Endogenous c-Jun N-terminal kinase (JNK) activity marks the boundary between normal and malignant granulosa cells

Regulation of FOXL2 gene in ovarian granulosa cell tumor by JNK inhibitor

To explore the regulatory effect of c-Jun N-terminal kinase (JNK) inhibitor (SP600125) on forkhead box protein L2 (FOXL2) gene in human ovarian granulosa cell tumor cells (KGN cells). The main pathogenic gene FOXL2 of ovarian cancer was screened by bioinformatics method. KGN cells were randomly divided into control group and experimental group. Different concentrations of SP600125 (0.1, 1, 5, 10, 50 µM) were added to the experimental group, and an equal volume of dimethyl sulfoxide (DMSO) was added to the control group. The cells were incubated for 48 h. Cell RNA was extracted and reverse transcribed into cDNA. The mRNA expression level of FOXL2 was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Proteins were extracted, and the expression level of FOXL2 protein was detected by Western blot. The proliferation ability of KGN cells treated with SP600125 was detected by MTT assay. Cell scratch assay was used to detect its migration ability. Different concentrations of JNK inhibitor reduced the expression of FOXL2 in ovarian granulosa cells KGN, and 1 µM had the best inhibitory effect. JNK inhibitor reduces the expression of FOXL2 in ovarian granulosa cell tumor KGN.

Identification and function analysis of Toll-like receptor 4 (TLR4) from Manila clam (Ruditapes philippinarum)

Toll-like receptor 4 (TLR4) is a pattern recognition receptor that activates innate immunity in response to pathogen infection. However, the role of TLR4 in pathogen-induced apoptosis and host immunity in mollusks remains largely unknown. In this study, the TLR4 of the Manila clam Ruditapes philippinarum (RpTLR4) was cloned. The open reading frame of RpTLR4 encodes a protein of 734 amino acids, containing a conserved TIR domain. Phylogenetic analysis revealed that RpTLR4 clusters closely with TLR4s from mollusks. RpTLR4 mRNA was detected in all tested tissues, with notably high expression in hemocytes (428-fold) and gills (657-fold). Subcellular localization showed that RpTLR4 is expressed on the cell membrane. qRT-PCR and western blot analyses demonstrated that RpTLR4 expression was induced in Manila clams after treatment with Vibrio parahaemolyticus. Overexpression of RpTLR4 significantly increased apoptosis levels and the expression of apoptosis-related genes. Conversely, silencing RpTLR4 markedly reduced the apoptosis rate in hemocytes induced by V. parahaemolyticus, indicating that V. parahaemolyticus-induced hemocyte apoptosis depends on RpTLR4 expression. Overall, these findings confirm that RpTLR4 plays a pro-apoptotic role in the response of Manila clams to V. parahaemolyticus infection. This study provides a theoretical foundation for understanding the molecular mechanisms underlying mollusk responses to pathogen infection.

Advanced Granulosa Cell Tumors of the Ovary: A Review with a Focus on Current and Novel Therapeutic Approaches

Granulosa cell tumor (GCT) is the most common nonepithelial ovarian malignancy. Still, it is considered rare, with a paucity of high-level evidence guiding management, particularly in the metastatic setting. Advancements in molecular pathology allowed the identification of several targetable mutations that play an important role in GCT pathogenesis. Although current management approaches rely on guidelines extrapolated from the more common epithelial subtype, the unique histopathologic and molecular characteristics of GCTs entail a more focused approach. Systemic therapy remains the cornerstone treatment for advanced disease, and although chemotherapy has been the standard for decades, targeted treatments have gained considerable attention lately. Due to the rarity of this disease, validation of new therapies in large trials is the rate-limiting step for developing evidence-based recommendations. This review sheds light on pathogenesis, clinical and molecular characteristics, and prognostic factors, and discusses current treatment options including the role of novel therapies and immune checkpoint inhibitors in advanced GCT.

