Treatment with anticancer agents induces dysregulation of specific Wnt signaling pathways in human ovarian luteinized granulosa cells in vitro

Bio-characteristics, tissue expression of miR-375 in hypothalamic-pituitary-ovarian axis and its regulation in reproduction-related diseases

Our study concentrated on the expression of miRNA-375 in the hypothalamic-pituitary-gonadal axis of female Hu sheep. The investigation involved cloning the precursor sequence of miR-NA-375, followed by comparison with database entries and subsequent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. In our approach, we obtained ovaries, thalamus, cerebellum, brain, uterus, pituitary gland, hypothalamus, and pineal gland from fertile but nonpregnant Hu ewes. MiRNA extraction kit was used to extract miRNA from the above eight tissues. Real-time fluorescent quantitative polymerase chain reaction was used to evaluate the role of miR-375 in the hy-pothalamic-pituitary-gonadal axis. The results of miR-375 precursor sequence cloning were compared with those of Anopheles gambiae, Apis mellifera, Bos taurus, Drosophila melanogaster, Danio rerio, Fugu rubripes, Gallus gallus, Homo sapiens, Monodelphis domestica, Macaca mulatta, Mus musculus, Pan troglodytes, Rattus norvegicus, Tetraodon nigroviridis, Xenopus tropicalis miR-375 in miRBase database. It was found that oar-miR-375 was highly conserved. Notably, miR-375 expression in the pineal gland was significantly higher (p < 0.01) than that in the ovaries, thalamus, cerebellum, brain, uterus, pituitary gland, hypothalamus. The study also involved predicting miR-375 target genes. GO and KEGG enrichment analyses of these predicted target genes revealed that miR-375 is involved in 182 biological processes, affects 186 cellular components, and participates in 184 molecular functions. In terms of pathway enrichment, miR-375 was linked to nine pathways, including the Hippo, Wnt, and mTOR signaling pathways. This study has validated the interaction between miR-375 and its target gene FZD4, which can be recognized and bound to produce effects. These findings lead to the inference that miR-375 may play a crucial regulatory role in sheep reproduction through the Hippo pathway and Wnt pathway, laying a foundation for further exploration of miR-375's role in this domain.

MicroRNA-3061 downregulates the expression of PAX7/Wnt/Ca2+ signalling axis genes to induce premature ovarian failure in mice

The in-depth mechanisms of microRNA regulation of premature ovarian failure (POF) remain unclear. Crispr-cas9 technology was used to construct transgenic mice. The qPCR and Western blot was used to detect the expression level of genes. H&E staining were used to detect ovarian pathological phenotypes. We found that the expression levels of microRNA-3061 were significantly higher in ovarian granulosa cells (OGCs) of POF mouse models than in controls. The miR-3061+/-/AMH-Cre+/- transgenic mice manifested symptoms of POF. RNA-Seq and luciferase reporter assay confirmed that the PAX7 was one of the target genes negatively regulated by microRNA-3061 (miR-3061-5p). Moreover, PAX7 mediated the expression of non-canonical Wnt/Ca2+ signalling pathway by binding to the motifs of promoters to stimulate the transcriptional activation of Wnt5a and CamK2a. In contrast, specific knock-in of microRNA-3061 in OGCs significantly downregulated the expression levels of PAX7 and inhibited the expression of downstream Wnt/Ca2+ signalling pathway. We also discerned a correlation between the expression levels of mRNAs of the Wnt/Ca2+ signalling pathway and the levels of E2 and FSH in POF patients by examining gene expression in the follicular fluid-derived exosomes of women. We confirmed that overexpression of microRNA-3061 induced proliferative inhibition of OGCs and ultimately induced POF in mice by suppressing the transcription factor PAX7 and downregulating expression levels of its downstream Wnt/Ca2+ signalling pathway genes.

Follicle-intrinsic and spatially distinct molecular programs drive follicle rupture and luteinization during ex vivo mammalian ovulation

During ovulation, the apical wall of the preovulatory follicle breaks down to facilitate gamete release. In parallel, the residual follicle wall differentiates into a progesterone-producing corpus luteum. Disruption of ovulation, whether through contraceptive intervention or infertility, has implications for women's health. In this study, we harness the power of an ex vivo ovulation model and machine-learning guided microdissection to identify differences between the ruptured and unruptured sides of the follicle wall. We demonstrate that the unruptured side exhibits clear markers of luteinization after ovulation while the ruptured side exhibits cell death signals. RNA-sequencing of individual follicle sides reveals 2099 differentially expressed genes (DEGs) between follicle sides without ovulation induction, and 1673 DEGs 12 h after induction of ovulation. Our model validates molecular patterns consistent with known ovulation biology even though this process occurs in the absence of the ovarian stroma, vasculature, and immune cells. We further identify previously unappreciated pathways including amino acid transport and Jag-Notch signaling on the ruptured side and glycolysis, metal ion processing, and IL-11 signaling on the unruptured side of the follicle. This study yields key insights into follicle-inherent, spatially-defined pathways that underlie follicle rupture, which may further understanding of ovulation physiology and advance women's health.

