An Energy-Storing DNA-Based Nanocomplex for Laser-Free Photodynamic Therapy.

Photodynamic therapy (PDT) is a therapeutic strategy that is dependent on external light irradiation that faces a major challenge in cancer treatment due to the poor tissue-penetration depths of light irradiation. Herein, a DNA nanocomplex that integrates persistent-luminescence nanoparticles (PLNPs) is developed, which realizes tumor-site glutathione-activated PDT for breast cancer without exogenous laser excitation. The scaffold of the nanocomplex is AS1411-aptamer-encoded ultralong single-stranded DNA chain with two functions: i) providing sufficient intercalation sites for the photosensitizer, and ii) recognizing nucleolin that specifically overexpresses on the surface of cancer cells. The PLNPs in the nanocomplex are energy-charged to act as a self-illuminant and coated with a shell of MnO2 for blocking energy degradation. In response to the overexpressed glutathione in cancer cells, the MnO2 shell decomposes to provide Mn2+ to catalytically produce O2 , which is essential to PDT. Meanwhile, PLNPs are released and act as a self-illuminant to activate the photosensitizer to convert O2 into cytotoxic 1 O2 . Significant tumor inhibition effects are demonstrated in breast tumor xenograft models without exogenous laser excitation. It is envisioned that a laser-excitation-free PDT strategy enabled by the PLNP-DNA nanocomplex promotes the development of PDT and provides a new local therapeutic approach.

Circ_0004872 promotes platelet-derived growth factor-BB-induced proliferation, migration and dedifferentiation in HA-VSMCs via miR-513a-5p/TXNIP axis.

The proliferation, migration and dedifferentiation of vascular smooth muscle cells (VSMCs) exert crucial roles in atherosclerosis (AS) progression. The aim of our study was to explore the influences of circular RNA 0004872 (circ_0004872) in platelet-derived growth factor-BB (PDGF-BB)-induced AS cell model and investigate the underlying mechanisms. Real-time quantitative polymerase chain reaction (RT-qPCR) was implemented for the expression detection of circ_0004872, mitogen-activated protein kinase 1 (MAPK1) messenger RNA (mRNA), microRNA-513a-5p (miR-513a-5p) and thioredoxin interacting protein (TXNIP). Cell proliferation was analyzed via Cell Counting Kit 8 (CCK8) assay. Cell migration was assessed via wound healing assay and transwell migration assay. Western blot assay was used to measure the expression of alpha smooth muscle actin (α-SMA), osteopontin (OPN), calponin and TXNIP. Dual-luciferase reporter assay and RNA-pull down assay were used for confirmation of interaction between miR-513a-5p and circ_0004872 or TXNIP. Circ_0004872 expression was elevated in PDGF-BB-induced human aortic vascular smooth muscle cells (HA-VSMCs) and carotid plaque tissues. Circ_0004872 silencing alleviated PDGF-BB-induced proliferation, migration and dedifferentiation in HA-VSMCs. MiR-513a-5p bound to circ_0004872, and circ_0004872 knockdown-induced effects in PDGF-BB-treated HA-VSMCs were largely attenuated by the silencing of miR-513a-5p. MiR-513a-5p bound to the 3' untranslated region (3'UTR) of TXNIP, and miR-513a-5p overexpression-mediated effects were counteracted by the transfection of pcDNA-TXNIP in PDGF-BB-induced HA-VSMCs. TXNIP was modulated by circ_0004872/miR-513a-5p signaling cascade in HA-VSMCs. Circ_0004872 accelerated PDGF-BB-induced proliferation, migration and dedifferentiation in HA-VSMCs through enhancing TXNIP level via sponging miR-513a-5p.

Spatiotemporally programmable cascade hybridization of hairpin DNA in polymeric nanoframework for precise siRNA delivery.

