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Pilar Roca

11101 Background: The liquid biopsy is a noninvasive tool that could change the vision of diagnostic, prognostic and predictive analysis in oncology. In the liquid biopsy potential blood-based biomarkers such as exosomes could be... more
11101 Background: The liquid biopsy is a noninvasive tool that could change the vision of diagnostic, prognostic and predictive analysis in oncology. In the liquid biopsy potential blood-based biomarkers such as exosomes could be determinate. These biological nanovescicles (40-100 nm) are involved in regulation of tumor progression and it was demonstrated that they transport miRNAs. miRNAs are shown to be key regulators of many biological processes and promising disease biomarkers. The main aim of this study is to investigate whether exosomes isolation from clinical samples (fresh plasma from NSCLC pts) is feasible. Furthermore we have investigated selected exosome miRNAs known to be related with NSCLC. Methods: A total of 12 patients with NSCLC (adenocarcinoma) were included in this pilot project, after obtaining the informed consent. Exosomes were isolated from fresh plasma by means of both Density-Gradient centrifugation and commercial isolation kit and characterized through Western-Blot (WB), NanoSigh...
Supplemental Figure 1. SIRT3 levels after SIRT3-shRNA transfection and clonal selection. A: SIRT3 mRNA and protein levels after SIRT3 silencing. B: Representative bands of SIRT3 Western Blot and tubulin as a loading control. Values are... more
Supplemental Figure 1. SIRT3 levels after SIRT3-shRNA transfection and clonal selection. A: SIRT3 mRNA and protein levels after SIRT3 silencing. B: Representative bands of SIRT3 Western Blot and tubulin as a loading control. Values are expressed as mean ± SEM (n=6) and normalized to control value. Student's t-test: * indicates a significant difference between control and SIRT3-silenced cells (P<0.05).
Introduccion: El receptor de melanocortina 1 (MC1R) es un gen clave para el desarrollo del melanoma, ya que esta implicado en la pigmentacion de la piel y la proteccion contra la radiacion ultravioleta. Ademas, estudios recientes sugieren... more
Introduccion: El receptor de melanocortina 1 (MC1R) es un gen clave para el desarrollo del melanoma, ya que esta implicado en la pigmentacion de la piel y la proteccion contra la radiacion ultravioleta. Ademas, estudios recientes sugieren que tambien podria tener un papel importante en la regulacion de las especies reactivas de oxigeno (ROS). Objetivo: Nuestro objetivo fue analizar si la estimulacion de MC1R afecta a los principales genes implicados en la biogenesis mitocondrial y la respuesta antioxidante. Material y Metodos: Se estudiaron las lineas celulares de melanoma HBL, con el MC1R salvaje, y A375, con el receptor mutado, y fueron tratadas con un analogo de la hormona estimuladora de melanocitos, la NDP-MSH. Resultados: Los resultados obtenidos muestran que, en condiciones basales, los niveles de expresion de genes que controlan la biogenesis mitocondrial y la respuesta antioxidante son significativamente mayores en la linea HBL, que presenta el receptor funcional. Ademas, e...
Background/Aims: Large-scale epidemiological studies support a correlation between obesity and breast cancer in postmenopausal women. Circulating leptin levels are increased in obese and it has been suggested to play a significant role in... more
Background/Aims: Large-scale epidemiological studies support a correlation between obesity and breast cancer in postmenopausal women. Circulating leptin levels are increased in obese and it has been suggested to play a significant role in mammary tumor formation and progression. Moreover, regulation of oxidative stress is another important factor in both tumor development and responses to anticancer therapies. The aim of this study was to examine the relationship between oxidative stress and chronic leptin exposure. Methods: We treated MCF-7 breast cancer cells with 100 ng/mL leptin for 10 days and analyzed cell growth, ROS production and oxidative damage, as well as, some of the main antioxidant systems. Furthermore, since the hyperleptinemia has been associated with a worse pathology prognosis, we decided to test the influence of leptin in response to cisplatin anticancer treatment. Results: Leptin signalling increased cell proliferation but reduced ROS production, as well as, oxi...
Simple Summary Colorectal cancer (CRC) is one of the most frequent cancers worldwide. Early detection of CRC is crucial, as it greatly improves the survival of patients. Currently, the CRC screening programs consist of a stool test to... more
Simple Summary Colorectal cancer (CRC) is one of the most frequent cancers worldwide. Early detection of CRC is crucial, as it greatly improves the survival of patients. Currently, the CRC screening programs consist of a stool test to detect the presence of blood in stool and a subsequent colonoscopy to confirm the diagnosis. However, CRC screening can be further improved with the use of new biomarkers. Omics technologies, that is, techniques that generate a vast amount of data, can help to establish these markers. Here, we discuss the use of omics with different types of samples (breath, urine, stool, blood, bowel lavage fluid, and tissue) and highlight some of the most relevant biomarkers that have been recently detected. Abstract Colorectal cancer (CRC) is one of the most frequently diagnosed cancers with high mortality rates, especially when detected at later stages. Early detection of CRC can substantially raise the 5-year survival rate of patients, and different efforts are be...
