Progestin suppresses matrix metalloproteinase production in endometrial cancer

The Role of Fractalkine in the Regulation of Endometrial Iron Metabolism in Iron Deficiency

Iron is a crucial element in the human body. Endometrial iron metabolism is implicated in endometrium receptivity and embryo implantation. Disturbances of the maternal as well as the endometrial iron homeostasis, such as iron deficiency, can contribute to the reduced development of the fetus and could cause an increased risk of adverse pregnancy outcomes. Fractalkine is a unique chemokine that plays a role in the communication between the mother and the fetus. It has been demonstrated that FKN is involved in the development of endometrial receptivity and embryo implantation, and it functions as a regulator of iron metabolism. In the present study, we examined the effect of FKN on the iron metabolism of HEC-1A endometrial cells in a state of iron deficiency mediated by desferrioxamine treatment. Based on the findings, FKN enhances the expression of iron metabolism-related genes in iron deficiency and modifies the iron uptake via transferrin receptor 1 and divalent metal transporter-1, and iron release via ferroportin. FKN can activate the release of iron from heme-containing proteins by elevating the level of heme oxygenase-1, contributing to the redistribution of intracellular iron content. It was revealed that the endometrium cells express both mitoferrin-1 and 2 and that their levels are not dependent on the iron availability of the cells. FKN may also contribute to maintaining mitochondrial iron homeostasis. FKN can improve the deteriorating effect of iron deficiency in HEC-1A endometrium cells, which may contribute to the development of receptivity and/or provide iron delivery towards the embryo.

Regulation of progesterone receptor expression in endometriosis, endometrial cancer, and breast cancer by estrogen, polymorphisms, transcription factors, epigenetic alterations, and ubiquitin-proteasome system

The uterus and breasts are hormone-responsive tissues. Progesterone and estradiol regulate gonadotropin secretion, prepare the endometrium for implantation, maintain pregnancy, and regulate the differentiation of breast tissue. Dysregulation of these hormones causes endometriosis, endometrial cancer, and breast cancer, damaging the physical and mental health of women. Emerging evidence has shown that progesterone resistance or elevated progesterone activity is the primary hormonal substrate of these diseases. Since progesterone acts through its specific nuclear receptor, the abnormal expression of the progesterone receptor (PR) dysregulates progesterone function. This review discusses the regulatory mechanisms of PR expression in patients with endometriosis, and endometrial or breast cancer, including estrogen, polymorphisms, transcription factors, epigenetics, and the ubiquitin-proteasome system. (1) Estrogen promotes the expression of PRA (a PR isoform) mRNA and protein through the interaction of estrogen receptors (ERs) and Sp1 with half-ERE/Sp1 binding sites. ERs also affect the binding of Sp1 and Sp1 sites to promote the expression of PRB (another PR isoform)(2) PR polymorphisms, mainly PROGINS and + 331 G/A polymorphism, regulate PR expression by affecting DNA methylation and transcription factor binding. (3) The influence of epigenetic alterations on PR expression occurs through DNA methylation, histone modification, and microRNA. (4) As one of the main protein degradation pathways in vivo, the ubiquitin-proteasome system (UPS) regulates PR expression by participating in protein degradation. These mechanisms may provide new molecular targets for diagnosing and treating endometriosis, endometrial, and breast cancer.

Progestin Resistance and Corresponding Management of Abnormal Endometrial Hyperplasia and Endometrial Carcinoma

With a younger tendency in morbidity age, endometrial cancer (EC) incidence has grown year after year. Worse, even more commonly occurring is endometrial hyperplasia (EH), which is a precancerous endometrial proliferation. For young women with early EC and EH who want to preserve fertility, progestin therapy has been utilized as a routine fertility-preserving treatment approach. Nevertheless, progestin medication failure in some patients is mostly due to progestin resistance and side effects. In order to further analyze the potential mechanisms of progestin resistance in EH and EC, to provide theoretical support for effective therapeutic strategies, and to lay the groundwork for searching novel treatment approaches, this article reviews the current therapeutic effects of progestin in EH and EC, as well as the mechanisms and molecular biomarkers of progestin resistance, and systematically expounds on the potential therapeutic methods to overcome progestin resistance.

Medroxyprogesterone Acetate Impairs Amyloid Beta Degradation in a Matrix Metalloproteinase-9 Dependent Manner

Despite the extensive use of hormonal methods as either contraception or menopausal hormone therapy (HT), there is very little known about the potential effects of these compounds on the cellular processes of the brain. Medroxyprogesterone Acetate (MPA) is a progestogen used globally in the hormonal contraceptive, Depo Provera, by women in their reproductive prime and is a major compound found in HT formulations used by menopausal women. MPA promotes changes in the circulating levels of matrix metalloproteinases (MMPs), such as MMP-9, in the endometrium, yet limited literature studying the effects of MPA on neurons and astroglia cells has been conducted. Additionally, the dysregulation of MMPs has been implicated in the pathology of Alzheimer's disease (AD), where inhibiting the secretion of MMP-9 from astroglia reduces the proteolytic degradation of amyloid-beta. Thus, we hypothesize that exposure to MPA disrupts proteolytic degradation of amyloid-beta through the downregulation of MMP-9 expression and subsequent secretion. To assess the effect of progestins on MMP-9 and amyloid-beta, in vitro, C6 rat glial cells were exposed to MPA for 48 h and then the enzymatic, secretory, and amyloid-beta degrading capacity of MMP-9 was assessed from the conditioned culture medium. We found that MPA treatment inhibited transcription of MMP-9, which resulted in a subsequent decrease in the production and secretion of MMP-9 protein, in part through the glucocorticoid receptor. Additionally, we investigated the consequences of amyloid beta-degrading activity and found that MPA treatment decreased proteolytic degradation of amyloid-beta. Our results suggest MPA suppresses amyloid-beta degradation in an MMP-9-dependent manner, in vitro, and potentially compromises the clearance of amyloid-beta in vivo.

