26 research outputs found
Corrigendum : Pío del Río-Hortega: A Visionary in the Pathology of Central Nervous System Tumors
Fondo de Investigaciones Sanitarias (11/00185), Redes Temáticas de Investigación Cooperativa en Salud (Ref. RD06/0020/1020
The visual neural networks of Ramón y Cajal: comments on the facsimile of one of his handwritten drawings exhibited at the museum of the history of medicine of the National Academy of Medicine of Colombia
La obra de Santiago Ramón y Cajal ha sido ampliamente comentada en biografías y artículos científicos. El presente texto busca aportar información historiográfica sobre una ilustración facsimilar donada a la Academia Nacional de Medicina de Colombia, que se encuentra expuesta en su Museo de la Historia de la Medicina en Bogotá. Para el efecto, se recurrió a los archivos del Instituto Cajal en Madrid, España, en donde se conserva su legado original.The work of Santiago Ramón y Cajal has been widely commented in biographies and scientific articles. This text seeks to provide historiographical information on a facsimile illustration do-nated to the National Academy of Medicine of Colombia, currently on display in its permanent collections at the Museum of the History of Medicine in Bogotá. For this purpose, we accessed the archives of the Cajal Institute in Madrid, Spain, where his original legacy is preserved.https://orcid.org/0000-0002-5592-3844https://orcid.org/0000-0002-7147-425XRevista Nacional - IndexadaN
Increased voltage-dependent K+ channel Kv1.3 and Kv1.5 expression correlates with leiomyosarcoma aggressiveness
Voltage-dependent K+ channels (Kv) are involved in the proliferation and differentiation of mammalian cells, since Kv antagonists impair cell cycle progression. Although myofibers are terminally differentiated, some myoblasts may re-enter the cell cycle and proliferate. Since Kv1.3 and Kv1.5 expression is remodeled during tumorigenesis and is involved in smooth muscle proliferation, the purpose of this study was to analyze the expression of Kv1.3 and Kv1.5 in smooth muscle neoplasms. In the present study, we examined human samples of smooth muscle tumors together with healthy specimens. Thus, leiomyoma (LM) and leiomyosarcoma (LMS) tumors were analyzed. Results showed that Kv1.3 was poorly expressed in the healthy muscle and indolent LM specimens, whereas aggressive LMS showed high levels of Kv1.3 expression. Kv1.5 staining was correlated with malignancy. The findings show a remodeling of Kv1.3 and Kv1.5 in human smooth muscle sarcoma. A correlation of Kv1.3 and Kv1.5 expression with tumor aggressiveness was observed. Thus, our results indicate Kv1.5 and Kv1.3 as potential tumorigenic targets for aggressive human LMS
Guidelines for biomarker testing in advanced colorectal carcinoma. A National Consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology
Este documento de consenso nace como una iniciativa conjunta de la Sociedad Española de Anatomía Patológica (SEAP) y de la Sociedad Española de Oncología Médica (SEOM) y propone recomendaciones diagnósticas y terapéuticas para el manejo del paciente con cáncer colorrectal (CCR) hereditario, localizado y avanzado basadas en la evidencia científica que existe en la actualidad sobre el uso de biomarcadores. Por tanto, este documento supone una oportunidad para mejorar la eficiencia de la actividad asistencial y la utilización de recursos, lo que redundará en un beneficio para estos pacientes. Con los datos disponibles en la actualidad, este grupo de expertos recomienda que en los pacientes con CCR localizado se determine la inestabilidad de microsatélites, ya que es un factor predictivo relevante para decidir el tratamiento adyuvante. Sin embargo, aunque las firmas de expresión genética ColoPrint® y Oncotype Dx® han demostrado tener valor pronóstico, no existe todavía consenso sobre su uso en la práctica clínica. En cuanto al CCR avanzado, la determinación del estado mutacional de KRAS es indispensable antes de administrar un tratamiento con anti-receptor del factor de crecimiento epidérmico (EGFR), como cetuximab y panitumumab. Sin embargo, la determinación de otros biomarcadores, como las mutaciones de BRAF, EGFR, PI3K y PTEN, no debe llevarse a cabo de forma rutinaria, ya que hoy por hoy no influye en la planificación del tratamiento. Otros aspectos importantes que incluye son los requisitos organizativos y los controles de calidad que deben existir para la adecuada determinación de estos biomarcadores, así como las implicaciones legales que se deben tener en cuenta
Phenformin-Induced Mitochondrial Dysfunction Sensitizes Hepatocellular Carcinoma for Dual Inhibition of mTOR
Purpose: Hepatocellular carcinoma (HCC) ranks second in cancer mortality and has limited therapeutic options. We recently described the synergistic effect of allosteric and ATP-site competitive inhibitors against the mTOR for the treatment of HCC. However, such inhibitors induce hyperglycemia and increase mitochondrial efficiency. Here we determined whether the mitochondrial complex I inhibitor phenformin could reverse both side effects, impose an energetic stress on cancer cells, and suppress the growth of HCC.