The Role of the Dysregulated JNK Signaling Pathway in the Pathogenesis of Human Diseases and Its Potential Therapeutic Strategies: A Comprehensive Review

JNK is named after c-Jun N-terminal kinase, as it is responsible for phosphorylating c-Jun. As a member of the mitogen-activated protein kinase (MAPK) family, JNK is also known as stress-activated kinase (SAPK) because it can be activated by extracellular stresses including growth factor, UV irradiation, and virus infection. Functionally, JNK regulates various cell behaviors such as cell differentiation, proliferation, survival, and metabolic reprogramming. Dysregulated JNK signaling contributes to several types of human diseases. Although the role of the JNK pathway in a single disease has been summarized in several previous publications, a comprehensive review of its role in multiple kinds of human diseases is missing. In this review, we begin by introducing the landmark discoveries, structures, tissue expression, and activation mechanisms of the JNK pathway. Next, we come to the focus of this work: a comprehensive summary of the role of the deregulated JNK pathway in multiple kinds of diseases. Beyond that, we also discuss the current strategies for targeting the JNK pathway for therapeutic intervention and summarize the application of JNK inhibitors as well as several challenges now faced. We expect that this review can provide a more comprehensive insight into the critical role of the JNK pathway in the pathogenesis of human diseases and hope that it also provides important clues for ameliorating disease conditions.

Clinicopathological analysis of patients with molecularly confirmed stage I adult granulosa cell tumors and prediction of recurrence

OBJECTIVE

Adult granulosa cell tumors (AGCTs) are rare malignancies that accounts for approximately 1% of ovarian neoplasms. As there are currently no well-recognized models for predicting relapse-free survival (RFS), we performed a clinicopathological analysis to identify risk factors for AGCT recurrence.

METHODS

We investigated 130 patients with pathologically diagnosed AGCT as confirmed by the presence of the characteristic FOXL2 C402G mutation.

RESULTS

Most patients had International Federation of Gynecology and Obstetrics stage I disease (n = 122, 95.3%). The 10-year RFS rate was 31.4% (22/70) and mean 10-year RFS was 74.4 (95% CI, 65.2-83.7) months. Ten patients experienced recurrence beyond the 10-year follow-up period. Undergoing fertility sparing surgery, an estrogen receptor-α (ERα) score (>0.25), and a Ki-67 index >15% were independent risk factors for recurrence in patients with stage I disease (bias-corrected C-index: 0.776). We constructed a nomogram with well-fitting calibration plots; the areas under the curve (AUCs) for 5-, and 10-year RFS prediction were 0.883 and 0.906 respectively. A simplified model with 3 predictive factors (ERα score, Ki-67 index, and primary surgical procedure) and 2 risk stratification subgroups (low- and high-risk) was constructed; its AUCs for 5-, and 10-year RFS prediction were 0.825 and 0.850 respectively. Kaplan-Meier survival curves showed significant differences in 10-year RFS between the low- and high-risk groups (p < 0.001).

CONCLUSIONS

The type of primary surgical procedure, ERα score, and Ki-67 index are independent predictors of recurrence for patients with stage I AGCT. Our predictive model based on these factors showed good performance.

JUN promotes chicken female differentiation by inhibiting Smad2

The sex determination and control of poultry is a key problem in production and scientific research despite few studies on regulatory factors, especially transcription factors in sex determination. In the early stage of this study, high-throughput sequencing was used to screen the differentially expressed gene JUN in male and female embryonic stem cells (ESCs) and primordial germ cells (PGCs). The qRT-PCR discovered that the JUN gene significantly increased from embryonic days (E) 2.5 later in chicken embryo development, and the female gonad expression was much higher than that of the male after E14.5. Lentivirus shRNA-JUN, shRNA-Smad2 interference, and OE-JUN overexpression vectors were successfully constructed. After interfering with JUN in vivo, male characteristics appeared in ZW embryonic gonads at E18.5. Meanwhile, the male-specific genes DMRT1 and Sox9 were upregulated, the female-specific genes FOXL2, ESR1, and CYP19A1 were downregulated, and the estradiol in the gonads was significantly decreased. The situation was reversed after the overexpression of JUN, ZZ chicken embryo developed into female sexual characteristics. The double luciferase report has found that the Smad2 promoter activity was significantly upregulated after interference with JUN, and significantly increased after the deletion of the JUN binding site. After the injection of the Smad2-shRNA vector into the blood vessel in vivo, it was discovered that DMRT1 and Sox9 of ZW embryos at E18.5 were downregulated, FOXL2 and CYP19A1 were significantly upregulated, and the gonads show femininity. In conclusion, this study proves that JUN is a key regulator in the process of chicken female sex differentiation, which can inhibit the transcription of Smad2 and promote the synthesis of estradiol, and participate in the process of chicken sex differentiation. This study lays a foundation for the analysis of the molecular mechanism of chicken sex determination and the development of poultry sex control technology.

