antonia aranega - Academia.edu (original) (raw)

Papers by antonia aranega

Cytotherapy, 2010

Background aims. The goal was to induce the transdifferentiation (or conversion) of human adipose... more Background aims. The goal was to induce the transdifferentiation (or conversion) of human adipose-derived stem cells to cardiomyocytes using an intracellular extract obtained from adult human heart tissue. Methods. Human adult stem cells from lipoaspirates were transiently permeabilized, exposed to human atrial extracts and allowed to recover in culture. Results. After 21 days, the cells acquired a cardiomyocyte phenotype, as demonstrated by morphologic changes (appearance of binucleate, striated cells and branching fi bers), immunofl uorescence detection of cardiac-specifi c markers (connexin-43, sarcomeric a-actinin, cardiac troponin I and T, and desmin) and the presence of cardiomyocyte-related genes analyzed by reverse transcription-polymerase chain reaction (cardiac myosin light chain 1, a-cardiac actin, cardiac troponin T and cardiac b-myosin). Conclusions. We have demonstrated for the fi rst time that adult cardiomyocytes obtained from human donors retain the capacity to induce cardiomyocyte differentiation of mesenchymal stromal cells. The use of autologous extracts for reprogramming adult stem cells may have potential therapeutic implications for treating heart disease.

Biomedicine & Pharmacotherapy, 2012

The potential use of gene therapy to improve the response of patients with advanced cancer is bei... more The potential use of gene therapy to improve the response of patients with advanced cancer is being intensively analyzed. We evaluated the cytotoxic impact of the gef gene, a suicide gene, which has a demonstrated antiproliferative activity in tumor cells, in colon carcinoma cells in order to improve the antitumour effect of chemotherapeutic drugs used as first line treatment in the management of advanced colon cancer. We found that the gef gene induced a marked decrease in cell viability (50% in 24h) in T-84 cells through cell death by apoptosis. Interestingly, when gef gene expression was combined with drugs of choice in the clinical treatment of colon cancer (5-fluorouracil, oxaliplatin and irinotecan), a strong synergistic effect was observed with approximately a 15-20% enhancement of the antiproliferative effect. Our data demonstrate, for the first time, that gef gene expression induces significant growth arrest in colon cancer cells and that it is able to enhance the effect of some cytotoxic drugs compared with a single therapeutic approach. These results indicate the potential therapeutic value of the gef gene in colon cancer combination therapy.

Archives of Medical Science, 2016

Introduction: Recently, we have reported the antitumor properties of a new family of synthetic me... more Introduction: Recently, we have reported the antitumor properties of a new family of synthetic merosesquiterpenes, among which meroxest is highlighted, since it has high activity and specificity for ER + breast cancer cells. In this paper, we characterize allografts of ER + E0771 mouse breast tumor cells in immunocompetent C57BL/6 mice, and also analyze the effect of meroxest on the prognosis of the disease. Material and methods: Twenty female C57BL/6 mice were injected with 10 6 E0771 cells. Once the tumors reached the appropriate size, the mice were divided into two groups, one control and another treated orally with 15 mg/ kg of meroxest. After 20 days, tumor samples were taken for histopathological study and for determination of the expression of the prognostic markers Ki67 and vascular endothelial growth factor (VEGF) by immunofluorescence. Results: In sections stained with hematoxylin-eosin, we observed that tumors have a well-defined capsule enclosing E0771 tumor cells. The central area of tumors contains necrotic regions with leukocyte infiltration. Meroxest treatment significantly reduces tumor size (68%, p < 0.05), induces changes in its structure, decreases the degree of leukocyte infiltration, and significantly reduces the expression of Ki67 (33%, p < 0.05) and VEGF (82%, p < 0.05). Conclusions: Meroxest improves the prognosis of mice since it reduces leukocyte infiltration, and decreases the expression of Ki67 and VEGF markers. Consequently, the merosesquiterpene could become a useful antiangiogenic drug in the treatment of breast cancer. These results encourage us to deepen the study of meroxest, in order to find more evidence that supports the convenience of its evaluation in a clinical study or trial.

Oxidative Medicine and Cellular Longevity, 2016

The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs ... more The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesizedde novo(endogenous) or incorporated through the diet and nutritional supplements (exogenous). In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even prot...

