N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer.

BACKGROUND: N6-methyladenosine (m6A) methylation modification exists in Epstein-Barr virus (EBV) primary infection, latency, and lytic reactivation. It also modifies EBV latent genes and lytic genes. EBV-associated gastric cancer (EBVaGC) is a distinctive molecular subtype of GC. We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC. AIM: To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC. METHODS: First, The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC (EBVnGC). Second, we identified Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment of m6A-related differentially expressed genes. We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment (TME). Finally, cell counting kit-8 cell proliferation test, transwell test, and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1 (IGFBP1) in EBVaGC cell lines. RESULTS: m6A methylation regulators were involved in the occurrence and development of EBVaGC. Compared with EBVnGC, the expression levels of m6A methylation regulators Wilms tumor 1-associated protein, RNA binding motif protein 15B, CBL proto-oncogene like 1, leucine rich pentatricopeptide repeat containing, heterogeneous nuclear ribonucleoprotein A2B1, IGFBP1, and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC (P < 0.05). The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher (P = 0.046). GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC. Compared with EBVnGC, the infiltration of activated CD4+ T cells, activated CD8+ T cells, monocytes, activated dendritic cells, and plasmacytoid dendritic cells were significantly upregulated in EBVaGC (P < 0.001). In EBVaGC, the expression level of proinflammatory factors interleukin (IL)-17, IL-21, and interferon-γ and immunosuppressive factor IL-10 were significantly increased (P < 0.05). In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line (SNU719) than in an EBVnGC cell line (AGS) (P < 0.05). IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719. Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS. CONCLUSION: m6A regulators could remodel the TME of EBVaGC, which is classified as an immune-inflamed phenotype and referred to as a "hot" tumor. Among these regulators, we demonstrated that IGFBP1 affected proliferation, migration, and apoptosis.

Suppression of MyD88 disturbs gut microbiota and activates the NLR pathway and hence fails to ameliorate DSS-induced colitis.

Background: Myeloid differentiation factor 88 (MyD88) is the core adaptor for Toll-like receptors defending against microbial invasion and initiating a downstream immune response during microbiota-host interaction. However, the role of MyD88 in the pathogenesis of inflammatory bowel disease is controversial. This study aims to investigate the impact of MyD88 on intestinal inflammation and the underlying mechanism. Methods: MyD88 knockout (MyD88-/-) mice and the MyD88 inhibitor (TJ-M2010-5) were used to investigate the impact of MyD88 on acute dextran sodium sulfate (DSS)-induced colitis. Disease activity index, colon length, histological score, and inflammatory cytokines were examined to evaluate the severity of colitis. RNA transcriptome analysis and 16S rDNA sequencing were used to detect the potential mechanism. Results: In an acute DSS-colitis model, the severity of colitis was not alleviated in MyD88-/- mice and TJ-M2010-5-treated mice, despite significantly lower levels of NF-κB activation being exhibited compared to control mice. Meanwhile, 16S rDNA sequencing and RNA transcriptome analysis revealed a higher abundance of intestinal Proteobacteria and an up-regulation of the nucleotide oligomerization domain-like receptors (NLRs) signaling pathway in colitis mice following MyD88 suppression. Further blockade of the NLRs signaling pathway or elimination of gut microbiota with broad-spectrum antibiotics in DSS-induced colitis mice treated with TJ-M2010-5 ameliorated the disease severity, which was not improved solely by MyD88 inhibition. After treatment with broad-spectrum antibiotics, downregulation of the NLR signaling pathway was observed. Conclusion: Our study suggests that the suppression of MyD88 might be associated with unfavorable changes in the composition of gut microbiota, leading to NLR-mediated immune activation and intestinal inflammation.

Global research trends and hotspots of Helicobacter pylori eradication based on clinical trial registration platforms: A cross-sectional analysis.

