Human growth hormone and interleukin-6 are upregulated in endometriosis and endometrioid adenocarcinoma

Growth Hormone Action as a Target in Cancer: Significance, Mechanisms, and Possible Therapies

Growth hormone (GH) is a pituitary-derived endocrine hormone required for normal postnatal growth and development. Hypo- or hypersecretion of endocrine GH results in 2 pathologic conditions, namely GH deficiency (GHD) and acromegaly. Additionally, GH is also produced in nonpituitary and tumoral tissues, where it acts rather as a cellular growth factor with an autocrine/paracrine mode of action. An increasingly persuasive and large body of evidence over the last 70 years concurs that GH action is implicit in escalating several cancer-associated events, locally and systemically. This pleiotropy of GH's effects is puzzling, but the association with cancer risk automatically raises a concern for patients with acromegaly and for individuals treated with GH. By careful assessment of the available knowledge on the fundamental concepts of cancer, suggestions from epidemiological and clinical studies, and the evidence from specific reports, in this review we aimed to help clarify the distinction of endocrine vs autocrine/paracrine GH in promoting cancer and to reconcile the discrepancies between experimental and clinical data. Along this discourse, we critically weigh the targetability of GH action in cancer-first by detailing the molecular mechanisms which posit GH as a critical node in tumor circuitry; and second, by enumerating the currently available therapeutic options targeting GH action. On the basis of our discussion, we infer that a targeted intervention on GH action in the appropriate patient population can benefit a sizable subset of current cancer prognoses.

Potential Benefits of Adding Alendronate, Celecoxib, Itraconazole, Ramelteon, and Simvastatin to Endometrial Cancer Treatment: The EC5 Regimen

Metastatic endometrial cancer continues to be a common cause of death as of 2024, even after maximal use of all currently available standard treatments. To address this problem of metastatic cancer generally in 2025, the drug repurposing movement within oncology identifies medicines in common general medical use that have clinical or preclinical experimental data indicating that they interfere with or inhibit a specific growth driving element identified in a given cancer. The drug repurposing movement within oncology also uses data from large scale in vitro screens of thousands of drugs, looking for simple empirical growth inhibition in a given cancer type. This paper outlines the data showing that five drugs from general medical practice meet these evidence criteria for inhibition of endometrial cancer growth, the EC5 regimen. The EC5 regimen uses the osteoporosis treatment drug, alendronate; the analgesic drug, celecoxib; the antifungal drug, itraconazole; the sleep aid, ramelteon; and the cholesterol lowering drug, simvastatin. Side effects seen with these drugs are usually minimal and easily tolerated by patients.

The roles of tight junction protein cingulin in human endometrioid endometrial cancer

The bicellular tight junction molecule cingulin (CGN) binds to microtubules in centrosomes. Furthermore, CGN contributes to the tricellular tight junction (tTJ) proteins lipolysis-stimulated lipoprotein receptor (LSR) and tricellulin (TRIC). CGN as well as LSR decreased during the malignancy of endometrioid endometrial cancer (EEC). Although tTJ protein LSR is involved in the malignancy of some cancers, including EEC, the role of CGN is unknown. In this study, we investigated the roles of CGN with tTJ proteins in human EEC cells by using the CGN-overexpressing EEC cell line Sawano. In 2D cultures, CGN was colocalized with LSR and TRIC at tTJ or at γ-tubulin-positive centrosomes. In immunoprecipitation with CGN antibodies, CGN directly bound to LSR, TRIC, and β-tubulin. Knockdown of CGN by the siRNA decreased the epithelial barrier and enhanced cell proliferation, migration and invasion, as well as knockdown of LSR. In the Sawano cells cocultured with normal human endometrial stromal cells, knockdown of CGN decreased expression of LSR and TRIC via MAPK and AMPK pathways. In 2.5D cultures, knockdown of CGN induced the formation of abnormal cysts and increased the permeability of FD-4 to the lumen. In 2D and 2.5D cultures, treatment with β-estradiol with or without EGF or TGF-β decreased CGN expression and the epithelial permeability barrier and enhanced cell migration, and pretreatment with EW7197+AG1478, U0126 or an anti-IL-6 antibody prevented this. In conclusion, CGN, with tTJ proteins might suppress the malignancy of human EEC and its complex proteins are sensitive to estrogen and growth factors derived from stromal cells.

Approach to the Patient: Case Studies in Pediatric Growth Hormone Deficiency and Their Management

CONTEXT

Pathologies attributed to perturbations of the GH/IGF-I axis are among the most common referrals received by pediatric endocrinologists.

AIM

In this article, distinctive cased-based presentations are used to provide a practical and pragmatic approach to the management of pediatric growth hormone deficiency (GHD).

CASES

We present 4 case vignettes based on actual patients that illustrate (1) congenital GHD, (2) childhood GHD presenting as failure to thrive, (3) childhood GHD presenting in adolescence as growth deceleration, and (4) childhood-onset GHD manifesting as metabolic complications in adolescence. We review patient presentation and a management approach that aims to highlight diagnostic considerations for treatment based on current clinical guidelines, with mention of new therapeutic and diagnostic modalities being used in the field.

CONCLUSION

Pediatric GHD is diverse in etiology and clinical presentation. Timely management has the potential not only to improve growth but can also ameliorate or even mitigate adverse metabolic outcomes, which can be directly attributed to a GH deficient state.

Growth hormone after CNS tumor diagnosis: the fundamentals, fears, facts, and future directions

Growth hormone deficiency (GHD) may occur in pediatric patients with central nervous system (CNS) tumors at initial tumor presentation or later as treatment-related sequelae. While it is well recognized that growth hormone (GH) has beneficial effects on growth and endocrinopathies, there's often hesitancy by clinicians to initiate GH therapy for GHD after CNS tumor diagnosis due to the perceived increased risk of tumor recurrence. The available data is described here and based on this review, there is no evidence of increased risk of tumor recurrence or secondary malignancy in patients treated with GH after CNS tumor diagnosis. Further understanding of tumor biology and presence of downstream GH targets including insulin-like growth factor-1 (IGF-1) and insulin receptor activity is still needed.