European Journal of Anatomy

Anatomy has been classically considered as a basic foundation for the teaching of medicine, devel... more Anatomy has been classically considered as a basic foundation for the teaching of medicine, developing a decisive role in medical education and for future professional activity. But, in common with other scientific disciplines, it has grown simultaneously with technology and communication sciences and in a much prescribed manner. The purpose of our study was to estimate different parameters related to the quality of the anatomical teaching at the University of Granada. In trying to achieve this, we have focused on the Human Anatomy I and II courses (given in the first and second years of the medical degree respectively). Once the examinations in these courses were completed, a questionnaire was filled by the students in which they had to estimate, in a one to five range, the adaptation and the adjustment of different aspects related to the development of the course. The results indicated that the students were in favour of practical classes compared to theoretical tuition. On the other hand, the pedagogical organisation of the courses was highly valued by the students, particularly in relation to the adaptation of programme objectives and to the recommended bibliography (both for textbooks and atlases). The best estimated didactic resource for the practical aspect of the subject was the use of human anatomical specimens, and the most favoured procedure in the theoretical classes was the use of the blackboard. For the examinations and assessments, no special preference for any evaluation method was found, but the use of complementary papers (e.g. use of monographs, oral expositions) was considered by the students to be of very little importance.

European Journal of Anatomy

A crucial problem in neurobiology is how neurons are able to maintain neurotransmitter receptors ... more A crucial problem in neurobiology is how neurons are able to maintain neurotransmitter receptors at specific membrane domains. The large structural heterogeneity of gamma aminobutyric acid receptors (GABA A Rs) led to the hypothesis that there could be a link between GABA A R gene diversity and the targeting properties of the receptor complex. Previous studies using Fluorescence Recovery After Photobleaching (FRAP) have shown a restricted mobility in GABA A Rs containing the a1 subunit. The M3/M4 cytoplasmic loop is the region of the a1 subunit with the lowest sequence homology to other subunits. Therefore, we asked whether the M3/M4 loop is involved in cytoskeletal anchoring and GABA A R clustering. A series of a1 chimeric subunits was constructed: a1CH (control subunit), a1CD (Cytoplasmic loop deleted), a1CD2, and a1CD3 (a1 with the M3/ M4 loop from the a2 and a3 subunits, respectively). Our results using FRAP indicate an involvement of the M3/M4 cytoplasmic loop of the a1 subunit in controlling receptor lateral mobility. On the other hand, inmunocytochemical approaches showed that this domain is not involved in subunit targeting to the cell surface, subunit-subunit assembly, or receptor aggregation.

International Journal of Oncology, 2010

The E gene from ºX174 encodes a membrane protein with a toxic domain that leads to a decrease in ... more The E gene from ºX174 encodes a membrane protein with a toxic domain that leads to a decrease in the tumour cell growth rate. With the aim of improving the antitumour effect on lung and colon cancer cells of the currently used chemotherapeutic drugs such as gemcitabine, carboplatin and paclitaxel, and 5-fluorouracil (5FU) plus folinic acid (FA) with irinotecan or oxaliplatine, we investigated a new combined therapy using these drugs associated to the transfection of E gene. Our results showed that E gene was able to decrease proliferation rate in A-549 and T-84 cells by inducing apoptotic the mitochondrial pathway. Significantly greater inhibition of proliferation was obtained using drugs in combination with E gene in comparison to single-agent treatments or controls. E gene combined with paclitaxel had the greatest effect on A-549 cells and combined with 5FU/FA/oxaliplatin on T-84 cells. Antitumour mechanisms of the chemotherapeutic drugs were enhanced by E gene, which itself has direct oncolytic effects inducing A-549 and T-84 apoptosis. Our in vitro results indicate that the combined therapy of E gene and cytotoxic drugs may be of potential therapeutic value as a new strategy for patients with advanced lung and colon cancer.

International Journal of Oncology, 2008

The low efficiency of conventional therapies in achieving long-term survival of lung cancer patie... more The low efficiency of conventional therapies in achieving long-term survival of lung cancer patients calls for development of novel options. The potential use of combined gene therapy is under intensive study. One approach uses the expression of genes encoding cytotoxic proteins that affect cellular viability. The gef gene from E. coli, identified as a member of a gene family encoding homologous cell-killing functions, encodes for a membrane protein with a toxic domain which leads to a decrease in the rate of tumour cell growth. To improve the antitumoral effect of the paclitaxel in lung cancer cells, we investigated a combined suicide gene therapy using this drug and gef gene in vitro, using A-549 lung cancer cells in culture and forming multicellular tumour spheroids (MTS). Our results showed that gef expression in A-549 cells led to an ultrastructural changes, including dilated mitochondria with clear matrices and disrupted cristae and cell surface alterations such as reduction in length and number of microvilli and cytoplasmic membrane evaginations. The use of paclitaxel in A-549 lung cancer cells transfected with gef gene enhanced the chemotherapeutic effect of this drug. Volume analyses showed an 87.4% decrease in the A-549 MTS growth after 96 h in comparison with control MTS. This inhibition was greater than that obtained using the gene therapy or chemotherapy alone. In conclusion, gef gene has a cytotoxic effect in lung cancer cells and enhances cell growth inhibition when used with paclitaxel. These results indicate that this combined therapy may be of potential therapeutic value in lung cancer.