From epidemiology and neurodevelopment to antineoplasticity. Medroxyprogesterone reduces human glial tumor growth in vitro and C6 glioma in rat brain in vivo

OBJECTIVE

Glial tumor growth may accelerate during gestation, but epidemiological studies consistently demonstrated that parousity reduces life long risk of glial tumors. Pregnancy may also accelerate growth of medulloblastoma and meningioma, but parousity does not confer protection against these tumors. We were the first to show that medroxyprogesterone acetate (MPA) reduces rat C6 glioma growth in vitro. Now we aimed to determine the effects of MPA on human brain cancers (particularly glioblastoma) in vitro and C6 glioma in vivo.

PATIENTS AND METHODS

We evaluated the effects of MPA on: i) monolayer growth of human U87 and U251 glioblastoma, ii) 3D-spheroid growth and invasion of C6 rat glioma and human U251 glioma, iii) interactions with PI3-Kinase inhibitors and coxsackie-adenovirus receptor (CAR) in modifying 3D-spheroid invasion of glioma.

RESULTS

MPA at low doses (3.25-13 μM) insignificantly stimulated and at high doses (above 52 μM) strongly suppressed the growth of human U87 and U251 cells in vitro. MPA also binds to glucocorticoid receptors similar to dexamethasone (Dex) and unexpectedly, PI3-Kinase inhibitors at low doses suppressed anti-invasive efficacies of MPA and Dex. MPA exerted higher invasion-inhibitory effects on CAR-expressing human glioma cells. Lastly, MPA suppressed growth of C6 glioma implanted into rat brain.

CONCLUSION

Progesterone analogues deserve to be studied in future experimental models of high grade glial brain tumors.

Progesterone and calcitriol reduce invasive potential of endometrial cancer cells by targeting ARF6, NEDD9 and MT1-MMP

Previously, we have demonstrated that progesterone and calcitriol synergistically inhibit growth of endometrial and ovarian cancer by enhancing apoptosis and causing cell cycle arrest. Metastasis is the main reason of mortality in cancer patients. Activation of ADP-Ribosylation Factor 6 (ARF6), Neural Precursor cell expressed Developmentally Downregulated 9 (NEDD9), and Membrane-Type-1 Matrix Metalloproteinase (MT1-MMP) have been implicated in promoting tumor growth and metastasis. We examined the effects of progesterone, calcitriol and progesterone-calcitriol combination on metastasis promoting proteins in endometrial cancer. Expression of ARF6, NEDD9, and MT1-MMP was enhanced in advanced-stage endometrial tumors and in cancer cell lines compared to normal tissues and immortalized EM-E6/E7-TERT endometrial epithelial cells. Knockdown of these proteins significantly inhibited the invasiveness of the cancer cells. The expression levels of all three proteins was reduced with progesterone and progesterone-calcitriol combination treatment, whereas calcitriol alone showed no effect on their expression but moderately decreased MT1-MMP activity. Fluorescence microscopy showed membrane expression of MT1-MMP in vehicle and calcitriol-treated endometrial cancer cells. However, progesterone and calcitriol-progesterone combination treatment revealed MT1-MMP in the cytoplasm. Furthermore, progesterone and calcitriol reduced the activity of MT1-MMP, MMP-9, and MMP-2. In addition, invadopodia regulatory proteins were attenuated in both progesterone and progesterone-calcitriol combination treated cells as well as in MT1-MMP knockdown cells. Thus, targeting the aberrant MT1-MMP signaling with progesterone-calcitriol may be a novel approach to impede MT1-MMP mediated cancer dissemination and may have therapeutic benefits for endometrial cancer patients.

Dual-specificity Phosphatase 1 Deficiency Induces Endometrioid Adenocarcinoma Progression via Activation of Mitogen-activated Protein Kinase/Extracellular Signal-regulated Kinase Pathway

Background:

Previously, we reported that dual-specificity phosphatase 1 (DUSP1) was differentially expressed in endometrioid adenocarcinoma (EEA). However, the role of DUSP1 in EEA progression and the relationship between DUSP1 and medroxyprogesterone (MPA) are still unclear.

Methods:

The expression of DUSP1 in EEA specimens was detected by immunohistochemical analysis. The effect of DUSP1 on cell proliferation was analyzed by Cell Counting Kit 8 and colony formation assay, and cell migration was analyzed by transwell assay. MPA-induced DUSP1 expression in EEA cells was measured by Western blot.

Results:

DUSP1 expression was deficient in advanced International Federation of Gynecology and Obstetrics stage, high-grade and myometrial invasive EEA. In EEA cell lines (Hec1A, Hec1B, RL952, and Ishikawa), the DUSP1 expression was substantially higher in Ishikawa cells than in other cell lines (P < 0.05). Knockdown of DUSP1 promoted Ishikawa cells proliferation, migration, and activation of mitogen-activated protein kinases/extracellular signal-regulated kinase (MAPK/Erk) pathway. MPA-induced DUSP1 expression and inhibited MAPK/Erk pathway in Ishikawa cells.

Conclusions:

Our data suggest that DUSP1 deficiency promotes EEA progression via MAPK/Erk pathway, which may be reversed by MPA, suggesting that DUSP1 may serve as a potential therapeutic target for the treatment of EEA.

Role of nuclear progesterone receptor isoforms in uterine pathophysiology

BACKGROUND

Progesterone is a key hormonal regulator of the female reproductive system. It plays a major role to prepare the uterus for implantation and in the establishment and maintenance of pregnancy. Actions of progesterone on the uterine tissues (endometrium, myometrium and cervix) are mediated by the combined effects of two progesterone receptor (PR) isoforms, designated PR-A and PR-B. Both receptors function primarily as ligand-activated transcription factors. Progesterone action on the uterine tissues is qualitatively and quantitatively determined by the relative levels and transcriptional activities of PR-A and PR-B. The transcriptional activity of the PR isoforms is affected by specific transcriptional coregulators and by PR post-translational modifications that affect gene promoter targeting. In this context, appropriate temporal and cell-specific expression and function of PR-A and PR-B are critical for normal uterine function.