BACKGROUND: This study aimed to obtain an overview of clinical trials on Helicobacter pylori (H. pylori) eradication and analyze the global trends and hotspots in this field. METHODS: We collected the data from clinical trials focused on H. pylori eradication in the primary clinical trial registries from 2000 to 2022 in the world. Then we analyzed the research trends and hotspots in H. pylori eradication regimens in different regions at different periods. RESULTS: A total of 780 clinical trials were included, which were mainly conducted in Asia (682), followed by Europe (59), Africa (20), North America (16), South America (7), Oceania (2). The most active countries were China (343), Iran (140), South Korea (63), and Japan (73). "Bismuth-containing quadruple therapy (BQT)" was the most studied regimen (159, 20.38 %). Additionally, clinical trials focused on potassium-competitive acid blockers (P-CABs)-based therapy, probiotics, and high-dose dual therapy (HDDT) were constantly increasing. BQT received the most attention in China (26.53 %) and Iran (22.14 %), while it was tailored therapy in South Korea (23.29 %). P-CABs-based therapy was the main reseach hotspot in Japan (61.90 %). CONCLUSION: How to eradicate H. pylori infection has been a heated research topic. BQT, P-CABs-based therapy, probiotics, and HDDT attracted the most attention in recent years.

Determination of an Appropriate Endoscopic Monitoring Interval for Patients with Gastric Precancerous Conditions in China.

OBJECTIVE: Gastric precancerous conditions such as atrophic gastritis (AG) and intestinal metaplasia (IM) are considered independent risk factors for gastric cancer (GC). The suitable endoscopic monitoring interval is unclear when we attempt to prevent GC development. This study investigated the appropriate monitoring interval for AG/IM patients. METHODS: Totally, 957 AG/IM patients who satisfied the criteria for evaluation between 2010 and 2020 were included in the study. Univariate and multivariate analyses were used to determine the risk factors for progression to high-grade intraepithelial neoplasia (HGIN)/GC in AG/IM patients, and to determine an appropriate endoscopic monitoring scheme. RESULTS: During follow-up, 28 AG/IM patients developed gastric neoplasia lesions including gastric low-grade intraepithelial neoplasia (LGIN) (0.7%), HGIN (0.9%), and GC (1.3%). Multivariate analysis identified H. pylori infection (P=0.022) and extensive AG/IM lesions (P=0.002) as risk factors for HGIN/GC progression (P=0.025). CONCLUSION: In our study, HGIN/GC was present in 2.2% of AG/IM patients. In AG/IM patients with extensive lesions, a 1-2-year surveillance interval is recommended for early detection of HIGN/GC in AG/IM patients with extensive lesions.

Impact of body size on efficacy of high-dose dual therapy for Helicobacter pylori eradication.

BACKGROUND: High-dose dual therapy (HDDT) is an emerging and promising therapeutic regime for Helicobacter pylori (H. pylori) eradication. However, the pharmacokinetics of the components of HDDT, amoxicillin and proton pump inhibitor, are likely to be affected by body size. In this study, we aimed to find out the impact of body size on the efficacy of HDDT. METHODS: We collected the medical data of 385 treatment-naive patients infected with H. pylori who received HDDT (esomeprazole 20 mg and amoxicillin 750 mg four times daily) for 14 days from July 2020 to December 2021. The associations among the eradication efficacy, adverse events, and variables (sex, age, height, body weight, body mass index (BMI), body surface area (BSA), smoking, drinking, etc.) were analyzed respectively in our study. Among these factors, continuous variables were classified into categorical variables using the cut-off values which were calculated by receiver operating characteristic analysis. RESULTS: The eradication rate of HDDT was 89.9%. There were 55 (14.3%) patients who occurred adverse events during the treatment. Patients with height <170.5 cm, body weight <60.5 kg, BMI <20.55 kg/m2 , BSA <1.69 m2 had a higher eradication rate (92.1% vs. 84.0%, 93.1% vs. 86.8%, 96.0% vs. 87.8%, 93.4% vs. 84.8%, all p < .05). The multivariate analysis showed that BSA ≥1.69 m2 (OR 2.53, 95% CI: 1.28-4.99, p = .007) was the only independent predictor of eradication failure. CONCLUSION: HDDT could achieve better eradication efficacy in patients with small BSA. Clinicians should be aware of the impact of BSA on the H. pylori eradication rate and pay more attention to patients with large BSA.