Genistein could play a crucial role in modulating three closely linked physiological processes altered during cancer: oxidative stress, mitochondrial biogenesis, and inflammation. However, genistein’s role in colorectal cancer remains... more
Genistein could play a crucial role in modulating three closely linked physiological processes altered during cancer: oxidative stress, mitochondrial biogenesis, and inflammation. However, genistein’s role in colorectal cancer remains unclear. We aimed to determine genistein’s effects in two colon cancer cells: HT29 and SW620, primary and metastatic cancer cells, respectively. After genistein treatment for 48 h, cell viability and hydrogen peroxide (H2O2) production were studied. The cell cycle was studied by flow cytometry, mRNA and protein levels were analyzed by RT-qPCR and Western blot, respectively, and finally, cytoskeleton remodeling and NF-κB translocation were determined by confocal microscopy. Genistein 100 µM decreased cell viability and produced G2/M arrest, increased H2O2, and produced filopodia in SW620 cells. In HT29 cells, genistein produced an increase of cell death, H2O2 production, and in the number of stress fibers. In HT29 cells, mitochondrial biogenesis was inc...
Most colorectal cancer (CRC) patients die as a consequence of metastasis. Mitochondrial dysfunction could enhance cancer development and metastatic progression. We aimed to evaluate the adaptations associated with mitochondrial function... more
Most colorectal cancer (CRC) patients die as a consequence of metastasis. Mitochondrial dysfunction could enhance cancer development and metastatic progression. We aimed to evaluate the adaptations associated with mitochondrial function in tumor tissues from stages III and IV of human CRC and whether they could ultimately be used as a therapeutic target in metastatic colorectal cancer (mCRC). We analyzed the protein levels by Western blotting and the enzymatic activities of proteins involved in mitochondrial function, as well as the amount of mitochondrial DNA (mtDNA), by real-time PCR, analyzing samples of non-tumor adjacent tissue and tumor tissue from stages III and IV CRC patients without radio- or chemotherapy treatment prior to surgery. Our data indicate that the tumor tissue of pre-metastatic stage III CRC exhibited an oxidant metabolic profile very similar to the samples of non-tumor adjacent tissue of both stages. Notable differences in the protein expression levels of ATPa...
Obesity, a physiological situation where different proinflammatory cytokines and hormones are secreted, is a major risk factor for breast cancer. Mitochondrial functionality exhibits a relevant role in the tumorigenic potential of a... more
Obesity, a physiological situation where different proinflammatory cytokines and hormones are secreted, is a major risk factor for breast cancer. Mitochondrial functionality exhibits a relevant role in the tumorigenic potential of a cancer cell. In the present study, it has been examined the influence of an obesity-related inflammation ELIT treatment (17β-estradiol, leptin, IL-6, and TNFα), which aims to stimulate the hormonal conditions of a postmenopausal obese woman on the mitochondrial functionality and invasiveness of MCF7 and T47D breast cancer cell lines, which display a different ratio of both estrogen receptor isoforms, ERα and ERβ. The results showed a decrease in mitochondrial functionality, with an increase in oxidative stress and invasiveness and motility, in the MCF7 cell line (high ERα/ERβ ratio) compared to a maintained status in the T47D cell line (low ERα/ERβ ratio) after ELIT treatment. In addition, breast cancer biopsies were analyzed, showing that breast tumors ...
Phytoestrogens are a large group of natural compounds found in more than 300 plants. They have a close structural similarity to estrogens, which allow them to bind to both estrogen receptors (ER), ERα and ERβ, presenting a weak estrogenic... more
Phytoestrogens are a large group of natural compounds found in more than 300 plants. They have a close structural similarity to estrogens, which allow them to bind to both estrogen receptors (ER), ERα and ERβ, presenting a weak estrogenic activity. Phytoestrogens have been described as antioxidant, anti-inflammatory, anti-thrombotic, anti-allergic, and anti-tumoral agents. Their role in cancer prevention has been well documented, although their impact on treatment efficiency is controversial. Several reports suggest that phytoestrogens may interfere with the effect of anti-cancer drugs through the regulation of oxidative stress and other mechanisms. Furthermore, some phytoestrogens could exert a protective effect on healthy cells, thus reducing the secondary effects of cancer treatment. In this review, we have studied the recent research in this area to find evidence for the role of phytoestrogens in cancer prevention and therapy efficacy.
