Construction of a prognostic model based on genome-wide methylation analysis of miRNAs for hepatocellular carcinoma.

Aim: Using the methylation level of miRNA genes to develop a prognostic model for patients with hepatocellular carcinoma (HCC). Materials & methods: least absolute shrinkage and selection operator and multivariate Cox regression analyses were performed to develop a prognostic model. One miRNA in the model was selected for verification. Results: A prognostic model was developed using eight miRNAs. The areas under the curve for predicting overall survival at 1, 3 and 5 years were 0.75, 0.81 and 0.81. miR-223 was found to be hypomethylated in 160 HCC tissues, and its methylation level was associated with Barcelona Clinic Liver Cancer stages and the prognosis of patients with HCC. Conclusion: The prognostic model based on miRNA methylation levels has the capability to partially forecast the prognosis of patients with HCC.

Comprehensive multi-omics analysis of tryptophan metabolism-related gene expression signature to predict prognosis in gastric cancer.

Introduction: The 5-year survival of gastric cancer (GC) patients with advanced stage remains poor. Some evidence has indicated that tryptophan metabolism may induce cancer progression through immunosuppressive responses and promote the malignancy of cancer cells. The role of tryptophan and its metabolism should be explored for an in-depth understanding of molecular mechanisms during GC development. Material and methods: We utilized the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) dataset to screen tryptophan metabolism-associated genes via single sample gene set enrichment analysis (ssGSEA) and correlation analysis. Consensus clustering analysis was employed to construct different molecular subtypes. Most common differentially expressed genes (DEGs) were determined from the molecular subtypes. Univariate cox analysis as well as lasso were performed to establish a tryptophan metabolism-associated gene signature. Gene Set Enrichment Analysis (GSEA) was utilized to evaluate signaling pathways. ESTIMATE, ssGSEA, and TIDE were used for the evaluation of the gastric tumor microenvironment. Results: Two tryptophan metabolism-associated gene molecular subtypes were constructed. Compared to the C2 subtype, the C1 subtype showed better prognosis with increased CD4 positive memory T cells as well as activated dendritic cells (DCs) infiltration and suppressed M2-phenotype macrophages inside the tumor microenvironment. The immune checkpoint was downregulated in the C1 subtype. A total of eight key genes, EFNA3, GPX3, RGS2, CXCR4, SGCE, ADH4, CST2, and GPC3, were screened for the establishment of a prognostic risk model. Conclusion: This study concluded that the tryptophan metabolism-associated genes can be applied in GC prognostic prediction. The risk model established in the current study was highly accurate in GC survival prediction.

Temporal trends in surgery for Crohn's disease: a ten-year single-center retrospective study.

PURPOSE: Crohn's disease (CD) is a chronic inflammatory bowel disease that requires surgery in many cases. The aim of this article is to present the experience of a referral center regarding surgical interventions for CD, while also exploring the transformations that have occurred over 10 years. METHODS: The data of patients underwent abdominal surgery for CD between 2013 and 2022 were collected prospectively. Data were compared between two periods (2013-2017 and 2018-2022). Temporal trends were assessed with the Mann-Kendall trend test. RESULTS: A total of 1059 individuals underwent 1176 surgical procedures, of which 67.1% were male. The median age of patients at the time of surgery was 36.0 years, and an overall increasing trend was observed in surgical volume (z = 3.04; p = 0.002). The proportion of patients treated with biologics increased from the first period (2013-2017) to the second (2018-2022), rising from 19.2% to 33.5% (p < 0.001). In the second stage, the proportion of patients who underwent surgery for abscesses or fistulas increased (47.8% vs. 40.0%, p = 0.028), while the percentage of emergency surgeries declined (3.0% vs. 7.1%, p = 0.001). Furthermore, there was a rise in the proportion of laparoscopic surgeries (76.5% vs. 63.7%, p < 0.001), coupled with a decrease in stoma rates (15.4% vs. 30.5%, p < 0.001) and postoperative complications (23.0% vs. 30.5%, p = 0.007). CONCLUSION: The frequency of biologics use in CD surgery have increased over time, and the proportion of penetrating patients has grown. Minimally invasive surgical methods have become the norm, and surgical outcomes have markedly enhanced, evidenced by a substantial reduction in both stoma rates and complication rates.

Predicting the Clinical Outcome of Triple-Negative Breast Cancer Based on the Gene Expression Characteristics of Necroptosis and Different Molecular Subtypes.