METHODS

Relevant studies describing the role of PRs in uterine physiology and pathology (endometriosis, uterine leiomyoma, endometrial cancer, cervical cancer and recurrent pregnancy loss) were comprehensively searched using PubMed, Cochrane Library, Web of Science, and Google Scholar and critically reviewed.

RESULTS

Progesterone, acting through PR-A and PR-B, regulates the development and function of the endometrium and induces changes in cells essential for implantation and the establishment and maintenance of pregnancy. During pregnancy, progesterone via the PRs promotes myometrial relaxation and cervical closure. Withdrawal of PR-mediated progesterone signaling triggers menstruation and parturition. PR-mediated progesterone signaling is anti-mitogenic in endometrial epithelial cells, and as such, mitigates the tropic effects of estrogen on eutopic normal endometrium, and on ectopic implants in endometriosis. Similarly, ligand-activated PRs function as tumor suppressors in endometrial cancer cells through inhibition of key cellular signaling pathways required for growth. In contrast, progesterone via PR activation appears to increase leiomyoma growth. The exact role of PRs in cervical cancer is unclear. PRs regulate implantation and therefore aberrant PR function may be implicated in recurrent pregnancy loss (RPL). PRs likely regulate key immunogenic factors involved in RPL. However, the exact role of PRs in the pathophysiology of RPL and the use of progesterone for therapeutic benefit remains uncertain.

CONCLUSIONS

PRs are key mediators of progesterone action in uterine tissues and are essential for normal uterine function. Aberrant PR function (due to abnormal expression and/or function) is a major cause of uterine pathophysiology. Further investigation of the underlying mechanisms of PR isoform action in the uterus is required, as this knowledge will afford the opportunity to create progestin/PR-based therapeutics to treat various uterine pathologies.

Progesterone action in endometrial cancer, endometriosis, uterine fibroids, and breast cancer

Progesterone receptor (PR) mediates the actions of the ovarian steroid progesterone, which together with estradiol regulates gonadotropin secretion, prepares the endometrium for implantation, maintains pregnancy, and differentiates breast tissue. Separation of estrogen and progesterone actions in hormone-responsive tissues remains a challenge. Pathologies of the uterus and breast, including endometrial cancer, endometriosis, uterine fibroids, and breast cancer, are highly associated with estrogen, considered to be the mitogenic factor. Emerging evidence supports distinct roles of progesterone and its influence on the pathogenesis of these diseases. Progesterone antagonizes estrogen-driven growth in the endometrium, and insufficient progesterone action strikingly increases the risk of endometrial cancer. In endometriosis, eutopic and ectopic tissues do not respond sufficiently to progesterone and are considered to be progesterone-resistant, which contributes to proliferation and survival. In uterine fibroids, progesterone promotes growth by increasing proliferation, cellular hypertrophy, and deposition of extracellular matrix. In normal mammary tissue and breast cancer, progesterone is pro-proliferative and carcinogenic. A key difference between these tissues that could explain the diverse effects of progesterone is the paracrine interactions of PR-expressing stroma and epithelium. Normal endometrium is a mucosa containing large quantities of distinct stromal cells with abundant PR, which influences epithelial cell proliferation and differentiation and protects against carcinogenic transformation. In contrast, the primary target cells of progesterone in the breast and fibroids are the mammary epithelial cells and the leiomyoma cells, which lack specifically organized stromal components with significant PR expression. This review provides a unifying perspective for the diverse effects of progesterone across human tissues and diseases.

Progesterone and calcitriol attenuate inflammatory cytokines CXCL1 and CXCL2 in ovarian and endometrial cancer cells

Cytokines/chemokines are key players in cancer-related inflammation. Increasing evidence suggests that chemokines produced by tumor cells are the mediators of metastasis. Thus, agents that can downregulate chemokines expression have potential against cancer metastasis. We have previously shown inhibition of ovarian and endometrial cancer cell growth with progesterone and calcitriol. In the present study, we evaluated the effect of these two agents on the expression of inflammatory genes. Using a RT-PCR array of inflammatory cytokines/chemokines and their receptors, we found a marked attenuation of CXCL1 and CXCL2 (GRO-α and -β) in cancer cells by both treatments. Knockdown of NFκB resulted in a reduced expression of CXCL1 and CXCL2 and the inhibitory effect of progesterone and calcitriol on the expression of chemokines was abrogated in NFκB-silenced cancer cells. Silencing of IκBα increased the expression of CXCL1 and CXCL2 in cancer cells, which can be attributed to the increased activation of NFκB-p65, caused by the lack of its inhibitor. Progesterone and calcitriol-induced inhibition was abolished in IκBα-knockdown cells. Our results demonstrate that suppression of IκBα phosphorylation by progesterone and calcitriol contributes to the reduced expression of CXCL1 and CXCL2. Downregulation of CXCL1 and CXCL2 was associated with a marked inhibition of metastasis-promoting genes. Overall, our results indicate that progesterone and calcitriol inhibit IκBα phosphorylation, NFκB activation, and the expression of NFκB regulated metastasis promoting genes. These results provide attractive data for the possible use of progesterone and calcitriol in the management of endometrial and ovarian tumors.

Transforming growth factor β1 (TGFβ1) and progesterone regulate matrix metalloproteinases (MMP) in human endometrial stromal cells

CONTEXT

Menstruation is preceded by progesterone withdrawal and endometrial matrix remodeling predominantly through induction of matrix metalloproteinases (MMP) and recruitment of invading neutrophils.

DESIGN

Using endometrial tissues from women during various phases of the menstrual cycle, we found that MMP2, MMP9, and MMP11 were up-regulated in the late secretory phase/premenstrual phase. Because TGFβ-responsive genes were also up-regulated in endometrium during this time, we tested the hypothesis that TGFβ1 and progesterone regulate expression of MMP in human endometrial stromal cells (HESC).

RESULTS

Treatment of HESC with TGFβ1 resulted in marked increases in MMP2 and MMP11 mRNA and pro- and active MMP2 activity. Progesterone inhibited TGFβ1-induced stimulation of MMP2 and MMP11 through its nuclear hormone receptors. Interestingly, TGFβ1 also decreased progesterone receptor (PR)-A and PR-B in HESC with a more pronounced effect on PR-A.