Experimental Design: Human HCC cell lines were used in vitro to access the signaling and energetic impact of mTOR inhibitors and phenformin, either alone or in combination. Next, the therapeutic utility of these drugs alone or in combination was investigated preclinically in human orthotopic tumors implanted in mice, by analyzing their impact on the tumor burden and overall survival.
Results: We found phenformin caused mitochondrial dysfunction and fragmentation, inducing a compensatory shift to glycolysis. In contrast, dual inhibition of mTOR impaired cell growth and glycolysis, while increasing mitochondrial fusion and efficiency. In a mouse model of human HCC, dual inhibition of mTOR, together with phenformin, was highly efficacious in controlling tumor burden. However, more strikingly, pretreatment with phenformin sensitized tumors to dual inhibition of mTOR, leading to a dramatic improvement in survival.
Conclusions: Treatment of HCC cells in vitro with the biguanide phenformin causes a metabolic shift to glycolysis, mitochondrial dysfunction and fragmentation, and dramatically sensitizes orthotopic liver tumors to dual inhibition of mTOR. We therefore propose this therapeutic approach should be tested clinically in HCC
miR-125b Acts as a Tumor Suppressor in Breast Tumorigenesis via Its Novel Direct Targets ENPEP, CK2-α, CCNJ, and MEGF9
MicroRNAs (miRNAs) play important roles in diverse biological processes and are emerging as key regulators of tumorigenesis and tumor progression. To explore the dysregulation of miRNAs in breast cancer, a genome-wide expression profiling of 939 miRNAs was performed in 50 breast cancer patients. A total of 35 miRNAs were aberrantly expressed between breast cancer tissue and adjacent normal breast tissue and several novel miRNAs were identified as potential oncogenes or tumor suppressor miRNAs in breast tumorigenesis. miR-125b exhibited the largest decrease in expression. Enforced miR-125b expression in mammary cells decreased cell proliferation by inducing G2/M cell cycle arrest and reduced anchorage-independent cell growth of cells of mammary origin. miR-125b was found to perform its tumor suppressor function via the direct targeting of the 3'-UTRs of ENPEP, CK2-alpha, CCNJ, and MEGF9 mRNAs. Silencing these miR-125b targets mimicked the biological effects of miR-125b overexpression, confirming that they are modulated by miR-125b. Analysis of ENPEP, CK2-alpha, CCNJ, and MEGF9 protein expression in breast cancer patients revealed that they were overexpressed in 56%, 40-56%, 20%, and 32% of the tumors, respectively. The expression of ENPEP and CK2-alpha was inversely correlated with miR-125b expression in breast tumors, indicating the relevance of these potential oncogenic proteins in breast cancer patients. Our results support a prognostic role for CK2-alpha, whose expression may help clinicians predict breast tumor aggressiveness. In particular, our results show that restoration of miR-125b expression or knockdown of ENPEP, CK2-alpha, CCNJ, or MEGF9 may provide novel approaches for the treatment of breast cancer
Genomic Analyses across Six Cancer Types Identify Basal-like Breast Cancer as a Unique Molecular Entity
To improve our understanding of the biological relationships among different types of cancer, we have characterized variation in gene expression patterns in a set of 1,707 samples representing 6 human cancer types (breast, ovarian, brain, colorectal, lung adenocarcinoma and squamous cell lung cancer). In the unified dataset, breast tumors of the Basal-like subtype were found to represent a unique molecular entity as any other cancer type, including the rest of breast tumors, while showing striking similarities with squamous cell lung cancers. Moreover, gene signatures tracking various cancer- and stromal-related biological processes such as proliferation, hypoxia and immune activation were found expressed similarly in different proportions of tumors across the various cancer types. These data suggest that clinical trials focusing on tumors with common profiles and/or biomarker expression rather than their tissue of origin are warranted with a special focus on Basal-like breast cancer and squamous cell lung carcinoma
