Isabel Torgal

Clinical translation for endometrial cancer stem cells hypothesis

Endometrial cancer is the most frequent gynecological malignancy in developed world. Cancer stem cells (CSC) are recognized as a small proportion of cells among the tumor cell population that are capable of self-renewal, aberrant differentiation, and escape homeostasis. This review aims to systematize the existing evidence of CSC of endometrial cancer and its clinical translation. In endometrial cancer, the cancer stem cell hypothesis has been studied in vitro using the isolation of colony forming units, side population with dye efflux capacity, and tumorospheres. The stem cell markers for endometrial cancer do not have uniform characteristics, albeit CD133 and aldehyde dehydrogenase (ALDH) were being associated with CSC phenotype. The application of endometrial CSC on xenograft models proves the tumorigenic capacity of this small group of cells. The metastatic process has been explained due to epithelial-mesenchymal transition (EMT) in which CSC seems to have a critical role. The chemoresistance is characteristic of CSC that in endometrial cancer has been shown in CSC phenotype and associated with CSC markers. The most ambitious potential for CSC is the development of targeted therapies. Its application on endometrial cancer is still poor, being a future perspective for research.

Signalling pathways involved in oocyte growth, acquisition of competence and activation

Abstract The oocytes primary function is to be fertilised by a spermatozoon in order to create a viable embryo. Oocyte growth and development are initiated during embryogenesis and occur in parallel to follicular development. Factors produced by the oocyte bind to receptors on follicular cells, ensuring follicular development. Oocytes begin meiosis during foetal development and are arrested in prophase I by elevated levels of cyclic adenosine monophosphate (cAMP). Activation of mitogen-activated protein kinases triggers degradation of cAMP, allowing oocyte maturation to proceed. The production of progesterone and prostaglandins during the ovulation process ultimately activates proteases, whose action helps to release the oocyte into the Fallopian tube. Oocyte activation depends on fertilisation and is induced by changes in intracellular calcium levels. Dysregulation of these pathways is involved in the pathogenesis of several diseases including the syndrome of oocyte maturation failure.

Definitive Contraception: Trends in a Ten-year Interval

Objective To evaluate the trends in definitive contraception in a ten-year interval comprising the years 2002 and 2012. Method Retrospective analysis of the tubal sterilization performed in our service in 2002 and 2012, analyzing the demographic characteristics, personal history, previous contraceptive method, definite contraception technique, effectiveness and complications. Results Definitive contraception was performed in 112 women in 2002 (group 1) and in 60 women in 2012 (group 2). The groups were homogeneous regarding age, parity, educational level and personal history. The number of women older than 40 years choosing a definitive method was more frequent in group 1, 49.1% (n = 55); for group 2, the rate was 34.8% (n = 23) (p = 0.04). The time between the last delivery and the procedure was 11.6 ± 6.2 and 7.9 ± 6.4 years (p = 0.014) in 2002 against 2012 respectively. In 2002, all patients performed tubal ligation by laparoscopic inpatient regime. In 2012, the bilateral placement of the Essure (Bayer Corporation, Whippany, NJ, US) device was suggested to 56.1% (n = 37) of the patients, while laparoscopy was suggested to 43.9% (n = 29) of them. All women who underwent laparoscopic sterilization had the procedure successfully completed using silastic rings. The overall bilateral device placement rate for the Essure was 91.6%, with only one complication reported. All Essure procedures were performed in an outpatient setting; for the laparoscopy, this rate was 79% (n = 15). No intentional pregnancies occurred until this date. Conclusions There is a trend in the decrease in definitive contraception over the years in our institution, maybe as a result of the development of long-acting reversible contraceptives. The hysteroscopic procedure has become a frequent option, as it is performed in an office setting without anesthesia, being a well-tolerated, minimal invasive method.

A Case of Endometrial Stromal Sarcoma with Synchronous Bilateral Adenocarcinoma of Ovary

Endometrial stromal tumor is a rare mesenchymal uterine tumor. We report the case of a patient with endometrial stromal sarcoma and concomitant bilateral endometrioid adenocarcinoma of the ovary in the context of pelvic endometriosis. The patient underwent a complete cytoreduction including total hysterectomy and bilateral adnexectomy, pelvic lymphadenectomy, appendicectomy, infracolic omentectomy, and pelvic peritonectomy. This is the first report to our knowledge that describes a synchronous endometrial stromal sarcoma and bilateral endometrioid adenocarcinoma of the ovary.

Phenotypic analysis of breast cell lines – triple negative cells vs expressing hormonal receptors

Breast cancer patients are stratified in 3 groups: expressing hormonal receptors (HR), which respond to therapies targeting estrogen receptors; HER2+, candidates to trastuzumab; and triple negative (TN), for which, despite its more aggressive clinical behavior, chemotherapy is therapy available. In vitro studies proved that cells subjected to specific growth factors form spherical colonies of stem-cells in suspension designated mammospheres (MS). The aim of this work is to assess the capacity to form MS in TN (HCC1806) comparing with HR+ (MCF7) breast cancer cell lines. Cell lines were propagated according to ATCC. MS forming protocol consisted on cell culturing in DMEMF12 supplemented with bFGF and EGF. Media was renewed every 2 days. Flow cytometry analysis, with antibodies anti-CD44, anti-CD24 and anti CD133 was made. Microscopic observation showed a differential phenotype. HR+ cells formed spherical colonies in suspension while TN maintained adherent appearing only a few groups of MS. This may be related with late recurrence. Controls of both cell lines analyzed showed a low CD44 markup. For both cell lines CD133 did not show significant changes. HR+ cells had higher expression of CD44 and CD133 when compared with TN. In TN cells was identified 2 populations of cells in suspension. The major one was CD44+ and in 1% this expression was even more relevant and may be representative of a progenitor cell population. The HR+ showed stronger staining for CD24 than TN. The HR+ also differentiated 2 populations, a major one CD44+ and 9% with minor expression of CD44. The results suggest a significant fraction of HR+ harboring CD44+, representing a phenotype of progenitor cells.

In vivo pulmonary metastatic profile of breast cancer cell lines expressing hormonal receptors versus triple negative

Breast cancer metastized to lungs is a challenge considering clinical management and molecular processes. The interaction between tumor cells and lung environment as well as the influence of hormonal receptor (HR) are a question of debate. The aim of this study is the characterization of pulmonary metastatic spread in vivo of breast cancer cell lines that express HR comparing with triple negative (TN) after injection in the tail vein. It was performed injection in the tail vein of female mice Balb/c nude with 1.5×106 cells of each breast cancer cell line (MCF7 and HCC1806) previously labeled with 99mTc-HMPAO. Imagiological studies with 99mTc-HMDP and 99mTc-MIBI were performed between 7th and 8th weeks and then sacrificed. The lungs were submitted to histological image analysis focusing on regions of interest (ROI), in order to obtain lesion areas. Tumor cells injected labeled with 99mTc-HMPAO showed a preference embolization to the lungs. The ROI analysis of imagiological studies with 99mTc-HMDP and 99mTc- MIBI did not reveal significant differences according to each cell type. Histology showed metastatic lung foci in all animals injected. On one hand, the number of lung foci was not significantly different considering MCF7 and HCC1806 injection. On the other hand, the mean area of lung metastasis in MCF7 cases were significantly higher than in HCC1806 (p = 0.023). The mice injected with HR positive breast cancer cells in the tail vein were associated with higher lung metastatic areas than TN cells. This emphasizes the influence of HR in the expression of growth factors and pulmonary neovascularization that is not still delineated.