17 research outputs found
Le cancer épithélial des ovaires à cellules claires et de type mucineux exprime un niveau élevé de HYAL-1 : corrélation inverse avec l’expression des récepteurs d’estrogène et de progestérone
Le cancer épithélial des ovaires (CEO) est classifié en sous types histopathologiques identifiés tel que séreux, endométrioide, à cellules claires et mucineux. Une analyse génétique réalisée au niveau moléculaire a suggéré un rôle pour des gènes suppresseurs de tumeur localisés sur le bras court du chromosome 3p21.3 dans la pathogénèse du CEO de type séreux. Notre objectif était d’évaluer le profil d’expression de HYAL-1, localisé dans cette même région, dans les différents sous types du CEO, et de vérifier une éventuelle corrélation avec l’expression des récepteurs d’hormones stéroïdiennes. Pour se faire, nous avons analysé par RT-PCR quantitative l’expression de l’ARNm de HYAL-1, des récepteurs d’estrogène (ER-α et ER-β) et du récepteur de progestérone (PR) dans des échantillons de tissus extraits de tumeurs du CEO provenant de deux cohortes indépendantes et dans des lignées cellulaires. Nous avons également réalisé des analyses bioinformatiques à partir de l’expression de ces gènes en ayant recours à une base de données de microarray disponible en ligne et ouverte au public. Par la suite, nous avons mesuré l’activité enzymatique de HYAL-1 dans des lignées cellulaires du CEO et dans des échantillons de plasma. Nos résultats ont montré que l’expression de l’ARNm de HYAL-1 était élevée dans le type à cellules claires et mucineux mais non dans les types séreux et endométrioides, autant dans les échantillons sains que de ceux provenant de tumeurs bénignes. De façon cohérente, le niveau d’ARNm et l’activité enzymatique de HYAL-1 étaient élevés dans les lignées cellulaires à cellules claires et mucineuses. Nous avons aussi démontré qu’il y avait une corrélation inverse entre
les niveaux de l’ARNm de HYAL-1 et ceux d’ER-α et PR dans les échantillons de tissus de CEO du type mucineux et à cellules claires. De façon similaire, nous avons noté que l’activité de HYAL-1 était élevée dans le plasma de ces mêmes patients. En conséquence nos travaux proposent HYAL-1 en tant que biomarqueur potentiel dans le cas des CEO de type à cellules claires et mucineux présentant un faible niveau d’expression d’ER-α et PR.Epithelial ovarian cancer (EOC) is morphologically heterogeneous being classified as serous, endometrioid, clear cell, or mucinous. Molecular genetic analysis has suggested a role for tumor suppressor genes located on chromosome 3p in the pathogenesis of serous EOC. Our objective was to evaluate the expression of HYAL-1, located at chromosome 3p21.3, in these EOC subtypes, and to verify a possible correlation with the expression of steroid hormone receptors. We analyzed the mRNA expression of HYAL-1, estrogen receptor (ER)-α, ER-β and progesterone receptor (PR) in EOC tumor samples and cell lines using quantitative RT-PCR. We also performed bioinformatics analyses on the expression of these genes using a publicly available microarray dataset. HYAL-1 enzyme activity was measured in EOC cell lines and in plasma samples from patients. We found that HYAL-1 mRNA expression was elevated in clear cell and mucinous EOC tissue samples, but not in serous and endometrioid samples, normal ovaries or benign tumors. Significantly, similar results were obtained by two different techniques and with tissue sample cohorts from two independent institutions. Concordantly, HYAL-1 mRNA levels and enzyme activity were elevated in EOC cell lines derived from clear cell and mucinous subtypes. We also showed that HYAL-1 mRNA was inversely correlated to that of ER-α and PR, but not to that of ER-β, specifically in clear cell and mucinous EOC tissue samples. HYAL-1 activity was also high in the plasma of patients with these EOC subtypes. Our results suggest Hyaluronidase-1 as a potential target/biomarker for clear cell and mucinous EOCs and especially in tumors with low levels of ER-α and PR
Effect of Calotropis procera on the Proximate Composition and Potential Toxicity of Wagashi (Traditional Cheese) in Benin
The Peulh cheese, locally known as Wagashi, is a popular local milk product in Benin. The most important step in the production of Wagashi is the coagulation of the milk into cheese using fresh leaves and stems of Calotopis procera. Calotropis procera is a well-known traditional medicinal plant in the world and, particularly utilized in West Africa in the treatment of many infections. Despite the importance associated with this plant, it has been shown that the plant contains toxic substances that can threaten human health. To define the properties of this plant, we embarked on determining the phytochemical composition of Calotropis procera, Wagashi and whey, evaluation of the value added by the coagulant by comparing the proximate composition of the milk to the one of the wagashi as well as assess the safety of the Wagashi and the whey. Milk from three different breeds of cows (Girolando, Borgou and Lagunaire) were collected from Benin, and used to prepare the cheese and whey evaluated in this study. Our results revealed that there is significant