Selenium is a micronutrient which is found in many foods, with redox status modulation activity. Our aim was to evaluate the effects of two chemical forms of selenoamino acids, Seleno-L-methionine and Seleno-L-cystine (a diselenide... more
Selenium is a micronutrient which is found in many foods, with redox status modulation activity. Our aim was to evaluate the effects of two chemical forms of selenoamino acids, Seleno-L-methionine and Seleno-L-cystine (a diselenide derived from selenocysteine), at different concentrations on cell viability, hydrogen peroxide production, antioxidant enzymes, UCP2 protein expression, as well as lipid and protein oxidative damage in MCF-7 breast cancer cells. Results showed that Seleno-L-methionine did not cause an increase in hydrogen peroxide production at relatively low concentrations, accompanied by a rise in the antioxidant enzymes catalase and MnSOD, and UCP2 protein expression levels. Furthermore, a decrease in protein and lipid oxidative damage was observed at 10 µM concentration. Otherwise, Seleno-L-cystine increased hydrogen peroxide production from relatively low concentrations (100 nM) to a large increase at high concentrations. Moreover, at 10 µM, Seleno-L-cystine decrease...
Abstract Xanthohumol (XN) is a hop-derived prenylflavonoid and have been reported to exhibit anticancer properties in several types of cancer. It presents a great interest against colon cancer due to high exposure of this compound in this... more
Abstract Xanthohumol (XN) is a hop-derived prenylflavonoid and have been reported to exhibit anticancer properties in several types of cancer. It presents a great interest against colon cancer due to high exposure of this compound in this tissue. Metastatic SW620 cell line was treated with doses ranging from 0.001 to 10 µM of XN to assess their effects on cell viability and mitochondrial function. At low concentrations, XN had no effect on assays carried out, but high concentration of XN led to a decrease in cell viability. In addition, at 10 μM XN, it gave rise to an increase in ROS production accompanied by a decrease in OXPHOS complexes and sirtuin 1 protein expression levels. These results suggest that XN could act as a mitocan and impairs mitochondrial function.
Sirtuin 3 (SIRT3) is the major deacetylase in mitochondria and is activated under oxidative stress conditions. SIRT3 regulates mitochondrial metabolism and the antioxidant response to lower reactive oxygen species (ROS) production. Thus,... more
Sirtuin 3 (SIRT3) is the major deacetylase in mitochondria and is activated under oxidative stress conditions. SIRT3 regulates mitochondrial metabolism and the antioxidant response to lower reactive oxygen species (ROS) production. Thus, SIRT3 could allow cells to counteract the effect of anticancer therapies, which increase ROS levels. The aim of this study was to determine whether SIRT3 knockdown in colon cancer cells could increase oxidative stress and therefore make them more sensitive to cytotoxic treatments. A stable SIRT3 silencing in SW620 human cell line was achieved through a specific shRNA. Expression of antioxidant enzymes and mitochondrial proteins was analyzed, as well as protein levels by Western Blot and MnSOD enzymatic activity. Cells were also treated with oxaliplatin to study ROS production by Amplex Red®. SIRT3 silencing resulted in a decrease of both antioxidant enzymes and proteins related to mitochondrial function, as well as a reduction in MnSOD activity. Furthermore, SIRT3 knockdown produced a significant increase in ROS production, which was greater with oxaliplatin treatment. Overall, these results suggest that SIRT3 is a key factor regulating mitochondria under oxidative stress. SIRT3 knockdown could be a therapeutic strategy for colon cancer, since it improves the effectiveness of cytotoxic treatments.
The polyphenol resveratrol (RSV) is found in the skin of red grapes and has been reported to exhibit anticancer properties. The antitumor effects of RSV in the gastrointestinal tract have gained considerable interest due to the high... more
The polyphenol resveratrol (RSV) is found in the skin of red grapes and has been reported to exhibit anticancer properties. The antitumor effects of RSV in the gastrointestinal tract have gained considerable interest due to the high exposure of this tissue to this dietary compound. One of the hallmarks of cancer cells is their particular metabolism mainly relying on glycolysis for ATP production rather than mitochondrial oxidative phosphorylation. Although RSV has been described to act as a calorie-restriction mimetic, modulating energy metabolism in normal tissues, little efforts have been done to study the effects of this polyphenol in the metabolism of cancer cells. Taking this into account, the aim of this study was to explore metabolic effects of this polyphenol in colon cancer. Oxygen consumption, ATP levels, Western blotting and other molecular biology techniques were carried out to characterize the metabolic signature of RSV in SW620 colon cancer cells. Paradoxically, the cy...
