Identification of banana ADA1 gene family members and their expression profiles under biotic and abiotic stresses / 生物工程学报

The Spt-Ada-Gcn5-acetyltransferase (SAGA) is an ancillary transcription initiation complex which is highly conserved. The ADA1 (alteration/deficiency in activation 1, also called histone H2A functional interactor 1, HFI1) is a subunit in the core module of the SAGA protein complex. ADA1 plays an important role in plant growth and development as well as stress resistance. In this paper, we performed genome-wide identification of banana ADA1 gene family members based on banana genomic data, and analyzed the basic physicochemical properties, evolutionary relationships, selection pressure, promoter cis-acting elements, and its expression profiles under biotic and abiotic stresses. The results showed that there were 10, 6, and 7 family members in Musa acuminata, Musa balbisiana and Musa itinerans. The members were all unstable and hydrophilic proteins, and only contained the conservative SAGA-Tad1 domain. Both MaADA1 and MbADA1 have interactive relationship with Sgf11 (SAGA-associated factor 11) of core module in SAGA. Phylogenetic analysis revealed that banana ADA1 gene family members could be divided into 3 classes. The evolution of ADA1 gene family members was mostly influenced by purifying selection. There were large differences among the gene structure of banana ADA1 gene family members. ADA1 gene family members contained plenty of hormonal elements. MaADA1-1 may play a prominent role in the resistance of banana to cold stress, while MaADA1 may respond to the Panama disease of banana. In conclusion, this study suggested ADA1 gene family members are highly conserved in banana, and may respond to biotic and abiotic stress.

Primary synovial sarcoma of lung: a clinicopathological analysis of 12 cases / 中华病理学杂志

Objective: To investigate the clinicopathological features, immunophenotype, molecular features and differential diagnosis of primary synovial sarcoma of the lung (PSSL). Methods: Twelve cases of PSSL were collected at Henan Provincial People's Hospital, during May 2010 and April 2021, and their clinicopathological parameters were summarized. SS18-SSX, H3K27Me3, and SOX2 were added to the original immunomarkers to evaluate their diagnostic value for PSSL. Results: The age of 12 patients when diagnosed ranged from 32 to 75 years (mean of 50 years). There were 7 males and 5 females, 2 left lung cases and 10 right lung cases. Of the 6 patients who underwent surgical resection, five cases were confined to lung tissue (T1), one case had mediastinal invasion (T3), two cases had regional lymph node metastasis (N1), and none had distal metastasis. Microscopically, 11 cases showed monophasic spindle cell type and one case showed biphasic type composed of mainly epithelial cells consisting of cuboidal to columnar cells with glandular and cribriform structures. It was difficult to make the diagnosis by using the biopsy specimens. Immunohistochemistry (IHC) showed CKpan expression in 8 of 12 cases; EMA expression in 11 of 12 case; TLE1 expression in 8 of 12 cases; S-100 protein expression in two of 12 cases; various expression of bcl-2 and vimentin in 12 cases, but no expression of SOX10 and CD34 in all the cases. The Ki-67 index was 15%-30%. The expression of SS18-SSX fusion antibody was diffusely and strongly positive in all 12 cases. SOX2 was partially or diffusely expressed in 8 of 12 cases, with strong expression in the epithelial component. H3K27Me3 was absent in 3 of 12 cases. SS18 gene translocation was confirmed by fluorescence in situ hybridization (FISH) test in all 12 samples. Six cases underwent surgery and postoperative chemotherapy, while the other six cases had chemotherapy alone. Ten patients were followed up after 9-114 months, with an average of 41 months and a median of 26 months. Five patients survived and five died of the disease within two years. Conclusions: PSSL is rare and has a broad morphological spectrum. IHC and molecular tests are needed for definitive diagnosis. Compared with current commonly used IHC markers, SS18-SSX fusion antibody has better sensitivity to PSSL, which could be used as an alternative for FISH, reverse transcription-polymerase chain reaction or next generation sequencing in the diagnosis of PSSL.

Malignant peripheral nerve sheath tumor: a clinicopathological analysis / 中华病理学杂志

