The biological role of extracellular vesicles in gastric cancer metastasis.

Gastric cancer (GC) is a tumor characterized by high incidence and mortality, with metastasis being the primary cause of poor prognosis. Extracellular vesicles (EVs) are an important intercellular communication medium. They contain bioactive substances such as proteins, nucleic acids, and lipids. EVs play a crucial biological role in the process of GC metastasis. Through mechanisms such as remodeling the tumor microenvironment (TME), immune suppression, promoting angiogenesis, and facilitating epithelial-mesenchymal transition (EMT) and mesothelial-mesenchymal transition (MMT), EVs promote invasion and metastasis in GC. Further exploration of the biological roles of EVs will contribute to our understanding of the mechanisms underlying GC metastasis and may provide novel targets and strategies for the diagnosis and treatment of GC. In this review, we summarize the mechanisms by which EVs influence GC metastasis from four aspects: remodeling the TME, modulating the immune system, influencing angiogenesis, and modulating the processes of EMT and MMT. Finally, we briefly summarized the organotropism of GC metastasis as well as the potential and limitations of EVs in GC.

Assessment of the efficacy and safety of carbon nanoparticles-guided lymph node dissection in gastric cancer surgery: a systematic review and meta-analysis.

BACKGROUND: To investigate the efficacy and safety of lymph nodes (LNs) dissection guided by carbon nanoparticles (CNs) in gastric cancer (GC) surgery. MATERIALS AND METHODS: We searched electronic databases such as PubMed, Web of Science, Embase, Cochrane Library, and Scopus for relevant articles up to September 2022 and collected all studies comparing the CNs group with blank controls group on the efficacy and safety of LN dissection in gastrectomy. A pooled analysis of the collected data was performed, including the number of retrieved LNs, the staining rate of LNs, the number of metastatic LNs dissection, various intraoperative outcomes, and postoperative complications. RESULTS: A total of 9 studies including 1770 participants (502 in the CNs group and 1268 in the control group) were included. As compared to the blank control group, the CNs group detected 10.46 more LNs in each patient (WMD = 10.46, 95% CI: 6.63 ~ 14.28, p < 0.00001, I2 = 91%), and also significantly more metastatic LNs (WMD = 2.63, 95% CI: 1.43 ~ 3.83, p < 0.0001, I2 = 41%). However, there was no significant difference in the rate of metastatic LNs between the CNs and control groups (OR = 1.37, 95% CI: 0.94 ~ 2.00, P = 0.1, I2 = 89%). In addition, there was no increase in operative time, intraoperative blood loss, and postoperative complications associated with CNs-guided gastrectomy. CONCLUSION: CNs-guided gastrectomy is safe and effective, and can increase the efficiency of LN dissection without increasing the risk of surgery.

Correction to "MicroRNA-320a suppresses tumor progression by targeting PBX3 in gastric cancer and is downregulated by DNA methylation".

[This corrects the article on p. 842 in vol. 11, PMID: 31662823.].

[Effects of Nano-membrane on Aerobic Composting Process and Odor Emission of Livestock Manure].

Aerobic composting is an important approach to treat livestock manure; however, traditional composting has some problems, such as low efficiency, or odorous pollution. In order to speed up the composting process and reduce malodorous gas emissions, this study explored the mechanism of nano-membrane for improving the efficiency of livestock manure composting. A trough aerobic composting experiment was set up to evaluate the physicochemical properties, enzyme activities, and emission of odorous gases. The results showed that covering with nano-membrane could accelerate the temperature rise; reduce the pH, organic matter(OM), and ammonia nitrogen(NH4+-N); increase electrical conductivity(EC); enhance the activities of urease, protease, cellulase, xylanase, and peroxidase; while the total cumulative emissions of NH3, H2S, and TVOC were reduced by 58%, 100%, and 61%, respectively. The correlation analysis showed that most enzyme activities were easily affected by temperature(T), EC, OM, and C/N. The emission rate of NH3 was positively correlated with T and negatively correlated with pH, and TVOC was significantly correlated with various physicochemical properties. This experiment showed that covering nano-membrane could accelerate the compost maturity and reduce the emission of odorous gases. This approach has no health risks and produces low malodorous gas, which may effectively solve the problem of pollutant emission caused by livestock manure compost fermentation, promoting the green and sustainable development of the breeding industry. In addition, it facilitates livestock manure fertilizer application, and provides technical support for the development of resource utilization of biomass waste.

Common Strategy: Mounting the Rod-like Ni-Based MOF on Hydrangea-Shaped Nickel Hydroxide for Superior Electrocatalytic Methanol Oxidation Reaction.