The Journal of nutrition, 2007

Exogenous nucleotides are considered semiessential nutritional components that play an important ... more Exogenous nucleotides are considered semiessential nutritional components that play an important role in intestinal development, maintenance, and recovery from tissue damage. Nucleosides (NS) are the best-absorbed chemical form of nucleotides in the intestinal epithelium. The aim of this work was to clarify, at the cellular level, the effects described in vivo. Under conditions of high intracellular availability of NS, we studied the effects of 2 NS mixtures on the NS uptake and intracellular distribution and on the proliferation, morphology, viability, and cell-cycle phase distribution of rat intestinal epithelial cell line 6. Purine and pyrimidine NS showed a similar uptake profile, but the intracellular incorporation of guanosine was greater than that of uridine, without differences in intracellular distribution. Proliferation assays demonstrated that IEC-6 cell proliferation is increased by a mixture containing thymidine but decreased by one containing uridine. In fact, the anti...

International journal of molecular sciences, 2011

Nanotechnology, along with related concepts such as nanomaterials, nanostructures and nanoparticl... more Nanotechnology, along with related concepts such as nanomaterials, nanostructures and nanoparticles, has become a priority area for scientific research and technological development. Nanotechnology, i.e., the creation and utilization of materials and devices at nanometer scale, already has multiple applications in electronics and other fields. However, the greatest expectations are for its application in biotechnology and health, with the direct impact these could have on the quality of health in future societies. The emerging discipline of nanomedicine brings nanotechnology and medicine together in order to develop novel therapies and improve existing treatments. In nanomedicine, atoms and molecules are manipulated to produce nanostructures of the same size as biomolecules for interaction with human cells. This procedure offers a range of new solutions for diagnoses and "smart" treatments by stimulating the body's own repair mechanisms. It will enhance the early diagn...

International Journal of Molecular Sciences, 2011

Breast cancer research has developed rapidly in the past few decades, leading to longer survival ... more Breast cancer research has developed rapidly in the past few decades, leading to longer survival times for patients and opening up the possibility of developing curative treatments for advanced breast cancer. Our increasing knowledge of the biological pathways associated with the progression and development of breast cancer, alongside the failure of conventional treatments, has prompted us to explore gene therapy as an alternative therapeutic strategy. We previously reported that gef gene from E. coli has shown considerable cytotoxic effects in breast cancer cells. However, its action mechanism has not been elucidated. Indirect immunofluorescence technique using flow cytometry and immunocytochemical analysis were used to detect breast cancer markers: estrogen (ER) and progesterone (PR) hormonal receptors, human epidermal growth factor receptor-2 proto-oncogene (c-erbB-2), ki-67 antigen and p53 protein. gef gene induces an increase in ER and PR expressions and a decrease in ki-67 and c-erbB-2 gene expressions, indicating a better prognosis and response to treatment and a longer disease-free interval and survival. It

Revista Española de Cardiología (English Edition), 2011

Stem Cell Research, 2013

Human adipose derived stem cells (hASCs) can be easily isolated and their plasticity has been wel... more Human adipose derived stem cells (hASCs) can be easily isolated and their plasticity has been well characterized. Several TGF-β superfamily ligands can direct hASCs towards chondrocytes. However, these ligands are difficult to purify and expensive. We have developed a library of Activin/BMP2 chimeric ligands (AB2 ligands) by systematically mixing their sequence segments and have tested their chondrogenic potential in hASCs. Cells cultured in monolayer or in a pellet culture system were incubated with a chemically defined medium supplemented with the chimeric ligands for 4 or 6 weeks and showed higher expression levels of type II collagen, aggrecan, and Sox9 mRNAs when compared with control and non-treated cells. Moreover, toluidine blue, alcian blue, and Masson's trichrome staining was markedly increased in treated cells, both in cell pellet and monolayer assays. In addition, immunohistochemical staining for detection of type I collagen, type II collagen, and Sox 9 demonstrated the acquisition of a chondrogenic phenotype in both culture systems. We present here an inexpensive and robust protocol for differentiation of hASCs towards chondrocytes in a reproducible and highly efficient manner. The AB2 ligands employed are easily produced and have properties that may become useful in cell therapy.

