Mullerian Inhibiting Substance inhibits cervical cancer cell growth via a pathway involving p130 and p107

Xanthatin suppresses pancreatic cancer cell growth via the ROS/RBL1 signaling pathway: In vitro and in vivo insights

BACKGROUND

As a malignant digestive system tumor, pancreatic cancer has a high mortality rate. Xanthatin is a sesquiterpene lactone monomer compound purified from the traditional Chinese herb Xanthium strumarium L. It has been reported that Xanthatin exhibits inhibitory effects on various cancer cells in retinoblastoma, glioma, hepatoma, colon cancer, lung cancer, as well as breast cancer. However, in pancreatic cancer cells, only one report exists on the suppression of Prostaglandin E2 synthesis and the induction of caspase 3/7 activation in Xanthatin-treated MIA PaCa-2 cells, while systematic in vitro and in vivo investigations and related mechanisms have yet to be explored.

PURPOSE

This research aims to explore the in vitro and in vivo effects of Xanthatin on pancreatic cancer and its molecular mechanisms.

METHODS

The anticancer effects and mechanisms of Xanthatin on pancreatic cancer cells were assessed through employing cell counting kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, carboxyfluorescein diacetate succinimidyl ester (CFDA SE) cell proliferation assay, colony formation assay, wound healing assay, transwell assay, Annexin V-FITC/propidium iodide (PI) dual staining, Hoechst nuclear staining, Western blot analysis, phosphoproteomics, and reactive oxygen species (ROS) measurement. The in vivo anticancer effects of Xanthatin on pancreatic cancer cells were studied using a nude mouse model.

RESULTS

The present study showed that Xanthatin can prevent the proliferation and metastasis of pancreatic cancer cells and trigger the exposure of phosphatidylserine (PS), chromatin condensation, and caspase activation, thereby inducing apoptosis. Phosphoproteomic analysis indicated that Xanthatin inhibits the phosphorylation of the proliferation-associated protein RBL1, and oxidative stress can lead to RBL1 dephosphorylation. Further investigation revealed that Xanthatin significantly upregulates ROS levels in pancreatic cancer cells, and the antioxidant N-acetylcysteine (NAC) can reverse Xanthatin-induced cell proliferation inhibition and apoptosis. In addition, Xanthatin can suppress pancreatic cancer cell growth in a xenograft nude mouse model with low toxicity to the mice.

CONCLUSION

Xanthatin may inhibit the proliferation of pancreatic cancer cells and trigger apoptosis through the ROS/RBL1 signaling pathway.

The Current Status and Future Perspectives of Chimeric Antigen Receptor-Engineered T Cell Therapy for the Management of Patients with Endometrial Cancer

Endometrial cancer (EC) is a gynecological neoplasm that is increasing in occurrence and mortality rates. Although endometrial cancer in the early stages shows a relatively favorable prognosis, there is an increase in cancer-related mortality rates in the advanced or recurrent endometrial carcinoma population and patients in the metastatic setting. This discrepancy has presented an opportunity for research and development of target therapies in this population. After obtaining promising results with hematologic cancers, chimeric antigen receptor (CAR)-T cell immunotherapy is gaining acceptance as a treatment for solid neoplasms. This treatment platform allows T cells to express tumor-specific CARs on the cell surface, which are administered to the patient to treat neoplastic cells. Given that CAR-T cell therapy has shown potential and clinical benefit compared to other T cell treatment platforms, additional research is required to overcome physiological limitations such as CAR-T cell depletion, immunosuppressive tumor microenvironment, and the lack of specific target molecules. Different approaches and development are ongoing to overcome these complications. This review examines CAR-T cell therapy's current use for endometrial carcinomas. We also discuss the significant adverse effects and limitations of this immunotherapeutic approach. Finally, we consolidate signal-seeking early-phase clinical trials and advancements that have shown promising results, leading to the approval of new immunotherapeutic agents for the disease.

Bone morphogenetic protein signaling is a possible therapeutic target in gynecologic cancer

Bone morphogenetic proteins (BMPs) belong to the transforming growth factor β (TGFβ) superfamily. BMPs play crucial roles in embryogenesis and bone remodeling. Recently, BMP signaling has been found to have diverse effects on different types of tumors. In this review, we summarized the effects of BMP signaling on gynecologic cancer. BMP signaling has tumor-promoting effects on ovarian cancer (OC) and endometrial cancer (EC), whereas it has tumor-suppressing effects on uterine cervical cancer (UCC). Interestingly, EC has frequent gain-of-function mutations in ACVR1, encoding one of the type I BMP receptors, which are also observed in fibrodysplasia ossificans progressiva and diffuse intrinsic pontine glioma. Little is known about the relationship between BMP signaling and other gynecologic cancers. Tumor-promoting effects of BMP signaling in OC and EC are dependent on the promotion of cancer stemness and epithelial-mesenchymal transition (EMT). In accordance, BMP receptor kinase inhibitors suppress the cell growth and migration of OC and EC. Since both cancer stemness and EMT are associated with chemoresistance, BMP signaling activation might also be an important mechanism by which OC and EC patients acquire chemoresistance. Therefore, BMP inhibitors are promising for OC and EC patients even if they become resistant to standard chemotherapy. In contrast, BMP signaling inhibits UCC growth in vitro. However, the in vivo effects of BMP signaling have not been elucidated in UCC. In conclusion, BMP signaling has a variety of functions, depending on the types of gynecologic cancer. Therefore, targeting BMP signaling should improve the treatment of patients with gynecologic cancer.

Mutations in the acetylation hotspots of Rbl2 are associated with increased risk of breast cancer

Retinoblastoma like protein-2 (Rbl2) is functionally regulated by phosphorylation and acetylation. Previously, we demonstrated that lysine K1083 (K1079 in human Rbl2) is a potential target for acetylation but its functional role remains elusive. We investigated alterations in human Rbl2 gene specifically targeting exons 19–22 harbouring acetylatable residues i.e. K1072, K1083 and K1115 through single stranded conformation polymorphism (SSCP) in breast cancer patients. The K1083 was found altered into arginine (R) in 51% of the cases but K1072 and K1115 remained conserved. The ‘K1083R’ mutation impairs the acetylation potential of this motif that may result in functional inactivation of Rbl2. These patients also showed poor survival outcome that highlights prognostic relevance of this residue. NIH3T3 cells expressing glutamine (K1083Q) mutated Rbl2 could not be arrested in G₁ by serum starvation, whereas cells expressing Rbl2 with K1083R showed prolonged G₁ arrest in fluorescence activated cell sorting (FACS) analysis. This suggests that K1083 acetylation is important for G₁/S transition. Further, we performed molecular dynamic simulations (MDS) to analyse kinetics of residue K1083 with Cyc-D1/CDK4. Mutations at K1083 impaired this binding exposing neighbouring residues S1080, P1081, S1082 and R1084, hence enhancing the possibility of accelerated phosphorylation. S1080 has previously been reported as a promising candidate of cell cycle dependent phosphorylation in Rbl2. This highlights significance of mutations in the pocket domain of Rbl2 gene in breast cancer, and also strengthen the supposition that K1083 acetylation is pre-requisite for its phosphorylation.

Anti-Müllerian Hormone in Female Reproduction

Anti-Müllerian hormone (AMH), also called Müllerian inhibiting substance, was shown to be synthesized by the ovary in the 1980s. This article reviews the main findings of the past 20 years on the regulation of the expression of AMH and its specific receptor AMHR2 by granulosa cells, the mechanism of action of AMH, the different roles it plays in the reproductive organs, its clinical utility, and its involvement in the principal pathological conditions affecting women. The findings in respect of regulation tell us that AMH and AMHR2 expression is mainly regulated by bone morphogenetic proteins, gonadotropins, and estrogens. It has now been established that AMH regulates the different steps of folliculogenesis and that it has neuroendocrine effects. On the other hand, the importance of serum AMH as a reliable marker of ovarian reserve and as a useful tool in the prediction of the polycystic ovary syndrome (PCOS) and primary ovarian failure has also been acknowledged. Last but not least, a large body of evidence points to the involvement of AMH in the pathogenesis of PCOS.