In vitro cytotoxic effects of 5-Fluorouracil on isolated murine ovarian preantral follicles

5 fluorouracil (5FU), an antineoplastic drug, is often utilized in the therapeutic regimen for several types of cancer, including the hepatoblastoma in children. The effects of 5FU on the population of ovarian preantral follicles, which is the largest oocyte reservoir, is still poorly understood. The integrity of the ovarian preantral follicle pool is important for lifelong fertility. The better understanding of such effects may favor intervention strategies to protect fertility in 5FU-treated children and women coping with cancer. To analyze the effects of 5FU on isolated murine secondary follicles in vitro, ovaries were collected from young mice (28-30 days old), and secondary follicles were isolated and cultured for 12 days in basic culture medium, with or without 5FU at concentrations of 0.3 mM, 1 mM, 3 mM, 10 mM, and 30 mM. In the in vitro study, we analyzed the percentage of morphologically normal follicles, antrum formation, follicular diameter, and hormone production. On day 12, oocytes were recovered for in vitro maturation. 5FU treatment did not alter the percentage of morphologically normal follicles. On day 12, only 1, 10, and 30 mM 5FU significantly reduced the percentage of antrum. From day 4 onwards, 5FU treatments significantly reduced follicle diameter. The meiosis resumption rate was significantly lower in all 5FU treatments. 5FU concentrations ≥3 mM reduced estradiol levels. In conclusion, 5FU does not affect follicular morphology. However, 5FU deleteriously affects follicular growth, estradiol production, and oocyte maturation in isolated ovarian follicles.

Preventive effect of swim bladder hydrolysates on cyclophosphamide-induced ovarian injury in mice

AIMS

This study aimed to prepare swim bladder hydrolysate (SBH) with M_n  < 4000 Da, and investigate its effects on cyclophosphamide (CTX)-mediated ovarian injury in mice.

METHODS

Hydrolysates were prepared by heating extraction, enzymatic hydrolysis and ultrafiltration. M_n and distribution of SBH were analyzed via gel filtration chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Changes in the mouse oestrus cycle were determined by cytological examination. The number of follicles was examined using histopathology. Enzyme-linked immunosorbent assays (ELISAs) were used to determine the serum sex hormone levels.

RESULTS

The M_n of SBH, prepared by heating extraction, enzymatic hydrolysis, ultrafiltration, and from different batches, was below 4000 Da, and the preparation process was stable. Compared with the control group, the low-, middle-, and high-dose SBH treatment groups showed different trends in oestrus duration, serum sex hormone levels, and the number of primordial and secondary follicles. The oestrus cycle duration of the high-dose SBH group was longer than that of the model group. The serum luteinizing hormone, follicle-stimulating hormone, and anti-Müllerian hormone levels in the middle-dose group were the closest to those of control group. The number of primordial and secondary follicles in the medium-dose group was significantly higher than that in the model group and closest to those of control group.

CONCLUSION

After heating extraction, trypsin/Flavourzyme hydrolysis and ultrafiltration, a hydrolysate with M_n below 4000 Da could be prepared. We found that a moderate (400 mg/kg) SBH dose resulted in the greatest effect on ovarian injury remission in mice.

5-Fluorouracil disrupts ovarian preantral follicles in young C57BL6J mice

PURPOSE

5-Fluorouracil (5-FU), an anti-cancer drug, has been used for hepatoblastoma (HB) chemotherapy in children, who may have impaired  ovarian follicle pool reserve with lasting effects to reproduction. Therefore, this study aimed to investigate 5-FU effects on survival, growth, and morphology of ovarian preantral follicles from C57BL6J young mice.

METHODS

Experiments were carried-out both in vivo and in vitro. Mice were treated with 5-FU injection (450 mg/kg i.p) or saline and sacrificed 3 days after to obtain ovaries for histology and molecular biology. Ovaries for in vitro studies were obtained from unchallenged mice and cultured under basic culture medium (BCM) or BCM plus 5-FU (9.2, 46.1, 92.2 mM). Preantral follicles were classified according to developmental stages, and as normal or degenerated. To assess cell viability, caspase-3 immunostaining was performed. Transcriptional levels for apoptosis (Bax, Bcl2, p53, Bax/Bcl2) and Wnt pathway genes (Wnt2 and Wnt4) were also analyzed. Ultrastructural analyses were carried-out on non-cultured ovaries. In addition, β-catenin immunofluorescence was assessed in mouse ovaries.

RESULTS

The percentage of all-types normal follicles was significantly lower after 5-FU challenge. A total loss of secondary normal follicles was found in the 5-FU group. The highest 5-FU concentrations reduced the percentage of cultured normal primordial follicles. Large vacuoles were seen in granulosa cells and ooplasm of preantral follicles by electron microscopy. A significantly higher gene expression for Bax and Bax/Bcl2 ratio was seen after 5-FU treatment. A marked reduction in β-catenin immunolabeling was seen in 5-FU-challenged preantral follicles. In the in vitro experiments, apoptotic and Wnt gene transcriptions were significantly altered.

CONCLUSION

Altogether, our findings suggest that 5-FU can deleteriously affect the ovarian follicle reserve by reducing preantral follicles survival.

Low KLOTHO level related to aging is associated with diminished ovarian reserve

OBJECTIVE

To explore the relationship between KLOTHO expression and diminished ovarian reserve (DOR).