Objective: To investigate the clinicopathological, immunophenotypic, and genetic features of malignant peripheral nerve sheath tumor (MPNST). Methods: Twenty-three cases of MPNST were diagnosed at the Jiangsu Province Hospital (the First Affiliated Hospital of Nanjing Medical University), China, between January 2012 and December 2022 and thus included in the study. EnVision immunostaining and next-generation sequencing (NGS) were used to examine their immunophenotypical characteristics and genomic aberrations, respectively. Results: There were 10 males and 13 females, with an age range of 11 to 79 years (median 36 years), including 14 cases of neurofibromatosis type I-associated MPNST and 9 cases of sporadic MPNST. The tumors were located in extremities (7 cases), trunk (4 cases), neck and shoulder (3 cases), chest cavity (3 cases), paraspinal area (2 cases), abdominal cavity (2 cases), retroperitoneum (1 case), and pelvic cavity (1 case). Morphologically, the tumors were composed of dense spindle cells arranged in fascicles. Periphery neurofibroma-like pattern was found in 73.9% (17/23) of the cases. Under low magnification, alternating hypercellular and hypocellular areas resembled marbled appearance. Under high power, the tumor cell nuclei were irregular, presenting with oval, conical, comma-like, bullet-like or wavy contour. In 7 cases, the tumor cells demonstrated marked cytological pleomorphism and rare giant tumor cells. The mitotic figures were commonly not less than 3/10 HPF, and geographic necrosis was often noted. Immunohistochemically, tumor cells were positive for S-100 (14/23, 60.9%) and SOX10 (11/23, 47.8%). The loss of the CD34-positive fibroblastic network encountered in neurofibromas was observed in 14/17 of the MPNST cases. The loss of H3K27me3 expression was observed in 82.6% (19/23) of the cases. Moreover, SDHA and SDHB losses were presented in one case. NGS revealed that NF1 gene loss of function (germline or somatic) were found in all 5 cases tested. Furthermore, four cases accompanied with somatic mutations of SUZ12 gene and half of them had somatic mutations of TP53 gene, while one case with germline mutation in SDHA gene and somatic mutations in FAT1, BRAF, and KRAS genes. Available clinical follow-up was obtained in 19 cases and ranged from 1 to 67 months. Four patients died of the disease, all of whom had the clinical history of neurofibromatosis type Ⅰ. Conclusions: MPNST is difficult to be differentiated from a variety of spindle cell tumors due to its wide spectrum of histological morphology and complex genetic changes. H3K27me3 is a useful diagnostic marker, while the loss of CD34 positive fibroblastic network can also be a diagnostic feature of MPNST. NF1 gene inactivation mutations and complete loss of PRC2 activity are the common molecular diagnostic features, but other less commonly recurred genomic aberrations might also contribute to the MPNST pathogenesis.

METTL14 is a chromatin regulator independent of its RNA N6-methyladenosine methyltransferase activity

METTL3 and METTL14 are two components that form the core heterodimer of the main RNA m6A methyltransferase complex (MTC) that installs m6A. Surprisingly, depletion of METTL3 or METTL14 displayed distinct effects on stemness maintenance of mouse embryonic stem cell (mESC). While comparable global hypo-methylation in RNA m6A was observed in Mettl3 or Mettl14 knockout mESCs, respectively. Mettl14 knockout led to a globally decreased nascent RNA synthesis, whereas Mettl3 depletion resulted in transcription upregulation, suggesting that METTL14 might possess an m6A-independent role in gene regulation. We found that METTL14 colocalizes with the repressive H3K27me3 modification. Mechanistically, METTL14, but not METTL3, binds H3K27me3 and recruits KDM6B to induce H3K27me3 demethylation independent of METTL3. Depletion of METTL14 thus led to a global increase in H3K27me3 level along with a global gene suppression. The effects of METTL14 on regulation of H3K27me3 is essential for the transition from self-renewal to differentiation of mESCs. This work reveals a regulatory mechanism on heterochromatin by METTL14 in a manner distinct from METTL3 and independently of m6A, and critically impacts transcriptional regulation, stemness maintenance, and differentiation of mESCs.

Neuronal Histone Methyltransferase EZH2 Regulates Neuronal Morphogenesis, Synaptic Plasticity, and Cognitive Behavior in Mice / 神经科学通报·英文版

The histone methyltransferase enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2)-mediated trimethylation of histone H3 lysine 27 (H3K27me3) regulates neural stem cell proliferation and fate specificity through silencing different gene sets in the central nervous system. Here, we explored the function of EZH2 in early post-mitotic neurons by generating a neuron-specific Ezh2 conditional knockout mouse line. The results showed that a lack of neuronal EZH2 led to delayed neuronal migration, more complex dendritic arborization, and increased dendritic spine density. Transcriptome analysis revealed that neuronal EZH2-regulated genes are related to neuronal morphogenesis. In particular, the gene encoding p21-activated kinase 3 (Pak3) was identified as a target gene suppressed by EZH2 and H3K27me3, and expression of the dominant negative Pak3 reversed Ezh2 knockout-induced higher dendritic spine density. Finally, the lack of neuronal EZH2 resulted in impaired memory behaviors in adult mice. Our results demonstrated that neuronal EZH2 acts to control multiple steps of neuronal morphogenesis during development, and has long-lasting effects on cognitive function in adult mice.

