Application of Mesoporous Carbon-Based Highly Dispersed K-O2 Strong Lewis Base in the Efficient Catalysis of Methanol and Ethylene Carbonate.

As an atom-economical reaction, the direct generation of dimethyl carbonate (DMC) and ethylene glycol (EG) via the transesterification of CH3OH and ethylene carbonate (EC) has several promising applications, but the exploration of carriers with high specific surface areas and novel heterogeneous catalysts with more basic sites remains a long-standing research challenge. For this purpose, herein, a nitrogen-doped mesoporous carbon (NMC, 439 m2/g) based K-O2 Lewis base catalyst (K-O2/NMC) with well-dispersed strongly basic sites (2.23 mmol/g, 84.5%) was designed and synthesized. The compositions and structures of NMC and K-O2/NMC were comprehensively investigated via Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption, CO2 temperature-programmed desorption, and contact angle measurements. The optimal structural configuration and electron cloud distribution of the K-O2/NMC catalyst were simulated using first-principles calculations. The electron transfer predominantly manifested as a flow from K-O to C-O/C-N, and the interatomic interactions between each atom were enhanced and exhibited a tendency for a more stable state after redistribution. Furthermore, the adsorption energies (Eads) of CH3OH at K-O-O and K-O-N sites were -1.4185 eV and -1.3377 eV, respectively, and the O atom in CH3OH exhibited a stronger adsorption tendency for the K atom at the K-O-O site. Under the optimal conditions, the EC conversion, DMC/EG selectivity, and turnover number/frequency were 80.9%, 98.6%/99.4%, and 40.5/60.8 h-1, respectively, with a reaction rate constant (k) of 0.1005 mol/(L·min). Results showed that the heterogeneous K-O2/NMC catalyst prepared herein greatly reduced the reaction cost while guaranteeing the catalytic effect, and the whole system required a lower reaction temperature (65 °C), a shorter reaction time (40 min), and a lower catalyst amount (2.0 wt % of EC). Therefore, K-O2/NMC can be used as a catalyst in different transesterification reactions.

Research progress on the protective effect of hormones and hormone drugs in myocardial ischemia-reperfusion injury.

Ischemic heart disease (IHD) is a condition where the heart muscle does not receive enough blood flow, leading to cardiac dysfunction. Restoring blood flow to the coronary artery is an effective clinical therapy for myocardial ischemia. This strategy helps lower the size of the myocardial infarction and improves the prognosis of patients. Nevertheless, if the disrupted blood flow to the heart muscle is restored within a specific timeframe, it leads to more severe harm to the previously deprived heart tissue. This condition is referred to as myocardial ischemia/reperfusion injury (MIRI). Until now, there is a dearth of efficacious strategies to prevent and manage MIRI. Hormones are specialized substances that are produced directly into the circulation by endocrine organs or tissues in humans and animals, and they have particular effects on the body. Hormonal medications utilize human or animal hormones as their active components, encompassing sex hormones, adrenaline medications, thyroid hormone medications, and others. While several studies have examined the preventive properties of different endocrine hormones, such as estrogen and hormone analogs, on myocardial injury caused by ischemia-reperfusion, there are other hormone analogs whose mechanisms of action remain unexplained and whose safety cannot be assured. The current study is on hormones and hormone medications, elucidating the mechanism of hormone pharmaceuticals and emphasizing the cardioprotective effects of different endocrine hormones. It aims to provide guidance for the therapeutic use of drugs and offer direction for the examination of MIRI in clinical therapy.

Exposure of nonylphenol promoted NLRP3 inflammasome and GSDMD-mediated pyroptosis in allergic rhinitis mice.

