17,539 research outputs found
Progestins Related to Progesterone and Testosterone Elicit Divergent Human Endometrial Transcriptomes and Biofunctions.
Progestins are widely used for the treatment of gynecologic disorders and alone, or combined with an estrogen, are used as contraceptives. While their potencies, efficacies and side effects vary due to differences in structures, doses and routes of administration, little is known about their effects on the endometrial transcriptome in the presence or absence of estrogen. Herein, we assessed the transcriptome and pathways induced by progesterone (P4) and the three most commonly used synthetic progestins, medroxyprogesterone acetate (MPA), levonorgestrel (LNG), and norethindrone acetate (NETA), on human endometrial stromal fibroblasts (eSF), key players in endometrial physiology and reproductive success. While there were similar transcriptional responses, each progestin induced unique genes and biofunctions, consistent with their structural similarities to progesterone (P4 and MPA) or testosterone (LNG and NETA), involving cellular proliferation, migration and invasion. Addition of estradiol (E2) to each progestin influenced the number of differentially expressed genes and biofunctions in P4 and MPA, while LNG and NETA signatures were more independent of E2. Together, these data suggest different mechanisms of action for different progestins, with progestin-specific altered signatures when combined with E2. Further investigation is warranted for a personalized approach in different gynecologic disorders, for contraception, and minimizing side effects associated with their use
Risk of cancer after assisted reproduction: a review of the available evidences and guidance to fertility counselors
Infertile women requiring ovarian stimulation and assisted reproduction techniques (ART) are faced with difficult issues. The fear that using hormones could increase their risk of cancer is the most significant. One of the main challenges for assessing cancer risk after ART is the difficulty to separate it from the underlying condition of infertility per se. The delay or the inability to achieve a pregnancy is an important risk factor for breast, endometrial and ovarian cancer. We analyzed the current literature on the topic
Immunophenotype of Atypical Polypoid Adenomyoma of the Uterus: Diagnostic Value and Insight on Pathogenesis
Atypical polypoid adenomyoma (APA) is a rare uterine lesion constituted by atypical endometrioid glands, squamous morules, and myofibromatous stroma. We aimed to assess the immunophenotype of the 3 components of APA, with regard to its pathogenesis and its differential diagnosis. A systematic review was performed by searching electronic databases from their inception to January 2019 for immunohistochemical studies of APA. Thirteen studies with 145 APA cases were included. APA glands appeared analogous to atypical endometrial hyperplasia (endometrioid cytokeratins pattern, Ki67≤50%, common PTEN loss, and occasional mismatch repair deficiency); the prominent expression of hormone receptors and nuclear β-catenin suggest that APA may be a precursor of "copy number-low," CTNNB1-mutant endometrial cancers. Morules appeared as a peculiar type of hyperdifferentiation (low KI67, nuclear β-catenin+, CD10+, CDX2+, SATB2+, p63-, and p40-), analogous to morular metaplasia in other lesions and distinguishable immunohistochemically from both conventional squamous metaplasia and solid cancer growth. Stroma immunphenotype (low Ki67, α-smooth-muscle-actin+, h-caldesmon-, CD10-, or weak and patchy) suggested a derivation from a metaplasia of normal endometrial stroma. It was similar to that of nonatypical adenomyoma, and different from adenosarcoma (Ki67 increase and CD10+ in periglandular stroma) and myoinvasive endometrioid carcinoma (h-caldesmon+ in myometrium and periglandular fringe-like CD10 pattern)
Systemic Therapy in Endometrial Cancer: Recent Advances.
Endometrial cancer is a chemosensitive disease. Studies have established a clear benefit of chemotherapy in advanced stages and trials are ongoing to define its role in early stages as well. As more molecular pathways are being elucidated there is increasing role for targeted agents and future looks quite promising. We did an extensive search both online and offline for all the relevant articles including chemotherapy and targeted therapy for endometrial cancer
Consequences of loss of progesterone receptor expression in development of invasive endometrial cancer
PURPOSE: In endometrial cancer, loss of progesterone receptors (PR) is
associated with more advanced disease. This study aimed to investigate the
mechanism of action of progesterone and the loss of its receptors (PRA and
PRB) in development of endometrial cancer. EXPERIMENTAL DESIGN: A
9600-cDNA microarray analysis was performed to study regulation of gene
expression in the human endometrial cancer subcell line Ishikawa PRAB-36
by the progestagen medroxy progesterone acetate (MPA). Five MPA-regulated
genes were selected for additional investigation. Expression of these
genes was studied by Northern blot and by immunohistochemistry in Ishikawa
subcell lines expressing different PR isoforms. Additionally, endometrial
cancer tissue samples were immunohistochemically stained to study the in
vivo protein expression of the selected genes. RESULTS: In the PRAB-36
cell line, MPA was found to regulate the expression of a number of
invasion- and metastasis-related genes. On additional investigation of
five of these genes (CD44, CSPG/Versican, Tenascin-C, Fibronectin-1, and
Integrin-beta 1), it was observed that expression and progesterone
regulation of expression of these genes varied in subcell lines expressing
different PR isoforms. Furthermore, in advanced endometrial cancer, it was
