American Journal of Pathology最新文献

Polycystic Ovary Syndrome (PCOS) is the leading cause of infertility in reproductive-age women. Hyperandrogenism, polycystic ovaries and chronic anovulation are its typical clinical features. However, the correlation between hyperandrogenism and ovarian follicle growth aberrations remains undisclosed. To advance our understanding of the molecular alterations in ovarian granulosa cells (GCs) with excessive androgen, epigenetic changes and affected gene expression in human granulosa-lutein cells (hGCs) and immortalized human GCs (KGN) were evaluated. A PCOS mouse model induced by dihydrotestosterone (DHT) was also established. This study found excessive testosterone significantly decreased the acetylation of lysine 27 on Histone H3 (H3K27ac). H3K27ac chromatin immunoprecipitation sequencing (ChIP-seq) data showed down-regulated expression of cell cycle-related genes (CCND1/CCND3/PCNA), which was confirmed by real-time quantitative PCR and western blot. Testosterone application impeding cell proliferation was also proved by Ki-67 immunofluorescence and flow-cytometric analysis. Moreover, testosterone influenced CK2α nuclear translocation, which increased the phosphorylation level of histone deacetylase 2 (HDAC2). Inhibition of CK2α nuclear translocation or silenced HDAC2 expression efficiently retarded H3K27 acetylation. Meanwhile, PCOS mouse model experiments also demonstrated decreased H3K27ac and enhanced HDAC2 phosphorylation in GCs. Cell proliferation-related genes were also downregulated in PCOS mouse GCs. In conclusion, hyperandrogenism in human and mouse GCs caused H3K27Ac aberrations, which are associated with CK2α nuclear translocation and HDAC2 phosphorylation, participating in abnormal follicle development in PCOS patients.

In breast carcinoma, invasive ductal carcinoma (IDC) is the most common histopathological subtype, and ductal carcinoma in situ (DCIS) is a precursor of IDC. They are often concomitant. The immunohistochemical staining of estrogen receptor (ER)/progesterone receptor (PR) in IDC/DCIS on whole-slide histopathological images (WSIs) can predict the prognosis of patients. However, the inter-observer variability among pathologists in reading WSIs is inevitable. Thus, artificial intelligence (AI) technology is crucial. Herein, IDC/DCIS detection was conducted by deep learning approach, including Faster R-CNN, RetinaNet, SSD300, YOLOv3, YOLOv5, YOLOv7, YOLOv8, and Swin transformer. Their performance was estimated by mean average precision (mAP) values. Cell recognition and counting were performed using AI technology to evaluate the intensity and proportion of ER/PR-immunostained cancer cells in IDC/DCIS. A three-round ring study (RS) was conducted to assess WSIs. A database for modelling the underlying probability distribution of a dataset with labels was established. YOLOv8 exhibits the highest detection performance with an mAP@0.5 of 0.944 and an mAP@0.5-0.95 of 0.790. With the assistance of YOLOv8, the scoring concordance across all pathologists was boosted to excellent in RS3 (0.970) from moderate in RS1 (0.724) and good in RS2 (0.812). Deep learning detection can be applied in clinicopathological field. To facilitate the histopathological diagnosis of IDC/DCIS and immunostaining scoring of ER/PR, a novel AI architecture and well-organized dataset were developed.

Traditional anti-angiogenesis drugs are usually unsatisfactory in hepatocellular carcinoma (HCC) treatment. Therefore, it is urgent to find new precise therapeutic targets and further develop more effective drugs for the treatment of HCC. Vasculogenic mimicry (VM) is different from classical endothelium-dependent angiogenesis and associated with poor prognosis in patients with malignant tumor. However, the mechanism underlying VM occurrence is complex and not fully defined. Immunoglobulin-like transcript (ILT) 4, as a negative regulator of immune response, was recently found expressed in many solid tumors. However, whether and how ILT4 regulate VM remains unclear. In this study, we found VM enriched in HCC tissues especially in tissues from patients who experience relapse within 5 years after surgery. Similarly, ILT4 expression level was also higher in HCC tissues from patients who experience relapse within 5 years after surgery. Linear regression analysis revealed a positive correlation between the expression of ILT4 and VM density. Further, Overexpression/knockdown of ILT4 expression upregulated/downregulated VM related marker, three-dimensional tube formation, the migration and invasion of HCC cell lines in vitro. Mechanistic studies showed that ILT4 promoted VM formation via MAPK/ERK signaling. In conclusion, this study provides a rationale and mechanism for ILT4-mediated postoperative relapse via inducing VM in HCC. The related molecular pathways can be used as novel therapeutic targets for the inhibition of HCC angiogenesis and postoperative relapse.

Metabolic dysfunction-associated steatohepatitis (MASH) is considered the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD), which is the leading cause of chronic liver disease in children. However, the pathogenesis of pediatric MASH remains poorly understood due to the lack of animal models. In this study, we developed a mouse model of pediatric MASH and characterized the hepatic transcriptomic profile using spatial transcriptomics (ST) technology. C57BL/6J mice were fed a western diet (WD) along with weekly injections of carbon tetrachloride (CCl4) from 3 weeks old to 8 weeks old. After 5 weeks of feeding, WD+CCl4-treated mice showed significant liver injury without the development of insulin resistance. Histologically, WD+CCl4 induced key features of type 2 MASH, the most common type observed in children, characterized by liver steatosis, portal inflammation, and portal fibrosis. Through ST analysis of liver tissues, we identified that cluster 0 in the mouse from the WD+CCl4 group was enriched in pathways associated with lipid metabolism. Further investigation revealed that cytochrome p450 2E1 (CYP2E1) was the top marker gene of cluster 0, and its expression was increased in the periportal area of mice from the WD+CCl4 group. These findings suggest that our mouse model of pediatric MASH mirrors the histological features of human MASH, and the upregulation of CYP2E1 may be linked to the disease pathogenesis.