Studies have confirmed that the intake of nonylphenol (NP) can increase nasal symptoms, eosinophils, and Th2 responses in allergic rhinitis (AR) mice. However, the molecular mechanism of NP exacerbating AR inflammatory response remains unclear. Recent data suggest that NOD-like receptor 3 (NLRP3) inflammasome-mediated pyroptosis contributes to AR development. To investigate the effects of NP on NLRP3 inflammasomes and pyroptosis, an AR mouse model induced by ovalbumin (OVA) was established and treated with 0.5 mg/kg/d NP every other day. Nasal symptoms were evaluated after the final OVA instillation. Mast cells and Eosinophils in the nasal mucosa were observed using toluidine blue and Sirius red staining, respectively. The levels of NLRP3, Caspase-1, ASC, phospho-nuclear factor kappa B (NF-κB) p65, interleukin (IL)-6, TNF-α, IL-18, GSDMD and IL-1ß, were assessed by using immunohistochemical staining, ELISA, quantitative real-time PCR, or Western blot. Exposure to NP aggravates AR symptoms and promotes eosinophils, mast cells, and inflammatory factors release, along with significantly increased of NF-κB, NLRP3, Caspase-1, ASC, and GSDMD. It was concluded that NP exposure promotes NLRP3 inflammasome and GSDMD-mediated pyroptosis of the nasal mucosa. Targeted of NLRP3 and GSDMD-mediated pyroptosis may be a novel therapeutic strategy for AR exposed to NP.

MAGP1 maintains tumorigenicity and angiogenesis of laryngeal cancer by activating Wnt/ß-catenin/MMP7 pathway.

Microfibril-associated glycoprotein-1 (MAGP1), a crucial extracellular matrix protein, contributes to the initiation and progression of different cancers. However, the role of MAGP1 in laryngeal cancer is not clear. The purpose of this study was to investigate the clinical significance and biological function of MAGP1 in laryngeal cancer. MAGP1 was upregulated in public databases and laryngeal cancer tissues, and high MAGP1 expression led to a poor prognosis and was identified as an independent prognostic marker. Knocking-down MAGP1 inhibited laryngeal cancer cell growth and metastasis. According to gene set enrichment analysis, high MAGP1 expression revealed enrichment in Wnt/ß-catenin signaling and knocking-down MAGP1 in laryngeal cancer cells also caused degradation, de-activation, re-location and loss of stability of ß-catenin. Additionally, we observed MAGP1 in laryngeal cancer cells inhibits angiogenesis in an MMP7-dependent way. In conclusion, our study suggests a clinical role of MAGP1 in laryngeal cancer, signifying its potential as a therapeutic target in the future.

Ultrasound-assisted enzymatic extraction, structural characterization, and anticancer activity of polysaccharides from Rosa roxburghii Tratt fruit.

In this work, Rosa roxburghii Tratt fruit polysaccharides (RPs) were extracted by ultrasound-assisted enzymatic method. The highest extraction yield of RPs was 4.78 ±â€¯0.10 % under the optimal extraction conditions. Two purified fractions named RP1 and RP3 were obtained and systematically characterized by a combination strategy of FT-IR, monosaccharide composition, molecular weight distribution, methylation and 2D NMR spectroscopy analyses. Structural analysis showed that the main chain of RP1 was composed of rhamnogalacturonan type I (RG-I), while the side chains were rich in arabinogalactan and galactose. RP3 was composed of long homogalacturonan (HG) backbone interspersed with alternating sequences of RG-I domains, with galactose and arabinose side chains. RP1 and RP3 induced apoptosis of MCF-7 cells in a dose dependent manner in vitro especially for RP1, and had no effect on L929 cells. Furthermore, the possible anticancer mechanisms were revealed, and results suggested that RP1 induced apoptosis through ROS-dependent pathway and mitochondrial pathway. The results of this work not only provided an efficient extraction method and theoretical basis for the application of RPs, but also may contribute to develop novel functional foods or pharmaceutical products for the prevention and treatment of human breast cancer disease.

Ahf-Caltide, a Novel Polypeptide Derived from Calpastatin, Protects against Oxidative Stress Injury by Stabilizing the Expression of CaV1.2 Calcium Channel.

