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P21-activated kinase 5 (PAK5) belongs to the PAK-II subfamily, which is an important regulator of cell survival, adhesion, and motility. However, the functions of PAK5 in endometriosis remain unclear. Here, PAK5 is strikingly upregulated in endometriosis. Furthermore, the knockdown of PAK5 or its inhibitor GNE 2861 blocks the development of endometriosis, which is equally demonstrated in PAK5-knockout mice. In addition, PAK5 promotes glycolysis by enhancing the protein stability of pyruvate kinase 2 (PKM2) in endometriotic cells, which is a key enzyme for glucose metabolism. Moreover, the phosphorylation of PKM2 at Ser519 by PAK5 mediates endometriosis cell proliferation and metastasis. Collectively, PAK5 plays an indispensable role in endometriosis. Our findings demonstrate that PAK5 is an important target for the treatment of endometriosis.
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Aberrant cell proliferation is a hallmark of cancer, including breast cancer. Here, we show that USP27X is required for cell proliferation and tumorigenesis in breast cancer. We identify a PIM2-USP27X regulator of MYC signaling axis whose activity is an important contributor to the tumor biology of breast cancer. PIM2 phosphorylates USP27X, and promotes its deubiquitylation activity for MYC, which promotes its protein stability and leads to increase HK2-mediated aerobic glycolysis in breast cancer. Moreover, the PIM2-USP27X-MYC axis is also validated in PIM2-knockout mice. Taken together, these findings show a PIM2-USP27X-MYC signaling axis as a new potential target for breast cancer treatment.
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Neoplasias de la Mama , Glucólisis , Proteínas Proto-Oncogénicas c-myc , Proteínas Proto-Oncogénicas , Ubiquitinación , Humanos , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Animales , Femenino , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Ratones , Fosforilación , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proliferación Celular , Progresión de la Enfermedad , Ratones Noqueados , Línea Celular Tumoral , Transducción de SeñalRESUMEN
Ovarian endometriosis is a common gynecological disease, and one of its most significant symptoms is infertility. In patients with endometriosis, defects in endometrial decidualization lead to impaired endometrial receptivity and embryo implantation, thus affecting early pregnancy and women's desire to have children. However, the mechanisms underlying the development of endometriosis and its associated defective decidualization are unclear. We find that NEK2 expression is increased in the ectopic and eutopic endometrium of patients with endometriosis. Meanwhile, NEK2 interacts with FOXO1 and phosphorylates FOXO1 at Ser184, inhibiting the stability of the FOXO1 protein. Importantly, NEK2-mediated phosphorylation of FOXO1 at Ser184 promotes cell proliferation, migration, invasion and impairs decidualization. Furthermore, INH1, an inhibitor of NEK2, inhibits the growth of ectopic lesions in mouse models of endometriosis and promotes endometrial decidualization in mouse models of artificially induced decidualization. Taken together, these findings indicate that NEK2 regulates the development of endometriosis and associated disorders of decidualization through the phosphorylation of FOXO1, providing a new therapeutic target for its treatment.
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Proliferación Celular , Endometriosis , Endometrio , Proteína Forkhead Box O1 , Quinasas Relacionadas con NIMA , Femenino , Endometriosis/metabolismo , Endometriosis/patología , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Humanos , Animales , Fosforilación , Ratones , Quinasas Relacionadas con NIMA/metabolismo , Quinasas Relacionadas con NIMA/genética , Endometrio/metabolismo , Endometrio/patología , Movimiento Celular , Decidua/metabolismo , Decidua/patología , Adulto , Modelos Animales de EnfermedadRESUMEN
Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy failures, which brings tremendous stress to women of childbearing age and seriously affects family well-being. However, the reason in about 50% of cases remains unknown and is defined as unexplained recurrent spontaneous abortion (URSA). The immunological perspective in URSA has attracted widespread attention in recent years. The embryo is regarded as a semi-allogeneic graft to the mother. A successful pregnancy requires transition to an immune environment conducive to embryo survival at the maternal-fetal interface. As an important member of regulatory immunity, regulatory T (Treg) cells play a key role in regulating immune tolerance at the maternal-fetal interface. This review will focus on the phenotypic plasticity and lineage stability of Treg cells to illustrate its relationship with URSA.
