Maria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Abstract:

The radioprotective potential of histamine on healthy tissue has been previously demonstrated. The aims of this work were to investigate the combinatorial effect of histamine or its receptor ligands and gamma radiation in vitro on the radiobiological response of 2 breast cancer cell lines (MDA-MB-231 and MCF-7), to explore the potential molecular mechanisms of the radiosensitizing action and to evaluate the histamine-induced radiosensitization in vivo in a triple negative breast cancer model. Results indicate that histamine significantly increased the radiosensitivity of MDA-MB-231 and MCF-7 cells. This effect was mimicked by the H1R agonist 2-(3-(trifluoromethyl)phenyl)histamine and the H4R agonists (Clobenpropit and VUF8430) in MDA-MB-231 and MCF-7 cells, respectively. Histamine and its agonists enhanced radiation-induced oxidative DNA damage, DNA double-strand breaks, apoptosis and senescence. These effects were associated with increased production of reactive oxygen species, which correlated with the inhibition of catalase, glutathione peroxidase and superoxide dismutase activities in MDA-MB-231 cells. Histamine was able also to potentiate in vivo the anti-tumoral effect of radiation, increasing the exponential tumor doubling time. We conclude that histamine increased radiation response of breast cancer cells, suggesting that it could be used as a potential adjuvant to enhance the efficacy of radiotherapy.

Author affiliation: Martinel Lamas, Diego José. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Cortina, Jorge E.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Ventura, Clara. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Sterle, Helena Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Valli, Eduardo. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; Argentina

Author affiliation: Balestrasse, Karina Beatriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina

Author affiliation: Blanco, Horacio Alejandro. Gobierno de la Ciudad de Buenos Aires. Hospital Municipal de Oncología "Marie Curie"; Argentina

Author affiliation: Cremaschi, Graciela Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Rivera, Elena Susana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Medina, Vanina Araceli. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Abstract:

Background: Glibenclamide (Gli) binds to the sulphonylurea receptor (SUR) that is a regulatory subunit of ATP-sensitive potassium channels (KATP channels). Binding of Gli to SUR produces the closure of KATP channels and the inhibition of their activity. This drug is widely used for treatment of type 2-diabetes and it has been signaled as antiproliferative in several tumor cell lines. In previous experiments we demonstrated the antitumoral effect of Gli in mammary tumors induced in rats. The aim of the present work was to investigate the effect of Gli on MDA-MB-231 breast cancer cell proliferation and to examine the possible pathways involved in this action. Results: The mRNA expression of the different subunits that compose the KATP channels was evaluated in MDA-MB-231 cells by reverse transcriptase-polymerase chain reaction. Results showed the expression of mRNA for both pore-forming isoforms Kir6.1 and Kir6.2 and for the regulatory isoform SUR2B in this cell line. Gli inhibited cell proliferation assessed by a clonogenic method in a dose dependent manner, with an increment in the population doubling time. The KATP channel opener minoxidil increased clonogenic proliferation, effect that was counteracted by Gli. When cell cycle analysis was performed by flow cytometry, Gli induced a significant cell-cycle arrest in G0/G1 phase, together with an up-regulation of p27 levels and a diminution in cyclin E expression, both evaluated by immunoblot. However, neither differentiation evaluated by neutral lipid accumulation nor apoptosis assessed by different methodologies were detected. The cytostatic, non toxic effect on cell proliferation was confirmed by removal of the drug. Combination treatment of Gli with tamoxifen or doxorubicin showed an increment in the antiproliferative effect only for doxorubicin. Conclusions: Our data clearly demonstrated a cytostatic effect of Gli in MDA-MB-231 cells that may be mediated through KATP channels, associated to the inhibition of the G1-S phase progression. In addition, an interesting observation about the effect of the combination of Gli with doxorubicin leads to future research for a potentialnovel role for Gli as an adjuvant in breast cancer treatment.