Reperfusion after ischemia would cause massive myocardial injury, which leads to oxidative stress (OS). Calcium homeostasis imbalance plays an essential role in myocardial OS injury. CaV1.2 calcium channel mediates calcium influx into cardiomyocytes, and its activity is modulated by a region of calpastatin (CAST) domain L, CSL54-64. In this study, the effect of Ahf-caltide, derived from CSL54-64, on myocardial OS injury was investigated. Ahf-caltide decreased the levels of LDH, MDA and ROS and increased heart rate, coronary flow, cell survival and SOD activity during OS. In addition, Ahf-caltide permeated into H9c2 cells and increased CaV1.2, CaVß2 and CAST levels by inhibiting protein degradation. At different Ca2+ concentrations (25 nM, 10 µM, 1 mM), the binding of CSL to the IQ motif in the C terminus of the CaV1.2 channel was increased in a H2O2 concentration-dependent manner. CSL54-64 was predicted to be responsible for the binding of CSL to CaV1.2. In conclusion, Ahf-caltide exerted a cardioprotective effect on myocardial OS injury by stabilizing CaV1.2 protein expression. Our study, for the first time, proposed that restoring calcium homeostasis by targeting the CaV1.2 calcium channel and its regulating factor CAST could be a novel treatment for myocardial OS injury.

Mesenchymal stem cell conditioned medium alleviates acute lung injury through KGF-mediated regulation of epithelial sodium channels.

Acute lung injury (ALI) is a progressive inflammatory injury, and mesenchymal stem cells (MSCs) can be used to treat ALI. MSC-conditioned medium (MSC-CM) contains many cytokines, in which keratinocyte growth factor (KGF) is a soluble factor that plays a role in lung development. We aim to explore the protective effects of MSCs secreted KGF on ALI, and investigate the involvement of epithelial sodium channel (ENaC), which are important in alveolar fluid reabsorption. Both lipopolysaccharides (LPS)-induced mouse and alveolar organoid ALI models were established to confirm the potential therapeutic effect of MSCs secreted KGF. Meanwhile, the expression and regulation of ENaC were determined in alveolar type II epithelial (ATII) cells. The results demonstrated that MSC-CM and KGF could alleviate the extent of inflammation-related pulmonary edema in ALI mice, which was abrogated by a KGF neutralizing antibody. In an alveolar organoid ALI model, KGF in MSC-CM could improve the proliferation and decrease the differentiation of ATII cells. At the cellular level, the LPS-inhibited protein expression of ENaC could be reversed by KGF in MSC-CM. In addition, bioinformatics analysis and our experimental data provided the evidence that the NF-κB signaling pathway may be involved in the regulation of ENaC. Our research confirmed that the therapeutic effect of MSC-CM on edematous ALI was closely related to KGF, which may be involved in the proliferation and differentiation of ATII cells, as well as the upregulation of ENaC expression by the inhibition of NF-κB signaling pathway.

The novel peptide athycaltide-1 attenuates Ang II-induced pathological myocardial hypertrophy by reducing ROS and inhibiting the activation of CaMKII and ERK1/2.

Pathological myocardial hypertrophy initially develops as an adaptive response to cardiac stress, which can be induced by many diseases. It is accompanied by adverse cardiovascular events, including heart failure, arrhythmias, and death. The purpose of this research was to explore the molecular mechanism of a novel peptide Athycaltide-1 (ATH-1) in the treatment of Ang II-induced pathological myocardial hypertrophy. In this study, the mRNA of Control group, Ang II group, ATH-1 group and Losartan group mice were sequenced by high-throughput sequencing technology. The results showed that the differentially expressed genes (DEGs) were significantly enriched in cell response to oxidative stress, regulation of reactive oxygen species metabolism and calmodulin binding. Then, the oxidation level of mouse hearts and H9c2 cardiomyocytes in each group and the expression of key proteins of CaMKII/HDAC/MEF2C and ERK1/2 signaling pathways were detected to preliminarily verify the positive effect of ATH-1. At the same time, the effect of ATH-1 was further determined by adding reactive oxygen species (ROS) inhibitor N-acetylcysteine (NAC) and CaMKII inhibitor AIP in vitro. The results showed that ATH-1 could significantly reduce the level of oxidative stress in hypertrophic cardiomyocytes and inhibiting the activation of CaMKII and ERK1/2.

Upconversion Nanoplatform Enables Multimodal Imaging and Combinatorial Immunotherapy for Synergistic Tumor Treatment and Monitoring.