Effects of Growth Hormone on Adult Human Gonads: Action on Reproduction and Sexual Function

Growth hormone (GH), which is commonly considered to be a promoter of growth and development, has direct and indirect effects on adult gonads that influence reproduction and sexual function of humans and nonhumans. GH receptors are expressed in adult gonads in some species including humans. For males, GH can improve the sensitivity of gonadotropins, contribute to testicular steroidogenesis, influence spermatogenesis possibly, and regulate erectile function. For females, GH can modulate ovarian steroidogenesis and ovarian angiogenesis, promote the development of ovarian cells, enhance the metabolism and proliferation of endometrial cells, and ameliorate female sexual function. Insulin-like growth factor-1 (IGF-1) is the main mediator of GH. In vivo, a number of the physiological effects of GH are mediated by GH-induced hepatic IGF-1 and local IGF-1. In this review, we highlight the roles of GH and IGF-1 in adult human gonads, clarify potential mechanisms, and explore the efficacy and the risk of GH supplementation in associated deficiency and assisted reproductive technologies. Besides, the effects of excess GH on adult human gonads are discussed as well.

The roles and clinical applications of interleukins in endometrial carcinoma

As a common malignant tumor of the female reproductive system, endometrial carcinoma (EC) seriously endangers women's health with an increasing incidence. The oncogenesis and progression of cancer are closely linked with immune microenvironment, of which interleukins are the important components. In order to illustrate the roles and clinical applications of interleukins in EC, literature of interleukins and EC were reviewed. Based on the present studies, interleukins play crucial roles in the oncogenesis and development of EC via regulating the proliferation, migration, invasion, angiogenesis, apoptosis, pyroptosis and autophagy of EC as well as the immune function against EC. And some of the interleukins seems to have prospective clinical applications in EC, such as evaluating the risk of tumorigenesis, discriminating the malignancy from benign disorders or normal condition, indicating cancer aggressiveness, predicting the prognosis of patients and serving as the novel therapy. However, there is still a long way to go before the clinical applications of interleukins in EC come into reality. Nevertheless, it is certain that the exploration of interleukins will definitely be of great benefit to the screening, diagnosis and treatment of EC in the future.

The role of growth hormone for fertility in women with hypopituitarism

Growth hormone (GH) is an important regulator of the female reproductive system. In vitro and non-human in vivo studies demonstrate a role of GH in steroidogenesis, folliculogenesis, and post-fertilization development. Given its ability to modulate the reproductive system and potentiate the effects of gonadotropins, a beneficial role of GH replacement therapy to optimize fertility has been suggested. Women with hypopituitarism have lower pregnancy and live birth rates. Limited data suggest a role of GH in enhancing fertility management in women with hypopituitarism. GH replacement therapy may be especially relevant in women with hypopituitarism as well as in women considered poor ovarian responders and require assisted reproductive techniques.

Growth hormone in fertility and infertility: Mechanisms of action and clinical applications

Secreted by the anterior pituitary gland, growth hormone (GH) is a peptide that plays a critical role in regulating cell growth, development, and metabolism in multiple targeted tissues. Studies have shown that GH and its functional receptor are also expressed in the female reproductive system, including the ovaries and uterus. The experimental data suggest putative roles for GH and insulin-like growth factor 1 (IGF-1, induced by GH activity) signaling in the direct control of multiple reproductive functions, including activation of primordial follicles, folliculogenesis, ovarian steroidogenesis, oocyte maturation, and embryo implantation. In addition, GH enhances granulosa cell responsiveness to gonadotropin by upregulating the expression of gonadotropin receptors (follicle-stimulating hormone receptor and luteinizing hormone receptor), indicating crosstalk between this ovarian regulator and the endocrine signaling system. Notably, natural gene mutation of GH and the age-related decline in GH levels may have a detrimental effect on female reproductive function, leading to several reproductive pathologies, such as diminished ovarian reserve, poor ovarian response during assisted reproductive technology (ART), and implantation failure. Association studies using clinical samples showed that mature GH peptide is present in human follicular fluid, and the concentration of GH in this fluid is positively correlated with oocyte quality and the subsequent embryo morphology and cleavage rate. Furthermore, the results obtained from animal experiments and human samples indicate that supplementation with GH in the in vitro culture system increases steroid hormone production, prevents cell apoptosis, and enhances oocyte maturation and embryo quality. The uterine endometrium is another GH target site, as GH promotes endometrial receptivity and pregnancy by facilitating the implantation process, and the targeted depletion of GH receptors in mice results in fewer uterine implantation sites. Although still controversial, the administration of GH during ovarian stimulation alleviates age-related decreases in ART efficiency, including the number of oocytes retrieved, fertilization rate, embryo quality, implantation rate, pregnancy rate, and live birth rate, especially in patients with poor ovarian response and recurrent implantation failure.

Dual Characters of GH-IGF1 Signaling Pathways in Radiotherapy and Post-radiotherapy Repair of Cancers

Radiotherapy remains one of the most important cancer treatment modalities. In the course of radiotherapy for tumor treatment, the incidental irradiation of adjacent tissues could not be completely avoided. DNA damage is one of the main factors of cell death caused by ionizing radiation, including single-strand (SSBs) and double-strand breaks (DSBs). The growth hormone-Insulin-like growth factor 1 (GH-IGF1) axis plays numerous roles in various systems by promoting cell proliferation and inhibiting apoptosis, supporting its effects in inducing the development of multiple cancers. Meanwhile, the GH-IGF1 signaling involved in DNA damage response (DDR) and DNA damage repair determines the radio-resistance of cancer cells subjected to radiotherapy and repair of adjacent tissues damaged by radiotherapy. In the present review, we firstly summarized the studies on GH-IGF1 signaling in the development of cancers. Then we discussed the adverse effect of GH-IGF1 signaling in radiotherapy to cancer cells and the favorable impact of GH-IGF1 signaling on radiation damage repair to adjacent tissues after irradiation. This review further summarized recent advances on research into the molecular mechanism of GH-IGF1 signaling pathway in these effects, expecting to specify the dual characters of GH-IGF1 signaling pathways in radiotherapy and post-radiotherapy repair of cancers, subsequently providing theoretical basis of their roles in increasing radiation sensitivity during cancer radiotherapy and repairing damage after radiotherapy.

