Discovery of novel FUT8 inhibitors with promising affinity and in vivo efficacy for colorectal cancer therapy.

As a member of glycosyltransferases, fucosyltransferase 8 (FUT8) is essential to core fucosylation and has been considered as a potential therapeutic target for malignant tumors, including colorectal cancer (CRC). Based on the identification of key binding residues and probable conformation of FUT8, an integrated strategy that combines virtual screening and chemical optimization was carried out and compound 15 was identified as a potent FUT8 inhibitor with novel chemical structure and in vitro antitumor activity. Moreover, chemical pulldown experiments and binding assays confirmed that compound 15 selectively bound to FUT8. In vivo, compound 15 showed promising anti-CRC effects in SW480 xenografts. These data support that compound 15 is a potential FUT8 inhibitor for CRC treatment and deserve further optimization studies.

Mitochondrial GPX4 acetylation is involved in cadmium-induced renal cell ferroptosis.

Increasing evidences demonstrate that environmental stressors are important inducers of acute kidney injury (AKI). This study aimed to investigate the impact of exposure to Cd, an environmental stressor, on renal cell ferroptosis. Transcriptomics analyses showed that arachidonic acid (ARA) metabolic pathway was disrupted in Cd-exposed mouse kidneys. Targeted metabolomics showed that renal oxidized ARA metabolites were increased in Cd-exposed mice. Renal 4-HNE, MDA, and ACSL4, were upregulated in Cd-exposed mouse kidneys. Consistent with animal experiments, the in vitro experiments showed that mitochondrial oxidized lipids were elevated in Cd-exposed HK-2 cells. Ultrastructure showed mitochondrial membrane rupture in Cd-exposed mouse kidneys. Mitochondrial cristae were accordingly reduced in Cd-exposed mouse kidneys. Mitochondrial SIRT3, an NAD+-dependent deacetylase that regulates mitochondrial protein stability, was reduced in Cd-exposed mouse kidneys. Subsequently, mitochondrial GPX4 acetylation was elevated and mitochondrial GPX4 protein was reduced in Cd-exposed mouse kidneys. Interestingly, Cd-induced mitochondrial GPX4 acetylation and renal cell ferroptosis were exacerbated in Sirt3-/- mice. Conversely, Cd-induced mitochondrial oxidized lipids were attenuated in nicotinamide mononucleotide (NMN)-pretreated HK-2 cells. Moreover, Cd-evoked mitochondrial GPX4 acetylation and renal cell ferroptosis were alleviated in NMN-pretreated mouse kidneys. These results suggest that mitochondrial GPX4 acetylation, probably caused by SIRT3 downregulation, is involved in Cd-evoked renal cell ferroptosis.

Arsenic exposure causes decline in sperm motility accompanied by energy metabolism disorders in mouse testes.

Arsenic (As) is a notorious environmental toxicant widely present in various natural environments. As exposure has been correlated with the decline in sperm motility. Yet, the mechanism has not been fully elucidated. Adult male C57 mice were given 0, 1, or 15 mg/L NaAsO2 for 10 weeks. The mature seminiferous tubules and sperm count were decreased in As-exposed mice. Sperm motility and several sperm motility parameters, including average path velocity (VAP), straight-line velocity (VSL), curvilinear velocity (VCL), beat-cross frequency (BCF), linearity (LIN), straightness (STR), and amplitude of lateral head displacement (ALH), were declined in As-exposed mice. RNA sequencing and transcriptomics analyses revealed that differentially expressed genes (DEGs) were mainly enriched in metabolic pathways. Untargeted metabolomics analyses indicated that energy metabolism was disrupted in As-exposed mouse testes. Gene set enrichment analysis showed that glycolysis and oxidative phosphorylation were disturbed in As-exposed mouse testes. As-induced disruption of testicular glucose metabolism and oxidative phosphorylation was further validated by RT-PCR and Western blotting. In conclusion, As exposure causes decline in sperm motility accompanied by energy metabolism disorders in mouse testes.

Advances in the Therapeutic Potential of Inhibitors Targeting Glycogen Synthase Kinase 3 in Inflammatory Diseases.