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ALKBH5 is a master regulator of N6-methyladenosine (m6A) modification, which plays a crucial role in many biological processes. Here, we show that ALKBH5 is required for breast tumor growth. Interestingly, PRMT6 directly methylates ALKBH5 at R283, which subsequently promotes breast tumor growth. Furthermore, arginine methylation of ALKBH5 by PRMT6 increases LDHA RNA stability via m6A demethylation, leading to increased aerobic glycolysis. Moreover, PRMT6-mediated ALKBH5 arginine methylation is confirmed in PRMT6-knockout mice. Collectively, these findings identify a PRMT6-ALKBH5-LDHA signaling axis as a novel target for the treatment of breast cancer.
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Desmetilasa de ARN, Homólogo 5 de AlkB , Arginina , Neoplasias de la Mama , Glucólisis , Proteína-Arginina N-Metiltransferasas , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Femenino , Humanos , Ratones , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Metilación , Arginina/metabolismo , Arginina/análogos & derivados , Arginina/genética , Carcinogénesis/genética , Ratones Noqueados , Línea Celular Tumoral , Proteínas NuclearesRESUMEN
BACKGROUND: The COVID-19 pandemic is an unprecedented health crisis that has affected in vitro fertilization practices globally. Previous studies have shown that SARS-CoV-2 impacts the quality of embryos by inducing an immunological response in infertile patients. In this study, the early embryonic development of SARS-CoV-2-infected infertile patients was investigated. METHODS: Sixty-five SARS-CoV-2 infected infertile patients and 258 controls were involved in this study. The major outcome parameters for the cycle were analyzed, including the number of oocytes, maturation oocytes, available embryos per cycle, and embryo morpho kinetic characteristics. RESULTS: From SARS-CoV-2 infection until oocyte retrieval, it took an average of 6.63 days. The results revealed that the number of oocytes and high-quality embryos on day 3 dramatically reduced in SARS-CoV-2-infected infertile patients. SARS-CoV-2 was detected in the follicular fluid of three infertile patients. SARS-CoV-2 infection had negatively impacted the number of oocytes in multivariate linear regression models. The early embryonic development in the SARS-CoV-2 infection group had a noticeable delay from the six-cell stage to blastocyst stage. CONCLUSIONS: SARS-CoV-2 infection reduced the number of oocytes and high-quality embryos on day 3. It delays the early embryonic development from the six-cell stage to blastocyst stage and has a negative impact on the quality of embryos.
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COVID-19 , Infertilidad , Femenino , Embarazo , Humanos , SARS-CoV-2 , Pandemias , Oocitos , Desarrollo EmbrionarioRESUMEN
Ovarian endometriosis (EMs) is a benign, estrogen-dependent gynecological disorder. Estrogen receptor beta (ERß), a nuclear receptor for estradiol, plays an important role in the development of ovarian EMs. Here, we investigated the biological significance of aurora kinase A (AURKA) in ovarian EMs and the mechanism by which it regulates ERß. We used immunohistochemical assays to verify that AURKA and ERß were highly expressed in ectopic endometrial tissues. Cell proliferation and colony formation assays were used to demonstrate that AURKA promoted the proliferation of EMs cells. Wound-healing assay, Transwell migration assay, and Matrigel invasion assay further showed that AURKA enhanced the ability of EMs cells to migrate and invade. In addition, AURKA was shown to stimulate glycolysis in EMs cells by measuring the concentration of glucose and lactate in the cell supernatants. Moreover, the AURKA inhibitor alisertib was found to inhibit the progression of ovarian EMs and glycolysis in a mouse model of EMs by measuring ectopic tissues as well as by testing the peritoneal fluid of mice. Furthermore, coimmunoprecipitation assay showed that AURKA interacted with ERß. The rescue experiments confirmed that AURKA regulated the development and glycolysis of ovarian EMs in an ERß-dependent manner. AURKA contributed to the development of ovarian EMs by upregulating of ERß. AURKA may represent a new target for the treatment of ovarian EMs.