DESIGN

A case-control study.

SETTING

Reproductive medicine center.

PATIENT(S)

A total of 157 patients with DOR and 159 control women were recruited from the Centre of Reproductive Medicine, Peking University Third Hospital.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The granulosa cells were isolated from follicular fluid after oocyte retrieval, and the KLOTHO level of granulosa cell was measured using a modified quantitative polymerase chain reaction technique. The serum KLOTHO level was measured by solid-phase sandwich enzyme-linked immunosorbent assay.

RESULT(S)

In both granulosa cells and serum derived from women with DOR, KLOTHO expressions were significantly lower compared with normal ovarian reserve controls. Moreover, KLOTHO expression diminished with advancing age.

CONCLUSION(S)

Diminished KLOTHO expression was associated with DOR. Further longitudinal studies in a similar population accompanying disease progression and mechanism exploration are needed to substantiate the rules of KLOTHO in reproductive aging.

Dihydroartemisinin exposure impairs porcine ovarian granulosa cells by activating PERK-eIF2α-ATF4 through endoplasmic reticulum stress

Dihydroartemisinin (DHA) is an artemisinin derivative commonly used in malaria therapy, and a growing number of studies have focused on the potent anticancer activity of DHA. However, the reproductive toxicity of anticancer drugs is a major concern for young female cancer patients. Previous studies have suggested that DHA can cause embryonic damage and affect oocyte maturation. Here, we explored the side effects of DHA exposure on ovarian somatic cells. We exposed porcine granulosa cells to 5 μM and 40 μM DHA for 24 h or 48 h in vitro. DHA inhibited granulosa cell viability in a dose-dependent manner and, in the 48 h treatment group, DHA enhanced the apoptotic rate. We observed that the levels of intracellular calcium, mitochondrial calcium, and ATP concentration were elevated with DHA treatment. In granulosa cells exposed to DHA, the mRNA levels of endoplasmic reticulum stress-related genes GRP78 and ATF4 were increased. Furthermore, analysis of the unfolded protein response signaling pathway showed that the protein levels of P-PERK, P-eIF2α, and ATF4 were upregulated by DHA exposure. These results demonstrate that in granulosa cells, DHA exposure induces endoplasmic reticulum stress that then activates the PERK/eIF2α/ATF4 signaling pathway, thus providing insight into the mechanism underlying DHA-induced reproductive toxicity, and giving reference to DHA use in females.

Observation of Parthanatos Involvement in Diminished Ovarian Reserve Patients and Melatonin's Protective Function Through Inhibiting ADP-Ribose (PAR) Expression and Preventing AIF Translocation into the Nucleus

Diminished ovarian reserve (DOR) is characterized by the depletion of the ovarian pool, which leads to reductions in oocyte quality and quantity. Studies have suggested that ovarian reserve or ovarian aging is tightly related to apoptosis. However, the cell death mechanism is not comprehensively understood. Parthanatos, a type of poly [ADP-ribose] polymerase 1(PARP1)-dependent and apoptosis-inducing factor (AIF)-mediated cell death, plays a crucial role in various disorders. In the present study, we aimed to investigate whether parthanatos is involved in the pathogenesis of DOR. We recruited 40 patients (20 DOR patients and 20 normal ovarian reserve (NOR) patients) and examined PAR expression and AIF translocation in their isolated cumulus GCs (granulosa cells) by fluorescence microscopy. Our results demonstrated that PAR expression and AIF nuclear translocation were significantly higher in cumulus GCs of DOR patients, suggesting that PARP1-dependent cell death may be associated with DOR pathophysiology. Moreover, we tested the protective function of melatonin on hydrogen peroxide (H₂O₂)-induced parthanatos in human ovarian cancer (IGROV1) cells. Our results demonstrated that H₂O₂ treatment of IGROV1 cells led to excessive protein PARylation and AIF translocation into the nuclei. Melatonin effectively inhibits PARylation, blocks translocation of AIF into the nucleus, and consequently decreases the risk of parthanatos in cumulus GCs.

Response of preantral follicles exposed to quinoxaline: A new compound with anticancer potential

The culture of preantral follicles as an in vitro model to evaluate the toxicity of new anticancer drug has being established. Therefore, the aim of this study was to evaluate the effect of quinoxaline derivative the 2 2- (XYZC 6H 3 -CH=N-NH)-quinoxaline, 1 (QX) on caprine preantral follicles. We evaluate the follicular morphology and activation, proliferation and apoptosis of granulosa cells and finally the protein (ABCB1) and genes expression (cyclin/Cdks), respectively involved in multidrug resistance and cell cycle progression. Ovarian fragments containing primordial and developing follicles were exposed (in vitro culture) to different concentrations of QX (QX1.5, QX3.0 or QX6.0 μM/mL) during 6 days. To evaluate the effect of QX, the ovarian tissue was exposed to Paclitaxel 0.1 μg/mL (PTX - negative control) or in culture media without QX (MEM). At the end of exposure time, we realized that the QX (all concentrations) increased (P < .05) the normal morphology of preantral follicles compared to control (not treated ovarian tissue) or MEM. However, QX6.0 showed a enhanced (P < .05) on follicular activation (burnout) and apoptosis than QX1.5 and QX3.0. Expression of ABCB1 was similar between QX1.5 and QX6.0 and both were lower than control, MEM and PTX. Interestingly, the apoptosis rate in QX3.0 was similar to control and MEM and lower then QX1.5; QX6.0 and PTX. We conclude that quinoxaline may be a promising chemotherapeutic agent, however, other concentrations within a defined range (2-5.5 μM) could be widely investigated.