Several evidence indicate that metabolic alterations play a pivotal role in cancer development. Here, we report that the mitochondrial uncoupling protein 2 (UCP2) sustains the metabolic shift from mitochondrial oxidative phosphorylation... more
Several evidence indicate that metabolic alterations play a pivotal role in cancer development. Here, we report that the mitochondrial uncoupling protein 2 (UCP2) sustains the metabolic shift from mitochondrial oxidative phosphorylation (mtOXPHOS) to glycolysis in pancreas cancer cells. Indeed, we show that UCP2 sensitizes pancreas cancer cells to the treatment with the glycolytic inhibitor 2-deoxy-D-glucose. Through a bidimensional electrophoresis analysis, we identify 19 protein species differentially expressed after treatment with the UCP2 inhibitor genipin and, by bioinformatic analyses, we show that these proteins are mainly involved in metabolic processes. In particular, we demonstrate that the antioxidant UCP2 induces the expression of hnRNPA2/B1, which is involved in the regulation of both GLUT1 and PKM2 mRNAs, and of lactate dehydrogenase (LDH) increasing the secretion of L-lactic acid. We further demonstrate that the radical scavenger N-acetyl-L-cysteine reverts hnRNPA2/B1 and PKM2 inhibition by genipin indicating a role for reactive oxygen species in the metabolic reprogramming of cancer cells mediated by UCP2. We also observe an UCP2-dependent decrease in mtOXPHOS complex I (NADH dehydrogenase), complex IV (cytochrome c oxidase), complex V (ATPase) and in mitochondrial oxygen consumption, suggesting a role for UCP2 in the counteraction of pancreatic cancer cellular respiration. All these results reveal novel mechanisms through which UCP2 promotes cancer cell proliferation with the concomitant metabolic shift from mtOXPHOS to the glycolytic pathway.
The effects of starvation on the thermogenic parameters of three different mitochondrial subpopulations in brown adipose tissue (BAT) of both post-cafeteria obese and lean rats were investigated. Tissue from different BAT depots from fed... more
The effects of starvation on the thermogenic parameters of three different mitochondrial subpopulations in brown adipose tissue (BAT) of both post-cafeteria obese and lean rats were investigated. Tissue from different BAT depots from fed and 24 h starved rats were collected, pooled and three mitochondrial subpopulations were isolated by differential centrifugation; the M1 fraction (1000 g), the M3 fraction (3000 g) and the M15 fraction (15000 g). Thermogenic parameters were measured in the three mitochondrial subtypes, and uncoupling protein (UCP) mRNA was determined in BAT. The results showed that starvation induced a decrease in mitochondrial turnover in BAT from both lean and obese rats. Moreover, a selective net loss of UCP from the lightest mitochondrial fraction (M15) in lean rats, with a concomitant reduction of UCP mRNA was observed. The reductions did not occur in obese rats and, as a result, a change in UCP distribution between the mitochondrial subpopulations was produced...
Breast cancer is a leading cause of death for women. The estrogen receptors (ERs) ratio is important in the maintenance of mitochondrial redox status, and higher levels of ERβ increases mitochondrial functionality, decreasing ROS... more
Breast cancer is a leading cause of death for women. The estrogen receptors (ERs) ratio is important in the maintenance of mitochondrial redox status, and higher levels of ERβ increases mitochondrial functionality, decreasing ROS production. Our aim was to determine the interaction between the ERα/ERβ ratio and the response to cytotoxic treatments such as cisplatin (CDDP), paclitaxel (PTX) and tamoxifen (TAM). Cell viability, apoptosis, autophagy, ROS production, mitochondrial membrane potential, mitochondrial mass and mitochondrial functionality were analyzed in MCF-7 (high ERα/ERβ ratio) and T47D (low ERα/ERβ ratio) breast cancer cell lines. Cell viability decreased more in MCF-7 when treated with CDDP and PTX. Apoptosis was less activated after cytotoxic treatments in T47D than in MCF-7 cells. Nevertheless, autophagy was increased more in CDDP-treated MCF-7, but less in TAM-treated cells than in T47D. CDDP treatment produced a raise in mitochondrial mass in MCF-7, as well as the citochrome c oxidase (COX) and ATP synthase protein levels, however significantly reduced COX activity. In CDDP-treated cells, the overexpression of ERβ in MCF-7 caused a reduction in apoptosis, autophagy and ROS production, leading to higher cell survival; and the silencing of ERβ in T47D cells promoted the opposite effects. In TAM-treated cells, ERβ-overexpression led to less cell viability by an increment in autophagy; and the partial knockdown of ERβ in T47D triggered an increase in ROS production and apoptosis, leading to cell death. In conclusion, ERβ expression plays an important role in the response of cancer cells to cytotoxic agents, especially for cisplatin treatment.