The Pathway of China's Integrated Delivery System: Based on the Analysis of the Medical Consortium Policies.

With the deepening of China's health-care reform, an integrated delivery system has gradually emerged with the function of improving the efficiency of the health-care delivery system. For China's integrated delivery system, a medical consortium plays an important role in integrating public hospitals and primary care facilities. The first medical consortium policy issued after the COVID-19 pandemic apparently placed hope on accelerating the implementation of a medical consortium and tiered health-care delivery system. This paper illustrates the possible future pathway of China's medical consortium through retrospection of the 10-year process, changes of the series of policies, and characteristics of the policy issued in 2020. We considered that a fully integrated medical consortium would be a major phenomenon in China's medical industry, which would lead to the formation of a dualistic care pattern in China.

Analysis of Monitoring, Early Warning and Emergency Response System for New Major Infectious Diseases in China and Overseas.

In recent years, the impact of new major infectious diseases on people's normal life is becoming more and more frequent, which has brought great impact on people's life safety and social economy, especially the corona virus disease 2019, which has been sweeping the globe. Public health and disease prevention and control systems in different countries have different performances in response to the pandemic, but they all have exposed many shortcomings. Countries around the world urgently need to improve the monitoring, early warning and emergency response systems for new major infectious diseases. As the outpost and main part of medical rescue, the hospital urgently needs to establish a set of scientifically advanced emergency response mechanism that is suitable for the business process of the medical system and unified standards in order to improve the response efficiency and quality of emergency treatment.

Development Path and Urgency of further Strengthening Construction of Public Hospitals Based on Novel Coronavirus Pneumonia Treatment.

During the outbreak of novel coronavirus pneumonia (NCP) in Wuhan, public hospitals have played an important role in intensive care, case guidance and scheme optimization. At the same time, it also faces unprecedented challenges and tests. Based on the treatment of severe patients in Wuhan, combined with the treatment practice in Tongji Hospital affiliated to Tongji Medical College, Huazhong University of Science and Technology, this paper puts forward the urgency of further strengthening the construction of public hospitals, discusses the feasible path for promoting the development of public hospitals, so as to meet the growing medical needs of the people, improve the ability to respond to major public health emergencies, and effectively guarantee the safety of people's lives and the promotion of a healthy China construction.

Primary Cilia Blockage Promotes the Malignant Behaviors of Hepatocellular Carcinoma via Induction of Autophagy.

Primary cilia are organelles protruding from cell surface into environment that function in regulating cell cycle and modulating cilia-related signal. Primary ciliogenesis and autophagy play important roles in tumorigenesis. However, the functions and interactions between primary cilia and autophagy in hepatocellular carcinoma (HCC) have not been reported yet. Here, we aimed to investigate the relationship and function of primary cilia and autophagy in HCC. In vitro, we showed that serum starvation stimuli could trigger primary ciliogenesis in HCC cells. Blockage of primary ciliogenesis by IFT88 silencing enhanced the proliferation, migration, and invasion ability of HCC cells. In addition, inhibition of primary cilia could positively regulate autophagy. However, the proliferation, migration, and invasion ability which were promoted by IFT88 silencing could be partly reversed by inhibition of autophagy. In vivo, interference of primary cilia led to acceleration of tumor growth and increase of autophagic flux in xenograft HCC mouse models. Moreover, IFT88 high expression or ATG7 low expression in HCC tissues was correlated with longer survival time indicated by the Cancer Genome Atlas (TCGA) analysis. In conclusion, our study demonstrated that blockage of primary ciliogenesis by IFT88 silencing had protumor effects through induction of autophagy in HCC. These findings define a newly recognized role of primary cilia and autophagy in HCC.