Necroptosis, a kind of programmed necrotic cell apoptosis, is the gatekeeper for the host to defend against the invasion of pathogens. It helps to regulate different biological processes regarding human cancer. Nevertheless, studies that determine the impact of death on triple-negative breast cancer (TNBC) are scarce. Therefore, this paper has comprehensively examined the expression as well as clinical significance of necroptosis in TNBC. ConsensusClusterPlus was used to establish a stable molecular classification that used the expression regarding the necroptosis-linked genes. The clinical and immune characteristics of different subclasses were evaluated. Then, the weighted gene coexpression network analysis (WGCNA) assisted in determining key modules, and we selected the genes exhibiting obvious association with necroptosis prognosis through the relationship with prognosis. The univariate Cox regression analysis together with least absolute shrinkage and selection operator (LASSO) techniques served for the construction of the necroptosis-related prognostic risk score (NPRS) model, and the pathway characteristics of NPRS model grouping were further studied. Finally, the NPRS, taking into account the clinicopathological features, used the decision tree model for enhancing the prognostic model as well as the survival prediction. First, two stable molecular subtypes with different prognosis and immune characteristics were identified using necroptosis marker genes. Then, the key modules were identified, and 10 genes significantly related to the prognosis of necroptosis were selected. Then, the clinical prognostic model of NPRS was developed considering the prognosis-linked necroptosis genes. Finally, the NPRS model, taking into account the clinicopathological features, adopted the decision tree model for enhancing the prognostic model as well as the survival prediction. Herein, two new molecular subgroups considering necroptosis-linked genes are proposed, and an NPRS model composed of 10 genes is developed, which maybe assist in the personalized treatment and clinical treatment guidance of TNBC patients.

Insight into the history and trends of surgical simulation training in education: a bibliometric analysis.

BACKGROUND: Surgical simulation training enables surgeons to acquire clinical experience or skills from the operating room to the simulation environment. Historically, it has changed with advances in science and technology. Moreover, no previous study has analyzed this field from the bibliometric analysis dimension. The study aimed to review changes in surgical simulation training worldwide using bibliometric software. MATERIALS AND METHODS: Two searches were performed on the core collection database, Web of Science, regarding data from 1991 to the end of 2020 using three topic words (surgery, training, and simulation). From 1 January 2000, to 15 May 2022, the keyword 'robotic' was added for the hotspot exploration. The data were chiefly analyzed by publication date, country, author(s), and keywords using bibliometric software. RESULTS: A total of 5285 articles were initially analyzed, from which it was clear that laparoscopic skill, three-dimensional printing, and virtual reality were the main focuses during those study periods. Subsequently, 348 publications on robotic surgery training were identified. CONCLUSION: This study systematically summarizes the current status in the field of surgical simulation training and provides insights into the research focuses and future hotspot in a global context.

Identification and development of a novel risk model based on cuproptosis-associated RNA methylation regulators for predicting prognosis and characterizing immune status in hepatocellular carcinoma.

BACKGROUND: Cuproptosis, a novel cell death caused by excess copper, is quite obscure in hepatocellular carcinoma (HCC) and needs more investigation. METHODS: RNA-seq and clinical data of HCC patients TCGA database were analyzed to establish a predictive model through LASSO Cox regression analysis. External dataset ICGC was used for the verification. GSEA and CIBERSORT were applied to investigate the molecular mechanisms and immune microenvironment of HCC. Cuproptosis induced by elesclomol was confirmed via various in vitro experiments. The expression of prognostic genes was verified in HCC tissues using qRT-PCR analysis. RESULTS: Initially, 18 cuproptosis-associated RNA methylation regulators (CARMRs) were selected for prognostic analysis. A nine-gene signature was created by applying the LASSO Cox regression method. Survival and ROC assays were carried out to validate the model using TCGA and ICGC database. Moreover, there exhibited obvious differences in drug sensitivity in terms of common drugs. A higher tumor mutation burden was shown in the high-risk group. Additionally, significant discrepancies were found between the two groups in metabolic pathways and RNA processing via GSEA analysis. Meanwhile, CIBERSORT analysis indicated different infiltrating levels of various immune cells between the two groups. Elesclomol treatment caused a unique form of programmed cell death accompanied by loss of lipoylated mitochondrial proteins and Fe-S cluster protein. The results of qRT-PCR indicated that most prognostic genes were differentially expressed in the HCC tissues. CONCLUSION: Overall, our predictive signature displayed potential value in the prediction of overall survival of HCC patients and might provide valuable clues for personalized therapies.