European Journal of …, 2012

PLoS ONE, 2011

The chemotherapeutic drug 5-FU is widely used in the treatment of a range of cancers, but resista... more The chemotherapeutic drug 5-FU is widely used in the treatment of a range of cancers, but resistance to the drug remains a major clinical problem. Since defects in the mediators of apoptosis may account for chemo-resistance, the identification of new targets involved in 5-FU-induced apoptosis is of main clinical interest. We have identified the ds-RNA-dependent protein kinase (PKR) as a key molecular target of 5-FU involved in apoptosis induction in human colon and breast cancer cell lines. PKR distribution and activation, apoptosis induction and cytotoxic effects were analyzed during 5-FU and 5-FU/IFNa treatment in several colon and breast cancer cell lines with different p53 status. PKR protein was activated by 5-FU treatment in a p53-independent manner, inducing phosphorylation of the protein synthesis translation initiation factor eIF-2a and cell death by apoptosis. Furthermore, PKR interference promoted a decreased response to 5-FU treatment and those cells were not affected by the synergistic antitumor activity of 5-FU/IFNa combination. These results, taken together, provide evidence that PKR is a key molecular target of 5-FU with potential relevance in the clinical use of this drug.

European Journal of …, 2012

Development of the European Higher Education Area is linked to the adoption of a new educational ... more Development of the European Higher Education Area is linked to the adoption of a new educational model. Thus, in the Health Sciences, basic science knowledge must be integrated with the clinical skills that students will require in their professional activity. The Anatomy and Embryology Teaching Investigation Group at our university (UGR-N-40-UCUA) designed a specific questionnaire to analyse specific items that affect Anatomy learning. It also developed a teaching methodology for the acquisition of anatomic knowledge, integrating theory and practice, including individual and collective tasks for students and leading to future self-learning. Analyses were performed in different groups of first-year students at the

Journal of Translational Medicine, 2012

Background The CD133 antigen is a marker of radio- and chemo-resistant stem cell populations in g... more Background The CD133 antigen is a marker of radio- and chemo-resistant stem cell populations in glioblastoma (GBM). The O6-methylguanine DNA methyltransferase (MGMT) enzyme is related with temozolomide (TMZ) resistance. Our propose is to analyze the prognostic significance of the CD133 antigen and promoter methylation and protein expression of MGMT in a homogenous group of GBM patients uniformly treated with radiotherapy and TMZ. The possible connection between these GBM markers was also investigated. Methods Seventy-eight patients with GBM treated with radiotherapy combined with concomitant and adjuvant TMZ were analyzed for MGMT and CD133. MGMT gene promoter methylation was determined by methylation-specific polymerase chain reaction after bisulfite treatment. MGMT and CD133 expression was assessed immunohistochemically using an automatic quantification system. Overall and progression-free survival was calculated according to the Kaplan–Meier method. Results The MGMT gene promoter...

International Journal of Cancer, 1998

Classical cytotoxic treatment of rhabdomyosarcoma (RMS) is accompanied often by significant morbi... more Classical cytotoxic treatment of rhabdomyosarcoma (RMS) is accompanied often by significant morbidity and poor response. The use of cytotoxic agents may induce a multidrug resistance phenotype, which plays an important role in the sensitivity of tumoral cells to drugs. Using actinomycin D, a drug of choice in the treatment of RMS, we induced resistance in the TE.32.7 human RMS cell line. The TE.32.7-DACresistant cell line exhibited cross-resistance to vincristine and doxorubicin and showed mdr1/P-glycoprotein over-expression, suggesting that this mechanism was involved in the reduction in intracellular drug concentration and may be responsible for the failure of treatment of RMS with classical cycles of cytotoxics. Furthermore, this resistant cell line showed increased expression of the muscle differentiation markers desmin and ␣-actinin and ultrastructural changes which clearly indicated myogenic differentiation. Our findings suggest that, although this tumor is probably arrested along the normal myogenic pathway to maturation, induction of cell differentiation with anti-neoplastic drugs may be an alternative therapeutic approach. However, the failure of TE.32.7-DAC cells to completely re-enter the program of myogenic differentiation supports the hypothesis that multidrug resistance is a major obstacle in differentiation therapy for RMS.