There is a cycle to cycle variation in ovarian response and pre-hCG serum progesterone level: an analysis of 244 consecutive IVF cycles

We aimed to answer one key question, that was not previously addressed as to whether serum progesterone (P_4-hCG day) and its co-variates (estradiol (E_{2-hCG day}) and the number of retrieved oocytes) of a given cycle can be predictive of the subsequent cycle when both cycles are consecutive and comparable for the stimulation protocol, gonadotropin dose and duration of stimulation. We analyzed such 244 consecutive (< 6 months) IVF cycles in 122 patients with GnRH agonist long protocol and found that P₄, E₂ and the number of retrieved oocytes significantly vary between the two cycles. Although P₄ increased (ranging from 4.7 to 266.7%) in the 2nd cycle in 61 patients, E₂ and the number of retrieved oocytes, which are normally positively correlated with P₄ paradoxically decreased in the 41% and 37.7% respectively, of these same 61 patients. When a similar analysis was done in the 54 out of 122 patients (44.3%) in whom serum P₄ was decreased in the 2nd cycle, the mean decrease in P₄ was − 34.1 ± 23.3% ranging from − 5.26 to − 90.1%. E₂ and the number of retrieved oocytes paradoxically increased in the 42.3% and 40.7% of these 54 patients respectively. P₄ remained the same only in the 7 (5.7%) of these 122 patients. These findings indicate that late follicular phase serum P₄ may change unpredictably in the subsequent IVF cycle. The changes are not always necessarily proportional with ovarian response of previous cycle suggesting that growth characteristics and steroidogenic activities of antral cohorts may exhibit considerable cycle to cycle variations.

Terminal differentiation of human granulosa cells as luteinization is reversed by activin-A through silencing of Jnk pathway

Molecular mechanisms underlying luteinization (terminal differentiation of granulosa and theca cells after ovulation) and luteolysis (demise of corpus luteum) are poorly understood in human ovary. Here we report that activin-A, after binding to its cognate receptors induces a functional luteolytic state and reverses luteinization phenotype by downregulating the expression of the steroidogenic enzymes, LH receptor and VEGF and reducing estradiol (E2) progesterone (P4) production and upregulating FSH receptor and cyclin D1 expression in human primary luteinized granulosa cells. Further, this action of activin-A involves downregulation of JNK signaling pathway and is opposite to that of human chorionic gonadotropin (hCG), which acts as a luteotropic hormone and improves luteal function through the activation of JNK pathway in the same cell type. Reversal of luteinization phenotype in luteal granulosa cells by activin-A potentially makes this hormone an attractive candidate for use under certain clinical situations, where induction of luteolysis and rapid reduction of endogenous sex steroid levels are beneficial such as ovarian hyperstimulation syndrome (OHSS), in which the ovaries hyper-respond to gonadotropin stimulation by producing too many growing follicles along with development of ascites, pleural effusion, and hemo-concentrations as a result of increased vascular permeability and leakage of intravascular volume into third spaces. Our work unveils a previously undefined role for activin-A and JNK signaling pathway in human corpus luteum biology, that might have a direct clinical impact in assisted reproductive technologies.

A comparative molecular analysis of DNA damage response, cell cycle progression, viability and apoptosis of malignant granulosa cells exposed to gemcitabine and cisplatin