Research progress of histone acetylation in prevention and treatment of heart failure and new ideas based on traditional Chinese medicine / 中国中药杂志

Chronic heart failure(CHF) has become a worldwide public health problem due to its high morbidity and mortality, which seriously endangers people's lifespan and quality of life. In recent years, the treatment strategy of CHF has shifted its emphasis on short-term improvement and transformation of hemodynamics to long-term repair as well as improvement of the biological properties of heart failure. At present, with the continuous deepening of medical research, it has been found that histone acetylation is closely related to the occurrence and development of CHF. Traditional Chinese medicine, via regulating histone acetylation, delays ventricular remodeling, improves energy metabolism, inhibits fibrosis and cardiomyocyte hypertrophy, and intervenes in the development process of heart failure, thus reducing the mortality and the readmission rate and ultimately improving long-term prognosis. Therefore, this study reviewed the mechanism of histone acetylation in the treatment of heart failure as well as its prevention and treatment with traditional Chinese medicine, to provide reference for clinical treatment of CHF.

Traditional Chinese Medicine Treatment, Gua Sha, can Induce Subtle Molecular Changes in Gene Expression / 生物医学与环境科学（英文）

OBJECTIVE@#Here, we explored molecular changes that could potentially mediate healing effects of Gua Sha - a method employed by the Chinese traditional medicine with proven track records of safe and efficient applications dating back to ancient times as well as support from randomized controlled trials performed by modern medical studies - yet remaining almost entirely unexplored by the modern-day high-throughput methods of the -omics sciences.@*METHODS@#We investigated transcriptome changes occurring shortly after Gua Sha treatment in the whole blood of healthy volunteers using bulk RNA-seq analysis. We applied various analytical tools to identify genes with consistent expression changes in multiple individuals in response to Gua Sha and their networks.@*RESULTS@#We found that while the changes were very subtle and individual-specific, we could identify consistent upregulation of three histone genes. Further analysis of the potential regulatory networks of these histone genes revealed the enrichment of functions involved in the immune response and inflammation.@*CONCLUSION@#The significance of these results in the context of potential effects of Gua Sha and the next steps in exploring the molecular mechanisms of action of this technique are discussed.

Research Progress of Role and Mechanism of SETD7 in Tumor Occurrence and Progression / 中国肺癌杂志

The occurence and development of tumors is a complicated process, which not only depends on the mutation or deletion of genes, but also is affected by epigenetic regulation. Accumulating evidences have shown that epigenetic modifications play fundamental roles in transcriptional regulation, heterochromatin formation, X chromosome inactivation, DNA damage response and tumor development. SET domain containing lysine methyltransferase 7 (SETD7) was initially identified as an important lysine methyltransferase, which methylated histone and non-histone proteins. These modifications play fundamental roles. Once this modification disorders, it can directly lead to cell abnormalities and cause many diseases. Studies have shown that SETD7 is related to the occurence and development of various tumors, but the methylation sites of SETD7 and its regulatory mechanism have not been fully elucidated. This article summarizes the research progress of the role of SETD7 on histone and non-histone methylation modification in tumors and the molecular mechanism, in order to provide new therapeutic targets for tumor pathogenesis and diagnosis.
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Effects of prenatal nicotine exposure on enamel formation of offspring mice / 中华口腔医学杂志