Experimental Dermatology, 2010

Novel treatment modalities, including gene therapy, are needed for patients with advanced melanom... more Novel treatment modalities, including gene therapy, are needed for patients with advanced melanoma. We evaluated whether the gef gene, a suicide gene from Escherichia coli, had a significant cytotoxic impact on melanoma in vivo. First, we used a non-viral gene delivery approach (pcDNA3.1/ge/) to study the inhibition of melanoma cells (B16-F10) proliferation in vitro. Secondly, we used direct intra-tumoral injection of pcDNA3.1/ge/ complexed with jetPEI to deliver gef cDNA to rapidly growing murine melanomas. We demonstrated that gef gene not only has an antiproliferative effect on B16-F10 cells in vitro, but also

Cytotherapy, 2010

Background aims. The goal was to induce the transdifferentiation (or conversion) of human adipose... more Background aims. The goal was to induce the transdifferentiation (or conversion) of human adipose-derived stem cells to cardiomyocytes using an intracellular extract obtained from adult human heart tissue. Methods. Human adult stem cells from lipoaspirates were transiently permeabilized, exposed to human atrial extracts and allowed to recover in culture. Results. After 21 days, the cells acquired a cardiomyocyte phenotype, as demonstrated by morphologic changes (appearance of binucleate, striated cells and branching fi bers), immunofl uorescence detection of cardiac-specifi c markers (connexin-43, sarcomeric a-actinin, cardiac troponin I and T, and desmin) and the presence of cardiomyocyte-related genes analyzed by reverse transcription-polymerase chain reaction (cardiac myosin light chain 1, a-cardiac actin, cardiac troponin T and cardiac b-myosin). Conclusions. We have demonstrated for the fi rst time that adult cardiomyocytes obtained from human donors retain the capacity to induce cardiomyocyte differentiation of mesenchymal stromal cells. The use of autologous extracts for reprogramming adult stem cells may have potential therapeutic implications for treating heart disease.

Biomedicine & Pharmacotherapy, 2012

The potential use of gene therapy to improve the response of patients with advanced cancer is bei... more The potential use of gene therapy to improve the response of patients with advanced cancer is being intensively analyzed. We evaluated the cytotoxic impact of the gef gene, a suicide gene, which has a demonstrated antiproliferative activity in tumor cells, in colon carcinoma cells in order to improve the antitumour effect of chemotherapeutic drugs used as first line treatment in the management of advanced colon cancer. We found that the gef gene induced a marked decrease in cell viability (50% in 24h) in T-84 cells through cell death by apoptosis. Interestingly, when gef gene expression was combined with drugs of choice in the clinical treatment of colon cancer (5-fluorouracil, oxaliplatin and irinotecan), a strong synergistic effect was observed with approximately a 15-20% enhancement of the antiproliferative effect. Our data demonstrate, for the first time, that gef gene expression induces significant growth arrest in colon cancer cells and that it is able to enhance the effect of some cytotoxic drugs compared with a single therapeutic approach. These results indicate the potential therapeutic value of the gef gene in colon cancer combination therapy.

Archives of Medical Science, 2016

Introduction: Recently, we have reported the antitumor properties of a new family of synthetic me... more Introduction: Recently, we have reported the antitumor properties of a new family of synthetic merosesquiterpenes, among which meroxest is highlighted, since it has high activity and specificity for ER + breast cancer cells. In this paper, we characterize allografts of ER + E0771 mouse breast tumor cells in immunocompetent C57BL/6 mice, and also analyze the effect of meroxest on the prognosis of the disease. Material and methods: Twenty female C57BL/6 mice were injected with 10 6 E0771 cells. Once the tumors reached the appropriate size, the mice were divided into two groups, one control and another treated orally with 15 mg/ kg of meroxest. After 20 days, tumor samples were taken for histopathological study and for determination of the expression of the prognostic markers Ki67 and vascular endothelial growth factor (VEGF) by immunofluorescence. Results: In sections stained with hematoxylin-eosin, we observed that tumors have a well-defined capsule enclosing E0771 tumor cells. The central area of tumors contains necrotic regions with leukocyte infiltration. Meroxest treatment significantly reduces tumor size (68%, p < 0.05), induces changes in its structure, decreases the degree of leukocyte infiltration, and significantly reduces the expression of Ki67 (33%, p < 0.05) and VEGF (82%, p < 0.05). Conclusions: Meroxest improves the prognosis of mice since it reduces leukocyte infiltration, and decreases the expression of Ki67 and VEGF markers. Consequently, the merosesquiterpene could become a useful antiangiogenic drug in the treatment of breast cancer. These results encourage us to deepen the study of meroxest, in order to find more evidence that supports the convenience of its evaluation in a clinical study or trial.

Oxidative Medicine and Cellular Longevity, 2016

The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs ... more The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesizedde novo(endogenous) or incorporated through the diet and nutritional supplements (exogenous). In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even prot...

