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Purpose:Epigenetic alterations play important roles in metastasis and drug resistance through gene regulation. However, the functional features and molecular mechanisms of epigenetic changes remain largely unclear in nasopharyngeal carcinoma (NPC) metastasis.Experimental Design:Gene regulatory network analysis was used to identify metastatic-specific dysregulated genes between normal and NPC tissues and the expression was validated in published Gene-Expression Omnibus data set. The regulatory and functional role of RAB37 downregulation was examined in NPC and was validated in vitro and in vivo, and downstream target of RAB37 was explored. The clinical value of RAB37 methylation was evaluated in NPC metastasis and chemosensitivity.Results:We identified RAB37 as a specific hypermethylated gene that is most commonly downregulated in NPC. Moreover, RAB37 downregulation was attributed to hypermethylation of its promoter and was significantly associated with metastasis- and docetaxel chemoresistance-related features in NPC. Ectopic RAB37 overexpression suppressed NPC cell metastasis and enhanced chemosensitivity to docetaxel. Mechanistically, RAB37 colocalized with TIMP2, regulated TIMP2 secretion, inhibited downstream MMP2 activity, and consequently altered NPC cell metastasis. Furthermore, RAB37 hypermethylation was correlated with poor clinical outcomes in patients with NPC. We developed a prognostic model based on RAB37 methylation and N stage that effectively predicted an increased risk of distant metastasis and a favorable response to docetaxel-containing induction chemotherapy (IC) in NPC patients.Conclusions:This study shows that RAB37 hypermethylation is involved in NPC metastasis and chemoresistance, and that our prognostic model can identify patients who are at a high risk of distant metastasis and might benefit from for docetaxel IC.

Supplementary Data from RAB37 Hypermethylation Regulates Metastasis and Resistance to Docetaxel-Based Induction Chemotherapy in Nasopharyngeal Carcinoma

Epitranscriptomic remodeling such as N

Background: Glioma is the most common tumor of the central nervous system, which has a high mortality and recurrence rate. Increasing evidence shows that long noncoding RNAs (lncRNA) are closely re...

Purpose: Cisplatin-based chemotherapy effectively improves the distant-metastasis control in nasopharyngeal carcinoma (NPC), but approximately 30% of patients develop treatment failure due to chemoresistance. However, the underlying mechanisms remain poorly understood. Experimental Design: Circular RNA (circRNA) sequencing data were used to identify metastasis-specific circRNAs and the expression of circIPO7 was validated in NPC tissues as well as NPC cell lines by qRT-PCR. The whole transcriptional profile upon circIPO7 knockdown was applied to explore the biological function and regulatory mechanism, which were further confirmed by in vitro and in vivo metastasis/chemosensitivity assays. We also evaluated the value of circIPO7 expression in predicting NPC metastasis and cisplatin chemoresistance by analyzing a cohort of 183 NPC patients. Results: In this study, circIPO7, a novel circRNA, is found to be specifically overexpressed in NPC patients with distant metastasis. Knockdown of circIPO7 in NPC cells suppresses their metastasis and increases sensitivity to cisplatin treatment in vitro and in vivo. Mechanistically, circIPO7 binds to Y-box binding protein-1 (YBX1) protein in the cytoplasm and facilitates its phosphorylation at serine 102 (p-YBX1S102) by the kinase AKT, which further promotes YBX1 nuclear translocation and activates FGFR1, TNC, and NTRK1 transcription. Clinically, higher circIPO7 expression indicates unfavorable distant metastasis-free survival in NPC patients given cisplatin-based chemotherapy. Conclusions: Altogether, this study identifies oncogenic circIPO7 as a prognostic marker after cisplatin-based chemotherapy and as a potential therapeutic target for overcoming metastasis and chemoresistance in NPC.