Objective: To investigate the effects of nicotine on the morphology, structure of offspring's dental germ, enamel organ and other dental tissues and the further potential epigenetic mechanisms by establishing prenatal nicotine exposure mouse model. Methods: Ten C57BL/6 pregnant mice were randomly divided into control group (physiological saline subcutaneous injection) and prenatal nicotine exposure (PNE) group (nicotine subcutaneous injection) by using a random number table. Postnatal day 0 (P0), postnatal day 14 (P14) and postnatal day 25 (P25) offspring mice were collected for subsequent experiments. The offspring mice were divided into offspring control group and offspring PNE group according to the maternal group respectively. Weights of P0 and P25 offspring mice were recorded. Micro-CT, scanning electron microscope (SEM) and Vickers hardness test were performed to analyze the related parameters of hard tissues including alveolar bones and mandibular incisors. Total RNAs were extracted from mandible tissues and the third generation of dental epithelial stem cells (DESC) in P25 mice. The relative expression levels of osteogenic and ameloblastic differentiation related genes were measured by real-time quantitative PCR (RT-qPCR). Immunohistochemical stainings of paraffin sections were then performed to observe the distribution and expression level of proliferating cell nuclear antigen (Pcna), amelogenin (Amelx), histone H3 trimethylated at lysine 27 (H3K27me3) and enhancer of zeste homolog 2 (Ezh2). Cell counting kit-8 (CCK-8) assays were used to detect the cell viabilities of DESCs after administrations of different concentrations of nicotine (0.01, 0.1, 1 mmol/L) and GSK126 (an inhibitor of histone methyltransferase Ezh2). Results: Compared with the control group, pregnant mice in PNE group were more likely to have adverse pregnancy outcomes, such as significantly lower offspring body weight [P0: offspring control (1.20±0.04) g, offspring PNE (0.99±0.02) g, P<0.001; P25: offspring control (15.26±1.70) g, offspring PNE (9.65±1.32) g, P<0.001] and increased stillbirths rate [offspring control (0), offspring PNE (46.40±9.30) %, P<0.001]. At P14 and P25, the distance parameters between the enamel mineralized deposits of mandibular incisors and the mesial surface of the first molar in offspring PNE group [P14: (-1 349±45) μm; P25: (-1 192±147) μm] was significantly decreased compared with the control group [P14: (-506±380) μm, P25: (504±198) μm] (P<0.05, P<0.001). The enamel column and enamel column stroma of incisors in offspring PNE group were blurred, arranged loosely and disorderly than those in the control group, while the microhardness of incisor enamel in offspring PNE group [(245.7±18.4) MPa] was significantly lower compared to the control group [(371.9±28.7) MPa] (P<0.001). HE staining showed disordered pre-ameloblast (Pre-Am) arrangement and delayed mineralization deposition point in offspring PNE group compared with the control group, while the length of transit-amplifying cell (TA) and Pre-Am region were prolonged as well. Immunohistochemical staining results displayed that the overall Pcna (P<0.05), H3K27me3 (P<0.01), Ezh2 (P<0.01) expression of labial cervical loop (LaCL) in PNE group were increased, while the positive signal of Amelx in ameloblast cytoplasm was impaired. In vitro, the addition of 1 mmol/L nicotine could significantly upregulate the expression level of Pcna (P<0.01) and downregulate the expression levels of B lymphoma Mo-MLV insertion region 1 (P<0.05), leucine rich repeats and immunoglobulin like domains 1 (P<0.05), Amelx (P<0.01). In addition, 1 mmol/L nicotine could also significantly enhance the proliferation activity of DESCs (P<0.001). Addition of 10 μmol/L GSK126, could rescue the proliferation activation effect of 1 mmol/L nicotine on DESCs. Conclusions: PNE may delay the process of enamel formation and lineage differentiation, leading to the abnormal proliferation of DESCs and changes of epigenetic modification state in H3K27me3, which affect the development of enamel in offspring mice,suggesting PNE might be one of risk environmental factor for tooth development.

Advances of structure and mechanisms of bromodomain-containing protein 4 and its related research in tumors / 生物工程学报

The bromodomain and extraterminal domain (Bet) family are the regulators of the epigenome and also the pivotal driving factors for the expression of tumor related genes that tumor cells depend on for survival and proliferation. Bromodomain-containing protein 4 (Brd4) is a member of the Bet protein family. Generally, Brd4 identifies acetylated histones and binds to the promoter or enhancer region of target genes to initiate and maintain expression of tumor related genes. Brd4 is closely related to the regulation of multiple transcription factors and chromatin modification and is involved in DNA damage repair and maintenance of telomere function, thus maintaining the survival of tumor cells. This review summarizes the structure and function of Brd4 protein and the application of its inhibitors in tumor research.

Role of histone posttranslational modifications in the regulation of ovarian function / 生理学报

The ovary is the reproductive organ of female mammals, which is responsible for producing mature eggs and secreting sex hormones. The regulation of ovarian function involves the ordered activation and repression of genes related to cell growth and differentiation. In recent years, it has been found that histone posttranslational modification can affect DNA replication, damage repair and gene transcriptional activity. Some regulatory enzymes mediating histone modification are co-activators or co-inhibitors associated with transcription factors, which play important roles in the regulation of ovarian function and the development of ovary-related diseases. Therefore, this review outlines the dynamic patterns of common histone modifications (mainly acetylation and methylation) during the reproductive cycle and their regulation of gene expression for important molecular events, focusing on the mechanisms of follicle development and sex hormone secretion and function. For example, the specific dynamics of histone acetylation are important for the arrest and resumption of meiosis in oocytes, while histone (especially H3K4) methylation affects the maturation of oocytes by regulating their chromatin transcriptional activity and meiotic progression. Besides, histone acetylation or methylation can also promote the synthesis and secretion of steroid hormones before ovulation. Finally, the abnormal histone posttranslational modifications in the development of two common ovarian diseases (premature ovarian insufficiency and polycystic ovary syndrome) are briefly described. It will provide a reference basis for understanding the complex regulation mechanism of ovarian function and further exploring the potential therapeutic targets of related diseases.