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Endometriosis , Neoplasias Ováricas , Animales , Femenino , Humanos , Ratones , Aurora Quinasa A/genética , Aurora Quinasa A/metabolismo , Receptor beta de Estrógeno/metabolismo , GlucólisisRESUMEN
BACKGROUND: Depression is a psychosomatic disorder that affects reproductive health. The number of pregnancies is an important indicator of reproductive health. Multiple pregnancies and births may aggravate the risk of depression in females. However, the evidence of the connection between the number of pregnancies and depression is unclear. We aimed to investigate the relationship between the number of pregnancies and depressive symptoms. METHODS: We used the National Health and Nutrition Examination Survey (NHANES) data with a total of 17,216 women from 2005 to 2020. The number of pregnancies obtained from the self-report questionnaire. Depressive symptoms were measured by the nine-item patient health questionnaire (PHQ-9). Multivariate logistic regression models were used to examine the risk factors of depression. The restricted cubic spline (RCS) was applied to explore the nonlinear relationship. In addition, subgroup analysis was used to support the accuracy of our findings. RESULTS: We found that the number of pregnancies is positively associated with the prevalence of depression. According to the multivariable logistic regression analysis, pregnant women was 1.52-fold higher than the normal group to experience depression in the fully-adjusted model. No interaction between number of pregnancies and covariates in subgroups. LIMITATIONS: This study was cross-sectional, which limits its ability to draw conclusions about the causal relationship between the number of pregnancies and depression. CONCLUSION: In the United States, the number of pregnancies was positively associated with the prevalence of depression. It is critical to register the number of pregnancies for monitoring depressive symptoms.
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Depresión , Embarazo , Humanos , Femenino , Estados Unidos/epidemiología , Depresión/psicología , Encuestas Nutricionales , Estudios Transversales , Factores de Riesgo , Modelos LogísticosRESUMEN
Endometriosis is a common inflammatory disease in women of reproductive age and is highly associated with infertility. However, the molecular mechanism of endometriosis remains unclear. 6-Phosphofructose-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) is a key enzyme in glycolysis and plays an important regulatory role in the development of cancer. Here we found that PFKFB3 is highly expressed in endometriotic tissues. PFKFB3 promotes the proliferation and growth of endometriosis cells. Meanwhile, PFKFB3 promotes glycolysis in endometriosis cells. Furthermore, PFKFB3 promotes migration and invasion of endometriosis cells. On this basis, we found that PFKFB3 promotes epithelial-mesenchymal transition (EMT) in endometriosis cells. PFKFB3 interacts with the essential factor of EMT, ß-catenin, and promotes the protein stability of ß-catenin. In addition, the PFKFB3 inhibitor PFK-015 inhibites the growth of endometriosis cells and the development of endometrial tissue. In conclusion, our study shows that PFKFB3 plays an important role in the development of endometriosis and provides new ideas for the clinical diagnosis or treatment of endometriosis.
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Endometriosis , Femenino , Humanos , beta Catenina/metabolismo , Proliferación Celular , Células Cultivadas , Endometriosis/genética , Endometriosis/metabolismo , Transición Epitelial-Mesenquimal , Fosfofructoquinasa-2/genética , Fosfofructoquinasa-2/metabolismo , Estabilidad ProteicaRESUMEN
STUDY QUESTION: Does oral micronized progesterone result in a non-inferior ongoing pregnancy rate compared to vaginal progesterone gel as luteal phase support (LPS) in fresh embryo transfer cycles? SUMMARY ANSWER: The ongoing pregnancy rate in the group administered oral micronized progesterone 400 mg per day was non-inferior to that in the group administered vaginal progesterone gel 90 mg per day. WHAT IS KNOWN ALREADY: LPS is an integrated component of fresh IVF, for which an optimal treatment regimen is still lacking. The high cost and administration route of the commonly used vaginal progesterone make it less acceptable than oral micronized progesterone; however, the efficacy of oral micronized progesterone is unclear owing to concerns regarding its low bioavailability after the hepatic first pass. STUDY DESIGN, SIZE, DURATION: This non-inferiority randomized trial was conducted in eight academic fertility centers in China from November 2018 to November 2019. The follow-up was completed in April 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 1310 