CONCLUSIONS

These data support the hypothesis that TGFβ1 has endogenous anti-progestational effects in HESC and that the opposing effects of progesterone and TGFβ1 are important in regulation of matrix integrity in human endometrium.

The role of progesterone and its receptor on cyclin G1 expression in endometrial carcinoma cells

Cyclin G1 protein is expressed in normal endometrial epithelial cells in a progesterone-dependent manner. It is an important mediator of the inhibiting effect of progesterone on cell proliferation. Moreover, the expression of cyclin G1 is also found to be decreased in human endometrial carcinoma cells (ECCs). To study the mechanism of decrease in the expression levels of cyclin G1, 3 ECC cell lines, Ishikawa, HEC-1-B, and KLE cells were treated with progesterone (P(4)). The KLE cells, in which progesterone receptor (PR) expression was absent, were transfected with PR-expressing plasmid before treatment with P(4). The results showed that cyclin G1 expression increased in Ishikawa and HEC-1-B cells after treatment with P(4), additionally the cell proliferation was suppressed but not in KLE cells. When the PR-expressing plasmid was transfected into KLE cells, the effect of P(4) was restored. Our data suggest that the deficiency of progesterone and its receptors is an important cause of the decreased expression of cyclin G1 in endometrial carcinoma, which may account for carcinogenesis and development of endometrial carcinomas.

Progesterone receptor-B induction of BIRC3 protects endometrial cancer cells from AP1-59-mediated apoptosis

Progesterone is a growth inhibitory hormone in the endometrium. While progestins can be used for the treatment of well-differentiated endometrial cancers, resistance to progestin therapy occurs for reasons that remain unclear. We have previously demonstrated that progesterone receptors (PR) A and B differentially regulate apoptosis in response to overexpression of the forkhead transcription factor, FOXO1. In this study, we further examined the PR-isoform-dependent cellular response to the AKT pathway. Treatment of PRA and PRB-expressing Ishikawa cells (PRA14, PRB23), with an AKT inhibitor API-59CJ-OMe (API-59) promoted apoptosis in the presence and absence of the ligand, R5020 preferentially in PRA14 cells. Upon PR knockdown using small interfering RNA, an increase in apoptosis was observed in PRB23 cells treated with API-59 with or without R5020 while there was no influence in PRA14 cells. Using an apoptosis-focused real-time PCR array, genes regulated by API-59 and R5020 were identified both common and unique to PRA14 and PRB23 cells. BIRC3 was identified as the only gene regulated by R5020 which occurred only in PRB cells. Knockdown of BIRC3 in PRB23 cells promoted a decrease in cell viability in response to API-59 + R5020. Furthermore, the important role of inhibitors of apoptosis (IAPs) in the PRB23 cells to promote cell survival was demonstrated using an antagonist to IAPs, a second mitochondria-derived activator of caspase (Smac also known as DIABLO) mimetic. Treatment of PRB23 cells with Smac mimetic increased apoptosis in response to API-59 + R5020. In summary, our findings indicate a mechanism by which PRB can promote cell survival in the setting of high AKT activity in endometrial cancer cells.

The effect of progesterone replacement on gene expression in the corpus luteum during induced regression and late luteal phase in the bonnet monkey (Macaca radiata)

BACKGROUND

In higher primates, although LH/CG play a critical role in the control of corpus luteum (CL) function, the direct effects of progesterone (P4) in the maintenance of CL structure and function are unclear. Several experiments were conducted in the bonnet monkey to examine direct effects of P4 on gene expression changes in the CL, during induced luteolysis and the late luteal phase of natural cycles.

METHODS

To identify differentially expressed genes encoding PR, PR binding factors, cofactors and PR downstream signaling target genes, the genome-wide analysis data generated in CL of monkeys after LH/P4 depletion and LH replacement were mined and validated by real-time RT-PCR analysis. Initially, expression of these P4 related genes were determined in CL during different stages of luteal phase. The recently reported model system of induced luteolysis, yet capable of responsive to tropic support, afforded an ideal situation to examine direct effects of P4 on structure and function of CL. For this purpose, P4 was infused via ALZET pumps into monkeys 24 h after LH/P4 depletion to maintain mid luteal phase circulating P4 concentration (P4 replacement). In another experiment, exogenous P4 was supplemented during late luteal phase to mimic early pregnancy.

RESULTS

Based on the published microarray data, 45 genes were identified to be commonly regulated by LH and P4. From these 19 genes belonging to PR signaling were selected to determine their expression in LH/P4 depletion and P4 replacement experiments. These 19 genes when analyzed revealed 8 genes to be directly responsive to P4, whereas the other genes to be regulated by both LH and P4. Progesterone supplementation for 24 h during the late luteal phase also showed changes in expression of 17 out of 19 genes examined.

CONCLUSION

These results taken together suggest that P4 regulates, directly or indirectly, expression of a number of genes involved in the CL structure and function.

Role of progesterone in endometrial cancer

Progesterone is a key hormone in the endometrium that opposes estrogen-driven growth. Insufficient progesterone will result in unopposed estrogen action that could lead to the development of endometrial hyperplasia and adenocarcinoma. Although these endometrial neoplasias can regress in response to progestin treatment, this does not occur in all instances. To understand this resistance to progesterone and to improve on existing hormonal therapies, it is imperative that the molecular mechanisms of progesterone action through its receptor be deciphered in endometrial cancer. This review highlights what is known thus far regarding the efficacy of progestin therapy in the clinic and the role of progesterone in endometrial cancer cell behavior and gene regulation.