The ASH1-miR-375-YWHAZ Signaling Axis Regulates Tumor Properties in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a worldwide malignance, and the underlying mechanisms of this disease are not fully elucidated. In this study, the existence and function of achaete-scute homolog-1 (ASH1)-miR-375-YWHAZ signaling axis in HCC were determined. Our experiments and the Cancer Genome Atlas (TCGA) sequencing data analyses showed that ASH1 and miR-375 were significantly downregulated, whereas YWHAZ was significantly upregulated in HCC. Furthermore, we found that ASH1 positively regulates miR-375, and miR-375 directly downregulates its target YWHAZ. Gain- and loss-of-function study demonstrated ASH1 and miR-375 function as tumor suppressors, whereas YWHAZ acts as an oncogene in HCC. Animal experiment indicated that YWHAZ small interfering RNAs (siRNAs) (si-YWHAZ) delivered by nanoliposomes could suppress the growth of hepatoma xenografts and was well tolerant by nude mice. Further studies revealed that YWHAZ was involved in several protein networks, such as cell autophagy, epithelial-mesenchymal transition (EMT), apoptosis, cell cycle, invasion, and migration. In addition, the patient group with ASH1-high-expression-miR-375-high-expression-YWHAZ-low-expression was correlated with a better clinical prognosis compared with the opposite expression group. In conclusion, we proved the existence of ASH1-miR-375-YWHAZ signaling axis and interpreted its important role in driving HCC tumor progression.

Celecoxib alleviates nonalcoholic fatty liver disease by restoring autophagic flux.

Nonalcoholic fatty liver disease (NAFLD) is a kind of liver lipid synthesis and degradation imbalance related with metabolic syndrome. Celecoxib shows the function of ameliorating NAFLD, but the underlying mechanisms remain unknown. Here, we discuss the possible mechanisms of celecoxib alleviating NAFLD by restoring autophagic flux. Lipids were accumulated in L02 cells treated with palmitate as well as SD rats fed with high-fat diet. Western blot showed that LC3 II/I was higher and p62 was lower on the early stage of steatosis while on the late stage both of them were higher, indicating that autophagic flux was activated on the early stage of steatosis, but blocked on the late stage. Rapamycin alleviated steatosis with activating autophagic flux while chloroquine aggravated steatosis with inhibiting autophagic flux. COX-2 siRNA and celecoxib were used to inhibit COX-2. Western blot and RFP-GFP-LC3 double fluorescence system indicated that celecoxib could ameliorate steatosis and restore autophagic flux in L02 cells treated with palmitate as well as SD rats fed with high-fat diet. In conclusion, celecoxib partially restores autophagic flux via downregulation of COX-2 and alleviates steatosis in vitro and in vivo.

The role of autophagy in hepatocellular carcinoma: friend or foe.

Autophagy is an evolutionarily conserved lysosome-dependent catabolic process which degrades cell's components in order to recycle substrates to exert optimally and adapt to tough circumstances. It is a critical cellular homeostatic mechanism with stress resistance, immunity, antiaging, and pro-tumor or anti-tumor effects. Among these, the role of autophagy in cancer is the most eye-catching that is not immutable but dynamic and highly complex. Basal autophagy acts as a tumor suppressor by maintaining genomic stability in normal cells. However, once a tumor is established, unbalanced autophagy will contribute to carcinoma cell survival under tumor microenvironment and in turn promote tumor growth and development. The dynamic role of autophagy can also apply on hepatocellular carcinoma (HCC). HCC is a highly malignant cancer with high morbidity and poor survival rate. Decline or overexpression of autophagic essential genes such as ATG7, ATG5 or Beclin 1 plays a key role in the occurrence and development of HCC but the exact mechanisms are still highly controversial. Signaling pathways or molecules involving in autophagy, for example PI3K/AKT/mTOR pathway, ERK/MAPK pathway, PERK pathway, p53, LncRNA PTENP1 (Long non-coding RNA PTENP1), microRNA-375 and so on, occupy an important position in the complex role of autophagy in HCC. Here, we discuss the dynamic role, the signaling pathways and the potential prognostic and therapy value of autophagy in HCC.