Prostate tumor OVerexpressed-1 (PTOV1) down-regulates HES1 and HEY1 notch targets genes and promotes prostate cancer progression
Background PTOV1 is an adaptor protein with functions in diverse processes, including gene transcription and protein translation, whose overexpression is associated with a higher proliferation index and tumor grade in prostate cancer (PC) and other neoplasms. Here we report its interaction with the Notch pathway and its involvement in PC progression. Methods Stable PTOV1 knockdown or overexpression were performed by lentiviral transduction. Protein interactions were analyzed by co-immunoprecipitation, pull-down and/or immunofluorescence. Endogenous gene expression was analyzed by real time RT-PCR and/or Western blotting. Exogenous promoter activities were studied by luciferase assays. Gene promoter interactions were analyzed by chromatin immunoprecipitation assays (ChIP). In vivo studies were performed in the Drosophila melanogaster wing, the SCID-Beige mouse model, and human prostate cancer tissues and metastasis. The Excel package was used for statistical analysis [...]
Five microRNAs in Serum Are Able to Differentiate Breast Cancer Patients From Healthy Individuals
Breast cancer is the cancer with the most incidence and mortality in women. microRNAs
are emerging as novel prognosis/diagnostic tools. Our aim was to identify a serum
microRNA signature useful to predict cancer development. We focused on studying
the expression levels of 30 microRNAs in the serum of 96 breast cancer patients vs.
92 control individuals. Bioinformatic studies provide a microRNA signature, designated
as a predictor, based on the expression levels of five microRNAs. Then, we tested the
predictor in a group of 60 randomly chosen women. Lastly, a proteomic study unveiled
the overexpression and downregulation of proteins differently expressed in the serum of
breast cancer patients vs. that of control individuals. Twenty-six microRNAs differentiate
cancer tissue from healthy tissue, and 16 microRNAs differentiate the serum of cancer
patients from that of the control group. The tissue expression of miR-99a, miR-497,
miR-362, and miR-1274, and the serum levels of miR-141 correlated with patient survival.
Moreover, the predictor consisting of miR-125b, miR-29c, miR-16, miR-1260, and
miR-451 was able to differentiate breast cancer patients from controls. The predictor was
validated in 20 new cases of breast cancer patients and tested in 60 volunteer women,
assigning 11 out of 60 women to the cancer group. An association of low levels of miR-16
with a high content of CD44 protein in serum was found. Circulating microRNAs in serum
can represent biomarkers for cancer prediction. Their clinical relevance and the potential
use of the predictor here described are discussed
The voltage-dependent K+ channels Kv1.3 and Kv1.5 in human cancer
Voltage-dependent K+ channels (Kv) are involved in a number of physiological processes, including immunomodulation, cell volume regulation, apoptosis as well as differentiation. Some Kv channels participate in the proliferation and migration of normal and tumor cells, contributing to metastasis. Altered expression of Kv1.3 and Kv1.5 channels has been found in several types of tumors and cancer cells. In general, while the expression of Kv1.3 apparently exhibits no clear pattern, Kv1.5 is induced in many of the analyzed metastatic tissues. Interestingly, evidence indicates that Kv1.5 channel shows inversed correlation with malignancy in some gliomas and non-Hodgkin's lymphomas. However, Kv1.3 and Kv1.5 are similarly remodeled in some cancers. For instance, expression of Kv1.3 and Kv1.5 correlates with a certain grade of tumorigenicity in muscle sarcomas. Differential remodeling of Kv1.3 and Kv1.5 expression in human cancers may indicate their role in tumor growth and their importance as potential tumor markers. However, despite of this increasing body of information, which considers Kv1.3 and Kv1.5 as emerging tumoral markers, further research must be performed to reach any conclusion. In this review, we summarize what it has been lately documented about Kv1.3 and Kv1.5 channels in human cancer