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Las masas anexiales son un hallazgo común en la práctica ginecológica, y a menudo se presentan dilemas tanto en el diagnóstico como en su manejo. El fin último del manejo de las mismas es el diagnóstico precoz del cáncer de ovario, el cual presenta una supervivencia baja en estadios avanzados y frente al cual todavía no existe métodos de screening. En la actualidad, el CA125 es el marcador tumoral recomendado tanto en la Oncoguía SEGO del Cáncer Epitelial de Ovario 2014 como en las guías NCCN 2015 para establecer un diagnóstico frente a una masa anexial sospechosa o como ayuda en la detección de carcinoma ovárico residual en pacientes que han recibido quimioterapia de primera línea. Sin embargo, no es recomendado como método de detección precoz en pacientes asintomáticas, dada su falta de sensibilidad para el diagnóstico de cánceres de ovario en estadio I, así como su falta de especificidad. Hipótesis principales 1. El marcador tumoral HE4, aplicado a las pacientes de nuestro medio, presenta una capacidad diagnóstica mayor al CA125 en el diagnóstico diferencial de las masas ováricas, principalmente en pacientes premenopáusicas. 2. El Índice ROMA tiene una mayor capacidad diagnóstica que los marcadores HE4 y CA125 considerados aisladamente para la valoración de las tumoraciones ováricas en pacientes posmenopáusicas. 3. El Índice ROMA y HE4 poseen una mejor capacidad diagnóstica que el Risk of Malignancy Index (RMI) en el diagnóstico diferencial de masas anexiales. Material y Método Estudio prospectivo, de tipo observacional, de una muestra de 96 pacientes intervenidas quirúrgicamente por masas o quistes anexiales sospechosos en el Hospital Materno Infantil de Málaga, Hospital Comarcal de Antequera y Hospital Comarcal de la Axarquía, a las cuales se les determinó los marcadores tumorales CA125, HE4, CA19.9, y los Índices de Riesgo ROMA y Risk of Malignancy Index (RMI), con objeto de valorar el nuevo marcador HE4 y el Índice ROMA frente al marcador existente (CA125). Para la realización del estudio se ha tomado como muestra aquellas pacientes derivadas a cirugía por masas o quistes anexiales desde Enero de 2014 hasta agosto de 2015, que cumplieran con unos criterios de inclusión y exclusión, por la necesidad de un resultado histopatológico que permitiera comparar el diagnóstico de sospecha con un diagnóstico definitivo y poder evaluar los marcadores CA125 y HE4, el Índice ROMA y el RMI. Resultados Un total de 96 pacientes fueron derivadas a cirugía por masas o quistes anexiales, siendo diagnosticadas 40 pacientes (41.7%) de una patología benigna, 40 pacientes (41.7%) de un tumor maligno de ovario, 6 pacientes (6.25%) de tumor ovárico borderline y 10 (10.4%) de un tumor metastásico. En cuanto a los tumores malignos de ovario, 22 fueron serosos, 2 mucinosos, 3 endometrioides, 10 de células claras, 2 mixtos epiteliales y mesenquimales y un tumor germinal. La sensibilidad del marcador CA125 fue mayor (97.5%), que la sensibilidad del marcador HE4 y que la del Índice ROMA (90% y 95%, respectivamente). Sin embargo, el marcador HE4 demostró la mayor especificidad, con un 87.5%, frente al 62.5 % y 77.5% del CA125 e Índice ROMA. En el caso de las pacientes premenopáusicas, el AUC del marcador HE4 es claramente superior al del CA125 (AUCHE4 PRE= 0.960 [IC 0.909-1.000] vs AUCCA125 PRE= 0.823 [IC 0.705-0.942]). En las pacientes posmenopáusicas, sin embargo, el AUC mayor es el del Índice ROMA (AUC I.R POS= 0.896 [ IC 0.833-0.958]), seguido del AUC del marcador HE4 (AUCHE4 POS= 0.886 [IC 0.778-0.995]) , siendo el menor el AUC del marcador CA125 (AUCCA125 POS= 0.770 [IC 0.627-0.914]). Conclusiones Nuestros resultados muestran, en consonancia con lo publicado hasta ahora, que el marcador HE4 mejora la especificidad del CA125 a la hora de diferenciar entre patología benigna y maligna, presentando además una mejor capacidad diagnóstica en pacientes premenopáusicas que el CA125. El Índice ROMA posee mayor capacidad diagnóstica en pacientes posmenopáusicas. Tanto el marcador HE4 como el Índice ROMA, poseen una mejor capacidad diagnóstica que el Risk of Malignancy Index (RMI) para el diagnóstico diferencial de masas anexiales, según se desprende de los valores de AUC obtenidos, por lo que de acuerdo con la evidencia disponible, podemos concluir que el marcador HE4 y el Índice ROMA superan al marcador CA125 en el diagnóstico diferencial de masas anexiales, siendo herramientas útiles en el diagnóstico del cáncer de ovario.