Designing a novel nanoplatform that integrates multimodal imaging and synergistic therapy for precision tumor nanomedicines is challenging. Herein, we prepared rare-earth ion-doped upconversion hydroxyapatite (FYH) nanoparticles as nanocarriers coated and loaded respectively with polydopamine (PDA) and doxorubicin (DOX), i.e., FYH-PDA-DOX, for tumor theranostics. The developed FYH-PDA-DOX complexes exhibited desirable photothermal conversion, pH/near-infrared-irradiation-responsive DOX release, and multimodal upconversion luminescence/computed tomography/magnetic resonance imaging performance and helped monitor the metabolic distribution process of the complexes and provided feedback to the therapeutic effect. Upon 808 nm laser irradiation, the fast release of DOX facilitated the photothermal-chemotherapy effect, immunogenic cell death, and antitumor immune response. On combining with the anti-programmed cell death 1 ligand 1 antibody, an enhanced tri-mode photothermal-chemo-immunotherapy synergistic treatment against tumors can be realized. Thus, this treatment elicited potent antitumor immunity, producing appreciable T-cell cytotoxicity against tumors, amplifying tumor suppression, and extending the survival of mice. Therefore, the FYH-PDA-DOX complexes are promising as a smart nanoplatform for imaging-guided synergistic cancer treatment.

Exploration of interaction property between nonylphenol and G protein-coupled receptor 30 based on molecular simulation and biological experiments.

Nonylphenol (NP), a representative of environmental hormones, can cause extensive biological effects in the human body. In this study, we first analyzed the mutual binding modes of NP and G protein coupled estrogen receptor 30 (GPR30) by molecular simulation. The 3D structure of GPR30 was successfully constructed. We found that the binding sites of NP on GPR30 are similar to that of 17ß-Estradiol (E2) on GPR30. The GPR30-E2 bond complex is more stable than GPR30-NP bond complex. Next CCK-8 assay was used to detect the regulatory effect of NP on SKBR-3 cell proliferation. When NP and E2 were used alone, low concentration could promote cell proliferation, while high concentration was the opposite. The presence of E2 can promote the cell proliferation effect of NP, and inhibit the inhibitory intensity. NP could promote both the cell proliferation effect and inhibition intensity of E2. Based on our results, we conclude that the binding modes of NP and GPR30 is similar to that of E2 and GPR30. In biology, NP can play estrogen role by activating GPR30 receptor, but it can also produce cytotoxicity at higher concentration.

A poly(dimethylsiloxane)-based solid-phase microchip platform for dual detection of Pseudorabies virus gD and gE antibodies.

Pseudorabies caused by pseudorabies virus (PRV) infection is still a major disease affecting the pig industry; its eradication depends on effective vaccination and antibody (Ab) detection. For a more rapid and accurate PRV detection method that is suitable for clinical application, here, we established a poly(dimethylsiloxane)-based (efficient removal of non-specific binding) solid-phase protein chip platform (blocking ELISA) for dual detection of PRV gD and gE Abs. The purified gD and gE proteins expressed in baculovirus were coated into the highly hydrophobic nanomembrane by an automatic spotter, and the gray values measured by a scanner were used for the S/N (sample/negative) value calculation (gD and gE Abs standard, positive: S/N value ≤0.6; negative: S/N value >0.7; suspicious: 0.6 < S/N ≤ 0.7). The method showed an equal sensitivity in the gD Ab test of immunized pig serum samples compared to the neutralization test and higher sensitivity in the gE Ab test compared to the commercial gE Ab detection kit. In the clinical evaluation, we found an agreement of 100% (122/122) in the gD Ab detection compared to the neutralization test and an agreement of 97.5% (119/122) in the gE Ab detection compared to the commercial PRV gE Ab detection kit. In summary, the protein chip platform for dual detection of PRV gD and gE Abs showed high sensitivity and specificity, which is suitable for PRV immune efficacy evaluation and epidemic monitoring.

Self-Assembled Immunostimulatory Tetrahedral Framework Nucleic Acid Vehicles for Tumor Chemo-immunotherapy.

