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The development of upper tract urothelial carcinoma (UTUC) has been associated with the ingestion of aristolochic acid (AA) in Chinese herbs. The tumors are more malignant and patients have a worse prognosis in China compared with that in Western countries. Recently, whole-genome and exome sequencing of AA-associated UTUCs found that the most frequently mutated gene was lysine demethylase 6A (KDM6A). However, its biological role and clinical significance have not yet been defined in patients with UTUC in China. A total of 108 surgically resected UTUC samples were obtained. Using immunohistochemistry, the protein expression level of KDM6A in the tumors was investigated together with the clinical and pathological characteristics of the patients, including survival times. In the present study, the expression level of KDM6A was significantly lower in UTUC specimens compared with that in samples from the normal urothelium. Lower KDM6A expression was also found to be significantly associated with a higher tumor grade and shorter cancer-specific and disease-free survival times (P=0.023 and P=0.033, respectively). In addition, using immunohistochemical analysis, no positive association was found between KDM6A expression and the expression of H3K27me3 or histone-lysine N-methyltransferase EZH2, a histone methyltransferase that generates H3K27me3. The results of the present study indicated that decreased KDM6A expression level was significantly associated with tumor grade and decreased survival time in UTUC, suggesting that KDM6A expression could be used as a prognostic marker in patients with UTUC in China. [ABSTRACT FROM AUTHOR]

Some studies suggest that the inactivation of the Ras-MAPK pathway in trophoblast cells can lead to recurrent abortion, but the molecular mechanism underlying the inactivation of this pathway in trophoblast cells is still unclear. This study aimed to explore the relationship between the mechanism of abnormal activation of RASA1, a regulatory protein of the Ras-MAPK pathway, and unexplained recurrent spontaneous abortion. RT-qPCR was used to detect the transcription levels of RASA1 gene. Immunohistochemistry and Western blot were used to detect the expression levels of the RASA1, Raf and MEK proteins. CCK-8, TUNEL and Transwell assays were used to detect the proliferative, apoptotic, and invasive capacities of HTR-8/SVneo cells. ChIP assays were used to detect the enrichment of H3K27me3 in RASA1 gene promoter. Abortion villi experiments showed that the enrichment of H3K27me3 in the RASA1 gene promoter was reduced, and that both RASA1 gene transcription and RASA1 protein expression were increased. Cell experiments confirmed that RASA1 could decrease the phosphorylated Raf and MEK proteins, inhibit the proliferation and invasion ability, and promote the apoptosis ability of HTR-8/SVneo cells. It was also found that the proliferation and invasion ability as well as the Ras-MAPK pathway activity of HTR-8/SVneo cells were inhibited when treated with histone methyltransferase inhibitor DZNep. RASA1 gene was abnormally activated in unexplained recurrent spontaneous abortion villi due to the decreased enrichment of H3K27me3 in the gene promoter. High expression of RASA1 could inhibit the activity of the Ras-MAPK pathway, and thus inhibit the proliferation and invasion ability of trophoblast cells., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Ependymal tumors are pathologically defined intrinsic neoplasms originating in the intracranial compartments or the spinal cord that affect both children and adults. The recently integrated classification of ependymomas based on both histological and molecular characteristics is capable of subgrouping patients with various prognoses. However, the application of histological and molecular markers in Chinese patients with ependymomas has rarely been reported. We aimed to demonstrate the significance of histological characteristics, the v-relavian reticuloendotheliosis viral oncogene homolog A (RELA) fusions and other molecular features in ependymal tumors.Methods: We reviewed the histological characteristics of ependymal tumors using conventional pathological slides and investigate the RELA fusions and Cylclin D1 (CCND1) amplification by Fluorescence in situ hybridization (FISH) and trimethylation of histone 3 lysine 27 (H3K27me3) expression by immunohistochemistry (IHC) methods. SPSS software was used to analyze the data.Results: We demonstrated that hypercellularity, atypia, microvascular proliferation, necrosis, mitosis, and an elevated Ki-67 index, were tightly associated with an advanced tumor grade. Tumor location, necrosis, mitosis and the Ki-67 index were related to the survival of the ependymomas, but Ki67 was the only independent prognostic factor. Additionally, RELA fusions, mostly presented in pediatric grade III intracranial ependymomas, indicated decreased survival times of patients, and closely related to the patients' age, tumor grade, cellularity, cellular atypia, necrosis and Ki67 index in the intracranial ependymal tumors, whereas reduction of H3K27me3 predicted the worse prognosis in ependymal tumors.Conclusions: Histological and molecular features facilitate tumor grading and prognostic predictions for ependymal tumors in Chinese patients. [ABSTRACT FROM AUTHOR]

Aims: Jumonji AT-rich interactive domain 2 (Jarid2) is an interacting component of PRC2 which catalyzes methylation of H3K27 (H3K27me3) and causes the downregulation of PTEN. In the present study, we aimed to explore whether Jarid2 could interact with H3K27me3 to regulate PTEN expression in bladder cancer., Main Methods: Jarid2 expression in bladder cancer tissues and cells were determined by western blotting and RT-PCR. CCK-8, flow cytometry, transwell chamber and in vivo xenograft assays were performed to assess cell growth, apoptosis, migration and tumorigenesis, respectively. Chromatin immunoprecipitation (ChIP) assay was used to assess the methylation of PTEN., Key Findings: Jarid2 expression was increased in bladder cancer tissues and cells. Downregulation of Jarid2 with shRNA transfection obviously inhibited the proliferation, migration and tumorigenesis of bladder cancer T24 and HT-1376 cells and induced cell apoptosis. Jarid2 downregulation decreased the expression of p-AKT and increased PTEN expression. Besides, Jarid2 down-regulation repressed the epithelial-mesenchymal transition (EMT), whereas knockdown of PTEN impaired this effect. Moreover, upregulation of Jarid2 increased the combination of PTEN promoter and H3K27me3, and 5-aza-CdR rescued it. Meanwhile, 5-aza-CdR administration abolished Jarid2 roles in the promotion of EMT process and AKT activation, as well as the reduction of PTEN expression., Significance: Overall, the present study elaborated that Jarid2 facilitated the progression of bladder cancer through H3K27me3-mediated PTEN downregulation and AKT activation, which might provide a new mechanism for Jarid2 in promoting bladder cancer progression., (Copyright © 2019 Elsevier Inc. All rights reserved.)