The vaginal epithelium plays pivotal roles in host defense against pathogen invasion, contributing to the maintenance of an acidic microenvironment within the vaginal lumen through the activity of acid-base transport proteins. However, the precise defense mechanisms employed by the vaginal epithelium following bacterial infection remain incompletely understood. This study demonstrated that the bacterial lipopolysaccharide (LPS) potentiated net proton efflux by up-regulating the expression of Na⁺-H⁺ exchanger 1 (NHE1), without affecting other acid-base transport proteins in vaginal epithelial cells. Pharmacological inhibition or genetic knockdown of Toll-like receptor-4 (TLR4) and the extracellular-signal-regulated protein kinase (ERK) signaling pathway effectively counteracted the up-regulation of NHE1 and the enhanced proton efflux triggered by LPS in vaginal epithelial cells. In vivo studies revealed that LPS administration led to luminal acidification through the up-regulation of NHE1 expression in the rat vagina. Moreover, inhibition of NHE exhibited impaired defense against acute bacterial infection in the rat vagina. These findings collectively indicated the active involvement of vaginal epithelial cells in facilitating luminal acidification during acute bacterial infection, offering potential insights into the treatment of bacterial vaginosis.

The dysregulation of N6-methyladenosine (m6A) RNA modification is widely recognized for its crucial roles in various diseases, including pulmonary hypertension (PH). Prior studies have highlighted the significant role of METTL3 in the pathogenesis of PH. Nevertheless, the potential and underlying mechanisms of METTL3 and its inhibitors as targets for PH treatment require further elucidation. In this study, we observed increased levels of METTL3 in various rodent models of PH. In vitro studies revealed that METTL3 silencing or treatment with STM2457, a specific METTL3 inhibitor, attenuated the proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) stimulated by platelet-derived growth factor-BB (PDGF-BB) or hypoxia. Moreover, in vivo experiments using AAV9-mediated METTL3 silencing or STM2457 inhibition demonstrated improvement in SU5416/hypoxia-induced PH in mice. Additionally, m6A RNA immunoprecipitation analysis identified RBPJ as a gene regulated by METTL3 in rodent models of PH. Loss-of-function studies showed that silencing RBPJ could attenuate the changes in the proliferation and migration of PASMCs induced by PDGF-BB or hypoxia. Further studies indicated that METTL3 and YTHDF1 regulate RBPJ mRNA expression in an m6A-dependent manner. These findings indicated that targeting METTL3 may be a promising therapeutic strategy for treating PH, and modulation of RBPJ could offer a potential intervention mechanism.

Retinopathy due neovascularization is one of the major causes of vision loss. To understand the mechanisms underlying retinal neovascularization, using oxygen-induced retinopathy (OIR) model, we performed 2D gel-MALDI-TOF/TOF analysis of normoxic and 24-h post OIR mice pups' retinas. 2D gel analysis revealed that GRP78 is one of the several molecules induced by OIR in the retinal ECs. VEGFA also induced GRP78 expression independent of ER stress response in HRMVECs and depletion of its levels reduced VEGFA-induced EC angiogenic responses. Consistent with these observations, EC-specific deletion of GRP78 inhibited OIR-induced retinal neovascularization. In exploring the mechanisms, we found that GRP78 binds with VE-cadherin and releases adherens junction's but not Wnt-mediated β-catenin and that β-catenin, in turn, via interacting with STAT3 triggers cyclin D1 expression. Furthermore, depletion of β-catenin or cyclin D1 levels negated VEGFA-induced EC angiogenic responses and OIR-induced retinal neovascularization. EC-specific deletion of GRP78 also suppressed OIR-induced vascular leakage. In elucidating the upstream signaling, we found that ATF6 mediates GRP78 induction in the modulation of VEGFA-induced EC angiogenic responses and OIR-induced retinal neovascularization. Together, these observations reveal that GRP78 independent of its response to ER stress is involved in mediating EC angiogenic responses by VEGFA and retinal neovascularization by OIR. In view of these findings, it appears that GRP78 could be a desirable target for drug development against diabetic retinopathy.

Delayed diagnosis and treatment resistance make pancreatic ductal adenocarcinoma (PDAC) mortality rates high. Identifying molecular subtypes can improve treatment, but current methods are costly and time-consuming. In this study, deep learning models were utilized to identify histological features that classify PDAC molecular subtypes based on routine hematoxylin-eosin (H&E)-stained histopathological slides. 97 histopathology slides associated with resectable PDAC from the Cancer Genome Atlas (TCGA) project were utilized to train a deep learning model and tested the performance on 44 needle biopsy material (110 slides) from a local annotated patient cohort. The model achieved balanced accuracy of 96.19% and 83.03% in identifying the classical and basal subtypes of PDAC in the TCGA and the local cohort, respectively. This study provides a promising method to cost-effectively and rapidly classifying PDAC molecular subtypes based on routine H&E slides, potentially leading to more effective clinical management of this disease.