Reproductive biology
Abstract
Functional inactivation of tumor suppressor genes drives cancer initiation, progression, and treatment responses. Most tumor suppressor genes are inactivated through 1 of 2 well-characterized mechanisms: DNA-level mutations, such as point mutations or deletions, and promoter DNA hypermethylation. Here, we report a distinct third mechanism of tumor suppressor inactivation based on alterations to the histone rather than DNA code. We demonstrated that PAX2 is an endometrial tumor suppressor recurrently inactivated by a distinct epigenetic reprogramming event in more than 80% of human endometrial cancers. Integrative transcriptomic, epigenomic, 3D genomic, and machine learning analyses showed that PAX2 transcriptional downregulation is associated with replacement of open/active chromatin features (H3K27ac/H3K4me3) with inaccessible/repressive chromatin features (H3K27me3) in a framework dictated by 3D genome organization. The spread of the repressive H3K27me3 signal resembled a pearl necklace, with its length modulated by cohesin loops, thereby preventing transcriptional dysregulation of neighboring genes. This mechanism, involving the loss of a promoter-proximal superenhancer, was shown to underlie transcriptional silencing of PAX2 in human endometrial cancers. Mouse and human preclinical models established PAX2 as a potent endometrial tumor suppressor. Functionally, PAX2 loss promoted endometrial carcinogenesis by rewiring the transcriptional landscape via global enhancer reprogramming. The discovery that most endometrial cancers originate from a recurring epigenetic alteration carries profound implications for their diagnosis and treatment.
Authors
Subhransu S. Sahoo, Susmita G. Ramanand, Ileana C. Cuevas, Yunpeng Gao, Sora Lee, Ahmed Abbas, Xunzhi Zhang, Ashwani Kumar, Prasad Koduru, Sambit Roy, Russell R. Broaddus, Victoria L. Bae-Jump, Andrew B. Gladden, Jayanthi Lea, Elena Lucas, Chao Xing, Akio Kobayashi, Ram S. Mani, Diego H. Castrillon
Abstract
Authors
Anna S. Pollack, Christian A. Kunder, Chandler C. Ho, Josephine Chou, Andrew J. Pollack, Rachel L. P. Geisick, Bing M. Zhang, Robert B. West, James D. Brooks, Jonathan R. Pollack
Abstract
Fibrosis of the lower abdominal muscle (LAM) contributes to muscle weakening and inguinal hernia formation, an ailment affecting a noteworthy fifty percent of men by age 75, necessitating surgical correction as the singular therapy. Despite its prevalence, the mechanisms driving LAM fibrosis and hernia development remain poorly understood. Utilizing a humanized mouse model that replicates elevated skeletal muscle tissue estrogen concentrations akin to aging men, we identified estrogen receptor alpha (ESR1) as a key driver of LAM fibroblast proliferation, extracellular matrix deposition, and hernia formation. Fibroblast-specific ESR1 ablation effectively prevented muscle fibrosis and herniation, while pharmacological ESR1 inhibition with fulvestrant reversed hernias and restored normal muscle architecture. Multiomic analyses on in vitro LAM fibroblasts unveiled an estrogen/ESR1-mediated activation of a distinct profibrotic cistrome and gene expression signature, concordant with observations in inguinal hernia tissues in human males. Our findings hold significant promise for prospective medical interventions targeting fibrotic conditions and presenting non-surgical avenues for addressing inguinal hernias.
Authors
Tanvi Potluri, Tianming You, Ping Yin, John S. Coon V, Jonah J. Stulberg, Yang Dai, David J Escobar, Richard L. Lieber, Hong Zhao, Serdar E. Bulun
Abstract
Although premature ovarian insufficiency (POI), a common cause of female infertility and subfertility, has a well-established hereditary component, the genetic factors currently implicated in POI account for only a limited proportion of cases. Here, using an exome-wide, gene-based case-control analysis in a discovery cohort comprising 1,027 POI cases and 2,733 ethnically matched women controls from China, we found that heterozygous loss-of-function (LoF) variants of MAX dimerization protein (MGA) were significantly enriched in the discovery cohort, accounting for 2.6% of POI cases, while no MGA LoF variants were found in the matched control females. Further exome screening was conducted in 4 additional POI cohorts (2 from China and 2 from the United States) for replication studies, and we identified heterozygous MGA LoF variants in 1.0%, 1.4%, 1.0%, and 1.0% of POI cases, respectively. Overall, a total of 37 distinct heterozygous MGA LoF variants were discovered in 38 POI cases, accounting for approximately 2.0% of the total 1,910 POI cases analyzed in this study. Accordingly, Mga+/− female mice were subfertile, exhibiting shorter reproductive lifespan and decreased follicle number compared with WT, mimicking the observed phenotype in humans. Our findings highlight the essential role of MGA deficiency for impaired female reproductive ability.