DNA nanostructures have been demonstrated as promising carriers for gene delivery. In the carrier design, spatiotemporally programmable assembly of DNA under nanoconfinement is important but has proven highly challenging due to the complexity-scalability-error of DNA. Herein, a DNA nanotechnology-based strategy via the cascade hybridization chain reaction (HCR) of DNA hairpins in polymeric nanoframework has been developed to achieve spatiotemporally programmable assembly of DNA under nanoconfinement for precise siRNA delivery. The nanoframework is prepared via precipitation polymerization with Acrydite-DNA as cross-linker. The potential energy stored in the loops of DNA hairpins can overcome the steric effect in the nanoframework, which can help initiate cascade HCR of DNA hairpins and achieve efficient siRNA loading. The designer tethering sequence between DNA and RNA guarantees a triphosadenine triggered siRNA release specifically in cellular cytoplasm. Nanoframework provides stability and ease of functionalization, which helps address the complexity-scalability-error of DNA. It is exemplified that the phenylboronate installation on nanoframework enhanced cellular uptake and smoothed the lysosomal escape. Cellular results show that the siRNA loaded nanoframework down-regulated the levels of relevant mRNA and protein. In vivo experiments show significant therapeutic efficacy of using siPLK1 loaded nanoframework to suppress tumor growth.

Self-assembly of stem cell membrane-camouflaged nanocomplex for microRNA-mediated repair of myocardial infarction injury.

Mesenchymal stem cells-derived exosomes have shown promising therapeutic effect on myocardial infarction (MI). The major hurdles remain for the use of exosomes primarily due to the low yields from cell cultures coupled with complicated purification processes. Herein we report the self-assembly of stem cell membrane-camouflaged exosome-mimicking nanocomplex that recapitulates exosome functions, achieving efficient microRNA (miRNA) delivery and miRNA-mediated myocardial repair. The nanocomplex is constructed via the self-assembly of mesenchymal stem cell membrane on miRNA loaded mesoporous silica nanoparticle surface, which enables high miRNA loading capacity and protects miRNA from degradation in body fluid. The nanocomplex can escape the clearance of immunologic system, and target to ischemic injured cardiomyocytes. miRNA is triggered to release and binds to target mRNA, which inhibits the translation of apoptosis-related proteins, and consequently promotes the proliferation of cardiomyocytes. In the MI mouse model, the administration of exosome-mimicking nanocomplex effectively leads to preservation of viable myocardium and augmentation of cardiac functions.

Ablation of TMEM126B protects against heart injury via improving mitochondrial function in high fat diet (HFD)-induced mice.

The mitochondrial dysfunction in the pathogenesis of myocardial damage associated with high fat diet (HFD)-induced obesity remains largely unknown. Transmembrane protein 126B (TMEM126B), as a complex I assembly factor, plays a key role in regulating mitochondrial function. In the present study, the effects of TMEM126B on mitochondrial function were investigated using genetic knockout approach in HFD-induced mouse models with obesity. We found that TMEM126B was significantly increased in HFD-treated cardiac samples. Genetic ablation of TMEM126B alleviated HFD-mediated metabolic disorder and heart injury. TEM results suggested that cardiac mitochondrial integrity was improved in TMEM126B knockout mice compared with the wild type (WT) mice after HFD challenge. Additionally, the mitochondrial dysfunction induced by HFD was alleviated in mice with TMEM126B knockout, as evidenced by the decreased protein expression levels of dynamic-related protein-1 (DRP1) and fission-1 (FIS1) and increased expression of mitofusin-1 (MFN1). The mitochondrial impairments were further confirmed in palmitic acid (PA)-incubated cardiomyocytes, as evidenced by the down-regulated membrane potential and ATP levels, and by the up-regulated mitochondrial reactive oxygen species (ROS) production and DNA damage, which were significantly reversed by TMEM126B knockdown in vitro. Finally, TMEM126B ablation suppressed mitochondrial-dependent apoptotic death in the hearts of HFD mice. Therefore, TMEM126B led to mitochondrial impairments, contributing to the pathogenesis of HFD-induced cardiac injury, and blockage of TMEM126B could inhibit mitochondrial dysfunction, paving the road to new therapeutic modalities for the prevention of obesity-associated heart injury.