variation (p≤0.05) between the gross composition of the milk, Wagashi and whey. The moisture content vary from 84.19% for milk to 62.47% to the cheese, the ash content vary from 0.67% in milk to 1.41% for cheese while the protein content vary from 2.44% in milk to 8.18% for cheese while the lactose vary from 2.02% to 3.0% for cheese; as for the carbohydrate content decrease from 6.12% in the milk to 4% in the cheese for the breed Girolando. The moisture content vary from 81.68% for milk to 57.34% to the cheese, the ash content vary from 0.63% in milk to 1.46% for cheese while the protein content vary from 1.73% in milk to 8.03% for cheese, the fat content vary from 7.5% to 4.52% for cheese while the lactose vary from 2.37% to 2.90% for cheese; as for the carbohydrate content decrease from 5.38% in the milk to 3.77% in the cheese for the breed Borgou. The moisture content vary from 84.19% for milk to 62.74% to the cheese, the ash content vary from 0.67% in milk to 1.41% for cheese while the protein content vary from 2.44% in milk to 8.18% for cheese, the fat content vary from 5.10% to 7.11% for cheese while the lactose vary from 2.02% to 3% for cheese; as for the carbohydrate content decrease from 6.12% in the milk to 4% in the cheese for the breed Lagunaire. However, the variance in composition is dependent on the breed from which the milk was obtained. Besides, the phytochemicals present in Calotropis procera such as alkaloids, flavonoids, tannins, cardiac glycosides, phenols, saponins and steroids were not detected in both the cheese and whey. We deduced that the process of Wagashi and/or whey processing denatures the phytochemicals, thus assuring the safety of the products. However, further studies exploiting more sensitive analytical methods are required to confirm these findings Keywords: Milk, cheese, whey, proximate, Calotropis procera, phytochemical analysi
Alcohol Regulates Genes that Are Associated with Response to Endocrine Therapy and Attenuates the Actions of Tamoxifen in Breast Cancer Cells
Hereditary, hormonal, and behavioral factors contribute to the development of breast cancer. Alcohol consumption is a modifiable behavior that is linked to increased breast cancer risks and is associated with the development of hormone-dependent breast cancers as well as disease progression and recurrence following endocrine treatment. In this study we examined the molecular mechanisms of action of alcohol by applying molecular, genetic, and genomic approaches in characterizing its effects on estrogen receptor (ER)-positive breast cancer cells. Treatments with alcohol promoted cell proliferation, increased growth factor signaling, and up-regulated the transcription of the ER target gene GREB1 but not the canonical target TFF1/pS2. Microarray analysis following alcohol treatment identified a large number of alcohol-responsive genes, including those which function in apoptotic and cell proliferation pathways. Furthermore, expression profiles of the responsive gene sets in tumors were strongly associated with clinical outcomes in patients who received endocrine therapy. Correspondingly, alcohol treatment attenuated the anti-proliferative effects of the endocrine therapeutic drug tamoxifen in ER-positive breast cancer cells. To determine the contribution and functions of responsive genes, their differential expression in tumors were assessed between outcome groups. The proto-oncogene BRAF was identified as a novel alcohol- and estrogen-induced gene that showed higher expression in patients with poor outcomes. Knock-down of BRAF, moreover, prevented the proliferation of breast cancer cells. These findings not only highlight the mechanistic basis of the effects of alcohol on breast cancer cells and increased risks for disease incidents and recurrence, but may facilitate the discovery and characterization of novel oncogenic pathways and markers in breast cancer research and therapeutics
Emerging roles for hyaluronidase in cancer metastasis and therapy
Hyaluronidases are a family of five human enzymes that have been differentially implicated in the progression of many solid tumor types, both clinically and in functional studies. Advances in the past five years have clarified many apparent contradictions, (1) by demonstrating that specific hyaluronidases have alternative substrates to hyaluronan (HA) or do not exhibit any enzymatic activity, (2) that high molecular weight HA polymers elicit signaling effects that are opposite those of the hyaluronidase-digested HA oligomers, and (3) that it is actually the combined overexpression of HA synthesizing enzymes with hyaluronidases that confers tumorigenic potential. This review examines the literature supporting these conclusions and discusses novel mechanisms by which hyaluronidases impact invasive tumor cell processes. In addition, a detailed structural and functional comparison of the hyaluronidases is presented with insights into substrate selectivity and potential for therapeutic targeting. Finally, technological advances in targeting hyaluronidase for tumor imaging and cancer therapy are summarized
Subtype specific elevated expression of hyaluronidase-1 (HYAL-1) in epithelial ovarian cancer.