Peptide Hormone Regulation of DNA Damage Responses

DNA damage response (DDR) and DNA repair pathways determine neoplastic cell transformation and therapeutic responses, as well as the aging process. Altered DDR functioning results in accumulation of unrepaired DNA damage, increased frequency of tumorigenic mutations, and premature aging. Recent evidence suggests that polypeptide hormones play a role in modulating DDR and DNA damage repair, while DNA damage accumulation may also affect hormonal status. We review the available reports elucidating involvement of insulin-like growth factor 1 (IGF1), growth hormone (GH), α-melanocyte stimulating hormone (αMSH), and gonadotropin-releasing hormone (GnRH)/gonadotropins in DDR and DNA repair as well as the current understanding of pathways enabling these actions. We discuss effects of DNA damage pathway mutations, including Fanconi anemia, on endocrine function and consider mechanisms underlying these phenotypes. (Endocrine Reviews 41: 1 - 19, 2020).

Adipocytokines and their relationship to endometrial cancer risk: A systematic review and meta-analysis

OBJECTIVE

To investigate the association between circulating levels of adipocytokines (adiponectin, leptin, tumour necrosis factor alpha (TNFα), interleukin 6 (IL-6)) and growth factors (insulin-like growth factor I (IGF-I) and II (IGF-II)), and the risk of endometrial cancer.

METHODS

Cochrane, CINAHL, Embase, Medline and Web of Science were searched for English-language manuscripts published between January 2000 and August 2018 using the following string of words: cancer and endometrial and (obesity or BMI) and (adiponectin or TNF* or IGF-I or IGF-II or IL-6 or leptin).

RESULTS

Twenty articles were included in this meta-analysis, which corresponded to 18 studies involving 2921 endometrial carcinoma cases and 5302 controls. Fourteen articles reported circulating levels for adiponectin, seven for leptin, three for TNFα, three for IL-6 and one for IGF-I. No article reported values for IGF-II. Patients with circulating adiponectin levels in the highest tertile had decreased endometrial cancer risk compared to women with levels in the lowest tertile, (summary of odds ratio (SOR) 0.51, 95% confidence interval (CI): 0.38-0.69, p < 0.00001). Women with circulating leptin concentrations in the highest tertile had increased endometrial cancer risk compared to women with concentrations in the lowest tertile (SOR 2.19, 95% CI: 1.45-3.30, p = 0.0002). There was no difference in cancer risk between participants with the highest TNFα and IL-6 levels compared to the lowest levels (SOR 1.27, 95% CI: 0.88-1.83, p = 0.20 and SOR 1.20, 95% CI: 0.89-1.63, p = 0.23, respectively).

CONCLUSIONS

Endometrial cancer risk is inversely affected by adiponectin and leptin levels. There appears to be no relationship between TNFα and IL-6 and the overall risk of endometrial cancer.

Inflammatory, oxidative stress and anti-oxidative markers in patients with endometrial carcinoma and diabetes

BACKGROUND

The role of chronic inflammation and oxidative stress in the development of diabetes and cancer has been established. In this study, we aimed to investigate inflammatory and oxidative stress markers in patients with diabetes (DM) and endometrial carcinoma (EC) separately and in combination.

METHODS

In a case-control study design, a total of 88 participants were enrolled including: 37 patients with EC (19 with DM and 18 without DM), 29 with type2 diabetes and 22 healthy controls. Cancer patients were sampled before treatment. Serum oxidative stress markers including: oxidized low density lipoprotein (ox-LDL,) nitric oxide (NO), advanced glycation end-products (AGEs) and advanced oxidation protein products (AOPP), malondialdehyde (MDA); ferric reducing ability of plasma (FRAP), as an antioxidant marker, and inflammatory markers including: Interleukin 6 (IL6), C reactive protein (CRP) and tumor necrosis factor alpha (TNFα) were measured.

RESULTS

Ox-LDL, NO, MDA, AOPP and AGE were increased in all patients either with endometrial carcinoma and/or diabetes compared to healthy controls (p < 0.05). Patients with both EC and DM had higher oxidative markers including: OX-LDL (17.47 ± 0.84 vs. 12.36 ± 0.91), NO (82.27 ± 5.75 vs. 76.34 ± 5.36), MDA (3.3 ± 0.1 vs. 2.75 ± 0.48) and AGE (73.89 ± 5.71 vs. 69.02 ± 3.14) compared to those with EC alone (ρ < 0.05). Levels of FRAP was lower in patients with both diabetes and cancer, cancer alone and diabetes alone compared to healthy controls (p < 0.05). Inflammatory markers, TNFα, IL6 and hs-CRP, were also significantly increased in patients with EC with and without DM compared to controls (ρ < 0.05). However, there were no significant differences between two groups of EC regarding to inflammatory markers (ρ > 0.05). Patients with DM had significantly higher levels of inflammatory markers compared to control group (all ρ < 0.05). In addition, significant subadditive interaction effect between EC and DM regarding levels of oxLDL, NO, AGE, AOPP and FRAP) was observed (p < 0.05).

CONCLUSION

Increased levels of chronic inflammatory and oxidative stress markers were observed in both endometrial carcinoma and diabetes. Additional effect of diabetes in patients with cancer was mediated more significantly via increase in oxidative stress rather than inflammatory markers.

Eutopic endometrium from patients with endometriosis modulates the expression of CD36 and SIRP-α in peritoneal macrophages

Aim

This study aimed to investigate the in vitro alterations of the expression of signal regulatory protein‐α (SIRP‐α) and CD36 in macrophages in the endometriosis condition.

Methods

The expression of SIRP‐α and CD36 was measured in peritoneal macrophages and peripheral blood mononuclear cells of endometriosis patients and control participants. The expressions of SIRP‐α and CD36 were measured in human acute monocytic leukemia (THP‐1) cell‐derived macrophages that were treated with interleukin‐6 (IL‐6)‐induced conditioned medium, eutopic versus normal endometrial homogenate, or lipopolysaccharide in the presence or absence of nuclear factor kappa‐B (NF‐κB) or transforming growth factor (TGF‐β) inhibitors, respectively.

Results

Peritoneal macrophages that were isolated from women with endometriosis exhibited an enhanced expression of SIRP‐α and a decreased expression of CD36 compared to control participants. Women with endometriosis had significantly higher levels of SIRP‐α and CD36 in peripheral circulating mononuclear cells than in control participants. SIRP‐α expression was significantly increased, whereas the CD36 expression was decreased in THP‐1 cell‐derived macrophages after treatment with eutopic endometrial homogenate. Intervention with IL‐6‐induced conditioned medium resulted in the downregulation of SIRP‐α but the upregulation of CD36 in THP‐1 cells. Incubation with the NF‐κBp50 inhibitor decreased the expression of CD36 and SIRP‐α in macrophages that were treated with normal endometrial homogenate, whereas the TGF‐β inhibitor enhanced the CD36 expression of THP‐1 cell‐derived macrophages treated with eutopic endometrial homogenate.