INPP4B promotes colorectal cancer cell proliferation by activating mTORC1 signaling and cap-dependent translation.

BACKGROUND AND OBJECTIVE: Inositol polyphosphate 4-phosphatase type II (INPP4B) is over-expressed in CRC tissues, and emerges as an oncogene. However, the mechanism by which INPP4B regulates CRC cell proliferation remains largely unclear. In this study, we aimed to investigate the regulatory mechanisms of INPP4B in CRC. MATERIALS AND METHODS: The expression levels of mRNA were detected by qRT-PCR. The expression levels of protein were determined by Western blot. Cell Counting Kit-8 (CCK-8) assays and BrdU incorporation assays were performed to evaluate cell proliferation abilities. Bicistronic luciferase assays and the m7GTP pull down assay were performed to measure the cap-dependent translation in cells. RESULTS: INPP4B promotes CRC cell proliferation by increasing mTORC1 activity. Furthermore, it was shown that the activation of mTORC1 signaling by INPP4B led to increased cap-dependent translation, which is essential for INPP4B-mediated CRC cell proliferation. Finally, it was demonstrated that increased AKT and serum and glucocorticoid-inducible kinase 1 activity contributed to the activation of cap-dependent translation induced by INPP4B. CONCLUSION: Collectively, the present study reveals INPP4B promotes colorectal cancer cell proliferation by activating mTORC1 signaling and cap-dependent translation.

A recyclable biointerface based on cross-linked branched DNA nanostructures for ultrasensitive nucleic acid detection.

The detection of specific nucleic acids is becoming increasingly important in the discovery of genetic diseases and clinical molecular diagnostics. Here we report a DNA nanostructure-based platform which enables a recyclable biointerface for ultra-sensitive detection of nucleic acid. We created a chemically cross-linked branched DNA nanostructure (CCLB-DNA) as the probe DNA to engineer the biointerfaces, thereby increasing probe distance, exposing more DNA probes from the interface into the solution phase, and thus enhancing the signal dramatically. In addition, DNA functionalized Fe3O4 nanoparticles were utilized for further signal amplification. The detection limit could go as low as 500 fM. Moreover, CCLB-DNA could endure denaturation conditions without disruption of duplex integrity; as a result, the recognition layer could be easily regenerated and the biointerface could be reused. Our CCLB-DNA represents an excellent prospect in the engineering of recyclable biointerface, which will be beneficial to many biosensing systems.

Integrated Biophysical and Biochemical Signals Augment Megakaryopoiesis and Thrombopoiesis in a Three-Dimensional Rotary Culture System.

Platelet transfusion has been widely used in patients undergoing chemotherapy or radiotherapy; however, the shortage of the platelet supply limits the care of patients. Although derivation of clinical-scale platelets in vitro could provide a new source for transfusion, the devices and procedures for deriving scalable platelets for clinical applications have not been established. In the present study, we found that a rotary cell culture system (RCCS) can potentiate megakaryopoiesis and significantly improve the efficiency of platelet generation. When used with chemical compounds and growth factors identified via small-scale screening, the RCCS improved platelet generation efficiency by as much as ∼3.7-fold compared with static conditions. Shear force, simulated microgravity, and better diffusion of nutrients and oxygen from the RCCS, altogether, might account for the improved efficient platelet generation. The cost-effective and highly controllable strategy and methodology represent an important step toward large-scale platelet production for future biomedical and clinical applications. Significance: Platelet transfusion has been widely used in patients undergoing chemotherapy or radiotherapy; however, the shortage of platelet supply limits the care of patients. Thus, derivation of clinical-scale platelets in vitro would provide a new source for transfusion. The present study evaluated a rotary suspension cell culture system that was able to potentiate megakaryopoiesis and significantly improved the efficiency of platelet generation. When used with chemical compounds and growth factors identified via small-scale screening, the three-dimensional system improved platelet generation efficiency compared with the static condition. The three-dimensional device and the strategy developed in the present study should markedly improve the generation of large-scale platelets for use in future biomedical and clinical settings.