Functional profiles of Müllerian inhibiting substance/anti-Müllerian hormone (MIS/AMH) in primarily cultured endometrial cancer cells

Background: Müllerian inhibiting substance/anti-Müllerian hormone (MIS/AMH) inhibits proliferation of MIS/AMH receptor-expressing gynecologic tumors in vivo and in vitro, but the underlying mechanisms have not been fully defined. This study aimed to investigate the expression of MIS/AMH type II receptor (MIS/AMHRII) in endometrial cancer, to identify the mechanism of growth inhibition in MIS/AMH-treated endometrial cancer cells, and to evaluate the clinical significance of MIS/AMH as an effective targeted therapy for MIS/AMH receptor-expressing tumors.

Methods: We used tissue samples from 10 patients with total hysterectomy for endometrial cancer. To identify involved signaling pathways, we performed western blotting on apoptosis-, cell cycle-, Wnt signaling-, and autophagy-related proteins.

Results: MIS/AMHRII was highly expressed on the cell membrane of endometrial cancer tissues and primarily cultured endometrial cancer cells. We also found that MIS/AMH treatment reduced cell viability, induced cell cycle arrest, and increased apoptosis. MIS/AMH treatment induced upregulation of β-catenin-interacting protein (ICAT) and inhibition of the Dvl and Axin complex (IDAX) but downregulation of phospho-c-Jun in the Wnt signaling pathway.

Conclusions: MIS/AMH inhibits the growth of MIS/AMH receptor-expressing endometrial cancer cells through regulation of autophagy, apoptosis, and cell cycle pathways, as well as inhibition of Wnt signaling pathways. These data suggest that MIS/AMH functions as a tumor suppressor and may be an effective therapeutic agent in endometrial cancer.

Translational Physiology of Anti-Müllerian Hormone: Clinical Applications in Female Fertility Preservation and Cancer Treatment

Background

Whilst the ability of AMH to induce the regression of the Müllerian ducts in the male fetus is well appreciated, AMH has additional biological actions in relation to steroid biosynthesis and ovarian follicle dynamics. An understanding of the physiology of AMH illuminates the potential therapeutic utility of AMH to protect the ovarian reserve during chemotherapy and in the treatment of female malignancies. The translation of the biological actions of AMH into clinical applications is an emerging focus of research, with promising preliminary results.

Objective and Rationale

Studies indicate AMH restrains primordial follicle development, thus administration of AMH during chemotherapy may protect the ovarian reserve by preventing the mass activation of primordial follicles. As AMH induces regression of tissues expressing the AMH receptor (AMHRII), administration of AMH may inhibit growth of malignancies expressing AMHR II. This review evaluates the biological actions of AMH in females and appraises human clinical applications.

Search Methods

A comprehensive search of the Medline and EMBASE databases seeking articles related to the physiological functions and therapeutic applications of AMH was conducted in July 2021. The search was limited to studies published in English.

Outcomes

AMH regulates primordial follicle recruitment and moderates sex steroid production through the inhibition of transcription of enzymes in the steroid biosynthetic pathway, primarily aromatase and 17α-hydroxylase/17,20-lyase. Preliminary data indicates that administration of AMH to mice during chemotherapy conveys a degree of protection to the ovarian reserve. Administration of AMH at the time of ovarian tissue grafting has the potential to restrain uncontrolled primordial follicle growth during revascularization. Numerous studies demonstrate AMH induced regression of AMHR II expressing malignancies. As this action occurs via a different mechanism to traditional chemotherapeutic agents, AMH has the capacity to inhibit proliferation of chemo-resistant ovarian cancer cells and cancer stem cells.

Wider Implications

To date, AMH has not been administered to humans. Data identified in this review suggests administration of AMH would be safe and well tolerated. Administration of AMH during chemotherapy may provide a synchronistic benefit to women with an AMHR II expressing malignancy, protecting the ovarian reserve whilst the cancer is treated by dual mechanisms.

Immunotherapy in endometrial cancer: rationale, practice and perspectives

Tumor immunotherapy has attracted more and more attention nowadays, and multiple clinical trials have confirmed its effect in a variety of solid tumors. Immune checkpoint inhibitors (ICIs), cancer vaccines, adoptive cell transfer (ACT), and lymphocyte-promoting cytokines are the main immunotherapy methods. Endometrial cancer (EC) is one of the most frequent tumors in women and the prognosis of recurrent or metastatic EC is poor. Since molecular classification has been applied to EC, immunotherapy for different EC subtypes (especially POLE and MSI-H) has gradually attracted attention. In this review, we focus on the expression and molecular basis of the main biomarkers in the immunotherapy of EC firstly, as well as their clinical application significance and limitations. Blocking tumor immune checkpoints is one of the most effective strategies for cancer treatment in recent years, and has now become the focus in the field of tumor research and treatment. We summarized clinical date of planned and ongoing clinical trials and introduced other common immunotherapy methods in EC, such as cancer vaccine and ACT. Hormone aberrations, metabolic syndrome (MetS) and p53 mutant and that affect the immunotherapy of endometrial cancer will also be discussed in this review.

[The study of interaction of different forms of human recombinant anti-mullerian hormone with a chimeric analogue of the AMH type II]

The homodimeric glycoprotein, anti-mullerian hormone (AMH), described over 70 years ago by A. Jost, is the least studied member of the transforming growth factor beta superfamily. Despite the antitumor activity of AMH discovered at the end of the last century, the creation of effective drugs based on AMH is hindered primarily by the lack of information on the mechanism of various AMH forms interaction with a specific type II receptor (MISRII). Previously, we have shown that not only the full-length activated hormone but also its C-terminal fragment (C-rAMH) could bind to MISRII. In this work, using the surface plasmon resonance technique, we compared the interaction of three forms of recombinant AMH (rAMH) with the MISRII analogue - the chimeric protein MISRII-Fc containing AMH type II receptor and a Fc-fragment of the human IgG1 heavy chain. Comparison of the binding of MISRII-Fc, immobilized on a chip with group specificity for human immunoglobulins, to C-rAMH, to intact rAMH (pro-rAMH), and to rAMH containing one uncleaved monomer (hc-rAMH), showed that the KD of the complexes increased: 1.7 nM, 88 nM and 110 nM, respectively. Thus, we have shown that C-terminal fragment of AMH has the maximum affinity for the recombinant MISRII analogue, which indicates the prospects for the development of drugs based on this hormone derivative.

Anti-Müllerian hormone (AMH) autocrine signaling promotes survival and proliferation of ovarian cancer cells

In ovarian carcinoma, anti-Müllerian hormone (AMH) type II receptor (AMHRII) and the AMH/AMHRII signaling pathway are potential therapeutic targets. Here, AMH dose-dependent effect on signaling and proliferation was analyzed in four ovarian cancer cell lines, including sex cord stromal/granulosa cell tumors and high grade serous adenocarcinomas (COV434-AMHRII, SKOV3-AMHRII, OVCAR8 and KGN). As previously shown, incubation with exogenous AMH at concentrations above the physiological range (12.5-25 nM) decreased cell viability. Conversely, physiological concentrations of endogenous AMH improved cancer cell viability. Partial AMH depletion by siRNAs was sufficient to reduce cell viability in all four cell lines, by 20% (OVCAR8 cells) to 40% (COV434-AMHRII cells). In the presence of AMH concentrations within the physiological range (5 to 15 pM), the newly developed anti-AMH B10 antibody decreased by 25% (OVCAR8) to 50% (KGN) cell viability at concentrations ranging between 3 and 333 nM. At 70 nM, B10 reduced clonogenic survival by 57.5%, 57.1%, 64.7% and 37.5% in COV434-AMHRII, SKOV3-AMHRII, OVCAR8 and KGN cells, respectively. In the four cell lines, B10 reduced AKT phosphorylation, and increased PARP and caspase 3 cleavage. These results were confirmed in ovarian cancer cells isolated from patients' ascites, demonstrating the translational potential of these results. Furthermore, B10 reduced COV434-MISRII tumor growth in vivo and significantly enhanced the median survival time compared with vehicle (69 vs 60 days; p = 0.0173). Our data provide evidence for a novel pro-survival autocrine role of AMH in the context of ovarian cancer, which was targeted therapeutically using an anti-AMH antibody to successfully repress tumor growth.

