Low-carbohydrate diets and the risk of pancreatic cancer: a large prospective cohort study.

Low-carbohydrate diets have become a popular approach for weight loss in recent years. However, whether low-carbohydrate diets are associated with the risk of pancreatic cancer remains to be elucidated. Hence, we examined the association of low-carbohydrate diets with the risk of pancreatic cancer in a US population. A population-based cohort of 95 962 individuals was identified. A low-carbohydrate-diet score was calculated to quantify adherence to this dietary pattern, with higher scores indicating greater adherence. Cox regression was used to calculate risk estimate for the association of the low-carbohydrate-diet score with the risk of pancreatic cancer. Subgroup analysis was used to identify the potential effect modifiers. After an average follow-up of 8.87 years (875856.9 person-years), we documented a total of 351 pancreatic cancer cases. In the fully adjusted model, the highest versus the lowest quartiles of the overall low-carbohydrate-diet score were found to be associated with a reduced risk of pancreatic cancer (hazard ratioquartile 4 versus 1: 0.61; 95% confidence interval: 0.45, 0.82; Ptrend < 0.001). Subgroup analysis found that the inverse association of low-carbohydrate diets with the risk of pancreatic cancer was more pronounced in individuals aged ≥65 years than in those aged <65 years (Pinteraction = 0.015). Similar results were obtained for animal and vegetable low-carbohydrate-diet scores. In conclusion, low-carbohydrate diets, regardless of the type of protein and fat, are associated with a lower risk of pancreatic cancer in the US population, suggesting that adherence to low-carbohydrate diets may be beneficial for pancreatic cancer prevention. Future studies should validate our findings in other populations.

Comparison of clinicopathological traits and prognostic factors of hepatocellular carcinoma with and without cirrhotic background.

The difference of the patients bearing hepatocellular carcinoma (HCC) with and without cirrhosis at clinical level has not been completely determined. This study compared their differences in clinicopathological traits and prognostic factors for relapse-free survival (RFS) and overall survival (OS). Animal model was established to validate the result of clinical observation. As a result, 82 patients bearing HCC with no cirrhosis (HCC-NC) and 146 patients bearing HCC with cirrhosis (HCC-C) were included. HCC-NC exhibited shorter prothrombin time and higher plasma albumin than HCC-C. In HCC-NC, satellite nodule was an independent risk factor for OS, and high γ-glutamyl transpeptidase was an independent risk factor for RFS. In HCC-C, female sex was an independent risk factor for OS. Stratified analysis showed the OS and RFS of HCC-NC were better than HCC-C in conditions like without cancer embolus (in the portal vein or bile duct), without lymphadenopathy in hepatic portal, without satellite nodule and with small or high-differentiated tumor. Animal model analysis showed HCC-NC had a higher liver/body weight ratio, less tumor count and smaller max tumor volume than HCC-C. In conclusion, clinicopathological traits and risk factors influencing postoperative OS and RFS differed between patients with HCC-C and HCC-NC.

The bifunctional SDF-1-AnxA5 fusion protein protects cardiac function after myocardial infarction.

Stromal cell-derived factor-1 (SDF-1) is a well-characterized cytokine that protects heart from ischaemic injury. However, the beneficial effects of native SDF-1, in terms of promoting myocardial repair, are limited by its low concentration in the ischaemic myocardium. Annexin V (AnxA5) can precisely detect dead cells in vivo. As massive cardiomyocytes die after MI, we hypothesize that AnxA5 can be used as an anchor to carry SDF-1 to the ischaemic myocardium. In this study, we constructed a fusion protein consisting of SDF-1 and AnxA5 domains. The receptor competition assay revealed that SDF-1-AnxA5 had high binding affinity to SDF-1 receptor CXCR4. The treatment of SDF-1-AnxA5 could significantly promote phosphorylation of AKT and ERK and induce chemotactic response, angiogenesis and cell survival in vitro. The binding membrane assay and immunofluorescence revealed that AnxA5 domain had the ability to specifically recognize and bind to cells injured by hypoxia. Furthermore, SDF-1-AnxA5 administered via peripheral vein could accumulate at the infarcted myocardium in vivo. The treatment with SDF-1-AnxA5 attenuated cell apoptosis, enhanced angiogenesis, reduced infarcted size and improved cardiac function after mouse myocardial infarction. Our results suggest that the bifunctional SDF-1-AnxA5 can specifically bind to dead cells. The systemic administration of bifunctional SDF-1-AnxA5 effectively provides cardioprotection after myocardial infarction.