The comparison of reproductive hormone receptor expressions of the sheep ovary and hormone concentrations in two Chinese breeds

The aim of this research was to investigate the changes in reproductive hormone receptor expressions of the ovary and hormone concentrations between oestrous cycle pattern of two different sheep breeds in China. Ovarian tissues were collected from Chinese Merino (Junken type) and Hu sheep with different reproductive states in spring and autumn. Serum samples were assayed for oestrogen (E2), progesterone (P), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) concentrations by radioimmunoassay during spring. The ovarian expression of hormone receptors (ERα, ERβ, PR, LHR and FSHR) was analysed using real-time reverse transcription polymerase chain reaction (RT-PCR). In Chinese Merino, there was no corpora lutea and ovulation point on the surfaces of ovaries in spring and low basal levels of both LH and P in serum. ERα, ERβ and FSHR were expressed significantly higher in Merino ovaries during anoestrus compared with oestrous or luteal phases of Hu sheep (p < 0.05 or p < 0.01). However, both varieties of sheep exhibited a similar tendency to secrete E2 and FSH. Compared with Hu sheep, FSH levels were slightly higher in Merino serum. In Hu sheep, ERα, ERβ, FSHR, LHR and PR expressed in luteal phase ovaries during spring were significantly lower (p < 0.05, p < 0.01 or p < 0.001) than autumn. Interestingly, LHR and PR expressed in anoestrous ovaries were similar to that in oestrous phase of both sheep breeds. The above results suggest that seasonal reproductive sheep increased the expression of E2 and FSH receptors in ovary during spring may enhance the effects of E2 and FSH on follicular development. It is likely that this enhancement prevents the ovary from progressing to the luteal phase.

Ceramide-1-phosphate has protective properties against cyclophosphamide-induced ovarian damage in a mice model of premature ovarian failure

STUDY QUESTION

Is ceramide-1-phosphate (C1P) an ovarian protective agent during alkylating chemotherapy?

SUMMARY ANSWER

Local administration of C1P drastically reduces ovarian damage induced by cyclophosphamide (Cy) via protection of follicular reserve, restoration of hormone levels, inhibition of apoptosis and improvement of stromal vasculature, while protecting fertility, oocyte quality and uterine morphology.

WHAT IS KNOWN ALREADY

Cancer-directed therapies cause accelerated loss of ovarian reserve and lead to premature ovarian failure (POF). Previous studies have demonstrated that C1P regulates different cellular processes including cell proliferation, cell migration, angiogenesis and apoptosis. This sphingolipid may be capable of modulating vascular development and apoptosis in ovaries affected by chemotherapy.

STUDY DESIGN, SIZE, DURATION

The 6-8-week-old mice were weighed and administered either a single intraperitoneal injection of Cy (75 mg/kg) or an equal volume of saline solution only for control mice. Control and Cy mice underwent sham surgery and received an intrabursal injection of saline solution, while Cy + C1P animal groups received 5 μl C1P, either 0.5 or 1 mM, under the bursa of both ovaries 1 h prior to Cy administration.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Animals were euthanized by cervical dislocation or cardiac puncture 2 weeks after surgery for collection of blood orovary and uterus samples, which were cleaned of adhering tissue in culture medium and used for subsequent assays. Ovaries were used for Western blotting or immunohistochemical and/or histological analyses or steroid extraction, as required (n = 5-8 per group). A set of mice (n = 3/group) was destined for oocyte recovery and IVF. Finally, another set (n = 5-6/group) was separated to study fertility parameters.

MAIN RESULTS AND THE ROLE OF CHANCE

The number of primordial (P < 0.01), primary (P < 0.05) and preantral follicles (P < 0.05) were decreased in Cy-treated mice compared to control animals, while atretic follicles were increased (P < 0.001). In Cy + C1P mice, the ovaries recovered control numbers of these follicular structures, in both C1P doses studied. Cy affected AMH expression, while it was at least partially recovered when C1P is administered as well. Cy caused an increase in serum FSH concentration (P < 0.01), which was prevented by C1P coadministration (P < 0.01). E2 levels in Cy-treated ovaries decreased significantly compared to control ovaries (P < 0.01), whilst C1P restored E2 levels to those of control ovaries (P < 0.01). Cy increased the expression of BAX (P < 0.01) and decreased the expression of BCLX-L compared to control ovaries (P < 0.01). The ovarian BCLX-L:BAX ratio was also lower in Cy-treated mice (P < 0.05). In the Cy + C1P group, the expression levels of BAX, BCLX-L and BCLX-L:BAX ratio were no different than those in control ovaries. In addition, acid sphingomyelinase (A-SMase) expression was higher in Cy-treated ovaries, whilst remaining similar to the control in the Cy + C1P group. Cy increased the apoptotic index (TUNEL-positive follicles/total follicles) in preantral and early antral stages, compared to control ovaries (P < 0.001 and P < 0.01, respectively). C1P protected follicles from this increase. No primordial or primary follicular cells stained for either cleaved caspase-3 or TUNEL when exposed to Cy, therefore, we have found no evidence for follicular reserve depletion in response to Cy being due to apoptosis. Cy caused evident vascular injury, especially in large cortical stromal vessels, and some neovascularization. In the Cy + C1P group, the disruptions in vascular wall continuity were less evident and the number of healthy stromal blood vessels seemed to be restored. In Cy-treated ovaries α-SMA-positive cells showed a less uniform distribution around blood vessels. C1P coadministration partially prevented this Cy-induced effect, with a higher presence of α-SMA-positive cells surrounding vessels. By H&E staining, Cy-treated mice showed endometrial alterations compared to controls, affecting both epithelial and stromal compartments. However, C1P allowed that the stromal tissue to maintain its loose quality and its glandular branches. Cy-treated animals had significantly lower pregnancy rates and smaller litter sizes compared with control mice (P = 0.013 and P < 0.05, respectively), whereas cotreatment with C1P preserved normal fertility. Furthermore, a higher (P < 0.05) proportion of abnormal oocytes was recovered from Cy-treated mice compared to the control, which was prevented by C1P administration.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