Mechanism of large-conductance calcium-activated potassium channel involved in inflammatory response in sepsis / 中华危重病急救医学

OBJECTIVE@#To explore the mechanisms of large-conductance calcium-activated potassium channel (BKCa) involved in inflammatory response in sepsis.@*METHODS@#The serum levels of BKCa were measured by enzyme-linked immunosorbent assay (ELISA) in patients with sepsis (28 cases), patients with common infection (25 cases) and healthy people (25 cases). The relationship between levels of BKCa and acute physiology and chronic health evaluation II (APACHE II) were analyzed. Cultured RAW 264.7 cells were stimulated by lipopolysaccharide (LPS). In some experiments, a cell model of sepsis was constructed using Nigericin as the second stimulus signal. The mRNA and protein expressions of BKCa in RAW 264.7 cells stimulated with LPS (0, 50, 100, 1 000 μg/L) were measured by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and Western blotting. RAW 264.7 cells were transfected with small interfering RNA of BKCa (siRNA-BKCa), and the levels of caspase-1 precursor (pro-caspase-1), interleukin-1β precursor (pro-IL-1β) in cell, and the levels of caspase-1 p20, IL-1β p17 of cell culture medium, and NOD-like receptor protein 3 (NLRP3), nuclear factor-κB (NF-κB) were measured by Western blotting. The apoptosis were detected by staining with propidium iodide (PI), the release rate of lactate dehydrogenase (LDH) were measured, and the expression of apoptotic protein Gasdermin D (GSDMD) was measured by Western blotting to evaluate the effect of silencing BKCa on cell pyrosis.@*RESULTS@#The level of serum BKCa in patients with sepsis was significantly higher than that in patients with common infection and health peoples (ng/L: 165.2±25.9 vs. 102.5±25.9, 98.8±20.0, both P < 0.05). In addition, the level of serum BKCa in patients with sepsis was significantly positively correlated with APACHE II score (r = 0.453, P = 0.013). LPS could construct a sepsis cell model by which LPS could promote BKCa expression in mRNA and protein with a concentration-dependent manner. The mRNA and protein expressions of BKCa in the cells stimulated by 1 000 μg/L LPS were significantly higher than that in the blank group (0 μg/L) [BKCa mRNA (2-ΔΔCt): 3.00±0.36 vs. 1.00±0.16, BKCa/β-actin: 1.30±0.16 vs. 0.37±0.09, both P < 0.05]. Compared with the control group, the ratios of caspase-1 p20/pro-caspase-1 and IL-1β p17/pro-IL-1β in the model group were significantly increased (caspase-1 p20/pro-caspase-1: 0.83±0.12 vs. 0.27±0.05, IL-1β p17/pro-IL-1β: 0.77±0.12 vs. 0.23±0.12, both P < 0.05), however, transfection of siRNA-BKCa induced the decrease both of them (caspase-1 p20/pro-capase-1: 0.23±0.12 vs. 0.83±0.12, IL-1β p17/pro-IL-1β: 0.13±0.05 vs. 0.77±0.12, both P < 0.05). Compared with the control group, the number of apoptotic cells, LDH release rate and GSDMD expression in the model group were significantly increased [LDH release rate: (30.60±8.40)% vs. (15.20±7.10)%, GSDMD-N/GSDMD-FL: 2.10±0.16 vs. 1.00±0.16, both P < 0.05], however, transfection of siRNA-BKCa induced the decrease both of them [LDH release rate: (15.60±7.30)% vs. (30.60±8.40)%, GSDMD-N/GSDMD-FL: 1.13±0.17 vs. 2.10±0.16, both P < 0.05]. The mRNA and protein expressions of NLRP3 in sepsis cells were significantly higher than those in the control group [NLRP3 mRNA (2-ΔΔCt): 2.06±0.17 vs. 1.00±0.24, NLRP3/GAPDH: 0.46±0.05 vs. 0.15±0.04, both P < 0.05]. However, the expression of NLRP3 after siRNA-BKCa transfection was significantly lower than that in model group [NLRP3 mRNA (2-ΔΔCt): 1.57±0.09 vs. 2.06±0.17, NLRP3/GAPDH: 0.19±0.02 vs. 0.46±0.05, both P < 0.05]. Compared with the control group, the NF-κB p65 nuclear transfer of sepsis cell were significantly increased (NF-κB p65/Histone: 0.73±0.12 vs. 0.23±0.09, P < 0.05). However, the NF-κB p65 expression in the nucleus were decreased after siRNA-BKCa transfection (NF-κB p65/Histone: 0.20±0.03 vs. 0.73±0.12, P < 0.05).@*CONCLUSIONS@#BKCa is involved in the pathogenesis of sepsis, and its possible mechanism is to activate NF-κB/NLRP3/caspase-1 signaling pathway to induce inflammatory factor production and cell death.

