Sonodynamic therapy (SDT) is a noninvasive ultrasound-triggered therapeutic strategy for site-specific treatment of tumors with great depth penetration. The design of nano-sonosensitizers suitable for SDT treatment of bladder cancer (BCa) post-intravesical instillation has not yet been reported. Herein, a transmucosal oxygen-self-production SDT nanoplatform is developed to achieve highly efficient SDT against BCa. In this system, fluorinated chitosan (FCS) is synthesized as a highly effective nontoxic transmucosal delivery carrier to assemble with meso-tetra(4-carboxyphenyl)porphineconjugated catalase (CAT-TCPP). The formed CAT-TCPP/ FCS nanoparticles after intravesical instillation into the bladder cavity exhibit excellent transmucosal and intratumoral penetration capacities and could efficiently relieve hypoxia in tumor tissues by the catalase-catalyzed O 2 generation from tumor endogenous H 2 O 2 to further improve the therapeutic efficacy of SDT to ablate orthotopic bladder tumors under ultrasound. Our work presents a nano-sonosensitizer formulation with FCS to enhance transmucosal delivery and intratumoral diffusion and CAT to improve tumor oxygenation, promising for instillation-based SDT to treat bladder tumors without the concern of systemic toxicity.
Transcriptional repressor activating transcription factor 3 (ATF3) is induced by various stress stimuli, including inflammation-induced renal injury. In addition, ATF3 also down-regulates adhesion molecules like intercellular adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), and monocyte chemotactic protein-1 (MCP-1). However, the relation between up-regulated ATF3 after renal ischemia/reperfusion (I/R) injury and MCP-1 is not completely understood. In this study, we demonstrated that, in renal I/R induced inflammation, induction of adhesion molecules (interleukin-6, P-selectin, E-selectin, ICAM, VCAM, and MCP-1) was higher in ATF3-knockout mice than in wild-type animals. Molecular and biochemical analyses revealed that ATF3 binds to the ATF/CRE sites in the MCP-1 promoter and inhibits the secretion of MCP-1 from renal epithelial cells after I/R injury. Urinary exosome containing ATF3 RNA was 60-fold higher in patients with acute kidney injury than in normal controls, but no difference in total urinary ATF3 RNA levels was found. In addition, in vitro study showed that exosome containing ATF3 RNA derived from epithelial cells also inhibits MCP-1 expression in the epithelial cells and macrophage migration. Furthermore, direct administration of the epithelium-derived exosomal ATF3 RNA attenuates I/R induced kidney injury. Together, our studies reveal a novel regulatory mechanism of MCP-1 expression mediated by the exosomal ATF3 RNA under renal I/R insult and suggest a potential targeted therapy for I/R induced acute kidney injury.
hsa-miR-195-5p (miR-195) has been proven to be a critical regulator in the progression of prostate cancer (PCa). To identify additional targets and molecular functions of miR-195, we overexpressed miR-195 by transient oligonucleotide transfection in DU145 and LNCaP cells and examined the effects. RNA-based microarray and dual-luciferase assays were carried out to identify novel targets of miR-195, while in vitro functional assays, a subcutaneous xenograft model, tissue microarray (TMA) analysis and a cohort of publicly available data (Taylor cohort) were used to investigate the biological function and clinical value of miR-195 targeting. The results shown that miR-195 overexpression could markedly suppress cellular proliferation and tube formation compared with miR-negative control. The RNA-based microarray identified a total of 153 differentially regulated genes with fold changes of ≤|1.5|, including 138 (90.2%) downregulated and 15 (9.8%) upregulated genes. Among the downregulated genes, we found that proline-rich protein 11 (PRR11) combined with miR-195 expression (miR-195/PRR11) could be used as an independent predictor of the risk of biochemical recurrence in the Taylor cohort. Additionally, the dual-luciferase assay identified PRR11 as a novel target of miR-195, and the in vitro assays indicated that PRR11 abrogated the suppressive effects of miR-195 on cell proliferation, tube formation and cell cycling. Furthermore, the subcutaneous tumor xenograft model indicated that knockdown of PRR11 inhibited xenograft growth and angiogenesis, while the results of the TMA and Taylor cohort analyses collectively demonstrated that PRR11 expression was upregulated in aggressive tumors and is associated with poor clinical outcome. Taken together, these findings further illustrate the suppressive role of miR-195 in PCa, and indicate a novel role of PRR11 in PCa. Importantly, the newly identified miR-195/PRR11 axis may aid with identifying potential therapeutic targets in PCa.