The results of this study were generated from an in-vivo animal experimental model, already used by several authors. Further studies on C1P functions in female reproduction in pathological conditions such as chemotherapy-induced ovarian failure and on the safety of use of this sphingolipid are required.

WIDER IMPLICATIONS OF THE FINDINGS

The present findings showed that C1P administration prior to Cy might be a promising fertility preservation strategy in female patients who undergo chemotherapy.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by grants from ANPCyT (PICT 2015-1117), CONICET (PIP 380), Cancer National Institute (INC) and Roemmers Foundation, Argentina. The authors declare no conflicts of interest.

Endometrial mesenchymal stem cells isolated from menstrual blood repaired epirubicin-induced damage to human ovarian granulosa cells by inhibiting the expression of Gadd45b in cell cycle pathway

Background

To explore the effect of mesenchymal stem cells isolated from menstrual blood (MB-MSCs) on epirubicin-induced damage to human ovarian granulosa cells (GCs) and its potential mechanisms.

Methods

The estradiol, progesterone, anti-Müllerian hormone, inhibin A, and inhibin B levels were determined using enzyme-linked immunosorbent assay. The proliferation of GCs was detected by Cell Counting Kit-8 assays. The cell cycle distribution was detected by propidiumiodide single staining. The apoptosis of GCs was determined using Annexin V and 7-AAD double staining. The differentially expressed genes of GCs were analyzed with Affymetrix Human Transcriptome Array 2.0 gene chip and verified with Western blot analysis.

Results

Epirubicin inhibited the secretion of estradiol, progesterone, anti-Müllerian hormone, inhibin A, and inhibin B and the proliferation of GCs; arrested these GCs in G2/M phase; and promoted the apoptosis of GCs. However, MB-MSCs repaired epirubicin-induced damage to GCs. Differentially expressed genes of GCs, Gadd45b, CyclinB1, and CDC2, were found by microarray and bioinformatics analysis. Western blot showed that epirubicin upregulated Gadd45b protein expression and downregulated CyclinB1 and CDC2 protein expression, while MB-MSCs downregulated Gadd45b protein expression and upregulated CyclinB1 and CDC2 protein expression.

Conclusions

MB-MSCs repaired epirubicin-induced damage to GCs, which might be related to the inhibition of Gadd45b protein expression.

Protective effects of mangafodipir against chemotherapy-induced ovarian damage in mice

BACKGROUND

Given the seriousness of chemotherapy-induced ovarian injury in female cancer patients, the preservation of fertility, including through the use of cryopreservation technology and pharmaceuticals, requires investigation. Previous studies have shown that damage to the ovaries is related to oxidative stress caused by anticancer drugs. Therefore, superoxide dismutase (SOD) may represent a key factor in the pharmacological protection of the ovaries. The aim of our study was to identify the effects of mangafodipir, a manganese chelate and SOD-mimetic, on suppression of apoptosis in granulosa cells and primordial follicle activation induced by anticancer drugs.

METHODS

Cell viability assays using methyltrichlorosilane solutions and immunoblotting for cleaved caspase-3 were performed in in vitro experiments with the simultaneous addition of mangafodipir to human non-luteinized granulosa cell line (HGrC) cultures treated with hydrogen peroxide (H₂O₂), cisplatin, or paclitaxel. Count and morphological analyses of follicles at each developing stage in the ovaries and immunohistochemistry for cleaved caspase-3, Ki67 and 4-hydroxynonenal, a marker for oxidative stress, were also performed using mangafodipir-injected 6-week-old female ICR mice treated with cisplatin or paclitaxel. Further, mangafodipir was injected into 6-week-old female BALB/c mice inoculated with ES-2 to analyze whether mangafodipir inhibits the anti-tumor effects of cisplatin or paclitaxel treatment.