Effective prediction of postoperative complications for patients after open hepatectomy: a simplified scoring system based on perioperative parameters.

BACKGROUND: The aim of the study was to develop a scoring system for the prediction of postoperative complications of open hepatectomy. METHOD: All consecutive patients receiving open hepatectomy from 2015 to 2017 were included in the study. Univariate and multivariate analyses were used to confirm the risk factors for postoperative complications. Afterwards, a novel scoring system was developed to predict the postoperative complications. RESULTS: The study included a total of 207 patients. For the test dataset, multivariate analysis indicated that diabetes, scale of surgery, serum potassium, and blood loss versus body weight were independent risk factors of the postoperative complications. The area under the curve (AUC) of the novel scoring system we proposed for prediction of postoperative complications of hepatectomy was 0.803, which is comparable with the AUCs of previous scoring systems. Furthermore, in the validation dataset, the corresponding AUC of the new scoring system was 0.717. CONCLUSION: This novel and simplified scoring system can effectively predict the postoperative complications of open hepatectomy and could help identify patients who are at high risk of postoperative complications.

Identifying Differentially Expressed MicroRNAs Between Cirrhotic and Non-Cirrhotic Hepatocellular Carcinoma and Exploring Their Functions Using Bioinformatic Analysis.

BACKGROUND/AIMS: Few studies have been designed to directly investigate the exact mechanisms underlying the different phenotypes between cirrhotic and non-cirrhotic hepatocellular carcinoma (HCC). This study aimed to illuminate the incidence and developmental mechanisms for both types of HCC through differentially expressed microRNAs (miRNAs) using bioinformatic analysis. METHODS: The miRNA-seq data and clinical data of patients (from The Cancer Genome Atlas (TCGA) database) were utilized to determine differentially expressed miRNAs between cirrhotic and non-cirrhotic HCC. Afterwards, the function of the selected miRNAs was predicted with online tools. Furthermore, the miRNA expression and clinical significance were validated by external datasets and our experiment. RESULTS: The present study included 135 non-cirrhotic and 80 cirrhotic patients to find differentially expressed miRNAs. Among them, four miRNAs (mir-1296, mir-23c, mir-149, and mir-95) were finally selected for further validation and analysis. Correlation analysis found that two miRNAs are greatly associated with the non-cirrhotic HCC patients' clinical traits, such as the T, M, and N tumor stages. However, only mir-23c was associated with the cirrhotic HCC patients' tumor T and N stages. Furthermore, survival analysis revealed that increased mir-149 in non-cirrhotic HCC, patients' age and the existence of vessels in the tumor in cirrhotic HCC were independent risk factors for the patients' postoperative overall survival. Functional and interaction analyses also supported the notion that these miRNAs function through some pathways that influence the behavior of the HCC. These results are strongly supported by analysis of extra datasets and our experiment. CONCLUSIONS: The cirrhotic and non-cirrhotic HCC types involve differentially expressed miRNAs, which are correlated with distinctive pathological traits. To some extent, non-cirrhotic HCC seems more dependent on miRNA network regulation, but additional studies are needed to confirm this conclusion.

Effectiveness and safety of single-port versus multi-port laparoscopic surgery for treating liver diseases: a meta-analysis.