Choroidal neovascularization (CNV) is the key pathological change caused by irreversible blindness resulting from neovascular AMD (nAMD). However, the pathological mechanisms underlying CNV remain largely unknown. Here, we aimed to investigate the role of miR-146a-5p in CNV formation.At the cellular level, we overexpressed or downregulated miR-146a-5p in an umbilical vein endothelial cell line (EA.hy926) by transfecting cells with either a miR-146a-5p mimic or an inhibitor. CCK8, wound healing, and Matrigel assays were performed to examine the proliferation, migration, and tube formation of endothelial cells (EA.hy926). Target relationship between miR-146a-5p and OTUD7B was verified using a double luciferase reporter experiment. An experimental CNV model was established by treating fundi of male C57BL/6 J mice with 810 nm laser. Fundus fluorescein angiography (FFA) was performed to evaluate the leakage of CNV on day 7 after miR-146a-5p antagomir intravitreal injection. The CNV volume was measured using Choroidal Flatmounts in a confocal study. The expression levels of VEGF, ICAM1, and NF-κB (p50 and p65) were detected both in vitro and in vivo.The expression of miR-146a-5p was increased in LPS-stimulated endothelial cells and in experimental CNV RPE-choroidal complexes in mouse models. LPS-induced proliferation, migration, and tube formation were inhibited by the miR-146a-5p inhibitor. The miR-146a-5p antagomir attenuated CNV formation and fluorescent leakage in the vivo CNV model. In the LPS-stimulated endothelial cells and the CNV mouse model, the NF-κB signaling pathway was activated and the expression of VEGF and ICAM1 increased. Conversely, downregulation of miR-146a-5p inactivated the NF-κB signaling pathway and reduced the expression of VEGF and ICAM1.Our results indicated that downregulation of miR-146a-5p inhibited experimental CNV formation via inactivation of the NF-κB signaling pathway.

Super-resolution (SR) in medical imaging is an emerging application in medical imaging due to the needs of high quality images acquired with limited radiation dose, such as low dose Computer Tomography (CT), low field magnetic resonance imaging (MRI). However, because of its complexity and higher visual requirements of medical images, SR is still a challenging task in medical imaging. In this study, we developed a deep learning based method called Medical Images SR using Generative Adversarial Networks (MedSRGAN) for SR in medical imaging. A novel convolutional neural network, Residual Whole Map Attention Network (RWMAN) was developed as the generator network for our MedSRGAN in extracting the useful information through different channels, as well as paying more attention on meaningful regions. In addition, a weighted sum of content loss, adversarial loss, and adversarial feature loss were fused to form a multi-task loss function during the MedSRGAN training. 242 thoracic CT scans and 110 brain MRI scans were collected for training and evaluation of MedSRGAN. The results showed that MedSRGAN not only preserves more texture details but also generates more realistic patterns on reconstructed SR images. A mean opinion score (MOS) test on CT slices scored by five experienced radiologists demonstrates the efficiency of our methods.

Accurate risk stratification for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) is crucial for treatment decisions and prognosis. Here, we introduce a circRNA-based classifier that could improve the prognostic stratification of LA-NPC patients. The circRNAs are identified by microarray profiling, followed by qRT-PCR validation and selection using a machine learning method in the training cohort (n = 170). Based on the proposed classifier, two prognostic-distinctive NPC subtypes are identified, namely the high-risk subtype (subtype H) and low-risk subtype (subtype L), which have significantly different disease-free survival (HR 2.99, 95% CI 1.58-5.67, P < 0.001). Validation in the internal cohort (n = 170) and external cohort (n = 150) yield similar results and the circRNA-based classifier is an independent risk factor of posttreatment relapse. Meanwhile, multiple interdependent features of different subtypes are observed, including relatively higher immune cell infiltration and immune-related pathways activation in subtype L; and predominant stromal, immunosuppressive and tumor-promoting components with moderate immune activation in subtype H. With a less aggressive and more immune-active tumor microenvironment, patients of subtype L could benefit from the addition of induction chemotherapy. In contrast, patients of subtype H, who are vulnerable to chemoresistance, display a strong tendency to benefit from additional immunotherapy. Overall, we define two NPC prognostic subtypes based on a circRNA classifier across multiple cohorts, which exhibit distinct biological ecosystems and suggest opportunities for the personalization of therapeutic regimens. Citation Format: Yelin Liang, Yuheng Zhao, Qian Li, Wei Jiang, Jun Ma, Na Liu, Yingqin Li. Identification and characterization of nasopharyngeal carcinoma prognostic subtypes based on a circRNA classifier: Implications of stratified treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5128.