RESULTS

Mangafodipir attenuated apoptosis induced by H₂O₂ and anticancer drugs in vitro. Mangafodipir also decreased the expression of 4-hydroxynonenal and reduced cisplatin- and paclitaxel-induced apoptosis in granulosa cells in vivo. In addition, mangafodipir inhibited the loss of primordial follicles. Tumor xenograft studies in mice showed that mangafodipir did not affect anticancer drug antitumor effects.

CONCLUSIONS

Oxidative stress might be one of the mechanisms of cisplatin- and paclitaxel-induced the loss of primordial follicles. Mangafodipir can reduce cisplatin- and paclitaxel-induced apoptosis in granulosa cells and primordial follicle activation partially via its SOD activity. At the same time, mangafodipir might have other potential mechanisms to inhibit the activation of primordial follicles. Further, mangafodipir attenuated the ovarian damage caused by cisplatin and paclitaxel without affecting their antitumor activities. Mangafodipir, therefore, though its efficacy might be limited, may be a new option for the preservation of fertility during anticancer treatment.

Alleviation of endoplasmic reticulum stress protects against cisplatin-induced ovarian damage

BACKGROUND

Cisplatin (CDDP), a widely used chemotherapeutic agent, can induce excessive granulosa cell apoptosis, follicle loss and even premature ovarian insufficiency (POI). However, the mechanism remains elusive, although some studies have indicated the involvement of endoplasmic reticulum stress (ERS). The aim of our study was to investigate the possible mechanism ERS in CDDP-induced granulosa cell apoptosis and follicle loss.

METHODS

A POI mouse model was generated by CDDP. The ovaries samples were collected and processed for isobaric tags for relative and absolute quantification analysis (iTRAQ) to screen out our interested proteins of HSPA5 and HSP90AB1, and the decline in their expression were verified by a real-time quantitative PCR and a western blotting assay. In vitro, human granulosa cells, KGN and COV434 cells were transfected with siRNA targeting HSPA5 and HSP90AB1 and then treated with CDDP, or treated with CDDP with/without CDDP+ 4-phenylbutyric acid (4-PBA) and 3-methyladenine (3-MA). The levels of ERS, autophagy and apoptosis were evaluated by western blotting, DALGreen staining and flow cytometry. In vivo, ovaries from mice that received intraperitoneal injections of saline, CDDP, CDDP+ 4-PBA and CDDP+ 3-MA were assayed by immunofluorescence, hematoxylin and eosin (H&E) staining for follicle counting, and terminal-deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) staining for cell apoptosis assay. The plasma hormone levels were measured by an enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

We have clarified the relationships between ERS, autophagy, and apoptosis in CDDP-induced granulosa cell apoptosis, both in vitro and in vivo. Alleviating ERS by inhibiting HSPA5 and HSP90AB1 attenuated CDDP-induced autophagy and apoptosis. 4-PBA treatment significantly attenuated CDDP-induced cell autophagy and apoptosis in cultured KGN and COV434 cells. However, inhibiting cell autophagy with 3-MA negligibly restored the CDDP-induced changes in ERS and apoptosis. In vivo experiments also demonstrated that treatment with 4-PBA, but not 3-MA, prevented CDDP-induced ovarian damage and hormone dysregulation.

CONCLUSIONS

CDDP-induced ERS could promote autophagy and apoptosis in granulosa cells, causing excessive follicle loss and endocrine disorders. Alleviation of ERS with 4-PBA, but not of autophagy with 3-MA, protect against CDDP-induced granulosa cell apoptosis and ovarian damage. Thus, 4-PBA can be used to protect the ovary during chemotherapy in women.

Different patterns of ovarian recovery after cancer treatment suggest various individual ovarian susceptibilities to chemotherapy

The relationship between early recovery of menstrual activity and blood anti-Müllerian hormone (AMH) concentrations were investigated within the first year post-chemotherapy in 32 young patients with breast cancer. All were treated by surgery and the same chemotherapy protocol (three cycles of FEC100 plus three cycles of taxanes). Menstrual activity, blood AMH (using picoAMH ELISA) and FSH concentrations were measured longitudinally before, during and up to 12 months after the end of chemotherapy (six samples per patient). Among the cohort, 17 patients recovered spontaneous cycles at +6 months (fast recovery) whereas the remaining 15 patients were still amenorrheic at that time (slow recovery). Blood AMH differed between these two subgroups at each time of the recovery phase starting at 3 months post-chemotherapy. The AMH patterns were also different: rapid and large increase in the fast recovery versus slow and partial increase in the slow recovery subgroup. No difference in ovarian recovery was observed between patients with a hormone positive or negative tumour. In conclusion, studying the post-chemotherapy patterns of menstrual activity and AMH, two paces of early ovarian recovery are distinguishable in young breast cancer patients who received the same chemotherapy protocol. This suggests different individual ovarian susceptibilities to chemotherapy.