Background: Diabetic nephropathy (DN) is a severe complication of diabetes with type 1 and 2. Long non-coding RNAs (lncRNAs) are being found to be involved in the DN pathogenesis. In this study, we aimed to further explore the effect and underlying mechanism of plasmacytoma variant translocation 1 (PVT1) in DN pathogenesis. Methods: The expression levels of PVT1, miR-23b-3p, and Wilms tumor protein 1 (WT1) mRNA were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot analysis was performed to determine protein expression. Cell proliferation was detected using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetr-azolium (MTS) assay. The targeted correlation between miR-23b-3p and PVT1 or WT1 was verified by dual-luciferase reporter assay. Results: PVT1 and WT1 were highly expressed in the serum of DN patients and high glucose (HG)-induced mesangial cells (MCs). The knockdown of PVT1 or WT1 ameliorated HG-induced proliferation and fibrosis in MCs. Mechanistically, PVT1 modulated WT1 expression through acting as a molecular sponge of miR-23b-3p. The miR-23b-3p/WT1 axis mediated the protective effect of PVT1 knockdown on HG-induced proliferation and fibrosis in MCs. The NF-κB pathway was involved in the regulatory network of the PVT1/miR-23b-3p/WT1 axis in HG-induced MCs. Conclusion: Our study suggested that PVT1 knockdown ameliorated HG-induced proliferation and fibrosis in MCs at least partially by regulating the miR-23b-3p/WT1/NF-κB pathway. Targeting PVT1 might be a potential therapeutic strategy for DN treatment.
BackgroundThe methylation of lysine residues has been involved in the multiple biological and diseases processes. Recently, some particular non‐histone proteins have been elucidated to be methylated by SMYD2, a SET and MYND domain protein with lysine methyltransferase activity.MethodsSMYD2 was evaluated in synovial tissue and cells derived from rheumatoid arthritis patients. We confirmed TRAF2 could be methylated by SMYD2 using Mass spectrometry, pull‐down, immunoprecipitation, methyltransferase assay, ubiquitination assay, luciferase reporter assays, and western blot analyses. Using loss‐ and gain‐of function studies, we explored the biological functions of SMYD2 in vitro and in vivo. Using acute and chronic inflammation with different mice models to determine the impact of SMYD2.ResultsHere, we first time confirmed that the cytoplasmic protein TRAF2 as the kernel node for NF‐κB signaling pathway could be methylated by SMYD2. SMYD2‐mediated TRAF2 methylation contributed to the durative sensitization of NF‐κB signaling transduction through restraining its own proteolysis and enhancing the activity. In addition, we found knocking down of SMYD2 has different degrees of mitigation in acute and chronic inflammation mice models. Furthermore, as the lysine‐specific demethylase, LSD1 could resist methylation on TRAF2 induced by SMYD2.ConclusionsOur data uncovered an unprecedented cytoplasmic protein network that employed methylation of TRAF2 for the maintenance of NF‐κB activation during inflammatory diseases.