OBJECTIVE: To compare the effectiveness and safety of single-port versus multi-port laparoscopic surgery for treating liver diseases. METHODS: Several databases were systematically searched for randomized controlled trials, cohort studies, and case-control studies on the use of single-port versus multi-port laparoscopic surgery to treat liver diseases from their inception until March 24, 2016. The primary outcomes were the operative time, volume of intraoperative blood loss, rate of postoperative complications, median length of postoperative stay, recovery time of gastrointestinal function, volume of postoperative drainage, and postoperative drainage time. The study-specific effect sizes and their 95 % confidence interval were all combined to calculate the pooled value by using a random-effects model. RESULTS: A total of nine studies were included, which involved 277 patients. The total and subgroup data were combined by meta-analysis. This meta-analysis showed that single-port and multi-port laparoscopic liver surgery for treating liver diseases did not differ in terms of operative time (P = 0.48), rate of postoperative complications (P = 0.56), median length of postoperative stay (P = 0.80), and recovery time of gastrointestinal function (P = 0.54). For liver diseases, the single-port group exhibited a lower volume of intraoperative blood loss than that presented by the multi-port group (P = 0.0006). In the hepatic resection subgroup, a lower volume of intraoperative blood loss was noted in the single-port group (P < 0.0001). By contrast, in the hepatic cyst subgroup, the single-port group showed a higher volume of intraoperative blood loss (P = 0.02) but a shorter median length of postoperative stay (P = 0.02). The findings of the potential subgroup analysis in these outcomes were consistent with the total data. CONCLUSION: Compared with multi-port laparoscopic surgery, the single-port method showed comparable effectiveness and safety for the treatment of liver diseases in terms of current evidence.

Balloon-occluded retrograde transvenous obliteration versus transjugular intrahepatic portosystemic shunt for treatment of gastric varices due to portal hypertension: A meta-analysis.

BACKGROUND AND AIM: The aim of this study was to compare the feasibility and safety of both balloon-occluded retrograde transvenous obliteration (BRTO) versus transjugular intrahepatic portosystemic shunt (TIPS) for treatment of gastric varices due to portal hypertension through the method of meta-analysis. METHODS: PubMed, Embase, and Cochrane Library were searched for both randomized controlled trials and cohort studies concerning BRTO compared with TIPS in the treatment of gastric varices from their inception to April 26, 2015. The Cochrane network RevMan 5.3 software was used for statistic analysis. The primary markers that need to be evaluated contained technical success rate, hemostasis rate, incidence rate of postoperative rebleeding, incidence rate of hepatic encephalopathy, and postoperative procedure-related complication. Study-specific odds ratios (ORs) were combined to calculate pooled value by using random effects model. RESULTS: Five original studies were included in total. Meta-analysis showed that BRTO and TIPS had no difference in aspects of technical success rate (OR, 0.19; 95% confidence interval [CI], 0.03-1.08; P = 0.06), hemostasis rate (OR, 3.41; 95% CI, 0.33-35.40; P = 0.30), and incidence rate of postoperative procedure-related complication (OR, 1.98; 95% CI, 0.44-8.84; P = 0.37). However, BRTO had a lower incidence rate of post-operative rebleeding (OR, 0.27; 95% CI, 0.09-0.81; P = 0.02) and a lower incidence rate of postoperative encephalopathy (OR, 0.05; 95% CI, 0.02-0.13; P < 0.00001). CONCLUSIONS: Balloon-occluded retrograde transvenous obliteration was a technically feasible as well as a secure method for the treatment of gastric varices originated from portal hypertension. It may have the potential to be an alterative shunt approach of TIPS, when suitable patients selected.

High-intensity focused ultrasound versus transarterial chemoembolization for hepatocellular carcinoma: a meta-analysis.