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de consulta: 29-02-2008, Mitochondria play essential roles in cellular energetic metabolism, the execution of cell death and intracellular calcium and reactive oxygen species signalling. A growing number of human diseases are nowadays associated with the molecular and/or functional alteration of mitochondria. The results reported in this thesis emphasize the role of the mitochondria in cancer biology. In this regard, Otto Warburg reported, as early as in 1924, that the glycolytic phenotype of tumors results from mitochondrial malfunction in the cancer cell. However, his hypothesis has been basically neglected until recently. Herein, we have studied in normal and tumor biopsies derived from the same patients the changes in the expression level of bioenergetic and structural mitochondrial proteins concurrently with the expression of glycolytic markers of the cell, the so-called “bioenergetic signature”. In agreement with previous findings in other carcinomas, the results obtained in squamous carcinomas of the oesophagus support the original Warburg hypothesis because we observed a reduction of the bioenergetic competence of the organelle when compared to normal oesophageal tissue. In contrast, in prostate adenocarcinomas we observed no alterations of the bioenergetic signature what might suggest that carcinogenesis affects the phenotype of mitochondria in a tissue-specific manner. The finding of an alteration in the metabolic proteome of cancer as a common feature of most type of carcinomas led us to consider the “bioenergetic signature” as a tool for the diagnosis and prognosis of cancer patients. Indeed, the use of these markers of metabolism allowed the molecular discrimination of melanomas from its metastasis as well as a group of melanoma patients with worse prognosis. Furthermore, the β-F1/GAPDH ratio provided a significant marker of disease progression for melanoma patients. From the mechanistic point of view, we have studied the effect of oncogenes (RAS, PDGF, AKT and EBV) on the “bioenergetic signature” and rates of cellular glycolysis. We find a variable effect of the different oncogenes in the energetic metabolism of the cell illustrating that tumor progression is linked to changes in the bioenergetic phenotype obtaining that tumor progression selects apparently cells with a higher glycolytic metabolism., Since it appears that alterations in mitochondrial physiology contribute to the Warburg effect, a question arises: which is the advantage and mechanistic contribution of the downregulation of oxidative phosphorylation for the cancer cell? In this regard, we show that the activity of the H+-ATP synthase participates in the execution of cell death by controlling the generation of reactive oxygen species which in turn promote a severe oxidative damage to mitochondrial proteins, favouring in this way the release of apoptogenic molecules from the organelle. These results provide an additional evidence linking metabolism to cell death and support strongly that the acquisition of a Warburg phenotype is another strategy of cancer cells in order ensure its perpetuation. Our knowledge of the basic cell biology and on the timing and mechanism that control the biosynthesis of mitochondrial constituents during progression through the cell cycle of mammalian cells remain largely unknown. In this work we document the timing of the biosynthesis of different mitochondrial constituents during progression through the cell cycle and illustrate the relevance of the control of translation for appropriate biogenesis of mitochondria. In this regard, we show that the 3’UTR of β-mRNA controls the synthesis of the protein at G2/M, a stage when full development of the mitochondrial membrane potential is attained. Moreover, we document the dynamics and morphological changes experimented by mitochondria during mitosis. A long-standing dogma of cellular and evolutionary biology has been that H+-ATP synthases of F-type are exclusively present in the inner membrane of mitochondria of cell of mammals. However, recent reports claim that this complex is localised at the plasma membrane of human hepatocytes and tumor and endothelial cells. Here we show, using four different antibodies raised against the β-chain of the mitochondrial H+-ATP synthase, and various immunolocalitation techniques and subcellular fractionation experiments, that there is no molecular evidence that could support an ectopic expression of the β-chain on the cell-surface of these cells., Este trabajo ha sido realizado en el laboratorio del Doctor José Manuel Cuezva Marcos, Catedrático del Departamento de Biología Molecular del Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), de la Facultad de Ciencias de la Universidad Autónoma de Madrid (Octubre 2001-Septiembre 2005). Durante este periodo, la licenciada Marta Martínez Diez ha disfrutado de una Beca predoctoral del Fondo de Investigaciones Sanitarias del Ministerio de Sanidad y Consumo (Octubre 2001-Julio 2002), asociada al proyecto de investigación 01/380 y de una Beca Predoctoral de Formación de Personal Investigador del Ministerio de Ciencia y Tecnología (Julio 2002-Septiembre 2005), asociada al proyecto de investigación BMC2001-0710.