Progesterone receptor action in leiomyoma and endometrial cancer

Progesterone is a key hormone in the regulation of uterine function. In the normal physiological context, progesterone is primarily involved in remodeling of the endometrium and maintaining a quiescent myometrium. When pathologies of the uterus develop, specifically, endometrial cancer and uterine leiomyoma, response to progesterone is usually altered. Progesterone acts through mainly two isoforms of the progesterone receptor (PR), PRA and PRB which have been reported to exhibit different transcriptional activities. Studies examining the expression and function of the PRs in the normal endometrium and myometrium as well as in endometrial cancer and uterine leiomyoma are summarized here. The clinical use of progestins and the transcriptional activity of the PR on genes specific to endometrial cancer and leiomyoma are described. An increased understanding of the differential expression of PRs and response to progesterone in these two diseases is critical in order to develop more efficient and targeted therapies.

Inhibition of Tumor Progression and Paraneoplastic Syndrome Development in a Murine Lung Adenocarcinoma by Medroxyprogesterone Acetate and Indomethacin

Mice bearing LP07 lung adenocarcinoma present some characteristics similar to those shown in patients with several malignant diseases. LP07 tumor bearers develop paraneoplastic syndromes such as cachexia, leukocytosis, and hypercalcemia, partly due to a systemic inflammatory response. We analyzed some of the mechanisms involved in the effectiveness of the association of the appetite-stimulant medroxiprogesterone acetate (MPA) and the nonselective cyclooxigenase (COX) inhibitor indomethacin (INDO) in LP07 tumor bearing mice. INDO and INDO plus MPA treatments significantly inhibited tumor growth, which was not inhibited by MPA. The number of lung metastatic nodules was decreased with all treatments, being most effective INDO alone and INDO plus MPA. A significant decrease of plasmatic levels of the matrix metalloproteinases MMP-9 and MMP-2 correlated with these results. Paraneoplastic syndromes, leukocytosis, and cachexia were abolished by all treatments. We determined effects of the treatments on circulating cytokines shown to regulate cachexia and inflammation. Both treatments alone, and INDO plus MPA, reduced circulating IL-6 throughout tumor evolution. A pronounced increase in serum IL-1ss levels was detected in untreated tumor bearers. These levels decreased and were closer to normal serum values when LP07 mice were treated with INDO plus MPA. The combination of a nonsteroidal antiinflammatory drug as INDO and MPA showed to be effective in inhibiting tumor and metastatic growth and diminishing paraneoplastic symptoms and SIR. A variety of specific molecules are implicated as playing a role in cancer-induced cachexia and hematological alterations.

Matrix metalloproteinase induction by relaxin causes cartilage matrix degradation in target synovial joints

Our long-term goal is to understand the mechanisms by which relaxin and estrogen potentially contribute to joint diseases, particularly those afflicting the fibrocartilaginous temporomandibular joint (TMJ). Previously, we showed that relaxin produces a dose-dependent induction of tissue-degrading enzymes of the matrix metalloproteinase (MMP) family, specifically MMP-1 (collagenase-1), MMP-3 (stromelysin-1), MMP-9 (92-kDa gelatinase), and MMP-13 (collagenase-3) in cell isolates and tissue explants from TMJ fibrocartilage. The induction of these MMPs is accompanied by loss of collagen and glycosaminoglycans (GAGs), which was blocked by a pan-MMP inhibitor. We also found the targeted in vivo loss of collagen and GAGs in TMJ discs of ovariectomized rabbits treated with beta-estradiol, relaxin, or both hormones together. Progesterone attenuated the induction of MMPs and matrix loss by relaxin and estrogen. The modulation of matrix composition in TMJ fibrocartilage by these hormones was similar to that observed in the pubic symphysis and differed from that of the knee meniscus. The two target tissues showing the greatest modulation of MMPs and matrix loss, namely, the TMJ disc and pubic symphysis, had similar expression profiles of the estrogen receptors alpha and beta, relaxin-1 receptor (RXFP1, LGR7), and insulin-like peptide 3 receptor (RXFP2, LGR8) and these profiles differed from those in cells from the knee meniscus. These findings suggest a novel model for targeted tissue turnover of cartilage of specific joints through hormone-mediated induction of select MMPs.

Female hormone receptors are differentially expressed in mouse fibrocartilages

OBJECTIVE

Despite the female predilection for joint diseases, and the known effects of female hormones in regulating chondrocyte function, the various female hormone receptor subtypes in joints are not well characterized, and comparisons in receptor profiles between joints and genders are lacking. This investigation characterized and compared the relative levels of estrogen receptors (ER)-alpha and -beta, relaxin receptors LGR7 and LGR8, and progesterone receptor (PR) in the temporomandibular joint (TMJ) disc, knee meniscus (KM) and pubic symphysis fibrocartilages.

METHODS

Fibrocartilaginous cells from 12-week-old mice were maintained in serum-containing alpha-modified Eagle's medium (MEM) until confluence. Total RNA and cell lysates were assayed by RT-PCR, qRT-PCR, immunocytochemistry and Western blots, and joint sections subjected to immunohistochemistry.

RESULTS

All hormone receptors assayed were present in the three joints, but showed substantial differences in expression levels between joints. TMJ cells had higher ER-alpha (>2.8-fold), ER-beta (>2.2-fold), LGR7 (>3-fold) and PR (>1.8-fold), and lower LGR8 (0.5-fold) gene expression levels than KM cells. The ratio of ER-alpha:ER-beta and LGR7:LGR8 was 1.8- and 7.5-fold higher, respectively, in TMJ than in KM cells. The profile of hormone receptors in the TMJ disc was similar to those in the pubic symphysis. Immunochemistry confirmed the differential expression patterns of these receptors in the three tissues. The TMJ cells demonstrated sexual dimorphism in the levels of both ER isoforms, but not of LGR7, LGR8 or PR.

CONCLUSIONS

The findings suggest that these fibrocartilages are putative target tissues for actions of female hormones. The differential expression profiles of the hormone receptors in the three joint fibrocartilages and the sexual dimorphism in ERs in TMJ disc cells are likely to result in varied downstream effects in response to hormones within these fibrocartilaginous tissues.

Effects of doxycycline on serum and endometrial levels of MMP-2, MMP-9 and TIMP-1 in women using a levonorgestrel-releasing subcutaneous implant

BACKGROUND

Endometrial spotting and/or bleeding (ESB) occurs in levonorgestrel subcutaneous implant (LNG SI) users. Matrix metalloproteinases (MMPs) may play a role in ESB.

