Plastic Clamp Versus Conventional Surgical Dissection Technique in Pediatric Circumcision: A Systematic Review and Meta-Analysis.

PURPOSE: Phimosis is a common condition of the urinary system in children and often requires surgical treatment. However, the optimal method of circumcision for children has not been determined. We conducted a systematic review and meta-analysis to compare the safety and effectiveness of plastic clamp with conventional surgical circumcision in pediatric circumcision. METHODS: A literature search was carried out to compare the plastic clamp and conventional dissection technique in the pediatric population. The following search terms were used: "circumcision", "plastic clamp", "conventional", "plastibell", "children" and etc. Meta-analysis was used to pool and evaluate variables such as operative time, blood loss, wound infection, bleeding, edema, and total postoperative complications. RESULTS: The plastic clamp technique (PCT) was used in 10,412 of the 17,325 participants in the nine studies, while the conventional surgical dissection technique (CST) was used on 6913 patients. When compared to the CST approach, the PCT approach resulted in shorter operative times (mean difference (MD) -17.48, 95% CI -22 to -12.96; P < 0.001), less blood loss (MD -4.25, 95% CI -7.75 to -0.77; P = 0.02), and a higher incidence of postoperative edema (OR 2.33, 95% CI 1.34 to 4.08; P = 0.003). However, no significant difference was found in the incidence of postoperative complications, including wound infection and bleeding between PCT and CST. CONCLUSIONS: PCT is a safe and time-saving option in the pediatric population. However, this method appeared to have a significant greater rate of postoperative edema.

WNT signaling modulates chemoresistance to temozolomide in p53-mutant glioblastoma multiforme.

Glioblastoma multiforme (GBM) has been characterized by the high incidence, therapy tolerance and relapse. The molecular events controlling GBM resistant to chemotherapy temozolomide (TMZ) remain to be elusive. Here, we identified WNT signaling was amplified by TMZ and mediated drug response in GBM. We found O6-methylguanine DNA methyltransferase (MGMT) was redundant to WNT-mediated chemoresistance, which was highly associated with p53 mutation status. In GBM with p53 mutation, loss of function of p53 downregulated miR-34a expression, which represses transcription of WNT ligand 6 (WNT6) by directly binding to 3' UTR of WNT6 mRNA, leading to activation of WNT signaling, and the eventual WNT-mediated chemoresistance to TMZ. Combined treatment of TMZ with WNT inhibitor or miR34a mimic induced drug sensitivity of p53-mutant GBM cells and extended survival in xenograft mice in vivo. Our findings provide insight into understanding the molecular mechanism of GBM chemoresistance to TMZ and facilitating to develop novel treatment strategy to combat p53-mutant GBM by targeting miR-34a/WNT6 axis.

Prognostic factors of primary intrascrotal rhabdomyosarcoma in children: a population-based study.

PURPOSE: Primary intrascrotal rhabdomyosarcoma (RMS) is a rare and aggressive tumor. The purpose of this study was to investigate the prognostic factors of intrascrotal RMS in children. METHODS: All pediatric patients with intrascrotal RMS diagnosed between 2000 and 2018 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. To compare survival curves, the log-rank test was employed. A multivariate Cox proportional hazards model was developed to investigate the effect of each factor on overall survival (OS). A nomogram was created using the outcomes of the Cox regression model. RESULTS: A total of 102 pediatric patients with intrascrotal RMS were identified. Overall survival rates for all patients were 90.6% at 3-year and 87.2% at 5-year, respectively. Survival rates differed significantly by SEER stage and surgery; however, chemotherapy and removal of lymph nodes showed no significant difference. The outcome of Cox proportional hazard regression revealed that SEER stage and surgery were important independent predictors in this model. Furthermore, we developed a nomogram for predicting OS in pediatric intrascrotal RMS based on the Cox regression model. The risk of death increased with stage in patients. Additionally, patients who underwent surgery had a lower mortality risk than those who did not. CONCLUSIONS: Our findings show that SEER stage and surgery are the most important indicators of OS in children with intrascrotal RMS, providing critical epidemiological information for clinical therapy.

The requirement of the mitochondrial protein NDUFS8 for angiogenesis.

