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Backgound: Colorectal cancer (CRC) is a complex, multistep disease that arises from the interplay genetic mutations and epigenetic alterations. The histone H3K36 trimethyltransferase SET domain‐containing 2 (SETD2), as an epigenetic signalling molecule, has a 5% mutation rate in CRC. SETD2 expression is decreased in the development of human CRC and mice treated with Azoxymethane /Dextran sodium sulfate (AOM/DSS). Loss of SETD2 promoted CRC development. SMAD Family member 4 (SMAD4) has a 14% mutation rate in CRC, and SMAD4 ablation leads to CRC. The co‐mutation of SETD2 and SMAD4 predicted advanced CRC. However, little is known on the potential synergistic effect of SETD2 and SMAD4. Methods: CRC tissues from mice and SW620 cells were used as research subjects. Clinical databases of CRC patients were analyzed to investigate the association between SETD2 and SMAD4. SETD2 and SMAD4 double‐knockout mice were established to further investigate the role of SETD2 in SMAD4‐deficient CRC. The intestinal epithelial cells (IECs) were isolated for RNA sequencing and chromatin immunoprecipitation sequencing (ChIP‐seq) to explore the mechanism and the key molecules resulting in CRC. Molecular and cellular experiments were conducted to analyze the role of SETD2 in SMAD4‐deficient CRC. Finally, rescue experiments were performed to confirm the molecular mechanism of SETD2 in the development of SMAD4‐dificient CRC. Results: The deletion of SETD2 promotes the malignant progression of SMAD4‐deficient CRC. Smad4Vil‐KO; Setd2Vil‐KO mice developed a more severe CRC phenotype after AOM/DSS induction, with a larger tumour size and a more vigorous epithelial proliferation rate. Further mechanistic findings revealed that the loss of SETD2 resulted in the down‐regulation of DUSP7, which is involved in the inhibition of the RAS/ERK signalling pathway. Finally, the ERK1/2 inhibitor SCH772984 significantly attenuated the progression of CRC in Smad4Vil‐KO;Setd2Vil‐KO mice, and overexpression of DUSP7 significantly inhibited the proliferation rates of SETD2KO; SMAD4KO SW620 cells. Conclusions: Our results demonstrated that SETD2 inhibits the RAS/ERK signaling pathway by facilitating the transcription of DUSP7 in SMAD4‐deficient CRC, which could provide a potential therapeutic target for the treatment of advanced CRC. [ABSTRACT FROM AUTHOR]

Background: Renal fibrosis is the final development pathway and the most common pathological manifestation of chronic kidney disease. Epigenetic alteration is a significant intrinsic factor contributing to the development of renal fibrosis. SET domain‐containing 2 (SETD2) is the sole histone H3K36 trimethyltransferase, catalysing H3K36 trimethylation. There is evidence that SETD2‐mediated epigenetic alterations are implicated in many diseases. However, it is unclear what role SETD2 plays in the development of renal fibrosis. Methods: Kidney tissues from mice as well as HK2 cells were used as research subjects. Clinical databases of patients with renal fibrosis were analysed to investigate whether SETD2 expression is reduced in the occurrence of renal fibrosis. SETD2 and Von Hippel–Lindau (VHL) double‐knockout mice were used to further investigate the role of SETD2 in renal fibrosis. Renal tubular epithelial cells isolated from mice were used for RNA sequencing and chromatin immunoprecipitation sequencing to search for molecular signalling pathways and key molecules leading to renal fibrosis in mice. Molecular and cell biology experiments were conducted to analyse and validate the role of SETD2 in the development of renal fibrosis. Finally, rescue experiments were performed to determine the molecular mechanism of SETD2 deficiency in the development of renal fibrosis. Results: SETD2 deficiency leads to severe renal fibrosis in VHL‐deficient mice. Mechanically, SETD2 maintains the transcriptional level of Smad7, a negative feedback factor of the transforming growth factor‐β (TGF‐β)/Smad signalling pathway, thereby preventing the activation of the TGF‐β/Smad signalling pathway. Deletion of SETD2 leads to reduced Smad7 expression, which results in activation of the TGF‐β/Smad signalling pathway and ultimately renal fibrosis in the absence of VHL. Conclusions: Our findings reveal the role of SETD2‐mediated H3K36me3 of Smad7 in regulating the TGF‐β/Smad signalling pathway in renal fibrogenesis and provide an innovative insight into SETD2 as a potential therapeutic target for the treatment of renal fibrosis. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the efficiency of our chemically synthesized TT-00420, a novel spectrum-selective multiple protein kinase inhibitor, in cultured cells and animal models of gallbladder cancer (GBC) and explore its potential mechanism. Methods: Multiple GBC models were established to assess the anti-tumor efficiency, toxicity, and pharmacokinetics of TT-00420. Integrated transcriptomic, proteomic and phosphoproteomic analysis was conducted to identify potential downstream effectors of TT-00420. Western blotting, qRT-PCR, nuclear-cytoplasm separation, and immunofluorescence were performed to confirm the multi-omic results and explore the molecular mechanism of TT-00420. Immunohistochemistry was used to detect FGFR1 and p-FGFR1 expression levels in GBC samples. Autodock software was utilized to investigate the potential binding mode between the TT-00420 and the human FGFR1. Results: We found that TT-00420 exerted potent growth inhibition of GBC cell lines and multiple xenograft models. Treatment of mice with 15 mg/kg TT-00420 via gavage displayed a half-life of 1.8 h in the blood and rapid distribution to the liver, kidneys, lungs, spleen, and tumors at 0.25 h, but no toxicity to these organs over 2 weeks. Multi-omic analysis revealed c-Jun as a potential downstream effector after TT-00420 treatment. Mechanistically, TT-00420 showed rigorous ability to block FGFR1 and its downstream JNK-JUN (S63/S73) signaling pathway, and induce c-Jun S243-dependent MEK/ERK reactivation, leading to FASLG-dependent tumor cell death. Finally, we found that FGFR1 and p-FGFR1 expression was elevated in GBC patients and these levels correlated with decreased patient survival. Conclusions: TT-00420 shows potent antitumor efficacy and may serve as a novel agent to improve GBC prognosis. [ABSTRACT FROM AUTHOR]