infertile women who underwent their first or second IVF cycles were enrolled. On the day of hCG administration, the patients were randomly assigned to one of three groups for LPS: oral micronized progesterone 400 mg/day (n = 430), oral micronized progesterone 600 mg/day (n = 440) or vaginal progesterone 90 mg/day (n = 440). LPS was started on the day of oocyte retrieval and continued till 11-12 weeks of gestation. The primary outcome was the rate of ongoing pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: In the intention-to-treat analysis, the rate of ongoing pregnancy in the oral micronized progesterone 400 mg/day group was non-inferior to that of the vaginal progesterone gel group [35.3% versus 38.0%, absolute difference (AD): -2.6%; 95% CI: -9.0% to 3.8%, P-value for non-inferiority test: 0.010]. There was insufficient evidence to support the non-inferiority in the rate of ongoing pregnancy between the oral micronized progesterone 600 mg/day group and the vaginal progesterone gel group (31.6% versus 38.0%, AD: -6.4%; 95% CI: -12.6% to -0.1%, P-value for non-inferiority test: 0.130). In addition, we did not observe a statistically significant difference in the rate of live births between the groups. LIMITATIONS, REASONS FOR CAUTION: The primary outcome of our trial was the ongoing pregnancy rate; however, the live birth rate may be of greater clinical interest. Although the results did not show a difference in the rate of live births, they should be confirmed by further trials with larger sample sizes. In addition, in this study, final oocyte maturation was triggered by hCG, and the findings may not be extrapolatable to cycles with gonadotropin-releasing hormone agonist triggers. WIDER IMPLICATIONS OF THE FINDINGS: Oral micronized progesterone 400 mg/day may be an alternative to vaginal progesterone gel in patients reluctant to accept the vaginal route of administration. However, whether a higher dose of oral micronized progesterone is associated with a poorer pregnancy rate or a higher rate of preterm delivery warrants further investigation. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by a grant from the National Natural Science Foundation of China (82071718). None of the authors have any conflicts of interest to declare. TRIAL REGISTRATION NUMBER: This trial was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the number ChiCTR1800015958. TRIAL REGISTRATION DATE: May 2018. DATE OF FIRST PATIENT'S ENROLMENT: November 2018.
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Infertilidad Femenina , Progesterona , Femenino , Embarazo , Recién Nacido , Humanos , Lipopolisacáridos , Fase Luteínica , Transferencia de EmbriónRESUMEN
Cuproptosis is a new form of programmed cell death, which is associated with the mitochondrial TCA (tricarboxylic acid) cycle. But the functions of cuproptosis in endometriosis progression are still unknown. Here, we find that cuproptosis suppresses the growth of endometriosis cells and the growth of ectopic endometrial tissues in a mouse model. FDX1 as a key regulator in cuproptosis pathway could promote cuproptosis in endometriosis cells. Interestingly, FDX1 interacts with G6PD, and reduces its protein stability, which predominantly affects the cellular redox-regulating systems. Then, the reduced G6PD activity enhances cuproptosis via down-regulating NADPH and GSH levels. Collectively, our study demonstrates that FDX1 mediates cuproptosis in endometriosis via G6PD pathway, resulting in repression of endometriosis cell proliferation and metastasis.
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Endometriosis , Animales , Femenino , Ratones , Apoptosis , Proliferación Celular , Endometriosis/genética , Ferredoxinas , Glucosafosfato Deshidrogenasa , Homeostasis , Oxidación-ReducciónRESUMEN
Endometriosis, characterized by ectopic endometrium growth in the extrauterine environment, is one of the most notable diseases of the female reproductive system. Worldwide, endometriosis affects nearly 10 % of women in their reproductive years and causes a significant decline in quality of life. Despite extensive investigations of endometriosis over the past years, the mechanisms of endometriosis pathogenesis remain unclear. In recent years, metabolic factors have increasingly been considered factors in endometriosis. There is compelling evidence regarding the progress of endometriosis in the context of severe metabolic dysfunction. Hence, the curative strategies and ongoing attempts to conquer endometriosis might start with metabolic pathways. This review focuses on metabolic mechanisms and summarizes current research progress. These findings provide valuable information for the non-intrusive diagnosis of the disease and may contribute to the understanding of the pathogenesis of endometriosis.