Mitochondria are important for the activation of endothelial cells and the process of angiogenesis. NDUFS8 (NADH:ubiquinone oxidoreductase core subunit S8) is a protein that plays a critical role in the function of mitochondrial Complex I. We aimed to investigate the potential involvement of NDUFS8 in angiogenesis. In human umbilical vein endothelial cells (HUVECs) and other endothelial cell types, we employed viral shRNA to silence NDUFS8 or employed the CRISPR/Cas9 method to knockout (KO) it, resulting in impaired mitochondrial functions in the endothelial cells, causing reduction in mitochondrial oxygen consumption and Complex I activity, decreased ATP production, mitochondrial depolarization, increased oxidative stress and reactive oxygen species (ROS) production, and enhanced lipid oxidation. Significantly, NDUFS8 silencing or KO hindered cell proliferation, migration, and capillary tube formation in cultured endothelial cells. In addition, there was a moderate increase in apoptosis within NDUFS8-depleted endothelial cells. Conversely, ectopic overexpression of NDUFS8 demonstrated a pro-angiogenic impact, enhancing cell proliferation, migration, and capillary tube formation in HUVECs and other endothelial cells. NDUFS8 is pivotal for Akt-mTOR cascade activation in endothelial cells. Depleting NDUFS8 inhibited Akt-mTOR activation, reversible with exogenous ATP in HUVECs. Conversely, NDUFS8 overexpression boosted Akt-mTOR activation. Furthermore, the inhibitory effects of NDUFS8 knockdown on cell proliferation, migration, and capillary tube formation were rescued by Akt re-activation via a constitutively-active Akt1. In vivo experiments using an endothelial-specific NDUFS8 shRNA adeno-associated virus (AAV), administered via intravitreous injection, revealed that endothelial knockdown of NDUFS8 inhibited retinal angiogenesis. ATP reduction, oxidative stress, and enhanced lipid oxidation were detected in mouse retinal tissues with endothelial knockdown of NDUFS8. Lastly, we observed an increase in NDUFS8 expression in retinal proliferative membrane tissues obtained from human patients with proliferative diabetic retinopathy. Our findings underscore the essential role of the mitochondrial protein NDUFS8 in regulating endothelial cell activation and angiogenesis.

Single-Cell Spatial Transcriptomics Unveils Platelet-Fueled Cycling Macrophages for Kidney Fibrosis.

With the increasing incidence of kidney diseases, there is an urgent need to develop therapeutic strategies to combat post-injury fibrosis. Immune cells, including platelets, play a pivotal role in this repair process, primarily through their released cytokines. However, the specific role of platelets in kidney injury and subsequent repair remains underexplored. Here, the detrimental role of platelets in renal recovery following ischemia/reperfusion injury and its contribution to acute kidney injury  to chronic kidney disease transition is aimed to investigated. In this study, it is shown that depleting platelets accelerates injury resolution and significantly reduces fibrosis. Employing advanced single-cell and spatial transcriptomic techniques, macrophages as the primary mediators modulated by platelet signals is identified. A novel subset of macrophages, termed "cycling M2", which exhibit an M2 phenotype combined with enhanced proliferative activity is uncovered. This subset emerges in the injured kidney during the resolution phase and is modulated by platelet-derived thrombospondin 1 (THBS1) signaling, acquiring profibrotic characteristics. Conversely, targeted inhibition of THBS1 markedly downregulates the cycling M2 macrophage, thereby mitigating fibrotic progression. Overall, this findings highlight the adverse role of platelet THBS1-boosted cycling M2 macrophages in renal injury repair and suggest platelet THBS1 as a promising therapeutic target for alleviating inflammation and kidney fibrosis.

PIK3R2 predicts poor outcomes for patients with melanoma and contributes to the malignant progression via PI3K/AKT/NF-κB axis.