Inflammation and tissue infiltration by various immune cells play a significant role in the pathogenesis of neurons suffering the central nervous systems diseases. Although brachial plexus root avulsion (BPRA) leads to dramatic motoneurons (MNs) death and permanent loss of function, however, the knowledge gap on cytokines and glial reaction in the spinal cord injury is still existing. The current study is sought to investigate the alteration of specific cytokine expression patterns of the BPRA injured spinal cord during an acute and subacute period. The cytokine assay, transmission electron microscopy, and histological staining were utilized to assess cytokine network alteration, ultrastructure morphology, and glial activation and MNs loss within two weeks post-injury on a mouse unilateral BPRA model. The BPRA injury caused a progressively spinal MNs loss, reduced the alpha-(α) MNs synaptic inputs, whereas enhanced glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor molecule-1 (IBA-1), F4/80 expression in ipsilateral but not the contralateral spinal segments. Additionally, cytokine assays revealed BPRA significantly altered the level of CXCL1, ICAM1, IP10, MCP-5, MIP1-α, and CD93. Notably, the elevated MIP1-α was mainly expressed in the injured spinal MNs. While the re-distribution of CD93 expression, from the cytoplasm to the nucleus, occasionally occurred at neurons of the ipsilateral spinal segment after injury. Overall, these findings suggest that the inflammatory cytokines associated with glial cell activation might contribute to the pathophysiology of the MNs death caused by nerve roots injury.

Purpose: To investigate whether triptolide-nanoliposome-APRPG (TP-nanolip-APRPG), a novel sustained-release nano-drug delivery system that targets vascular endothelial cells, could enhance the inhibition of triptolide (TP) on laser-induced choroidal neovascularization (CNV). Methods: TP was encapsulated with or without APRPG (Ala-Pro-Arg-Pro-Gly) peptide-modified nanoliposomes. CNV was induced by laser photocoagulation in C57BL/6J mice. One microliter of 10 μg free TP monomer, TP-nanolip containing 10 μg TP, TP-nanolip-APRPG containing 10 μg TP, or an identical volume of PBS was intravitreally injected in mice immediately after laser photocoagulation. Seven days after laser photocoagulation, CNV volumes were calculated in each group. Infiltration of M2 macrophages as well as protein levels of vascular endothelial growth factor (VEGF) and inflammatory factors including ICAM-1 and MCP-1 in the RPE-choroid complex were determined. In vitro assays for cell proliferation, migration, and tube formation were also performed. Results: TP-nanolip-APRPG was successfully synthesized and exhibited good TP delivery and enhanced the cellular uptake of TP in vitro. In vitro studies showed that TP-nanolip-APRPG was a better inhibitor of cell proliferation (31.34 ± 3.89 % vs 41.25 ± 4.67 % vs 53.55 ± 5.76 %), migration (62.60 ± 8.88 vs 104.60 ± 13.32 vs 147.00 ± 13.15), and tube formation (681.26 ± 108.15 vs 926.75 ± 54.01 vs 1189.84 ± 157.14) than TP-nanolip or free TP (all P 0.05, n=6). Conclusions: TP-nanolip-APRPG, a novel sustained-release drug delivery system targeting endothelial cells of CNV lesions, could enhance TP inhibition of the development of CNV without toxicity in the retina, suggesting therapeutic potential for CNV-related diseases in future clinical practice.