Conclusion

The eutopic endometrium could reduce the phagocytic ability of peritoneal macrophages in women with endometriosis through the modulation of SIRP‐α and CD36 expression. Inhibition of the TGF‐β signal pathway may be a potential therapeutic target for the treatment of endometriosis.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.

Effects of growth hormone on pregnancy rates of patients with thin endometrium

PURPOSE

To investigate whether growth hormone (GH) could improve pregnancy rates of patients with thin endometrium by clinical study and laboratory experiments.

MATERIALS AND METHODS

Ninety-three patients were randomized to either the GH-received group (40) or the routine exogenous administration of estrogens control group (53) for clinical study. The human endometrial carcinoma cell line RL95-2 was used for testing the role of GH with Western blot and real-time PCR by exposure to various concentrations of GH (0.1 nM,1 nM,10 nM,100 nM).

RESULTS

Patients treated with GH had a significantly (P < 0.05) greater endometrium thickness on day 3 (7.87±0.72 vs 6.34±0.86), higher implantation rates (24.4% vs 10.5%) and greater clinical pregnancy rates (42.5% vs 18.9%) compared with the control group. No adverse events were associated with the use of GH. Administration of GH significantly up-regulated the expression of VEGF, ItgB3 and IGF-I expression in RL95-2 cells at both mRNA and protein levels (P < 0.05). AG490, an inhibitor of JAK2, nearly completely inhibited the up-regulative effect of GH through the JAK2-STAT5 pathway, and GH-induced effects could be mediated through autocrine IGF-I together with its hepatic counterpart. IGF-I mRNA was detected in the RL95-2 cells.

CONCLUSION

GH may improve pregnancy outcomes of patients with thin endometrium who undergo frozen embryo transfer by acting on human endometrial cells to promote proliferation and vascularization and to up-regulate receptivity-related molecular expression.

Autocrine hGH stimulates oncogenicity, epithelial-mesenchymal transition and cancer stem cell-like behavior in human colorectal carcinoma

Tumor derived human growth hormone (hGH) has been implicated in cancer development and progression. However, the specific functional role of autocrine/paracrine hGH in colorectal cancer (CRC) remains largely to be determined. Herein, we demonstrated a crucial oncogenic role of autocrine hGH in CRC progression. Elevated hGH expression was detected in CRC compared to normal colorectal tissue, and hGH expression in CRC was positively associated with tumor size and lymph node metastasis. Forced expression of hGH stimulated cell proliferation, survival, oncogenicity and epithelial to mesenchymal transition (EMT) of CRC cells, and promoted xenograft growth and local invasion in vivo. Autocrine hGH expression in CRC cells stimulated the activation of the ERK1/2 pathway, which in turn resulted in increased transcription of the mesenchymal marker FIBRONECTIN 1 and transcriptional repression of the epithelial marker E-CADHERIN. The autocrine hGH-stimulated increase in CRC cell proliferation, cell survival and EMT was abrogated upon ERK1/2 inhibition. Furthermore, autocrine hGH-stimulated CRC cell migration and invasion was dependent on the ERK1/2-mediated increase in FIBRONECTIN 1 expression and decrease in E-CADHERIN expression. Forced expression of hGH also enhanced CSC-like behavior of CRC cells, as characterized by increased colonosphere formation, ALDH-positive population and CSC marker expression. Autocrine hGH-enhanced cancer stem cell (CSC)-like behavior in CRC cells was also observed to be E-CADHERIN-dependent. Thus, autocrine hGH plays a critical role in CRC progression, and inhibition of hGH could be a promising targeted therapeutic approach to limit disease progression in metastatic CRC patients.

Growth Hormone and the Epithelial-to-Mesenchymal Transition

CONTEXT

Previous studies have implicated growth hormone (GH) in the progression of several cancers, including breast, colorectal, and pancreatic. A mechanism by which GH may play this role in cancer is through the induction of the epithelial-to-mesenchymal transition (EMT). During the EMT process, epithelial cells lose their defining phenotypes, causing loss of cellular adhesion and increased cell migration. This review aims to carefully summarize the previous two decades of research that points to GH as an initiator of EMT, in both cancerous and noncancerous tissues.

EVIDENCE ACQUISITION

Sources were collected using PubMed and Google Scholar search engines by using specific GH- and/or EMT-related terms. Identified manuscripts were selected for further analysis based on presentation of GH-induced molecular markers of the EMT process in vivo or in vitro.

EVIDENCE SYNTHESIS

Cellular mechanisms involved in GH-induced EMT are the focus of this review, both in cancerous and noncancerous epithelial cells.

CONCLUSIONS

Our findings suggest that a myriad of molecular mechanisms are induced by GH that cause EMT and may point to potential therapeutic use of GH antagonists or any downregulator of GH action in EMT-related disease.

Clear cell and endometrioid carcinomas: are their differences attributable to distinct cells of origin?

Endometrial epithelium is the presumed tissue of origin for both eutopic and endometriosis-derived clear cell and endometrioid carcinomas. We had previously hypothesized that the morphological, biological and clinical differences between these carcinomas are due to histotype-specific mutations. Although some mutations and genomic landscape features are more likely to be found in one of these histotypes, we were not able to identify a single class of mutations that was exclusively present in one histotype and not the other. This lack of genomic differences led us to an alternative hypothesis that these cancers could arise from distinct cells of origin within endometrial tissue, and that it is the cellular context that accounts for their differences. In a proteomic screen, we identified cystathionine γ-lyase (CTH) as a marker for clear cell carcinoma, as it is expressed at high levels in clear cell carcinomas of the ovary and endometrium. In the current study, we analysed normal Müllerian tissues, and found that CTH is expressed in ciliated cells of endometrium (both eutopic endometrium and endometriosis) and fallopian tubes. We then demonstrated that other ciliated cell markers are expressed in clear cell carcinomas, whereas endometrial secretory cell markers are expressed in endometrioid carcinomas. The same differential staining of secretory and ciliated cells was demonstrable in a three-dimensional organoid culture system, in which stem cells were stimulated to differentiate into an admixture of secretory and ciliated cells. These data suggest that endometrioid carcinomas are derived from cells of the secretory cell lineage, whereas clear cell carcinomas are derived from, or have similarities to, cells of the ciliated cell lineage. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Growth Hormone differentially modulates chemoresistance in human endometrial adenocarcinoma cell lines