PURPOSE: The application of high-intensity focused ultrasound (HIFU) in hepatocellular carcinoma (HCC) was promising. However, whether the effect of HIFU is comparable with that of transarterial chemoembolization (TACE) has not been determined. MATERIALS AND METHODS: PubMed, Embase, Cochrane Library, Web of Science, WanFang Data, CqVip, CNKI, and CBM databases were searched for randomized controlled trials (RCTs), cohort studies, and case-control studies. The methodological quality of each study was evaluated. When there is no statistical heterogeneity, the fixed effect model would be used to merge data. Otherwise, the random effect model would be utilized. Sensitivity analyses were conducted by excluding one study each time. Subgroup analyses were conducted based on age, sex, tumor number, relative number of the patients with Child-Pugh C grade in each group, the percentage of patients with Child-Pugh C grade in the whole study, and tumor load. Publication bias was evaluated by Egger's test and Begg's test. RESULTS: Six cohort studies including 188 patients from HIFU group and 224 patients from TACE group were obtained for further analysis. The meta-analysis suggested HIFU and TACE showed no differences in postoperative 1-year overall survival (OS) rate, tumor response (including complete response, partial response, stable disease, and progressive disease), and postoperative complications. Moreover, compared with TACE, HIFU showed higher postoperative 6-month and 2-year OS rates. Subgroup analyses, meta regression analysis and sensitivity analyses indicated the findings above were reliable. Additionally, no potential publication bias was detected. CONCLUSION: For HCC, when compared with TACE, HIFU might show comparable safety but better effect. Considering the limitations of current studies, more well-designed studies are needed to validate our conclusion.

VEGF/Nrp1/HIF-1α promotes proliferation of hepatocellular carcinoma through a positive feedback loop.

To investigate the role of neuropilin1 (Nrp1) in glucose metabolism and proliferation of hepatocellular carcinoma (HCC) cells and to analyze its mechanism of action. The CRISPR gene knockout technique was used to knock out the Nrp1 gene in two HCC cell lines. The effect of Nrp1 on the proliferation of HCC cells was assessed in the CCK8 assay and plate cloning assay. The expression levels of glucose consumption, lactate production, and essential proteins of the glycolytic pathway were detected to explore the effect of Nrp1 on glucose metabolism in HCC cells. Using CoCl2 to revert the expression of hypoxia inducible factor-1α (HIF-1α), the role of HIF-1α in the pro-HCC cell metabolism of Nrp1 were demonstrated. The protein synthesis inhibitor CHX and proteasome inhibitor MG-132 was used to analyze the molecular mechanism of action of Nrp1 on HIF-1α. The Kaplan-Meier method was used to calculate survival rates and plot survival curves. Based on the CCK8 assay and plate cloning assay, we found that Nrp1 knockout significantly inhibited the proliferation of HCC cells. Nrp1 inhibitor suppressed lactate production and glucose consumption in HCC cells. Knockout of Nrp1 decreased the expression of glycolytic pathway-related proteins and HIF-1α protein. Furthermore, by joint use of CoCl2 and NRP1 knockout, we confirmed that reverting HIF-1α expression could reverse the effect of Nrp1 knockout on HCC cell metabolism in vitro. Mechanistically, Nrp1 showed a close correlation with the stability of HIF-1α protein in protein stability assay. Finally, we revealed that high expression of Nrp1 in HCC tissues was associated with poor overall survival and disease-free survival of the patients. Nrp1 accelerates glycolysis and promotes proliferation of HCC by regulating HIF-1α protein stability and through the VEGF/Nrp1/HIF-1α positive feedback loop.

Microfibrillated cellulose-enhanced carboxymethyl chitosan/oxidized starch sponge for chronic diabetic wound repair.