Effect of integrin‑linked kinase gene silencing on microRNA expression in ovarian cancer

Integrin‑linked kinase (ILK) is overexpressed in ovarian cancer (OC), and ILK gene silencing results in apoptosis in OC cells. In the present study, the mechanism by which ILK induces apoptosis was explored from the perspective of microRNA (miRNA) expression. Alterations in the global miRNA expression profile were detected using a miRNA microarray after OC cells were transduced with an ILK small hairpin RNA lentivirus. ILK silencing led to a significant upregulation of 14 miRNAs by at least 1.5‑fold. These findings were validated by reverse transcription‑quantitative polymerase chain reaction. A pathway analysis of experimentally validated target genes revealed the inhibition of multiple cancer‑associated signaling pathways and the wnt signaling pathway. Compared with cells transfected with scrambled RNA, the ILK‑silenced cells had remarkably lower expression of wnt ligands (wnt3a, wnt4 and wnt5a) and downstream β‑catenin. ILK silencing led to apoptosis of OC cells and impaired the migratory ability. Taken together, the present results suggested that miRNA‑mediated wnt pathway alterations are involved in the anti‑apoptotic role of ILK in OC. It was also indicated that ILK silencing reduced the ability of OC cells to adhere to fibronectin, which may lead to unstable focal contact. Consistently, the phosphorylation levels of focal adhesion kinase and RAC‑α serine/threonine protein kinase were downregulated. The present work demonstrated the first global miRNA expression profile of OC cells when ILK was inhibited, and this expression profile may provide a basis for the development of biomarkers and therapeutic targets for OC.

Lithium Chloride Increases COX-2 Expression and PGE2 Production in a Human Granulosa-Lutein SVOG Cell Line Via a GSK-3β/β-Catenin Signaling Pathway

Lithium chloride (LiCl) is widely prescribed for the treatment of bipolar disorders and is associated with a higher incidence of reproductive adverse effects. Cyclooxygenase (COX)-2 and its derivative, prostaglandin E2 (PGE2), play regulatory roles in the human ovulatory process. Whether LiCl affects ovulation by regulating COX2 expression and PGE2 production in the human ovary is still largely unknown. The aim of this study was to investigate the effect of LiCl on the expression of COX-2 and production of PGE2 in human granulosa-lutein (hGL) cells, as well as the mechanisms underlying this effect. Both immortalized and primary hGL cells were used as research models. Using dual inhibition approaches, our results show that LiCl initiates the hGL cellular action by inhibiting the activity of glycogen synthase kinase-3β [GSK-3β (phosphorylation of GSK-3β)] and activation of extracellular signal-regulated kinase 1/2 (ERK1/2), but not by affecting protein kinase B or cAMP response element binding protein signaling. Additionally, the phosphorylation of GSK-3β, but not ERK1/2, resulted in the stabilization and nuclear localization of β-catenin. Furthermore, knockdown of either β-catenin or GSK-3β reversed the LiCl-induced upregulation of COX-2 expression. These results indicate that LiCl upregulates the expression of COX-2 and the subsequent production of PGE2 through the canonical GSK-3β/β-catenin signaling pathway in hGL cells.

ABCB1 and ABCG2 drug transporters are differentially expressed in non-small cell lung cancers (NSCLC) and expression is modified by cisplatin treatment via altered Wnt signaling

BACKGROUND

Lung cancer (LC) is still the most common cause of cancer related deaths worldwide. Non-small cell lung cancer (NSCLC) accounts for 85% of all LC cases but is not a single entity. It is now accepted that, apart from the characteristic driver mutations, the unique molecular signatures of adeno- (AC) and squamous cell carcinomas (SCC), the two most common NSCLC subtypes should be taken into consideration for their management. Therapeutic interventions, however, frequently lead to chemotherapy resistance highlighting the need for in-depth analysis of regulatory mechanisms of multidrug resistance to increase therapeutic efficiency.

METHODS

Non-canonical Wnt5a and canonical Wnt7b and ABC transporter expressions were tested in primary human LC (n = 90) resections of AC and SCC. To investigate drug transporter activity, a three dimensional (3D) human lung aggregate tissue model was set up using differentiated primary human lung cell types. Following modification of the canonical, beta-catenin dependent Wnt pathway or treatment with cisplatin, drug transporter analysis was performed at mRNA, protein and functional level using qRT-PCR, immunohistochemistry, immune-fluorescent staining and transport function analysis.

RESULTS

Non-canonical Wnt5a is significantly up-regulated in SCC samples making the microenvironment different from AC, where the beta-catenin dependent Wnt7b is more prominent. In primary cancer tissues ABCB1 and ABCG2 expression levels were different in the two NSCLC subtypes. Non-canonical rhWnt5a induced down-regulation of both ABCB1 and ABCG2 transporters in the primary human lung aggregate tissue model recreating the SCC-like transporter pattern. Inhibition of the beta-catenin or canonical Wnt pathway resulted in similar down-regulation of both ABC transporter expression and function. In contrast, cisplatin, the frequently used adjuvant chemotherapeutic agent, activated beta-catenin dependent signaling that lead to up-regulation of both ABCB1 and ABCG2 transporter expression and activity.

CONCLUSIONS

The difference in the Wnt microenvironment in AC and SCC leads to variations in ABC transporter expression. Cisplatin via induction of canonical Wnt signaling up-regulates ABCB1 and ABCG2 drug transporters that are not transporters for cisplatin itself but are transporters for drugs that are frequently used in combination therapy with cisplatin modulating drug response.

The cannabinoid receptor CB1 contributes to the development of ectopic lesions in a mouse model of endometriosis

STUDY QUESTION

Does signaling via the cannabinoid (CB₁) receptor play a role in the pathogenesis of endometriosis in a mouse model?