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Endometriosis , Femenino , Humanos , Endometriosis/etiología , Endometriosis/metabolismo , Endometriosis/patología , Calidad de Vida , Endometrio/metabolismoRESUMEN
Ovarian endometriosis is a common gynecological condition that can cause infertility in women of childbearing age. However, the pathogenesis is still unknown. We demonstrate that the carboxyl terminus of Hsc70-interacting protein (CHIP) is a negative regulator in the development of endometriosis and reduces HMGB1 expression in endometriotic cells. Meanwhile, CHIP interacts with HMGB1 and promotes its ubiquitinated degradation, thereby inhibiting aerobic glycolysis and the progression of endometriosis. Furthermore, the CHIP agonist YL-109 effectively suppresses the growth of ectopic endometrium in endometriosis mouse model, which could be a potential therapeutic approach for endometriosis. In conclusion, our data suggest that CHIP may inhibit the development of endometriosis by suppressing the HMGB1-related glycolysis.
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Endometriosis , Proteína HMGB1 , Ubiquitina-Proteína Ligasas , Animales , Femenino , Humanos , Ratones , Endometriosis/patología , Glucólisis , Proteína HMGB1/metabolismo , Ubiquitinación , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Recurrent spontaneous abortion (RSA) is defined as two or more pregnancy loss, affecting the happiness index of fertility couples. The mechanisms involved in the occurrence of RSA are not clear to date. The primary problem for the maternal immune system is how to establish and maintain the immune tolerance to the semi-allogeneic fetuses. During the pregnancy, decidual macrophages mainly play an important role in the immunologic dialogue. The purpose of this study is to explore decidual macrophages, and to understand whether there is a connection between these cells and RSA by analyzing their phenotypes and functions. Pubmed, Web of Science and Embase were searched. The eligibility criterion for this review was evaluating the literature about the pregnancy and macrophages. Any disagreement between the authors was resolved upon discussion and if required by the judgment of the corresponding author. We summarized the latest views on the phenotype, function and dysfunction of decidual macrophages to illuminate its relationship with RSA.
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Aborto Habitual , Aborto Inducido , Embarazo , Humanos , Femenino , Decidua , MacrófagosRESUMEN
Endometriosis is a common chronic condition characterized by abnormal growth of the endometrium outside the uterus. Heat shock transcription factor 1 (HSF1) is a significant regulator of the proteotoxic stress response and plays an essential role in developing endometriosis. However, the mechanisms regulating HSF1 protein stability in endometriosis remain unclear. Here, we demonstrate that OTUB1 interacts with HSF1 and promotes HSF1 protein stability through deubiquitination. In addition, OTUB1 enhances glycolysis and epithelial-mesenchymal transition of endometriosis cells, leading to promote proliferation, migration, and invasion of endometriosis cells. The progression of endometriosis is inhibited in an OTUB1-knockout mouse model. In summary, OTUB1 promotes the development of endometriosis by up-regulating HSF1. OTUB1/HSF1 axis may become a new therapeutic target for endometriosis.
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Recurrent implantation failure (RIF) is characterized by the absence of implantation after high-grade embryos are transferred to the endometrium by at least three in vitro fertilization cycles. It is one of the most important factors contributing to reproductive failure. After numerous barriers have been overcome to obtain good-quality embryos, RIF causes extreme distress and frustration in women and couples. In recent years, significant progress has been made in understanding how inflammatory factors, which include pro-inflammatory factors, anti-inflammatory factors, chemokines, and other molecules, contribute to RIF. Immunological abnormalities, hypercoagulability, and reproductive diseases are considered potential causes of RIF. In alloimmune disorders, inflammatory factors can affect the success rate of embryo implantation by altering T helper (Th)1/Th2 and Th17/regulatory T cell ratios and causing imbalances of uterine natural killer cells and macrophages. Autoimmune disorders can also lead to RIF. Inflammatory factors also play key roles in RIF-related disorders such as hypercoagulability, chronic endometritis, adenomyosis, hydrosalpinx, and endometriosis. This review focuses on the roles of inflammatory factors in RIF, including immune factors, blood hypercoagulable states, and reproductive diseases such as chronic endometritis, adenomyosis, hydrosalpinx, and endometriosis. It also summarizes the different treatments according to the causes of RIF and discusses the efficacy of sirolimus, peripheral blood mononuclear cells, low-dose aspirin combined with low-molecular-weight heparin, blocking interleukin-22, and gonadotropin-releasing hormone agonists in the treatment of RIF.