Early and long-term results of combined cardiac surgery and neoplastic resection in patients with concomitant severe heart disease and neoplasms.

BACKGROUND: It is a surgical dilemma when patients present with both severe heart disease and neoplasms. The best surgical treatment remains controversial. This study aimed to analyze the early and long-term results of simultaneous surgical treatment of severe heart disease and neoplasms. METHODS: We reviewed the clinical records of 15 patients who underwent simultaneous neoplastic resection and cardiac surgery between September 2006 and January 2011. There were 5 male and 10 female patients. The mean age was (59.2 ± 12.5) years and the mean left ventricular ejection fraction was (57.4 ± 11.0)%. All patients were followed up completely for a period of 12 to 51 months (mean, (33.1 ± 11.2) months). RESULTS: Fifteen patients underwent simultaneous cardiac surgery and neoplastic resection. Cardiac procedures consisted of off pump coronary artery bypass grafting (n = 7), aortic valve replacement (n = 3), mitral valve replacement (n = 3), mitral valve replacement with coronary artery bypass grafting (n = 1) and left atrial myxoma resection (n = 1). Neoplastic resection consisted of lung cancer resection (n = 5), colonic cancer resection (n = 3), gallbladder resection (n = 1), colonic cancer resection with gallbladder resection (n = 1), hysterectomy (n = 2), hysterectomy with bilateral salpingo-oophorectomy (n = 2) and left ovariectomy (n = 1). Pathological examination confirmed malignant disease in 10 patients and benign disease in 5 patients. There were no perioperative myocardial infarctions, stroke, pericardial tamponade, renal failure or hospital deaths. The most frequent complications were atrial fibrillation (33.3%), pneumonia (26.7%), low cardiac output syndrome (6.7%) and delayed healing of surgical wounds (6.7%). There was 1 late death 42 months after surgery for recurrent malignant disease. At 1 and 3 years, survival rates were 100% (Kaplan-Meier method). CONCLUSIONS: Simultaneous cardiac surgery and neoplastic resection was not associated with increased early or late morbidity or mortality. Cardiopulmonary bypass does not appear to adversely affect survival in patients with malignant disease. The long-term survival was determined by tumor stage.

The human heart releases cardiotrophin-1 after coronary artery bypass grafting with cardiopulmonary bypass.

OBJECTIVES: Cardiotrophin-1 (CT-1) is closely linked to many cardiovascular diseases, such as myocardial infarction and heart failure, and exhibits cardioprotective effect in ischemia-reperfusion injury. The present study was designed to investigate the course of CT-1 in patients undergoing on-pump coronary artery bypass grafting (CABG), and to evaluate the relationship between plasma CT-1 levels and postoperative cardiac function. METHODS: Twenty-four patients undergoing elective CABG were studied. Radial artery blood samples were collected before cardiopulmonary bypass (CPB), 5 min and 20 min after reperfusion, and 1 h, 6 h, 12 h and 24 h after CPB. Coronary sinus blood samples were collected before CPB, 5 min and 20 min after reperfusion. Plasma CT-1 levels were measured using the ELISA method. Hemodynamic data were collected. RESULTS: Peripheral CT-1 levels did not change significantly postoperatively. Trans-myocardial CT-1 levels increased significantly 5 min and 20 minutes after reperfusion as compared to baseline. A weak positive correlation (r = 0.408, p = 0.048) was found between trans-myocardial CT-1 levels at 20 min after reperfusion and CI at 12 h after CPB. CONCLUSIONS: The heart secretes CT-1 after ischemic injury. The precise effect of CT-1 in CABG needs further investigation.