Usefulness of the estimation of physiologic ability and surgical stress (E-PASS) system for prediction of complication and prognosis in hepatocellular carcinoma patients after hepatectomy.

Background: Estimation of physiologic ability and surgical stress (E-PASS) system was verified in predicting postoperative complications or mortality in many surgical operations. This research aimed to investigate whether the E-PASS system could predict postoperative complications and was related with long-term prognosis in primary hepatocellular carcinoma (HCC) patients. Methods: A total of 236 HCC patients who underwent liver resection were collected in this study. We performed univariate analyses to determine the potential risk factors for complications after hepatectomy. The potential independent risk factors were then included in the logistic regression for multivariable analysis. The optimal cutoff value of Comprehensive Risk Score (CRS) was identified by a receiver operating characteristic (ROC) curve. Based on this value, the patients were divided into two groups to investigate the relation between CRS with postoperative complications. The relation between CRS and overall survival (OS) or recurrence-free survival (RFS) was analyzed further in these two groups. Results: Postoperative complications occurred in 79 patients. Multivariable analysis suggested that CRS was independent factor for predicting postoperative complications (P<0.001). The optimal CRS cutoff value in our study was 0.126. Patients with high Preoperative Risk Score (PRS) had a higher rate of postoperative complications occurrence, both major and mild complications (P<0.001). Our study showed that HCC patients with higher CRS had poorer survival prognosis [hazard ratio (HR): 3.735, 95% confidence interval (CI): 1.200-11.631, P=0.023]. The 3-year OS rate of high CRS group (CRS ≥0.126) and low CRS group (CRS <0.126) were 66.2% vs. 84.8% (P<0.001), respectively. Conclusions: For HCC patients after liver resection, E-PASS was an effective predictive system for evaluating the risks of postoperative complications and may can predict prognosis in long term.

Hypomethylation status of miR-657 promoter region as biomarker for diagnosis of hepatocellular carcinoma: a retrospective study.

Background: The purpose of our study was to evaluate whether the methylation status of the miR-657 promoter region could be used as a biomarker for diagnosis of hepatocellular carcinoma (HCC), so as to find alternative biomarkers of early HCC detection. Methods: Cancerous and paired adjacent noncancerous tissues were collected from 160 patients who had been diagnosed with HCC by histopathology and received surgery. The methylation status of the miR-657 promoter region was measured using a MassARRAY Analyzer 4. Receiver operator characteristic (ROC) curve analysis was used to assess the effectiveness of miR-657 promoter region methylation status as a biomarker for diagnosis of HCC. Results: The mean methylation level of the miR-657 promoter region was significantly lower in cancerous tissues than in normal tissues of HCC patients (48.91%:67.04%, P<0.0001). ROC curve analysis revealed that the mean methylation level of the miR-657 promoter region could distinguish cancerous tissues from paired normal tissues of HCC patients (area under the curve: 0.847, P<0.001). Using 59.50% as the optimal cut-off, the sensitivity was 95.50% and the specificity was 70.01%. Conclusions: Methylation levels of the miR-657 promoter region were decreased in HCC patients and could be used as alternative and supplementary biomarkers for diagnosis of HCC.

Radiomics Analysis of Gd-EOB-DTPA Enhanced Hepatic MRI for Assessment of Functional Liver Reserve.

Rationale and Objectives To evaluate the effectiveness of radiomics analysis based on Gd-EOB-DTPA enhanced hepatic MRI for functional liver reserve assessment in HCC patients. Materials and Methods Radiomics features were extracted from Gd-EOB-DTPA enhanced MRI images in 60 HCC patients. Boruta algorithm was performed to select features associated with indocyanine green retention rate at 15 min (ICG R15). Prediction and classification model were built by performing Random Forest regression analysis. Pearson correlation analysis and AUC of ROC were used to assess performance of the two models. Results A total of 165 radiomics features were extracted. Six radiomics features were selected to build the prediction model. A Predicted value of ICG R15 for each patient was calculated by the prediction model. Pearson correlation analysis revealed that predicted values were significantly associated with actual values of ICG R15 (R value = 0.90, p < 0.001). Nine radiomics features were selected to build the classification model. AUC of ROC revealed favorable performance of the classification model for identifying patients with ICG R15 <10% (AUC: 0.906, 95%CI: 0.900-0.913), <15% (AUC: 0.954, 95%CI: 0.950-0.958), and <20% (AUC: 0.996, 95%CI: 0.995-0.996). Conclusion Radiomics analysis of Gd-EOB-DTPA enhanced hepatic MRI can be used for assessment of functional liver reserve in HCC patients.