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Adenomiosis , Endometriosis , Endometritis , Trombofilia , Femenino , Humanos , Leucocitos Mononucleares , Implantación del Embrión , Fertilización In Vitro , EndometrioRESUMEN
Endometriosis (EM) is one of the vanquished wonted causes of chronic pelvic sting in women and is closely associated with infertility. The long-term, complex, systemic, and post-treatment recurrence of EM wreaks havoc on women's quality of life. Extensive metabolic reprogramming (aerobic glycolysis, glucose overweening intake, and high lactate production) and cancer-like changes have been found in EM, which bears striking similarities to tumorigenesis. The key glycolysis regulator PFKFB4 is overexpressed in EM. However, the mechanism of PFKFB4 in EM remains unknown. We found that PFKFB4 was upregulated and was closely related to the progression of EM. We identified focus PIM2 as a new pioneering adjoin protein of PFKFB4. Vigorous biochemical methods were used to confirm that PIM2 phosphorylated site Thr140 of PFKFB4. PIM2 also could enhance PFKFB4 protein expression through the ubiquitin-proteasome pathway. Moreover, PIM2 expression was really corresponding prevalent with PFKFB4 in endometriosis in vivo. Importantly, phosphorylation of PFKFB4 on Thr140 by PIM2 promoted EM glycolysis and cell growth. Our study demonstrates that PIM2 mediates PFKFB4 Thr140 phosphorylation thus regulating glycolysis and EM progression. We illustrated a new mechanism that PIM2 simulated a central upstream partnership in the regulation of PFKFB4, and reveal a novel means of PIM2-PFKFB4 setting EM growth. Our research provided new theoretical support for further clarifying the reprogramming of EM glucose metabolism, and provided new clues for exploring non-contraceptive treatments for EM.
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Endometriosis , Fosfofructoquinasa-2 , Anaerobiosis , Proliferación Celular/genética , Endometriosis/genética , Femenino , Glucosa/metabolismo , Glucólisis/genética , Humanos , Lactatos , Fosfofructoquinasa-2/genética , Fosfofructoquinasa-2/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Fosforilación , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas/metabolismo , Calidad de Vida , Ubiquitinas/metabolismoRESUMEN
OBJECTIVE: To explore the practicality and effectiveness of a flexible low-dose protocol in the fresh embryo transfer cycle: reducing the total amount of antagonist by increasing the interval between administrations of Cetrotide. METHODS: A total of 211 patients with normal ovarian reserve who accepted GnRH-ant protocol for IVF-ET were selected, and they were randomized to the flexible low-dose antagonist group (test group, n = 101) or the conventional dose antagonist group (control group, n = 110). The initial dose of Cetrotide in the test group was 0.25 mg every other day, and then the dose was adjusted to 0.25 mg every day based on the subsequent luteinizing hormone (LH) levels. The dosage of Cetrotide in the control group was 0.25 mg per day. The primary outcome was the clinical pregnancy rate. Secondary outcomes included the incidence of premature LH rise, total dosage of Cetrotide, number of oocytes retrieved, number of fertilized oocytes, number of high-quality embryos, biochemical pregnancy rate and ongoing pregnancy rate. RESULTS: There was no significant difference in the general condition of the two groups. There was no significant difference in the clinical pregnancy rate (51.49% vs. 48.18%, p = 0.632) or the incidence of premature LH rise (18.81% vs. 15.45%, p = 0.584) between the two groups. However, the amount of Cetrotide used in the test group was significantly lower than that in the conventional dose antagonist group (1.13 ± 0.41 vs. 1.61 ± 0.59 mg, p < 0.001). CONCLUSION: The flexible low-dose antagonist protocol and the conventional dose antagonist protocol were equally effective in people with a normal ovarian reserve in the fresh embryo transfer cycle of IVF-ET.