Anti-Müllerian Hormone Type II Receptor Expression in Endometrial Cancer Tissue

Anti-Müllerian hormone (AMH) is responsible for the Müllerian ducts' regression in male fetuses. In cells of cancers with AMH receptors (AMHRII), AMH induces cell cycle arrest or apoptosis. As AMH occurs naturally and does not exhibit significant side effects while reducing neoplastic cell colonies, it can be considered as a potential therapeutic agent for cancer treatment. The purpose of this study was to assess the AMHRII expression in endometrial cancer (EC) in correlation to various demographic data and clinical conditions. Immunohistochemical analysis was used to assess AMHRII expression in EC tissue samples retrieved from 230 women with pre-cancerous state of endometrium (PCS) and EC. AMHRII was detected in 100% of samples. No statistical difference was observed for AMHRII expression depending on the histopathological type of EC, cancer staging, body mass index, and age, as well as the number of years of menstruation, births and miscarriages, and average and total breastfeeding time. Diabetes mellitus type 2 is the only factor that has an impact on AMHRII expression in EC tissue. Thus, this study supports the idea of theoretical use of AMH in EC treatment because all histopathological types of EC at all stages of advancement present receptors for AMH.

Engineering a bioprosthetic ovary for fertility and hormone restoration

There has been an increase in childhood cancer survivors over the past few decades, and with this, an increased awareness of the co-morbidities of the treatment or disease that affect the survivor's quality-of-life. The increased rate of infertility among this patient group and the desire to have biological children voiced by childhood cancer survivors underscores the urgent need for fertility preservation and development of techniques to restore fertility and gonadal hormone function for this population. The ovarian tissue contains a finite source of female gametes that can be transplanted to restore ovarian function and has resulted in over one hundred reported live births. However, the success of biological offspring per ovarian tissue transplant, the reduced lifespan of these transplants, and the potential for these tissues to contain cancer cells from patients with metastatic diseases supports the need for improved options. One innovation that could improve ovarian transplantation is the development of a bioprosthetic ovary comprised of a 3D printed scaffold with isolated ovarian follicles. A murine bioprosthetic ovary restored ovarian hormones in ovariectomized mice, which also gave birth to healthy offspring. Research is ongoing to create the next iteration of the scaffold that would support ovarian follicles from large animal models and humans with the hopes of translating this technology for patients.

CAR T Cells Targeting MISIIR for the Treatment of Ovarian Cancer and Other Gynecologic Malignancies

The prognosis of patients diagnosed with advanced ovarian or endometrial cancer remains poor, and effective therapeutic strategies are limited. The Müllerian inhibiting substance type 2 receptor (MISIIR) is a transforming growth factor β (TGF-β) receptor family member, overexpressed by most ovarian and endometrial cancers while absent in most normal tissues. Restricted tissue expression, coupled with an understanding that MISIIR ligation transmits apoptotic signals to cancer cells, makes MISIIR an attractive target for tumor-directed therapeutics. However, the development of clinical MISIIR-targeted agents has been challenging. Prompted by the responses achieved in patients with blood malignancies using chimeric antigen receptor (CAR) T cell therapy, we hypothesized that MISIIR targeting may be achieved using a CAR T cell approach. Herein, we describe the development and evaluation of a CAR that targets MISIIR. T cells expressing the MISIIR-specific CAR demonstrated antigen-specific reactivity in vitro and eliminated MISIIR-overexpressing tumors in vivo. MISIIR CAR T cells also recognized a panel of human ovarian and endometrial cancer cell lines, and they lysed a battery of patient-derived tumor specimens in vitro, without mediating cytotoxicity of a panel of normal primary human cells. In conclusion, these results indicate that MISIIR targeting for the treatment of ovarian cancer and other gynecologic malignancies is achievable using CAR technology.

[Mullerian inhibiting substance type II receptor as a potential target for antineoplastic therapy]

The review considers properties of the type II anti-Mullerian hormone receptor (mullerian inhibiting substance receptor type II, MISRII), a transmembrane sensor with its own serine/threonine protein kinase activity, triggering apoptosis of the Mullerian ducts in mammalian embryogenesis and providing formation of the male type reproductive system. According to recent data, MISRII overexpression in the postnatal period is found in cells of a number of ovarian, mammary gland, and prostate tumors, and anti-Mullerian hormone (AMH) has a pro-apoptotic effect on MISRII-positive tumor cells. This fact makes MISRII a potential target for targeted anti-cancer therapy. Treatment based on targeting MISRII seems to be a much more effective alternative to the traditional one and will significantly reduce the drug dose. However, the mechanism of MISRII-AMH interaction is still poorly understood, so the development of new anticancer drugs is complicated. The review analyzes MISRII molecular structure and expression levels in various tissues and cell lines, as well as current understanding of the AMH binding mechanisms and data on the possibility of using MISRII as a target for the action of AMH-based antineoplastic drugs.

Anti-Müllerian Hormone Expression in Endometrial Cancer Tissue

Anti-Müllerian hormone (AMH) is a commonly known factor secreted by Sertoli cells, responsible for regression of the Müllerian ducts in male fetuses. AMH has also other functions in humans. In vivo and in vitro studies have shown that AMH inhibits cell cycle and induces apoptosis in cancers with AMH receptors. The aim of the study was to assess whether the tissue of pre-cancerous states of endometrium (PCS) and various histopathologic types of endometrial cancer (EC) exhibit the presence of AMH. We aimed to investigate whether the potential presence of the protein concerns menopausal women or those regularly menstruating, and whether is related to cancers with a good or a bad prognosis, as well as what other factors may influence AMH expression. The undertaken analysis was carried out on tissues retrieved from 232 women who underwent surgical treatment for PCS and EC. Tissues were prepared for immunohistochemical assessment with the use of a tissue microarrays method. AMH expression was confirmed in 23 patients with well differentiated endometrioid adenocarcinoma (G1), moderately differentiated endometrioid adenocarcinoma (G2), clear cell carcinoma (CCA) and nonatypical hyperplasia. AMH was not found in EC tissues in regularly menstruating women. An appropriately long mean period of breastfeeding in line with a prolonged period of hormonal activity had a positive effect on AMH expression. Our results may suggest that AMH is a factor which protects the organism against cancer, and should be further investigated as a potential prognosis marker and a therapeutic agent.