Authors
Shuyan Tang, Ting Guo, Chengcheng Song, Lingbo Wang, Jun Zhang, Aleksandar Rajkovic, Xiaoqi Lin, Shiling Chen, Yujun Liu, Weidong Tian, Bangguo Wu, Shixuan Wang, Wenwen Wang, Yunhui Lai, Ao Wang, Shuhua Xu, Li Jin, Hanni Ke, Shidou Zhao, Yan Li, Yingying Qin, Feng Zhang, Zi-Jiang Chen
Abstract
To identify novel genes responsible for recurrent hydatidiform moles (HMs), we performed exome sequencing on 75 unrelated patients who were negative for mutations in the known genes. We identified biallelic deleterious variants in 6 genes, FOXL2, MAJIN, KASH5, SYCP2, MEIOB, and HFM1, in patients with androgenetic HMs, including a familial case of 3 affected members. Five of these genes are essential for meiosis I, and their deficiencies lead to premature ovarian insufficiency. Advanced maternal age is the strongest risk factor for sporadic androgenetic HM, which affects 1 in every 600 pregnancies. We studied Hfm1–/– female mice and found that these mice lost all their oocytes before puberty but retained some at younger ages. Oocytes from Hfm1–/– mice initiated meiotic maturation and extruded the first polar bodies in culture; however, their meiotic spindles were often positioned parallel, instead of perpendicular, to the ooplasmic membrane at telophase I, and some oocytes extruded the entire spindle with all the chromosomes into the polar bodies at metaphase II, a mechanism we previously reported in Mei1–/– oocytes. The occurrence of a common mechanism in two mouse models argues in favor of its plausibility at the origin of androgenetic HM formation in humans.
Authors
Maryam Rezaei, Manqi Liang, Zeynep Yalcin, Jacinta H. Martin, Parinaz Kazemi, Eric Bareke, Zhao-Jia Ge, Majid Fardaei, Claudio Benadiva, Reda Hemida, Adnan Hassan, Geoffrey J. Maher, Ebtesam Abdalla, William Buckett, Pierre-Adrien Bolze, Iqbaljit Sandhu, Onur Duman, Suraksha Agrawal, JianHua Qian, Jalal Vallian Broojeni, Lavi Bhati, Pierre Miron, Fabienne Allias, Amal Selim, Rosemary A. Fisher, Michael J. Seckl, Philippe Sauthier, Isabelle Touitou, Seang Lin Tan, Jacek Majewski, Teruko Taketo, Rima Slim
Abstract
Authors
Giang Pham, Raymond E. Diep, Lucien H. Turner, David B. Haslam, Sing Sing Way
Abstract
Proper action of the female sex steroids, 17β-estradiol (E2) and progesterone (P4) on endometrium is essential for fertility. Beyond its role in regulating the cell cycle, cyclin A2 (CCNA2) also mediates E2 and P4 signaling in vitro, but a potential role in modulating steroid action for proper endometrial tissue development and function is unknown. To fill this gap in our knowledge, we examined human endometrial tissue from fertile and infertile women for CCNA2 expression and correlated this with pregnancy outcome. Functional assessment of CCNA2 was validated in vivo using a conditional Ccna2 uterine deficient mouse model while in vitro function was assessed using human cell culture models. We found that CCNA2 expression was significantly reduced in endometrial tissue, specifically the stromal cells, from women undergoing in vitro fertilization who failed to achieve pregnancy. Conditional deletion of Ccna2 from mouse uterine tissue resulted in an inability to achieve pregnancy which appears to be due to alterations in the process of decidualization, which was confirmed using in vitro models. From these studies, we conclude that CCNA2 expression during the proliferative/regenerative stage of the menstrual cycle acts as a safeguard allowing for proper steroid responsiveness, decidualization and pregnancy. When CCNA2 expression levels are insufficient there is impaired endometrial responsiveness, aberrant decidualization and loss of pregnancy.
Authors
Fatimah Aljubran, Katelyn Schumacher, Amanda Graham, Sumedha Gunewardena, Courtney Marsh, Michael Lydic, Kristin Holoch, Warren B. Nothnick
Abstract
Endometriosis is a debilitating, chronic inflammatory disease affecting ~10% of reproductive age women worldwide with no cure. While macrophages have been intrinsically linked to the pathophysiology of endometriosis, targeting them therapeutically has been extremely challenging due to their high heterogeneity and because these disease-associated macrophages (DAMs) can be either pathogenic or protective. Here, we reported identification of pathogenic macrophages characterized by TET3 overexpression in human endometriosis lesions. We showed that factors from the disease microenvironment upregulated TET3 expression transforming macrophages into pathogenic DAMs. TET3 overexpression stimulated pro-inflammatory cytokine production via a feedback mechanism involving inhibition of let-7 miRNA expression. Remarkably, these cells relied on TET3 overexpression for survival, hence vulnerable to TET3 knockdown. We demonstrated that Bobcat339, a synthetic cytosine derivative, triggered TET3 degradation both in human and mouse macrophages. This degradation was dependent on a VHL E3 ubiquitin ligase whose expression was also upregulated in TET3-overexpressing macrophages. Furthermore, depleting TET3-overexpressing macrophages either through myeloid-specific Tet3 ablation or using Bobcat339 strongly inhibited endometriosis progression in mice. Our results defined TET3-overexpressing macrophages as key pathogenic contributors to and attractive therapeutic targets for endometriosis. Our findings may also be applicable to other chronic inflammatory diseases where DAMs have important roles.