Objectives To retrospectively analyze the CT imaging features and patterns at baseline and as they evolve with time as the disease progresses or resolves in a cohort of pediatric patients affected with 2019 corona virus disease (COVID-19) pneumonia from three different cities in China.Methods We evaluated 29 pediatric patients with COVID-19 in the authors’ institution from Jan 1 to Feb 20, 2020. Cases were confirmed by laboratory test and were analyzed for epidemiological, demographic, clinical, radiological features and patterns.Results 29 initial scans and 23 follow-up scans were obtained from 29 patients. 15(52%) patients had been to Hubei Province and 26 (90%) of them had close contact with the COVID-19 positive patients in 14 days prior to the illness onset. The peak severity time was 5-8 days after symptom onset. A significant difference between the number of involved segments at different time points was indicated (p=0.019). Half (52%) of the laboratory confirmed patients had no CT positive findings. Nine (31%) of the laboratory confirmed patients had no symptoms. Six (21%) had no CT positive findings nor symptoms. All the patients of one center(n=6) whose fecal samples remained positive after the respiratory samples became negative.Conclusion The common positive CT findings included ground-glass opacities (50%), ground-glass opacities mixed with consolidation (36%), peribronchial thickening (21%), and consolidations (14%). We recommend for pediatric patients CT should not be used as a first-line test to diagnose COVID-19.

Objectives To retrospectively analyze the most common imaging features on CT at baseline and as they evolve with time as the disease progresses or resolves in a cohort of patients affected with 2019 coronal virus disease (COVID-19) pneumonia in Zhuhai, China.Methods We evaluated 38 patients with COVID-19 in the authors’ institution from Jan 1 to Jan 31, 2020. Cases were confirmed by real-time RT-PCR and were analyzed for epidemiological, demographic, clinical, and radiological features. Outcomes were followed up until Feb 18, 2020. Results 38 initial scans and 62 follow-up scans were obtained. 28 (74%) patients had the history of travel to or residence in Hubei Province of China in 14 days prior to the illness onset. Common findings included ground-glass opacification (GGO), sometimes mixed with consolidation, and interlobular septal and intralobular interstitial thickening. Follow-up imaging often demonstrated peripheral GGO and consolidations spreading to the remainder of the lungs and the increasing consolidative component reflecting the progression of the disease. 8 patients (21%) whose swabs or serum were positive for COVID-19 had no imaging findings on CT throughout the disease course. After treatment the serum and sputum tests became negative for COVID-19 in 32(84%) cases. 28(74%) patients were discharged and three (8%) of them were transferred to the Observation Ward, while seven (18%) patients were kept in Isolation Ward. Conclusion The commonest pattern observed was GGO alone or GGO mixed with consolidation predominantly in lower and peripheral lungs. The follow-up CT scan is crucial for the diagnosis and evaluation of the disease process.

Additional file 1: Figure S1. Schematic map of circRNA isoforms arising from CRIM1 genome and relative circCRIM1 expression in NPC cells and tissues. Figure S2. Knockdown and overexpression efficiency of circCRIM1 or miR-422a in NPC cells. Figure S3–4. Multiple sequence alignment of two independent siRNAs targeting circCRIM1 and 15 circRNA isoforms derived from CRIM1 gene in S18 cells. Figure S5. Transwell assays for the rescue effects of circCRIM1 with a mutant backsplice junction of circCRIM1. Figure S6. CircCRIM1 induces EMT in NPC cells. Figure S7. FOXQ1 is a downstream target of miR-422a and circCRIM1 involved in metastasis. Figure S8. FOXQ1 downregulation inhibited NPC cell metastasis in vivo. Figure S9. circCRIM1 downregulation enhances the docetaxel efficacy on NPC cell metastasis in vivo. Figure S10. Patients in the combined intermediate and high risk groups did not benefit from docetaxel-containing induction chemotherapy. Figure S11. Full unedited Western blotting gels for all figures. Table S1: List of 15 circRNA isoforms derived from CRIM1 gene in S18 cells. Table S2. Downregulated miRNAs according to miRNA microarray. Table S3. Putative miRNAs predicted to bind circCRIM1 by miRanda and RNAhybrid algorithms. Table S4. Putative miRNAs predicted to bind circCRIM1 by StarBase algorithms. Table S5. Clinical characteristics of NPC patients according to high and low circCRIM1 expression. Table S6. Univariate and multivariable Cox regression analysis of circCRIM1 expression level and survival in NPC patients. Table S7. Primers and RNA sequences used in this study.