Müllerian inhibiting substance/anti-Müllerian hormone type II receptor protein and mRNA expression in the healthy and cancerous endometria

Müllerian inhibiting substance/anti-Müllerian hormone (MIS/AMH) is a regulator of the female reproductive system, an indicator of ovarian reserve and a growth inhibitor of Müllerian duct-derived tumors in vivo and in vitro. The objective of the present study was to analyze MIS/AMH type II receptor (MIS/AMHRII) protein and mRNA expression in healthy human endometria compared with patients with endometrial hyperplasia and endometrial cancer, providing a foundation for MIS/AMH as a biological modifier for treatment of endometrial hyperplasia and endometrial cancer. The present study included healthy endometrial tissues (n=20), simple endometrial hyperplasia tissues without atypia (n=17), complex endometrial hyperplasia tissues without atypia (n=24) and endometrial cancer tissues (n=8). The location and variation of MIS/AMHRII protein expression was observed by immunohistochemistry. The expression was graded by two pathologists and was categorized as follows: Negative, weakly positive, moderately positive or strongly positive. Reverse transcription-quantitative polymerase chain reaction was used to quantify MIS/AMHRII mRNA expression. The expression of MIS/AMHRII protein was observed in the cytoplasm of healthy human endometria, endometrial hyperplasia and endometrial cancer cells. The frequency of MIS/AMHRII protein expression was 20.22±10.35% in the proliferative phase of the healthy endometrium and 24.09±11.73% in the secretory phase of the healthy endometrium. However, no differences were observed in the menstrual cycle phases. The frequency was 54.50±16.59% in endometrial hyperplasia without atypia, 55.10±15.87% in endometrial hyperplasia with atypia and 73.88±15.70% in endometrial cancer, indicating that expression was enhanced as the disease progressed from healthy to malignant status. In endometrial hyperplasia, MIS/AMHRII protein expression was significantly associated with histological complexity compared with atypia status. The present study demonstrated that MIS/AMHRII is present in healthy endometria, endometrial hyperplasia and endometrial cancer. The low expression frequency of MIS/AMHRII was not significantly different among normal endometrial tissues, however, the protein expression was elevated in endometrial hyperplasia and endometrial cancer. These findings indicated that the study of bioactive MIS/AMH, as a possible treatment for tumors expressing the MIS/AMH receptor, is essential.

Expression of Müllerian-Inhibiting Substance/Anti-Müllerian Hormone Type II Receptor in the Human Theca Cells

CONTEXT

Müllerian-inhibiting substance/anti-Müllerian hormone (MIS/AMH) is produced in the ovarian granulosa cells, and it is believed to inhibit ovarian folliculogenesis and steroidogenesis in women of reproductive age.

OBJECTIVE

To investigate the expression of MIS/AMH type II receptor (MISRII/AMHRII) that binds MIS/AMH in the ovaries of reproductive-age women; to identify the exact targets of MIS/AMH.

DESIGN

Laboratory study using human ovarian tissue.

SETTING

University hospital.

PATIENTS

Tissue samples from 25 patients who had undergone ovarian surgery.

INTERVENTIONS

The segregation of ovarian granulosa and theca cells by laser microdissection was followed by RT-PCR, analyzing MISRII/AMHRII mRNA expression. Afterward, in situ hybridization and immunohistochemistry were performed to determine the localization of MISRII/AMHRII mRNA and protein expression.

MAIN OUTCOME MEASURES

MISRII/AMHRII mRNA expression by RT-PCR, in situ hybridization, and immunohistochemistry.

RESULTS

MISRII/AMHRII were expressed in granulosa and theca cells of preantral and antral follicles. The granulosa cells showed stronger MISRII/AMHRII expression than theca cells. MISRII/AMHRII mRNA staining of granulosa and theca cells in large antral follicles, early atretic follicles, and corpus luteum waned but were still detected weakly, showing higher expression in theca cells than in granulosa cells. However, MISRII/AMHRII protein in the granulosa layer of the atretic follicle and corpus luteum could not be assessed.

CONCLUSIONS

As MISRII/AMHRII is expressed in both granulosa and theca cells, this indicates that MIS/AMH, produced in the granulosa cells, is active in the theca cells as well. MIS/AMH is most likely actively involved not only in the autocrine and endocrine processes but also in the paracrine processes involving theca cells.

Anti-Müllerian hormone inhibits proliferation and induces apoptosis in epithelial ovarian cancer cells by regulating the cell cycle and decreasing the secretion of stem cell factor

Anti-Müllerian hormone (AMH) has been demonstrated to exhibit an inhibitory effect on the proliferation, invasion, metastasis and drug resistance of ovarian cancer. However, the mechanisms underlying these effects remain unclear. In the present study, 10 µg/ml recombinant human AMH (rhAMH) was administered to human OVCAR3 and OVCAR8 epithelial ovarian cancer (EOC) cell lines. Cell proliferation, apoptosis and cell cycle were analyzed. The level of stem cell factor (SCF) was detected using a reverse transcription-quantitative polymerase chain reaction and an ELISA, respectively. The exogenous addition of rhAMH significantly reduced the proliferation of OVCAR3 and OVCAR8 cell lines compared with the control group (P<0.01). The apoptosis rate in the rhAMH treated group (48 h) significantly increased compared with in the control group (OVCAR3, P=0.035; OVCAR8, P=0.020). The apoptosis rate increased at 72 h but did not exhibit a significant difference when compared with the 48 h group (OVCAR3, P=0.145; OVCAR8, P=0.296). The percentage of cells in the G₁ phase in the rhAMH treated group (48 h) increased but was not significantly different compared with the control group (OVCAR3, P=0.070; OVCAR8, P=0.051). However, there was a significant difference at 72 h compared with the control group (OVCAR3, P=0.016; OVCAR8, P=0.019). At 48 h, the rhAMH-treated group exhibited a statistically significant inhibition of SCF mRNA expression levels (P=0.008), but no significant difference in the protein expression levels (P=0.101) compared with the control, though a significant inhibition was exhibited at 72 h (mRNA expression levels, P=0.005; protein expression levels, P=0.036). The present study revealed that rhAMH may be able to inhibit the proliferation and induce the apoptosis of EOC cells via G₁/S-phase cell cycle arrest and the decreased secretion of SCF.

The expression of Müllerian inhibiting substance/anti-Müllerian hormone type II receptor in myoma and adenomyosis

Objective

We compared the expression levels of Müllerian inhibiting substance (MIS)/anti-Müllerian hormone type II receptor (AMHRII) in uterine myoma and adenomyosis to evaluate the possibility of using MIS/anti-Müllerian hormone (AMH) as a biological regulator or therapeutic agent in patients with uterine leiomyoma and adenomyosis.

Methods

We studied normal uterine myometrium, leiomyoma, endometrial tissue, and adenomyosis from 57 patients who underwent hysterectomy for uterine leiomyoma (22 cases) or adenomyosis (28 cases) and myomectomy for uterine myoma (7 cases). Immunohistochemical staining was used to confirm the MIS/AMHRII protein expression level in each tissue. Reverse transcription-polymerase chain reaction was performed to quantify MIS/AMHRII mRNA expression.

Results

The MIS/AMHRII protein was more strongly expressed in uterine myoma (frequency of MIS/AMHRII expressing cells: 51.95%±13.96%) and adenomyosis (64.65%±4.85%) tissues than that in the normal uterine myometrium (3.15%±1.69%) and endometrium (31.10%±7.19%). In the quantitative analysis of MIS/AMHRII mRNA expression, MIS/AMHRII mRNA expression levels in uterine myoma (mean density: 4.51±0.26) and adenomyosis (6.84±0.20) tissues were higher than that in normal uterine myometrial tissue (0.08±0.09) and endometrial tissue (1.63±0.06).

Conclusion

This study demonstrated that MIS/AMHRII was highly and strongly expressed on uterine myoma and adenomyosis. Our data suggest that MIS/AMH may be evaluated as a biological modulator or therapeutic agent on MIS/AMHRII expressing uterine myoma and adenomyosis.

Potential therapeutic applications of human anti-Müllerian hormone (AMH) analogues in reproductive medicine

Members of the transforming growth factor-beta (TGF-beta) superfamily are key regulators of various physiological processes. Anti-Müllerian hormone (AMH) which is also commonly known as Müllerian-inhibiting substance (MIS) is a member of the TGF-beta superfamily and an important regulator of reproductive organ differentiation and ovarian follicular development. While AMH has been used for diagnostic purposes as a biomarker for over 15 years, new potential therapeutic applications of recombinant human AMH analogues are now emerging as pharmacologic agents in reproductive medicine. Therapeutic uses of AMH in gonadal tissue may provide a unique opportunity to address a broad range of reproductive themes, like contraception, ovulation induction, onset of menopause, and fertility preservation, as well as specific disease conditions, such as polycystic ovarian syndrome (PCOS) and cancers of the reproductive tract. This review explores the most promising therapeutic applications for a novel class of drugs known as AMH analogues with agonist and antagonist functions.