The engagement of histone lysine methyltransferases with nucleosomes: structural basis, regulatory mechanisms, and therapeutic implications

Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression. The structures and functions of HKMTs have been extensively investigated in recent decades, significantly advancing our understanding of the dynamic regulation of histone methylation. Here, we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases), with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs. These structural studies inform HKMTs' roles in tumorigenesis and provide the foundations for developing new therapeutic approaches targeting HKMTs in cancers.

Diffuse midline glioma with H3K27 alteration in adults: a clinicopathological analysis / 中华病理学杂志

Objective: To investigate the clinicopathological characteristics, pathological diagnosis and prognosis of diffuse midline glioma (DMG) with H3K27 alteration in adults. Methods: Twenty cases of H3K27-altered adult DMG diagnosed in the First Affiliated Hospital of Nanjing Medical University were enrolled from 2017 to 2022. All cases were evaluated by clinical and imaging presentations, HE, immunohistochemical staining and molecular genetics; and the relevant literature was reviewed. Results: The ratio of male to female was 1∶1, and the median age was 53 years (range from 25 to 74 years); the tumors were located in the brainstem (3/20, 15%) and non-brainstem (17/20, 85%; three in thoracolumbar spinal cord and one in pineal region). The clinical manifestations were non-specific, mostly dizziness, headache, blurred vision, memory loss, low back pain, limb sensation and/or movement disorders, etc. Microscopically, the tumors showed infiltrative growth, with WHO grade 2 (3 cases), grade 3 (12 cases), and grade 4 (5 cases). The tumors showed astrocytoma-like and oligdendroglioma-like, pilocytic astrocytoma-like and epithelioid-like patterns. Immunohistochemically, the tumor cells were positive for GFAP, Olig2 and H3K27M, and H3K27me3 expression was variably lost. ATRX expression was lost in four cases, p53 was strongly positive in 11 cases. Ki-67 index was about 5%-70%. Molecular genetics showed p. k27m mutation in exon 1 of H3F3A gene in 20 cases; BRAF mutation in two cases: V600E and L597Q mutation in one case each. Follow up intervals ranged from 1 to 58 months, and the survival time for brainstem (6.0 months) and non-brainstem (30.4 months) tumors was significantly different (P<0.05). Conclusions: DMG with H3K27 alteration is uncommonly found in adults, mostly occurs in non-brainstem, and can present in adults of all ages. Owing to the wide histomorphologic features, mainly astrocytic differentiation, routine detection of H3K27me3 in midline glioma is recommended. Molecular testing should be performed on any suspected cases to avoid missed diagnosis. Concomitant BRAF L597Q mutation and PPM1D mutation are novel findings. The overall prognosis of this tumor is poor, with tumors located in the brainstem showing worse outcome.

Knockdown of ACC1 promotes migration of esophageal cancer cell / 中华肿瘤杂志

Objective: To investigate the effect of acetyl-CoA carboxylase 1 (ACC1) knockdown on the migration of esophageal squamous cell carcinoma (ESCC) KYSE-450 cell and underlying mechanism. Methods: Lentiviral transfection was conducted to establish sh-NC control cell and ACC1 knocking down cell (sh-ACC1). Human siRNA HSP27 and control were transfected by Lipo2000 to get si-HSP27 and si-NC. The selective acetyltransferase P300/CBP inhibitor C646 was used to inhibit histone acetylation and DMSO was used as vehicle control. Transwell assay was performed to detect cell migration. The expression of HSP27 mRNA was examined by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and the expressions of ACC1, H3K9ac, HSP27 and epithelial-mesenchymal transition-related proteins E-cadherin and Vimentin were detected by western blot. Results: The expression level of ACC1 in sh-NC group was higher than that in sh-ACC1 group (P<0.01). The number of cell migration in sh-NC group was (159.00±24.38), lower than (361.80±26.81) in sh-ACC1 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC group were statistically significant compared with sh-AAC1 group (P<0.05). The migrated cell number in sh-NC+ si-NC group was (189.20±16.02), lower than (371.60±38.40) in sh-ACC1+ si-NC group (P<0.01). The migrated cell number in sh-NC+ si-NC group was higher than that in sh-NC+ si-HSP27 group (152.40±24.30, P<0.01), and the migrated cell number in sh-ACC1+ si-NC group was higher than that in sh-ACC1+ si-HSP27 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC+ si-NC group were significantly different from those in sh-ACC1+ si-NC and sh-NC+ si-HSP27 groups (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-ACC1+ si-NC group were significantly different from those in sh-ACC1+ si-HSP27 group (P<0.01). After 24 h treatment with C646 at 20 μmmo/L, the migrated cell number in sh-NC+ DMSO group was (190.80±11.95), lower than (395.80±17.10) in sh-ACC1+ DMSO group (P<0.01). The migrated cell number in sh-NC+ DMSO group was lower than that in sh-NC+ C646 group (256.20±23.32, P<0.01). The migrated cell number in sh-ACC1+ DMSO group was higher than that in sh-ACC1+ C646 group (87.80±11.23, P<0.01). The protein expressions of H3K9ac, HSP27, E-cadherin and Vimentin in sh-NC+ DMSO group were significantly different from those in sh-ACC1+ DMSO group and sh-NC+ C646 group (P<0.01). The protein expression levels of H3K9ac, HSP27, E-cadherin and Vimentin in sh-ACC1+ DMSO group were significantly different from those in sh-ACC1+ C646 group (P<0.01). Conclusion: Knockdown of ACC1 promotes the migration of KYSE-450 cell by up-regulating HSP27 and increasing histone acetylation.