Herein, a novel microfibrillated cellulose (MFC) reinforced natural polymer-based sponge composed of carboxymethyl chitosan (CMC) and oxidized starch (OS) with hemostatic, repairing-promoting, and antimicrobial performances was fabricated for chronic wound repair. When the content of MFC reached 1.2 wt%, the prepared sponge exhibited ultra-fast water or blood-trigged shape recovery property within 3 s. Moreover, sponge was functionally modified with silver nanoparticles (AgNPs) and recombinant humanized collagen type III (rhCol III). The AgNPs and rhCol III loaded sponge (A-Ag/III) could effectively kill a broad spectrum of pathogenic microbes, promote the proliferation and migration of L929 cells in vitro. Due to their erythrocyte-aggregating ability and positive-charge feature of CMC, the A-Ag/III displayed rapid hemostasis ability. Furthermore, the in vivo animal experiment demonstrated the A-Ag/III could promote wound repair by inhibiting inflammation, promoting angiogenesis, and cell proliferation.

Postoperative survival of extrahepatic and intrahepatic cholangiocarcinoma after surgery: a population-based cohort.

OBJECTIVES: The study was designed to clarify the difference between extrahepatic cholangiocarcinoma (ECC) and intrahepatic cholangiocarcinoma (ICC) in postoperative cancer-specific death. DESIGN: Patients diagnosed with ECC and ICC after surgery, who are identified from the Surveillance, Epidemiology and End Results programme, are eligible for this retrospective cohort study. SETTING: Survival between groups was compared using the traditional Kaplan-Meier method and the cumulative incidence function (CIF) method. Propensity score-matched (PSM) analysis was conducted to balance the differences in vital variables between groups. The HR and 95% CI for ECC relative to ICC were used to quantify the risk of death. Subgroup analysis was further used to evaluate the stability of the differences between groups. RESULTS: The study included 876 patients with ECC and 1194 patients with ICC. Before PSM, with the Kaplan-Meier method, postoperative overall survival and cancer-specific death for ECC were worse than those for ICC. However, with the CIF method, no difference in postoperative cancer-specific death was found. After PSM, all differences in the considered traits were balanced, and 173 pairs of patients were retained. Survival analysis found that there was no difference in postoperative all-cause death (Kaplan-Meier method, p=0.186) or cancer-specific death (Kaplan-Meier and CIF methods, p=0.500 and p=0.913, respectively), which was consistent with subgroup analysis. CONCLUSIONS: ECC and ICC showed no difference in postoperative cancer-specific death, both in the natural state and in multiple variable-matched conditions. TRIAL REGISTRATION NUMBER: researchregistry4175.

Transcatheter Arterial Chemoembolization in Combination With High-Intensity Focused Ultrasound for Intermediate and Advanced Hepatocellular Carcinoma: A Meta-Analysis.

Background: The study was conducted to explore whether high-intensity focused ultrasound (HIFU) can improve the effect of transcatheter arterial chemoembolization (TACE) in intermediate and advanced hepatocellular carcinoma (HCC). Methods: PubMed, Embase, Cochrane Library, Web of Science, Wanfang Data, CQVIP, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical (CBM) databases were searched for randomized controlled trials (RCTs) comparing the effect of TACE in combination with HIFU group (group A) to TACE alone group (group B) in treating intermediate and advanced HCC. The primary outcomes were overall survival (OS) rate and tumor response rate. The odds ratio (OR) and 95% confidence interval (CI) for each study were calculated and then pooled with fixed effects model or random effects model. Sensitivity analyses and subgroup analyses were conducted. A publication bias was also evaluated. Results: After literature selection, eleven RCTs involving 803 patients were included in this meta-analysis. This meta-analysis revealed that group A was associated with an increased 6-month OS rate (OR = 0.20), 12-month OS rate (OR = 0.23), 24-month OS rate (OR = 0.32), and overall response rate (WHO criterion, OR = 0.22; RECIST criterion, OR = 0.30). Furthermore, subgroup analyses showed no bias in the result. Given the limited number of studies that reported major complications, no additional meta-analysis of complication was conducted. Despite no special treatment, any complication following HIFU treatment was found to subside within 3-7 days. Conclusion: TACE in combination with HIFU is associated with increased OS and tumor response in intermediate and advanced HCC. Current evidence supports the use of HIFU after TACE treatment in intermediate and advanced HCC.

Dissolving microneedle-encapsulated drug-loaded nanoparticles and recombinant humanized collagen type III for the treatment of chronic wound via anti-inflammation and enhanced cell proliferation and angiogenesis.

Nowadays, diabetic chronic wounds impose a heavy burden on patients and the medical system. Persistent inflammation and poor tissue remodeling severely limit the healing of chronic wounds. For these issues, the first recombinant humanized collagen type III (rhCol III) and naproxen (Nap) loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticle incorporated hyaluronic acid (HA) microneedle (MN) was fabricated for diabetic chronic wound therapy. As the tailored rhCol III was synthesized based on the Gly483-Pro512 segment, which contained the highly adhesive fragments (GER, GEK) in the human collagen type III sequence, it possessed strong cell adhesion. The mechanical strength of the prepared MN was enough to overcome the tissue barrier of necrosis/hyperkeratosis in a minimally invasive way after being applied in wounds. Subsequently, rhCol III and Nap@PLGA nanoparticles were rapidly released to the wound site within a few minutes. The prepared MN possessed favourable biocompatibility and could effectively facilitate the proliferation and migration of fibroblasts and endothelial cells. Furthermore, the regenerative efficacy of the MN was evaluated in vivo using the diabetic rat full-thickness skin wound model. These results illustrated that the prepared MN could accelerate wound closure by reducing the inflammatory response and enhancing angiogenesis or collagen deposition, indicating their significant application value in wound dressings for chronic wound repair.

Effectiveness and safety of focused ultrasound ablation surgery compared with radiofrequency ablation in primary hepatocellular carcinoma treatment: a meta-analysis.

BACKGROUND: The effectiveness and safety of focused ultrasound ablation surgery (FUAS) for primary hepatocellular carcinoma (HCC) treatment has not been fully evaluated. This study analyzed the effectiveness and safety of FUAS compared to radiofrequency ablation (RFA). METHODS: Studies published before November 1, 2020, in the following databases were analyzed: PubMed, Embase, Cochrane Library, Web of Science, Wanfang Data, CqVip, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical (CBM) database. All publications were reviewed independently by two authors. Both randomized controlled trials (RCTs) and cohort studies examining the effectiveness and safety of FUAS and RFA were considered. RCTs and cohort studies' methodological quality were evaluated using the Cochrane collaboration tool and the Newcastle-Ottawa Scale, respectively. RESULTS: A total of 6,597 records were identified, from which 3 cohort studies were selected for quantitative synthesis. All studies had relatively high methodological quality. The meta-analysis indicated that FUAS and RFA had comparable 3-month overall survival (OS) rates [risk ratio (RR): 0.99, 95% confidence interval (CI): 0.86 to 1.14], 6-month OS rates (RR: 1.03, 95% CI: 0.82 to 1.29), and 1-year OS rates (RR: 0.96, 95% CI: 0.84 to 1.11). Also, individual studies reported that the tumor response (reflected by tumor response and tumor ablation rate) and posttreatment complications were comparable between patients treated with FUAS and patients treated with RFA. Due to the limited number of studies reporting tumor response and posttreatment complications, further meta-analyses could not be conducted. DISCUSSION: FUAS and RFA were comparable in terms of effectiveness and safety in the treatment of primary HCC. However, current evidence is limited, and more prospective RCTs are warranted to confirm these findings.

Prognostic and diagnostic value of SOX9 in cirrhotic and noncirrhotic hepatocellular carcinoma.