MiR-375 and Doxorubicin Co-delivered by Liposomes for Combination Therapy of Hepatocellular Carcinoma.

Doxorubicin (DOX) is one of the most frequently used anti-cancer drugs and the front line option for hepatocellular carcinoma (HCC) treatment. However, the clinical applications of DOX are restricted largely due to its toxicity and chemoresistance. Here, we report that miR-375 and DOX were co-delivered by liposomes (named L-miR-375/DOX-NPs) for combination therapy of HCC and drug resistance reversion of DOX. In vitro, L-miR-375/DOX-NPs could deliver DOX and miR-375 efficiently and simultaneously into HCC cells and ensure the successful release of mature miR-375 and DOX. Then, the released miR-375 suppressed the malignant hallmarks of HCC by significantly decreasing the expression of AEG-1, YAP1, and ATG7, while the released DOX evidently accelerated cell apoptosis and blocked cycle at a G2/M stage by activating the P53/Bax/Bcl-2, caspase-3, and P-JNK, P-P38 pathway. Furthermore, miR-375 dramatically inhibited drug resistance of DOX by reducing the expression of multidrug resistance gene 1 (MDR1). In vivo, L-miR-375/DOX-NPs exhibited enhanced anti-tumor efficiency in xenograft HCC mouse models with mild adverse effects compared with doxorubicin or miR-375 alone. In conclusion, our research demonstrated that L-miR-375/DOX-NPs had significant synergetic anti-tumor effects and added values in overcoming drug resistance, which may represent a promising approach for the therapy of HCC.

Traditional Chinese herbal extracts inducing autophagy as a novel approach in therapy of nonalcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver diseases around the world due to the modern sedentary and food-abundant lifestyle, which is characterized by excessive fat accumulation in the liver related with causes other than alcohol abuse. It is widely acknowledged that insulin resistance, dysfunctional lipid metabolism, endoplasmic reticulum stress, oxidative stress, inflammation, and apoptosis/necrosis may all contribute to NAFLD. Autophagy is a protective self-digestion of intracellular organelles, including lipid droplets (lipophagy), in response to stress to maintain homeostasis. Lipophagy is another pathway for lipid degradation besides lipolysis. It is reported that impaired autophagy also contributes to NAFLD. Some studies have suggested that the histological characteristics of NAFLD (steatosis, lobular inflammation, and peri-sinusoid fibrosis) might be improved by treatment with traditional Chinese herbal extracts, while autophagy may be induced. This review will provide insights into the characteristics of autophagy in NAFLD and the related role/mechanisms of autophagy induced by traditional Chinese herbal extracts such as resveratrol, Lycium barbarum polysaccharides, dioscin, bergamot polyphenol fraction, capsaicin, and garlic-derived S-allylmercaptocysteine, which may inhibit the progression of NAFLD. Regulation of autophagy/lipophagy with traditional Chinese herbal extracts may be a novel approach for treating NAFLD, and the molecular mechanisms should be elucidated further in the near future.

MiR-101 and doxorubicin codelivered by liposomes suppressing malignant properties of hepatocellular carcinoma.