Growth Hormone may influence neoplastic development of endometrial epithelium towards endometrial adenocarcinoma, which is one of the most occurring tumors in acromegalic patients. Since chemoresistance often develops in advanced endometrial adenocarcinoma, we investigated whether Growth Hormone might influence the development of chemoresistance to drugs routinely employed in endometrial adenocarcinoma treatment, such as Doxorubicin, Cisplatin, and Paclitaxel. Growth Hormone and Growth Hormone receptor expression was assessed by immunofluorescence in two endometrial adenocarcinoma cell lines, AN3 CA and HEC-1-A cells. Growth Hormone effects were assessed investigating cell viability, caspase3/7 activation, ERK1/2, and protein kinase C delta protein expression. AN3 CA and HEC-1-A cells display Growth Hormone and Growth Hormone receptor. Growth Hormone does not influence cell viability in both cells lines, but significantly reduces caspase 3/7 activation in AN3 CA cells, an effect blocked by a Growth Hormone receptor antagonist. Growth Hormone rescues AN3 CA cells from the inhibitory effects of Doxorubicin and Cisplatin on cell viability, while it has no effect on Paclitaxel. Growth Hormone does not influence the pro-apoptotic effects of Doxorubicin, but is capable of rescuing AN3 CA cells from the pro-apoptotic effects of Cisplatin. On the other hand, Growth Hormone did not influence the effects of Doxorubicin and Paclitaxel on HEC-1A cell viability. The protective action of Growth Hormone towards the effects of Doxorubicin may be mediated by ERK1/2 activation, while the pro-apoptotic effects of Cisplatin may be mediated by protein kinase C delta inhibition. All together our results indicate that Growth Hormone may differentially contribute to endometrial adenocarcinoma chemoresistance. This may provide new insights on novel therapies against endometrial adenocarcinoma chemoresistant aggressive tumors.

Expression of Placental Members of the Human Growth Hormone Gene Family Is Increased in Response to Sequential Inhibition of DNA Methylation and Histone Deacetylation

The genes coding for human (h) chorionic somatomammotropin (CS), hCS-A and hCS-B, and placental growth hormone (GH-V), hGH-V, are located at a single locus on chromosome 17. Efficient expression of these placental genes has been linked to local regulatory (5′ P and 3′ enhancer) sequences and a remote locus control region (LCR), in part, through gene transfer in placental and nonplacental tumor cells. However, low levels of endogenous hCS/GH-V transcripts are reported in the same cells compared with term placenta, suggesting that chromatin structure, or regulatory region accessibility, versus transcription factor availability contributes to the relatively low levels. To assess individual hCS-A, CS-B, and GH-V gene expression in placental and nonplacental tumor cells and the effect of increasing chromatin accessibility by inhibiting DNA methylation and histone deacetylation using 5-aza-2′-deoxycytidine (azadC) and trichostatin A (TSA). Low levels of hCS-A, CS-B, and GH-V were detected in placental and nonplacental tumor cells compared with term placenta. A significant >5-fold increase in activity was seen in placental, but not nonplacental, cells transfected with hybrid hCS promoter luciferase genes containing 3′ enhancer sequences. Pretreatment of placental JEG-3 cells with azadC resulted in a >10-fold increase in hCS-A, CS-B, and GH-V RNA levels with TSA treatment compared with TSA treatment alone. This effect was specific as reversing the treatment regimen did not have the same effect. An assessment of hyperacetylated H3/H4 in JEG-3 cells treated with azadC and TSA versus TSA alone revealed significant increases consistent with a more open chromatin structure, including the hCS 3′ enhancer sequences and LCR. These observations suggest that accessibility of remote and local regulatory regions required for efficient placental hGH/CS expression can be restricted by DNA methylation and histone acetylation status. This includes restricting access of the hCS 3′ enhancer sequences to available placental enhancer transcription factors.

Endometriosis, leiomyoma and adenomyosis: the risk of gynecologic malignancy

The aim of this review article was to evaluate the relationship and the possible etiological mechanisms between endometriosis, leiomyoma (LM) and adenomyosis and gynecological cancers, such as ovarian and endometrial cancer and leiomyosarcoma (LMS). MEDLINE was searched for all articles written in the English literature from July 1966 to May 2013. Reports were collected systematically and all the references were also reviewed. Malignant transformation of gynecologic benign diseases such as endometriosis, adenomyosis and LM to ovarian and endometrial cancer remains unclear. Hormonal factors, inflammation, familial predisposition, genetic alterations, growth factors, diet, altered immune system, environmental factors and oxidative stress may be causative factors in carcinogenesis. Early menarche, low parity, late menopause and infertility have also been implicated in the pathogenesis of these cancers. Ovarian cancers and endometriosis have been shown to have common genetic alterations such as loss of heterozygosity (LOH), PTEN, p53, ARID1A mutations. MicroRNAs have also been implicated in malignant transformation. Inflammation releases proinflammatory cytokines, and activates tumor associated macrophages (TAMS) and nuclear factor kappa b (NF-KB) signaling pathways that promote genetic mutations and carcinogenesis. MED12 mutations in LM and smooth muscle tumors of undetermined malignant potential (STUMP) may contribute to malignant transformation to LMS. A hyperestrogenic state may be shared in common with pathogenesis of adenomyosis, LM and endometrial cancer. However, the effect of these benign gynecologic diseases on endometrial cancer should be studied in detail. This review study indicates that endometriosis, LM, adenomyosis may be associated with increased risk of gynecological cancers such as endometrial and ovarian cancers. The patients who have these gynecological benign diseases should be counseled about the future risks of developing cancer. Further studies are needed to investigate the relationship between STUMPs, LMS and LM and characteristics and outcome endometrial carcinoma in adenomyotic patients.