BACKGROUND: Melanoma is an aggressive form of skin cancer worldwide. Phosphoinositide-3-kinase regulatory subunit 2 (PIK3R2) exerts carcinogenic roles in various tumors. So far, the function and mechanism of PIK3R2 in melanoma are not been fully clarified. OBJECTIVE: We aimed to clarify the role of PIK3R2 in melanoma. METHODS: PIK3R2 expressions in melanoma clinical tissues and melanoma cells were measured using quantitative real-time PCR and Western blot. In addition, PIK3R2 expressions in different tumor stages of melanoma were determined by immunohistochemistry assay. Meanwhile, PIK3R2 function was evaluated using loss or gain-of-function assays, Cell Counting Kit-8 assay, flow cytometry, and Transwell analysis. Furthermore, PIK3R2 mechanism in melanoma was assessed by a series of rescue experiments. RESULTS: PIK3R2 was highly expressed in melanoma tissues and cells, and PIK3R2 expressions were the highest in Stage IV. Functionally, PIK3R2 knockdown repressed melanoma cell proliferation, invasion, epithelial-mesenchymal transition, and facilitated cell apoptosis. Also, PIK3R2 overexpression produced an opposite trend. Mechanistically, PIK3R2 facilitated melanoma progression by activating PI3K/AKT/NF-κB pathway. Furthermore, PIK3R2 knockdown restrained the melanoma tumor growth in vivo. CONCLUSIONS: PIK3R2 aggravated melanoma by activating PI3K/AKT/NF-κB pathway, prompting that PIK3R2 might be a therapeutic target for melanoma.

Survival and Analysis of Prognostic Factors for Bladder Malignancies in Children and Adolescents: A Population-based Study.

OBJECTIVE: To explore the clinicopathological features and prognosis of pediatric patients with malignant bladder tumors in a population-based cohort. METHODS: The database Surveillance, Epidemiology, and End Results was used to evaluate all pediatric patients diagnosed with malignant bladder tumors between 1975 and 2018. The log-rank test was used to compare survival curves. Kaplan-Meier estimations were used to create survival curves based on various parameters. The Cox proportional hazards model was utilized to determine the factors that were independently related to mortality. RESULTS: A total of 263 children and adolescents with bladder malignancies were assessed. Papillary urothelial neoplasms of low malignant potential were the most frequent histologic subtype (35.1%), while embryonal rhabdomyosarcoma was more common during the first decade of life. Survival rates varied significantly by age at diagnosis, with older patients showing better outcomes. When compared to other subtypes, papillary urothelial neoplasms of low malignant potential had the highest overall survival rates (3- and 5-year were 99.2% and 98.3%, respectively). Multivariate analysis of the entire cohort showed that Surveillance, Epidemiology, and End Results stage and surgery were significant independent predictors of progression to disease-specific death in this model. CONCLUSION: Bladder malignancies are rare in children and adolescents. The prognosis for them varies. The localized stage was independently associated with superior survival and surgery could extend survival time.

Spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty for primary hypospadias repair.

INTRODUCTION: Neourethral covering is an essential technique for preventing complications such as fistula and glans dehiscence in hypospadias repairs. The spongioplasty has been reported for neourethral coverage about 20 years ago. However, reports of the outcome are limited. OBJECTIVE: This study aimed to retrospectively evaluate the short-term outcome of spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty (DIGU). METHODS: From December 2019 to December 2020, 50 patients with primary hypospadias (median age at surgery, 37 months; range, 10 months-12 years) were treated by a single pediatric urologist. The patients underwent spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty in single stage. The penile length, glans width, urethral plate width and length, and the location of the meatus of the patients were recorded preoperatively. The patients were followed up,complications noted, and postoperative uroflowmetries at the one-year follow-up time were evaluated. RESULTS: The average width of glans was 12.92 ± 1.86 mm. A minor penile curvature was observed in all patients (≤30°). The patients were followed up for 12-24 months, and 47 patients (94%) were free from complications. A neourethra formed with a slit-like meatus at the tip of the glans, and the urinary stream was straight. Three patients had coronal fistulae (3/50) and no glans dehiscence, and the mean ± SD Qmax of postoperative uroflowmetry was 8.13 ± 3.8 ml/s. DISCUSSION: This study estimated the short-term outcome of the DIGU covered using spongioplasty with Buck's fascia as the second layer in patients diagnosed with primary hypospadias with a relatively small glans (average width <14 mm). However, only a few reports emphasize spongioplasty with Buck's fascia as the second layer and the DIGU procedure performed on a relatively small glans. The major limitations of this study were its short follow-up time and the retrospective data collection. CONCLUSIONS: Dorsal inlay graft urethroplasty combined with spongioplasty with Buck's fascia as coverage is an effective procedure. In our study, this combination had good short-term outcomes for primary hypospadias repair.