Article available at http://dx.doi.org/10.1371/journal.pone.0000107, Nowadays, we are facing a renaissance of mitochondria in cancer biology. However, our knowledge of the basic cell biology and on the timing and mechanisms that control the biosynthesis of mitochondrial constituents during progression through the cell cycle of mammalian cells remain largely unknown. Herein, we document the in vivo changes on mitochondrial morphology and dynamics that accompany cellular mitosis, and illustrate the following key points of the biogenesis of mitochondria during progression of liver cells through the cycle: (i) the replication of nuclear and mitochondrial genomes is synchronized during cellular proliferation, (ii) the accretion of OXPHOS proteins is asynchronously regulated during proliferation being the synthesis of b-F1-ATPase and Hsp60 carried out also at G2/M and, (iii) the biosynthesis of cardiolipin is achieved during the S phase, although full development of the mitochondrial membrane potential (DYm) is attained at G2/M. Furthermore, we demonstrate using reporter constructs that the mechanism regulating the accretion of b-F1-ATPase during cellular proliferation is controlled at the level of mRNA translation by the 39UTR of the transcript. The 39UTR-driven synthesis of the protein at G2/M is essential for conferring to the daughter cells the original phenotype of the parental cell. Our findings suggest that alterations on this process may promote deregulated b-F1-ATPase expression in human cancer., M.M-D, G.S. and A.D.O are/were recipients of predoctoral fellowships from the Ministerio de Educación y Ciencia, Spain. This work was supported by grants from the Ministerio de Sanidad (PI041255), Educación y Ciencia (SAF-2005- 4001 and BMC2001-0710)and Fundación Mutua Madrileña, Spain. The CBMSO is the recipient of an institutional grant from Fundación Ramón Areces.

This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Carcinogenesis following peer review. The definitive publisher-authenticated version Carcinogenesis 2006 27(5):925-935 is available at: http://dx.doi.org/10.1093/carcin/bgi315, There is a large body of clinical data documenting that most human carcinomas contain reduced levels of the catalytic subunit of the mitochondrial H+-ATP synthase. In colon and lung cancer this alteration correlates with a poor patient prognosis. Furthermore, recent findings in colon cancer cells indicate that downregulation of the H+-ATP synthase is linked to the resistance of the cells to chemotherapy. However, the mechanism by which the H+-ATP synthase participates in cancer progression is unknown. In this work, we show that inhibitors of the H+-ATP synthase delay staurosporine (STS)-induced cell death in liver cells that are dependent on oxidative phosphorylation for energy provision whereas it has no effect on glycolytic cells. Efficient execution of cell death requires the generation of reactive oxygen species (ROS) controlled by the activity of the H+-ATP synthase in a process that is concurrent with the rapid disorganization of the cellular mitochondrial network. The generation of ROS after STS treatment is highly dependent on the mitochondrial membrane potential and most likely caused by reverse electron flow to Complex I. The generated ROS promote the carbonylation and covalent modification of cellular and mitochondrial proteins. Inhibition of the activity of the H+-ATP synthase blunted ROS production prevented the oxidation of cellular proteins and the modification of mitochondrial proteins delaying the release of cytochrome c and the execution of cell death. The results in this work establish the downregulation of the H+-ATP synthase, and thus of oxidative phosphorylation, as part of the molecular strategy adapted by cancer cells to avoid ROS-mediated cell death. Furthermore, the results provide a mechanistic explanation to understand chemotherapeutic resistance of cancer cells that rely on glycolysis as the main energy provision pathway., G.S. and M.M-D. were supported by pre-doctoral fellowships from the Ministerio de Ciencia y Tecnología. This work was supported by grants from the Ministerio de Sanidad y Consumo (PI041255), Comunidad de Madrid (SAL/0026/2004) and Ministerio de Ciencia y Tecnología (BMC2001-0710). The CBMSO receives an institutional grant from Fundación Ramón Areces.