Some chemotherapeutic agents, such as anthracyclines and oxaliplatin, can induce immunogenic cell death (ICD) with additional immune responses against cancer. However, ICD-based immunotherapy is limited by the nonspecific distribution of drugs and various side effects. Here, an immunostimulatory self-assembled tetrahedral framework nucleic acid (tFNA) vehicle was constructed to potentiate the chemo-immunotherapy, in which doxorubicin (DOX) acted as a chemotherapeutic agent and an ICD-inducer. Meanwhile, the immunostimulatory CpG-tFNA was employed as a nanocarrier to deliver DOX and an adjuvant to enhance the immunotherapy. Damage-associated molecular patterns (DAMPs) generated by DOX from dying tumor cells, such as calreticulin (CRT), high mobility group protein 1(HMGB1), and adenosine triphosphate (ATP), can activate dendritic cells (DCs) and trigger an immunological response. Afterward, CpG-tFNA with immunostimulatory properties works to boost the DOX-induced immunotherapy. Consequently, CpG-tFNA/DOX showed excellent antitumor effects and immunological activation, including CD8+ T cell proliferation and antitumor cytokine TNF-α and IFN-γ secretion. Moreover, chemo-immunotherapy can also be enhanced synergistically when coadministered with PD-L1. In conclusion, CpG-tFNA/DOX promotes the ICD-associated chemo-immunotherapy and strengthens the connection between traditional chemotherapy and immunotherapy, representing a novel strategy for clinical application. Moreover, the concept of ICD-related immunotherapy can also be extended to other treatments such as radiotherapy which can induce immunogenic cell death as well.

Analysis of Therapeutic Targets of A Novel Peptide Athycaltide-1 in the Treatment of Isoproterenol-Induced Pathological Myocardial Hypertrophy.

Myocardial hypertrophy is a pathological feature of many heart diseases. This is a complex process involving all types of cells in the heart and interactions with circulating cells. This study is aimed at identifying the differentially expressed proteins (DEPs) in myocardial hypertrophy rats induced by isoprenaline (ISO) and treated with novel peptide Athycaltide-1 (ATH-1) and exploring the mechanism of its improvement. ITRAQ was performed to compare the three different heart states in control group, ISO group, and ATH-1 group. Pairwise comparison showed that there were 121 DEPs in ISO/control (96 upregulated and 25 downregulated), 47 DEPs in ATH-1/ISO (27 upregulated and 20 downregulated), and 116 DEPs in ATH-1/control (77 upregulated and 39 downregulated). Protein network analysis was then performed using the STRING software. Functional analysis revealed that Hspa1 protein, oxidative stress, and MAPK signaling pathway were significantly involved in the occurrence and development of myocardial hypertrophy, which was further validated by vivo model. It is proved that ATH-1 can reduce the expression of Hspa1 protein and the level of oxidative stress in hypertrophic myocardium and further inhibit the phosphorylation of p38 MAPK, JNK, and ERK1/2.

Activity of putative orexin neurons during cataplexy.

It is unclear why orexin-deficient animals, but not wild-type mice, show cataplexy. The current hypothesis predicts simultaneous excitation of cataplexy-inhibiting orexin neurons and cataplexy-inducing amygdala neurons. To test this hypothesis, we measured the activity of putative orexin neurons in orexin-knockout mice during cataplexy episodes using fiber photometry. We created two animal models of orexin-knockout mice with a GCaMP6 fluorescent indicator expressed in putative orexin neurons. We first prepared orexin-knockout mice crossed with transgenic mice carrying a tetracycline-controlled transactivator transgene under the control of the orexin promoter. TetO-GCaMP6 was then introduced into mice via an adeno-associated virus injection or natural crossing. The resulting two models showed restricted expression of GCaMP6 in the hypothalamus, where orexin neurons should be located, and showed excitation to an intruder stress that was similar to that observed in orexin-intact mice in our previous study. The activity of these putative orexin neurons increased immediately before the onset of cataplexy-like behavior but decreased (approximately - 20% of the baseline) during the cataplexy-like episode. We propose that the activity of orexin neurons during cataplexy is moderately inhibited by an unknown mechanism. The absence of cataplexy in wild-type mice may be explained by basal or residual activity-induced orexin release, and emotional stimulus-induced counter activation of orexin neurons may not be necessary. This study will serve as a basis for better treatment of cataplexy in narcolepsy patients.

YTHDF1 promotes breast cancer cell growth, DNA damage repair and chemoresistance.