European Journal of Anatomy

Anatomy has been classically considered as a basic foundation for the teaching of medicine, devel... more Anatomy has been classically considered as a basic foundation for the teaching of medicine, developing a decisive role in medical education and for future professional activity. But, in common with other scientific disciplines, it has grown simultaneously with technology and communication sciences and in a much prescribed manner. The purpose of our study was to estimate different parameters related to the quality of the anatomical teaching at the University of Granada. In trying to achieve this, we have focused on the Human Anatomy I and II courses (given in the first and second years of the medical degree respectively). Once the examinations in these courses were completed, a questionnaire was filled by the students in which they had to estimate, in a one to five range, the adaptation and the adjustment of different aspects related to the development of the course. The results indicated that the students were in favour of practical classes compared to theoretical tuition. On the other hand, the pedagogical organisation of the courses was highly valued by the students, particularly in relation to the adaptation of programme objectives and to the recommended bibliography (both for textbooks and atlases). The best estimated didactic resource for the practical aspect of the subject was the use of human anatomical specimens, and the most favoured procedure in the theoretical classes was the use of the blackboard. For the examinations and assessments, no special preference for any evaluation method was found, but the use of complementary papers (e.g. use of monographs, oral expositions) was considered by the students to be of very little importance.

European Journal of Anatomy

A crucial problem in neurobiology is how neurons are able to maintain neurotransmitter receptors ... more A crucial problem in neurobiology is how neurons are able to maintain neurotransmitter receptors at specific membrane domains. The large structural heterogeneity of gamma aminobutyric acid receptors (GABA A Rs) led to the hypothesis that there could be a link between GABA A R gene diversity and the targeting properties of the receptor complex. Previous studies using Fluorescence Recovery After Photobleaching (FRAP) have shown a restricted mobility in GABA A Rs containing the a1 subunit. The M3/M4 cytoplasmic loop is the region of the a1 subunit with the lowest sequence homology to other subunits. Therefore, we asked whether the M3/M4 loop is involved in cytoskeletal anchoring and GABA A R clustering. A series of a1 chimeric subunits was constructed: a1CH (control subunit), a1CD (Cytoplasmic loop deleted), a1CD2, and a1CD3 (a1 with the M3/ M4 loop from the a2 and a3 subunits, respectively). Our results using FRAP indicate an involvement of the M3/M4 cytoplasmic loop of the a1 subunit in controlling receptor lateral mobility. On the other hand, inmunocytochemical approaches showed that this domain is not involved in subunit targeting to the cell surface, subunit-subunit assembly, or receptor aggregation.

International Journal of Oncology, 2010

The E gene from ºX174 encodes a membrane protein with a toxic domain that leads to a decrease in ... more The E gene from ºX174 encodes a membrane protein with a toxic domain that leads to a decrease in the tumour cell growth rate. With the aim of improving the antitumour effect on lung and colon cancer cells of the currently used chemotherapeutic drugs such as gemcitabine, carboplatin and paclitaxel, and 5-fluorouracil (5FU) plus folinic acid (FA) with irinotecan or oxaliplatine, we investigated a new combined therapy using these drugs associated to the transfection of E gene. Our results showed that E gene was able to decrease proliferation rate in A-549 and T-84 cells by inducing apoptotic the mitochondrial pathway. Significantly greater inhibition of proliferation was obtained using drugs in combination with E gene in comparison to single-agent treatments or controls. E gene combined with paclitaxel had the greatest effect on A-549 cells and combined with 5FU/FA/oxaliplatin on T-84 cells. Antitumour mechanisms of the chemotherapeutic drugs were enhanced by E gene, which itself has direct oncolytic effects inducing A-549 and T-84 apoptosis. Our in vitro results indicate that the combined therapy of E gene and cytotoxic drugs may be of potential therapeutic value as a new strategy for patients with advanced lung and colon cancer.

International Journal of Oncology, 2008

The low efficiency of conventional therapies in achieving long-term survival of lung cancer patie... more The low efficiency of conventional therapies in achieving long-term survival of lung cancer patients calls for development of novel options. The potential use of combined gene therapy is under intensive study. One approach uses the expression of genes encoding cytotoxic proteins that affect cellular viability. The gef gene from E. coli, identified as a member of a gene family encoding homologous cell-killing functions, encodes for a membrane protein with a toxic domain which leads to a decrease in the rate of tumour cell growth. To improve the antitumoral effect of the paclitaxel in lung cancer cells, we investigated a combined suicide gene therapy using this drug and gef gene in vitro, using A-549 lung cancer cells in culture and forming multicellular tumour spheroids (MTS). Our results showed that gef expression in A-549 cells led to an ultrastructural changes, including dilated mitochondria with clear matrices and disrupted cristae and cell surface alterations such as reduction in length and number of microvilli and cytoplasmic membrane evaginations. The use of paclitaxel in A-549 lung cancer cells transfected with gef gene enhanced the chemotherapeutic effect of this drug. Volume analyses showed an 87.4% decrease in the A-549 MTS growth after 96 h in comparison with control MTS. This inhibition was greater than that obtained using the gene therapy or chemotherapy alone. In conclusion, gef gene has a cytotoxic effect in lung cancer cells and enhances cell growth inhibition when used with paclitaxel. These results indicate that this combined therapy may be of potential therapeutic value in lung cancer.