BACKGROUND: This study was designed to explore the prognostic and diagnostic value of Sex-Determining Region Y-Box 9 (SOX9) in cirrhotic hepatocellular carcinoma HCC (CHCC) and noncirrhotic hepatocellular carcinoma (NCHCC). METHODS: SOX9 tissue expression was detected using data from The Cancer Genome Atlas (TCGA) database and our cohort. The Kaplan-Meier method was used to analyze differences in survival between high/low SOX9 expression groups. Univariate analysis and multivariate analysis were used to identify independent risk factors associated with overall survival (OS). Receiver operating characteristic (ROC) curve and area under the curve (AUC) were utilized for evaluation of the diagnostic efficacy of SOX9. RESULTS: SOX9 was found to exhibit differential expression between HCC and adjacent normal tissues but not between CHCC and NCHCC, which was confirmed by RNA sequencing, quantitative real-time polymerase chain reaction and immunohistochemical staining. Kaplan-Meier survival analysis and multivariate analysis revealed that high SOX9 expression was closely related to the OS in NCHCC but not that in CHCC. In CHCC and NCHCC, SOX9 expression was positively associated with serum α-fetoprotein levels. The AUC of SOX9 in differentiating HCC and adjacent normal tissues in CHCC and NCHCC was 0.77 and 0.78, respectively, and no significant difference was found between them. CONCLUSIONS: High SOX9 expression may aid prognostic evaluation in NCHCC but not in CHCC. SOX9 expression was not different between CHCC and NCHCC, but it has reliable and comparable diagnostic value in both CHCC and NCHCC.

The influence of substrate stiffness on osteogenesis of vascular smooth muscle cells.

Vascular stiffening occurs with advanced age and under pathological conditions such as vascular calcification, during which the osteogenesis of smooth muscle cells (SMCs) plays a key role. However, whether the stiffness of cellular microenvironment influences osteogenic responses in vascular SMCs is not well understood. Here, we cultured SMCs on the poly(dimethylsiloxane) (PDMS) substrates with varying stiffness from 0.363 to 2.327 MPa. The cell osteogenic transdifferentiation was induced by ß-glycerophosphate. Our findings demonstrated that the extent of osteogenesis in SMCs varied with the substrate stiffness. On three substrate stiffness, cells on the intermediate one (0.909 MPa) showed the highest extent of the osteogenesis based on the expression of osteogenic markers and calcium deposition. Transforming growth factor-ß1 and autophagy were involved in this stiffness-dependent process. This work highlights the importance of substrate stiffness to the osteogenesis of vascular SMCs, giving new scientific information for understanding of SMCs-mediated vascular calcification and designing of vascular implants.

Epigenetic silencing of GCH1promotes hepatocellular carcinoma growth by activating superoxide anion-mediated ASK1/p38 signaling via inhibiting tetrahydrobiopterin de novo biosynthesis.

Metabolic reprogramming is a hallmark of cancer, including hepatocellular carcinoma (HCC). However, its role in HCC remains to be elucidated. Herein, we identified GTP cyclohydrolase 1 (GCH1), the first rate-limiting enzyme in tetrahydrobiopterin (BH4) de novo biosynthesis, as a novel metabolic regulator of HCC. GCH1 was frequently down-regulated in HCC tissues and cell lines by promoter methylation. Low GCH1 expression was associated with larger tumor size, increased tumor number, and worse prognosis in two independent cohorts of HCC patients. Functionally, GCH1 silencing promoted HCC growth in vitro and in vivo, while GCH1 overexpression exerted an opposite effect. The metabolite BH4 inhibited HCC growth in vitro and in vivo. GCH1 silencing exerted its growth-promoting effect through directly inhibiting BH4 de novo biosynthesis. Mechanistically, GCH1 silencing activated ASK1/p38 signaling; pharmacological or genetic inhibition of ASK1 or p38 abolished GCH1 silencing-induced growth-promoting effect. Further mechanistic studies found that GCH1 silencing-induced BH4 reduction resulted in an increase of intracellular superoxide anion levels in a dose-dependent manner, which mediated the activation of ASK1/p38 signaling. Collectively, our study reveals that epigenetic silencing of GCH1 promotes HCC growth by activating superoxide anion-mediated ASK1/p38 signaling via inhibiting BH4 de novo biosynthesis, suggesting that targeting GCH1/BH4 pathway may be a promising therapeutic strategy to combat HCC.

miR-22 eluting cardiovascular stent based on a self-healable spongy coating inhibits in-stent restenosis.