Inducing malignant transformation of endometriosis in rats by long-term sustaining hyperestrogenemia and type II diabetes

This study aimed to induce malignant transformation of endometriosis in Sprague-Dawley rats by hyperestrogenemia and type II diabetes and evaluate its similarity with human disease in biological features. Rats with surgically induced endometriosis were randomized into two groups: those treated with estradiol (5 mg/kg three times/week after surgery), streptozotocin (25 mg/kg, 1 month after surgery), and high carbohydrate-and-fat feed (Es group); and those treated with placebo saline and standard feed (control group). All rats were randomly killed 2, 4, or 8 months after surgery. The endometriosis lesions and the corresponding eutopic endometria were subjected to morphological evaluation, TUNEL, and immunohistochemical analysis for the expressions of proliferating cell nuclear antigen, phosphatase and tensin homolog, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin proteins. In the Es group, three cases (6.0%) of endometriosis showed atypical hyperplasia accompanied by simple hyperplastic eutopic endometria, and two cases (4.0%) of endometriosis showed endometrioid carcinoma accompanied by atypical hyperplastic eutopic endometria. In the Es group, the activity of organelles and the expressions of proliferating cell nuclear antigen, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin increased, and the level of phosphatase and tensin homolog and TUNEL positivity decreased progressively in the order of endometriosis, atypical endometriosis, and malignant endometriosis. The same tendency was found in the corresponding eutopic endometria. The induced malignant endometriosis showed similarities with human disease in the pathological process and histomorphological and molecular biological features. The method is feasible. The malignant transformations of endometriosis and eutopic endometria may have correlations and similarities, but the former may suffer a higher risk of canceration.

Growth hormone and reproduction: a review of endocrine and autocrine/paracrine interactions

The somatotropic axis, consisting of growth hormone (GH), hepatic insulin-like growth factor I (IGF-I), and assorted releasing factors, regulates growth and body composition. Axiomatically, since optimal body composition enhances reproductive function, general somatic actions of GH modulate reproductive function. A growing body of evidence supports the hypothesis that GH also modulates reproduction directly, exerting both gonadotropin-dependent and gonadotropin-independent actions in both males and females. Moreover, recent studies indicate GH produced within reproductive tissues differs from pituitary GH in terms of secretion and action. Accordingly, GH is increasingly used as a fertility adjunct in males and females, both humans and nonhumans. This review reconsiders reproductive actions of GH in vertebrates in respect to these new conceptual developments.

Chicken oviduct-the target tissue for growth hormone action: effect on cell proliferation and apoptosis and on the gene expression of some oviduct-specific proteins

The aim of this study was to examine the in vivo effect of growth hormone (GH) on cell proliferation and apoptosis and on the gene expression of selected proteins in the chicken oviduct before sexual maturity (first oviposition). Ten-week-old Hy-Line Brown chickens were injected three times a week with 200 μg · kg^-1 body weight of recombinant chicken GH (cGH) until 16 weeks of age. Control hens received 0.9 % NaCl with 0.05 % bovine serum albumin as a vehicle. Treatment with cGH increased (P < 0.05) oviduct weight at 16 weeks of age, i.e. 1–2 weeks before onset of egg laying. The highest number of proliferating (determined by proliferating cell nuclear antigen [PCNA] immunocytochemistry) and apoptotic (determined by TUNEL assay) cells in the oviduct was found in the mucosal epithelium, and the lowest in the stroma. Administration of cGH did not increase (P > 0.05) the number of PCNA-positive cells but it decreased (P < 0.01) the number of TUNEL-positive cells, thus increasing the proliferating-to-apoptotic cell ratio in the oviduct. Gene expression (determined by real-time polymerase chain reaction) of apoptosis-related caspase-2 in the magnum and caspase-3 in the magnum and isthmus and their activity (determined by fluorometric assay) in the magnum were attenuated (P < 0.05) in cGH-treated hens. The gene expression of the magnum-specific ovalbumin and the shell-gland-specific ovocalyxins 32 and 36 was increased (P < 0.05) in cGH-treated chickens. In contrast, the expression of Bcl-2 and of caspases 8 and 9 was not affected by cGH in any of the oviductal segments. The results suggest that GH, via the orchestration of apoptosis and expression of some oviduct-specific proteins, participates in the development and activity of the chicken oviduct prior to the onset of egg laying.

The role of chronic inflammation in obesity-associated cancers

There is a strong relationship between metabolism and immunity, which can become deleterious under conditions of metabolic stress. Obesity, considered a chronic inflammatory disease, is one example of this link. Chronic inflammation is increasingly being recognized as an etiology in several cancers, particularly those of epithelial origin, and therefore a potential link between obesity and cancer. In this review, the connection between the different factors that can lead to the chronic inflammatory state in the obese individual, as well as their effect in tumorigenesis, is addressed. Furthermore, the association between obesity, inflammation, and esophageal, liver, colon, postmenopausal breast, and endometrial cancers is discussed.

Autocrine human GH promotes radioresistance in mammary and endometrial carcinoma cells

Although recent advances in breast cancer treatment regimes have improved patient prognosis, resistance to breast cancer therapies, such as radiotherapy, is still a major clinical challenge. In the current study, we have investigated the role of autocrine human GH (hGH) in resistance to ionising radiation (IR)-based therapy. Cell viability and total cell number assays demonstrated that autocrine hGH promoted cell regrowth in the mammary carcinoma cell lines, MDA-MB-435S and T47D, and the endometrial carcinoma cell line, RL95-2, following treatment with IR. In addition, autocrine hGH enhanced MDA-MB-435S and T47D cell clonogenic survival following radiation exposure. The enhanced clonogenic survival afforded by autocrine hGH was mediated by JAK2 and Src kinases. Investigation into the DNA repair capacity demonstrated that autocrine hGH reduced IR-induced DNA damage in MDA-MB-435S and T47D cells. Functional antagonism of hGH increased RL95-2 sensitivity to IR in cell viability and total cell number assays, reduced clonogenic survival and enhanced the induction of DNA damage. Thus, autocrine hGH reduced sensitivity to treatment with IR in mammary and endometrial carcinoma cell lines in vitro, while functional antagonism of hGH sensitised endometrial carcinoma cells to IR. Functional antagonism of hGH, used in conjunction with radiotherapy, may therefore enhance treatment efficacy and improve the prognosis of patients with breast and endometrial cancer.

The association between endometriosis and ovarian cancer: a review of histological, genetic and molecular alterations

OBJECTIVE

This article represents a review of histologic and genetic findings in endometriosis and describes the mechanisms whereby genetic and non-genetic factors potentially contribute to the neoplastic progression of endometriosis.

METHODS

Literature review of the English language literature based on searching in the MEDLINE (PubMed) database and additional collection of reports by systematically reviewing all references from retrieved papers.