Glycogen synthase kinase-3 (GSK3) is one of the important serine/threonine protein kinases and has two isoforms, namely, GSK3α and GSK3ß. GSK3 inhibits glycogen synthase activity through phosphorylation. It plays a key role in various pathophysiological processes, such as differentiation, immunity, metabolism, cell death, and cell survival. Therefore, GSK3 has evolved as an important therapeutic target for treating neurological diseases, inflammatory diseases, and cancer. In addition, GSK3 regulates inflammatory processes through NF-κB-induced expression of various cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6. Moreover, GSK3 is reported to participate in many signaling pathways related to disease pathology, including PI3K/Akt, Wnt, Hedgehog, cyclic adenosine monophosphate, mitogen-activated protein kinase, and transforming growth factor-ß (TGF-ß). GSK3 has become a therapeutic target against some inflammatory diseases, including the inclusion body myositis, sepsis, and inflammatory bowel disease. Hence, several GSK3 inhibitors have been under evaluation as new therapeutic strategies in recent years. Two drugs targeting GSK3 have already entered clinical studies, including tideglusib and lithium carbonate. In this study, we analyzed nearly 30 different small-molecule GSK3 inhibitors reported in the past 4 years and classified them into four categories (thiazole, pyridine, F-substituted benzene, and others) according to their structure to conduct further literature research. Moreover, we summarized the optimal compounds and described the process of transformation from the lead compound to the optimal compound. In addition, we aimed to summarize the role of GSK3 in the pathogenesis of inflammatory diseases, with insights into the recent progress in the discovery of GSK3 inhibitors.

Discovery of Selective P2Y6R Antagonists with High Affinity and In Vivo Efficacy for Inflammatory Disease Therapy.

As a member of purinoceptors, the P2Y6 receptor (P2Y6R) plays a crucial role in modulating immune signals and has been considered as a potential therapeutic target for inflammatory diseases. On the basis of the speculated probable conformation and binding determinants of P2Y6R, a hierarchical strategy that combines virtual screening, bioassays, and chemical optimization was presented. A potent P2Y6R antagonist (compound 50) was identified to possess excellent antagonistic activity (IC50 = 5.914 nM) and high selectivity. In addition, binding assays and chemical pull-down experiments confirmed that compound 50 was nicely bound to P2Y6R. Notably, compound 50 could effectively ameliorate DSS-induced ulcerative colitis in mice through inhibiting the activation of NLRP3 inflammasome in colon tissues. Moreover, treatment with compound 50 reduced LPS-induced pulmonary edema and infiltration of inflammatory cells in mice. These findings suggest that compound 50 could serve as a specific P2Y6R antagonist for treating inflammatory diseases and deserve further optimization studies.

Mitochondria-derived reactive oxygen species are involved in renal cell ferroptosis during lipopolysaccharide-induced acute kidney injury.

Our earlier studies indicated that reactive oxygen species (ROS) were involved in lipopolysaccharide (LPS)-induced acute kidney injury (AKI). The present study aimed to explore the role of mitochondria-derived ROS on renal cell ferroptosis during LPS-induced AKI. Male CD-1 mice were intraperitoneally injected with LPS (2.0 mg/kg). Renal MDA and 4HNE residue, two markers of lipid peroxidation, were increased in LPS-exposed mice. Oxidized lipids were detected in LPS-treated human HK-2 cells. In vivo, ferroptosis-characteristic ultrastructure changes, including cell volume reduction, nuclear pyknosis and smaller mitochondria, were shown in renal cortex. In vitro, abnormal alteration of mitochondrial membrane potential was observed in LPS-treated human HK-2 cells. Ferrostatin-1, a specific inhibitor of ferroptosis, attenuated LPS-evoked renal lipid peroxidation, ferroptosis-characteristic mitochondrial damage and renal cell death. Mechanistically, mitochondria-derived ROS were elevated in LPS-stimulated HK-2 cells. MitoQ, a mitochondria-targeted antioxidant, almost completely scavenged LPS-stimulated mitochondrial ROS in human HK-2 cells. Moreover, pretreatment with MitoQ attenuated LPS-induced GSH depletion and lipid peroxidation in mouse kidney. Finally, pretreatment with MitoQ alleviated LPS-induced renal cell death and AKI. Taken together, these results suggest that mitochondria-derived ROS contribute, at least partially, to renal cell ferroptosis during LPS-induced AKI. Mitochondria-targeted antioxidants may be potential therapeutic agents for sepsis-induced AKI.