Background Neuron apoptosis is a pivotal process for brain damage in cerebral ischemia. Dot1L (disruptor of telomeric silencing 1‐like) is only known histone H3K79 methyltransferase. It is not clear whether the role and mechanism of Dot1L on cerebral ischemia is related to regulate neuron apoptosis. Methods and Results We use a combination of mice middle cerebral artery occlusion stroke and neurons exposed to oxygen‐glucose deprivation followed by reoxygenation to investigate the role and mechanism of Dot1L on cerebral ischemia. We find knockdown or inhibition of Dot1L reversed ischemia‐induced neuronal apoptosis and attenuated the neurons injury treated by oxygen‐glucose deprivation followed by reoxygenation. Further, blockade of Dot1L prevents RIPK1 (receptor‐interacting protein kinase 1)‐dependent apoptosis through increased RIPK1 K63‐ubiquitylation and decreased formation of RIPK1/Caspase 8 complexes. In line with this, H3K79me3 enrichment in the promoter region of deubiquitin‐modifying enzyme A20 and deubiquitinase cylindromatosis gene promotes the increasing expression in oxygen‐glucose deprivation followed by reoxygenation ‐induced neuronal cells, on the contrary, oxygen‐glucose deprivation followed by reoxygenation decreases H3K79me3 level in the promoter region of ubiquitin‐modifying enzyme cIAP1 (cellular inhibitors of apoptosis proteins), and both these factors ultimately cause K63‐deubiquitination of RIPK1. Importantly, knockdown or inhibition of Dot1L in vivo attenuates apoptosis in middle cerebral artery occlusion mice and reduces the extent of middle cerebral artery occlusion ‐induced brain injury. Conclusions These data support for the first time, to our knowledge, that Dot1L regulating RIPK1 to the apoptotic death trigger contributes to cerebral ischemia injury. Therefore, targeting Dot1L serves as a new therapeutic strategy for ischemia stroke.
Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with increasing occurrence, high death rates, and unfavorable treatment regimens. The pathogenesis underlying IPF is complex and the epigenetic contributions to IPF are largely unknown. Recent studies have shown that DOT1L (Disruptor of telomeric silencing-1 like), a histone H3K79 methyltransferase, contributes to fibrosis response, but its role in IPF remains unclear. DOT1L, H3K79me3, and the profibrotic proteins levels were upregulated in the pulmonary fibrosis models both in vivo and in vitro. Lentivirus-mediated DOT1L knockdown or DOT1L-specific inhibitor EPZ5676 alleviated the pathogenesis of bleomycin-induced mouse pulmonary fibrosis. Furthermore, heterozygous DOT1L-deficient mice (Dot1l+/−) showed less sensitive to pulmonary fibrosis, as shown by decreased lung fibrosis phenotypes in vivo. Mechanically, DOT1L regulated TGF-β1-induced fibroblasts fibrosis by increasing enrichments of H3K79me3 on the promoter of Jag1 gene (encoding the Notch ligand Jagged1), enhancing the expression of Jagged1, which in turn stimulated exuberant Notch signaling and actuated the fibrosis response. In conclusion, our study confirmed DOT1L to be an epigenetic modifier in the pathogenesis of lung fibrosis, revealed a counterbalancing mechanism governing Jag1 transcription by modulating H3K79 trimethylation at the Jag1 promoter, activating the Notch signaling, and affecting the expression of profibrotic proteins to accelerate the lung fibrosis.
Background The blood‐brain barrier (BBB) plays a principal role in the healthy and diseased central nervous systems, and BBB disruption after ischaemic stroke is responsible for increased mortality. Smyd2, a member of the SMYD‐methyltransferase family, plays a vital role in disease by methylation of diverse substrates; however, little is known about its role in the pathophysiology of the brain in response to ischaemia‐reperfusion injury. Methods Using oxygen glucose deprivation and reoxygenation (OGD/R)‐induced primary brain microvascular endothelial cells (BMECs) and Smyd2 knockdown mice subjected to middle cerebral artery occlusion, we evaluated the role of Smyd2 in BBB disruption. We performed loss‐of‐function and gain‐of‐function studies to investigate the biological function of Smyd2 in ischaemic stroke. Results We found that Smyd2 was a critical factor for regulating brain endothelial barrier integrity in ischaemia‐reperfusion injury. Smyd2 is upregulated in peri‐ischaemic brains, leading to BBB disruption via methylation‐mediated Sphk/S1PR. Knockdown of Smyd2 in mice reduces BBB permeability and improves functional recovery. Using OGD/R‐induced BMECs, we demonstrated that Sphk/S1PR methylation modification by Smyd2 affects ubiquitin‐dependent degradation and protein stability, which may disrupt endothelial integrity. Moreover, overexpression of Smyd2 can damage endothelial integrity through Sphk/S1PR signalling. Conclusions Overall, these results reveal a novel role for Smyd2 in BBB disruption in ischaemic stroke, suggesting that Smyd2 may represent a new therapeutic target for ischaemic stroke.
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