RESULTS

Atypical endometriosis seems to represent a transition from benign endometriosis to carcinoma. Endometriosis is characterized by genetic instability: like neoplasms endometriosis seems to be monoclonal in origin, several studies have documented loss of heterozygosity (LOH) in endometriosis, data suggest that mutation of the tumor suppressor gene PTEN play a part in the malignant transformation of endometriosis, some studies have revealed TP53 mutations in endometriotic lesions, and mutation of ARID1A seems to be an important early event in the malignant transformation of endometriosis to endometrioid and clear cell carcinomas. Heme and iron induced oxidative stress, inflammation, and hyperestrogenism are possible links between endometriosis and cancer.

CONCLUSIONS

The histological and genetic alterations in endometriosis seem to explain why endometriosis can be a precursor of some ovarian cancers, especially clear cell and endometrioid carcinomas. However, the exact molecular mechanisms that may lead to this malignant transformation of endometriosis are not completely understood. More and larger studies are needed to clarify how exactly endometriotic tissue undergoes malignant transformation.

Tumor expression of human growth hormone and human prolactin predict a worse survival outcome in patients with mammary or endometrial carcinoma

CONTEXT

Evidence suggests that human GH (hGH) and human prolactin (hPRL) possess an autocrine or paracrine oncogenic role in mammary and endometrial carcinoma. However, especially for hGH, the prognostic relevance of tumor expression of these hormones is not well defined.

OBJECTIVE

We investigated the potential association of tumor mRNA and protein expression of hGH and hPRL with the clinicopathological features of mammary and endometrial carcinoma. The prognostic relevance of the individual or combined expression of hGH and hPRL in mammary and endometrial carcinoma was also determined.

DESIGN

The expression of hGH and hPRL was analyzed in histopathological samples of mammary and endometrial carcinoma, and the respective normal tissues, by in situ hybridization and immunohistochemistry. Kaplan-Meier and Cox regression analysis was performed to examine the association of tumor hGH and hPRL expression with relapse-free survival and overall survival of patients.

RESULTS

hGH expression was significantly associated with lymph node metastasis, tumor stage, human epidermal growth factor receptor-2 status, and proliferative index in mammary carcinoma and with International Federation of Gynecology and Obstetrics grade, myometrial invasion, and ovarian metastases in endometrial carcinoma. hPRL expression was associated with lymph node metastasis, tumor grade, and tumor stage in mammary carcinoma and with International Federation of Gynecology and Obstetrics stage and myometrial invasion in endometrial carcinoma. Both hGH and hPRL expression, individually and combined, are associated with worse relapse-free survival and overall survival in patients with mammary or endometrial carcinoma.

CONCLUSION

Tumor expression of both hGH or hPRL in mammary or endometrial carcinoma is associated with a large and significant difference in survival outcome for patients with these tumors.

Growth hormone, the insulin-like growth factor axis, insulin and cancer risk

Growth hormone (GH), insulin-like growth factor (IGF)-I and insulin have potent growth-promoting and anabolic actions. Their potential involvement in tumor promotion and progression has been of concern for several decades. The evidence that GH, IGF-I and insulin can promote and contribute to cancer progression comes from various sources, including transgenic and knockout mouse models and animal and human cell lines derived from cancers. Assessments of the GH-IGF axis in healthy individuals followed up to assess cancer incidence provide direct evidence of this risk; raised IGF-I levels in blood are associated with a slightly increased risk of some cancers. Studies of human diseases characterized by excess growth factor secretion or treated with growth factors have produced reassuring data, with no notable increases in de novo cancers in children treated with GH. Although follow-up for the vast majority of these children does not yet extend beyond young adulthood, a slight increase in cancers in those with long-standing excess GH secretion (as seen in patients with acromegaly) and no overall increase in cancer with insulin treatment, have been observed. Nevertheless, long-term surveillance for cancer incidence in all populations exposed to increased levels of GH is vitally important.

Obesity, inflammatory markers, and endometrial cancer risk: a prospective case-control study

Obesity, a major risk factor for endometrial cancer, is a low-grade inflammatory state characterized by elevated concentrations of cytokines and acute phase reactants. The current study had two aims: first to investigate the associations of C-reactive protein (CRP), interleukin 6 (IL6), and IL1 receptor antagonist (IL1Ra) with endometrial cancer risk and second to examine to which extent these markers can influence the association between obesity and endometrial cancer. We conducted a case-control study, nested within the European Prospective Investigation into Cancer and Nutrition, which comprised 305 incident cases of endometrial cancer and 574 matched controls. CRP, IL6, and IL1Ra were measured in prospectively collected blood specimens by immunoassays. Data were analyzed using conditional logistic regression. All statistical tests were two-sided, and P values <0.05 were considered statistically significant. We observed a significant increase in risk of endometrial cancer with elevated levels of CRP (odds ratio (OR) for top versus bottom quartile: 1.58, 95% confidence interval (CI): 1.03-2.41, P(trend)=0.02), IL6 (OR for top versus bottom quartile: 1.66, 95% CI: 1.08-2.54, P(trend)=0.008), and IL1Ra (OR for top versus bottom quartile: 1.82, 95% CI: 1.22-2.73, P(trend)=0.004). After adjustment for body mass index (BMI), the estimates were strongly reduced and became non-significant. The association between BMI and endometrial cancer was also substantially attenuated (∼10-20%) after adjustment for inflammatory markers, even when the effects of C-peptide or estrone had already been taken into account. We provided epidemiological evidence that chronic inflammation might mediate the association between obesity and endometrial cancer and that endometrial carcinogenesis could be promoted by an inflammatory milieu.

Extrapituitary growth hormone

Pituitary somatotrophs secrete growth hormone (GH) into the bloodstream, to act as a hormone at receptor sites in most, if not all, tissues. These endocrine actions of circulating GH are abolished after pituitary ablation or hypophysectomy, indicating its pituitary source. GH gene expression is, however, not confined to the pituitary gland, as it occurs in neural, immune, reproductive, alimentary, and respiratory tissues and in the integumentary, muscular, skeletal, and cardiovascular systems, in which GH may act locally rather than as an endocrine. These actions are likely to be involved in the proliferation and differentiation of cells and tissues prior to the ontogeny of the pituitary gland. They are also likely to complement the endocrine actions of GH and are likely to maintain them after pituitary senescence and the somatopause. Autocrine or paracrine actions of GH are, however, sometimes mediated through different signaling mechanisms to those mediating its endocrine actions and these may promote oncogenesis. Extrapituitary GH may thus be of physiological and pathophysiological significance.