Endoplasmic reticulum stress-induced exosomal miR-27a-3p promotes immune escape in breast cancer via regulating PD-L1 expression in macrophages.

Immune escape of breast cancer cells contributes to breast cancer pathogenesis. Tumour microenvironment stresses that disrupt protein homeostasis can produce endoplasmic reticulum (ER) stress. The miRNA-mediated translational repression of mRNAs has been extensively studied in regulating immune escape and ER stress in human cancers. In this study, we identified a novel microRNA (miR)-27a-3p and investigated its mechanistic role in promoting immune evasion. The binding affinity between miR-27a-3p and MAGI2 was predicted using bioinformatic analysis and verified by dual-luciferase reporter assay. Ectopic expression and inhibition of miR-27a-3p in breast cancer cells were achieved by transduction with mimics and inhibitors. Besides, artificial modulation of MAGI2 and PTEN was done to explore their function in ER stress and immune escape of cancer cells. Of note, exosomes were derived from cancer cells and co-cultured with macrophages for mechanistic studies. The experimental data suggested that ER stress biomarkers including GRP78, PERK, ATF6, IRE1α and PD-L1 were overexpressed in breast cancer tissues relative to paracancerous tissues. Endoplasmic reticulum stress promoted exosome secretion and elevated exosomal miR-27a-3p expression. Elevation of miR-27a-3p and PD-L1 levels in macrophages was observed in response to exosomes-overexpressing miR-27a-3p in vivo and in vitro. miR-27a-3p could target and negatively regulate MAGI2, while MAGI2 down-regulated PD-L1 by up-regulating PTEN to inactivate PI3K/AKT signalling pathway. Less CD4+ , CD8+ T cells and IL-2, and T cells apoptosis were observed in response to co-culture of macrophages and CD3+ T cells. Conjointly, exosomal miR-27a-3p promotes immune evasion by up-regulating PD-L1 via MAGI2/PTEN/PI3K axis in breast cancer.

Endoplasmic reticulum stress confers 5-fluorouracil resistance in breast cancer cell via the GRP78/OCT4/lncRNA MIAT/AKT pathway.

5-Fluorouracil (5-FU) is an effective anticancer drug. However, high drug resistance limits its chemotherapeutic efficacy. Cancer cell resistance in colon cancer to 5-FU has been attributed to endoplasmic reticulum (ER) stress. But little is known about any similar role in resistance of breast cancer (BC). Here, we aim to investigate the role of ER stress played in BC cell resistance to 5-FU and to describe relevant molecular mechanisms. The expression patterns of 78-kDa glucose-regulated protein (GRP78), octamer 4 (OCT4), long non-coding RNA (lncRNA) myocardial infarction associated transcript (MIAT), and Protein kinase B (AKT) in BC MCF-7 cells resistant to 5-FU were determined by Western blot assay. Next, gain- and loss of-function experiments were conducted to verify effects of GRP78, OCT4, MIAT, and AKT on the to 5-FU sensitivity of MCF-7 cells and 5-FU resistant MCF cells (MCF-7/5-FU). Besides, the in vivo roles of the GRP78/OCT4/lncRNA MIAT/AKT pathway were assessed in tumor-bearing nude mice. 5-FU induced ER stress increased the expression of GRP78 in MCF-7 cells. GRP78 could positively regulate the expression of MIAT and AKT through upregulating OCT4, thereby contributing to 5-FU resistance in BC cells. Additionally, the function of GRP78 silencing in promoting tumor cell sensitivity was confirmed in vivo. These data supported an important role of the ER stress-mediated GRP78/OCT4/lncRNA MIAT/AKT pathway in BC cell resistance to 5-FU, highlighting potential molecular targets for combating 5-FU resistance in BC.

Simple prosthesis versus prosthesis plus titanium-coated polypropylene mesh for implant-based immediate breast reconstruction after total mastectomy for breast cancer.