Authors
Haining Lv, Beibei Liu, Yangyang Dai, Feng Li, Stefania Bellone, Yuping Zhou, Ramanaiah Mamillapalli, Dejian Zhao, Muthukumaran Venkatachalapathy, Yali Hu, Gordon G. Carmichael, Da Li, Hugh S. Taylor, Yingqun Huang
Abstract
Reproduction is safeguarded by multiple, often cooperative regulatory networks. Kisspeptin signaling, via KISS1R, plays a fundamental role in reproductive control, primarily by regulation of hypothalamic GnRH neurons. We disclose herein a pathway for direct kisspeptin actions in astrocytes that contributes to central reproductive modulation. Protein-protein-interaction and ontology analyses of hypothalamic proteomic profiles after kisspeptin stimulation revealed that glial/astrocyte markers are regulated by kisspeptin in mice. This glial-kisspeptin pathway was validated by the demonstrated expression of Kiss1r in mouse astrocytes in vivo and astrocyte cultures from humans, rats and mice, where kisspeptin activated canonical intracellular signaling-pathways. Cellular co-expression of Kiss1r with the astrocyte markers, GFAP and S100-β, occurred in different brain regions, with higher percentage in Kiss1- and GnRH-enriched areas. Conditional ablation of Kiss1r in GFAP-positive cells, in the G-KiRKO mouse, altered gene expression of key factors in PGE2 synthesis in astrocytes, and perturbed astrocyte-GnRH neuronal appositions, as well as LH responses to kisspeptin and LH pulsatility, as surrogate marker of GnRH secretion. G-KiRKO mice also displayed changes in reproductive responses to metabolic stress induced by high-fat diet, affecting female pubertal onset, estrous cyclicity and LH-secretory profiles. Our data unveil a non-neuronal pathway for kisspeptin actions in astrocytes, which cooperates in fine-tuning the reproductive axis and its responses to metabolic stress.
Authors
Encarnacion Torres, Giuliana Pellegrino, Melissa Granados-Rodríguez, Antonio C. Fuentes-Fayos, Inmaculada Velasco, Adrian Coutteau-Robles, Amandine Legrand, Marya Shanabrough, Cecilia Perdices-Lopez, Silvia Leon, Shel H. Yeo, Stephen M. Manchishi, Maria J. Sánchez-Tapia, Victor M. Navarro, Rafael Pineda, Juan Roa, Frederick Naftolin, Jesús Argente, Raúl M. Luque, Julie A. Chowen, Tamas L. Horvath, Vicent Prevot, Ariane Sharif, William H. Colledge, Manuel Tena-Sempere, Antonio Romero-Ruiz
Abstract
Early gestational loss occurs in approximately 20% of all clinically recognized human pregnancies and is an important cause of morbidity. Either embryonic or maternal defects can cause loss, but a functioning and receptive uterine endometrium is crucial for embryo implantation. We report that the switch/sucrose nonfermentable (SWI/SNF) remodeling complex containing polybromo-1 (PBRM1) and Brahma-related gene 1 (BRG1) is essential for implantation of the embryonic blastocyst on the wall of the uterus in mice. Although preimplantation development is unaffected, conditional ablation of Pbrm1 in uterine stromal cells disrupts progesterone pathways and uterine receptivity. Heart and neural crest derivatives expressed 2 (Hand2) encodes a basic helix-loop-helix (bHLH) transcription factor required for embryo implantation. We identify an enhancer of the Hand2 gene in stromal cells that requires PBRM1 for epigenetic histone modifications/coactivator recruitment and looping with the promoter. In Pbrm1cKO mice, perturbation of chromatin assembly at the promoter and enhancer sites compromises Hand2 transcription, adversely affects fibroblast growth factor signaling pathways, prevents normal stromal-epithelial crosstalk, and disrupts embryo implantation. The mutant female mice are infertile and provide insight into potential causes of early pregnancy loss in humans.
Authors
Qiliang Xin, Iris Feng, Guoyun Yu, Jurrien Dean
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)