STUDY DESIGN

Women between 18 and 40 years with regular menstrual cycles had a baseline evaluation followed by LNG SI insertion and randomization to doxycycline (DOX; 20 mg) or placebo (PL) twice a day. MMP-2, MMP-9 and tissue inhibitor of MMP-1 (TIMP-1) in serum and the endometrium were estimated at baseline and at 1, 3 and 6 months after insertion.

RESULTS

LNG increased serum MMP-9, while DOX decreased MMP-9 levels compared to PL after 1 month (p<.05). DOX decreased endometrial MMP-9 at 1 and 6 months compared to baseline and PL (p<.05). DOX increased endometrial TIMP-1 at 6 months compared with baseline and PL (p<.05). MMP-2 levels were unchanged.

CONCLUSION

LNG SI increased serum MMP-9 and TIMP-1 levels, while DOX decreased both serum and endometrial MMP-9 levels.

The activity of medroxyprogesterone acetate, an androgenic ligand, in ovarian cancer cell invasion

OBJECTIVES

An epithelial ovarian cancer cell line constitutively expressing the androgen receptor was created to evaluate the mechanism and effects of androgen receptor activation on epithelial ovarian cancer cell invasion.

METHODS

Immunocytochemistry and Western blot analyses confirmed androgen receptor expression. Boyden chamber invasion assays were performed using cells treated with the androgen receptor ligands medroxyprogesterone acetate or dihydrotestosterone. The matrix metalloproteinases associated with invasion were investigated using zymographic assays.

RESULTS

Androgen receptor-mediated invasion is ligand dependent. While both medroxyprogesterone acetate and dihydrotestosterone signal through androgen receptor, medroxyprogesterone acetate is more effective at stimulating invasion of epithelial ovarian cancer cells. Unlike the wild-type epithelial ovarian cancer cells, this increase in invasion in androgen receptor + epithelial ovarian cancer cells does not seem to be dependent on matrix metalloproteinase 2 or 9 activation.

CONCLUSION

Although classified as a progestin, medroxyprogesterone acetate has significant androgenic activity unique from the pure androgen dihydrotestosterone. Our studies suggest that pharmacologic doses of medroxyprogesterone acetate may actually increase the invasive potential of epithelial ovarian cancer cells.

LPA receptor 2 mediates LPA-induced endometrial cancer invasion

OBJECTIVE

We have previously shown that lysophosphatidic acid (LPA) promotes the ovarian cancer metastatic cascade. In this study, we evaluated the role of LPA on endometrial cancer invasion.

METHODS

Transient mRNA knockdown was accomplished using pre-designed siRNA duplexes against LPA receptor 2 (LPA2) and human matrix metalloproteinase-7 (MMP-7). RT-PCR was used to characterize LPA receptor and MMP-7 expression. Analysis of in vitro invasion was performed with rat-tail collagen type I coated Boyden chambers. Gelatin zymography was used to evaluate the MMP activity in cell culture conditioned media. Cell-cell and cell-matrix attachment was also assessed upon LPA2 knockdown to further illuminate the LPA2 cascade.

RESULTS

LPA increases HEC1A cellular invasion at physiologic concentrations (0.1-1 muM). Of the four principle LPA receptors, LPA2 is predominantly expressed by HEC1A cells. Transient transfection of LPA2 siRNA reduced LPA2 mRNA expression in HEC1A cells by 93% (P<0.01). Silencing LPA2 eliminated the LPA-stimulated increase in invasion (P<0.05) and reduced LPA-induced MMP-7 secretion/activation, without significantly affecting cell-cell or cell-matrix adhesion. Silencing MMP-7 reduced overall invasion but did not eliminate LPA's pro-invasive effect on HEC1A cells, as compared to negative control (P<0.05). Gelatin zymography confirmed that LPA2 and MMP-7 knockdown reduced MMP-7 activation in HEC1A conditioned media.

CONCLUSION

LPA2 mediates LPA-stimulated HEC1A invasion and the subsequent activation of MMP-7.

Myocardial Matrix Remodeling and the Matrix Metalloproteinases: Influence on Cardiac Form and Function

It is now becoming apparent that dynamic changes occur within the interstitium that directly contribute to adverse myocardial remodeling following myocardial infarction (MI), with hypertensive heart disease and with intrinsic myocardial disease such as cardiomyopathy. Furthermore, a family of matrix proteases, the matrix metalloproteinases (MMPs) and the tissue inhibitors of MMPs (TIMPs), has been recognized to play an important role in matrix remodeling in these cardiac disease states. The purpose of this review is fivefold: 1) to examine and redefine the myocardial matrix as a critical and dynamic entity with respect to the remodeling process encountered with MI, hypertension, or cardiomyopathic disease; 2) present the remarkable progress that has been made with respect to MMP/TIMP biology and how it relates to myocardial matrix remodeling; 3) to evaluate critical translational/clinical studies that have provided a cause-effect relationship between alterations in MMP/TIMP regulation and myocardial matrix remodeling; 4) to provide a critical review and analysis of current diagnostic, prognostic, and pharmacological approaches that utilized our basic understanding of MMP/TIMPs in the context of cardiac disease; and 5) most importantly, to dispel the historical belief that the myocardial matrix is a passive structure and supplant this belief that the regulation of matrix protease pathways such as the MMPs and TIMPs will likely yield a new avenue of diagnostic and therapeutic strategies for myocardial remodeling and the progression to heart failure.

Effects of Menstrual Cycle Status and Gender on Human Neutrophil Phenotype

PROBLEM

The effects of gender and fluctuating ovarian hormones on neutrophil phenotype have yet to be characterized.

METHOD OF STUDY

Neutrophils from females at days 7, 14, 21, and 28 of the menstrual cycle were analyzed by flow cytometry for surface receptor, granule protein, and intracellular cytokine expression. Comparisons were made to neutrophils from males isolated at 7-day intervals during 1 month.