BACKGROUND: Our study compares the cosmetic effects, postoperative complications, and quality of life of immediate breast reconstruction with simple prosthesis or prosthesis plus titanium-coated polypropylene mesh (TCPM) after total mastectomy for breast cancer. METHODS: In total, 69 patients who underwent total mastectomy, sentinel lymph node biopsy, and immediate prosthetic breast reconstruction from January 2015 to December 2018 in our hospital were selected, and their cosmetic effects, complications, and quality of life after reconstruction were recorded immediately after surgery and 6 months after surgery. RESULTS: Of these 69 patients, 29 were in the simple prosthesis group and 40 in the prosthesis + TCPM group. The incidence of surgical complications was 17.2% in the simple prosthesis group (5/29; including 4 cases of capsular contracture and 1 case of infection) 15.0% in the prosthesis + TCPM group (6/40; 1 case of flap necrosis, 2 cases of poor wound healing, 2 cases of hematomas, and 1 case of inadequate blood supply to nipple). The complications were successfully managed after symptomatic treatment in both groups. No prosthesis loss was noted. The incidence of postoperative complications showed there to be no significant differences between these two groups (P=0.06, χ2=0.80). The satisfaction rate of patients on cosmetic effects was 95.0% (38/40) in the prosthesis + TCPM group, significantly higher than that in the simple prosthesis group (75.90%, 22/29) (P=0.05, χ2=3.87). The quality of life in the simple prosthesis group at 2 weeks and six months after the operation was significantly lower than that in the prosthesis + TCPM group. The incidence rate of arm pain and fatigue at 2 weeks after operation was significantly higher than that in the prosthesis + TCPM group (P=0.04, χ2=4.42). The satisfaction of family life and sexual interest 6 months after the operation was also significantly lower in the simple prosthesis group than in the prosthesis + TCPM group (P=0.03, χ2=4.95). CONCLUSIONS: Breast reconstruction with prosthesis combined with TCPM does not increase surgical complications and has a good cosmetic effect and high patient satisfaction. Thus, it is a safe and reconstruction method.

The effect of laterite density on radon diffusion behavior.

Radon generated in porous media such as soils and rocks migrates into indoor and outdoor air mainly by diffusion, possessing significant hazards to human health. In order to reduce these hazards of radon, it is of great importance to study the diffusion behavior of radon. In this study, we systematically measured the radon diffusion coefficient of laterite with the density ranging from 0.917gcm-3 to 2.238gcm-3, and studied the effect of laterite density on the radon diffusion. The results show that the radon diffusion coefficient of the laterite generally decreases with the increasing laterite density. In addition, three possible relationships between the radon diffusion coefficient and the laterite density are found out as follows: (1) the linear correlation with a slope of -4.48 × 10-6 for laterite with density ranging from 0.917 to 1.095gcm-3, (2) the exponential correlation for laterite with density from 1.095 to 1.63gcm-3, (3) linear correlation with a slope of -3.1 × 10-7 for laterite with density from 1.63 to 2.238gcm-3. The complex relationship between the radon diffusion coefficient and density is caused by the change of porosity and tortuosity of the laterite. Therefore, we suggest that a suitable density should be adopted while using the laterite to effectively cover uranium tailings or economically produce building materials that can curb the radon exhalation.

Nanoassemblies constructed from bimodal mesoporous silica nanoparticles and surface-coated multilayer pH-responsive polymer for controlled delivery of ibuprofen.

The pH-sensitive poly(D-A) grafted amine-functionalized bimodal mesoporous silica (D-A/BMMs) was prepared by a facile method used as a drug delivery vehicle. They exhibited superior properties such as good dispersion in aqueous medium, high drug loading efficiency, improved stability and high drug release rates. Meanwhile, its structural features and performances in a controlled delivery of ibuprofen (IBU) were systematically investigated by using XRD, N2 adsorption and desorption, SEM, TEM, FT-IR, elemental analysis and TG techniques. The results demonstrated that the obtained nanocomposite presented a flexible control over drug release by controlling the grafting amount of D-A onto the mesopores surface of aminated BMMs. The cumulative percent release of IBU from D-A/BMMs was found to be much higher at pH 7.4 than at pH 2.0. The release rate was very slow in an acidic medium but became faster in a neutral medium, owing to hydrogen bonding in an acidic medium and electrostatic repulsion between negatively charged carboxyl groups in an alkaline medium.