Inhibition of CDK4 sensitizes multidrug resistant ovarian cancer cells to paclitaxel by increasing apoptosiss

PURPOSE

Overexpression of cyclin-dependent kinase (CDK) 4 has been observed in a variety of cancers and has been found to contribute to tumor cell growth and proliferation. However, the effect of inhibition of CDK4 in ovarian cancer is unknown. We investigated the therapeutic effect of the CDK4 inhibitor palbociclib in combination with paclitaxel in ovarian cancer cells.

METHODS

Cell viabilities were determined by MTT assay after exposure to different dosages of palbociclib and/or paclitaxel. Western blot, immunofluorescence, and Calcein AM assays were conducted to determine the mechanisms underlying the cytotoxic effects of palbociclib in combination with paclitaxel. CDK4 siRNA was used to validate the outcome of targeting CDK4 by palbociclib in ovarian cancer cells.

RESULTS

We found that combinations of palbociclib and paclitaxel significantly enhanced drug sensitivity in both Rb-positive (SKOV3TR) and Rb-negative (OVCAR8TR) ovarian cancer-derived cells. When combined with paclitaxel, palbociclib induced apoptosis in both SKOV3TR and OVCAR8TR cells. We also found that palbociclib inhibited the activity of P-glycoprotein (Pgp), and that siRNA-mediated CDK4 knockdown sensitized multidrug resistant (MDR) SKOV3TR and OVCAR8TR cells to paclitaxel.

CONCLUSIONS

Inhibition of CDK4 by palbociclib can enhance paclitaxel sensitivity in both Rb-positive and Rb-negative MDR ovarian cancer cells by increasing apoptosis. CDK4 may serve as a promising target in the treatment of ovarian cancer.

Novel role for anti-Müllerian hormone in the regulation of GnRH neuron excitability and hormone secretion

Anti-Müllerian hormone (AMH) plays crucial roles in sexual differentiation and gonadal functions. However, the possible extragonadal effects of AMH on the hypothalamic–pituitary–gonadal axis remain unexplored. Here we demonstrate that a significant subset of GnRH neurons both in mice and humans express the AMH receptor, and that AMH potently activates the GnRH neuron firing in mice. Combining in vivo and in vitro experiments, we show that AMH increases GnRH-dependent LH pulsatility and secretion, supporting a central action of AMH on GnRH neurons. Increased LH pulsatility is an important pathophysiological feature in many cases of polycystic ovary syndrome (PCOS), the most common cause of female infertility, in which circulating AMH levels are also often elevated. However, the origin of this dysregulation remains unknown. Our findings raise the intriguing hypothesis that AMH-dependent regulation of GnRH release could be involved in the pathophysiology of fertility and could hold therapeutic potential for treating PCOS.

Anti-Müllerian hormone (AMH) plays a role in sexual differentiation and gonadal function, but extra-gonadal effects of AMH are not known. Here Cimino et al. show that AMH activates a subset of gonadotrophin-releasing hormone (GnRH)-releasing neurons, contributing to luteinizing hormone secretion from the pituitary gland.

Anti-Proliferative and Apoptotic Activities of Müllerian Inhibiting Substance Combined with Calcitriol in Ovarian Cancer Cell Lines

PURPOSE

This study aimed to investigate whether Müllerian inhibiting substance (MIS) in combination with calcitriol modulates proliferation and apoptosis of human ovarian cancer (OCa) cell lines (SKOV3, OVCAR3, and OVCA433) and identify the signaling pathway by which MIS mediates apoptosis.

MATERIALS AND METHODS

OCa cell lines were treated with MIS in the absence or presence of calcitriol. Cell viability and proliferation were evaluated using the Cell Counting Kit-8 assay and apoptosis was evaluated by DNA fragmentation assay. Western blot and enzyme-linked immunosorbent assay were used to determine the signaling pathway.

RESULTS

The cells showed specific staining for the MIS type II receptor. Treatment of OCa cells with MIS and calcitriol led to dose- and time-dependent inhibition of cell growth and survival. The combination treatment significantly suppressed cell growth, down-regulated the expression of B-cell lymphoma 2 (Bcl-2), and up-regulated the expressions of Bcl-2 associated X protein, caspase-3, and caspase-9 through the extracellular signal-regulated kinase signaling pathway.

CONCLUSION

These results, coupled with a much-needed decrease in the toxic side effects of currently employed therapeutic agents, provide a strong rationale for testing the therapeutic potential of MIS, alone or in combination with calcitriol, in the treatment of OCa.

The human Müllerian inhibiting substance type II receptor as immunotherapy target for ovarian cancer. Validation using the mAb 12G4

Ovarian cancer has the highest mortality rate among gynecologic malignancies. The monoclonal antibody 12G4 specifically recognizes the human Müllerian inhibiting substance type II receptor (MISRII) that is strongly expressed in human granulosa cell tumors (GCT) and in the majority of human epithelial ovarian cancers (EOC). To determine whether MISRII represents an attractive target for antibody-based tumor therapy, we first confirmed by immunohistochemistry with 12G4 its expression in all tested GCT samples (4/4) and all, but one, EOC human tissue specimens (13/14). We then demonstrated in vitro the internalization of 12G4 in MISRII(high)COV434 cells after binding to MISRII and its ability to increase the apoptosis rate (FACS, DNA fragmentation) in MISRII(high)COV434 (GCT) and MISRII(medium)NIH-OVCAR-3 (EOC) cells that express different levels of MISRII. A standard (51)Cr release assay showed that 12G4 mediates antibody-dependent cell-meditated cytotoxicity. Finally, in vivo assessment of 12G4 anti-tumor effects showed a significant reduction of tumor growth and an increase of the median survival time in mice xenografted with MISRII(high)COV434 or MISRII(medium)NIH-OVCAR-3 cells and treated with 12G4 in comparison to controls treated with an irrelevant antibody. Altogether, our data indicate that MISRII is a new promising target for the control of ovarian GCTs and EOCs. A humanized version of the 12G4 antibody, named 3C23K, is in development for the targeted therapy of MISRII-positive gynecologic cancers.

Transcriptome analysis reveals that Müllerian inhibiting substance regulates signaling pathways that contribute to endometrial carcinogenesis

Müllerian inhibiting substance (MIS) has been shown to inhibit growth of a number of tumors in vitro and/or in vivo, but the downstream pathways which it regulates are not fully understood. In the present study we show that MIS type II receptor was highly expressed in AN3CA cells, a cell line derived from human endometrial cancer cell in which MIS-treatment caused a reduction of cell viability, and induced cellular apoptosis and genes involved cell cycle arrest. To understand the genome-wide effects of MIS on gene regulation, we performed serial gene expression analyses from 0 to 96 h at 24 h intervals after treating AN3CA cells with MIS. Transcriptomic analysis of molecular changes induced by MIS identified 2,688 differentially expressed genes that were significantly up- or down-regulated during the 96 h study period. When the 2,688 differentially expressed genes were mapped to known biological processes, Wnt-, cancer-, proteolysis-, cytoskeleton-, cell cycle-, apoptosis-, and MAPK-signaling pathways emerged as the functions most significantly changed by MIS in AN3CA cells. Furthermore, western blot analysis validated that protein expression of cell cycle inhibitory genes, apoptotic protease activating factor-1 (APAF-1), β-catenin-interacting protein (ICAT), Rb related protein 130 (p130), and inhibitor of disheveled Dvl and Axin complex (IDAX), were gradually increased over the time of the study, whereas downstream cell cycle activating genes, cyclin-dependent kinase 2 (CDK2) and phospho-c-Jun were downregulated in MIS-treated AN3CA cells. These transcriptome analyses support previous observations that MIS functions as a tumor suppressor, potentially by regulating signaling pathways that could contribute to endometrial carcinogenesis, and indicating that MIS should be considered as a potential treatment for endometrial cancer.

Müllerian inhibiting substance/anti-Müllerian hormone: A novel treatment for gynecologic tumors

Müllerian inhibiting substance (MIS), also called anti-Müllerian hormone (AMH), is a member of the transforming growth factor-β super-family of growth and differentiation response modifiers. It is produced in immature Sertoli cells in male embryos and binds to MIS/AMH receptors in primordial Müllerian ducts to cause regression of female reproductive structures that are the precursors to the fallopian tubes, the surface epithelium of the ovaries, the uterus, the cervix, and the upper third of the vagina. Because most gynecologic tumors originate from Müllerian duct-derived tissues, and since MIS/AMH causes regression of the Müllerian duct in male embryos, it is expected to inhibit the growth of gynecologic tumors. Purified recombinant human MIS/AMH causes growth inhibition of epithelial ovarian cancer cells and cell lines in vitro and in vitro via MIS receptor-mediated mechanism. Furthermore, several lines of evidence suggest that MIS/AMH inhibits proliferation in tissues and cell lines of other MIS/AMH receptor-expressing gynecologic tumors such as cervical, endometrial, breast, and in endometriosis as well. These findings indicate that bioactive MIS/AMH recombinant protein should be tested in patients against tumors expressing the MIS/AMH receptor complex, perhaps beginning with ovarian cancer because it has the worst prognosis. The molecular tools to identify MIS/AMH receptor expressing ovarian and other cancers are in place, thus, it is possible to select patients for treatment. An MIS/AMH ELISA exists to follow administered doses of MIS/AMH, as well. Clinical trials await the production of sufficient supplies of qualified recombinant human MIS/AMH for this purpose.

Anti-Müllerian hormone is associated with extrauterine involvement and stage of disease in patients with endometrial cancer

Our aim was to evaluate serum levels of anti-Müllerian hormone (AMH) and also immunohistochemical (IHC) staining properties of AMH receptor type II (AMHRII) in patients with endometrial cancer (EC) and a control group. Preoperatively, serum levels of AMH were assessed and AMHRII expression was evaluated by immunohistochemistry in a benign and malignant group. AMH serum levels of the control group and EC patients were comparable. For EC patients, there was no difference with respect to the AMH levels and tumour stage; grade; histological type; deep myometrial invasion; lymphovascular space invasion or lymph node involvement. However, AMH levels in patients with extrauterine involvement were higher than patients with disease confined to the uterus. EC samples were more likely to be stained positive for AMHRII than benign lesions. Also, as the stage of the lesion worsens, the rate of IHC staining of AMHRII decreases. In conclusion, AMHRII is expressed in normal endometrial cells as well as endometrial cancer cells. AMH levels increase in EC, with extrauterine involvement at least in locally advanced disease. Also AMH expression decreases as the disease is staged-up.

[What's new in 2014 about anti-Müllerian hormone?]

The existence of the anti-Müllerian hormone (AMH) has been postulated by Professor Alfred Jost to explain the regression of the Müllerian ducts during male sexual differentiation. Since then, AMH has been purified, its gene and specific receptor, AMHR-II have been cloned. Further, the signaling pathways were identified and it has been observed that AMH was produced by the granulosa cells of growing follicles. From the 2000s, unexpected roles of AMH have been highlighted, reactivating international research on this hormone. It is now well established that AMH plays a key role in the follicular recruitment and development. Over the past years, serum AMH measurements have been proposed as a marker of the follicular ovarian status, and a predictor of assisted reproductive cycles. AMH is also useful to assess the effectiveness of treatment of some gynecological tumors. This article is a review of the past five years advances on the regulation of the expression of AMH and its specific receptor AMHR-II in female.

Mullerian inhibiting substance expression in papillary thyroid cancer

OBJECTIVE

To examine the expression of Mullerian inhibiting substance (MIS) in papillary thyroid cancer.

MATERIALS AND METHODS

The MIS expression was examined by studying the immunohistochemistry in deparafinized sections prepared from tissue blocks of patients who were diagnosed with papillary thyroid cancer, as given in the pathology archive records (n = 23).

RESULTS

In all the cases studied, 50% (n = 10) showed strong staining and 50% showed moderate staining. The percentage of staining was found to be 94.2 ± 3.1% in strongly stained cases and 92.2 ± 2.1% in moderately stained cases. Normal thyroid tissues neighboring the tumor did not display any staining.

CONCLUSION

The MIS expression can be used as a significant tool in differential diagnosis of papillary thyroid cancer and also to shed light on its etiopathogenesis.

RB1 in cancer: different mechanisms of RB1 inactivation and alterations of pRb pathway in tumorigenesis

Loss of RB1 gene is considered either a causal or an accelerating event in retinoblastoma. A variety of mechanisms inactivates RB1 gene, including intragenic mutations, loss of expression by methylation and chromosomal deletions, with effects which are species-and cell type-specific. RB1 deletion can even lead to aneuploidy thus greatly increasing cancer risk. The RB1gene is part of a larger gene family that includes RBL1 and RBL2, each of the three encoding structurally related proteins indicated as pRb, p107, and p130, respectively. The great interest in these genes and proteins springs from their ability to slow down neoplastic growth. pRb can associate with various proteins by which it can regulate a great number of cellular activities. In particular, its association with the E2F transcription factor family allows the control of the main pRb functions, while the loss of these interactions greatly enhances cancer development. As RB1 gene, also pRb can be functionally inactivated through disparate mechanisms which are often tissue specific and dependent on the scenario of the involved tumor suppressors and oncogenes. The critical role of the context is complicated by the different functions played by the RB proteins and the E2F family members. In this review, we want to emphasize the importance of the mechanisms of RB1/pRb inactivation in inducing cancer cell development. The review is divided in three chapters describing in succession the mechanisms of RB1 inactivation in cancer cells, the alterations of pRb pathway in tumorigenesis and the RB protein and E2F family in cancer.

Mullerian inhibiting substance induces apoptosis of human endometrial stromal cells in endometriosis

CONTEXT

Müllerian inhibiting substance (MIS) is produced in Sertoli cells of fetal testis and causes regression of müllerian ducts in male embryos. MIS also can induce the cell cycle arrest and apoptosis in müllerian duct-derived tumors in vivo and in vitro.

OBJECTIVE

Our objective was to investigate the expression of MIS type II receptor (MISR II) and whether MIS can inhibit the proliferation and induce apoptosis in primary cultures of endometrial stromal cells (ESC) of endometriosis.

DESIGN AND SETTINGS

In vitro experiments were performed in the university research laboratory.

PARTICIPANTS

Tissue samples from 12 patients who had undergone evisceration for ovarian endometrial cysts were included in this study.

INTERVENTIONS AND MAIN OUTCOME MEASURES

The expression of MISR II in ESC was investigated by immunohistochemistry. The cell viability and apoptosis in ESC treated with MIS was measured by methylthiazoletetrazolium assay and annexin V analysis. The expression of regulatory proteins in ESC treated with MIS was shown by Western blotting.

RESULTS

ESC showed specific immunostaining for the MISR II. ESC treated with MIS exhibited 32% growth inhibition (P = 0.0001). The changes in cell cycle distribution after MIS exposure at 72 h demonstrated that S and G(2)M phases were decreased; G(0)G(1) and sub-G(0)G(1) phases were increased. ESC treated with MIS showed 13.72% annexin V-fluorescein isothiocyanate positivity. In the ESCs, which contain defective p16, MIS increased the expression of pocket proteins p107 and p130 and decreased E2F transcription factor 1.

CONCLUSIONS

The results support a central role for MIS in endometriosis. Although the precise mechanism of MIS-mediated inhibition of ESC growth has not been fully defined, these data suggest that MIS has activity against ESC in vitro and may also be an effective targeted therapy for endometriosis.

Expression of Müllerian inhibiting substance type II receptor and antiproliferative effects of MIS on human cervical cancer

This study aimed to analyze expression of Müllerian inhibiting substance type II receptor (MISRII) protein and mRNA in cervical neoplasia, to demonstrate the growth inhibition of cervical cancer cells by administration of highly purified recombinant human Müllerian inhibiting substance (MIS) and, furthermore, to evaluate the clinical significance of MIS as a biological modifier for MIS receptor expressing tumors. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for MISRII mRNA expression, and in situ hybridization and immunohistochemistry were used to observe expression, location of MISRII mRNA and protein, respectively. To demonstrate the effect of MIS on the viability of cervical cancer cells, methyl thiazole tetrazolium (MTT) assay was performed. Flow cytometry was used to evaluate the cell cycle distribution after exposure to MIS in cervical cancer cells, and the annexin-V-FITC staining method was performed to demonstrate apoptosis by MIS in cervical cancer cells. Expression of MISRII protein and mRNA were observed in all normal cervical and cervical carcinoma tissues. There was no significant difference in expression of MISRII protein and MISRII mRNA between normal cervical and cervical carcinoma tissues. MTT assay showed negative correlation between MIS exposure time and the viability of cervical cells (P=0.008). The changes in cell cycle distribution after MIS exposure suggest that MIS plays an important role in inducing cellular apoptosis by causing arrest at the G1 phase and increasing cells at sub-G0G1 phase. Annexin-V-FITC staining methods showed that cellular apoptosis was, respectively, 10.44 and 12.89% after 24 and 48 h of MIS exposure in cervical carcinoma cells. There was a negative correlation between cellular survival and MIS exposure time. This study demonstrates that MISRII is present on normal cervical and cervical carcinoma tissues, and MIS shows receptor-mediated antiproliferative effect on cervical cells in vitro. These data suggest that MIS may be used as a biological modifier or therapeutic modulator on MISRII-expressing tumors in the future.

Essential role of gastric gland mucin in preventing gastric cancer in mice

Gastric gland mucin secreted from the lower portion of the gastric mucosa contains unique O-linked oligosaccharides (O-glycans) having terminal α1,4-linked N-acetylglucosamine residues (αGlcNAc). Previously, we identified human α1,4-N-acetylglucosaminyltransferase (α4GnT), which is responsible for the O-glycan biosynthesis and characterized αGlcNAc function in suppressing Helicobacter pylori in vitro. In the present study, we engineered A4gnt(-/-) mice to better understand its role in vivo. A4gnt(-/-) mice showed complete lack of αGlcNAc expression in gastric gland mucin. Surprisingly, all the mutant mice developed gastric adenocarcinoma through a hyperplasia-dysplasia-carcinoma sequence in the absence of H. pylori infection. Microarray and quantitative RT-PCR analysis revealed upregulation of genes encoding inflammatory chemokine ligands, proinflammatory cytokines, and growth factors, such as Ccl2, Il-11, and Hgf in the gastric mucosa of A4gnt(-/-) mice. Further supporting an important role for this O-glycan in cancer progression, we also observed significantly reduced αGlcNAc in human gastric adenocarcinoma and adenoma. Our results demonstrate that the absence of αGlcNAc triggers gastric tumorigenesis through inflammation-associated pathways in vivo. Thus, αGlcNAc-terminated gastric mucin plays dual roles in preventing gastric cancer by inhibiting H. pylori infection and also suppressing tumor-promoting inflammation.

Identification of characteristic molecular signature of Müllerian inhibiting substance in human HPV-related cervical cancer cells

Müllerian inhibiting substance (MIS), also known as anti-Müllerian hormone (AMH), is a member of the transforming growth factor-β (TGF-β) superfamily that plays an important role in the mesenchymal-epithelial interaction, cell growth and proliferation, extracellular matrix production and tissue remodeling. Previously, we demonstrated that MIS suppressed ovarian cancer cell growth and suggested large-scale genetic elements that could be responsible for anti-neoplastic effects of MIS on ovarian cancer cells. In this study, we demonstrated the expression of MIS type II receptor (MISRII) in the human papillomavirus (HPV)-16-related cervical cancer cell lines CaSki and SiHa, and a non-HPV-related cervical cancer cell line, C33A. We also showed that MIS inhibited growth of cervical cancer cells, and induced cellular apoptosis of C33A. In addition, we identified a characteristic molecular signature of MIS in CaSki cells by using whole genome expression analysis. Of the 1,690 genes that showed significant expression changes by MIS, 21 genes were related to cell cycle; 13 genes to apoptosis; and 52 genes to the cancer pathway. On performing a search for cell cycle pathways in the KEGG pathway database, several gene expressions at the G1/S checkpoint were found. In particular, the expression of p16 and p107 increased and that of E2F2 and E2F3 decreased at an early stage, whereas the expression of E2F4 and E2F5 decreased at a later stage after MIS treatment. These data suggest that MIS produces activity against HPV16-related cervical cancers in vitro, and MIS may also be an effective targeted therapy for HPV16-related cervical cancer. Genetic data obtained here could be useful in determining the treatment strategy of MISR-expressing cervical tumors in the future.

Müllerian inhibiting substance/anti-Müllerian hormone: a potential therapeutic agent for human ovarian and other cancers

According to the 2008 American Cancer Society statistics, cancer remains the second leading cause of death in American today. Early detection, innovative surgery, new drugs and increased public education regarding avoidable risk factors, such as smoking, have had significant impact on the incidence and survival rates of many cancers, while overall death rates from all cancers have declined a modest 5% over the past 50 years. Ovarian cancer statistics, however, have not been as encouraging. Despite recent advances in the management of this disease, 5-year survival has not improved, and the search continues for rationally designed new treatments. Müllerian Inhibiting Substance is a strong candidate because it addresses many of the deficiencies of existing treatments. Namely, Müllerian Inhibiting Substance has little demonstrated toxicity, it complements the activity of known anticancer drugs, it is highly specific against cancers expressing its receptor and it inhibits the proliferation of drug-resistant tumors.

Development of an efficiently cleaved, bioactive, highly pure FLAG-tagged recombinant human Mullerian Inhibiting Substance

Mullerian Inhibiting Substance (MIS), a member of the TGF-beta family, causes regression of the Mullerian duct in male embryos, after binding to Mullerian Inhibiting Substance Receptor II (MISRII). It has also been extensively demonstrated that it can inhibit proliferation of various cancer cell lines such as ovarian, prostate, and breast cancer in vitro and in vivo. Hence, the availability of a recombinant, epitope tagged, bioactive MIS is important for the selection of patients for treatment and for probing novel molecular targets for MIS in various tissues. To this end, we have expressed a recombinant, internally FLAG-tagged form of hMIS with the tag (DYKDDDDK) immediately after the cleavage site (427-428) of MIS at the C-terminus with a modified dibasic cleavage motif sequence. We show that this construct results in a highly pure, endogenously processed (cleaved) FLAG MIS, that causes complete regression of the Mullerian Duct in an organ culture assay. In addition, purified FLAG MIS was able to bind and affinity purify both transfected and endogenous MIS type II receptor. The availability of this fully functional, epitope tagged form of MIS should facilitate scale-up for preclinical and clinical use and should also be used for the study of MIS binding proteins and for tracking in pharmacokinetic studies.

Anti-Mullerian hormone (AMH): what do we still need to know?

In the ovary, Anti-Müllerian hormone (AMH) is produced by the granulosa cells of early developing follicles and inhibits the transition from the primordial to the primary follicular stage. AMH levels can be measured in serum and have been shown to be proportional to the number of small antral follicles. In women serum AMH levels decrease with age and are undetectable in the post-menopausal period. In patients with premature ovarian failure AMH is undetectable or greatly reduced depending of the number of antral follicles in the ovaries. In contrast, AMH levels have been shown to be increased in women with polycystic ovary syndrome (PCOS). AMH levels appear to represent the quantity of the ovarian follicle pool and may become a useful marker of ovarian reserve. AMH measurement could also be useful in the prediction of the extremes of ovarian response to gonadotrophin stimulation for in vitro fertilization, namely poor- and hyper-response. Although AMH has the potential to increase our understanding of ovarian pathophysiology, and to guide clinical management in a broad range of conditions, a number of important questions relating to both the basic physiology of AMH and its clinical implications need to be answered.