The Estimation of Physiologic Ability and Surgical Stress (E-PASS) model as a predictor of postoperative complications and mortality after digestive surgeries: a meta-analysis and systematic review.

BACKGROUND: Conflicting results exist about the usefulness of the Estimation of Physiologic Ability and Surgical Stress (E-PASS) model in patients undergoing digestive surgeries. Thus, this study aims to analyze and evaluate the E-PASS model for predicting postoperative complications and mortality. METHODS: A literature search strategy for "E-PASS" was carried out in PubMed, Embase, Google Scholar, Ovid, and Cochrane databases for studies published before November 2020. "E-PASS" or "Estimation of Physiologic Ability and Surgical Stress" were used as the search terms in all databases, and a total of 20 published English language studies with available data relating to digestive surgery were selected for this study. Clinical data and indices including preoperative risk score (PRS), surgical stress score (SSS), comprehensive risk score (CRS), postoperative complications, mortality, and overall survival (OS) were collected. Meta-analyses of heterogeneity were performed using Review Manager version 5.3 and STATA 14.0. RESULTS: Twenty studies with 9,136 patients were included in our meta-analysis. Using a random-effects model, the indices of the E-PASS model in patients with postoperative complications were significantly greater than those in patients without complications [PRS: 95% confidence interval (CI): 0.14-1.50; SSS: 95% CI: 0.28-1.06; CRS: 95% CI: 048-1.49]. Moreover, patient morbidity and mortality were associated with a higher CRS (morbidity: 95% CI: 2.17-6.29; mortality: 95% CI: 1.57-4.78), while subgroup analyses showed that a high CRS in the elderly was related to increased morbidity (95% CI: 1.57-4.78) without heterogeneity. In addition, we found that a high E-PASS CRS was significantly associated with shorter OS after digestive surgery (95% CI: 1.24-5.41). DISCUSSION: The higher CRS score in the E-PASS model accompanies with many postoperative complications, increased mortality and shorter OS. Collectively, the E-PASS model is a convenient and effective risk assessment for patients undergoing digestive surgeries. More stringently designed studies are expected to develop better estimates of the application value of this model in digestive surgeries.

The Preoperative Prognostic Nutritional Index in Hepatocellular Carcinoma After Curative Hepatectomy: A Retrospective Cohort Study and Meta-Analysis.

OBJECTIVE: Conflicting results existed about the role of prognostic nutritional index (PNI) for hepatocellular carcinoma (HCC) patients who received curative hepatectomy. The aim of this study is to identify the predictive capacity of PNI for survival after hepatectomy. METHODS: Preoperative PNI, neutrophil-to-lymphocyte ratio (NLR), tumor feature and clinical information of 187 patients with HCC from Sir Run Run Shaw hospital were evaluated. We also conducted a meta-analysis of seven cohort studies. RESULTS: Our study showed that HCC patients with a low PNI of <45 had a poor recurrence-free survival (RFS) rate (hazard ratio [HR] 1.762, 95% confidence interval [CI] 1.066-2.911, p = 0.027, respectively). The 5-year OS and RFS rates of the high PNI (≥45) vs low PNI (<45) were 76.7% vs 50.1% (p = 0.001) and 47.0% vs 28.9% (p = 0.001), respectively. In HCC TNM I patients (n = 144), a low PNI remained an independent prognostic factor of OS and RFS (HR 2.305, 95% CI 1.008-5.268, p = 0.048; HR 2.122, 95% CI 1.149-3.920, p = 0.016). The 5-year OS and RFS rates of the high PNI vs low PNI were 81.3% vs 62.4% (p = 0.041) and 53.4% vs 45.6% (p = 0.013), respectively. In the pooled analysis, the data showed that a low PNI was significantly associated with poor OS and RFS (HR 2.27, 95% CI 1.03-4.07, p < 0.001 and HR 1.68, 95% CI 1.45-1.94, p < 0.001, respectively). CONCLUSIONS: The preoperative PNI was an independent prognostic factor for OS and RFS rates in HCC patients who received hepatectomy.

Safety and feasibility of laparoscopic liver resection for hepatocellular carcinoma with clinically significant portal hypertension: a propensity score-matched study.