The Journal of nutrition, 2007

Exogenous nucleotides are considered semiessential nutritional components that play an important ... more Exogenous nucleotides are considered semiessential nutritional components that play an important role in intestinal development, maintenance, and recovery from tissue damage. Nucleosides (NS) are the best-absorbed chemical form of nucleotides in the intestinal epithelium. The aim of this work was to clarify, at the cellular level, the effects described in vivo. Under conditions of high intracellular availability of NS, we studied the effects of 2 NS mixtures on the NS uptake and intracellular distribution and on the proliferation, morphology, viability, and cell-cycle phase distribution of rat intestinal epithelial cell line 6. Purine and pyrimidine NS showed a similar uptake profile, but the intracellular incorporation of guanosine was greater than that of uridine, without differences in intracellular distribution. Proliferation assays demonstrated that IEC-6 cell proliferation is increased by a mixture containing thymidine but decreased by one containing uridine. In fact, the anti...

International journal of molecular sciences, 2011

Nanotechnology, along with related concepts such as nanomaterials, nanostructures and nanoparticl... more Nanotechnology, along with related concepts such as nanomaterials, nanostructures and nanoparticles, has become a priority area for scientific research and technological development. Nanotechnology, i.e., the creation and utilization of materials and devices at nanometer scale, already has multiple applications in electronics and other fields. However, the greatest expectations are for its application in biotechnology and health, with the direct impact these could have on the quality of health in future societies. The emerging discipline of nanomedicine brings nanotechnology and medicine together in order to develop novel therapies and improve existing treatments. In nanomedicine, atoms and molecules are manipulated to produce nanostructures of the same size as biomolecules for interaction with human cells. This procedure offers a range of new solutions for diagnoses and "smart" treatments by stimulating the body's own repair mechanisms. It will enhance the early diagn...

International Journal of Molecular Sciences, 2011

Breast cancer research has developed rapidly in the past few decades, leading to longer survival ... more Breast cancer research has developed rapidly in the past few decades, leading to longer survival times for patients and opening up the possibility of developing curative treatments for advanced breast cancer. Our increasing knowledge of the biological pathways associated with the progression and development of breast cancer, alongside the failure of conventional treatments, has prompted us to explore gene therapy as an alternative therapeutic strategy. We previously reported that gef gene from E. coli has shown considerable cytotoxic effects in breast cancer cells. However, its action mechanism has not been elucidated. Indirect immunofluorescence technique using flow cytometry and immunocytochemical analysis were used to detect breast cancer markers: estrogen (ER) and progesterone (PR) hormonal receptors, human epidermal growth factor receptor-2 proto-oncogene (c-erbB-2), ki-67 antigen and p53 protein. gef gene induces an increase in ER and PR expressions and a decrease in ki-67 and c-erbB-2 gene expressions, indicating a better prognosis and response to treatment and a longer disease-free interval and survival. It

Revista Española de Cardiología (English Edition), 2011

Stem Cell Research, 2013

Human adipose derived stem cells (hASCs) can be easily isolated and their plasticity has been wel... more Human adipose derived stem cells (hASCs) can be easily isolated and their plasticity has been well characterized. Several TGF-β superfamily ligands can direct hASCs towards chondrocytes. However, these ligands are difficult to purify and expensive. We have developed a library of Activin/BMP2 chimeric ligands (AB2 ligands) by systematically mixing their sequence segments and have tested their chondrogenic potential in hASCs. Cells cultured in monolayer or in a pellet culture system were incubated with a chemically defined medium supplemented with the chimeric ligands for 4 or 6 weeks and showed higher expression levels of type II collagen, aggrecan, and Sox9 mRNAs when compared with control and non-treated cells. Moreover, toluidine blue, alcian blue, and Masson's trichrome staining was markedly increased in treated cells, both in cell pellet and monolayer assays. In addition, immunohistochemical staining for detection of type I collagen, type II collagen, and Sox 9 demonstrated the acquisition of a chondrogenic phenotype in both culture systems. We present here an inexpensive and robust protocol for differentiation of hASCs towards chondrocytes in a reproducible and highly efficient manner. The AB2 ligands employed are easily produced and have properties that may become useful in cell therapy.