shown that loss of expression of both PR and E-cadherin was associated
with increased expression CD44 and CSPG/Versican. CONCLUSION: The present
study shows that progestagens exert a modulatory effect on the expression
of genes involved in tumor cell invasion. As a consequence, loss of PR
expression in human endometrial cancer may lead to development of a more
invasive phenotype of the respective tumor
Estradiol, Progesterone, and Transforming Growth Factor α Regulate Insulin-Like Growth Factor Binding Protein-3 (IGFBP3) Expression in Mouse Endometrial Cells
Insulin-like growth factor 1 (IGF1) Is Involved in the proliferation of mouse and rat endometrial cells in a paracrine or autocrine manner. Insulin-like growth factor binding protein-3 (IGFBP3) modulates actions of IGFs directly or indirectly. The present study aimed to determine whether IGFBP3 is Involved In the regulation of proliferation of mouse endometrial cells. Mouse endometrial epithelial cells and stromal cells were isolated, and cultured In a serum free medium. IGF1 stimulated DNA synthesis by endometrial epithelial and stromal cells, and IGFBP3 Inhibited IGF1-induced DNA synthesis. Estradiol-17 beta (E2) decreased the Igfbp3 mRNA level in endometrial stromal cells, whereas It Increased the Igf1 mRNA level. Transforming growth factor alpha (TGF alpha) significantly decreased IGFBP3 expression at both the mRNA and secreted protein levels in endometrial stromal cells. Progesterone (134) did not affect the E2-induced down-regulation of Igfbp3 mRNA expression in endometrial stromal cells, although P4 alone increased Igfbp3 mRNA levels. The present findings suggest that in mouse endometrial stromal cells E2 enhances IGF1 action through enhancement of IGF1 synthesis and reduction of IGFBP3 synthesis, and that TGF alpha affects IGF1 actions through modulation of IGFBP3 levels
Estrogen Receptor Signaling in the Endometrium: pathway analysis of agonists and antagonists
Endometrial cancer is the most common gynecological malignancy in Europe and the USA. In the
normal endometrium, growth and differentiation is controlled by the ovarian hormones estrogen
and progesterone. After menopause, the absence of follicle recruitment in the ovary results in a
decline in serum levels of estrogen and progesterone, and consequently results in an
atrophic/inactive state of the endometrium. However, in some women increased levels of
estrogen (either endogenous or exogenous) are present, which will stimulate the endometrium.
This estrogen-induced growth of the endometrium may result in uncontrolled growth, which can
eventually develop into cancer. As in the normal endometrium, progesterone inhibits growth of
endometrial cancer cells and is therefore used in the clinic as adjuvant therapy.
Tamoxifen, a selective estrogen receptor modulator (SERM), is standard adjuvant
therapy for patients with estrogen receptor positive (ER+) breast cancer (estrogen-antagonistic
effect). In the endometrium, however, tamoxifen displays an estrogen-agonistic effect, and use
of tamoxifen is therefore associated with an increased risk for development of endometrial
pathologies, including endometrial cancer.
For the endometrium, but also for many other organs, growth factors and growth factor
receptors play a central role in mediating the effects of steroid hormones. Growth factors like
IGF-1 and EGF mediate estrogen receptor signaling and are therefore also involved in the
regulation of proliferation of the endometrium and endometrial cancer.
The emphasis of this thesis is on the molecular mechanisms of estrogen receptor controlled
proliferation of the human endometrium and subsequent induction of endometrial cancer.
We postulated and addressed the following questions in this thesis:
1. What are the molecular mechanisms underlying estrogen-induced growth stimulation and
progesterone-induced growth inhibition of endometrial cancer cells?
2. Does activation of the ER signaling pathway result in activation of IGF and/or EGF
signaling, and vice versa, does activation of the IGF and EGF signaling pathways result in
activation of ER signaling?
3. Which genes are regulated by estrogen, tamoxifen, raloxifene and the anti-estrogen
ICI182780 in endometrial cancer cells, and do the four ER-ligands regulate similar genes,
in the same cellular processes or pathways?
4. Which genes are regulated in endometrial tissues of tamoxifen-users compared to nonusers,
and can we, based on the generated gene-expression profiles, elucidate which
pathways are activated by tamoxifen during the early changes which may lead to
endometrial cancer formation
Mutations and amplification of oncogenes in endometrial cancer
Alterations in oncogenes are critical steps in the development of endometrial cancer. To investigate the potential clinical relevance of the amplification of the oncogenes c-erbB2, c-myc, and int-2 and the mutation of K-ras in endometrial cancer, 112 tumors were examined using PCR-based fluorescent DNA technology. Amplification of the three oncogenes and the mutation of K-ras were correlated with age, tumor size, lymph node status, metastases, stage, histological types, grade, steroid hormone receptor expression (estrogen receptor, ER; progesterone receptor, PgR), family history of cancer, previous history of cancer or precursor lesions, and previous history of hormone replacement therapy. Oncogene amplification of c-erbB2 was detected in 18.9%, of c-myc in 2.7% and of int-2 in 4.2%, and K-ras mutation in 11.6%. No significant correlations could be detected between amplification of c-erbB2 and any of the other parameters. Mutation of K-ras is associated with positive expression of PgR. This might indicate that mutation and activation of K-ras are involved in the development of hormonal independence in endometrial cancer
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