BACKGROUND: The presence of clinically significant portal hypertension (CSPH) remains a relative contraindication to liver resection for patients with resectable hepatocellular carcinoma (HCC). The goal of this study was to explore whether a laparoscopic approach could extend the indications for hepatectomy to patients with PH. METHOD: Patients who underwent laparoscopic liver resection (LLR) from February 2016 to September 2019 performed by a single medical team were included in this study. We analyzed the surgical and oncological outcomes between groups with and without CSPH before and after propensity score matching (PSM). RESULT: We enrolled 156 patients divided into two groups according to the presence (CSPH, n = 26) or absence (non-CSPH, n = 130) of CSPH. CSPH group was associated with more clinical signs of liver dysfunction (p < 0.05). After PSM (n = 48 patients), the CSPH group tended to have a longer postoperative hospital stay (p = 0.054); however, there was no difference in operation time (p = 0.329), blood loss volume (p = 0.392), transfusion rates (p = 0.701), rate of conversion to open surgery (p = 0.666), surgical margin (p = 0.306), surgical mortality (n = 0), or comprehensive complication index (p = 0.844) between the two groups. The median follow-up time for the entire cohort was 19.6 months (range 0.2-40.6 months). The 3-year overall survival rate was 62.9% in the CSPH group and 84.3% in the non-CSPH group (p = 0.1090), and results were similar after PSM (p = 0.5734). CONCLUSIONS: LLR is safe and feasible for HCC with PH. The introduction of minimally invasive surgery, represented by LLR, can appropriately expand the indications for hepatectomy.

Aberrant methylation status of SPG20 promoter in hepatocellular carcinoma: A potential tumor metastasis biomarker.

PURPOSE: The aim of this study is to analyze the methylation levels of SPG20 promotor region and explore the association between the methylation levels and clinical features in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: We collected paired of HCC and adjacent non-cancerous tissues (ANT) from 160 HCC patients and analyze the methylation levels through MassARRAY Analyzer 4. The statistical calculations were performed using SPSS version 22.0. Real-time-quantification PCR was performed to assess expression levels of SPG20 in HCC cell lines. Wound healing assay and transwell assay was used to measure cell migration capacity. RESULT: We found that mean methylation level of SPG20 in tumor tissues was significantly higher than that in ANT (7.3% vs. 16.2%, P<0.0013). There was a significantly negative correlation between expression level and methylation level of SPG20 (P<0.01). In addition, the methylation levels in HCC were correlated with age and HBV infection. Meanwhile, micro-satellite tumors (P = 0.016) and tumor number (P = 0.018) was found significantly associated with increased methylation levels of several CpG sites and the mean levels of SPG20 promotor in ANT. In addtion, the capacity of cell migration was significantly enhanced in SPG20 knock-down HCC cells. CONCLUSION: The hypermethylation status of SPG20 gene promoter is significantly associated with intra-hepatic metastasis and contribute to HCC metastasis.

Mesh-reinforced pancreaticojejunostomy versus conventional pancreaticojejunostomy after pancreaticoduodenectomy: a retrospective study of 126 patients.

BACKGROUND: Pancreatic fistula is a major cause of morbidity and mortality after pancreaticoduodenectomy. The aim of this study is to compare the safety and efficacy of a newly developed technique, namely mesh-reinforced pancreaticojejunostomy, in comparison with the conventional use of pancreaticojejunostomy after undergoing a pancreaticoduodenectomy. METHODS: Data was collected from regarding 126 consecutive patients, who underwent the mesh-reinforced pancreaticojejunostomy or conventional pancreaticojejunostomy, after standard pancreaticoduodenectomy by one group of surgeons, between the time period of 2005 and 2016. This data was collected retrospectively. Surgical parameters and perioperative outcomes were compared between these two groups. RESULTS: A total of 65 patients received mesh-reinforced pancreaticojejunostomy and 61 underwent conventional pancreaticojejunostomy. There were no substantial differences in surgical parameters, mortality, biliary leakage, delayed gastric emptying, gastrojejunostomy leakage, intra-abdominal fluid collection, postpancreatectomy hemorrhage, reoperation, and the total hospital costs between the two groups. Pancreatic fistula rate (15 versus 34%; p = 0.013), overall surgical morbidity (25 versus 43%; p = 0.032), and length of hospital stay (18 ± 9 versus 23 ± 12 days; p = 0.016) were significantly reduced after mesh-reinforced pancreaticojejunostomy. Multivariate analysis of the postoperative pancreatic fistula revealed that the independent factors that were highly associated with pancreatic fistula were a soft pancreatic texture and the type of conventional pancreaticojejunostomy. CONCLUSIONS: This retrospective single-center study showed that mesh-reinforced pancreaticojejunostomy appears to be a safe technique for pancreaticojejunostomy. It may reduce pancreatic fistula rate and surgical complications after pancreaticoduodenectomy. TRIAL REGISTRATION: This research is waivered from trial registration because it is a retrospective analysis of medical records.