Citrus fruits are a rich source of vitamin C and phytochemicals and can be an important part of a healthy diet. Citrus is believed to prevent the occurrence or shorten the duration of symptoms of the common cold and influenza, but meta-analysis of vitamin C clinical trial data is inconclusive. We examined whether citrus flavonoids activated antiviral pathways that might explain the perceived efficacy against the common cold and influenza. We found that a citrus bioflavonoid blend augmented NFkB activation in the presence of imiquimod. In addition, the citrus bioflavonoid blend, as well as individual flavonoids found in the blend, activated the interferon-stimulated response element (ISRE). The ability to activate the ISRE appeared to due to the flavonoids’ ability to upregulate expression of the transcription factor interferon regulatory factor 7 (IRF7). Our results suggest that flavonoids from citrus may stimulate antiviral pathways due to their ability to activate the ISRE.

Background Choroidal neovascularization (CNV) is a common cause of irreversible blindness in elderly patients in developed countries, and subretinal fibrosis is an advanced stage of CNV. Currently, there is no effective clinical treatment for subretinal fibrosis. Purpose To investigate whether intravitreal injection of triptolide (TP) could attenuate subretinal fibrosis and determine its underlying mechanisms. Methods CNV was induced by laser photocoagulation in C57BL/6J mice. Immediately after laser photocoagulation, 1 μl of free TP (10 μg), TP-nanolip-PEG (TP-loaded PEGylated nanoliposomes containing 10 μg TP), or the same volume of phosphate-buffered saline (PBS) was intravitreally administered to each respective group. Areas and ratios of subretinal fibrosis were calculated seven days after laser injury. Additionally, expression levels of M2 macrophage-related markers, molecules of the transforming growth factor (TGF)-β1/Smad signaling pathway, and markers for epithelial-mesenchymal transition (EMT) and endothelial-to-mesenchymal transition (EndoMT) were detected both in vitro and in vivo. Results The areas of subretinal fibrosis were significantly reduced in both the free TP (10993.87 ± 2416.90 μm2) and TP-nanolip-PEG (7695.32 ± 2121.91 μm2) groups when compared with the PBS group (15971.97 ± 3203.10 μm2) (p Conclusions TP could attenuate subretinal fibrosis by suppressing the polarization of M2 macrophages and TGF-β1 induced EMT/EndoMT. TP-nanolip-PEG enhanced the inhibitory effects of TP on subretinal fibrosis, suggesting its therapeutic potential for CNV-related subretinal fibrosis.

Stimuli-responsive gene delivery vectors based on physiologically triggered structure changing have been recently recognized as a new therapeutic agent for their excellent performance in vivo. Herein, we present an intelligent gene delivery system based on the octa-arginine peptides (R8)-conjugated polyamino acid derivatives noted as PPCRC (PVIm-(PAsp-Cystamine-R8)-Cholesteryl), which processed pH responsive, surface charge-switching, intracellular redox-responsive and enhanced nucleus import of gene together. Due to the imidazole group in the PPCRC backbone, the DNA/PPCRC polyplexes not only exhibited the enhanced buffering capacity in the endosome after endocytosis, but also displayed the reversible surface charge from negative to positive with decreasing the pH value form pH 7.4 to pH 6.5–6.8, which would promote the cell membrane binding and cellular uptake. The disulfide bond for R8 peptides conjugation in the polymer side chain could be rapidly cleaved under reductive conditions, facilitating DNA release in the cytoplasm. Subsequently, the DNA would be still associated with the R8 peptides, which would promote the intracellular nucleus import of DNA. The luciferase gene expression level of COS-7 cells transfected by DNA/PPCRC polyplexes was almost 2000 folds higher than cells transfected by DNA/PPCC polyplexes (without R8 peptides modification) in growth-arrested cell model. Nearly 10 folds enhanced gene transfection efficiency was found on human bone mesenchymal stem cells (hBMSCs) using the same strategy, which revealed that this intelligent vector can be also utilized in transfection of non-dividing cells. Intravenous injection of the DNA/PPCRC polyplexes also achieved the effective transfection in subcutaneous tumor model. Taken together, PPCRC vector has great potential for both dividing and non-dividing cells transfection and in vivo gene delivery application.