MiR-101, an important tumor-suppressive microRNA (miRNA) in hepatocellular carcinoma (HCC), has been affirmed significantly downregulated in HCC and participated in promoting apoptosis, decreasing proliferation and invasiveness of HCC cells, as well as increasing sensitivity of chemotherapeutic drug. However, miR-101-based combination therapies with doxorubicin (DOX) are not reported yet. Recently, nanomaterials-based approaches, especially liposome formulations, have been approved for clinical use and seem to provide a great opportunity to codeliver therapeutic agents for cancer therapy. In this study, we have successfully prepared liposome (L) nanoparticles to efficiently deliver miR-101 and DOX to HCC cells simultaneously. The effects of codelivery system miR-101/doxorubicin liposome (miR-101/DOX-L) on tumor malignant phenotypes of HCC cells were evaluated through analyzing cell proliferation, colony formation, cell migration, cell invasion, cell apoptosis assay, and the expression of related genes. In subcutaneous xenografts developed by HCC cells, the inhibition of tumor growth was analyzed through gross morphology, growth curve, proliferation marker Ki-67, apoptosis signals, and the expression of related genes. These experiments demonstrated that miR-101/DOX-L inhibited tumor properties of liver cancer cells in vitro and in vivo through targeting correlative genes by combinatory role of miR-101 and DOX. In conclusion, our results indicated that liposome nanoparticle is a reliable delivery strategy to codeliver miR-101 and DOX simultaneously, and miR-101- and DOX-based combination therapy can result in significant synergetic antitumor effects in vivo and vitro.

Gold nanoparticles delivered miR-375 for treatment of hepatocellular carcinoma.

MiR-375 is a tumor suppressor miRNA that is downregulated in hepatocellular carcinoma (HCC). However, due to the lack of effective delivery strategies, miR-375 replacement as a therapy for HCC has not been investigated. In the present study, we have developed a straightforward strategy to deliver miR-375 into HCC cells by assembling miR-375 mimics on the surface of AuNPs and forming AuNP-miR-375 nanoparticles. AuNP-miR-375 exhibits high cellular uptake and preserves miR-375's activities to suppress cellular proliferation, migration/invasion, and colony formation, and to induce apoptosis in HCC cells. Furthermore, AuNP-delivered miR-375 efficiently downregulated its target genes through RNA interference. In primary and xenograft tumor mouse models, AuNP-miR-375 showed high tumor uptake, therapeutic efficacy, and no apparent toxicity to the host mice. In conclusion, our findings indicate that AuNPs is a reliable strategy to deliver miR-375 into HCC cells and tissue, and that AuNP-miR-375 has the potential in the clinic for treatment of unresectable HCC.

Patient safety education among chinese medical undergraduates: An empirical study.

Patient safety education is conducive to medical students' cognition on patient safety and to improvement of medical quality and safety. Developing patient safety education for medical students is more and more widely recognized by World Health Organization and countries all over the world. However, in China, patient safety courses aiming at medical students are relatively few, and there are few reports about the effect of patient safety courses. This paper explored the influence of patient safety curriculum on medical students' attitude to and knowledge of patient safety. The patient safety curriculum was carried out for 2011-grade undergraduates of Tongji Medical College, Huazhong University of Science and Technology. The students participated in the class according to free choice. After the curriculum, the information of gender, major, attended course, attitude toward patient safety, and knowledge of laws and regulations of the 2011-grade undergraduates were collected. After rejecting invalid questionnaires, the number of undergraduates that participated in the survey was 112 (61 students did not take part in the curriculum; 51 took part in). Chi-square test was applied to analyze patient safety education's influence on medical students' attitude to patient safety and their knowledge mastery situation. The influence of patient safety education on the attitude of medical students to patient safety was not significant, but that on their knowledge of patient safety was remarkable. No matter male or female, as compared with medical students who had not accepted patient safety education, they both had a better acquisition of knowledge after having this education (for male students: 95% CI, 4.556-106.238, P<0.001; for female students: 95% CI, 3.183-33.238, P<0.001). Students majoring in Western Medicine had a relatively better mastery of knowledge of patient safety after receiving patient safety education (95% CI, 6.267-76.271, P<0.001). Short-term patient safety education cannot change medical students' stereotyped cognition on matters related to patient safety, but it can effectively enhance their knowledge of laws and regulations of patient safety.

MiR-497 suppresses angiogenesis and metastasis of hepatocellular carcinoma by inhibiting VEGFA and AEG-1.