USP18 enhances the resistance of BRAF-mutated melanoma cells to vemurafenib by stabilizing cGAS expression to induce cell autophagy.

This study aims to discern the possible molecular mechanism of the effect of ubiquitin-specific peptidase 18 (USP18) on the resistance to BRAF inhibitor vemurafenib in BRAF V600E mutant melanoma by regulating cyclic GMP-AMP synthase (cGAS). The cancer tissues of BRAF V600E mutant melanoma patients before and after vemurafenib treatment were collected, in which the protein expression of USP18 and cGAS was determined. A BRAF V600E mutant human melanoma cell line (A2058R) resistant to vemurafenib was constructed with its viability, apoptosis, and autophagy detected following overexpression and depletion assays of USP18 and cGAS. Xenografted tumors were transplanted into nude mice for in vivo validation. Bioinformatics analysis showed that the expression of cGAS was positively correlated with USP18 in melanoma, and USP18 was highly expressed in melanoma. The expression of cGAS and USP18 was up-regulated in cancer tissues of vemurafenib-resistant patients with BRAF V600E mutant melanoma. Knockdown of cGAS inhibited the resistance to vemurafenib in A2058R cells and the protective autophagy induced by vemurafenib in vitro. USP18 could deubiquitinate cGAS to promote its protein stability. In vivo experimentations confirmed that USP18 promoted vemurafenib-induced protective autophagy by stabilizing cGAS protein, which promoted resistance to vemurafenib in BRAF V600E mutant melanoma cells. Collectively, USP18 stabilizes cGAS protein expression through deubiquitination and induces autophagy of melanoma cells, thereby promoting the resistance to vemurafenib in BRAF V600E mutant melanoma.

Glutathione metabolism rewiring protects renal tubule cells against cisplatin-induced apoptosis and ferroptosis.

Renal proximal tubular cells are highly vulnerable to different types of assaults during filtration and reabsorption, leading to acute renal dysfunction and eventual chronic kidney diseases (CKD). The chemotherapeutic drug cisplatin elicits cytotoxicity causing renal tubular cell death, but its executing mechanisms of action are versatile and elusive. Here, we show that cisplatin induces renal tubular cell apoptosis and ferroptosis by disrupting glutathione (GSH) metabolism. Upon cisplatin treatment, GSH metabolism is impaired leading to GSH depletion as well as the execution of mitochondria-mediated apoptosis and lipid oxidation-related ferroptosis through activating IL6/JAK/STAT3 signaling. Inhibition of JAK/STAT3 signaling reversed cell apoptosis and ferroptosis in response to cisplatin induction. Using a cisplatin-induced acute kidney injury (CAKI) mouse model, we found that inhibition of JAK/STAT3 significantly mitigates cisplatin nephrotoxicity with a reduced level of serum BUN and creatinine as well as proximal tubular distortion. In addition, the GSH booster baicalein also reclaims cisplatin-induced renal tubular cell apoptosis and ferroptosis as well as the in vivo nephrotoxicity. In conclusion, cisplatin disrupts glutathione metabolism, leading to renal tubular cell apoptosis and ferroptosis. Rewiring glutathione metabolism represents a promising strategy for combating cisplatin nephrotoxicity.

Autophagy of OTUD5 destabilizes GPX4 to confer ferroptosis-dependent kidney injury.

Ferroptosis is an iron-dependent programmed cell death associated with severe kidney diseases, linked to decreased glutathione peroxidase 4 (GPX4). However, the spatial distribution of renal GPX4-mediated ferroptosis and the molecular events causing GPX4 reduction during ischemia-reperfusion (I/R) remain largely unknown. Using spatial transcriptomics, we identify that GPX4 is situated at the interface of the inner cortex and outer medulla, a hyperactive ferroptosis site post-I/R injury. We further discover OTU deubiquitinase 5 (OTUD5) as a GPX4-binding protein that confers ferroptosis resistance by stabilizing GPX4. During I/R, ferroptosis is induced by mTORC1-mediated autophagy, causing OTUD5 degradation and subsequent GPX4 decay. Functionally, OTUD5 deletion intensifies renal tubular cell ferroptosis and exacerbates acute kidney injury, while AAV-mediated OTUD5 delivery mitigates ferroptosis and promotes renal function recovery from I/R injury. Overall, this study highlights a new autophagy-dependent ferroptosis module: hypoxia/ischemia-induced OTUD5 autophagy triggers GPX4 degradation, offering a potential therapeutic avenue for I/R-related kidney diseases.