European Journal of …, 2012

PLoS ONE, 2011

The chemotherapeutic drug 5-FU is widely used in the treatment of a range of cancers, but resista... more The chemotherapeutic drug 5-FU is widely used in the treatment of a range of cancers, but resistance to the drug remains a major clinical problem. Since defects in the mediators of apoptosis may account for chemo-resistance, the identification of new targets involved in 5-FU-induced apoptosis is of main clinical interest. We have identified the ds-RNA-dependent protein kinase (PKR) as a key molecular target of 5-FU involved in apoptosis induction in human colon and breast cancer cell lines. PKR distribution and activation, apoptosis induction and cytotoxic effects were analyzed during 5-FU and 5-FU/IFNa treatment in several colon and breast cancer cell lines with different p53 status. PKR protein was activated by 5-FU treatment in a p53-independent manner, inducing phosphorylation of the protein synthesis translation initiation factor eIF-2a and cell death by apoptosis. Furthermore, PKR interference promoted a decreased response to 5-FU treatment and those cells were not affected by the synergistic antitumor activity of 5-FU/IFNa combination. These results, taken together, provide evidence that PKR is a key molecular target of 5-FU with potential relevance in the clinical use of this drug.

European Journal of …, 2012

Development of the European Higher Education Area is linked to the adoption of a new educational ... more Development of the European Higher Education Area is linked to the adoption of a new educational model. Thus, in the Health Sciences, basic science knowledge must be integrated with the clinical skills that students will require in their professional activity. The Anatomy and Embryology Teaching Investigation Group at our university (UGR-N-40-UCUA) designed a specific questionnaire to analyse specific items that affect Anatomy learning. It also developed a teaching methodology for the acquisition of anatomic knowledge, integrating theory and practice, including individual and collective tasks for students and leading to future self-learning. Analyses were performed in different groups of first-year students at the

Journal of Translational Medicine, 2012

Background The CD133 antigen is a marker of radio- and chemo-resistant stem cell populations in g... more Background The CD133 antigen is a marker of radio- and chemo-resistant stem cell populations in glioblastoma (GBM). The O6-methylguanine DNA methyltransferase (MGMT) enzyme is related with temozolomide (TMZ) resistance. Our propose is to analyze the prognostic significance of the CD133 antigen and promoter methylation and protein expression of MGMT in a homogenous group of GBM patients uniformly treated with radiotherapy and TMZ. The possible connection between these GBM markers was also investigated. Methods Seventy-eight patients with GBM treated with radiotherapy combined with concomitant and adjuvant TMZ were analyzed for MGMT and CD133. MGMT gene promoter methylation was determined by methylation-specific polymerase chain reaction after bisulfite treatment. MGMT and CD133 expression was assessed immunohistochemically using an automatic quantification system. Overall and progression-free survival was calculated according to the Kaplan–Meier method. Results The MGMT gene promoter...

International Journal of Cancer, 1998

Classical cytotoxic treatment of rhabdomyosarcoma (RMS) is accompanied often by significant morbi... more Classical cytotoxic treatment of rhabdomyosarcoma (RMS) is accompanied often by significant morbidity and poor response. The use of cytotoxic agents may induce a multidrug resistance phenotype, which plays an important role in the sensitivity of tumoral cells to drugs. Using actinomycin D, a drug of choice in the treatment of RMS, we induced resistance in the TE.32.7 human RMS cell line. The TE.32.7-DACresistant cell line exhibited cross-resistance to vincristine and doxorubicin and showed mdr1/P-glycoprotein over-expression, suggesting that this mechanism was involved in the reduction in intracellular drug concentration and may be responsible for the failure of treatment of RMS with classical cycles of cytotoxics. Furthermore, this resistant cell line showed increased expression of the muscle differentiation markers desmin and ␣-actinin and ultrastructural changes which clearly indicated myogenic differentiation. Our findings suggest that, although this tumor is probably arrested along the normal myogenic pathway to maturation, induction of cell differentiation with anti-neoplastic drugs may be an alternative therapeutic approach. However, the failure of TE.32.7-DAC cells to completely re-enter the program of myogenic differentiation supports the hypothesis that multidrug resistance is a major obstacle in differentiation therapy for RMS.

Experimental Dermatology, 2010

Novel treatment modalities, including gene therapy, are needed for patients with advanced melanom... more Novel treatment modalities, including gene therapy, are needed for patients with advanced melanoma. We evaluated whether the gef gene, a suicide gene from Escherichia coli, had a significant cytotoxic impact on melanoma in vivo. First, we used a non-viral gene delivery approach (pcDNA3.1/ge/) to study the inhibition of melanoma cells (B16-F10) proliferation in vitro. Secondly, we used direct intra-tumoral injection of pcDNA3.1/ge/ complexed with jetPEI to deliver gef cDNA to rapidly growing murine melanomas. We demonstrated that gef gene not only has an antiproliferative effect on B16-F10 cells in vitro, but also