Introduction: This study investigates the synergistic effect of TGF‐β1 and Nrp‐1 on CD4+CD25+ Tregs' stabilization, and the associated pathways of signal transduction, in vitro models in the presence of LPS. Materials and Methods: Spleen CD4+CD25+ Tregs cells of mice models in the presence of LPS, were transfected with an shRNA targeting Nrp‐1, Smad2, or Smad3, may or may not be treated with recombinant TGF‐β1. Followed by subsequent determination of cellular proliferation, rate of apoptosis, observation of the Foxp3, CTLA‐4, and TGF‐β1m+ expression levels, foxp3‐TSDR methylation, secretion levels of the inhibitory cytokines IL‐10 and TGF‐β1, and Smad2/3 of CD4+CD25+ Tregs expression. Results: A remarkable stimulation in CD4+CD25+ Tregs' stability is noted after administering recombinant TGF‐β1 in the presence of LPS, and promoted cellular viability, increased Foxp3, CTLA‐4, and TGF‐β1m+ expression, and elevated secretion of IL‐10 and TGF‐β1. This also inhibited the apoptosis and methylation of foxp3‐ TSDR of CD4+CD25+ Tregs. The shRNA transfection silenced Nrp‐1 and Smad3, but not Smad2, resulting in the suppression of the recombinant TGF‐β1‐mediated effects in the presence of LPS. Conclusions: According to the results, Nrp‐1 mediates TGF‐β1 to improve the stability of regulatory CD4+CD25+ T cells and maybe a possible therapeutic target with the ability to improve the CD4+CD25+ Tregs associated negative immunoregulation that is related to the TGF‐β1/Smads cell signaling during sepsis. [ABSTRACT FROM AUTHOR]