Explore the multitarget mechanism of tetrahydrocurcumin preventing on UV-induced photoaging mouse skin.

UV induced photoaging is the main external factor of skin aging. In this study, we tested the protective effects of tetrahydrocurcumin on UV-induced skin photoaging of KM mice and researched the multi-target mechanism through RNA sequencing technology. Mouse experiments show that tetrahydrocurcumin strongly changed in skin appearance, epidermal thickness, and wrinkle-related parameters in UV-irradiated mice. RNA-seq result show that we found 29 differentially expressed mRNA transcripts in UV mice relative to Ctrl rats (18 up-regulated and 11 down-regulated) and 7 significantly dysregulated mRNAs were obtained in the THC group compared to the UV group (1 up-regulated and 6 down-regulated), respectively. Spink7, Edn3, Stab2 may be the key target genes of tetrahydrocurcumin in preventing aging. Bioinformatics analysis shows that the response to muscle contraction and melanin biosynthetic GO term and Inflammation related pathway such as PPAR, MAPK would involve in effects of tetrahydrocurcumin. The results of this study indicated that tetrahydrocurcumin can improve the appearance through anti-inflammatory, improving extracellular matrix and inhibiting melanin production. It could be suggested as a protective measure in the prevention of UV-induced photoaging.

Long Non-Coding RNA CRNDE Functions as a Tumor Promoter by Modulating the ERK/MAPK Signaling Pathway in Neuroblastoma Cells.

OBJECTIVE: The long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) is considered a carcinogenic promoter in various human malignancies. However, the role and underlying mechanism of action of CRNDE during carcinogenesis in neuroblastoma remain unknown. METHODS: CRNDE transcript levels were detected in neuroblastoma tissues and adjacent normal tissues. The effects of CRNDE overexpression and knockdown on the viability of SH-SY5Y and SK-N-AS cells were determined using the Cell Counting Kit-8 (CCK-8) assay. Flow cytometry was performed to measure the role of CRNDE in apoptosis and the cell cycle in neuroblastoma cells. Moreover, the transwell assay was used to evaluate the role of CRNDE in the migration and invasion of tumor cells. The levels of ERK/MAPK pathway-related proteins were evaluated using western blotting. The in vivo role of CRNDE in tumor growth and apoptosis was evaluated in a xenograft mouse model of human neuroblastoma. RESULTS: The relative expression of CRNDE was significantly higher in neuroblastoma tissues than in the adjacent normal tissues. Moreover, knockdown of CRNDE inhibited tumor cell proliferation and induced apoptosis and cell cycle arrest, whereas elevation of CRNDE promoted cell growth and inhibited apoptosis in neuroblastoma cells. In addition, depletion of CRNDE suppressed migration and invasion, whereas overexpression of CRNDE enhanced the migratory and invasive potential of SH-SY5Y and SK-N-AS cells. At the mechanistic level, western blotting showed that CRNDE exerted its oncogenic role by affecting the ERK/MAPK signaling pathway. Furthermore, animal experiments confirmed that CRNDE promotes tumor growth and inhibits apoptosis in neuroblastoma in vivo. CONCLUSION: The present study revealed that CRNDE plays a critical role in the proliferation, apoptosis, migration, and invasion of neuroblastoma by altering the ERK/MAPK signaling pathway, representing a novel molecular target for the treatment of neuroblastoma.

A novel selective mitochondrial-targeted curcumin analog with remarkable cytotoxicity in glioma cells.