Author affiliation: Nuñez, Mariel Alejandra. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Medina, Vanina Araceli. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Cricco, Graciela Patricia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Croci, Máximo. Instituto de Inmuno Oncología "Dr. Ernesto J. V. Crescenti"; Argentina

Author affiliation: Cocca, Claudia Marcela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Rivera, Elena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Bergoc, Rosa Maria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Instituto Universidad de la Fundación "Héctor Barceló"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Martin, Gabriela Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Abstract:

Breast cancer is the second most common cancer worldwide, and the leading cause of cancer death in women. Several studies underlined the critical role of histamine in breast cancer development and progression. This review addresses the latest evidence regarding the involvement of histamine and histamine receptors in breast cancer, focusing particularly in the histamine H4 receptor (H4R). Histamine concentration in breast cancer tissues was found to be higher than that in normal tissues of healthy controls by means of an increase in the activity of histidine decarboxylase (HDC), the enzyme involved in histamine production. The expression of H4R in different experimental models and human biopsies, the associated biological responses, as well as the in vivo treatment of experimental tumors with H4R ligands is reviewed. Evidence demonstrates that the H4R exhibits a key role in histamine-mediated biological processes such as cell proliferation, senescence and apoptosis in breast cancer. The polymorphisms of the H4R and HDC genes and their association with breast cancer risk and malignancy reinforce the critical (patho)physiological role of H4R in breast cancer. In addition, H4R agonists display anti-tumor effects in vivo in a triple negative breast cancer model. The findings support the exploitation of the H4R as a molecular target for breast cancer drug development.

Author affiliation: Martinel Lamas, Diego José. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisotopos; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Author affiliation: Rivera, Elena Susana. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisotopos; Argentina

Author affiliation: Medina, Vanina Araceli. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisotopos; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina

Abstract:

Since histamine discovery in 1910, it has been recognized as a major mediator in gastric acid secretion and inflammation that is a main pathophysiological characteristic of allergy. For many years, drug development and therapeutic application of histamine antagonists were mainly focused on the allergic and gastrointestinal diseases. At present, it is one of the monoamines (2-(imidazol-4-yl)ethylamine) with the broadest spectrum of activities in various physiological and pathological situations. Thus, it has been shown to be involved in aminergic neurotransmission and numerous brain functions including learning, memory, sleep/wakefulness, locomotor activity, nociception, food intake, secretion of pituitary hormones, and regulation of gastrointestinal and circulatory functions, as well as modulation of immunity and hematopoiesis. A significant body of research has contributed to the elucidation of the functional capacities of histamine in tumor cell growth and development. Evidences for multiple cellular sources of histamine, the discovery of a novel histamine receptor (H4R) and the demonstration of a histamine – cytokine cross-talk have modified the perspective which suggests new potential therapeutic uses of histamine and its receptor ligands. The involvement of histamine in cancer immunotherapy has been a subject of interest for more than a decade. Histamine dihydrochloride is being safely used in clinical trials as an adjuvant for the potential treatment of different cancers, improving efficacy by increasing survival benefit and exhibiting no unexpected or irreversible side effects. Interleukin-2 and interferon-alpha have been used as therapeutic options for the treatment of certain malignancies such as metastatic malignant melanoma, myelogenous leukemia, renal cell carcinoma and chronic hepatitis C. Combination therapy with histamine has two key advantages over cytokine therapy alone, namely improved cytotoxicity against a greater range of cancer types, and improved quality-of-life as a consequence of lower dose administration of the cytokines. Furthermore, radiation therapy is a well recognized treatment modality for cancer. Although effective, adverse effects due to radiotherapy are unavoidable, even with localized delivery techniques. Regardless of many years of research, there are surprisingly few radiation protectors in use today, whose clinical use is limited due to their toxicity; thus, the development of effective and nontoxic agents is yet a challenge for oncologists and radiobiologists. We have recently reported that histamine significantly protects two of the most radiosensitive tissues, small intestine and bone marrow, from high doses of radiation. In addition, histamine has the ability to prevent functional and histological alterations of salivary glands exerted by ionizing radiation. These features make histamine a suitable candidate for its use as an adjuvant for cancer immunotherapy and also as a selective radioprotector for patients undergoing radiotherapy. In the present review we aimed to briefly summarize some general notions on histamine functions before focusing on some recent evidence supporting the novel role of histamine in the immune function and the potential application as an adjuvant to tumor immunotherapy and radiotherapy.

Author affiliation: Medina, Vanina Araceli. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina

Author affiliation: Rivera, Elena S.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina