To investigate the estrogen receptor (ER) expression in cartilage cell in the development of osteoarthritis induced by bilateral ovariectomy in guinea pig and to find their relationship. 30 two-month-old female guinea pigs were randomly divided into two groups (n = 15 each): sham operation (control) group and ovariectomized group (OVX); Scanning electorne microscope (SEM) and transmission electron microscope (TEM) were obtained to analysis the cartilage degeneration of the hind limb knee joint after 6 and 12 weeks of ovariectomy. Dextran-Coated-Charcoal (DCC) was taken to quantitively detect the expression of ER. The serum levels of estrogen and gestone were detected by immune contest assay. The results showed that ER do exist in the cartilages of the guinea pigs, with higher expression in the control group than in OVX group at the same time point (P < 0.05). It was increased also at 12 th week after operation than that of preoperation. The blood serum levels of estrogen and gestone showed a similar tendency to the expression of ER. Joint cartilage degeneration detected by SEM and TEM could be found at 6 th week, but severe degenerative lesions at 12 th week in the OVX group compared with the control group (P < 0.01). The data suggested that bilateral ovariectomy in guinea pig lead to severe osteoarthritis which mighgt be related to the lower serum level of estrogen and the downregulation of the expression of ER in the cartilage also.
Cartilage, Articular/cytology ; Cartilage, Articular/*metabolism ; Chondrocytes/metabolism ; Estrogens/*blood ; Osteoarthritis/*etiology ; Osteoarthritis/metabolism ; Ovariectomy ; Random Allocation ; Receptors, Estrogen/*biosynthesis ; Receptors, Estrogen/genetics

OBJECTIVETo investigate the correlation of prolactin receptor (PRL-R) expression to estrogen receptor (ER) and progesterone receptor (PR) expressions in primary breast cancer.

METHODSFor 130 female patients with breast cancer (median age 46 years), PRL-R expression in the primary tumor was detected by immunohistochemistry, and the correlation between PRL-R and ER/PR expressions was analyzed statistically.

RESULTSPRL-R positivity in the primary tumor was found in 89 of the patients (68.5%), and the positivity rate for PRL-R was positively correlated to ER expression (P<0.05). Further stratification of the patients according to the CerbB-2 status revealed such a correlation only in CerbB-2-positive patients (P<0.05). In the patient cohort, no significant correlation was found in the positivity rate between PRL-R and PR expressions (P>0.05), but in CerbB-2-positive patients, the positivity rate of PRL-R showed a positive correlation to PR expression (P<0.05).

CONCLUSIONThe positive correlations in positivity rate between the PRL-R and ER/PR expressions are found only in CerbB-2 positive patients with breast cancer, and the expressional status of CerbB-2 affects the correlation between PRL-R and ER/PR expression in breast cancer.

Adult ; Aged ; Breast Neoplasms ; metabolism ; Female ; Humans ; Middle Aged ; Receptor, ErbB-2 ; genetics ; metabolism ; Receptors, Estrogen ; metabolism ; Receptors, Progesterone ; metabolism ; Receptors, Prolactin ; metabolism

AIMTo explore the expression of ER and PR mRNAs in endometrium with endometriosis.

METHODSThe rat model of endometriosis was established, and the expression of ER, PR mRNAs in the endometrium was examined by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSThe expression of ER and PR mRNAs in ectopic endometrium was significantly lower than that in eutopic and normal endometrium (P < 0.01). But no difference was observed between eutopic and normal endometrium (P > 0.05). Ratio of ER/PR mRNA in ectopic endometrium was larger than that in eutopic and in normal endometrium (P < 0.01).

CONCLUSIONThe result illuminates that the increased ER plays a vital role in the onset of endometriosis.

Animals ; Endometriosis ; metabolism ; Endometrium ; metabolism ; Female ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Receptors, Estrogen ; genetics ; metabolism ; Receptors, Progesterone ; genetics ; metabolism

Sex hormone estrogen is one of the most active intrinsic angiogenesis regulators; its therapeutic use has been limited due to its carcinogenic potential. Plant-derived phytoestrogens are attractive alternatives, but reports on their angiogenic activities often lack in-depth analysis and sometimes are controversial. Herein, we report a data-mining study with the existing literature, using IPA system to classify and characterize phytoestrogens based on their angiogenic properties and pharmacological consequences. We found that pro-angiogenic phytoestrogens functioned predominantly as cardiovascular protectors whereas anti-angiogenic phytoestrogens played a role in cancer prevention and therapy. This bidirectional regulation were shown to be target-selective and, for the most part, estrogen-receptor-dependent. The transactivation properties of ERα and ERβ by phytoestrogens were examined in the context of angiogenesis-related gene transcription. ERα and ERβ were shown to signal in opposite ways when complexed with the phytoestrogen for bidirectional regulation of angiogenesis. With ERα, phytoestrogen activated or inhibited transcription of some angiogenesis-related genes, resulting in the promotion of angiogenesis, whereas, with ERβ, phytoestrogen regulated transcription of angiogenesis-related genes, resulting in inhibition of angiogenesis. Therefore, the selectivity of phytoestrogen to ERα and ERβ may be critical in the balance of pro- or anti-angiogenesis process.
Angiogenesis Inducing Agents ; metabolism ; Angiogenesis Inhibitors ; metabolism ; Animals ; Gene Expression Regulation ; Humans ; Phytoestrogens ; metabolism ; Receptors, Estrogen ; genetics ; metabolism ; Signal Transduction

A rapid decline in egg production of laying hens begins after 480 d of age. Such a rapid decrease results predominantly from the ovarian aging, accompanied by endocrine changes, decreased yolk synthesis and accumulation, and the reduction in follicles selected into the preovulatory hierarchy. In this study, hens at 90, 150, 280, and 580 d old (D90, D150, D280, and D580, respectively) were compared for yolk precursor formation in the liver to elucidate effects of aging on laying performance. The results showed that liver lipid synthesis increased remarkably in hens from D90 to D150, but decreased sharply at D580 as indicated by the changes in triglyceride (TG) levels. This result was consistent with the age-related changes of the laying performance. The levels of liver antioxidants and total antioxidant capacity decreased significantly in D580 hens and the methane dicarboxylic aldehyde in D580 hens was much higher than that at other stages. The serum 17β-estradiol level increased from D90 to D280, but decreased at D580 (P<0.05). The expression of estrogen receptor α and β mRNAs in the liver displayed similar changes to the serum 17β-estradiol in D580 hens. Expressions of the genes related to yolk precursor formation and enzymes responsible for fat acid synthesis were all decreased in D580 hens. These results indicated that decreased yolk precursor formation in the liver of the aged hens resulted from concomitant decreases of serum 17β-estradiol level, transcription levels of estrogen receptors and critical genes involved in yolk precursor synthesis, and liver antioxidant status.
Age Factors ; Animals ; Antioxidants ; metabolism ; Chickens ; Egg Yolk ; metabolism ; Estradiol ; blood ; Female ; Lipids ; biosynthesis ; Liver ; metabolism ; Oviposition ; Receptors, Estrogen ; genetics

To elucidate the endocrine mechanism of human parturition, the expression of c-Jun and c-Fos mRNA were examined in relation to estrogen receptor (ER) and progesterone receptor (PR) in human myometrium. c-Jun mRNA was detected in all myometrial tissues (n=5) during labor but not before labor (n=5) and in oxytocin-resistant postterm pregnancy (n=3). c-Fos mRNA was detected in only one myometrial tissue from a woman in labor. The distribution and intensity of immunostaining for ER and PR were semiquantitatively scored. During the late pregnancies, no significant difference was seen in the receptor scores for myometrial ER and PR between the patients who experienced labor and those who did not. Receptor scores for ER and PR were significantly lower in postterm pregnancy than in late pregnancy, regardless of the labor status. These data suggest that there are no changes in ER and PR in human myometrium during parturition. On the other hand, postterm pregnancy is associated with low ER and PR. c-Jun, induced during labor without changes in ER and PR, may play a role as a signaling mechanism in human myometrium.
Adult ; Blotting, Northern ; Female ; Genes, jun/genetics* ; Human ; Immunohistochemistry ; Labor/metabolism* ; Myometrium/metabolism* ; Myometrium/cytology ; Pregnancy ; RNA, Messenger/analysis ; Receptors, Estrogen/metabolism* ; Receptors, Progesterone/metabolism* ; Reference Values

OBJECTIVETo investigate the effects of static magnetic fields (SMFs) with different exposure time on the maturation of rat osteoblasts in vitro and the expression of the estrogen receptor (ER) gene.

METHODSThe calvarial osteoblasts were isolated from newborn rats by enzyme digestion and randomly divided into 9 groups after one passage based on the exposure time of the SMFs[0 (control), 0.5 h, 1.0 h, 1.5 h, 2.0 h, 2.5 h, 3.0 h, 3.5 h, and 4.0 h]. The intensity was 3.9 mT in all SMFs. Those without SMFs exposure were used as the controls. The oeteoblasts were observed under the contrast phase microscope on a daily basis. After 48 h, cell proliferation was assayed by MTT method. The osteocalcin contents were measured after exposure to SMFs for 3 d, 6 d, 9 d, and 12 d. ERΑ and ERΒ mRNA expressions were measured by real-time PCR after SMFs treatment for 0 h, 24 h, 48 h, and 72 h.

RESULTSCompared with the controls, the cell proliferation was significantly enhanced in the 2.0-h, 2.5-h, and 3.0-h groups (P<0.05). After SMFs treatment for 6 d, 9 d and 12 d, the 2.5-h group had significantly higher osteocalcin content than the control group did (P<0.05). After SMFs treatment for 0 h and 72 h, elevated ERΑ mRNA expression and reduced ERΒ mRNA expression were observed.

CONCLUSIONExposure to SMFs, regardless of exposure time, is associated with enhanced cell proliferation, increased osteocalcin contents, and altered ERΑ and ERΒ mRNA expressions in opposite directions.

Animals ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Magnetic Fields ; Osteoblasts ; cytology ; metabolism ; Rats ; Receptors, Estrogen ; genetics ; metabolism

OBJECTIVETo investigate the possible mechanism by which estrogen regulates apoptosis through the estrogen receptor.

METHODSBy means of fluorescence immunocytochemistry, the present study investigated the distribution of Bcl-2 and the colocolization of Bcl-2 and ERalpha immunoreactivity in the hippocampus of 10 Alzheimer's disease (AD) patients and 10 aged controls.

RESULTSBcl-2 immunoreactivity was widely distributed in neurons, concentrating predominantly on the subfields CA3 and CA4 in the stratum pyramidale of hippocampus both in controls and in AD patients. Bcl-2 staining in the labeled neuron was observed mainly in the cytoplasm and neuritic processes, but a few nuclei were also positive. Bcl-2 labeling was also detected in the astrocytes mainly in AD, but sparsely in controls. Double-labeled fluorescence immunocytochemistry showed that most Bcl-2-immunolabeled neurons also exhibited positive staining for ERalpha.

CONCLUSIONSEstrogen may function as a regulator of apoptosis to modulate the expression of Bcl-2 in neurons and astrocytes in hippocampus of AD through ERalpha.

Alzheimer Disease ; genetics ; metabolism ; Apoptosis ; Astrocytes ; metabolism ; Estrogen Receptor alpha ; Female ; Hippocampus ; metabolism ; pathology ; Humans ; Neurons ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Receptors, Estrogen ; genetics ; metabolism ; physiology

BACKGROUNDHyaluronidase (Hyase) is an enzyme which hydrolyses hyaluronan (HA), a large nonsulfated glycosaminoglycan. Several genes have been identified to code for hyaluronidases in humans. Its role has only recently been underlined in the invasion of prostate cancer, colonic cancer, and breast cancer. Moreover, the findings were in agreement with some experimental results which showed that HA-derived oligosaccharides had angiogenesis-promoting activity. All these findings prompted us to investigate factors that had been characterized as putative invasive factors in different human breast cancer-derived cell lines.

METHODSWe selected two series of human breast cancer-derived cell lines whose expression of estrogen receptors (ER) was previously published. Hyaluronidase secretion in culture medium and expression of matrix metallo-proteinase (MMP)-9, cathepsin-D (cath-D) and vascular endothelial growth factor (VEGF) by cells were determined. We also investigated cell invasiveness in the Matrigel invasion assay, and studied the capability of cancer cells to promote in vitro formation of tubules by endothelial cells.

RESULTSER(-) cells secreted significantly more hyaluronidase (P < 0.001) and expressed significantly more VEGF (P < 0.01), MMP-9 (P < 0.05) and cath-D (P < 0.0001) than ER(+) cells. Invasion through Matrigel by ER(-) Hyase(+) cells was significantly higher than that by ER(+) Hyase(-) cells (P < 0.05). In both cases, invasion was decreased by heparin (P < 0.05). When ECV-304 endothelial cells were co-cultivated in millicell chambers with cancer cells, ECV-304 cells were induced to form tubules. Tubule formation was demonstrated to be more prominent with ER(-) Hyase(+) cells than with ER(+) Hyase(-) cells (P < 0.05).

CONCLUSIONInvasive features of ER(-) breast cancer cells can be characterized in vitro by an invasive Matrigel assay, as the induction of tubule formation by ECV-304 endothelial cells, higher secretion of hyaluronidase, and higher expression of proteinases MMP-9, cath-D, and the angiogenesis promoting factor VEGF.

Breast Neoplasms ; metabolism ; Cathepsin D ; metabolism ; Cell Line, Tumor ; Humans ; Hyaluronoglucosaminidase ; metabolism ; Immunohistochemistry ; Matrix Metalloproteinase 9 ; metabolism ; Neoplasm Invasiveness ; genetics ; Receptors, Estrogen ; genetics ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo investigate the expression of the miR-155 in human primary breast cancer and its clinical significance.

METHODSFrom February to June 2009, 45 pairs of specimens of human primary breast cancer and matched nontumor breast tissues were collected from the patients who received operation for breast cancer. Real-time polymerase chain reaction (RT-PCR) was used to detect the miR-155 expression in those specimens.

RESULTSThe stem-loop RT-PCR was sensitive and specific enough to detect the expression of the miR-155. The median relative expression of miR-155 was 0.360 in tumor samples, and it was 0.135 in matched nontumor breast tissues, the difference was statistically significant (P < 0.05). It's indicated that the up-regulation of miR-155 expression was associated with advanced TNM clinical stage (median 0.316, 0.358 and 0.417 respectively for stage I, II and III tumor, P = 0.002), lymph node metastasis (median 0.383 and 0.355 respectively for cases with positive and negative lymph nodes, P = 0.034), higher proliferation index [median 0.387 and 0.353 respectively for cases with high proliferation index (Ki67 > 10%) and low proliferation index (Ki67 ≤ 10%), P = 0.019], estrogen receptor-positive (0.367 and 0.318 respectively for cases with positive estrogen receptor and negative group, P = 0.041) and progesterone receptor-positive (0.398 and 0.335 respectively for cases with positive progesterone receptor and negative group, P = 0.029) in patients with breast cancer.

CONCLUSIONSThe expression of miR-155 is up-regulated in primary breast cancer, especially in patients with positive estrogen and progesterone receptor. miR-155 may play an important role in the proliferation, invasion and metastasis of human primary breast cancer, and it could be a indicator in the diagnosis and prognosis of primary breast cancer.

Adult ; Aged ; Breast Neoplasms ; genetics ; metabolism ; pathology ; Estrogen Receptor alpha ; metabolism ; Female ; Humans ; MicroRNAs ; genetics ; metabolism ; Middle Aged ; Receptors, Progesterone ; metabolism