Naturally occurring polyphenol curcumin (4) or demethoxycurcumin (5) and their synthetic derivatives display promising anticancer activities. However, their further development is limited by low bioavailability and poor selectivity. Thus, a mitochondria-targeted compound 14 (DMC-TPP) was prepared in the present study by conjugating a triphenylphosphine moiety to the phenolic hydroxyl group of demethoxycurcumin to enhance its bioavailability and treatment efficacy. The in vitro biological experiments of DMC-TPP showed that it not only displayed higher cytotoxicity as compared with its parent compound 5, but also exhibited superior mitochondria accumulation ability. Glioma cells were more sensitive to DMC-TPP, which inhibited the proliferation of U251 cells with an IC50 of 0.42 µM. The mechanism studies showed that DMC-TPP triggers mitochondria-dependent apoptosis, caused by caspase activation, production of reactive oxygen species (ROS) and decrease of mitochondrial membrane potential (MMP). In addition, DMC-TPP efficiently inhibited cellular thioredoxin reductase, which contributed to its cytotoxicity. Significantly, DMC-TPP delayed tumor progression in a mouse xenograft model of human glioma cancer. Taken together, the potent in vitro and in vivo antitumor activity of DMC-TPP warrant further comprehensive evaluation as a novel anti-glioma agent.

ß-Elemene Triggers ROS-dependent Apoptosis in Glioblastoma Cells Through Suppressing STAT3 Signaling Pathway.

Glioblastoma is one of the most aggressive primary brain tumors with few treatment strategies. ß-Elemene is a sesquiterpene known to have broad spectrum antitumor activity against various cancers. However, the signaling pathways involved in ß-elemene induced apoptosis of glioblastoma cells remains poorly understood. In this study, we reported that ß-elemene exhibited antiproliferative activity on U87 and SHG-44 cells, and induced cell death through induction of apoptosis. Incubation of these cells with ß-elemene led to the activation of caspase-3 and generation of reactive oxygen species (ROS). Western blot assay showed that ß-elemene suppressed phosphorylation of STAT3, and subsequently down-regulated the activation of p-JAK2 and p-Src. Moreover, pre-incubation of cells with ROS inhibitor N-acetyl-L-cysteine (NAC) significantly reversed ß-elemene-mediated apoptosis effect and down-regulation of JAK2/Src-STAT3 signaling pathway. Overall, our findings implied that generation of ROS and suppression of STAT3 signaling pathway is critical for the apoptotic activity of ß-elemene in glioblastoma cells.

Carboplatin activates the cGAS-STING pathway by upregulating the TREX-1 (three prime repair exonuclease 1) expression in human melanoma.

Human melanoma is a highly aggressive type of cancer, causing significant mortalities despite the advances in treatment. Carboplatin is a cisplatin analog necessary for the treatment of various cancers and can also be used to treat human melanoma. We assessed the effects and mechanisms leading to inhibited proliferation and induced apoptosis of human melanoma after carboplatin therapy in vitro and in vivo. TREX1, cGAS/STING, and apoptotic protein expressions were determined through RT-qPCR and western blot assays. Cell proliferation was validated through MTT assays. The study used SK-MEL-1 and SK-HEP-1 tumor cell line inoculations along with carboplatin in nude mice to validate the results. The TREX1 levels were down-regulated in human melanoma cell lines. TREX1 overexpression-induced apoptosis and decreased proliferation in the human melanoma cell lines. TREX1 overexpression also activated the cGAS/STING pathway to induce apoptosis and decrease cell growth. Carboplatin activated TREX1, induced apoptosis, and decreased proliferation in the human melanoma cancerous cell lines. Finally, carboplatin reduced the in-vivo tumor size and weight. In conclusion, the study revealed that carboplatin activated TREX1 and cGAS/STING pathways to upregulate apoptosis. The work also provides in vitro and in vivo evidence to understand the effects of TREX overexpression on tumor suppression. Targeting of TREX1/cGAS/STING pathway could be an effective therapeutic alternative to human melanoma.

MiR-513c suppresses neuroblastoma cell migration, invasion, and proliferation through direct targeting glutaminase (GLS).