Bone loss due to smoking represents a major risk factor for fractures and bone osteoporosis. Signaling through the aryl hydrocarbon receptor (AhR) and its ligands contributes to both bone homeostasis and inflammatory diseases. It remains unclear whether the same AhR signaling axis affects the temporomandibular joint (TMJ). The aim of this study was to investigate possible mechanisms which mediate bone loss in the TMJ due to smoking. In particular, whether benzo[a]pyrene (B[a]P), a carcinogen of tobacco smoke, induces expression of the AhR target gene, Cyp1a1, in mandibular condyles. Possible functions of an endogenous ligand of FICZ, were also investigated in a TMJ-osteoarthritis (OA) mouse model. B[a]P was administered orally to wild-type and AhR−/− mice and bone metabolism was subsequently examined. TMJ-OA was induced in wild-type mice with forceful opening of the mouth. Therapeutic functions of FICZ were detected with μCT and histology. Exposure to B[a]P accelerated bone loss in the mandibular subchondral bone. This bone loss manifested with osteoclastic bone resorption and upregulated expression of Cyp1a1 in an AhR-dependent manner. In a mouse model of TMJ-OA, FICZ exhibited a dose-dependent rescue of mandibular subchondral bone loss by repressing osteoclast activity. Meanwhile, in vitro, pre-treatment with FICZ reduced RANKL-mediated osteoclastogenesis. B[a]P regulates mandibular subchondral bone metabolism via the Cyp1a1. The AhR ligand, FICZ, can prevent TMJ-OA by regulating osteoclast differentiation. [ABSTRACT FROM AUTHOR]

Background and Purpose: Chloroquine is a traditional medicine to treat malaria. There is increasing evidence that chloroquine not only induces phagocytosis but regulates vascular tone. Few reports investigating the effect of chloroquine on vascular responsiveness of coronary arteries have been made. In this study, we examined how chloroquine affected endothelium-dependent relaxation in coronary arteries under normal and diabetic conditions.Experimental Approach: We isolated coronary arteries from mice and examined endothelium-dependent relaxation (EDR). Human coronary endothelial cells and mouse coronary endothelial cells isolated from control and diabetic mouse (TALLYHO/Jng [TH] mice, a spontaneous type 2 diabetic mouse model) were used for the molecular biological or cytosolic NO and Ca2+ measurements.Key Results: Chloroquine inhibited endothelium-derived NO-dependent relaxation but had negligible effect on endothelium-derived hyperpolarization (EDH)-dependent relaxation in coronary arteries of control mice. Chloroquine significantly decreased NO production in control human coronary endothelial cells partly by phosphorylating eNOSThr495 (an inhibitory phosphorylation site of eNOS) and attenuating the rise of cytosolic Ca2+ concentration after stimulation. EDR was significantly inhibited in diabetic mice in comparison to control mice. Interestingly, chloroquine enhanced EDR in diabetic coronary arteries by, specifically, increasing EDH-dependent relaxation due partly to its augmenting effect on gap junction activity in diabetic mouse coronary endothelial cells.Conclusions and Implications: These data indicate that chloroquine affects vascular relaxation differently under normal and diabetic conditions. Therefore, the patients' health condition such as coronary macrovascular or microvascular disease, with or without diabetes, must be taken account into the consideration when selecting chloroquine for the treatment of malaria. [ABSTRACT FROM AUTHOR]

Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is an RNA-binding protein that regulates multiple biological processes, including paraspeckles formation and cellular signal transduction. Recently, hnRNPK has been shown to interact with SINE-derived nuclear RNA localization (SIRLOIN)-containing RNAs, and orchestrate nuclear enrichment and cellular functions of long noncoding RNAs (lncRNAs). hnRNPK–lncRNAs interaction is potentially implicated in various pathogenic disorders including tumorigenesis, and Kabuki-like, Au-Kline, and Okamoto syndromes. [ABSTRACT FROM AUTHOR]

Postmenopausal osteoporosis (PMO) is a progressive bone disease characterized by the over‐production and activation of osteoclasts in elderly women. In our study, we investigated the anti‐osteoclastogenic effect of evodiamine (EVO) in vivo and in vitro, as well as the underlying mechanism. By using an in vitro bone marrow macrophage (BMM)‐derived osteoclast culture system, we found that EVO inhibited osteoclast formation, hydroxyapatite resorption and receptor activator of NF‐κB ligand (RANKL)‐induced osteoclast marker gene and protein expression. Mechanistically, we found that EVO inhibited the degradation and RANKL‐induced transcriptional activity of IκBα. RANKL‐induced Ca2+ oscillations were also abrogated by EVO. In vivo, an ovariectomized (OVX) mouse model was established to mimic PMO, and OVX mice received oral administration of either EVO (10 mg/kg) or saline every other day. We found that EVO can attenuate bone loss in OVX mice by inhibiting osteoclastogenesis. Taken together, our findings suggest that EVO suppresses RANKL‐induced osteoclastogenesis through NF‐κB and calcium signalling pathways and has potential value as a therapeutic agent for PMO. [ABSTRACT FROM AUTHOR]