BACKGROUND:Epithelial ovarian cancer (EOC) is morphologically heterogeneous being classified as serous, endometrioid, clear cell, or mucinous. Molecular genetic analysis has suggested a role for tumor suppressor genes located at chromosome 3p in serous EOC pathogenesis. Our objective was to evaluate the expression of HYAL1, located at chromosome 3p21.3, in these EOC subtypes, and to investigate its correlation with the expression of steroid hormone receptors. METHODOLOGY/PRINCIPAL FINDINGS:We determined the mRNA expression of HYAL1, estrogen receptor (ER)-α, ERβ and progesterone receptor (PR) in EOC tumor samples and cell lines using quantitative RT-PCR. We also examined the expression of these genes in a publicly available microarray dataset. HYAL-1 enzyme activity was measured in EOC cell lines and in plasma samples from patients. We found that HYAL1 mRNA expression was elevated in clear cell and mucinous EOC tissue samples, but not in serous and endometrioid samples, normal ovaries or benign tumors. Similar results were obtained by two different techniques and with tissue sample cohorts from two independent institutions. Concordantly, HYAL1 mRNA levels and enzymatic activity were elevated only in EOC cell lines derived from clear cell and mucinous subtypes. We also showed that HYAL1 mRNA was inversely correlated to that of ERα specifically in clear cell and mucinous EOCs. Additionally, ectopic expression of ERα in a clear cell EOC cell line (ER- and PR-negative) induced 50% reduction of HYAL1 mRNA expression, supporting a role of ERα in HYAL1 gene regulation. Significantly, HYAL-1 activity was also high in the plasma of patients with these EOC subtypes. CONCLUSIONS/SIGNIFICANCE:This is the first report showing high HYAL-1 levels in EOC and demonstrating HYAL1 gene repression by ERα. Our results identify Hyaluronidase-1 as a potential target/biomarker for clear cell and mucinous EOCs and especially in tumors with low ERα levels
Alcohol increases cell proliferation in an estrogen-dependent manner, promotes the activation of ERK1/2, as well as known ER target genes.
<p>(A), Trypan blue exclusion assays demonstrate that estrogen potentiates cell proliferation increases by alcohol. DMSO treated cells are not statistically different from DMSO and alcohol cotreatment. (B), MTS assays measure statistically significant increases in metabolic rate at 21.7, 43.4 and 65.1 mmol/L ethanol concentrations. Treatment with 86.8 mmol/L EtOH did not result in an increase in cell proliferation. (C) Alcohol promotes the phosphorylation of ERK1/2, a key effector of growth factor signaling and of G1-S progression, regardless of estrogen treatment. Quantification comprises data of experiments in triplicate. (D) The effect of alcohol was tested on ER responsive genes TFF1/pS2 and GREB1 in MCF-7 cells. Only GREB1 responds to alcohol treatment, suggesting a possible overlap between cellular estrogen signaling and alcohol response.</p
Alcohol regulates BRAF, an effector of growth factor signaling, and promotes estrogen-dependent and–independent growth.
<p>(A), Microarray validation demonstrates subtle but highly reproducible effects on gene expression of down-regulated and up-regulated genes. (B) BRAF is up-regulated at the protein level by alcohol and estrogen treatment. (C) BRAF is targetable with siRNA knockdown for functional studies. MTS assays demonstrate the anti-proliferative effect of BRAF knockdown on MCF-7 cells, suggesting that BRAF promotes basal cell proliferation in the absence of estradiol, increases estrogen-dependent growth, and potentiates some of the cell’s response to ethanol.</p
High BRAF expression levels correlated ER+ endocrine treated patients with poor prognosis and response to therapy.
<p>(A) BRAF is expressed at higher levels in patients who experience poor disease outcomes as compared to those who did not experience an adverse event. (B) BRAF expression levels separate patients into different DFS groups with nearly significant p-value (<i>p</i> = 0.074). Statistically different (C) DMFS and (D) DSS groups are observed in ER+ endocrine treated patients based on high expression levels of BRAF.</p