Neuroblastoma is a malignancy [corrected] of childhood and accounts for 7-10% of childhood cancers, leading to approximately 15% of pediatric cancer deaths. MicroRNAs (miRNAs) are a family of short (about 18-25 nucleotides), noncoding and single stranded endogenous RNAs, which complementarily bind to the 3' untranslated regions of their target genes. Recently, glutamine metabolism has been recognized as an important nutrition source for tumor cells, and hence targeting glutamine metabolism could benefit to development of anti-cancer agents. In this study, we investigate the roles of miR-513c in human neuroblastoma. We report miR-513c is significantly downregulated in human neuroblastoma tissues compared with their adjacent normal tissues. Moreover, miR-513c is significantly downregulated in neuroblastoma cell lines compared with normal neuroblast cells. Overexpression of miR-513c suppresses neuroblastoma cells' migration, invasion, and proliferation. We demonstrate the glutaminase (GLS) is a direct target of miR-513c in human neuroblastoma cells. In addition, we found restoration of GLS expression recovered the neuroblastoma cells' migration, invasion, and proliferation. In summary, this study illustrates a miR-513c mediated neuroblastoma cells suppression, providing a new aspect on the miRNA-based therapeutic approach for the treatments of neuroblastoma.

VEGF-Loaded Nanoparticle-Modified BAMAs Enhance Angiogenesis and Inhibit Graft Shrinkage in Tissue-Engineered Bladder.

Insufficient angiogenesis is a common problem in bladder tissue engineering and is believed to be a major factor responsible for graft shrinkage. In this study, we investigated the use of bladder acellular matrix allografts (BAMAs) modified with vascular endothelial growth factor (VEGF)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) for the long-term sustained release of VEGF to enhance blood supply and inhibit graft shrinkage in a rabbit model of bladder reconstruction. Rabbits underwent partial bladder cystectomy using a 2 × 3 cm BAMA modified with VEGF-loaded PLGA NPs in the experimental group, while no modification was used in the control. Histology and immunohistochemical analyses showed that urothelium, smooth muscle fibers and blood vessels were formed in both groups at 4 and 12 weeks postoperatively. The microvessel density in the experiment group was significantly higher than that in control and the contracture rate declined to 27%. In vitro functional experiments indicated that the characteristics of regenerated bladders were similar to native bladders. The VEGF release from BAMA in vivo was almost 83% within 3 months. Our data demonstrated the effectiveness of VEGF-loaded PLGA NPs-modified BAMAs to enhance neovascularization and solve the problems of insufficient angiogenesis and graft shrinkage associated with bladder tissue engineering.

A nanomedicine approach to effectively inhibit contracture during bladder acellular matrix allograft-induced bladder regeneration by sustained delivery of vascular endothelial growth factor.

Macroscopic evidence of contracture has been identified as a major issue during the regeneration process. We hypothesize that lack of angiogenesis is the primary cause of contracture and explore a nanomedicine approach to achieve sustained release of vascular endothelial growth factor (VEGF) to stimulate angiogenesis. We evaluate the efficacy of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) for long-term (3 months) sustained release of VEGF in bladder acellular matrix allografts (BAMA) in a swine model. We anticipate that the sustained release of VEGF could stimulate angiogenesis along the regeneration process and thereby inhibit contracture. Bladder was replaced with BAMA (5×5 cm), modified with PLGA NPs encapsulated with VEGF in a pig model. The time points chosen for sampling were 1, 2, 4, and 12 weeks. The regenerated areas were then measured to obtain the contracture rate, and the extent of revascularization was calculated using histological and morphological features. In the control group of animals, the bladder was replaced with only BAMA. The in vivo release of VEGF was evident for ∼3 months, achieving the goal of long-acting sustained release, and successfully promoted the regeneration of blood vessels and smooth muscle fibers. In addition, less collagen deposition was observed in the experimental group compared with control. Most importantly, the inhibition of contracture was highly significant, and the ultimate contracture rate decreased by ∼57% in the experimental group compared with control. In isolated strips analysis, there were no significant differences between BAMA-regenerated (either VEGF added or not) and autogenous bladder. BAMA modified with VEGF-loaded PLGA-NPs can sustainably release VEGF in vivo (>3 months) to stimulate angiogenesis leading to the inhibition of contracture. This is the first study to report a viable nanomedicine-based strategy to overcome contracture during bladder regeneration induced by BAMA. Furthermore, this study also confirms that insufficient angiogenesis plays a crucial role in the onset of contracture.