Developing efficient metal-organic framework (MOF)-based electrocatalysts with improvable activity and persistence toward the methanol oxidation reaction (MOR) is attracting great research attention but still remains an enormous challenge. Herein, a facile strategy, hydrangea-shaped nickel hydroxide template-directed synthesis of the hierarchically structured Ni-MOF on the Ni(OH)2 heterocomposite (denoted as Ni-Ni) for efficient MOR, is developed. The unique hierarchical structure and synergistic effect of the heterocomposite afford more exposed active sites, a facile ion diffusion path, and improved conductivity, favorable for improving MOR catalytic performance. Remarkably, the optimized Ni-Ni-2 material delivers an excellent activity with a high peak current density (24.6 mA cm-2). Furthermore, to prove the universality of this strategy, NixCu1-x(OH)2 isometallic hydroxide was used as the precursor, and a series of MOF-74/CuxNi1-x(OH)2 (denoted as Ni-NiCu) heterogeneous materials have been prepared and could be used as an effective electrocatalyst to catalyze MOR. The results indicate that this strategy can be used in the synthesis of other new composite materials with specific hierarchical structures for a more efficient electrocatalytic system.

Investigation on the Component Evolution of a Tetranuclear Nickel-Cluster-Based Metal-Organic Framework in an Electrochemical Oxidation Reaction.

Understanding the active species derived from metal-organic frameworks (MOFs) plays a vital role in the fabrication of highly efficient and stable oxygen evolution reaction (OER) electrocatalysts. Herein, a new alkaline-stable 3D nickel metal-organic framework (Ni-MOF), containing a 1D rod-packing chain structure fused with a tetranuclear nickel cluster [Ni4(µ3-OH)2], is used as a target material to explore its OER properties. The electrocatalytic activities of pure Ni-MOF and hybrid materials made from Ni-MOF with different acetylene black loaded electrodes, such as glassy carbon, fluorine-doped tin oxide, and nickel foam, have been evaluated. Further analysis unravels that the enhanced OER performance might be attributed to the synergistic interactions of two catalytic active species between in situ formed ß-Ni(OH)2 and a tetranuclear Ni4(µ3-OH)2 cluster in Ni-MOF. The findings will shed fresh light on the fabrication of MOF-derived catalysts for efficient electrochemical energy conversion.

MicroRNA-320a suppresses tumor progression by targeting PBX3 in gastric cancer and is downregulated by DNA methylation.

BACKGROUND: Ectopic expression of miRNAs promotes tumor development and progression. miRNA (miR)-320a is downregulated in many cancers, including gastric cancer (GC). However, the mechanism underlying its downregulation and the role of miR-320a in GC are unknown. AIM: To determine expression and biological functions of miR-320a in GC and investigate the underlying molecular mechanisms. METHODS: Quantitative real-time polymerase chain reaction (PCR) was used to determine expression of miR-320a in GC cell lines and tissues. TargetScanHuman7.1, miRDB, and microRNA.org were used to predict the possible targets of miR-320a, and a dual luciferase assay was used to confirm the findings. Western blotting was used to detect the protein levels of pre-B-cell leukemia homeobox 3 (PBX3) in GC cells and tissue samples. Cell Counting Kit-8 proliferation, Transwell, wound healing, and apoptosis assays were performed to analyze the biological functions of miR-320a in GC cells. Methylation-specific PCR was used to analyze the methylation level of the miR-320a promoter CpG islands. 5-Aza-2'-deoxycytidine (5-Aza-CdR) and trichostatin A (TSA) were used to treat GC cells. RESULTS: miR-320a expression was lower in GC cell lines and tissues than in the normal gastric mucosa cell line GES-1 and matched adjacent normal tissues. miR-320a overexpression suppressed GC cell proliferation, invasion and migration, and induced apoptosis. PBX3 was a target of miR-320a in GC. The methylation level of the miR-320a promoter CpG islands was elevated and this was partly reversed by 5-Aza-CdR and TSA. CONCLUSION: miR-320a acts as a tumor suppressor and inhibits malignant behavior of GC cells, partly by targeting PBX3. DNA methylation is an important mechanism associated with low expression of miR-320a.

Integration of Semiconductor Oxide and a Microporous (3,10)-Connected Co6-Based Metal-Organic Framework for Enhanced Oxygen Evolution Reaction.

Developing high-efficiency and cost-effective electrocatalytic oxygen evolution reaction (OER) catalysts would determine the future distributions of energy conversion technologies. Metal-organic frameworks (MOFs), with unsaturated active metal sites, functionalized organic linkers, and large surface areas, are emerging heterogeneous electrocatalysts for the water oxidation process. Herein, we report an oxygen-evolving microporous (3,10)-connected Co6-based MOF (denoted as CTGU-14) for the electrocatalytic OER. Moreover, the integration of Co-MOF and SnO2, SnO2 (15%) & CTGU-14 composite attains remarkable electrochemical OER performance with a small Tafel slope of 68 mV·dec-1, a positive overpotential of 388 mV at 10 mA·cm-2, and overall durability in an alkali medium. The superior OER activities might be ascribed to more convenient electron transfer from the SnO2 additive to the electrode medium, effective surface area and unsaturated active cobalt centers, and more beneficial delivery for hydroxy radicals in the microporous Co-MOF skeleton in the process of the OER.