STAT3alpha is oncogenic for endometrial carcinoma cells and mediates the oncogenic effects of autocrine human growth hormone

We herein demonstrate an oncogenic role for signal transducer and activator of transcription (STAT)-3alpha (the full length STAT3 isoform), which also mediates autocrine human GH (hGH)-stimulated oncogenicity, in human endometrial carcinoma (EC) cells. Autocrine hGH stimulated Y705 phosphorylation of STAT3 and STAT3-mediated transcriptional activity in a SRC and Janus-2 Kinase dependent manner in human EC cell lines. Forced expression of a constitutively active variant of STAT3alpha increased proliferation, anchorage-independent, three-dimensional (3D) Matrigel, and xenograft growth and promoted epithelial-mesenchymal transition, migration, and invasion of EC cells. Conversely, the oncogenic capacity of EC cells was significantly impaired by treatment with JSI-124, an inhibitor of STAT3 phosphorylation and activity, small interfering RNA-mediated depletion of STAT3alpha, or a dominant-negative variant of STAT3alpha. Furthermore, the enhanced EC cell oncogenicity stimulated by autocrine hGH, was also abrogated by functional inhibition or small interfering RNA-mediated depletion of STAT3alpha. STAT3alpha may therefore be a common mediator of oncogenic signaling pathways stimulating progression of EC.

Immunomodulation in endometrial cancer

Endometrial cancer is the most frequent gynecological cancer and the fourth most common cancer in women in the developed world. Over the last decade, immunotherapy has been the focus of intense investigation as a form of cancer treatment whereby the treatment initiates a host immune response ultimately eradicating the tumor. It has been suggested that in endometrial cancer and many other forms of cancer, immunosuppression poses a significant obstacle at inducing antitumor immunity by immunotherapy. This review will look at the different studies that have identified immunomodulation of T cells, cytokines and macrophages, and regulation of apoptotic and angiogenic factors in endometrial cancer patients that may contribute to the inefficiency of immunotherapy.

Autocrine human growth hormone stimulates oncogenicity of endometrial carcinoma cells

Recent published data have demonstrated elevated levels of human GH (hGH) in endometriosis and endometrial adenocarcinoma. Herein, we demonstrate that autocrine production of hGH can enhance the in vitro and in vivo oncogenic potential of endometrial carcinoma cells. Forced expression of hGH in endometrial carcinoma cell lines RL95-2 and AN3 resulted in an increased total cell number through enhanced cell cycle progression and decreased apoptotic cell death. In addition, autocrine hGH expression in endometrial carcinoma cells promoted anchorage-independent growth and increased cell migration/invasion in vitro. In a xenograft model of human endometrial carcinoma, autocrine hGH enhanced tumor size and progression. Changes in endometrial carcinoma cell gene expression stimulated by autocrine hGH was consistent with the altered in vitro and in vivo behavior. Functional antagonism of hGH in wild-type RL95-2 cells significantly reduced cell proliferation, cell survival, and anchorage-independent cell growth. These studies demonstrate a functional role for autocrine hGH in the development and progression of endometrial carcinoma and indicate potential therapeutic relevance of hGH antagonism in the treatment of endometrial carcinoma.

Immune growth hormone (GH): localization of GH and GH mRNA in the bursa of Fabricius

Expression of growth hormone (GH) and GH receptor (GHR) genes in the bursa of Fabricius of chickens suggests that it is an autocrine/paracrine site of GH production and action. The cellular localization of GH and GH mRNA within the bursa was the focus of this study. GH mRNA was expressed mainly in the cortex, comprised of lymphocyte progenitor cells, but was lacking in the medulla where lymphocytes mature. In contrast, more GH immunoreactivity (GH-IR) was present in the medulla than in the cortex. In non-stromal tissues, GH-IR and GH mRNA were primarily in lymphocytes, and also in macrophage-like cells and secretory dendritic cells. In stromal tissues, GH mRNA, GH and GHR were expressed in cells near the connective tissue (CT) between follicles and below the outer serosa. In contrast, GH (but not GH mRNA or GHR), was present in cells of the interfollicular epithelium (IFE), the follicle-associated epithelium (FAE) and the interstitial corticoepithelium. This mismatch may reflect dynamic temporal changes in GH translation. Co-expression of GHR-IR, GH-IR, GH mRNA and IgG was found in immature lymphoid cells near the cortex and in IgG-IR CT cells, suggesting an autocrine/paracrine role for bursal GH in B-cell differentiation.

Nuclear factor-kappab (NF-kappaB): an unsuspected major culprit in the pathogenesis of endometriosis that is still at large?

Endometriosis, defined as the ectopic presence of endometrial glandular and stromal cells outside the uterine cavity, is a common benign gynecological disorder with an enigmatic pathogenesis. Many genes and gene products have been reported to be altered in endometriosis, yet some of them may not be major culprits but merely unwitting accomplices or even innocent bystanders. Therefore, the identification and apprehension of major culprits in the pathogenesis of endometriosis are crucial to the understanding of the pathogenesis and would help to develop better therapeutics for endometriosis. Although so far NF-kappaB only has left few traces of incriminating fingerprints, several lines of investigation suggest that NF-kappaB, a pivotal pro-inflammatory transcription factor, could promote and maintain endometriosis. Various inflammatory agents, growth factors, and oxidative stress activate NF-kappaB. NF-kappaB proteins themselves and proteins regulated by them have been linked to cellular transformation, proliferation, apoptosis, angiogenesis, and invasion. Interestingly, all existing and nearly all investigational medications for endometriosis appear to act through suppression of NF-kappaB activation. In endometriotic cells, NF-kappaB appears to be constitutively activated, and suppression of NF-kappaB activity by NF-kappaB inhibitors or proteasome inhibitors suppresses proliferation in vitro. Viewing NF-kappaB as a major culprit, an autoregulatory loop model can be postulated, which is consistent with existing data and, more importantly, can explain several puzzling phenomena that are otherwise difficult to interpret based on prevailing theories. This view has immediate and important implications for novel ways to treat endometriosis. Further research is warranted to precisely delineate the roles of NF-kappaB in the pathogenesis of endometriosis and to indict and convict its aiders and abettors.

The oncogenic potential of growth hormone

A growing body of recent literature indicates that in addition to an essential role in growth and development, growth hormone may also play a more sinister role in oncogenic transformation and neoplastic progression. Here we review the accumulating evidence implicating growth hormone in the development and progression of cancer and describe what is known of the mechanisms utilised by this hormone in neoplastic transformation.