Interplay between apoptosis and autophagy in colorectal cancer.

Autophagy and apoptosis are two pivotal mechanisms in mediating cell survival and death. Cross-talk of autophagy and apoptosis has been documented in the tumorigenesis and progression of cancer, while the interplay between the two pathways in colorectal cancer (CRC) has not yet been comprehensively summarized. In this study, we outlined the basis of apoptosis and autophagy machinery firstly, and then reviewed the recent evidence in cellular settings or animal studies regarding the interplay between them in CRC. In addition, several key factors that modulate the cross-talk between autophagy and apoptosis as well as its significance in clinical practice were discussed. Understanding of the interplay between the cell death mechanisms may benefit the translation of CRC treatment from basic research to clinical use.

Fibrin glue versus staple for mesh fixation in laparoscopic transabdominal preperitoneal repair of inguinal hernia: a meta-analysis and systematic review.

BACKGROUND: The aim of this study was to compare outcomes of mesh fixation using fibrin glue versus staple in laparoscopic transabdominal preperitoneal (TAPP) repair of inguinal hernia. METHODS AND PROCEDURES: Database searches were carried out in PubMed, Embase, Cochrane Library, Web of Science and Cochrane databases until February 2016 using specific search terms. Studies which compared fibrin glue and staple for mesh fixation in laparoscopic transabdominal preperitoneal repair of inguinal hernia were enrolled. Outcomes, including inguinal hernia recurrence, chronic inguinal pain, seroma or hematoma formation and operating time, were measured. RESULTS: Four randomized controlled trials (RCTs, 430 patients) and six non-randomized controlled trials (non-RCTs, 8637 patients) were analyzed. Meta-analysis of the four RCTs showed no significant difference in hernia recurrence (OR 2.10, 95 % CI 0.61, 7.22), seroma or hematoma formation (OR 0.55, 95 % CI 0.27, 1.14) and operating time (SMD 0.80, 95 % CI -0.34, 1.94). Similarly, there was no significant difference in most of the outcomes of the six non-RCTs. CONCLUSIONS: Our meta-analysis and systematic review shows that the use of fibrin glue fixation may provide an alternative approach to staple fixation in TAPP inguinal hernia repair without increasing the postoperative morbidity. Large-scale RCTs with long-term follow-up are still needed to further assess postoperative outcomes such as chronic pain and disease recurrence.

MicroRNAs in bladder cancer: expression profiles, biological functions, regulation, and clinical implications.

Bladder cancer (UBC) is a common cancer worldwide and has a high rate of recurrence and progression despite systemic therapy. The molecular mechanisms of UBC are not completely understood. MicroRNAs are noncoding RNA molecules of approximately 23 nucleotides that play important roles in multiple steps during the progression of UBC. Here, we review the expression profiles of miRNAs and their biological functions, regulation, and clinical implications in UBC. Either down-regulation or up-regulation of miRNAs occurs in UBC through epigenetic changes or defects of the biogenesis apparatus. Deregulation of miRNAs is involved in cell-cycle arrest, apoptosis, proliferation, metastasis, drug resistance, and other functions in UBC. A number of miRNAs, including urine miRNAs, have been associated with tumor type, stage, or patient survival, and miRNAs might be developed as diagnostic or prognostic markers. Better understanding of the roles of miRNAs in UBC will shed light on the molecular mechanisms of UBC.

MicroRNAs in gastric cancer metastasis.

Gastric cancer (GC) is common worldwide and has a high rate of metastasis. The underlying molecular mechanism of metastasis are not entirely clear. MicroRNAs (miRNAs) are small, non-coding RNA molecules that regulate gene expression post-transcriptionally and are reported to be involved in multiple steps of tumor metastasis. Clarifying their roles in GC metastasis will improve understanding of this disease. Here, we review the involvement of miRNAs in multiple steps of GC metastasis, including epithelial-mesenchymal transitions, anoikis, angiogenesis, invasion, and migration. The clinical application of miRNAs as prognostic biomarkers in GC is also discussed.