SUMMARY ANSWER

Mice treated with a CB₁ agonist developed larger ectopic lesions, while less severe lesions developed in the absence of functional CB₁ expression.

WHAT IS KNOWN ALREADY

The expression of components of the endocannabinoid system has been demonstrated in both mouse and human uteri. CB₁ receptors are expressed in human epithelial and stromal cell lines derived from eutopic endometrium and deep infiltrating endometriosis nodules.

STUDY DESIGN, SIZE, DURATION

This was a randomized study in a mouse model of endometriosis. In a first set of experiments, mice with endometriosis were treated with the CB₁ receptor agonist methanandamide (MET) (5 mg/kg, n = 20) on Days 1-5 and 8-12. In a second set of experiments, endometriosis development was evaluated in CB₁^-/- mice and in their wild-type (WT) littermates.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Endometriosis-like lesions were induced in Balb/c and C57/Bl6 mice. Two weeks after disease induction, the lesions were counted, measured and either included for immunohistochemistry analysis or frozen for gene expression profiling by semi-quantitative real-time PCR. To limit the role of chance, the experiments were conducted under standardized laboratory conditions with appropriate controls.

MAIN RESULTS AND THE ROLE OF CHANCE

The lesion total volume was significantly higher in MET-treated compared with vehicle-treated mice (P < 0.05). Expression levels of mRNA for survivin, N-cadherin, integrin β1 and interleukin-6 were increased in the ectopic endometrium of MET-treated versus vehicle-treated mice (P < 0.05). CB₁^-/- recipients that received endometrial tissue fragments from CB₁^-/- donors, WT recipients that received endometrial tissue fragments from CB₁^-/- donors and CB₁^-/- recipients that received endometrial tissue fragments from WT donors all showed a significant reduction in total lesion volume and lower expression of survivin and N-cadherin compared with WT recipients receiving uterine fragments from WT donors (P < 0.05).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

We provide evidence that endocannabinoid signaling via CB₁ receptor plays a role in the development of endometriosis in a mouse model. However, the relative contribution of the CB₁-mediated signaling pathways active in inflammatory, uterine and peritoneal cells remains to be ascertained. Since the study was performed in a mouse model, the significance of the findings in the human system warrants further investigation.

WIDER IMPLICATIONS OF THE FINDINGS

Clarifying the function and regulation of CB₁ and its molecular interactions with endogenous ligands, and how endocannabinoids levels are regulated in women with endometriosis, represent critical areas of research for the potential development of a novel medical treatment of the disease.

STUDY FUNDING/COMPETING INTERESTS

A.M.S. was supported by a fellowship from Fondazione Giorgio Pardi. The authors have no conflicts of interest to declare.

MicroRNA-125a-5p induces mouse granulosa cell apoptosis by targeting signal transducer and activator of transcription 3

OBJECTIVE

Premature ovarian failure, a reproductive dysfunction characterized by follicle loss leads to premature menopause. Apoptosis of granulosa cells may be responsible for the associated follicle depletion. MicroRNAs are expressed abundantly in granulosa cells and play an important role in follicular atresia. Evidence suggests that signal transducer and activator of transcription 3 (STAT3) is involved in follicle growth and female fertility.

METHODS

We incubated cultured mouse granulosa cells (mGCs) with increasing doses of cisplatin (CP) for varying periods. Cell proliferation and apoptosis were measured by Cell Counting Kit-8 assay, flow cytometry, and protein expression of cleaved caspase-3. Western blot analysis was used to assess STAT3 and phospho-STAT3 after mGCs were transfected with a microRNA-125a-5p (miR-125a-5p) mimic and a miR-125a-5p inhibitor, respectively. Luciferase reporter assay was conducted to determine the relationship between miR-125a-5p and STAT3.

RESULTS

CP reduced mGC viability, progesterone levels, and estradiol levels. miR-125a-5p was up-regulated in CP-treated mGCs, whereas STAT3 was down-regulated. Increased apoptosis and cleaved caspase-3 were observed in mGCs transfected with a miR-125a-5p mimic or STAT3 interference fragment. Protein expression of STAT3 and phospho-STAT3 was up-regulated or down-regulated when transfected with a miR-125a-5p inhibitor or miR-125a-5p mimic, respectively. Luciferase reporter assays indicated that miR-125a-5p targets the 3' untranslated region of STAT3.

CONCLUSIONS

Overexpression of miR-125a-5p promotes mGC apoptosis by targeting STAT3. Our findings imply the important role of miR-125a-5p in the pathogenesis of premature ovarian failure.

Using activation status of signaling pathways as mechanism-based biomarkers to predict drug sensitivity

Many complex traits, as drug response, are associated with changes in biological pathways rather than being caused by single gene alterations. Here, a predictive framework is presented in which gene expression data are recoded into activity statuses of signal transduction circuits (sub-pathways within signaling pathways that connect receptor proteins to final effector proteins that trigger cell actions). Such activity values are used as features by a prediction algorithm which can efficiently predict a continuous variable such as the IC50 value. The main advantage of this prediction method is that the features selected by the predictor, the signaling circuits, are themselves rich-informative, mechanism-based biomarkers which provide insight into or drug molecular mechanisms of action (MoA).