We aimed to provide a comparative characterization of DNA damage response elements, survival/apoptosis and cell cycle progression of the malignant granulosa cells exposed to gemcitabine and cisplatin. Malignant granulosa tumor cell lines COV434 and KGN were used for the experiments. Cell viability, proliferation, DNA damage response and apoptosis were investigated. Cell cycle progression was assessed. In vitro estradiol (E₂) and AMH productions of the cells were measured. Exposure of asynchronous malignant granulosa cells to gemcitabine caused growth arrest, induced DNA damage and activated cellular stress pathways, cell cycle checkpoint sensors and triggered apoptosis as evidenced by increased expression of phospho-p38, γ-histone H2AX, phospho-Chk-1/phospho-Chk-2, and cleaved forms of PARP and caspase-3 in a dose dependent manner. In vitro E₂ and AMH productions of the cells were decreased along with reduction in viable cell mass. Cisplatin treatment produced a similar response but it was associated with JNK activation rather than p38. When the cells were synchronized and treated with gemcitabine at G₂/M transition, the degradation of cyclin B1 and dephosphorylation of cdc-2 at Tyr 15 residue did not occur, resulting in cycle arrest. Similar effects on cell cycle progression was also observed in cisplatin. However, it was associated with JNK activation and higher expression of γ-histone H2AX and cleaved forms of caspase-3 and PARP, indicative of more extensive DNA damage and apoptosis in the cells. This descriptive study provides evidence that gemcitabine exerts cytotoxic effects and causes perturbations in cell cycle progression of malignant granulosa cells.

hCG Improves Luteal Function and Promotes Progesterone Output through the Activation of JNK Pathway in the Luteal Granulosa Cells of the Stimulated IVF Cycles†

Human chorionic gonadotropin (hCG) is a luteotropic hormone that promotes the survival and steroidogenic activity of corpus luteum (CL) by acting through luteinizing hormone receptors (LHRs) expressed on luteinized theca and granulosa cells (GCs). Therefore, it is used to support luteal phase in in vitro fertilization (IVF) cycles to improve clinical pregnancy rates and prevent miscarriage. However, the molecular mechanism underlying this action of hCG is not well characterized. To address this question, we designed an in vitro translational research study on the luteal GCs obtained from 58 IVF patients. hCG treatment at different concentrations and time points activated c-Jun N-terminal kinase (JNK) pathway and significantly increased its endogenous kinase activity along with upregulated expression of steroidogenic enzymes (steroidogenic acute regulatory protein (stAR), 3β-Hydroxysteroid dehydrogenase (3β-HSD)) in a dose-dependent manner in the luteal GCs. As a result, in vitro P production of the cells was significantly enhanced after hCG. When JNK pathway was inhibited pharmacologically or knocked-down with small interfering RNA luteal function was compromised, P4 production was declined along with the expression of stAR and 3β-HSD in the cells. Further, hCG treatment after JNK inhibition failed to correct the luteal defect and promote P4 output. Similar to hCG, luteinizing hormone (LH) treatment improved luteal function as well and this action of LH was associated with JNK activation in the luteal GCs. These findings could be important from the perspective of CL biology and luteal phase in human because we for the first time identify a critical role for JNK signaling pathway downstream LHR activation by hCG/LH in luteal GCs.

SUMMARY SENTENCE

JNK signaling pathway plays a central role in the upregulated expression of the steroidogenic enzymes StAR and 3b-HSD and augmented progesterone production by hCG/LH in human luteal granulosa cells.

JNK/STAT signalling pathway is involved in fluoride-induced follicular developmental dysplasia in female mice

Excessive fluoride (F) intake decreases the development of potential oocytes by inducing oxidative stress and apoptosis in female mice in our previous study. This study aims to investigate the underlying mechanisms of F-induced follicular developmental dysplasia. Pathomorphological changes in the ovary tissues were observed under light and transmission electron microscopes. DNA damage and proliferation in granulosa cells were analysed by TUNEL staining and BrdU measurement. The protein expression of cell proliferation related regulatory factors including JNK, STAT3, STAT5, CDK2, CDK4, PCNA and Ki67 in the ovary tissues was measured by immunohistochemistry and Western blot analyses. Results indicated that the structure of granulosa cells in the ovary was seriously damaged by excessive F, evident by the swollen endoplasmic reticulum, mitochondria with vacuoles and nucleus shrinkage. F treatment also considerably enhanced the apoptosis and inhibited the proliferation of granulosa cells. The number of granulosa cells around the oocyte decreased after F treatment. The expression levels of STAT3, CDK2, CDK4 and Ki67 in the ovary tissues were up-regulated, and STAT5 and PCNA did not change significantly after F treatment, whereas JNK expression was down-regulated with increasing F dose. In summary, changes in the expression levels of JNK, STAT3, STAT5, CDK2, CDK4, PCNA and Ki67 in the JNK/STAT signalling pathway are involved in F-induced follicular dysplasia in the ovary.