For successful gene therapy, it is imperative to accumulate therapeutic gene in tumor tissues followed by efficiently delivering gene into targeted cells. Ultrasound irradiation, as a noninvasive and cost-effective external stimulus, has been proved to be one of the most potential external-stimulating gene delivery strategies recently in further improving gene transfection. In this study, we developed tumor-targeting ultrasound-triggered phase-transition nanodroplets AHNP-PFP-TNDs comprising a perfluorinated poly(amino acid) C11F17–PAsp (DET) as a core for simultaneously loading perfluoropentane (PFP) and nucleic acids, and a polyanionic polymer PGA-g-PEG-AHNP as the shell for not only modifying the surface of nanodroplets but also introducing an anti-Her2/neu peptide (AHNP) aiming to targeted treatment of Her2-overexpressing breast cancer. The results showed the average diameter of AHNP-PFP-TNDs was below 400 nm, nearly spherical in shape. The modification of PGA-g-PEG-AHNP not only increased the serum s...

The neuronal mechanisms underlying brachial plexus roots avulsion-induced motoneuron death are unknown. Our previous studies showed that the avulsion induced obvious temporal and spatial expression of both degenerative and regenerative genes in the injured spinal cord tissue. Therefore, we hypothesized that lncRNAs (responsible for epigenetic molecular mechanisms) are altered (resulting in altered gene expression patterns) at days 3 and 14 after avulsion. In the present microarray study, 121 lncRNAs (83 up/38 down) and 844 mRNAs (726 up/118 down) were differentially expressed (ipsilateral vs contralateral) after avulsion. We further used qRT-PCR as a validation tool to confirm the expression patterns of 5 lncRNAs and 5 mRNAs randomly selected from our microarray analysis data. The gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to identify the critical biological processes and pathways. The noted downregulation of the AF128540 (which targets the nNOS gene) is consistent with the high expression of nNOS protein observed at day 14 post-avulsion. The downregulation of MRAK034299, whose target is the Adra1d gene, is consistent with the downregulation of Adra1d mRNA and protein at days 3 and 14 post avulsion. Immunofluorescence evaluation showed cytoplasmic translocation of ECEL1 after avulsion injury. Moreover, we also found that IL6 and Rac2 are the core genes at days 3 and 14 after unilateral brachial plexus roots avulsion, respectively. Overall, our present data suggest that the altered LncRNAs (avulsion-induced), via unknown epigenetic mechanisms, certainly contribute to the molecular mechanism underpinning motoneuron death or survival. Therefore, the avulsion-induced differentially expressed lncRNAs and mRNAs may offer potential diagnostic and therapeutic targets for BPRA.

Gastric cancer (GC), particularly of the type with high expression of both human epidermal growth factor receptor 2 (Her2) and cluster determinant 44 (CD44), is one of the most malignant human tumors which causes a high mortality rate due to rapid tumor growth and metastasis. To develop effective therapeutic treatments, a dual-targeting hybrid nanoparticle (NP) system was designed and constructed to deliver the SN38 agent specifically to human solid gastric tumors bearing excessive Her2 and CD44. The hybrid NPs consist of a particle core made of the biodegradable polymer PLGA and a lipoid shell prepared by conjugating the AHNP peptides and n-hexadecylamine (HDA) to the carboxyl groups of hyaluronic acid (HA). Upon encapsulation of the SN38 agent in the NPs, the AHNP peptides and HA on the NP surface allow preferential delivery of the drug to gastric cancer cells (e.g., HGC27 cells) by targeting Her2 and CD44. Cellular uptake and in vivo biodistribution experiments verified the active targeting and prolonged in vivo circulation properties of the dual-targeting hybrid NPs, leading to enhanced accumulation of the drug in tumors. Furthermore, the anti-proliferation mechanism studies revealed that the inhibition of the growth and invasive activity of HGC27 cells was not only attributed to the enhanced cellular uptake of dual-targeting NPs, but also benefited from the suppression of CD44 and Her2 expression by HA and AHNP moieties. Finally, intravenous administration of the SN38-loaded dual-targeting hybrid NPs induced significant growth inhibition of HGC27 tumor xenografted in nude mice compared with a clinical antitumor agent, Irinotecan (CPT-11), and the other NP formulations. These results demonstrate that the designed dual-targeting hybrid NPs are promising for targeted anti-cancer drug delivery to treat human gastric tumors over-expressing Her2 and CD44.