RESULTS

Decreased MMP-9 and TNF-alpha expression by neutrophils from females was observed during the periovulatory period. Comparing the genders, cells from females during the periovulatory period expressed less CD11b and CD18 than those from males. CXCR1 surface levels were higher on neutrophils from female donors.

CONCLUSIONS

Neutrophil phenotype varies minimally during the menstrual cycle and between the genders. Our data provide support for a potential anti-inflammatory effect of ovarian hormones on neutrophils.

RETRACTED: Doxycycline alters the expression of matrix metalloproteases in the endometrial cells exposed to ovarian steroids and pro-inflammatory cytokine

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editors following an investigation by the Office of Research Integrity (ORI) at the Department of Health and Human Services. The investigation confirmed that the data presented has been falsified by the last author.

Effects of the components of hormone therapy on matrix metalloproteinases in breast-cancer cells: an in vitro study

A combination of E and progestogens significantly increased matrix metalloproteinase (MMP)-2 in both T47D cells (E(2)-medroxyprogesteroneacetate [MPA] and E(2)-P) and MCF-7 cells (E(2)-MPA, E(2)-P, and equilin-MPA). All combinations resulted in higher MMP-9 levels in MCF-7 cells, but higher MMP-9 levels resulted only with equilin-norethinderone in T47D cells.

A proposed mechanism for progesterone regulation of trophoblast MMP2 transcription independent of classical progesterone response elements on its promoter

Background

Progesterone receptor act as ligand-inducible transcription factor in the respective target cells by binding to specific progesterone response elements in the promoter of the target genes. However, despite the lack of the classical progesterone response elements on matrix-metalloproteinase-2 promoter, progesterone has been shown to decrease the activity of this promoter

Presentation of the hypothesis

It has recently been suggested that in addition to interacting with their classical co-activators and co-repressors, progesterone receptor are capable of binding to several transcription factors. By interacting with other classes of transcription factors, progesterone receptor is capable of transcriptional activation through the transcription factors cognate DNA binding site.

Testing the hypothesis

Exploring transcription factors and transcription binding sites, interacting with the progesterone receptor in modulation of the matrix-metalloproteinase promoter.

Implications of the hypothesis

Identification of additional endogenous progesterone target genes makes it possible to further explore the signaling mechanisms by which the hormone regulates biological actions. Furthermore, the concepts of ligand-driven conformational diversity and selective tissue actions can be exploited in the future for drug development which selectively regulate orphan receptors from the nuclear receptor family.

The role of hormones for the treatment of endometrial hyperplasia and endometrial cancer

PURPOSE OF REVIEW

Hormone therapy has been palliative for advanced/ recurrent endometrial cancer. High remission rates are seen in well-selected stage I, grade 1 endometrial cancer of young women using hormone therapy (usually progestins) as fertility-preserving treatment. Many other hormones, such as gonadotropin-releasing hormone analogs (GnRHa), selective estrogen receptor modulators, aromatase inhibitors, intrauterine progestins, and others are potential modalities. This review updates the recent publications in this area.

RECENT FINDINGS

Two reports investigating different scheduling of tamoxifen and progestins indicated that tamoxifen may be a valuable adjunct to progestin therapy. GnRHa has been used adjunctively to tamoxifen as second-line hormone therapy for fertility sparing after progestin failed. Aromatase inhibitors have shown their potential in treating endometrial cancer and endometrial hyperplasia as single agent or in combination with progestins. Intrauterine progestins seem efficacious in treating endometrial hyperplasia; its applications on endometrial cancer patients, however, have been limited to postmenopausal women with poor surgical risk.

SUMMARY

Translational research based on molecular mechanisms is mandatory to a more appropriate utilization of hormone therapy. The role of dose, scheduling, route of administration of progestins as well as the addition of other hormonal agents should be further explored by well designed randomized controlled trials.

Hormonal influences on cancer progression and prognosis

Cell differentiation, proliferation, apoptosis, and cell motility are induced and regulated by a host of growth factors, vitamins, and hormones. The mode of function of these modifiers of biological response, the signaling pathways that they activate, and the interacting pathways that can influence the biological outcome have been the focus of attention. Especially recognized and discussed in this review is the deregulation of their function, leading to abnormalities in cell proliferation, alteration of intercellular adhesive cohesion, remodeling of the extracellular matrix, and invasive behavior and metastatic deposition that are so characteristic of tumor development and progression, which strongly underscores the concept of molecular progression of cancer constructed on the basis of the relationship between genetic changes and the biological events associated with cancer progression. The molecular changes associated with hormone- and vitamin-driven responses and the deregulation of the expression and function of their target genes seem to correlate with specific biological events linked with cancer invasion and progression, and these findings could lead to the establishment of new markers of progression and to the development of new strategies for patient management. The scope of this work has been restricted by design and is dictated by the field of interest of the author's laboratory, but it is hoped that this field would be regarded adequately to reflect the wide genre of scientific interest in this field of human disease.

Precipitation casting of drug-loaded microporous PCL matrices: Incorporation of progesterone by co-dissolution

Microporous, poly(epsilon-caprolactone) (PCL) matrices were loaded with progesterone by precipitation casting using co-solutions of PCL and progesterone in acetone. Progesterone loadings up to 32% w/w were readily achieved by increasing the drug content of the starting PCL solution. The kinetics of steroid release in PBS at 37 degrees C over 10 days could be described effectively by a diffusional release model although the Korsmeyer-Peppas model indicated the involvement of multiple release phenomena. The diffusion rate constant (D) increased from 8 to 24 microg/mg matrix/day0.5 as the drug loading increased from 3.6 to 12.4% w/w. A total cumulative release of 75%-95% indicates the high efficiency of steroid delivery. Increasing the matrix density from 0.22 to 0.39 g/cm3, by increasing the starting PCL solution concentration, was less effective in changing drug release kinetics. Retention of anti-proliferative activity of released steroid was confirmed using cultures of breast cancer epithelial (MCF-7) cells. Progesterone released from PCL matrices into PBS at 37 degrees C over 14 days retarded the growth of MCF-7 cells by a factor of at least 3.5 compared with progesterone-free controls. These findings recommend further investigation of precipitation-cast PCL matrices for delivery of bioactive molecules such as anti-proliferative agents from implanted, inserted or topical devices.