Extent of breast cancer type 1 promoter methylation correlates with clinicopathological features in breast cancers.

AIM OF STUDY: The current meta-analysis investigated the correlation between breast cancer type 1 (BRCA1) promoter methylation and the clinicopathological features of breast cancer (BC). MATERIALS AND METHODS: An electronic literature search was performed to identify and select cohort studies, by employing stringent inclusion and exclusion criteria, for data relevant to promoter methylation of BRCA1 and BC. Statistical analysis of the extracted data was performed using comprehensive meta-analysis 2.0 software (CMA 2.0) (Biostat Inc., Englewood, New Jersey, USA). RESULTS: A total of 125 published studies were retrieved from the literature search, and finally, 18 cohort studies meeting our inclusion criteria were incorporated into our meta-analysis. The 18 studies contained a total of 3213 BC patients. Meta-analysis results revealed that BRCA1 promoter methylation in BC patients with high and moderately differentiated tumors (I-II) was significantly lower than patients with poorly-differentiation tumors (III) (odds ratio [OR] =0.450, 95% confidence interval [95% CI] =0.241-0.838, P = 0.012). BRCA1 promoter methylation in BC patients with lymph node (LN) metastasis was significantly higher than patients without LN metastasis (OR = 2.244, 95% CI = 1.278-3.940, P = 0.005). The results of ethnicity-based subgroup analysis showed a significant difference in histological grade of BC on Asians, LN metastasis of BC in Asians and Caucasians, subtypes of BC in Caucasians, and age at diagnosis of BC patients in Caucasians (all P < 0.05). CONCLUSIONS: Our meta-analysis revealed that BRCA1 promoter methylation status is linked to tumor grade and LN metastasis of BC.

Up-regulation of CRKL by microRNA-335 methylation is associated with poor prognosis in gastric cancer.

BACKGROUND: MicroRNAs have been suggested to play a vital role in regulating carcinogenesis, tumor progression and invasion. MiR-335 is involved in suppressing metastasis and invasion in various human cancers. However, the mechanisms responsible for the aberrant expression of miR-335 in gastric cancer (GC) remain unknown. METHODS: Expression of miR-335 in four GC cell lines and 231 GC tissues was determined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). DNA methylation status in the CpG islands upstream of miR-335 in GC cell lines and tissues was determined by methylation-specific PCR and bisulfite sequence-PCR. The effects of the demethylating agent 5-aza-2'-deoxycytidine on cell proliferation, apoptosis, cell cycle, migration, and invasion were investigated in GC cell lines. RESULTS: Cancer-specific methylation was detected in the upstream CpG-rich regions of miR-335, which dramatically silenced its transcriptional activity in GC cell lines and tissues. Low levels of miR-335 expression and high levels of miR-335 methylation in GC tissues were associated with poor clinical features and prognosis. Restoration of miR-335 expression in GC cells promoted cell apoptosis, inhibited tumor cell migration, invasion, and proliferation, and arrested the cell cycle at G0/G1 phase. Overexpression of miR-335 significantly reduced the activity of a luciferase reporter containing the 3' untranslated region of V-crk avian sarcoma virus CT10 oncogene homolog-like (CRKL). CONCLUSIONS: MiR-335 functions as a tumor suppressor and may be silenced by promoter hypermethylation. It plays a role in inhibiting tumor cell migration, invasion, and proliferation, arresting the cell cycle at G0/G1 phase, and promoting apoptosis in GC cells through targeting CRKL.

Role of RASSF1A promoter methylation in the pathogenesis of hepatocellular carcinoma: a meta-analysis of 21 cohort studies.

We carried out the current meta-analysis aiming to comprehensively assess the potential role of RASSF1A aberrant promoter methylation in the pathogenesis of hepatocellular carcinoma (HCC). A range of electronic databases were searched: Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013) and the Chinese Biomedical Database (CBM) (1982-2013) without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude risk difference (RD) with their 95% confidence interval (95% CI) was calculated. In the present meta-analysis, 21 clinical cohort studies with a total of 1,205 HCC patients were included. The results of our meta-analysis illustrated that the frequency of RASSF1A promoter methylation in cancer tissues were significantly higher than those of normal, adjacent and benign tissues (cancer tissues vs. normal tissues: RD = 0.63, 95% CI 0.53-0.73, P < 0.001; cancer tissues vs. adjacent tissues: RD = 0.43, 95% CI 0.33-0.53, P < 0.001; cancer tissues vs. benign tissues: RD = 0.48, 95% CI 038-0.58, P < 0.001; respectively). Further subgroup by ethnicity demonstrated that RASSF1A aberrant promoter methylation was correlated with the pathogenesis of HCC among both Asians and Caucasians (all P < 0.05). The current meta-analysis suggests that RASSF1A aberrant promoter methylation may be implicated in the pathogenesis of HCC. Thus, detection of RASSF1A promoter methylation may be a helpful and valuable biomarker for diagnosis and prognosis of HCC.