We have developed new, efficient gene delivery systems based on PEGylated poly(lactone-co-β-amino ester) block copolymers that are biodegradable, stable and low in toxicity. The PEG-poly[PDL-co-3-(4-(methylene)piperidin-1-yl)propanoate] (PEG-PPM) diblock and PPM-PEG-PPM triblock copolymers with various compositions were synthesized in one step via lipase-catalyzed copolymerization of ω-pentadecalactone (PDL) and ethyl 3-(4-(hydroxymethyl)piperidin-1-yl)propanoate (EHMPP) with an appropriate PEG (MeO-PEG-OH or HO-PEG-OH). The amphiphilic block copolymers are capable of condensing DNA in aqueous medium via a self-assembly process to form polyplex micelle nanoparticles with desirable particle sizes (70-140 nm). These micelles possess low CMC values and are stable in the medium containing serum protein molecules (FBS). Among the PEG-PPM and PPM-PEG-PPM micelles, the PEG-PPM-15% PDL micelle particles exhibited high DNA-binding ability, the fastest cellular uptake rate and highest gene transfection efficacy. Flow cytometry analysis shows that LucDNA/PEG-PPM-15% PDL polyplex micelles can effectively escape from endosomal degradation after cellular uptake likely due to the presence of the tertiary amine groups in the copolymer chains that act as proton sponges. In vitro cytotoxicity and hemolysis assay experiments indicate that all copolymer samples are nonhemolytic and have minimal toxicity toward COS-7 cells within the polymer concentration range (≤200 μg/mL) used for the gene transfection. These results demonstrate that the PEGylated poly(lactone-co-β-amino ester) block copolymers are promising new vectors for gene delivery applications.

Ultrasound as an external stimulus for enhanced gene transfection represents a safe, noninvasive, cost-effective delivery strategy for gene therapy. Herein, we have developed an ultrasound-triggered phase-transition cationic nanodroplet based on a novel perfluorinated amphiphilic poly(amino acid), which could simultaneously load perfluoropentane (PFP) and nucleic acids. The heptadecafluoroundecylamine (C11F17-NH2) was chosen to initiate β-benzyl-L-aspartate N-carboxyanhydride (BLA-NCA) ring-opening polymerization to prepare C11F17-poly(β-benzyl-L-aspartate) (C11F17-PBLA). Subsequently, C11F17-poly{N-[N'-(2-aminoethyl)]aspartamide} [C11F17-PAsp(DET)] was synthesized by aminolysis reaction of C11F17-PBLA with diethylenetriamine (DET). PFP/pDNA-loaded nanodroplets PFP-TNDs [PFP/C11F17-PAsp(DET)/LucDNA/γ-PGA or poly(glutamic acid)-g-MeO-poly(ethylene glycol) (PGA-g-mPEG) ternary nanodroplets] were primarily formulated by an oil/water emulsification method, followed by surface modification with PGA-g-mPEG. The average diameter of PFP-TNDs ranged from 300 to 400 nm, and transmission electron microscopy images showed that the nanodroplets were nearly spherical in shape. The ζ potential of the nanodroplets dramatically decreased from +54.3 to +15.3 mV after modification with PGA-g-mPEG, resulting in a significant increase of the stability of the nanodroplets in the serum-containing condition. With ultrasound irradiation, the gene transfection efficiency was enhanced 14-fold on HepG2 cells, and ultrasound-triggered phase-transition cationic nanodroplets also displayed a good ultrasound contrast effect. These results suggest that the PFP/DNA-loaded phase-transition cationic nanodroplets can be utilized as efficient theranostic agents for targeting gene delivery.