Chemoresistance represents a major obstacle to the treatment of human cancers. Increased DNA repair capacity is one of the important mechanisms underlying chemoresistance. In silico analysis indicated that YTHDF1, an m6A binding protein, is a putative tumor promoter in breast cancer. Loss of function studies further showed that YTHDF1 promotes breast cancer cell growth in vitro and in vivo. YTHDF1 facilitates S-phase entry, DNA replication and DNA damage repair, and accordingly YTHDF1 knockdown sensitizes breast cancer cells to Adriamycin and Cisplatin as well as Olaparib, a PARP inhibitor. E2F8 is a target molecule by YTHDF1 which modulates E2F8 mRNA stability and DNA damage repair in a METTL14-dependent manner. These data demonstrate that YTHDF1 has a tumor-promoting role in breast cancer, and is a novel target to overcome chemoresistance.

The reduced contraction capacity of palatopharyngeal muscle in OSAHS is related to the decreased intra-cellular [Ca2+] mediated by low RyR1 and DHPRα1s expression.

PURPOSE: To aim of the study was to explore the possible mechanisms for the decreased contraction capacity of the palatopharyngeal muscle in cases with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Palatopharyngeal muscle specimens from patients with OSAHS were taken as the case group. Palatopharyngeal muscle tissue by surgical removal of oropharyngeal malignant tumors was used as a control cohort. The palatopharyngeal muscle contraction capacity was measured by assessing diaphragm peak-twitching force / cross-sectional area (Pt/CSA), fatigue index (FI) twitch tension, and force per cross-sectional area (Force/CSA). Myofibril and sarcoplasmic reticulum (SR) ultra-structures were observed by electron microscopy. The intra-cellular calcium concentration was measured by fluorescence spectrophotometry. DHPRα1s and RyR1 expression profiles were probed through RT-qPCR and Western blot, and the colocalization of them was determined by immunofluorescence. RESULTS: In comparison with the control cohort, the OSAHS cohort demonstrated decreased Pt/CSA (P < 0.01), FI twitch tension (P < 0.01), together with contraction capacity (P < 0.01). This cohort also had lower intra-cellular [Ca2+] of palatopharyngeal muscle cells with abnormal ultrastructure of sarcoplasmic reticulum (SR) (P < 0.01). In addition, transcriptomic (P < 0.01) and proteomic expression (P < 0.01) for RyR1 and DHPRα1s were markedly reduced within OSAHS cohort, although the degree of colocalization of them was not altered. CONCLUSION: RyR1 and DHPRα1s downregulation may disrupt intra-cellular [Ca2+] homeostasis and subsequently decrease the palatopharyngeal muscle contraction capacity in patients with OSAHS, thus providing a novel insight into the pathogenesis of OSAHS.

A novel theranostic nanoplatform for imaging-guided chemo-photothermal therapy in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is highly malignant and invasive, and current treatments are limited due to serious side effects and unsatisfactory outcomes. Here, we reported the terbium ion-doped hydroxyapatite (HATb) nanoparticle as a luminescent probe to encapsulate both the near-infrared (NIR) photothermal agent polydopamine (PDA) and anticancer doxorubicin (DOX) for imaging-guided chemo-photothermal therapy. The morphology, crystal structure, fluorescence, and composition of HATb-PDA-DOX were characterized. HATb-PDA showed a high DOX loading capacity. A theranostic nanoplatform showed pH/NIR responsive release properties and better antitumor outcomes in OSCC cells than monomodal chemotherapy or photothermal therapy, while keeping side effects at a minimum. Also, the luminescence signal was confirmed to be tracked and the increase of the red/green (R/G) ratio caused by the DOX release could be used to monitor the DOX release content. Furthermore, HATb-PDA-DOX plus NIR treatment synergistically promoted in vitro cell death through the overproduction of reactive oxygen species (ROS), cell cycle arrest, and increased cell apoptosis. Overall, this work presents an innovative strategy in designing a multifunctional nano-system for imaging-guided cancer treatment.

miR-27a acts as an oncogene to regulate endometrial cancer progression by targeting USP46.