The in-stent restenosis (IRS) after the percutaneous coronary intervention contributes to the major treatment failure of stent implantation. MicroRNAs have been revealed as powerful gene medicine to regulate endothelial cells (EC) and smooth muscle cells (SMC) in response to vascular injury, providing a promising therapeutic candidate to inhibit IRS. However, the controllable loading and eluting of hydrophilic bioactive microRNAs pose a challenge to current lipophilic stent coatings. Here, we developed a microRNA eluting cardiovascular stent via the self-healing encapsulation process based on an amphipathic poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC) triblock copolymer spongy network. The miR-22 was used as a model microRNA to regulate SMC. The dynamic porous coating realized the uniform and controllable loading of miR-22, reaching the highest dosage of 133 pmol cm-2. We demonstrated that the sustained release of miR-22 dramatically enhanced the contractile phenotype of SMC without interfering with the proliferation of EC, thus leading to the EC dominating growth at an EC/SMC ratio of 5.4. More importantly, the PCEC@miR-22 coated stents showed reduced inflammation, low switching of SMC phenotype, and low secretion of extracellular matrix, which significantly inhibited IRS. This work provides a simple and robust coating platform for the delivery of microRNAs on cardiovascular stent, which may extend to other combination medical devices, and facilitate practical application of bioactive agents in clinics.

Substrate stiffness differentially impacts autophagy of endothelial cells and smooth muscle cells.

Stiffening of blood vessels is one of the most important characteristics in the process of many cardiovascular pathologies such as atherosclerosis, angiosteosis, and vascular aging. Increased stiffness of the vascular extracellular matrix drives artery pathology and alters phenotypes of vascular cell. Understanding how substrate stiffness impacts vascular cell behaviors is of great importance to the biomaterial design in tissue engineering, regenerative medicine, and medical devices. Here we report that changing substrate stiffness has a significant impact on the autophagy of vascular endothelial cells (VECs) and smooth muscle cells (VSMCs). Interestingly, our findings demonstrate that, with the increase of substrate stiffness, the autophagy level of VECs and VSMCs showed differential changes: endothelial autophagy levels reduced, leading to the reductions in a range of gene expression associated with endothelial function; while, autophagy levels of VSMCs increased, showing a transition from contractile to the synthetic phenotype. We further demonstrate that, by inhibiting cell autophagy, the expressions of endothelial functional gene were further reduced and the expression of VSMC calponin increased, suggesting an important role of autophagy in response of the cells to the challenge of microenvironment stiffness changing. Although the underlying mechanism requires further study, this work highlights the relationship of substrate stiffness, autophagy, and vascular cell behaviors, and enlightening the design principles of surface stiffness of biomaterials in cardiovascular practical applications.

Biodegradable phosphorylcholine copolymer for cardiovascular stent coating.

Phosphorylcholine (PC) based polymer coatings with excellent biocompatibility have shown successful commercialization in drug-eluting stents. However, poor degradability represents a challenge in the application of biodegradable stents. Herein, a biodegradable phosphorylcholine copolymer is developed based on one-step radical ring-opening polymerization (RROP). This copolymer was synthesized by copolymerization of a PC unit, degradable ester (2-methylene-1,3-dioxepane, MDO) unit and non-degradable butyl methacrylate (BMA) unit, which showed ratio controllability by changing the monomer ratio during polymerization. We demonstrated that the copolymer with the ratio of 34% MDO, 19% MPC and 47% BMA could form a stable coating by ultrasonic spray, and showed good blood compatibility, anti-adhesion properties, biodegradability, and rapamycin eluting capacity. In vivo study revealed its promising application as a biodegradable stent coating. This work provides a facile path to add biodegradability into PC based polymers for further bio-applications.