We have designed and constructed novel multifunctional nanoparticle drug-delivery systems that are stable under physiological conditions and responsive to tumor-relevant pH and intracellular reduction potential. The nanoparticles were fabricated from enzymatically synthesized poly(ethylene glycol) (PEG)-poly(ω-pentadecalactone-co-N-methyldiethyleneamine-co-3,3'-dithiodipropionate) (PEG-PPMD) and PEG-poly(ε-caprolactone-co-N-methyldiethyleneamine-co-3,3'-dithiodipropionate) (PEG-PCMD) block copolymers via self-assembly processes in aqueous solution. At acidic pH and in the presence of a reductant (e.g., d,l-dithiothreitol or glutathione), the nanosized micelle particles rapidly swell and disintegrate due to the protonation of amino groups and reductive cleavage of disulfide bonds in the micelle cores. Consistently, docetaxel (DTX)-loaded PEG-PPMD and PEG-PCMD micelles can be triggered synergistically by acidic endosomal pH and a high intracellular reduction potential to rapidly release the drug for efficient killing of cancer cells. The drug formulations based on PEG-PPMD and PEG-PCMD copolymers exhibited a substantially higher potency than free DTX in inhibiting tumor growth in mice, whereas their therapeutic effects on important organ tissues were minimal. These results demonstrate that PEG-PPMD and PEG-PCMD nanoparticles have a great potential to serve as site-specific, controlled drug-delivery vehicles for safe and efficient antitumor treatment.

Gene therapy provides an alternative and effective method for treatment of genetic diseases and cancers that are refractory to conventional therapeutics. The success of gene therapy is largely dependent on the development of safe and effective gene delivery vectors for transporting genetic material from the blood stream to the cytoplasm or nucleus. Current gene vectors can be divided into viral and non-viral vectors. Although non-viral gene delivery carriers can offer some advantages, such as safety and facile fabrication, they do not possess the same high gene transfection efficiency as viral vectors due to a lack of functionality to overcome extra- and intracellular gene delivery obstacles. On the basis of these disadvantages, researchers are developing "smart" non-viral gene-delivery carriers in order to overcome the physiological barriers and realize efficient gene transfection. These "smart" stimuli-responsive carriers can undergo physical or chemical reactions in response to internal tumor-specific environments, such as pH conditions, redox potentials, enzymatic activations and thermal gradients, as well as external stimulations, such as ultrasound, light, magnetic fields, and electrical fields. Furthermore, "smart" carriers can also be triggered by dual or multiple combinations of different stimuli. In this review, we highlight the recent stimuli-sensitive polymeric nanocarriers for gene delivery, and we discuss the potential of combining multiple stimuli-responsive strategies for future gene therapy applications.

Highlights • Multiple tumor-like ectopic calcifications is a rare syndrome. • Complete excisions of the ectopic calcifications were performed, without signs of recurrence in the same sites at follow-up. • Incomplete excision of the ectopic calcification in the right shoulder resulted in recurrence in the same site. • Subtotal parathyroidectomy with parathyroid autotransplantation appeared not to inhibit the recurrence of ectopic calcification in patients with CRF., Background Multiple tumor-like ectopic calcifications is a rare syndrome characterized by subcutaneous mass deposits of calcium phosphate in periarticular tissues. Although several cases of the surgical treatment of tumoral calcinosis have been reported, the present case is unique in that multiple ectopic calcifications in subcutaneous tissues were found in a hemodialysis patient who had been operated on a total of five times within a period of 1.5 years. Methods A hemodialysis 60-year-old male presented with multiple tumor-like ectopic calcifications bilateral in the shoulders, right buttock and right thigh. He had been operated on a total of five times within a period of 1.5 years; the operations included a subtotal parathyroidectomy with parathyroid autotransplantation in the right forearm. Results Complete excisions of the ectopic calcifications were performed in the left shoulder, right buttock and right thigh, without signs of recurrence in the same sites at follow-up. Incomplete excision of the ectopic calcification in the right shoulder resulted in recurrence in the same site, and the patient was operated on two more times 1.5 years following the initial surgery. Subtotal parathyroidectomy with parathyroid autotransplantation decreased serum levels of PTH, but the levels of serum calcium and phosphorus remained unchanged post-surgery, which appeared not to inhibit the recurrence of ectopic calcification in patients with CRF. Conclusions If conservative therapy failed, then early and complete surgical excision may be a good therapeutic option.