A delicate balance between osteoblastic bone formation and osteoclastic bone resorption is crucial for bone homeostasis. This process is regulated by the Hippo signaling pathway including key regulatory molecules RASSF2, NF2, MST1/2, SAV1, LATS1/2, MOB1, YAP, and TAZ. It is well established that the Hippo signaling pathway plays an important part in regulating osteoblast differentiation, but its role in osteoclast formation and activation remains poorly understood. In this review, we discuss the emerging role of Hippo‐signaling pathway in osteoclast formation and bone homeostasis. It is revealed that specific molecules of the Hippo‐signaling pathway take part in a stage specific regulation in pre‐osteoclast proliferation, osteoclast differentiation and osteoclast apoptosis and survival. Upon activation, MST and LAST, transcriptional co‐activators YAP and TAZ bind to the members of the TEA domain (TEAD) family transcription factors, and influence osteoclast differentiation via regulating the expression of downstream target genes such as connective tissue growth factor (CTGF/CCN2) and cysteine‐rich protein 61 (CYR61/CCN1). In addition, through interacting or cross talking with RANKL‐mediated signaling cascades including NF‐κB, MAPKs, AP1, and NFATc1, Hippo‐signaling molecules such as YAP/TAZ/TEAD complex, RASSF2, MST2, and Ajuba could also potentially modulate osteoclast differentiation and function. Elucidating the roles of the Hippo‐signaling pathway in osteoclast development and specific molecules involved is important for understanding the mechanism of bone homeostasis and diseases. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is a well-known endocrine disruptor, widely used in various consumer products and ubiquitously found in air, water, food, dust, and sewage leachates. Recently, several countries have restricted the use of BPA and replaced them with bisphenol S (BPS) and bisphenol F (BPF), which have a similar chemical structure to BPA. Compared to BPA, both BPS and BPF have weaker estrogenic effects, but their effects on human reproductive function including endometrial receptivity and embryo implantation still remain largely unknown. We used an in vitro spheroid (blastocyst surrogate) co-culture assay to investigate the effects of BPA, BPS, and BPF on spheroid attachment on human endometrial epithelial cells, and further delineated their role on steroid hormone receptor expression. We also used transcriptomics to investigate the effects of BPA, BPS, and BPF on the transcriptome of human endometrial cells. We found that bisphenol treatment in human endometrial Ishikawa cells altered estrogen receptor alpha (ERα) signaling and upregulated progesterone receptors (PR). Bisphenols suppressed spheroid attachment onto Ishikawa cells, which was reversed by the downregulation of PR through PR siRNA. Overall, we found that bisphenol compounds can affect human endometrial epithelial cell receptivity through the modulation of steroid hormone receptor function leading to impaired embryo implantation. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is the fifth most common cancer and the second leading cause of cancer death globally. SETD2 is a histone methyltransferase catalyzing tri-methylation of H3K36 (H3K36me3) and has been shown to participate in diverse biological processes and human tumors. However, the mechanism of SETD2 in GC remains unclear. Here, we reported that Setd2 deficiency predicts poor prognosis of gastric cancer. SETD2 loss facilitated H. felis/MNU and c-Myc-induced gastric tumorigenesis, respectively. The mouse model of stomach-specific Setd2 depletion together with c-MYC overexpression (AMS) developed high-grade epithelial defects, intestinal metaplasia and dysplasia at only 10–12 weeks of age. Mechanistically, Setd2 depletion resulted in impaired epigenetic regulation of Sirt1, thus inhibiting the SIRT1/FOXO pathway. Moreover, the agonists of FOXO signaling or overexpression of SIRT1 significantly rescued the enhanced cell proliferation and migration caused by Setd2 deficiency in SGC7901 cells. Together, our findings highlight an epigenetic mechanism by which SETD2 regulates gastric tumorigenesis through SIRT1/FOXO pathway. It may also pave the way for the development of targeted, patient-tailored therapies for GC patients with Setd2 deficiency. • Setd2 deficiency facilitates the H. felis/MNU and c-Myc-induced gastric tumorigenesis, respectively. • Loss of Setd2 promotes gastric tumorigenesis through inhibiting the SIRT1/FOXO signaling pathway. • Setd2 regulates the FOXO signaling pathway through epigenetic regulation of the Sirt1 locus. • Our work opens therapeutic opportunities for GC patients with Setd2 loss/mutations by targeting the SIRT1/FOXO signaling. [ABSTRACT FROM AUTHOR]