The value of CXorf67 and H3K27me3 for diagnosing germ cell tumors in central nervous system / 中华病理学杂志

Objective: To investigate immunohistochemical patterns of CXorf67 and H3K27me3 proteins in central nervous system germ cell tumors (GCTs) and to assess their values in both diagnosis and differential diagnosis. Methods: A total of 370 cases of central nervous system GCTs were collected from 2013 to 2020 at Huashan Hospital of Fudan University, Shanghai, China. The expression of CXorf67, H3K27me3 and commonly-used GCT markers including OCT4, PLAP, CD117, D2-40, and CD30 by immunohistochemistry (EnVision method) was examined in different subtypes of central nervous system GCTs. The sensitivity and specificity of each marker were compared by contingency table and area under receiver operating characteristic (ROC) curve. Results: Of the 370 cases there were 282 males and 88 females with a mean age of 19 years and a median age of 17 years (range, 2-57 years). Among the GCTs with germinoma, the proportions of male patients and the patients with GCT located in sellar region were both higher than those of GCTs without germinoma (P<0.05), respectively. CXorf67 was present in the nuclei of germinoma and normal germ cells, but not in other subtypes of GCT. H3K27me3 was negative in germinoma, but positive in the nuclei of surrounding normal cells and GCTs other than germinoma. In the 283 GCTs with germinoma components, the expression rate of CXorf67 was 90.5% (256/283), but no cases were positive for H3K27me3. There was also an inverse correlation between them (r2=-0.831, P<0.01). The expression rates of PLAP, OCT4, CD117 and D2-40 were 81.2% (231/283), 89.4% (253/283), 73.9% (209/283) and 88.3% (250/283), respectively. In 63 mixed GCTs with germinoma components, the expression rate of CXorf67 was 84.1% (53/63), while all cases were negative for H3K27me3. The expression rates of PLAP, OCT4, CD117 and D2-40 were 79.4% (50/63), 79.4% (50/63), 66.7% (42/63) and 87.3% (55/63), respectively. The 6 markers with largest area under ROC curve in ranking order were H3K27me3, CXorf67, D2-40, OCT4, PLAP and CD117 (P<0.05). Conclusions: CXorf67 and H3K27me3 have high sensitivity and high specificity in diagnosing germinoma. There is a significant inverse correlation between them. Therefore, they can both be used as new specific immunohistochemical markers for the diagnosis of GCTs.

Diffuse midline gliomas with H3K27 alteration in children: a clinicopathological analysis of forty-one cases / 中华病理学杂志

Objective: To investigate the clinicopathological features of pediatric diffuse midline glioma with H3K27 alteration and to analyze their relationship with prognosis. Methods: Forty-one cases of childhood diffuse midline glioma with H3K27 alteration were collected at Children's Hospital of Fudan University (39 cases) and Xi'an Children's Hospital (2 cases), from July 2016 to July 2020. The clinical manifestations, imaging data, histopathology, immunohistochemical phenotype and molecular genetics features, tumor size, site and histological grading were evaluated. Results: Among the 41 cases, 21 were males and 20 females, the age of onset was 3-14 years, the average and median age was 7.6 years and 7.0 years, respectively. The tumor sites were brain stem (n=36) and other locations (n=5). The clinical manifestations were dizziness, gait disturbance, and limb weakness, etc. The MRI features were variable. The histology varied from low-grade to high-grade glioma with neuron differentiation. Immunohistochemistry showed that the tumor cells expressed H3K27M, GFAP, and Olig2. Genetic study showed that 76% (16/21) of tumors had H3F3A gene mutation, mostly accompanied by TP53 (62%, 13/21) missense mutation; five tumors (24%, 5/21) had HIST1H3B gene mutation, accompanied by missense mutations in ACVR1 and PI3K pathway-related gene PIK3CA (4/5) and PIK3R1 (1/5) mutations. The prognosis was dismal with only one alive and others died. The average and median overall survival time was 7 months and 4 months, respectively. Cox multivariate regression analysis showed that age, tumor location, radiologically maximum tumor diameter, histologic grading, and surgical methods were not significantly associated with overall survival rate (P>0.05). Conclusions: Pediatric diffuse midline gliomas with H3K27 alteration have unique clinicopathological and genetic characteristics. The prognosis is poor. The tumor location and histopathologic grading are not related to prognosis. New specific drugs and comprehensive treatment are needed to improve the prognosis.