Difference in progesterone-receptor isoforms ratio between early and late first-trimester human trophoblast is associated with differential cell invasion and matrix metalloproteinase 2 expression

The expression profile of the progesterone-receptor isoforms and progesterone regulation of matrix metalloproteinase 2 (MMP2) were investigated in early and late first-trimester trophoblast cells. Human trophoblast cells were obtained from legal abortions (6-12 wk of gestation). Purity of 95-98% was verified using immunohistochemistry with specific antibodies. Evaluation of cell count was performed with XTT Reagent kit, and invasion was tested using Matrigel invasion assay. Zymography was used to detect proteolytic activity, and Western blot immunoassay was used to study protein concentration. Gene expression of PGRB, PGR, and MMP2 was studied using reverse transcription-polymerase chain reaction with the housekeeping gene GAPDH used for normalization. Promoter activity was determined using luciferase reporter assay. Differential progesterone-receptor profile was documented with the dominance of PGRB in early trophoblast and the dominance of PGRA in late trophoblast. This differential profile is compatible with the inverse effect of progesterone on the two cell populations, decreasing invasion and gelatinase expression in the early first-trimester trophoblast and increasing invasion and gelatinase expression in the late first-trimester trophoblast. A decrease in MMP2 promoter activity in early trophoblast cells exposed to progesterone suggests that MMP2 expression is regulated by progesterone at the transcriptional level as well. Early trophoblast cells transfected with expressing vector for PGR encoding PGRA revealed less MMP2 activity and reversal of its response to progesterone similar to the effect observed in late trophoblast cells.

Gelatinases A and B (MMP-2 and MMP-9) in endometrial cancer—MMP-9 correlates to the grade and the stage

OBJECTIVE

Matrix metalloproteinases (MMPs) have been linked to aggressive behavior in several malignancies. Gelatinases (MMP-2 and MMP-9) in particular are prognostic factors in many adeno- and epithelial cancers. However, no conclusive data exist concerning the role of gelatinases in endometrial cancer.

METHODS

Eighty-eight patients with endometrial cancer, treated between 1988 and 1993 in Umeå University Hospital, were included. MMP-2 and MMP-9 proteins were analyzed immunohistochemically from paraffin-embedded tissues by using specific monoclonal antibodies. The staining results were compared to the clinical data.

RESULTS

Fifty-two percent of the cases were positive for MMP-9 and 72% for MMP-2. The overexpression of the proteins of either MMP-2 or MMP-9 was associated with poor survival. The predictive value of MMP-2 expression was most distinct in stage I cancers. An association was found between the positivity of MMP-2 and MMP-9. Only 3% of the cases were highly positive for both gelatinases and 18% of the cases were negative for both MMPs. Both gelatinases correlated to the histological grade. MMP-9 also correlated to the clinical stage of the disease, whereas MMP-2 did not. There was no apparent association with either depth of invasion, menopausal status, or the age of the patient.

CONCLUSION

MMP-2 and MMP-9 could serve as markers for the clinical behavior of endometrial cancer. They may further be linked to a tendency to cancer relapse. Thus, these gelatinases may turn out to be potentially useful in decision making about the need for an adjuvant treatment.

Overexpressed progesterone receptor form B inhibit invasive activity suppressing matrix metalloproteinases in endometrial carcinoma cells

In this study, we focused on the influence of progesterone and its receptor in invasion and MMPs on endometrial carcinoma cells. The growth of Ishikawa cells, to which an progesterone receptor form B (PR-B) expressing vector was transfected, was inhibited by progesterone as was the inhibition of the expression of cyclin D1. By invasion assay, in conditions with progesterone, the invasiveness of Ishikawa cells was inhibited as well as the expression of (metalloproteinase) MMP-1, -2, -7 and -9 and Ets-1 decreased. These results suggest that activation of PR-B by progesterone results in tumor suppression by inhibiting cell growth and invasiveness via suppression of the expression of MMPs.

Gonadotropin and steroid regulation of matrix metalloproteinases and their endogenous tissue inhibitors in the developed corpus luteum of the rhesus monkey during the menstrual cycle

The factors regulating the dynamic expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in the primate corpus luteum (CL) during the menstrual cycle are unknown. We hypothesized that LH or progesterone (P) regulate interstitial-collagenase (MMP-1), the gelatinases (MMP-2 and -9), TIMP-1, and TIMP-2 in the CL. Hormone ablation/replacement was performed in rhesus monkeys on Days 9-11 of the luteal phase in five treatment groups (n = 4/group): control (no treatment), antide (GnRH antagonist), antide + LH; antide + LH + trilostane (TRL; 3beta-hydroxysteroid dehydrogenase inhibitor), and antide + LH + TRL + R5020 (nonmetabolizable progestin). On Day 12, the CL was removed and the RNA and protein isolated for real-time polymerase chain reaction and immunoassays, respectively. The MMP-1 mRNA increased 20-fold with antide, whereas LH replacement maintained MMP-1 mRNA at control levels. Likewise, TRL increased MMP-1 mRNA 54-fold, and R5020 prevented this effect. Immunodetectable MMP-1 protein also increased with antide or TRL; these increases were abated with LH or R5020. Gelatinase mRNA and/or protein levels increased with antide (e.g., 3-fold, MMP-2 mRNA), and LH replacement reduced protein levels (e.g., 11-fold, MMP-2). The TRL increased MMP-9, but not MMP-2, expression; however, R5020 replacement had no effect on mRNA or protein levels. The LH treatment increased TIMP-1 and -2 mRNA and TIMP-1 protein expression compared to controls and antide groups, whereas R5020 enhanced only immunodetectable TIMP-1. These data strongly suggest that LH suppresses MMP-1 in the primate CL via P and that it also suppresses gelatinases, either at the mRNA (MMP-2) or protein (MMP-2 and -9) levels, perhaps in part via steroids, including P. In contrast, LH promotes TIMP expression, perhaps via steroids, including P.