In calcium urolithiasis, inhibitors have a significant role to play in reducing the crystallization processes (1). Some urinary inhibitors which include magnesium, pyrophosphate, citrate, and glycosaminoglycans have been determined in a... more
In calcium urolithiasis, inhibitors have a significant role to play in reducing the crystallization processes (1). Some urinary inhibitors which include magnesium, pyrophosphate, citrate, and glycosaminoglycans have been determined in a group of patients with calcium-oxalate (CaOx) urolithiasis and in a control group of healthy subjects in order to detect any possible differences between the two groups of individuals.
The recently published existence of a pool of amino acids absorbed onto the blood cell membranes in the rat has provided a new insight into the role of the blood cell amino acid pools, in the context of tissue-blood amino acid transport... more
The recently published existence of a pool of amino acids absorbed onto the blood cell membranes in the rat has provided a new insight into the role of the blood cell amino acid pools, in the context of tissue-blood amino acid transport and their metabolic relationships. In the present study, this pool has been measured in a large (n = 40) representative healthy human population. This pool represents 9% of the blood cell amino acids, which is somewhat lower but in the same order as that previously measured in the rat. The inside-erythrocyte and plasma pools have also been quantified, giving an inside to outside ratio of 1.32 for the combined total amino acids. Statistically significant age related changes in the different blood compartments were detected for some amino acids (aspartate, asparagine, glutamine, tyrosine, methionine, phenylalanine, tryptophan and lysine) as well as for the ratio of tryptophan to the large neutral amino acids. The results obtained emphasize the importan...
The "in vivo" handling of L-alanine in 24 hours starved rats, in which obesity was induced by feeding with cafeteria diet, was compared with that of starved control rats. 14C-alanine was administered in trace amounts in order... more
The "in vivo" handling of L-alanine in 24 hours starved rats, in which obesity was induced by feeding with cafeteria diet, was compared with that of starved control rats. 14C-alanine was administered in trace amounts in order not to affect the normal handling of this amino acid. The results obtained in blood and liver support a lowered glucose formation from alanine. The specific radioactivities corresponding to lactate, glutamate + glutamine and asparagine as well as total protein and total lipid, were all lowered in the obese group. This strongly suggests that glucose formation from alanine in the liver was impaired. The specific radioactivity of the metabolites studied in the striated muscle are compatible with the above suggestion. It can be concluded that the glucose alanine cycle operation is inhibited in the cafeteria diet starved obese rats.
Alanine metabolism in 24 hour starved 20-day pregnant rats, following intravenously administered C14-alanine, in trace dose that does not affect the normal availability of this amino acid, has been studied. The steady state levels of... more
Alanine metabolism in 24 hour starved 20-day pregnant rats, following intravenously administered C14-alanine, in trace dose that does not affect the normal availability of this amino acid, has been studied. The steady state levels of alanine and glucose in blood, liver and skeletal muscle, together with the tissue glycogen, metabolites and amino acid composition pools, are given in both the maternal and foetal compartments compared with the virgin control rats. The utilization of alanine as a gluconeogenetic precursor is not increased in late pregnancy under 24-hour starvation and it depends on the lower blood substrate availability.
Ovarian carcinoma is the main cause of gynecological cancer related deaths. The aim of this study was to determine the activation status of the antioxidant response in samples of ovarian serous carcinoma from paraffin-embedded biopsies... more
Ovarian carcinoma is the main cause of gynecological cancer related deaths. The aim of this study was to determine the activation status of the antioxidant response in samples of ovarian serous carcinoma from paraffin-embedded biopsies and compare them with the response of patients to carboplatin-paclitaxel treatment. Estrogen receptor alpha (ERα), antioxidant enzymes, and uncoupling protein (UCP) levels were analyzed by western blotting and the presence of estrogen receptor beta (ERβ) was investigated by immunohistochemistry (IHC). Lower levels of ERα, antioxidant enzymes and UCPs were found in patients resistant to treatment in comparison to the carboplatin/paclitaxel-sensitive ones; IHC revealed a greater presence of ERβ in sensitive patients. These results indicate that patients resistant to treatment have a lower level of antioxidant response activation compared to sensitive patients, fact which may be related to the efficacy of this treatment.

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