Hepatocellular carcinoma (HCC) is a worldwide malignance and displays marked vascular abnormalities and active metastasis. MicroRNAs (miRNAs) have been shown to play important roles in regulating tumor properties in cancer, however, whether miR-497 contributes to HCC angiogenesis or metastasis remains unclear. In this study, we found that miR-497 was significantly down-regulated in HCC tissue samples and cell lines. Gain-of-function and loss-of-function studies revealed that miR-497 could repress both the pro-angiogenic and metastatic ability of HCC cells. Subsequent investigations disclosed that miR-497 directly inhibited the 3'-untranslated regions (UTRs) of vascular endothelial growth factor A (VEGFA) and astrocyte elevated gene-1 (AEG-1). Furthermore, overexpression of these targets antagonized the function of miR-497. Based on nude mouse models, we demonstrated that overexpression of miR-497 significantly repressed microvessel densities in xenograft tumors and reduced pulmonary metastasis. In conclusion, our findings indicate that miR-497 downregulation contributes to angiogenesis and metastasis in HCC.

The emerging role of astrocyte-elevated gene-1 in hepatocellular carcinoma (Review).

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide, yet effective treatment for this disease is lacking. Thus, there is an urgent need to identify novel therapeutic targets for this dreadful disease. Numerous studies have established that overexpression of astrocyte-elevated gene-1 (AEG-1) is frequently observed in multiple types of cancers including HCC, and its expression levels are correlated with the stage and grade of the disease. Further studies revealed that AEG-1 plays a key role in several crucial aspects of HCC progression, including growth, transformation, cell survival, invasion, metastasis and chemoresistance. Moreover, AEG-1 overexpression activates the Wnt/ß-catenin, mitogen-actived protein kinase (MAPK), nuclear factor (NF)-κB, and PI3K/Akt signaling pathways, and promotes its downstream gene expression to facilitate malignant potential. Recently, transgenic mice with hepatocyte-specific expression of AEG-1 (Alb/AEG-1) and AEG-1-knockout mouse both revealed novel aspects of the functions of AEG-1 in an in vivo context. This review evaluates the multi-functions of AEG-1 and describes the major signaling pathways and molecular alterations regulated by AEG-1 in HCC, indicating its key roles and potential as a biomarker or significant target for the therapy of HCC.

The regulation of microRNA expression by DNA methylation in hepatocellular carcinoma.

UNLABELLED: Emerging evidence indicates that microRNAs (miRNAs) are often dysregulated and play a fundamental role in hepatocellular carcinoma (HCC). However, the mechanism underlying miRNA dysregulation is still elusive. In the present study, we adopted an integrated analysis strategy combining data from genome-wide methylated DNA immunoprecipitation chip and miRNA expression microarray to study the regulation of DNA methylation on miRNA expression in HCC. We first characterized 864 differentially methylated regions (DMRs) located in 236 miRNA regions between cancerous and normal hepatocytes in HCC. We observed that the occurrence of miRNA DNA hypomethylation was more common than its hypermethylation while miRNA DNA hypermethylation was usually found in CpG islands. Then through correlation analysis between miRNA methylation and expression data, we identified 10 dysregulated miRNAs under the potential regulation of DNA methylation in HCC. Five of them (miR-148a, miR-375, miR-195, miR-497 and miR-378) were in hypermethylation and down-regulation status, while another five (miR-106b, miR-25, miR-93, miR-23a and miR-27a) were in hypomethylation and up-regulation status in HCC. Bioinformatics analysis showed that miR-148a may form a negative feedback loop with its targets DNMT1 and DNMT3B and the expression of the miR-195/497 cluster may be affected not only by their hypermethylated promoter region but also by their hypermethylated transcription factors NEUROG2 and DDIT3. CONCLUSION: our preliminary data and bioinformatics analysis suggest that DNA methylation plays an important and complex role in the regulation of miRNA expression in HCC, which may provide insights into the pathogenesis of HCC and thus may be used for diagnosis and intervention.