Histone methylation and diabetic cardiomyopathy / 生理学报

Histone methylation is one of the key post-translational modifications that plays a critical role in various heart diseases, including diabetic cardiomyopathy. A great deal of evidence has shown that histone methylation is closely related to hyperglycemia, insulin resistance, lipid and advanced glycation end products deposition, inflammatory and oxidative stress, endoplasmic reticulum stress and cell apoptosis, and these pathological factors play an important role in the pathogenesis of diabetic cardiomyopathy. In order to provide a novel theoretical basis and potential targets for the treatment of diabetic cardiomyopathy from the perspective of epigenetics, this review discussed and elucidated the association between histone methylation and the pathogenesis of diabetic cardiomyopathy in details.

Effect of CXCR4 on the Treatment Response and Prognosis of Carfilzomib in Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To explore the effect of CXCR4 on the treatment response and prognosis of Carfilzomib (CFZ) in multiple myeloma.@*METHODS@#Dataset GSE69078 based on microarray data from two CFZ-resistant MM cell lines and their corresponding parental cell lines (KMS11-KMS11/CFZ and KMS34-KMS34/CFZ) were downloaded from Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified, and Protein-protein interaction (PPI) network was established to identify the key genes involved in CFZ resistance acquisition. Finally, the prognostic roles of the CFZ risistance key genes in MM using MMRF-CoMMpass data study was verified.@*RESULTS@#44 up-regulated and 46 down-regulated DEGs were identified. Top 10 hub genes (CCND1, CXCR4, HGF, PECAM1, ID1, HEY1, TCF4, HIST1H4J, HIST1H2BD and HIST1H2BH) were identified via Protein-protein interaction (PPI) network analysis. The CoMMpass data showed that high CXCR4 expression showed correlation to relative higher relapse and progress rates and the overall survival was significant decreased in high CXCR4 patients (P=0.013).@*CONCLUSION@#CXCR4 perhaps plays a crucial role in CFZ acquired resistance, which might help identifying potential CFZ-sensitive patients before treatment and providing a new therapeutic target in CFZ-resistant MM.

CD36 gene deletion reduces muscle insulin sensitivity in mice by up-regulating PTP1B expression / 南方医科大学学报

OBJECTIVE@#To investigate the effect CD36 deficiency on muscle insulin signaling in mice fed a normal-fat diet and explore the possible mechanism.@*METHODS@#Wild-type (WT) mice and systemic CD36 knockout (CD36-/-) mice with normal feeding for 14 weeks (n=12) were subjected to insulin tolerance test (ITT) after intraperitoneal injection with insulin (1 U/kg). Real-time PCR was used to detect the mRNA expressions of insulin receptor (IR), insulin receptor substrate 1/2 (IRS1/2) and protein tyrosine phosphatase 1B (PTP1B), and Western blotting was performed to detect the protein expressions of AKT, IR, IRS1/2 and PTP1B in the muscle tissues of the mice. Tyrosine phosphorylation of IR and IRS1 and histone acetylation of PTP1B promoter in muscle tissues were detected using co-immunoprecipitation (Co-IP) and chromatin immunoprecipitation (ChIP), respectively.@*RESULTS@#CD36-/- mice showed significantly lowered insulin sensitivity with obviously decreased area under the insulin tolerance curve in comparison with the WT mice (P < 0.05). CD36-/- mice also had significantly higher serum insulin concentration and HOMA-IR than WT mice (P < 0.05). Western blotting showed that the p-AKT/AKT ratio in the muscle tissues was significantly decreased in CD36-/- mice as compared with the WT mice (P < 0.01). No significant differences were found in mRNA and protein levels of IR, IRS1 and IRS2 in the muscle tissues between WT and CD36-/- mice (P>0.05). In the muscle tissue of CD36-/- mice, tyrosine phosphorylation levels of IR and IRS1 were significantly decreased (P < 0.05), and the mRNA and protein levels of PTP1B (P < 0.05) and histone acetylation level of PTP1B promoters (P < 0.01) were significantly increased as compared with those in the WT mice. Intraperitoneal injection of claramine, a PTP1B inhibitor, effectively improved the impairment of insulin sensitivity in CD36-/- mice.@*CONCLUSION@#CD36 is essential for maintaining muscle insulin sensitivity under physiological conditions, and CD36 gene deletion in mice causes impaired insulin sensitivity by up-regulating muscle PTP1B expression, which results in detyrosine phosphorylation of IR and IRS1.