Endometrial cancer (EC) ranks as the fourth most common diagnosed cancer type in females worldwide. MicroRNAs (miRNAs) are important regulators with crucial roles in regulating diverse biologic processes, including tumor initiation and progression. Previous studies have demonstrated that miR-27a was correlated with the tumorigenesis of various cancers. However, its expression and biologic role in EC remain to be determined. This study aimed to clarify whether miR-27a acts as an oncogene in endometrial cancer (EC) by downregulating ubiquitin specific peptidase 46 (USP46). Expression of miR-27a was measured by qRT-PCR, and the results demonstrated that miR-27a was upregulated in EC cell lines compared to normal cell lines. Cell counting kit-8 (CCK-8) and wound-healing assays demonstrated that overexpression of miR-27a significantly promoted cell proliferation and migration. Online prediction algorithm and dual luciferase activity reporter assay revealed that USP46 acts as a direct target of miR-27a. USP46 expression was downregulated in EC cell lines during miR-27a overexpression. Collectively, our results indicated that miR-27a targets USP46 to promote EC cell proliferation and migration, suggesting an oncogene role of miR-27a in EC.

Enhanced Penetrability of a Tetrahedral Framework Nucleic Acid by Modification with iRGD for DOX-Targeted Delivery to Triple-Negative Breast Cancer.

Poor penetrability and nonselective distribution of chemotherapeutic drugs are the main obstacles for chemotherapy for triple-negative breast cancer (TNBC). In our work, we developed a DNA-based drug delivery system to surmount these barriers. In addition, a tetrahedral framework nucleic acid (tFNA) was employed to load doxorubicin (DOX) with iRGD decoration to form a novel nanoparticle (tFNA/DOX@iRGD). The RGD sequence and the CendR motif in iRGD are used in tumor targeting and tissue penetration, respectively. Based on the sustained serum stability and pH-sensitive release behavior of DOX, tFNA/DOX@iRGD exhibited superiority for biomedical application. Moreover, tFNA/DOX@iRGD showed excellent deep penetration and drug accumulation in three-dimensional (3D) multicellular tumor spheroids compared to DOX and tFNA/DOX. Additionally, the therapeutic effect was verified in a 4T1 subcutaneous tumor model, and the complexes displayed a superior antitumor and antiangiogenic efficiency with fewer collateral damages. Therefore, these findings suggested that tFNA/DOX@iRGD might be a more effective pattern for drug delivery and TNBC therapy.

The LQT-associated calmodulin mutant E141G induces disturbed Ca2+-dependent binding and a flickering gating mode of the CaV1.2 channel.

Calmodulin (CaM) mutations are associated with congenital long QT (LQT) syndrome (LQTS), which may be related to the dysregulation of the cardiac-predominant Ca2+ channel isoform CaV1.2. Among various mutants, CaM-E141G was identified as a critical missense variant. However, the interaction of this CaM mutant with the CaV1.2 channel has not been determined. In this study, by utilizing a semiquantitative pull-down assay, we explored the interaction of CaM-E141G with CaM-binding peptide fragments of the CaV1.2 channel. Using the patch-clamp technique, we also investigated the electrophysiological effects of the mutant on CaV1.2 channel activity. We found that the maximum binding (Bmax) of CaM-E141G to the proximal COOH-terminal region, PreIQ-IQ, PreIQ, IQ, and NT (an NH2-terminal peptide) was decreased (by 17.71-59.26%) compared with that of wild-type CaM (CaM-WT). In particular, the Ca2+-dependent increase in Bmax became slower with the combination of CaM-E141G + PreIQ and IQ but faster in the case of NT. Functionally, CaM-WT and CaM-E141G at 500 nM Ca2+ decreased CaV1.2 channel activity to 24.88% and 55.99%, respectively, compared with 100 nM Ca2+, showing that the inhibitory effect was attenuated in CaM-E141G. The mean open time of the CaV1.2 channel was increased, and the number of blank traces with no channel opening was significantly decreased. Overall, CaM-E141G exhibits disrupted binding with the CaV1.2 channel and induces a flickering gating mode, which may result in the dysfunction of the CaV1.2 channel and, thus, the development of LQTS. The present study is the first to investigate the detailed binding properties and single-channel gating mode induced by the interaction of CaM-E141G with the CaV1.2 channel.