Interaction of the vitamin D receptor with a vitamin D response element in the Mullerian-inhibiting substance (MIS) promoter: regulation of MIS expression by calcitriol in prostate cancer cells

Calcitriol (1,25-dihydroxyvitamin D(3)) inhibits the growth of a variety of cancer cells including human prostate cancer. Müllerian-inhibiting substance (MIS) also exhibits antiproliferative and proapoptotic actions on multiple cancer cells including human prostate cancer. In this study, we investigated whether calcitriol regulated MIS expression in prostate cancer, an action that might contribute to its antiproliferative activity. We identified a 15-bp sequence, GGGTGAgcaGGGACA, in the MIS promoter that was highly similar to direct repeat 3-type vitamin D response elements (VDREs). The human MIS promoter containing the putative VDRE was cloned into a luciferase reporter vector. In HeLa cells transfected with the vitamin D receptor (VDR), MIS promoter activity was stimulated by calcitriol. Coexpression of steroidogenic factor 1, a key regulator of MIS, increased basal MIS promoter activity that was further stimulated by calcitriol. Mutation or deletion of the VDRE reduced calcitriol-induced transactivation. In addition, the MIS VDRE conferred calcitriol responsiveness to a heterologous promoter. In gel shift assays, VDR and retinoid X receptor bound to the MIS VDRE and the binding was increased by calcitriol. Chromatin immunoprecipitation assays showed that VDR and retinoid X receptor were present on the MIS promoter in prostate cancer cells. In conclusion, we demonstrated that MIS is a target of calcitriol action. MIS is up-regulated by calcitriol via a functional VDRE that binds the VDR. Up-regulation of MIS by calcitriol may be an important component of the antiproliferative actions of calcitriol in some cancers.

Localization of Mullerian inhibiting substance receptors in various human cancer cell lines

Recombinant human MIS (rhMIS) produced in transfected Chinese hamster ovary cells has been purified by immunoaffinity chromatography. In the absence of reducing agents, 140 kD homodimer and several oligomers with molecular masses from 280 to 1000 kD are present. Homodimer, tetramer, and higher-molecular-weight rhMIS fractions reduced survival of tumor cells. For these experiments, FITC-labeled rhMIS was used for binding and endocytosis studies by flow cytometry. Flow cytometry performed on MIS-sensitive cancer cell lines demonstrated specific binding of rhMIS. The majority of rhMIS receptors have cytosolic localization. Thus, the level of MIS receptors on the cell membrane was proportional to the content of MIS-binding proteins in the whole cell and defines a level of receptor-mediated endocytosis. The immunopurified rhMIS caused significant growth inhibition of ovarian and prostate adenocarcinoma and melanoma human cell lines in inhibition assays.

c-Jun N-terminal kinase inhibitor II (SP600125) activates Mullerian inhibiting substance type II receptor-mediated signal transduction

Müllerian inhibiting substance (MIS), the hormone required for Müllerian duct regression in fetal males, is also expressed in both adult males and females, but its physiological role in these settings is not clear. The expression of the MIS type II receptor (MISRII) in ovarian cancer cells and the ability of MIS to inhibit proliferation of these cells suggest that MIS might be a promising therapeutic for recurrent ovarian cancer. Using an MISRII-dependent activity assay in a small-molecule screen for MIS-mimetic compounds, we have identified the c-Jun N-terminal kinase inhibitor SP600125 as an activator of the MIS signal transduction pathway. SP600125 increased the activity of a bone morphogenetic protein-responsive reporter gene in a dose-dependent manner and exerted a synergistic effect when used in combination with MIS. This effect was specific for the MISRII and was not seen with other receptors of the TGFbeta family. Moreover, treatment of mouse ovarian cancer cells with a combination of SP600125 and paclitaxel, an established chemotherapeutic agent used in the treatment of ovarian cancer, or with MIS enabled inhibition of cell proliferation at a lower dose than with each treatment alone. These results offer a strong rationale for testing the therapeutic potential of SP600125, alone or in combination with already established drugs, in the treatment of recurrent ovarian cancer with a much-needed decrease in the toxic side effects of currently employed therapeutic agents.

Mullerian Inhibiting Substance is an ovarian growth factor of emerging clinical significance

OBJECTIVE

To examine Mullerian Inhibiting Substance (MIS) as an emerging diagnostic marker of ovarian function.

DESIGN

Medline review of published studies pertaining to the role of MIS in assessing ovarian aging, predicting response to ovulation induction in preparation for in vitro fertilization, assessing risk of developing ovarian hyperstimulation (OHSS) before ovulation induction, and diagnosis of polycystic ovarian disease (PCOS).

RESULT(S)

The majority of published studies to date support a role for MIS as a marker of ovarian reserve. Specific cut-off values are dependent upon the particular assay used. Mullerian Inhibiting Substance may offer value in assessing risk of OHSS and diagnosis of PCOS.

CONCLUSION(S)

Potential advantages of MIS compared with other conventional markers of ovarian reserve include: 1) MIS is the earliest marker to change with age; 2) it has the least intercycle variability; 3) it has the least intracycle variability; and 4) it may be informative if randomly obtained during the cycle. Widespread clinical use of MIS may await the availability of an international standard for MIS so that results using different assays may be reliably compared.

Novel pathways that contribute to the anti-proliferative and chemopreventive activities of calcitriol in prostate cancer

Calcitriol, the hormonally active form of Vitamin D, inhibits the growth and development of many cancers through multiple mechanisms. Our recent research supports the contributory role of several new and diverse pathways that add to the mechanisms already established as playing a role in the actions of calcitriol to inhibit the development and progression of prostate cancer (PCa). Calcitriol increases the expression of insulin-like growth factor binding protein-3 (IGFBP-3), which plays a critical role in the inhibition of PCa cell growth by increasing the expression of the cell cycle inhibitor p21. Calcitriol inhibits the prostaglandin (PG) pathway by three actions: (i) the inhibition of the expression of cyclooxygenase-2 (COX-2), the enzyme that synthesizes PGs, (ii) the induction of the expression of 15-prostaglandin dehydrogenase (15-PGDH), the enzyme that inactivates PGs and (iii) decreasing the expression of EP and FP PG receptors that are essential for PG signaling. Since PGs have been shown to promote carcinogenesis and progression of multiple cancers, the inhibition of the PG pathway may add to the ability of calcitriol to prevent and inhibit PCa development and growth. The combination of calcitriol and non-steroidal anti-inflammatory drugs (NSAIDs) result in a synergistic inhibition of PCa cell growth and offers a potential therapeutic strategy. Mitogen activated protein kinase phosphatase 5 (MKP5) is a member of a family of phosphatases that are negative regulators of MAP kinases. Calcitriol induces MKP5 expression in prostate cells leading to the selective dephosphorylation and inactivation of the stress-activated kinase p38. Since p38 activation is pro-carcinogenic and is a mediator of inflammation, this calcitriol action, especially coupled with the inhibition of the PG pathway, contributes to the chemopreventive activity of calcitriol in PCa. Mullerian Inhibiting Substance (MIS) has been evaluated for its inhibitory effects in cancers of the reproductive tissues and is in development as an anti-cancer drug. Calcitriol induces MIS expression in prostate cells revealing yet another mechanism contributing to the anti-cancer activity of calcitriol in PCa. Thus, we conclude that calcitriol regulates myriad pathways that contribute to the potential chemopreventive and therapeutic utility of calcitriol in PCa.